An attentive multi-camera system
NASA Astrophysics Data System (ADS)
Napoletano, Paolo; Tisato, Francesco
2014-03-01
Intelligent multi-camera systems that integrate computer vision algorithms are not error free, and thus both false positive and negative detections need to be revised by a specialized human operator. Traditional multi-camera systems usually include a control center with a wall of monitors displaying videos from each camera of the network. Nevertheless, as the number of cameras increases, switching from a camera to another becomes hard for a human operator. In this work we propose a new method that dynamically selects and displays the content of a video camera from all the available contents in the multi-camera system. The proposed method is based on a computational model of human visual attention that integrates top-down and bottom-up cues. We believe that this is the first work that tries to use a model of human visual attention for the dynamic selection of the camera view of a multi-camera system. The proposed method has been experimented in a given scenario and has demonstrated its effectiveness with respect to the other methods and manually generated ground-truth. The effectiveness has been evaluated in terms of number of correct best-views generated by the method with respect to the camera views manually generated by a human operator.
Automatic multi-camera calibration for deployable positioning systems
NASA Astrophysics Data System (ADS)
Axelsson, Maria; Karlsson, Mikael; Rudner, Staffan
2012-06-01
Surveillance with automated positioning and tracking of subjects and vehicles in 3D is desired in many defence and security applications. Camera systems with stereo or multiple cameras are often used for 3D positioning. In such systems, accurate camera calibration is needed to obtain a reliable 3D position estimate. There is also a need for automated camera calibration to facilitate fast deployment of semi-mobile multi-camera 3D positioning systems. In this paper we investigate a method for automatic calibration of the extrinsic camera parameters (relative camera pose and orientation) of a multi-camera positioning system. It is based on estimation of the essential matrix between each camera pair using the 5-point method for intrinsically calibrated cameras. The method is compared to a manual calibration method using real HD video data from a field trial with a multicamera positioning system. The method is also evaluated on simulated data from a stereo camera model. The results show that the reprojection error of the automated camera calibration method is close to or smaller than the error for the manual calibration method and that the automated calibration method can replace the manual calibration.
Multi-color pyrometry imaging system and method of operating the same
Estevadeordal, Jordi; Nirmalan, Nirm Velumylum; Tralshawala, Nilesh; Bailey, Jeremy Clyde
2017-03-21
A multi-color pyrometry imaging system for a high-temperature asset includes at least one viewing port in optical communication with at least one high-temperature component of the high-temperature asset. The system also includes at least one camera device in optical communication with the at least one viewing port. The at least one camera device includes a camera enclosure and at least one camera aperture defined in the camera enclosure, The at least one camera aperture is in optical communication with the at least one viewing port. The at least one camera device also includes a multi-color filtering mechanism coupled to the enclosure. The multi-color filtering mechanism is configured to sequentially transmit photons within a first predetermined wavelength band and transmit photons within a second predetermined wavelength band that is different than the first predetermined wavelength band.
A detailed comparison of single-camera light-field PIV and tomographic PIV
NASA Astrophysics Data System (ADS)
Shi, Shengxian; Ding, Junfei; Atkinson, Callum; Soria, Julio; New, T. H.
2018-03-01
This paper conducts a comprehensive study between the single-camera light-field particle image velocimetry (LF-PIV) and the multi-camera tomographic particle image velocimetry (Tomo-PIV). Simulation studies were first performed using synthetic light-field and tomographic particle images, which extensively examine the difference between these two techniques by varying key parameters such as pixel to microlens ratio (PMR), light-field camera Tomo-camera pixel ratio (LTPR), particle seeding density and tomographic camera number. Simulation results indicate that the single LF-PIV can achieve accuracy consistent with that of multi-camera Tomo-PIV, but requires the use of overall greater number of pixels. Experimental studies were then conducted by simultaneously measuring low-speed jet flow with single-camera LF-PIV and four-camera Tomo-PIV systems. Experiments confirm that given a sufficiently high pixel resolution, a single-camera LF-PIV system can indeed deliver volumetric velocity field measurements for an equivalent field of view with a spatial resolution commensurate with those of multi-camera Tomo-PIV system, enabling accurate 3D measurements in applications where optical access is limited.
Photometric Calibration and Image Stitching for a Large Field of View Multi-Camera System
Lu, Yu; Wang, Keyi; Fan, Gongshu
2016-01-01
A new compact large field of view (FOV) multi-camera system is introduced. The camera is based on seven tiny complementary metal-oxide-semiconductor sensor modules covering over 160° × 160° FOV. Although image stitching has been studied extensively, sensor and lens differences have not been considered in previous multi-camera devices. In this study, we have calibrated the photometric characteristics of the multi-camera device. Lenses were not mounted on the sensor in the process of radiometric response calibration to eliminate the influence of the focusing effect of uniform light from an integrating sphere. Linearity range of the radiometric response, non-linearity response characteristics, sensitivity, and dark current of the camera response function are presented. The R, G, and B channels have different responses for the same illuminance. Vignetting artifact patterns have been tested. The actual luminance of the object is retrieved by sensor calibration results, and is used to blend images to make panoramas reflect the objective luminance more objectively. This compensates for the limitation of stitching images that are more realistic only through the smoothing method. The dynamic range limitation of can be resolved by using multiple cameras that cover a large field of view instead of a single image sensor with a wide-angle lens. The dynamic range is expanded by 48-fold in this system. We can obtain seven images in one shot with this multi-camera system, at 13 frames per second. PMID:27077857
User-assisted visual search and tracking across distributed multi-camera networks
NASA Astrophysics Data System (ADS)
Raja, Yogesh; Gong, Shaogang; Xiang, Tao
2011-11-01
Human CCTV operators face several challenges in their task which can lead to missed events, people or associations, including: (a) data overload in large distributed multi-camera environments; (b) short attention span; (c) limited knowledge of what to look for; and (d) lack of access to non-visual contextual intelligence to aid search. Developing a system to aid human operators and alleviate such burdens requires addressing the problem of automatic re-identification of people across disjoint camera views, a matching task made difficult by factors such as lighting, viewpoint and pose changes and for which absolute scoring approaches are not best suited. Accordingly, we describe a distributed multi-camera tracking (MCT) system to visually aid human operators in associating people and objects effectively over multiple disjoint camera views in a large public space. The system comprises three key novel components: (1) relative measures of ranking rather than absolute scoring to learn the best features for matching; (2) multi-camera behaviour profiling as higher-level knowledge to reduce the search space and increase the chance of finding correct matches; and (3) human-assisted data mining to interactively guide search and in the process recover missing detections and discover previously unknown associations. We provide an extensive evaluation of the greater effectiveness of the system as compared to existing approaches on industry-standard i-LIDS multi-camera data.
Fisheye Multi-Camera System Calibration for Surveying Narrow and Complex Architectures
NASA Astrophysics Data System (ADS)
Perfetti, L.; Polari, C.; Fassi, F.
2018-05-01
Narrow spaces and passages are not a rare encounter in cultural heritage, the shape and extension of those areas place a serious challenge on any techniques one may choose to survey their 3D geometry. Especially on techniques that make use of stationary instrumentation like terrestrial laser scanning. The ratio between space extension and cross section width of many corridors and staircases can easily lead to distortions/drift of the 3D reconstruction because of the problem of propagation of uncertainty. This paper investigates the use of fisheye photogrammetry to produce the 3D reconstruction of such spaces and presents some tests to contain the degree of freedom of the photogrammetric network, thereby containing the drift of long data set as well. The idea is that of employing a multi-camera system composed of several fisheye cameras and to implement distances and relative orientation constraints, as well as the pre-calibration of the internal parameters for each camera, within the bundle adjustment. For the beginning of this investigation, we used the NCTech iSTAR panoramic camera as a rigid multi-camera system. The case study of the Amedeo Spire of the Milan Cathedral, that encloses a spiral staircase, is the stage for all the tests. Comparisons have been made between the results obtained with the multi-camera configuration, the auto-stitched equirectangular images and a data set obtained with a monocular fisheye configuration using a full frame DSLR. Results show improved accuracy, down to millimetres, using a rigidly constrained multi-camera.
Video auto stitching in multicamera surveillance system
NASA Astrophysics Data System (ADS)
He, Bin; Zhao, Gang; Liu, Qifang; Li, Yangyang
2012-01-01
This paper concerns the problem of video stitching automatically in a multi-camera surveillance system. Previous approaches have used multiple calibrated cameras for video mosaic in large scale monitoring application. In this work, we formulate video stitching as a multi-image registration and blending problem, and not all cameras are needed to be calibrated except a few selected master cameras. SURF is used to find matched pairs of image key points from different cameras, and then camera pose is estimated and refined. Homography matrix is employed to calculate overlapping pixels and finally implement boundary resample algorithm to blend images. The result of simulation demonstrates the efficiency of our method.
Video auto stitching in multicamera surveillance system
NASA Astrophysics Data System (ADS)
He, Bin; Zhao, Gang; Liu, Qifang; Li, Yangyang
2011-12-01
This paper concerns the problem of video stitching automatically in a multi-camera surveillance system. Previous approaches have used multiple calibrated cameras for video mosaic in large scale monitoring application. In this work, we formulate video stitching as a multi-image registration and blending problem, and not all cameras are needed to be calibrated except a few selected master cameras. SURF is used to find matched pairs of image key points from different cameras, and then camera pose is estimated and refined. Homography matrix is employed to calculate overlapping pixels and finally implement boundary resample algorithm to blend images. The result of simulation demonstrates the efficiency of our method.
NASA Astrophysics Data System (ADS)
Xia, Renbo; Hu, Maobang; Zhao, Jibin; Chen, Songlin; Chen, Yueling
2018-06-01
Multi-camera vision systems are often needed to achieve large-scale and high-precision measurement because these systems have larger fields of view (FOV) than a single camera. Multiple cameras may have no or narrow overlapping FOVs in many applications, which pose a huge challenge to global calibration. This paper presents a global calibration method for multi-cameras without overlapping FOVs based on photogrammetry technology and a reconfigurable target. Firstly, two planar targets are fixed together and made into a long target according to the distance between the two cameras to be calibrated. The relative positions of the two planar targets can be obtained by photogrammetric methods and used as invariant constraints in global calibration. Then, the reprojection errors of target feature points in the two cameras’ coordinate systems are calculated at the same time and optimized by the Levenberg–Marquardt algorithm to find the optimal solution of the transformation matrix between the two cameras. Finally, all the camera coordinate systems are converted to the reference coordinate system in order to achieve global calibration. Experiments show that the proposed method has the advantages of high accuracy (the RMS error is 0.04 mm) and low cost and is especially suitable for on-site calibration.
An intelligent space for mobile robot localization using a multi-camera system.
Rampinelli, Mariana; Covre, Vitor Buback; de Queiroz, Felippe Mendonça; Vassallo, Raquel Frizera; Bastos-Filho, Teodiano Freire; Mazo, Manuel
2014-08-15
This paper describes an intelligent space, whose objective is to localize and control robots or robotic wheelchairs to help people. Such an intelligent space has 11 cameras distributed in two laboratories and a corridor. The cameras are fixed in the environment, and image capturing is done synchronously. The system was programmed as a client/server with TCP/IP connections, and a communication protocol was defined. The client coordinates the activities inside the intelligent space, and the servers provide the information needed for that. Once the cameras are used for localization, they have to be properly calibrated. Therefore, a calibration method for a multi-camera network is also proposed in this paper. A robot is used to move a calibration pattern throughout the field of view of the cameras. Then, the captured images and the robot odometry are used for calibration. As a result, the proposed algorithm provides a solution for multi-camera calibration and robot localization at the same time. The intelligent space and the calibration method were evaluated under different scenarios using computer simulations and real experiments. The results demonstrate the proper functioning of the intelligent space and validate the multi-camera calibration method, which also improves robot localization.
An Intelligent Space for Mobile Robot Localization Using a Multi-Camera System
Rampinelli, Mariana.; Covre, Vitor Buback.; de Queiroz, Felippe Mendonça.; Vassallo, Raquel Frizera.; Bastos-Filho, Teodiano Freire.; Mazo, Manuel.
2014-01-01
This paper describes an intelligent space, whose objective is to localize and control robots or robotic wheelchairs to help people. Such an intelligent space has 11 cameras distributed in two laboratories and a corridor. The cameras are fixed in the environment, and image capturing is done synchronously. The system was programmed as a client/server with TCP/IP connections, and a communication protocol was defined. The client coordinates the activities inside the intelligent space, and the servers provide the information needed for that. Once the cameras are used for localization, they have to be properly calibrated. Therefore, a calibration method for a multi-camera network is also proposed in this paper. A robot is used to move a calibration pattern throughout the field of view of the cameras. Then, the captured images and the robot odometry are used for calibration. As a result, the proposed algorithm provides a solution for multi-camera calibration and robot localization at the same time. The intelligent space and the calibration method were evaluated under different scenarios using computer simulations and real experiments. The results demonstrate the proper functioning of the intelligent space and validate the multi-camera calibration method, which also improves robot localization. PMID:25196009
A practical approach for active camera coordination based on a fusion-driven multi-agent system
NASA Astrophysics Data System (ADS)
Bustamante, Alvaro Luis; Molina, José M.; Patricio, Miguel A.
2014-04-01
In this paper, we propose a multi-agent system architecture to manage spatially distributed active (or pan-tilt-zoom) cameras. Traditional video surveillance algorithms are of no use for active cameras, and we have to look at different approaches. Such multi-sensor surveillance systems have to be designed to solve two related problems: data fusion and coordinated sensor-task management. Generally, architectures proposed for the coordinated operation of multiple cameras are based on the centralisation of management decisions at the fusion centre. However, the existence of intelligent sensors capable of decision making brings with it the possibility of conceiving alternative decentralised architectures. This problem is approached by means of a MAS, integrating data fusion as an integral part of the architecture for distributed coordination purposes. This paper presents the MAS architecture and system agents.
NASA Astrophysics Data System (ADS)
Liu, Yu-Che; Huang, Chung-Lin
2013-03-01
This paper proposes a multi-PTZ-camera control mechanism to acquire close-up imagery of human objects in a surveillance system. The control algorithm is based on the output of multi-camera, multi-target tracking. Three main concerns of the algorithm are (1) the imagery of human object's face for biometric purposes, (2) the optimal video quality of the human objects, and (3) minimum hand-off time. Here, we define an objective function based on the expected capture conditions such as the camera-subject distance, pan tile angles of capture, face visibility and others. Such objective function serves to effectively balance the number of captures per subject and quality of captures. In the experiments, we demonstrate the performance of the system which operates in real-time under real world conditions on three PTZ cameras.
The California All-sky Meteor Surveillance (CAMS) System
NASA Astrophysics Data System (ADS)
Gural, P. S.
2011-01-01
A unique next generation multi-camera, multi-site video meteor system is being developed and deployed in California to provide high accuracy orbits of simultaneously captured meteors. Included herein is a description of the goals, concept of operations, hardware, and software development progress. An appendix contains a meteor camera performance trade study made for video systems circa 2010.
Stability analysis for a multi-camera photogrammetric system.
Habib, Ayman; Detchev, Ivan; Kwak, Eunju
2014-08-18
Consumer-grade digital cameras suffer from geometrical instability that may cause problems when used in photogrammetric applications. This paper provides a comprehensive review of this issue of interior orientation parameter variation over time, it explains the common ways used for coping with the issue, and describes the existing methods for performing stability analysis for a single camera. The paper then points out the lack of coverage of stability analysis for multi-camera systems, suggests a modification of the collinearity model to be used for the calibration of an entire photogrammetric system, and proposes three methods for system stability analysis. The proposed methods explore the impact of the changes in interior orientation and relative orientation/mounting parameters on the reconstruction process. Rather than relying on ground truth in real datasets to check the system calibration stability, the proposed methods are simulation-based. Experiment results are shown, where a multi-camera photogrammetric system was calibrated three times, and stability analysis was performed on the system calibration parameters from the three sessions. The proposed simulation-based methods provided results that were compatible with a real-data based approach for evaluating the impact of changes in the system calibration parameters on the three-dimensional reconstruction.
Stability Analysis for a Multi-Camera Photogrammetric System
Habib, Ayman; Detchev, Ivan; Kwak, Eunju
2014-01-01
Consumer-grade digital cameras suffer from geometrical instability that may cause problems when used in photogrammetric applications. This paper provides a comprehensive review of this issue of interior orientation parameter variation over time, it explains the common ways used for coping with the issue, and describes the existing methods for performing stability analysis for a single camera. The paper then points out the lack of coverage of stability analysis for multi-camera systems, suggests a modification of the collinearity model to be used for the calibration of an entire photogrammetric system, and proposes three methods for system stability analysis. The proposed methods explore the impact of the changes in interior orientation and relative orientation/mounting parameters on the reconstruction process. Rather than relying on ground truth in real datasets to check the system calibration stability, the proposed methods are simulation-based. Experiment results are shown, where a multi-camera photogrammetric system was calibrated three times, and stability analysis was performed on the system calibration parameters from the three sessions. The proposed simulation-based methods provided results that were compatible with a real-data based approach for evaluating the impact of changes in the system calibration parameters on the three-dimensional reconstruction. PMID:25196012
Adjustment of multi-CCD-chip-color-camera heads
NASA Astrophysics Data System (ADS)
Guyenot, Volker; Tittelbach, Guenther; Palme, Martin
1999-09-01
The principle of beam-splitter-multi-chip cameras consists in splitting an image into differential multiple images of different spectral ranges and in distributing these onto separate black and white CCD-sensors. The resulting electrical signals from the chips are recombined to produce a high quality color picture on the monitor. Because this principle guarantees higher resolution and sensitivity in comparison to conventional single-chip camera heads, the greater effort is acceptable. Furthermore, multi-chip cameras obtain the compete spectral information for each individual object point while single-chip system must rely on interpolation. In a joint project, Fraunhofer IOF and STRACON GmbH and in future COBRA electronic GmbH develop methods for designing the optics and dichroitic mirror system of such prism color beam splitter devices. Additionally, techniques and equipment for the alignment and assembly of color beam splitter-multi-CCD-devices on the basis of gluing with UV-curable adhesives have been developed, too.
A single camera photogrammetry system for multi-angle fast localization of EEG electrodes.
Qian, Shuo; Sheng, Yang
2011-11-01
Photogrammetry has become an effective method for the determination of electroencephalography (EEG) electrode positions in three dimensions (3D). Capturing multi-angle images of the electrodes on the head is a fundamental objective in the design of photogrammetry system for EEG localization. Methods in previous studies are all based on the use of either a rotating camera or multiple cameras, which are time-consuming or not cost-effective. This study aims to present a novel photogrammetry system that can realize simultaneous acquisition of multi-angle head images in a single camera position. Aligning two planar mirrors with the angle of 51.4°, seven views of the head with 25 electrodes are captured simultaneously by the digital camera placed in front of them. A complete set of algorithms for electrode recognition, matching, and 3D reconstruction is developed. It is found that the elapsed time of the whole localization procedure is about 3 min, and camera calibration computation takes about 1 min, after the measurement of calibration points. The positioning accuracy with the maximum error of 1.19 mm is acceptable. Experimental results demonstrate that the proposed system provides a fast and cost-effective method for the EEG positioning.
Scalable software architecture for on-line multi-camera video processing
NASA Astrophysics Data System (ADS)
Camplani, Massimo; Salgado, Luis
2011-03-01
In this paper we present a scalable software architecture for on-line multi-camera video processing, that guarantees a good trade off between computational power, scalability and flexibility. The software system is modular and its main blocks are the Processing Units (PUs), and the Central Unit. The Central Unit works as a supervisor of the running PUs and each PU manages the acquisition phase and the processing phase. Furthermore, an approach to easily parallelize the desired processing application has been presented. In this paper, as case study, we apply the proposed software architecture to a multi-camera system in order to efficiently manage multiple 2D object detection modules in a real-time scenario. System performance has been evaluated under different load conditions such as number of cameras and image sizes. The results show that the software architecture scales well with the number of camera and can easily works with different image formats respecting the real time constraints. Moreover, the parallelization approach can be used in order to speed up the processing tasks with a low level of overhead.
Nuclear medicine imaging system
Bennett, Gerald W.; Brill, A. Bertrand; Bizais, Yves J.; Rowe, R. Wanda; Zubal, I. George
1986-01-07
A nuclear medicine imaging system having two large field of view scintillation cameras mounted on a rotatable gantry and being movable diametrically toward or away from each other is disclosed. In addition, each camera may be rotated about an axis perpendicular to the diameter of the gantry. The movement of the cameras allows the system to be used for a variety of studies, including positron annihilation, and conventional single photon emission, as well as static orthogonal dual multi-pinhole tomography. In orthogonal dual multi-pinhole tomography, each camera is fitted with a seven pinhole collimator to provide seven views from slightly different perspectives. By using two cameras at an angle to each other, improved sensitivity and depth resolution is achieved. The computer system and interface acquires and stores a broad range of information in list mode, including patient physiological data, energy data over the full range detected by the cameras, and the camera position. The list mode acquisition permits the study of attenuation as a result of Compton scatter, as well as studies involving the isolation and correlation of energy with a range of physiological conditions.
Nuclear medicine imaging system
Bennett, Gerald W.; Brill, A. Bertrand; Bizais, Yves J. C.; Rowe, R. Wanda; Zubal, I. George
1986-01-01
A nuclear medicine imaging system having two large field of view scintillation cameras mounted on a rotatable gantry and being movable diametrically toward or away from each other is disclosed. In addition, each camera may be rotated about an axis perpendicular to the diameter of the gantry. The movement of the cameras allows the system to be used for a variety of studies, including positron annihilation, and conventional single photon emission, as well as static orthogonal dual multi-pinhole tomography. In orthogonal dual multi-pinhole tomography, each camera is fitted with a seven pinhole collimator to provide seven views from slightly different perspectives. By using two cameras at an angle to each other, improved sensitivity and depth resolution is achieved. The computer system and interface acquires and stores a broad range of information in list mode, including patient physiological data, energy data over the full range detected by the cameras, and the camera position. The list mode acquisition permits the study of attenuation as a result of Compton scatter, as well as studies involving the isolation and correlation of energy with a range of physiological conditions.
Distributed Sensing and Processing for Multi-Camera Networks
NASA Astrophysics Data System (ADS)
Sankaranarayanan, Aswin C.; Chellappa, Rama; Baraniuk, Richard G.
Sensor networks with large numbers of cameras are becoming increasingly prevalent in a wide range of applications, including video conferencing, motion capture, surveillance, and clinical diagnostics. In this chapter, we identify some of the fundamental challenges in designing such systems: robust statistical inference, computationally efficiency, and opportunistic and parsimonious sensing. We show that the geometric constraints induced by the imaging process are extremely useful for identifying and designing optimal estimators for object detection and tracking tasks. We also derive pipelined and parallelized implementations of popular tools used for statistical inference in non-linear systems, of which multi-camera systems are examples. Finally, we highlight the use of the emerging theory of compressive sensing in reducing the amount of data sensed and communicated by a camera network.
A Semi-Automatic Image-Based Close Range 3D Modeling Pipeline Using a Multi-Camera Configuration
Rau, Jiann-Yeou; Yeh, Po-Chia
2012-01-01
The generation of photo-realistic 3D models is an important task for digital recording of cultural heritage objects. This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object. Multiple digital single lens reflex (DSLR) cameras are adopted and fixed with invariant relative orientations. Instead of photo-triangulation after image acquisition, calibration is performed to estimate the exterior orientation parameters of the multi-camera configuration which can be processed fully automatically using coded targets. The calibrated orientation parameters of all cameras are applied to images taken using the same camera configuration. This means that when performing multi-image matching for surface point cloud generation, the orientation parameters will remain the same as the calibrated results, even when the target has changed. Base on this invariant character, the whole 3D modeling pipeline can be performed completely automatically, once the whole system has been calibrated and the software was seamlessly integrated. Several experiments were conducted to prove the feasibility of the proposed system. Images observed include that of a human being, eight Buddhist statues, and a stone sculpture. The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner. The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333. It demonstrates the feasibility of the proposed low-cost image-based 3D modeling pipeline and its applicability to a large quantity of antiques stored in a museum. PMID:23112656
A semi-automatic image-based close range 3D modeling pipeline using a multi-camera configuration.
Rau, Jiann-Yeou; Yeh, Po-Chia
2012-01-01
The generation of photo-realistic 3D models is an important task for digital recording of cultural heritage objects. This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object. Multiple digital single lens reflex (DSLR) cameras are adopted and fixed with invariant relative orientations. Instead of photo-triangulation after image acquisition, calibration is performed to estimate the exterior orientation parameters of the multi-camera configuration which can be processed fully automatically using coded targets. The calibrated orientation parameters of all cameras are applied to images taken using the same camera configuration. This means that when performing multi-image matching for surface point cloud generation, the orientation parameters will remain the same as the calibrated results, even when the target has changed. Base on this invariant character, the whole 3D modeling pipeline can be performed completely automatically, once the whole system has been calibrated and the software was seamlessly integrated. Several experiments were conducted to prove the feasibility of the proposed system. Images observed include that of a human being, eight Buddhist statues, and a stone sculpture. The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner. The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333. It demonstrates the feasibility of the proposed low-cost image-based 3D modeling pipeline and its applicability to a large quantity of antiques stored in a museum.
Multi-Target Camera Tracking, Hand-off and Display LDRD 158819 Final Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Robert J.
2014-10-01
Modern security control rooms gather video and sensor feeds from tens to hundreds of cameras. Advanced camera analytics can detect motion from individual video streams and convert unexpected motion into alarms, but the interpretation of these alarms depends heavily upon human operators. Unfortunately, these operators can be overwhelmed when a large number of events happen simultaneously, or lulled into complacency due to frequent false alarms. This LDRD project has focused on improving video surveillance-based security systems by changing the fundamental focus from the cameras to the targets being tracked. If properly integrated, more cameras shouldn’t lead to more alarms, moremore » monitors, more operators, and increased response latency but instead should lead to better information and more rapid response times. For the course of the LDRD we have been developing algorithms that take live video imagery from multiple video cameras, identify individual moving targets from the background imagery, and then display the results in a single 3D interactive video. In this document we summarize the work in developing this multi-camera, multi-target system, including lessons learned, tools developed, technologies explored, and a description of current capability.« less
Multi-target camera tracking, hand-off and display LDRD 158819 final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, Robert J.
2014-10-01
Modern security control rooms gather video and sensor feeds from tens to hundreds of cameras. Advanced camera analytics can detect motion from individual video streams and convert unexpected motion into alarms, but the interpretation of these alarms depends heavily upon human operators. Unfortunately, these operators can be overwhelmed when a large number of events happen simultaneously, or lulled into complacency due to frequent false alarms. This LDRD project has focused on improving video surveillance-based security systems by changing the fundamental focus from the cameras to the targets being tracked. If properly integrated, more cameras shouldn't lead to more alarms, moremore » monitors, more operators, and increased response latency but instead should lead to better information and more rapid response times. For the course of the LDRD we have been developing algorithms that take live video imagery from multiple video cameras, identifies individual moving targets from the background imagery, and then displays the results in a single 3D interactive video. In this document we summarize the work in developing this multi-camera, multi-target system, including lessons learned, tools developed, technologies explored, and a description of current capability.« less
DOT National Transportation Integrated Search
2004-10-01
The parking assistance system evaluated consisted of four outward facing cameras whose images could be presented on a monitor on the center console. The images presented varied in the location of the virtual eye point of the camera (the height above ...
Design and Development of Multi-Purpose CCD Camera System with Thermoelectric Cooling: Hardware
NASA Astrophysics Data System (ADS)
Kang, Y.-W.; Byun, Y. I.; Rhee, J. H.; Oh, S. H.; Kim, D. K.
2007-12-01
We designed and developed a multi-purpose CCD camera system for three kinds of CCDs; KAF-0401E(768×512), KAF-1602E(1536×1024), KAF-3200E(2184×1472) made by KODAK Co.. The system supports fast USB port as well as parallel port for data I/O and control signal. The packing is based on two stage circuit boards for size reduction and contains built-in filter wheel. Basic hardware components include clock pattern circuit, A/D conversion circuit, CCD data flow control circuit, and CCD temperature control unit. The CCD temperature can be controlled with accuracy of approximately 0.4° C in the max. range of temperature, Δ 33° C. This CCD camera system has with readout noise 6 e^{-}, and system gain 5 e^{-}/ADU. A total of 10 CCD camera systems were produced and our tests show that all of them show passable performance.
A simple method to achieve full-field and real-scale reconstruction using a movable stereo rig
NASA Astrophysics Data System (ADS)
Gu, Feifei; Zhao, Hong; Song, Zhan; Tang, Suming
2018-06-01
This paper introduces a simple method to achieve full-field and real-scale reconstruction using a movable binocular vision system (MBVS). The MBVS is composed of two cameras, one is called the tracking camera, and the other is called the working camera. The tracking camera is used for tracking the positions of the MBVS and the working camera is used for the 3D reconstruction task. The MBVS has several advantages compared with a single moving camera or multi-camera networks. Firstly, the MBVS could recover the real-scale-depth-information from the captured image sequences without using auxiliary objects whose geometry or motion should be precisely known. Secondly, the removability of the system could guarantee appropriate baselines to supply more robust point correspondences. Additionally, using one camera could avoid the drawback which exists in multi-camera networks, that the variability of a cameras’ parameters and performance could significantly affect the accuracy and robustness of the feature extraction and stereo matching methods. The proposed framework consists of local reconstruction and initial pose estimation of the MBVS based on transferable features, followed by overall optimization and accurate integration of multi-view 3D reconstruction data. The whole process requires no information other than the input images. The framework has been verified with real data, and very good results have been obtained.
NASA Astrophysics Data System (ADS)
Pattke, Marco; Martin, Manuel; Voit, Michael
2017-05-01
Tracking people with cameras in public areas is common today. However with an increasing number of cameras it becomes harder and harder to view the data manually. Especially in safety critical areas automatic image exploitation could help to solve this problem. Setting up such a system can however be difficult because of its increased complexity. Sensor placement is critical to ensure that people are detected and tracked reliably. We try to solve this problem using a simulation framework that is able to simulate different camera setups in the desired environment including animated characters. We combine this framework with our self developed distributed and scalable system for people tracking to test its effectiveness and can show the results of the tracking system in real time in the simulated environment.
Investigation of Parallax Issues for Multi-Lens Multispectral Camera Band Co-Registration
NASA Astrophysics Data System (ADS)
Jhan, J. P.; Rau, J. Y.; Haala, N.; Cramer, M.
2017-08-01
The multi-lens multispectral cameras (MSCs), such as Micasense Rededge and Parrot Sequoia, can record multispectral information by each separated lenses. With their lightweight and small size, which making they are more suitable for mounting on an Unmanned Aerial System (UAS) to collect high spatial images for vegetation investigation. However, due to the multi-sensor geometry of multi-lens structure induces significant band misregistration effects in original image, performing band co-registration is necessary in order to obtain accurate spectral information. A robust and adaptive band-to-band image transform (RABBIT) is proposed to perform band co-registration of multi-lens MSCs. First is to obtain the camera rig information from camera system calibration, and utilizes the calibrated results for performing image transformation and lens distortion correction. Since the calibration uncertainty leads to different amount of systematic errors, the last step is to optimize the results in order to acquire a better co-registration accuracy. Due to the potential issues of parallax that will cause significant band misregistration effects when images are closer to the targets, four datasets thus acquired from Rededge and Sequoia were applied to evaluate the performance of RABBIT, including aerial and close-range imagery. From the results of aerial images, it shows that RABBIT can achieve sub-pixel accuracy level that is suitable for the band co-registration purpose of any multi-lens MSC. In addition, the results of close-range images also has same performance, if we focus on the band co-registration on specific target for 3D modelling, or when the target has equal distance to the camera.
Sevrin, Loïc; Noury, Norbert; Abouchi, Nacer; Jumel, Fabrice; Massot, Bertrand; Saraydaryan, Jacques
2015-01-01
An increasing number of systems use indoor positioning for many scenarios such as asset tracking, health care, games, manufacturing, logistics, shopping, and security. Many technologies are available and the use of depth cameras is becoming more and more attractive as this kind of device becomes affordable and easy to handle. This paper contributes to the effort of creating an indoor positioning system based on low cost depth cameras (Kinect). A method is proposed to optimize the calibration of the depth cameras, to describe the multi-camera data fusion and to specify a global positioning projection to maintain the compatibility with outdoor positioning systems. The monitoring of the people trajectories at home is intended for the early detection of a shift in daily activities which highlights disabilities and loss of autonomy. This system is meant to improve homecare health management at home for a better end of life at a sustainable cost for the community.
NASA Astrophysics Data System (ADS)
Zoletnik, S.; Biedermann, C.; Cseh, G.; Kocsis, G.; König, R.; Szabolics, T.; Szepesi, T.; Wendelstein 7-X Team
2018-01-01
A special video camera has been developed for the 10-camera overview video system of the Wendelstein 7-X (W7-X) stellarator considering multiple application needs and limitations resulting from this complex long-pulse superconducting stellarator experiment. The event detection intelligent camera (EDICAM) uses a special 1.3 Mpixel CMOS sensor with non-destructive read capability which enables fast monitoring of smaller Regions of Interest (ROIs) even during long exposures. The camera can perform simple data evaluation algorithms (minimum/maximum, mean comparison to levels) on the ROI data which can dynamically change the readout process and generate output signals. Multiple EDICAM cameras were operated in the first campaign of W7-X and capabilities were explored in the real environment. Data prove that the camera can be used for taking long exposure (10-100 ms) overview images of the plasma while sub-ms monitoring and even multi-camera correlated edge plasma turbulence measurements of smaller areas can be done in parallel. These latter revealed that filamentary turbulence structures extend between neighboring modules of the stellarator. Considerations emerging for future upgrades of this system and similar setups on future long-pulse fusion experiments such as ITER are discussed.
Multi-camera sensor system for 3D segmentation and localization of multiple mobile robots.
Losada, Cristina; Mazo, Manuel; Palazuelos, Sira; Pizarro, Daniel; Marrón, Marta
2010-01-01
This paper presents a method for obtaining the motion segmentation and 3D localization of multiple mobile robots in an intelligent space using a multi-camera sensor system. The set of calibrated and synchronized cameras are placed in fixed positions within the environment (intelligent space). The proposed algorithm for motion segmentation and 3D localization is based on the minimization of an objective function. This function includes information from all the cameras, and it does not rely on previous knowledge or invasive landmarks on board the robots. The proposed objective function depends on three groups of variables: the segmentation boundaries, the motion parameters and the depth. For the objective function minimization, we use a greedy iterative algorithm with three steps that, after initialization of segmentation boundaries and depth, are repeated until convergence.
Multiview face detection based on position estimation over multicamera surveillance system
NASA Astrophysics Data System (ADS)
Huang, Ching-chun; Chou, Jay; Shiu, Jia-Hou; Wang, Sheng-Jyh
2012-02-01
In this paper, we propose a multi-view face detection system that locates head positions and indicates the direction of each face in 3-D space over a multi-camera surveillance system. To locate 3-D head positions, conventional methods relied on face detection in 2-D images and projected the face regions back to 3-D space for correspondence. However, the inevitable false face detection and rejection usually degrades the system performance. Instead, our system searches for the heads and face directions over the 3-D space using a sliding cube. Each searched 3-D cube is projected onto the 2-D camera views to determine the existence and direction of human faces. Moreover, a pre-process to estimate the locations of candidate targets is illustrated to speed-up the searching process over the 3-D space. In summary, our proposed method can efficiently fuse multi-camera information and suppress the ambiguity caused by detection errors. Our evaluation shows that the proposed approach can efficiently indicate the head position and face direction on real video sequences even under serious occlusion.
A multi-criteria approach to camera motion design for volume data animation.
Hsu, Wei-Hsien; Zhang, Yubo; Ma, Kwan-Liu
2013-12-01
We present an integrated camera motion design and path generation system for building volume data animations. Creating animations is an essential task in presenting complex scientific visualizations. Existing visualization systems use an established animation function based on keyframes selected by the user. This approach is limited in providing the optimal in-between views of the data. Alternatively, computer graphics and virtual reality camera motion planning is frequently focused on collision free movement in a virtual walkthrough. For semi-transparent, fuzzy, or blobby volume data the collision free objective becomes insufficient. Here, we provide a set of essential criteria focused on computing camera paths to establish effective animations of volume data. Our dynamic multi-criteria solver coupled with a force-directed routing algorithm enables rapid generation of camera paths. Once users review the resulting animation and evaluate the camera motion, they are able to determine how each criterion impacts path generation. In this paper, we demonstrate how incorporating this animation approach with an interactive volume visualization system reduces the effort in creating context-aware and coherent animations. This frees the user to focus on visualization tasks with the objective of gaining additional insight from the volume data.
Multi-Angle Snowflake Camera Value-Added Product
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shkurko, Konstantin; Garrett, T.; Gaustad, K
The Multi-Angle Snowflake Camera (MASC) addresses a need for high-resolution multi-angle imaging of hydrometeors in freefall with simultaneous measurement of fallspeed. As illustrated in Figure 1, the MASC consists of three cameras, separated by 36°, each pointing at an identical focal point approximately 10 cm away. Located immediately above each camera, a light aims directly at the center of depth of field for its corresponding camera. The focal point at which the cameras are aimed lies within a ring through which hydrometeors fall. The ring houses a system of near-infrared emitter-detector pairs, arranged in two arrays separated vertically by 32more » mm. When hydrometeors pass through the lower array, they simultaneously trigger all cameras and lights. Fallspeed is calculated from the time it takes to traverse the distance between the upper and lower triggering arrays. The trigger electronics filter out ambient light fluctuations associated with varying sunlight and shadows. The microprocessor onboard the MASC controls the camera system and communicates with the personal computer (PC). The image data is sent via FireWire 800 line, and fallspeed (and camera control) is sent via a Universal Serial Bus (USB) line that relies on RS232-over-USB serial conversion. See Table 1 for specific details on the MASC located at the Oliktok Point Mobile Facility on the North Slope of Alaska. The value-added product (VAP) detailed in this documentation analyzes the raw data (Section 2.0) using Python: images rely on OpenCV image processing library and derived aggregated statistics rely on some clever averaging. See Sections 4.1 and 4.2 for more details on what variables are computed.« less
A Framework for People Re-Identification in Multi-Camera Surveillance Systems
ERIC Educational Resources Information Center
Ammar, Sirine; Zaghden, Nizar; Neji, Mahmoud
2017-01-01
People re-identification has been a very active research topic recently in computer vision. It is an important application in surveillance system with disjoint cameras. This paper is focused on the implementation of a human re-identification system. First the face of detected people is divided into three parts and some soft-biometric traits are…
Numerical analysis of wavefront measurement characteristics by using plenoptic camera
NASA Astrophysics Data System (ADS)
Lv, Yang; Ma, Haotong; Zhang, Xuanzhe; Ning, Yu; Xu, Xiaojun
2016-01-01
To take advantage of the large-diameter telescope for high-resolution imaging of extended targets, it is necessary to detect and compensate the wave-front aberrations induced by atmospheric turbulence. Data recorded by Plenoptic cameras can be used to extract the wave-front phases associated to the atmospheric turbulence in an astronomical observation. In order to recover the wave-front phase tomographically, a method of completing the large Field Of View (FOV), multi-perspective wave-front detection simultaneously is urgently demanded, and it is plenoptic camera that possesses this unique advantage. Our paper focuses more on the capability of plenoptic camera to extract the wave-front from different perspectives simultaneously. In this paper, we built up the corresponding theoretical model and simulation system to discuss wave-front measurement characteristics utilizing plenoptic camera as wave-front sensor. And we evaluated the performance of plenoptic camera with different types of wave-front aberration corresponding to the occasions of applications. In the last, we performed the multi-perspective wave-front sensing employing plenoptic camera as wave-front sensor in the simulation. Our research of wave-front measurement characteristics employing plenoptic camera is helpful to select and design the parameters of a plenoptic camera, when utilizing which as multi-perspective and large FOV wave-front sensor, which is expected to solve the problem of large FOV wave-front detection, and can be used for AO in giant telescopes.
Robust and adaptive band-to-band image transform of UAS miniature multi-lens multispectral camera
NASA Astrophysics Data System (ADS)
Jhan, Jyun-Ping; Rau, Jiann-Yeou; Haala, Norbert
2018-03-01
Utilizing miniature multispectral (MS) or hyperspectral (HS) cameras by mounting them on an Unmanned Aerial System (UAS) has the benefits of convenience and flexibility to collect remote sensing imagery for precision agriculture, vegetation monitoring, and environment investigation applications. Most miniature MS cameras adopt a multi-lens structure to record discrete MS bands of visible and invisible information. The differences in lens distortion, mounting positions, and viewing angles among lenses mean that the acquired original MS images have significant band misregistration errors. We have developed a Robust and Adaptive Band-to-Band Image Transform (RABBIT) method for dealing with the band co-registration of various types of miniature multi-lens multispectral cameras (Mini-MSCs) to obtain band co-registered MS imagery for remote sensing applications. The RABBIT utilizes modified projective transformation (MPT) to transfer the multiple image geometry of a multi-lens imaging system to one sensor geometry, and combines this with a robust and adaptive correction (RAC) procedure to correct several systematic errors and to obtain sub-pixel accuracy. This study applies three state-of-the-art Mini-MSCs to evaluate the RABBIT method's performance, specifically the Tetracam Miniature Multiple Camera Array (MiniMCA), Micasense RedEdge, and Parrot Sequoia. Six MS datasets acquired at different target distances and dates, and locations are also applied to prove its reliability and applicability. Results prove that RABBIT is feasible for different types of Mini-MSCs with accurate, robust, and rapid image processing efficiency.
High-accuracy 3D measurement system based on multi-view and structured light
NASA Astrophysics Data System (ADS)
Li, Mingyue; Weng, Dongdong; Li, Yufeng; Zhang, Longbin; Zhou, Haiyun
2013-12-01
3D surface reconstruction is one of the most important topics in Spatial Augmented Reality (SAR). Using structured light is a simple and rapid method to reconstruct the objects. In order to improve the precision of 3D reconstruction, we present a high-accuracy multi-view 3D measurement system based on Gray-code and Phase-shift. We use a camera and a light projector that casts structured light patterns on the objects. In this system, we use only one camera to take photos on the left and right sides of the object respectively. In addition, we use VisualSFM to process the relationships between each perspective, so the camera calibration can be omitted and the positions to place the camera are no longer limited. We also set appropriate exposure time to make the scenes covered by gray-code patterns more recognizable. All of the points above make the reconstruction more precise. We took experiments on different kinds of objects, and a large number of experimental results verify the feasibility and high accuracy of the system.
Automatic Orientation of Large Blocks of Oblique Images
NASA Astrophysics Data System (ADS)
Rupnik, E.; Nex, F.; Remondino, F.
2013-05-01
Nowadays, multi-camera platforms combining nadir and oblique cameras are experiencing a revival. Due to their advantages such as ease of interpretation, completeness through mitigation of occluding areas, as well as system accessibility, they have found their place in numerous civil applications. However, automatic post-processing of such imagery still remains a topic of research. Configuration of cameras poses a challenge on the traditional photogrammetric pipeline used in commercial software and manual measurements are inevitable. For large image blocks it is certainly an impediment. Within theoretical part of the work we review three common least square adjustment methods and recap on possible ways for a multi-camera system orientation. In the practical part we present an approach that successfully oriented a block of 550 images acquired with an imaging system composed of 5 cameras (Canon Eos 1D Mark III) with different focal lengths. Oblique cameras are rotated in the four looking directions (forward, backward, left and right) by 45° with respect to the nadir camera. The workflow relies only upon open-source software: a developed tool to analyse image connectivity and Apero to orient the image block. The benefits of the connectivity tool are twofold: in terms of computational time and success of Bundle Block Adjustment. It exploits the georeferenced information provided by the Applanix system in constraining feature point extraction to relevant images only, and guides the concatenation of images during the relative orientation. Ultimately an absolute transformation is performed resulting in mean re-projection residuals equal to 0.6 pix.
LAMOST CCD camera-control system based on RTS2
NASA Astrophysics Data System (ADS)
Tian, Yuan; Wang, Zheng; Li, Jian; Cao, Zi-Huang; Dai, Wei; Wei, Shou-Lin; Zhao, Yong-Heng
2018-05-01
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) is the largest existing spectroscopic survey telescope, having 32 scientific charge-coupled-device (CCD) cameras for acquiring spectra. Stability and automation of the camera-control software are essential, but cannot be provided by the existing system. The Remote Telescope System 2nd Version (RTS2) is an open-source and automatic observatory-control system. However, all previous RTS2 applications were developed for small telescopes. This paper focuses on implementation of an RTS2-based camera-control system for the 32 CCDs of LAMOST. A virtual camera module inherited from the RTS2 camera module is built as a device component working on the RTS2 framework. To improve the controllability and robustness, a virtualized layer is designed using the master-slave software paradigm, and the virtual camera module is mapped to the 32 real cameras of LAMOST. The new system is deployed in the actual environment and experimentally tested. Finally, multiple observations are conducted using this new RTS2-framework-based control system. The new camera-control system is found to satisfy the requirements for automatic camera control in LAMOST. This is the first time that RTS2 has been applied to a large telescope, and provides a referential solution for full RTS2 introduction to the LAMOST observatory control system.
Zhang, Cuicui; Liang, Xuefeng; Matsuyama, Takashi
2014-12-08
Multi-camera networks have gained great interest in video-based surveillance systems for security monitoring, access control, etc. Person re-identification is an essential and challenging task in multi-camera networks, which aims to determine if a given individual has already appeared over the camera network. Individual recognition often uses faces as a trial and requires a large number of samples during the training phrase. This is difficult to fulfill due to the limitation of the camera hardware system and the unconstrained image capturing conditions. Conventional face recognition algorithms often encounter the "small sample size" (SSS) problem arising from the small number of training samples compared to the high dimensionality of the sample space. To overcome this problem, interest in the combination of multiple base classifiers has sparked research efforts in ensemble methods. However, existing ensemble methods still open two questions: (1) how to define diverse base classifiers from the small data; (2) how to avoid the diversity/accuracy dilemma occurring during ensemble. To address these problems, this paper proposes a novel generic learning-based ensemble framework, which augments the small data by generating new samples based on a generic distribution and introduces a tailored 0-1 knapsack algorithm to alleviate the diversity/accuracy dilemma. More diverse base classifiers can be generated from the expanded face space, and more appropriate base classifiers are selected for ensemble. Extensive experimental results on four benchmarks demonstrate the higher ability of our system to cope with the SSS problem compared to the state-of-the-art system.
Zhang, Cuicui; Liang, Xuefeng; Matsuyama, Takashi
2014-01-01
Multi-camera networks have gained great interest in video-based surveillance systems for security monitoring, access control, etc. Person re-identification is an essential and challenging task in multi-camera networks, which aims to determine if a given individual has already appeared over the camera network. Individual recognition often uses faces as a trial and requires a large number of samples during the training phrase. This is difficult to fulfill due to the limitation of the camera hardware system and the unconstrained image capturing conditions. Conventional face recognition algorithms often encounter the “small sample size” (SSS) problem arising from the small number of training samples compared to the high dimensionality of the sample space. To overcome this problem, interest in the combination of multiple base classifiers has sparked research efforts in ensemble methods. However, existing ensemble methods still open two questions: (1) how to define diverse base classifiers from the small data; (2) how to avoid the diversity/accuracy dilemma occurring during ensemble. To address these problems, this paper proposes a novel generic learning-based ensemble framework, which augments the small data by generating new samples based on a generic distribution and introduces a tailored 0–1 knapsack algorithm to alleviate the diversity/accuracy dilemma. More diverse base classifiers can be generated from the expanded face space, and more appropriate base classifiers are selected for ensemble. Extensive experimental results on four benchmarks demonstrate the higher ability of our system to cope with the SSS problem compared to the state-of-the-art system. PMID:25494350
Ground-based search for the brightest transiting planets with the Multi-site All-Sky CAmeRA: MASCARA
NASA Astrophysics Data System (ADS)
Snellen, Ignas A. G.; Stuik, Remko; Navarro, Ramon; Bettonvil, Felix; Kenworthy, Matthew; de Mooij, Ernst; Otten, Gilles; ter Horst, Rik; le Poole, Rudolf
2012-09-01
The Multi-site All-sky CAmeRA MASCARA is an instrument concept consisting of several stations across the globe, with each station containing a battery of low-cost cameras to monitor the near-entire sky at each location. Once all stations have been installed, MASCARA will be able to provide a nearly 24-hr coverage of the complete dark sky, down to magnitude 8, at sub-minute cadence. Its purpose is to find the brightest transiting exoplanet systems, expected in the V=4-8 magnitude range - currently not probed by space- or ground-based surveys. The bright/nearby transiting planet systems, which MASCARA will discover, will be the key targets for detailed planet atmosphere observations. We present studies on the initial design of a MASCARA station, including the camera housing, domes, and computer equipment, and on the photometric stability of low-cost cameras showing that a precision of 0.3-1% per hour can be readily achieved. We plan to roll out the first MASCARA station before the end of 2013. A 5-station MASCARA can within two years discover up to a dozen of the brightest transiting planet systems in the sky.
NASA Astrophysics Data System (ADS)
Terzopoulos, Demetri; Qureshi, Faisal Z.
Computer vision and sensor networks researchers are increasingly motivated to investigate complex multi-camera sensing and control issues that arise in the automatic visual surveillance of extensive, highly populated public spaces such as airports and train stations. However, they often encounter serious impediments to deploying and experimenting with large-scale physical camera networks in such real-world environments. We propose an alternative approach called "Virtual Vision", which facilitates this type of research through the virtual reality simulation of populated urban spaces, camera sensor networks, and computer vision on commodity computers. We demonstrate the usefulness of our approach by developing two highly automated surveillance systems comprising passive and active pan/tilt/zoom cameras that are deployed in a virtual train station environment populated by autonomous, lifelike virtual pedestrians. The easily reconfigurable virtual cameras distributed in this environment generate synthetic video feeds that emulate those acquired by real surveillance cameras monitoring public spaces. The novel multi-camera control strategies that we describe enable the cameras to collaborate in persistently observing pedestrians of interest and in acquiring close-up videos of pedestrians in designated areas.
Aerial multi-camera systems: Accuracy and block triangulation issues
NASA Astrophysics Data System (ADS)
Rupnik, Ewelina; Nex, Francesco; Toschi, Isabella; Remondino, Fabio
2015-03-01
Oblique photography has reached its maturity and has now been adopted for several applications. The number and variety of multi-camera oblique platforms available on the market is continuously growing. So far, few attempts have been made to study the influence of the additional cameras on the behaviour of the image block and comprehensive revisions to existing flight patterns are yet to be formulated. This paper looks into the precision and accuracy of 3D points triangulated from diverse multi-camera oblique platforms. Its coverage is divided into simulated and real case studies. Within the simulations, different imaging platform parameters and flight patterns are varied, reflecting both current market offerings and common flight practices. Attention is paid to the aspect of completeness in terms of dense matching algorithms and 3D city modelling - the most promising application of such systems. The experimental part demonstrates the behaviour of two oblique imaging platforms in real-world conditions. A number of Ground Control Point (GCP) configurations are adopted in order to point out the sensitivity of tested imaging networks and arising block deformations. To stress the contribution of slanted views, all scenarios are compared against a scenario in which exclusively nadir images are used for evaluation.
Calibration Method for IATS and Application in Multi-Target Monitoring Using Coded Targets
NASA Astrophysics Data System (ADS)
Zhou, Yueyin; Wagner, Andreas; Wunderlich, Thomas; Wasmeier, Peter
2017-06-01
The technique of Image Assisted Total Stations (IATS) has been studied for over ten years and is composed of two major parts: one is the calibration procedure which combines the relationship between the camera system and the theodolite system; the other is the automatic target detection on the image by various methods of photogrammetry or computer vision. Several calibration methods have been developed, mostly using prototypes with an add-on camera rigidly mounted on the total station. However, these prototypes are not commercially available. This paper proposes a calibration method based on Leica MS50 which has two built-in cameras each with a resolution of 2560 × 1920 px: an overview camera and a telescope (on-axis) camera. Our work in this paper is based on the on-axis camera which uses the 30-times magnification of the telescope. The calibration consists of 7 parameters to estimate. We use coded targets, which are common tools in photogrammetry for orientation, to detect different targets in IATS images instead of prisms and traditional ATR functions. We test and verify the efficiency and stability of this monitoring method with multi-target.
Falling-incident detection and throughput enhancement in a multi-camera video-surveillance system.
Shieh, Wann-Yun; Huang, Ju-Chin
2012-09-01
For most elderly, unpredictable falling incidents may occur at the corner of stairs or a long corridor due to body frailty. If we delay to rescue a falling elder who is likely fainting, more serious consequent injury may occur. Traditional secure or video surveillance systems need caregivers to monitor a centralized screen continuously, or need an elder to wear sensors to detect falling incidents, which explicitly waste much human power or cause inconvenience for elders. In this paper, we propose an automatic falling-detection algorithm and implement this algorithm in a multi-camera video surveillance system. The algorithm uses each camera to fetch the images from the regions required to be monitored. It then uses a falling-pattern recognition algorithm to determine if a falling incident has occurred. If yes, system will send short messages to someone needs to be noticed. The algorithm has been implemented in a DSP-based hardware acceleration board for functionality proof. Simulation results show that the accuracy of falling detection can achieve at least 90% and the throughput of a four-camera surveillance system can be improved by about 2.1 times. Copyright © 2011 IPEM. Published by Elsevier Ltd. All rights reserved.
Concave Surround Optics for Rapid Multi-View Imaging
2006-11-01
thus is amenable to capturing dynamic events avoiding the need to construct and calibrate an array of cameras. We demonstrate the system with a high...hard to assemble and calibrate . In this paper we present an optical system capable of rapidly moving the viewpoint around a scene. Our system...flexibility, large camera arrays are typically expensive and require significant effort to calibrate temporally, geometrically and chromatically
Development of a real time multiple target, multi camera tracker for civil security applications
NASA Astrophysics Data System (ADS)
Åkerlund, Hans
2009-09-01
A surveillance system has been developed that can use multiple TV-cameras to detect and track personnel and objects in real time in public areas. The document describes the development and the system setup. The system is called NIVS Networked Intelligent Video Surveillance. Persons in the images are tracked and displayed on a 3D map of the surveyed area.
New Modular Camera No Ordinary Joe
NASA Technical Reports Server (NTRS)
2003-01-01
Although dubbed 'Little Joe' for its small-format characteristics, a new wavefront sensor camera has proved that it is far from coming up short when paired with high-speed, low-noise applications. SciMeasure Analytical Systems, Inc., a provider of cameras and imaging accessories for use in biomedical research and industrial inspection and quality control, is the eye behind Little Joe's shutter, manufacturing and selling the modular, multi-purpose camera worldwide to advance fields such as astronomy, neurobiology, and cardiology.
NASA Astrophysics Data System (ADS)
Kirby, Richard; Whitaker, Ross
2016-09-01
In recent years, the use of multi-modal camera rigs consisting of an RGB sensor and an infrared (IR) sensor have become increasingly popular for use in surveillance and robotics applications. The advantages of using multi-modal camera rigs include improved foreground/background segmentation, wider range of lighting conditions under which the system works, and richer information (e.g. visible light and heat signature) for target identification. However, the traditional computer vision method of mapping pairs of images using pixel intensities or image features is often not possible with an RGB/IR image pair. We introduce a novel method to overcome the lack of common features in RGB/IR image pairs by using a variational methods optimization algorithm to map the optical flow fields computed from different wavelength images. This results in the alignment of the flow fields, which in turn produce correspondences similar to those found in a stereo RGB/RGB camera rig using pixel intensities or image features. In addition to aligning the different wavelength images, these correspondences are used to generate dense disparity and depth maps. We obtain accuracies similar to other multi-modal image alignment methodologies as long as the scene contains sufficient depth variations, although a direct comparison is not possible because of the lack of standard image sets from moving multi-modal camera rigs. We test our method on synthetic optical flow fields and on real image sequences that we created with a multi-modal binocular stereo RGB/IR camera rig. We determine our method's accuracy by comparing against a ground truth.
Multi-pinhole collimator design for small-object imaging with SiliSPECT: a high-resolution SPECT
NASA Astrophysics Data System (ADS)
Shokouhi, S.; Metzler, S. D.; Wilson, D. W.; Peterson, T. E.
2009-01-01
We have designed a multi-pinhole collimator for a dual-headed, stationary SPECT system that incorporates high-resolution silicon double-sided strip detectors. The compact camera design of our system enables imaging at source-collimator distances between 20 and 30 mm. Our analytical calculations show that using knife-edge pinholes with small-opening angles or cylindrically shaped pinholes in a focused, multi-pinhole configuration in combination with this camera geometry can generate narrow sensitivity profiles across the field of view that can be useful for imaging small objects at high sensitivity and resolution. The current prototype system uses two collimators each containing 127 cylindrically shaped pinholes that are focused toward a target volume. Our goal is imaging objects such as a mouse brain, which could find potential applications in molecular imaging.
NASA Astrophysics Data System (ADS)
Neukum, Gerhard; Jaumann, Ralf; Scholten, Frank; Gwinner, Klaus
2017-11-01
At the Institute of Space Sensor Technology and Planetary Exploration of the German Aerospace Center (DLR) the High Resolution Stereo Camera (HRSC) has been designed for international missions to planet Mars. For more than three years an airborne version of this camera, the HRSC-A, has been successfully applied in many flight campaigns and in a variety of different applications. It combines 3D-capabilities and high resolution with multispectral data acquisition. Variable resolutions depending on the camera control settings can be generated. A high-end GPS/INS system in combination with the multi-angle image information yields precise and high-frequent orientation data for the acquired image lines. In order to handle these data a completely automated photogrammetric processing system has been developed, and allows to generate multispectral 3D-image products for large areas and with accuracies for planimetry and height in the decimeter range. This accuracy has been confirmed by detailed investigations.
Canedo-Rodriguez, Adrián; Iglesias, Roberto; Regueiro, Carlos V.; Alvarez-Santos, Victor; Pardo, Xose Manuel
2013-01-01
To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposal. PMID:23271604
Canedo-Rodriguez, Adrián; Iglesias, Roberto; Regueiro, Carlos V; Alvarez-Santos, Victor; Pardo, Xose Manuel
2012-12-27
To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposal.
Visual tracking for multi-modality computer-assisted image guidance
NASA Astrophysics Data System (ADS)
Basafa, Ehsan; Foroughi, Pezhman; Hossbach, Martin; Bhanushali, Jasmine; Stolka, Philipp
2017-03-01
With optical cameras, many interventional navigation tasks previously relying on EM, optical, or mechanical guidance can be performed robustly, quickly, and conveniently. We developed a family of novel guidance systems based on wide-spectrum cameras and vision algorithms for real-time tracking of interventional instruments and multi-modality markers. These navigation systems support the localization of anatomical targets, support placement of imaging probe and instruments, and provide fusion imaging. The unique architecture - low-cost, miniature, in-hand stereo vision cameras fitted directly to imaging probes - allows for an intuitive workflow that fits a wide variety of specialties such as anesthesiology, interventional radiology, interventional oncology, emergency medicine, urology, and others, many of which see increasing pressure to utilize medical imaging and especially ultrasound, but have yet to develop the requisite skills for reliable success. We developed a modular system, consisting of hardware (the Optical Head containing the mini cameras) and software (components for visual instrument tracking with or without specialized visual features, fully automated marker segmentation from a variety of 3D imaging modalities, visual observation of meshes of widely separated markers, instant automatic registration, and target tracking and guidance on real-time multi-modality fusion views). From these components, we implemented a family of distinct clinical and pre-clinical systems (for combinations of ultrasound, CT, CBCT, and MRI), most of which have international regulatory clearance for clinical use. We present technical and clinical results on phantoms, ex- and in-vivo animals, and patients.
Kottner, Sören; Ebert, Lars C; Ampanozi, Garyfalia; Braun, Marcel; Thali, Michael J; Gascho, Dominic
2017-03-01
Injuries such as bite marks or boot prints can leave distinct patterns on the body's surface and can be used for 3D reconstructions. Although various systems for 3D surface imaging have been introduced in the forensic field, most techniques are both cost-intensive and time-consuming. In this article, we present the VirtoScan, a mobile, multi-camera rig based on close-range photogrammetry. The system can be integrated into automated PMCT scanning procedures or used manually together with lifting carts, autopsy tables and examination couch. The VirtoScan is based on a moveable frame that carries 7 digital single-lens reflex cameras. A remote control is attached to each camera and allows the simultaneous triggering of the shutter release of all cameras. Data acquisition in combination with the PMCT scanning procedures took 3:34 min for the 3D surface documentation of one side of the body compared to 20:20 min of acquisition time when using our in-house standard. A surface model comparison between the high resolution output from our in-house standard and a high resolution model from the multi-camera rig showed a mean surface deviation of 0.36 mm for the whole body scan and 0.13 mm for a second comparison of a detailed section of the scan. The use of the multi-camera rig reduces the acquisition time for whole-body surface documentations in medico-legal examinations and provides a low-cost 3D surface scanning alternative for forensic investigations.
Cooperative multisensor system for real-time face detection and tracking in uncontrolled conditions
NASA Astrophysics Data System (ADS)
Marchesotti, Luca; Piva, Stefano; Turolla, Andrea; Minetti, Deborah; Regazzoni, Carlo S.
2005-03-01
The presented work describes an innovative architecture for multi-sensor distributed video surveillance applications. The aim of the system is to track moving objects in outdoor environments with a cooperative strategy exploiting two video cameras. The system also exhibits the capacity of focusing its attention on the faces of detected pedestrians collecting snapshot frames of face images, by segmenting and tracking them over time at different resolution. The system is designed to employ two video cameras in a cooperative client/server structure: the first camera monitors the entire area of interest and detects the moving objects using change detection techniques. The detected objects are tracked over time and their position is indicated on a map representing the monitored area. The objects" coordinates are sent to the server sensor in order to point its zooming optics towards the moving object. The second camera tracks the objects at high resolution. As well as the client camera, this sensor is calibrated and the position of the object detected on the image plane reference system is translated in its coordinates referred to the same area map. In the map common reference system, data fusion techniques are applied to achieve a more precise and robust estimation of the objects" track and to perform face detection and tracking. The work novelties and strength reside in the cooperative multi-sensor approach, in the high resolution long distance tracking and in the automatic collection of biometric data such as a person face clip for recognition purposes.
Preliminary Evaluation of a Commercial 360 Multi-Camera Rig for Photogrammetric Purposes
NASA Astrophysics Data System (ADS)
Teppati Losè, L.; Chiabrando, F.; Spanò, A.
2018-05-01
The research presented in this paper is focused on a preliminary evaluation of a 360 multi-camera rig: the possibilities to use the images acquired by the system in a photogrammetric workflow and for the creation of spherical images are investigated and different tests and analyses are reported. Particular attention is dedicated to different operative approaches for the estimation of the interior orientation parameters of the cameras, both from an operative and theoretical point of view. The consistency of the six cameras that compose the 360 system was in depth analysed adopting a self-calibration approach in a commercial photogrammetric software solution. A 3D calibration field was projected and created, and several topographic measurements were performed in order to have a set of control points to enhance and control the photogrammetric process. The influence of the interior parameters of the six cameras were analyse both in the different phases of the photogrammetric workflow (reprojection errors on the single tie point, dense cloud generation, geometrical description of the surveyed object, etc.), both in the stitching of the different images into a single spherical panorama (some consideration on the influence of the camera parameters on the overall quality of the spherical image are reported also in these section).
Multi-spectral imaging with infrared sensitive organic light emitting diode
Kim, Do Young; Lai, Tzung-Han; Lee, Jae Woong; Manders, Jesse R.; So, Franky
2014-01-01
Commercially available near-infrared (IR) imagers are fabricated by integrating expensive epitaxial grown III-V compound semiconductor sensors with Si-based readout integrated circuits (ROIC) by indium bump bonding which significantly increases the fabrication costs of these image sensors. Furthermore, these typical III-V compound semiconductors are not sensitive to the visible region and thus cannot be used for multi-spectral (visible to near-IR) sensing. Here, a low cost infrared (IR) imaging camera is demonstrated with a commercially available digital single-lens reflex (DSLR) camera and an IR sensitive organic light emitting diode (IR-OLED). With an IR-OLED, IR images at a wavelength of 1.2 µm are directly converted to visible images which are then recorded in a Si-CMOS DSLR camera. This multi-spectral imaging system is capable of capturing images at wavelengths in the near-infrared as well as visible regions. PMID:25091589
Multi-spectral imaging with infrared sensitive organic light emitting diode
NASA Astrophysics Data System (ADS)
Kim, Do Young; Lai, Tzung-Han; Lee, Jae Woong; Manders, Jesse R.; So, Franky
2014-08-01
Commercially available near-infrared (IR) imagers are fabricated by integrating expensive epitaxial grown III-V compound semiconductor sensors with Si-based readout integrated circuits (ROIC) by indium bump bonding which significantly increases the fabrication costs of these image sensors. Furthermore, these typical III-V compound semiconductors are not sensitive to the visible region and thus cannot be used for multi-spectral (visible to near-IR) sensing. Here, a low cost infrared (IR) imaging camera is demonstrated with a commercially available digital single-lens reflex (DSLR) camera and an IR sensitive organic light emitting diode (IR-OLED). With an IR-OLED, IR images at a wavelength of 1.2 µm are directly converted to visible images which are then recorded in a Si-CMOS DSLR camera. This multi-spectral imaging system is capable of capturing images at wavelengths in the near-infrared as well as visible regions.
2013-09-01
Ground testing of prototype hardware and processing algorithms for a Wide Area Space Surveillance System (WASSS) Neil Goldstein, Rainer A...at Magdalena Ridge Observatory using the prototype Wide Area Space Surveillance System (WASSS) camera, which has a 4 x 60 field-of-view , < 0.05...objects with larger-aperture cameras. The sensitivity of the system depends on multi-frame averaging and a Principal Component Analysis based image
Coincidence ion imaging with a fast frame camera
NASA Astrophysics Data System (ADS)
Lee, Suk Kyoung; Cudry, Fadia; Lin, Yun Fei; Lingenfelter, Steven; Winney, Alexander H.; Fan, Lin; Li, Wen
2014-12-01
A new time- and position-sensitive particle detection system based on a fast frame CMOS (complementary metal-oxide semiconductors) camera is developed for coincidence ion imaging. The system is composed of four major components: a conventional microchannel plate/phosphor screen ion imager, a fast frame CMOS camera, a single anode photomultiplier tube (PMT), and a high-speed digitizer. The system collects the positional information of ions from a fast frame camera through real-time centroiding while the arrival times are obtained from the timing signal of a PMT processed by a high-speed digitizer. Multi-hit capability is achieved by correlating the intensity of ion spots on each camera frame with the peak heights on the corresponding time-of-flight spectrum of a PMT. Efficient computer algorithms are developed to process camera frames and digitizer traces in real-time at 1 kHz laser repetition rate. We demonstrate the capability of this system by detecting a momentum-matched co-fragments pair (methyl and iodine cations) produced from strong field dissociative double ionization of methyl iodide.
Human detection and motion analysis at security points
NASA Astrophysics Data System (ADS)
Ozer, I. Burak; Lv, Tiehan; Wolf, Wayne H.
2003-08-01
This paper presents a real-time video surveillance system for the recognition of specific human activities. Specifically, the proposed automatic motion analysis is used as an on-line alarm system to detect abnormal situations in a campus environment. A smart multi-camera system developed at Princeton University is extended for use in smart environments in which the camera detects the presence of multiple persons as well as their gestures and their interaction in real-time.
Zhang, Yu; Teng, Poching; Shimizu, Yo; Hosoi, Fumiki; Omasa, Kenji
2016-01-01
For plant breeding and growth monitoring, accurate measurements of plant structure parameters are very crucial. We have, therefore, developed a high efficiency Multi-Camera Photography (MCP) system combining Multi-View Stereovision (MVS) with the Structure from Motion (SfM) algorithm. In this paper, we measured six variables of nursery paprika plants and investigated the accuracy of 3D models reconstructed from photos taken by four lens types at four different positions. The results demonstrated that error between the estimated and measured values was small, and the root-mean-square errors (RMSE) for leaf width/length and stem height/diameter were 1.65 mm (R2 = 0.98) and 0.57 mm (R2 = 0.99), respectively. The accuracies of the 3D model reconstruction of leaf and stem by a 28-mm lens at the first and third camera positions were the highest, and the number of reconstructed fine-scale 3D model shape surfaces of leaf and stem is the most. The results confirmed the practicability of our new method for the reconstruction of fine-scale plant model and accurate estimation of the plant parameters. They also displayed that our system is a good system for capturing high-resolution 3D images of nursery plants with high efficiency. PMID:27314348
Multiple-camera tracking: UK government requirements
NASA Astrophysics Data System (ADS)
Hosmer, Paul
2007-10-01
The Imagery Library for Intelligent Detection Systems (i-LIDS) is the UK government's new standard for Video Based Detection Systems (VBDS). The standard was launched in November 2006 and evaluations against it began in July 2007. With the first four i-LIDS scenarios completed, the Home Office Scientific development Branch (HOSDB) are looking toward the future of intelligent vision in the security surveillance market by adding a fifth scenario to the standard. The fifth i-LIDS scenario will concentrate on the development, testing and evaluation of systems for the tracking of people across multiple cameras. HOSDB and the Centre for the Protection of National Infrastructure (CPNI) identified a requirement to track targets across a network of CCTV cameras using both live and post event imagery. The Detection and Vision Systems group at HOSDB were asked to determine the current state of the market and develop an in-depth Operational Requirement (OR) based on government end user requirements. Using this OR the i-LIDS team will develop a full i-LIDS scenario to aid the machine vision community in its development of multi-camera tracking systems. By defining a requirement for multi-camera tracking and building this into the i-LIDS standard the UK government will provide a widely available tool that developers can use to help them turn theory and conceptual demonstrators into front line application. This paper will briefly describe the i-LIDS project and then detail the work conducted in building the new tracking aspect of the standard.
Schlossberg, David J.; Bodner, Grant M.; Bongard, Michael W.; ...
2016-09-16
Here, a novel, cost-effective, multi-point Thomson scattering system has been designed, implemented, and operated on the Pegasus Toroidal Experiment. Leveraging advances in Nd:YAG lasers, high-efficiency volume phase holographic transmission gratings, and increased quantum-efficiency Generation 3 image-intensified charge coupled device (ICCD) cameras, the system provides Thomson spectra at eight spatial locations for a single grating/camera pair. The on-board digitization of the ICCD camera enables easy modular expansion, evidenced by recent extension from 4 to 12 plasma/background spatial location pairs. Stray light is rejected using time-of-flight methods suited to gated ICCDs, and background light is blocked during detector readout by a fastmore » shutter. This –10 3 reduction in background light enables further expansion to up to 24 spatial locations. The implementation now provides single-shot T e(R) for n e > 5 × 10 18 m –3.« less
Polarized fluorescence for skin cancer diagnostic with a multi-aperture camera
NASA Astrophysics Data System (ADS)
Kandimalla, Haripriya; Ramella-Roman, Jessica C.
2008-02-01
Polarized fluorescence has shown some promising results in assessment of skin cancer margins. Researchers have used tetracycline and cross polarization imaging for nonmelanoma skin cancer demarcation as well as investigating endogenous skin polarized fluorescence. In this paper we present a new instrument for polarized fluorescence imaging, able to calculate the full fluorescence Stokes vector in one snapshot. The core of our system is a multi-aperture camera constructed with a two by two lenslet array. Three of the lenses have polarizing elements in front of them, oriented at 0°, + 45°and 90° with respect to light source polarization. A flash lamp combined with a polarizer parallel to the source-camera-sample plane and a UV filter is used as an excitation source. A blue filter in front of the camera system is used to collect only the fluorescent emission of interest and filter out the incident light. In-vitro tests of endogenous and exogenous polarized fluorescence on collagen rich material like bovine tendon were performed and Stokes vector of polarized fluorescence calculated. The system has the advantage of eliminating moving artifacts with the collection of different polarization states and stoke vector in a single snap shot.
FieldSAFE: Dataset for Obstacle Detection in Agriculture.
Kragh, Mikkel Fly; Christiansen, Peter; Laursen, Morten Stigaard; Larsen, Morten; Steen, Kim Arild; Green, Ole; Karstoft, Henrik; Jørgensen, Rasmus Nyholm
2017-11-09
In this paper, we present a multi-modal dataset for obstacle detection in agriculture. The dataset comprises approximately 2 h of raw sensor data from a tractor-mounted sensor system in a grass mowing scenario in Denmark, October 2016. Sensing modalities include stereo camera, thermal camera, web camera, 360 ∘ camera, LiDAR and radar, while precise localization is available from fused IMU and GNSS. Both static and moving obstacles are present, including humans, mannequin dolls, rocks, barrels, buildings, vehicles and vegetation. All obstacles have ground truth object labels and geographic coordinates.
FieldSAFE: Dataset for Obstacle Detection in Agriculture
Christiansen, Peter; Larsen, Morten; Steen, Kim Arild; Green, Ole; Karstoft, Henrik
2017-01-01
In this paper, we present a multi-modal dataset for obstacle detection in agriculture. The dataset comprises approximately 2 h of raw sensor data from a tractor-mounted sensor system in a grass mowing scenario in Denmark, October 2016. Sensing modalities include stereo camera, thermal camera, web camera, 360∘ camera, LiDAR and radar, while precise localization is available from fused IMU and GNSS. Both static and moving obstacles are present, including humans, mannequin dolls, rocks, barrels, buildings, vehicles and vegetation. All obstacles have ground truth object labels and geographic coordinates. PMID:29120383
Development of the SEASIS instrument for SEDSAT
NASA Technical Reports Server (NTRS)
Maier, Mark W.
1996-01-01
Two SEASIS experiment objectives are key: take images that allow three axis attitude determination and take multi-spectral images of the earth. During the tether mission it is also desirable to capture images for the recoiling tether from the endmass perspective (which has never been observed). SEASIS must store all its imagery taken during the tether mission until the earth downlink can be established. SEASIS determines attitude with a panoramic camera and performs earth observation with a telephoto lens camera. Camera video is digitized, compressed, and stored in solid state memory. These objectives are addressed through the following architectural choices: (1) A camera system using a Panoramic Annular Lens (PAL). This lens has a 360 deg. azimuthal field of view by a +45 degree vertical field measured from a plan normal to the lens boresight axis. It has been shown in Mr. Mark Steadham's UAH M.S. thesis that his camera can determine three axis attitude anytime the earth and one other recognizable celestial object (for example, the sun) is in the field of view. This will be essentially all the time during tether deployment. (2) A second camera system using telephoto lens and filter wheel. The camera is a black and white standard video camera. The filters are chosen to cover the visible spectral bands of remote sensing interest. (3) A processor and mass memory arrangement linked to the cameras. Video signals from the cameras are digitized, compressed in the processor, and stored in a large static RAM bank. The processor is a multi-chip module consisting of a T800 Transputer and three Zoran floating point Digital Signal Processors. This processor module was supplied under ARPA contract by the Space Computer Corporation to demonstrate its use in space.
A Novel Multi-Digital Camera System Based on Tilt-Shift Photography Technology
Sun, Tao; Fang, Jun-yong; Zhao, Dong; Liu, Xue; Tong, Qing-xi
2015-01-01
Multi-digital camera systems (MDCS) are constantly being improved to meet the increasing requirement of high-resolution spatial data. This study identifies the insufficiencies of traditional MDCSs and proposes a new category MDCS based on tilt-shift photography to improve ability of the MDCS to acquire high-accuracy spatial data. A prototype system, including two or four tilt-shift cameras (TSC, camera model: Nikon D90), is developed to validate the feasibility and correctness of proposed MDCS. Similar to the cameras of traditional MDCSs, calibration is also essential for TSC of new MDCS. The study constructs indoor control fields and proposes appropriate calibration methods for TSC, including digital distortion model (DDM) approach and two-step calibrated strategy. The characteristics of TSC are analyzed in detail via a calibration experiment; for example, the edge distortion of TSC. Finally, the ability of the new MDCS to acquire high-accuracy spatial data is verified through flight experiments. The results of flight experiments illustrate that geo-position accuracy of prototype system achieves 0.3 m at a flight height of 800 m, and spatial resolution of 0.15 m. In addition, results of the comparison between the traditional (MADC II) and proposed MDCS demonstrate that the latter (0.3 m) provides spatial data with higher accuracy than the former (only 0.6 m) under the same conditions. We also take the attitude that using higher accuracy TSC in the new MDCS should further improve the accuracy of the photogrammetry senior product. PMID:25835187
A novel multi-digital camera system based on tilt-shift photography technology.
Sun, Tao; Fang, Jun-Yong; Zhao, Dong; Liu, Xue; Tong, Qing-Xi
2015-03-31
Multi-digital camera systems (MDCS) are constantly being improved to meet the increasing requirement of high-resolution spatial data. This study identifies the insufficiencies of traditional MDCSs and proposes a new category MDCS based on tilt-shift photography to improve ability of the MDCS to acquire high-accuracy spatial data. A prototype system, including two or four tilt-shift cameras (TSC, camera model: Nikon D90), is developed to validate the feasibility and correctness of proposed MDCS. Similar to the cameras of traditional MDCSs, calibration is also essential for TSC of new MDCS. The study constructs indoor control fields and proposes appropriate calibration methods for TSC, including digital distortion model (DDM) approach and two-step calibrated strategy. The characteristics of TSC are analyzed in detail via a calibration experiment; for example, the edge distortion of TSC. Finally, the ability of the new MDCS to acquire high-accuracy spatial data is verified through flight experiments. The results of flight experiments illustrate that geo-position accuracy of prototype system achieves 0.3 m at a flight height of 800 m, and spatial resolution of 0.15 m. In addition, results of the comparison between the traditional (MADC II) and proposed MDCS demonstrate that the latter (0.3 m) provides spatial data with higher accuracy than the former (only 0.6 m) under the same conditions. We also take the attitude that using higher accuracy TSC in the new MDCS should further improve the accuracy of the photogrammetry senior product.
NASA Astrophysics Data System (ADS)
de Villiers, Jason; Jermy, Robert; Nicolls, Fred
2014-06-01
This paper presents a system to determine the photogrammetric parameters of a camera. The lens distortion, focal length and camera six degree of freedom (DOF) position are calculated. The system caters for cameras of different sensitivity spectra and fields of view without any mechanical modifications. The distortion characterization, a variant of Brown's classic plumb line method, allows many radial and tangential distortion coefficients and finds the optimal principal point. Typical values are 5 radial and 3 tangential coefficients. These parameters are determined stably and demonstrably produce superior results to low order models despite popular and prevalent misconceptions to the contrary. The system produces coefficients to model both the distorted to undistorted pixel coordinate transformation (e.g. for target designation) and the inverse transformation (e.g. for image stitching and fusion) allowing deterministic rates far exceeding real time. The focal length is determined to minimise the error in absolute photogrammetric positional measurement for both multi camera systems or monocular (e.g. helmet tracker) systems. The system determines the 6 DOF position of the camera in a chosen coordinate system. It can also determine the 6 DOF offset of the camera relative to its mechanical mount. This allows faulty cameras to be replaced without requiring a recalibration of the entire system (such as an aircraft cockpit). Results from two simple applications of the calibration results are presented: stitching and fusion of the images from a dual-band visual/ LWIR camera array, and a simple laboratory optical helmet tracker.
Time-Of-Flight Camera, Optical Tracker and Computed Tomography in Pairwise Data Registration.
Pycinski, Bartlomiej; Czajkowska, Joanna; Badura, Pawel; Juszczyk, Jan; Pietka, Ewa
2016-01-01
A growing number of medical applications, including minimal invasive surgery, depends on multi-modal or multi-sensors data processing. Fast and accurate 3D scene analysis, comprising data registration, seems to be crucial for the development of computer aided diagnosis and therapy. The advancement of surface tracking system based on optical trackers already plays an important role in surgical procedures planning. However, new modalities, like the time-of-flight (ToF) sensors, widely explored in non-medical fields are powerful and have the potential to become a part of computer aided surgery set-up. Connection of different acquisition systems promises to provide a valuable support for operating room procedures. Therefore, the detailed analysis of the accuracy of such multi-sensors positioning systems is needed. We present the system combining pre-operative CT series with intra-operative ToF-sensor and optical tracker point clouds. The methodology contains: optical sensor set-up and the ToF-camera calibration procedures, data pre-processing algorithms, and registration technique. The data pre-processing yields a surface, in case of CT, and point clouds for ToF-sensor and marker-driven optical tracker representation of an object of interest. An applied registration technique is based on Iterative Closest Point algorithm. The experiments validate the registration of each pair of modalities/sensors involving phantoms of four various human organs in terms of Hausdorff distance and mean absolute distance metrics. The best surface alignment was obtained for CT and optical tracker combination, whereas the worst for experiments involving ToF-camera. The obtained accuracies encourage to further develop the multi-sensors systems. The presented substantive discussion concerning the system limitations and possible improvements mainly related to the depth information produced by the ToF-sensor is useful for computer aided surgery developers.
Automated generation of image products for Mars Exploration Rover Mission tactical operations
NASA Technical Reports Server (NTRS)
Alexander, Doug; Zamani, Payam; Deen, Robert; Andres, Paul; Mortensen, Helen
2005-01-01
This paper will discuss, from design to implementation, the methodologies applied to MIPL's automated pipeline processing as a 'system of systems' integrated with the MER GDS. Overviews of the interconnected product generating systems will also be provided with emphasis on interdependencies, including those for a) geometric rectificationn of camera lens distortions, b) generation of stereo disparity, c) derivation of 3-dimensional coordinates in XYZ space, d) generation of unified terrain meshes, e) camera-to-target ranging (distance) and f) multi-image mosaicking.
Coincidence ion imaging with a fast frame camera
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Suk Kyoung; Cudry, Fadia; Lin, Yun Fei
2014-12-15
A new time- and position-sensitive particle detection system based on a fast frame CMOS (complementary metal-oxide semiconductors) camera is developed for coincidence ion imaging. The system is composed of four major components: a conventional microchannel plate/phosphor screen ion imager, a fast frame CMOS camera, a single anode photomultiplier tube (PMT), and a high-speed digitizer. The system collects the positional information of ions from a fast frame camera through real-time centroiding while the arrival times are obtained from the timing signal of a PMT processed by a high-speed digitizer. Multi-hit capability is achieved by correlating the intensity of ion spots onmore » each camera frame with the peak heights on the corresponding time-of-flight spectrum of a PMT. Efficient computer algorithms are developed to process camera frames and digitizer traces in real-time at 1 kHz laser repetition rate. We demonstrate the capability of this system by detecting a momentum-matched co-fragments pair (methyl and iodine cations) produced from strong field dissociative double ionization of methyl iodide.« less
Line-Based Registration of Panoramic Images and LiDAR Point Clouds for Mobile Mapping.
Cui, Tingting; Ji, Shunping; Shan, Jie; Gong, Jianya; Liu, Kejian
2016-12-31
For multi-sensor integrated systems, such as the mobile mapping system (MMS), data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable.
Line-Based Registration of Panoramic Images and LiDAR Point Clouds for Mobile Mapping
Cui, Tingting; Ji, Shunping; Shan, Jie; Gong, Jianya; Liu, Kejian
2016-01-01
For multi-sensor integrated systems, such as the mobile mapping system (MMS), data fusion at sensor-level, i.e., the 2D-3D registration between an optical camera and LiDAR, is a prerequisite for higher level fusion and further applications. This paper proposes a line-based registration method for panoramic images and a LiDAR point cloud collected by a MMS. We first introduce the system configuration and specification, including the coordinate systems of the MMS, the 3D LiDAR scanners, and the two panoramic camera models. We then establish the line-based transformation model for the panoramic camera. Finally, the proposed registration method is evaluated for two types of camera models by visual inspection and quantitative comparison. The results demonstrate that the line-based registration method can significantly improve the alignment of the panoramic image and the LiDAR datasets under either the ideal spherical or the rigorous panoramic camera model, with the latter being more reliable. PMID:28042855
Implementation of a Multi-Robot Coverage Algorithm on a Two-Dimensional, Grid-Based Environment
2017-06-01
two planar laser range finders with a 180-degree field of view , color camera, vision beacons, and wireless communicator. In their system, the robots...Master’s thesis 4. TITLE AND SUBTITLE IMPLEMENTATION OF A MULTI -ROBOT COVERAGE ALGORITHM ON A TWO -DIMENSIONAL, GRID-BASED ENVIRONMENT 5. FUNDING NUMBERS...path planning coverage algorithm for a multi -robot system in a two -dimensional, grid-based environment. We assess the applicability of a topology
A Bevel Gear Quality Inspection System Based on Multi-Camera Vision Technology.
Liu, Ruiling; Zhong, Dexing; Lyu, Hongqiang; Han, Jiuqiang
2016-08-25
Surface defect detection and dimension measurement of automotive bevel gears by manual inspection are costly, inefficient, low speed and low accuracy. In order to solve these problems, a synthetic bevel gear quality inspection system based on multi-camera vision technology is developed. The system can detect surface defects and measure gear dimensions simultaneously. Three efficient algorithms named Neighborhood Average Difference (NAD), Circle Approximation Method (CAM) and Fast Rotation-Position (FRP) are proposed. The system can detect knock damage, cracks, scratches, dents, gibbosity or repeated cutting of the spline, etc. The smallest detectable defect is 0.4 mm × 0.4 mm and the precision of dimension measurement is about 40-50 μm. One inspection process takes no more than 1.3 s. Both precision and speed meet the requirements of real-time online inspection in bevel gear production.
A novel camera localization system for extending three-dimensional digital image correlation
NASA Astrophysics Data System (ADS)
Sabato, Alessandro; Reddy, Narasimha; Khan, Sameer; Niezrecki, Christopher
2018-03-01
The monitoring of civil, mechanical, and aerospace structures is important especially as these systems approach or surpass their design life. Often, Structural Health Monitoring (SHM) relies on sensing techniques for condition assessment. Advancements achieved in camera technology and optical sensors have made three-dimensional (3D) Digital Image Correlation (DIC) a valid technique for extracting structural deformations and geometry profiles. Prior to making stereophotogrammetry measurements, a calibration has to be performed to obtain the vision systems' extrinsic and intrinsic parameters. It means that the position of the cameras relative to each other (i.e. separation distance, cameras angle, etc.) must be determined. Typically, cameras are placed on a rigid bar to prevent any relative motion between the cameras. This constraint limits the utility of the 3D-DIC technique, especially as it is applied to monitor large-sized structures and from various fields of view. In this preliminary study, the design of a multi-sensor system is proposed to extend 3D-DIC's capability and allow for easier calibration and measurement. The suggested system relies on a MEMS-based Inertial Measurement Unit (IMU) and a 77 GHz radar sensor for measuring the orientation and relative distance of the stereo cameras. The feasibility of the proposed combined IMU-radar system is evaluated through laboratory tests, demonstrating its ability in determining the cameras position in space for performing accurate 3D-DIC calibration and measurements.
Design and Development of a Low-Cost Aerial Mobile Mapping System for Multi-Purpose Applications
NASA Astrophysics Data System (ADS)
Acevedo Pardo, C.; Farjas Abadía, M.; Sternberg, H.
2015-08-01
The research project with the working title "Design and development of a low-cost modular Aerial Mobile Mapping System" was formed during the last year as the result from numerous discussions and considerations with colleagues from the HafenCity University Hamburg, Department Geomatics. The aim of the project is to design a sensor platform which can be embedded preferentially on an UAV, but also can be integrated on any adaptable vehicle. The system should perform a direct scanning of surfaces with a laser scanner and supported through sensors for determining the position and attitude of the platform. The modular design allows his extension with other sensors such as multispectral cameras, digital cameras or multiple cameras systems.
High-immersion three-dimensional display of the numerical computer model
NASA Astrophysics Data System (ADS)
Xing, Shujun; Yu, Xunbo; Zhao, Tianqi; Cai, Yuanfa; Chen, Duo; Chen, Zhidong; Sang, Xinzhu
2013-08-01
High-immersion three-dimensional (3D) displays making them valuable tools for many applications, such as designing and constructing desired building houses, industrial architecture design, aeronautics, scientific research, entertainment, media advertisement, military areas and so on. However, most technologies provide 3D display in the front of screens which are in parallel with the walls, and the sense of immersion is decreased. To get the right multi-view stereo ground image, cameras' photosensitive surface should be parallax to the public focus plane and the cameras' optical axes should be offset to the center of public focus plane both atvertical direction and horizontal direction. It is very common to use virtual cameras, which is an ideal pinhole camera to display 3D model in computer system. We can use virtual cameras to simulate the shooting method of multi-view ground based stereo image. Here, two virtual shooting methods for ground based high-immersion 3D display are presented. The position of virtual camera is determined by the people's eye position in the real world. When the observer stand in the circumcircle of 3D ground display, offset perspective projection virtual cameras is used. If the observer stands out the circumcircle of 3D ground display, offset perspective projection virtual cameras and the orthogonal projection virtual cameras are adopted. In this paper, we mainly discussed the parameter setting of virtual cameras. The Near Clip Plane parameter setting is the main point in the first method, while the rotation angle of virtual cameras is the main point in the second method. In order to validate the results, we use the D3D and OpenGL to render scenes of different viewpoints and generate a stereoscopic image. A realistic visualization system for 3D models is constructed and demonstrated for viewing horizontally, which provides high-immersion 3D visualization. The displayed 3D scenes are compared with the real objects in the real world.
The Beagle 2 Stereo Camera System: Scientific Objectives and Design Characteristics
NASA Astrophysics Data System (ADS)
Griffiths, A.; Coates, A.; Josset, J.; Paar, G.; Sims, M.
2003-04-01
The Stereo Camera System (SCS) will provide wide-angle (48 degree) multi-spectral stereo imaging of the Beagle 2 landing site in Isidis Planitia with an angular resolution of 0.75 milliradians. Based on the SpaceX Modular Micro-Imager, the SCS is composed of twin cameras (with 1024 by 1024 pixel frame transfer CCD) and twin filter wheel units (with a combined total of 24 filters). The primary mission objective is to construct a digital elevation model of the area in reach of the lander’s robot arm. The SCS specifications and following baseline studies are described: Panoramic RGB colour imaging of the landing site and panoramic multi-spectral imaging at 12 distinct wavelengths to study the mineralogy of landing site. Solar observations to measure water vapour absorption and the atmospheric dust optical density. Also envisaged are multi-spectral observations of Phobos &Deimos (observations of the moons relative to background stars will be used to determine the lander’s location and orientation relative to the Martian surface), monitoring of the landing site to detect temporal changes, observation of the actions and effects of the other PAW experiments (including rock texture studies with a close-up-lens) and collaborative observations with the Mars Express orbiter instrument teams. Due to be launched in May of this year, the total system mass is 360 g, the required volume envelope is 747 cm^3 and the average power consumption is 1.8 W. A 10Mbit/s RS422 bus connects each camera to the lander common electronics.
Traffic Sign Recognition with Invariance to Lighting in Dual-Focal Active Camera System
NASA Astrophysics Data System (ADS)
Gu, Yanlei; Panahpour Tehrani, Mehrdad; Yendo, Tomohiro; Fujii, Toshiaki; Tanimoto, Masayuki
In this paper, we present an automatic vision-based traffic sign recognition system, which can detect and classify traffic signs at long distance under different lighting conditions. To realize this purpose, the traffic sign recognition is developed in an originally proposed dual-focal active camera system. In this system, a telephoto camera is equipped as an assistant of a wide angle camera. The telephoto camera can capture a high accuracy image for an object of interest in the view field of the wide angle camera. The image from the telephoto camera provides enough information for recognition when the accuracy of traffic sign is low from the wide angle camera. In the proposed system, the traffic sign detection and classification are processed separately for different images from the wide angle camera and telephoto camera. Besides, in order to detect traffic sign from complex background in different lighting conditions, we propose a type of color transformation which is invariant to light changing. This color transformation is conducted to highlight the pattern of traffic signs by reducing the complexity of background. Based on the color transformation, a multi-resolution detector with cascade mode is trained and used to locate traffic signs at low resolution in the image from the wide angle camera. After detection, the system actively captures a high accuracy image of each detected traffic sign by controlling the direction and exposure time of the telephoto camera based on the information from the wide angle camera. Moreover, in classification, a hierarchical classifier is constructed and used to recognize the detected traffic signs in the high accuracy image from the telephoto camera. Finally, based on the proposed system, a set of experiments in the domain of traffic sign recognition is presented. The experimental results demonstrate that the proposed system can effectively recognize traffic signs at low resolution in different lighting conditions.
A Design and Development of Multi-Purpose CCD Camera System with Thermoelectric Cooling: Software
NASA Astrophysics Data System (ADS)
Oh, S. H.; Kang, Y. W.; Byun, Y. I.
2007-12-01
We present a software which we developed for the multi-purpose CCD camera. This software can be used on the all 3 types of CCD - KAF-0401E (768×512), KAF-1602E (15367times;1024), KAF-3200E (2184×1472) made in KODAK Co.. For the efficient CCD camera control, the software is operated with two independent processes of the CCD control program and the temperature/shutter operation program. This software is designed to fully automatic operation as well as manually operation under LINUX system, and is controled by LINUX user signal procedure. We plan to use this software for all sky survey system and also night sky monitoring and sky observation. As our results, the read-out time of each CCD are about 15sec, 64sec, 134sec for KAF-0401E, KAF-1602E, KAF-3200E., because these time are limited by the data transmission speed of parallel port. For larger format CCD, the data transmission is required more high speed. we are considering this control software to one using USB port for high speed data transmission.
A multi-camera system for real-time pose estimation
NASA Astrophysics Data System (ADS)
Savakis, Andreas; Erhard, Matthew; Schimmel, James; Hnatow, Justin
2007-04-01
This paper presents a multi-camera system that performs face detection and pose estimation in real-time and may be used for intelligent computing within a visual sensor network for surveillance or human-computer interaction. The system consists of a Scene View Camera (SVC), which operates at a fixed zoom level, and an Object View Camera (OVC), which continuously adjusts its zoom level to match objects of interest. The SVC is set to survey the whole filed of view. Once a region has been identified by the SVC as a potential object of interest, e.g. a face, the OVC zooms in to locate specific features. In this system, face candidate regions are selected based on skin color and face detection is accomplished using a Support Vector Machine classifier. The locations of the eyes and mouth are detected inside the face region using neural network feature detectors. Pose estimation is performed based on a geometrical model, where the head is modeled as a spherical object that rotates upon the vertical axis. The triangle formed by the mouth and eyes defines a vertical plane that intersects the head sphere. By projecting the eyes-mouth triangle onto a two dimensional viewing plane, equations were obtained that describe the change in its angles as the yaw pose angle increases. These equations are then combined and used for efficient pose estimation. The system achieves real-time performance for live video input. Testing results assessing system performance are presented for both still images and video.
Multi-channel automotive night vision system
NASA Astrophysics Data System (ADS)
Lu, Gang; Wang, Li-jun; Zhang, Yi
2013-09-01
A four-channel automotive night vision system is designed and developed .It is consist of the four active near-infrared cameras and an Mulit-channel image processing display unit,cameras were placed in the automobile front, left, right and rear of the system .The system uses near-infrared laser light source,the laser light beam is collimated, the light source contains a thermoelectric cooler (TEC),It can be synchronized with the camera focusing, also has an automatic light intensity adjustment, and thus can ensure the image quality. The principle of composition of the system is description in detail,on this basis, beam collimation,the LD driving and LD temperature control of near-infrared laser light source,four-channel image processing display are discussed.The system can be used in driver assistance, car BLIS, car parking assist system and car alarm system in day and night.
Coincidence electron/ion imaging with a fast frame camera
NASA Astrophysics Data System (ADS)
Li, Wen; Lee, Suk Kyoung; Lin, Yun Fei; Lingenfelter, Steven; Winney, Alexander; Fan, Lin
2015-05-01
A new time- and position- sensitive particle detection system based on a fast frame CMOS camera is developed for coincidence electron/ion imaging. The system is composed of three major components: a conventional microchannel plate (MCP)/phosphor screen electron/ion imager, a fast frame CMOS camera and a high-speed digitizer. The system collects the positional information of ions/electrons from a fast frame camera through real-time centroiding while the arrival times are obtained from the timing signal of MCPs processed by a high-speed digitizer. Multi-hit capability is achieved by correlating the intensity of electron/ion spots on each camera frame with the peak heights on the corresponding time-of-flight spectrum. Efficient computer algorithms are developed to process camera frames and digitizer traces in real-time at 1 kHz laser repetition rate. We demonstrate the capability of this system by detecting a momentum-matched co-fragments pair (methyl and iodine cations) produced from strong field dissociative double ionization of methyl iodide. We further show that a time resolution of 30 ps can be achieved when measuring electron TOF spectrum and this enables the new system to achieve a good energy resolution along the TOF axis.
A Bevel Gear Quality Inspection System Based on Multi-Camera Vision Technology
Liu, Ruiling; Zhong, Dexing; Lyu, Hongqiang; Han, Jiuqiang
2016-01-01
Surface defect detection and dimension measurement of automotive bevel gears by manual inspection are costly, inefficient, low speed and low accuracy. In order to solve these problems, a synthetic bevel gear quality inspection system based on multi-camera vision technology is developed. The system can detect surface defects and measure gear dimensions simultaneously. Three efficient algorithms named Neighborhood Average Difference (NAD), Circle Approximation Method (CAM) and Fast Rotation-Position (FRP) are proposed. The system can detect knock damage, cracks, scratches, dents, gibbosity or repeated cutting of the spline, etc. The smallest detectable defect is 0.4 mm × 0.4 mm and the precision of dimension measurement is about 40–50 μm. One inspection process takes no more than 1.3 s. Both precision and speed meet the requirements of real-time online inspection in bevel gear production. PMID:27571078
Multi-camera digital image correlation method with distributed fields of view
NASA Astrophysics Data System (ADS)
Malowany, Krzysztof; Malesa, Marcin; Kowaluk, Tomasz; Kujawinska, Malgorzata
2017-11-01
A multi-camera digital image correlation (DIC) method and system for measurements of large engineering objects with distributed, non-overlapping areas of interest are described. The data obtained with individual 3D DIC systems are stitched by an algorithm which utilizes the positions of fiducial markers determined simultaneously by Stereo-DIC units and laser tracker. The proposed calibration method enables reliable determination of transformations between local (3D DIC) and global coordinate systems. The applicability of the method was proven during in-situ measurements of a hall made of arch-shaped (18 m span) self-supporting metal-plates. The proposed method is highly recommended for 3D measurements of shape and displacements of large and complex engineering objects made from multiple directions and it provides the suitable accuracy of data for further advanced structural integrity analysis of such objects.
A modular positron camera for the study of industrial processes
NASA Astrophysics Data System (ADS)
Leadbeater, T. W.; Parker, D. J.
2011-10-01
Positron imaging techniques rely on the detection of the back-to-back annihilation photons arising from positron decay within the system under study. A standard technique, called positron emitting particle tracking (PEPT) [1], uses a number of these detected events to rapidly determine the position of a positron emitting tracer particle introduced into the system under study. Typical applications of PEPT are in the study of granular and multi-phase materials in the disciplines of engineering and the physical sciences. Using components from redundant medical PET scanners a modular positron camera has been developed. This camera consists of a number of small independent detector modules, which can be arranged in custom geometries tailored towards the application in question. The flexibility of the modular camera geometry allows for high photon detection efficiency within specific regions of interest, the ability to study large and bulky systems and the application of PEPT to difficult or remote processes as the camera is inherently transportable.
Time-lapse photogrammetry in geomorphic studies
NASA Astrophysics Data System (ADS)
Eltner, Anette; Kaiser, Andreas
2017-04-01
Image based approaches to reconstruct the earth surface (Structure from Motion - SfM) are establishing as a standard technology for high resolution topographic data. This is amongst other advantages due to the comparatively ease of use and flexibility of data generation. Furthermore, the increased spatial resolution led to its implementation at a vast range of applications from sub-mm to tens-of-km scale. Almost fully automatic calculation of referenced digital elevation models allows for a significant increase of temporal resolution, as well, potentially up to sub-second scales. Thereby, the setup of a time-lapse multi-camera system is necessary and different aspects need to be considered: The camera array has to be temporary stable or potential movements need to be compensated by temporary stable reference targets/areas. The stability of the internal camera geometry has to be considered due to a usually significantly lower amount of images of the scene, and thus redundancy for parameter estimation, compared to more common SfM applications. Depending on the speed of surface change, synchronisation has to be very accurate. Due to the usual application in the field, changing environmental conditions important for lighting and visual range are also crucial factors to keep in mind. Besides these important considerations much potential is comprised by time-lapse photogrammetry. The integration of multi-sensor systems, e.g. using thermal cameras, enables the potential detection of other processes not visible with RGB-images solely. Furthermore, the implementation of low-cost sensors allows for a significant increase of areal coverage and their setup at locations, where a loss of the system cannot be ruled out. The usage of micro-computers offers smart camera triggering, e.g. acquiring images with increased frequency controlled by a rainfall-triggered sensor. In addition these micro-computers can enable on-site data processing, e.g. recognition of increased surface movement, and thus might be used as warning system in the case of natural hazards. A large variety of applications are suitable with time-lapse photogrammetry, i.e. change detection of all sorts; e.g. volumetric alterations, movement tracking or roughness changes. The multi-camera systems can be used for slope investigations, soil studies, glacier observation, snow cover measurement, volcanic surveillance or plant growth monitoring. A conceptual workflow is introduced highlighting the limits and potentials of time-lapse photogrammetry.
HIGH SPEED KERR CELL FRAMING CAMERA
Goss, W.C.; Gilley, L.F.
1964-01-01
The present invention relates to a high speed camera utilizing a Kerr cell shutter and a novel optical delay system having no moving parts. The camera can selectively photograph at least 6 frames within 9 x 10/sup -8/ seconds during any such time interval of an occurring event. The invention utilizes particularly an optical system which views and transmits 6 images of an event to a multi-channeled optical delay relay system. The delay relay system has optical paths of successively increased length in whole multiples of the first channel optical path length, into which optical paths the 6 images are transmitted. The successively delayed images are accepted from the exit of the delay relay system by an optical image focusing means, which in turn directs the images into a Kerr cell shutter disposed to intercept the image paths. A camera is disposed to simultaneously view and record the 6 images during a single exposure of the Kerr cell shutter. (AEC)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rilling, M; Centre de Recherche sur le Cancer, Hôtel-Dieu de Québec, Quebec City, QC; Département de radio-oncologie, CHU de Québec, Quebec City, QC
2015-06-15
Purpose: The purpose of this work is to simulate a multi-focus plenoptic camera used as the measuring device in a real-time three-dimensional scintillation dosimeter. Simulating and optimizing this realistic optical system will bridge the technological gap between concept validation and a clinically viable tool that can provide highly efficient, accurate and precise measurements for dynamic radiotherapy techniques. Methods: The experimental prototype, previously developed for proof of concept purposes, uses an off-the-shelf multi-focus plenoptic camera. With an array of interleaved microlenses of different focal lengths, this camera records spatial and angular information of light emitted by a plastic scintillator volume. Themore » three distinct microlens focal lengths were determined experimentally for use as baseline parameters by measuring image-to-object magnification for different distances in object space. A simulated plenoptic system was implemented using the non-sequential ray tracing software Zemax: this tool allows complete simulation of multiple optical paths by modeling interactions at interfaces such as scatter, diffraction, reflection and refraction. The active sensor was modeled based on the camera manufacturer specifications by a 2048×2048, 5 µm-pixel pitch sensor. Planar light sources, simulating the plastic scintillator volume, were employed for ray tracing simulations. Results: The microlens focal lengths were determined to be 384, 327 and 290 µm. A realistic multi-focus plenoptic system, with independently defined and optimizable specifications, was fully simulated. A f/2.9 and 54 mm-focal length Double Gauss objective was modeled as the system’s main lens. A three-focal length hexagonal microlens array of 250-µm thickness was designed, acting as an image-relay system between the main lens and sensor. Conclusion: Simulation of a fully modeled multi-focus plenoptic camera enables the decoupled optimization of the main lens and microlens specifications. This work leads the way to improving the 3D dosimeter’s achievable resolution, efficiency and build for providing a quality assurance tool fully meeting clinical needs. M.R. is financially supported by a Master’s Canada Graduate Scholarship from the NSERC. This research is also supported by the NSERC Industrial Research Chair in Optical Design.« less
Proper Orthogonal Decomposition on Experimental Multi-phase Flow in a Pipe
NASA Astrophysics Data System (ADS)
Viggiano, Bianca; Tutkun, Murat; Cal, Raúl Bayoán
2016-11-01
Multi-phase flow in a 10 cm diameter pipe is analyzed using proper orthogonal decomposition. The data were obtained using X-ray computed tomography in the Well Flow Loop at the Institute for Energy Technology in Kjeller, Norway. The system consists of two sources and two detectors; one camera records the vertical beams and one camera records the horizontal beams. The X-ray system allows measurement of phase holdup, cross-sectional phase distributions and gas-liquid interface characteristics within the pipe. The mathematical framework in the context of multi-phase flows is developed. Phase fractions of a two-phase (gas-liquid) flow are analyzed and a reduced order description of the flow is generated. Experimental data deepens the complexity of the analysis with limited known quantities for reconstruction. Comparison between the reconstructed fields and the full data set allows observation of the important features. The mathematical description obtained from the decomposition will deepen the understanding of multi-phase flow characteristics and is applicable to fluidized beds, hydroelectric power and nuclear processes to name a few.
A higher-speed compressive sensing camera through multi-diode design
NASA Astrophysics Data System (ADS)
Herman, Matthew A.; Tidman, James; Hewitt, Donna; Weston, Tyler; McMackin, Lenore
2013-05-01
Obtaining high frame rates is a challenge with compressive sensing (CS) systems that gather measurements in a sequential manner, such as the single-pixel CS camera. One strategy for increasing the frame rate is to divide the FOV into smaller areas that are sampled and reconstructed in parallel. Following this strategy, InView has developed a multi-aperture CS camera using an 8×4 array of photodiodes that essentially act as 32 individual simultaneously operating single-pixel cameras. Images reconstructed from each of the photodiode measurements are stitched together to form the full FOV. To account for crosstalk between the sub-apertures, novel modulation patterns have been developed to allow neighboring sub-apertures to share energy. Regions of overlap not only account for crosstalk energy that would otherwise be reconstructed as noise, but they also allow for tolerance in the alignment of the DMD to the lenslet array. Currently, the multi-aperture camera is built into a computational imaging workstation configuration useful for research and development purposes. In this configuration, modulation patterns are generated in a CPU and sent to the DMD via PCI express, which allows the operator to develop and change the patterns used in the data acquisition step. The sensor data is collected and then streamed to the workstation via an Ethernet or USB connection for the reconstruction step. Depending on the amount of data taken and the amount of overlap between sub-apertures, frame rates of 2-5 frames per second can be achieved. In a stand-alone camera platform, currently in development, pattern generation and reconstruction will be implemented on-board.
Development of two-framing camera with large format and ultrahigh speed
NASA Astrophysics Data System (ADS)
Jiang, Xiaoguo; Wang, Yuan; Wang, Yi
2012-10-01
High-speed imaging facility is important and necessary for the formation of time-resolved measurement system with multi-framing capability. The framing camera which satisfies the demands of both high speed and large format needs to be specially developed in the ultrahigh speed research field. A two-framing camera system with high sensitivity and time-resolution has been developed and used for the diagnosis of electron beam parameters of Dragon-I linear induction accelerator (LIA). The camera system, which adopts the principle of light beam splitting in the image space behind the lens with long focus length, mainly consists of lens-coupled gated image intensifier, CCD camera and high-speed shutter trigger device based on the programmable integrated circuit. The fastest gating time is about 3 ns, and the interval time between the two frames can be adjusted discretely at the step of 0.5 ns. Both the gating time and the interval time can be tuned to the maximum value of about 1 s independently. Two images with the size of 1024×1024 for each can be captured simultaneously in our developed camera. Besides, this camera system possesses a good linearity, uniform spatial response and an equivalent background illumination as low as 5 electrons/pix/sec, which fully meets the measurement requirements of Dragon-I LIA.
Design of tangential multi-energy SXR cameras for tokamak plasmas
NASA Astrophysics Data System (ADS)
Yamazaki, H.; Delgado-Aparicio, L. F.; Pablant, N.; Hill, K.; Bitter, M.; Takase, Y.; Ono, M.; Stratton, B.
2017-10-01
A new synthetic diagnostic capability has been built to study the response of tangential multi-energy soft x-ray pin-hole cameras for arbitrary plasma densities (ne , D), temperature (Te) and ion concentrations (nZ). For tokamaks and future facilities to operate safely in a high-pressure long-pulse discharge, it is imperative to address key issues associated with impurity sources, core transport and high-Z impurity accumulation. Multi-energy soft xray imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (e.g. Te, nZ and ΔZeff). These systems are designed to sample the continuum- and line-emission from low- to high-Z impurities (e.g. C, O, Al, Si, Ar, Ca, Fe, Ni and Mo) in multiple energy-ranges. These x-ray cameras will be installed in the MST-RFP, as well as NSTX-U and DIII-D tokamaks, measuring the radial structure of the photon emissivity with a radial resolution below 1 cm at a 500 Hz frame rate and a photon-energy resolution of 500 eV. The layout and response expected for the new systems will be shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation is also addressed for the case of NSTX-U.
Konduru, Anil Reddy; Yelikar, Balasaheb R; Sathyashree, K V; Kumar, Ankur
2018-01-01
Open source technologies and mobile innovations have radically changed the way people interact with technology. These innovations and advancements have been used across various disciplines and already have a significant impact. Microscopy, with focus on visually appealing contrasting colors for better appreciation of morphology, forms the core of the disciplines such as Pathology, microbiology, and anatomy. Here, learning happens with the aid of multi-head microscopes and digital camera systems for teaching larger groups and in organizing interactive sessions for students or faculty of other departments. The cost of the original equipment manufacturer (OEM) camera systems in bringing this useful technology at all the locations is a limiting factor. To avoid this, we have used the low-cost technologies like Raspberry Pi, Mobile high definition link and 3D printing for adapters to create portable camera systems. Adopting these open source technologies enabled us to convert any binocular or trinocular microscope be connected to a projector or HD television at a fraction of the cost of the OEM camera systems with comparable quality. These systems, in addition to being cost-effective, have also provided the added advantage of portability, thus providing the much-needed flexibility at various teaching locations.
NASA Astrophysics Data System (ADS)
Chetty, S.; Field, L. A.
2013-12-01
The Arctic ocean's continuing decrease of summer-time ice is related to rapidly diminishing multi-year ice due to the effects of climate change. Ice911 Research aims to develop environmentally respectful materials that when deployed will increase the albedo, enhancing the formation and/preservation of multi-year ice. Small scale deployments using various materials have been done in Canada, California's Sierra Nevada Mountains and a pond in Minnesota to test the albedo performance and environmental characteristics of these materials. SWIMS is a sophisticated autonomous sensor system being developed to measure the albedo, weather, water temperature and other environmental parameters. The system (SWIMS) employs low cost, high accuracy/precision sensors, high resolution cameras, and an extreme environment command and data handling computer system using satellite and terrestrial wireless communication. The entire system is solar powered with redundant battery backup on a floating buoy platform engineered for low temperature (-40C) and high wind conditions. The system also incorporates tilt sensors, sonar based ice thickness sensors and a weather station. To keep the costs low, each SWIMS unit measures incoming and reflected radiation from the four quadrants around the buoy. This allows data from four sets of sensors, cameras, weather station, water temperature probe to be collected and transmitted by a single on-board solar powered computer. This presentation covers the technical, logistical and cost challenges in designing, developing and deploying these stations in remote, extreme environments. Image captured by camera #3 of setting sun on the SWIMS station One of the images captured by SWIMS Camera #4
Application of infrared uncooled cameras in surveillance systems
NASA Astrophysics Data System (ADS)
Dulski, R.; Bareła, J.; Trzaskawka, P.; PiÄ tkowski, T.
2013-10-01
The recent necessity to protect military bases, convoys and patrols gave serious impact to the development of multisensor security systems for perimeter protection. One of the most important devices used in such systems are IR cameras. The paper discusses technical possibilities and limitations to use uncooled IR camera in a multi-sensor surveillance system for perimeter protection. Effective ranges of detection depend on the class of the sensor used and the observed scene itself. Application of IR camera increases the probability of intruder detection regardless of the time of day or weather conditions. It also simultaneously decreased the false alarm rate produced by the surveillance system. The role of IR cameras in the system was discussed as well as technical possibilities to detect human being. Comparison of commercially available IR cameras, capable to achieve desired ranges was done. The required spatial resolution for detection, recognition and identification was calculated. The simulation of detection ranges was done using a new model for predicting target acquisition performance which uses the Targeting Task Performance (TTP) metric. Like its predecessor, the Johnson criteria, the new model bounds the range performance with image quality. The scope of presented analysis is limited to the estimation of detection, recognition and identification ranges for typical thermal cameras with uncooled microbolometer focal plane arrays. This type of cameras is most widely used in security systems because of competitive price to performance ratio. Detection, recognition and identification range calculations were made, and the appropriate results for the devices with selected technical specifications were compared and discussed.
NASA Astrophysics Data System (ADS)
Stavroulakis, Petros I.; Chen, Shuxiao; Sims-Waterhouse, Danny; Piano, Samanta; Southon, Nicholas; Bointon, Patrick; Leach, Richard
2017-06-01
In non-rigid fringe projection 3D measurement systems, where either the camera or projector setup can change significantly between measurements or the object needs to be tracked, self-calibration has to be carried out frequently to keep the measurements accurate1. In fringe projection systems, it is common to use methods developed initially for photogrammetry for the calibration of the camera(s) in the system in terms of extrinsic and intrinsic parameters. To calibrate the projector(s) an extra correspondence between a pre-calibrated camera and an image created by the projector is performed. These recalibration steps are usually time consuming and involve the measurement of calibrated patterns on planes, before the actual object can continue to be measured after a motion of a camera or projector has been introduced in the setup and hence do not facilitate fast 3D measurement of objects when frequent experimental setup changes are necessary. By employing and combining a priori information via inverse rendering, on-board sensors, deep learning and leveraging a graphics processor unit (GPU), we assess a fine camera pose estimation method which is based on optimising the rendering of a model of a scene and the object to match the view from the camera. We find that the success of this calibration pipeline can be greatly improved by using adequate a priori information from the aforementioned sources.
NASA Astrophysics Data System (ADS)
Zalameda, Joseph N.; Burke, Eric R.; Hafley, Robert A.; Taminger, Karen M.; Domack, Christopher S.; Brewer, Amy; Martin, Richard E.
2013-05-01
Additive manufacturing is a rapidly growing field where 3-dimensional parts can be produced layer by layer. NASA's electron beam freeform fabrication (EBF3) technology is being evaluated to manufacture metallic parts in a space environment. The benefits of EBF3 technology are weight savings to support space missions, rapid prototyping in a zero gravity environment, and improved vehicle readiness. The EBF3 system is composed of 3 main components: electron beam gun, multi-axis position system, and metallic wire feeder. The electron beam is used to melt the wire and the multi-axis positioning system is used to build the part layer by layer. To insure a quality deposit, a near infrared (NIR) camera is used to image the melt pool and solidification areas. This paper describes the calibration and application of a NIR camera for temperature measurement. In addition, image processing techniques are presented for deposit assessment metrics.
Virtual viewpoint synthesis in multi-view video system
NASA Astrophysics Data System (ADS)
Li, Fang; Yang, Shiqiang
2005-07-01
In this paper, we present a virtual viewpoint video synthesis algorithm to satisfy the following three aims: low computing consuming; real time interpolation and acceptable video quality. In contrast with previous technologies, this method obtain incompletely 3D structure using neighbor video sources instead of getting total 3D information with all video sources, so that the computation is reduced greatly. So we demonstrate our interactive multi-view video synthesis algorithm in a personal computer. Furthermore, adopting the method of choosing feature points to build the correspondence between the frames captured by neighbor cameras, we need not require camera calibration. Finally, our method can be used when the angle between neighbor cameras is 25-30 degrees that it is much larger than common computer vision experiments. In this way, our method can be applied into many applications such as sports live, video conference, etc.
NASA Technical Reports Server (NTRS)
1993-01-01
Johnson Space Flight Center's device to test astronauts' heart function in microgravity has led to the MultiWire Gamma Camera, which images heart conditions six times faster than conventional devices. Dr. Jeffrey Lacy, who developed the technology as a NASA researcher, later formed Proportional Technologies, Inc. to develop a commercially viable process that would enable use of Tantalum-178 (Ta-178), a radio-pharmaceutical. His company supplies the generator for the radioactive Ta-178 to Xenos Medical Systems, which markets the camera. Ta-178 can only be optimally imaged with the camera. Because the body is subjected to it for only nine minutes, the radiation dose is significantly reduced and the technique can be used more frequently. Ta-178 also enables the camera to be used on pediatric patients who are rarely studied with conventional isotopes because of the high radiation dosage.
Zhan, Dong; Yu, Long; Xiao, Jian; Chen, Tanglong
2015-04-14
Railway tunnel 3D clearance inspection is critical to guaranteeing railway operation safety. However, it is a challenge to inspect railway tunnel 3D clearance using a vision system, because both the spatial range and field of view (FOV) of such measurements are quite large. This paper summarizes our work on dynamic railway tunnel 3D clearance inspection based on a multi-camera and structured-light vision system (MSVS). First, the configuration of the MSVS is described. Then, the global calibration for the MSVS is discussed in detail. The onboard vision system is mounted on a dedicated vehicle and is expected to suffer from multiple degrees of freedom vibrations brought about by the running vehicle. Any small vibration can result in substantial measurement errors. In order to overcome this problem, a vehicle motion deviation rectifying method is investigated. Experiments using the vision inspection system are conducted with satisfactory online measurement results.
Time-Of-Flight Camera, Optical Tracker and Computed Tomography in Pairwise Data Registration
Badura, Pawel; Juszczyk, Jan; Pietka, Ewa
2016-01-01
Purpose A growing number of medical applications, including minimal invasive surgery, depends on multi-modal or multi-sensors data processing. Fast and accurate 3D scene analysis, comprising data registration, seems to be crucial for the development of computer aided diagnosis and therapy. The advancement of surface tracking system based on optical trackers already plays an important role in surgical procedures planning. However, new modalities, like the time-of-flight (ToF) sensors, widely explored in non-medical fields are powerful and have the potential to become a part of computer aided surgery set-up. Connection of different acquisition systems promises to provide a valuable support for operating room procedures. Therefore, the detailed analysis of the accuracy of such multi-sensors positioning systems is needed. Methods We present the system combining pre-operative CT series with intra-operative ToF-sensor and optical tracker point clouds. The methodology contains: optical sensor set-up and the ToF-camera calibration procedures, data pre-processing algorithms, and registration technique. The data pre-processing yields a surface, in case of CT, and point clouds for ToF-sensor and marker-driven optical tracker representation of an object of interest. An applied registration technique is based on Iterative Closest Point algorithm. Results The experiments validate the registration of each pair of modalities/sensors involving phantoms of four various human organs in terms of Hausdorff distance and mean absolute distance metrics. The best surface alignment was obtained for CT and optical tracker combination, whereas the worst for experiments involving ToF-camera. Conclusion The obtained accuracies encourage to further develop the multi-sensors systems. The presented substantive discussion concerning the system limitations and possible improvements mainly related to the depth information produced by the ToF-sensor is useful for computer aided surgery developers. PMID:27434396
Distributed Compression in Camera Sensor Networks
2006-02-13
complicated in this context. This effort will make use of the correlation structure of the data given by the plenoptic function n the case of multi-camera...systems. In many cases the structure of the plenoptic function can be estimated without requiring inter-sensor communications, but by using some a...priori global geometrical information. Once the structure of the plenoptic function has been predicted, it is possible to develop specific distributed
Dynamic Geometry Capture with a Multi-View Structured-Light System
2014-12-19
funding was never a problem during my studies . One of the best parts of my time at UC Berkeley has been working with colleagues within the Video and...scientific and medical applications such as quantifying improvement in physical therapy and measuring unnatural poses in ergonomic studies . Specifically... cases with limited scene texture. This direct generation of surface geometry provides us with a distinct advantage over multi-camera based systems. For
Acquisition of gamma camera and physiological data by computer.
Hack, S N; Chang, M; Line, B R; Cooper, J A; Robeson, G H
1986-11-01
We have designed, implemented, and tested a new Research Data Acquisition System (RDAS) that permits a general purpose digital computer to acquire signals from both gamma camera sources and physiological signal sources concurrently. This system overcomes the limited multi-source, high speed data acquisition capabilities found in most clinically oriented nuclear medicine computers. The RDAS can simultaneously input signals from up to four gamma camera sources with a throughput of 200 kHz per source and from up to eight physiological signal sources with an aggregate throughput of 50 kHz. Rigorous testing has found the RDAS to exhibit acceptable linearity and timing characteristics. In addition, flood images obtained by this system were compared with flood images acquired by a commercial nuclear medicine computer system. National Electrical Manufacturers Association performance standards of the flood images were found to be comparable.
A new high-speed IR camera system
NASA Technical Reports Server (NTRS)
Travis, Jeffrey W.; Shu, Peter K.; Jhabvala, Murzy D.; Kasten, Michael S.; Moseley, Samuel H.; Casey, Sean C.; Mcgovern, Lawrence K.; Luers, Philip J.; Dabney, Philip W.; Kaipa, Ravi C.
1994-01-01
A multi-organizational team at the Goddard Space Flight Center is developing a new far infrared (FIR) camera system which furthers the state of the art for this type of instrument by the incorporating recent advances in several technological disciplines. All aspects of the camera system are optimized for operation at the high data rates required for astronomical observations in the far infrared. The instrument is built around a Blocked Impurity Band (BIB) detector array which exhibits responsivity over a broad wavelength band and which is capable of operating at 1000 frames/sec, and consists of a focal plane dewar, a compact camera head electronics package, and a Digital Signal Processor (DSP)-based data system residing in a standard 486 personal computer. In this paper we discuss the overall system architecture, the focal plane dewar, and advanced features and design considerations for the electronics. This system, or one derived from it, may prove useful for many commercial and/or industrial infrared imaging or spectroscopic applications, including thermal machine vision for robotic manufacturing, photographic observation of short-duration thermal events such as combustion or chemical reactions, and high-resolution surveillance imaging.
Object tracking using multiple camera video streams
NASA Astrophysics Data System (ADS)
Mehrubeoglu, Mehrube; Rojas, Diego; McLauchlan, Lifford
2010-05-01
Two synchronized cameras are utilized to obtain independent video streams to detect moving objects from two different viewing angles. The video frames are directly correlated in time. Moving objects in image frames from the two cameras are identified and tagged for tracking. One advantage of such a system involves overcoming effects of occlusions that could result in an object in partial or full view in one camera, when the same object is fully visible in another camera. Object registration is achieved by determining the location of common features in the moving object across simultaneous frames. Perspective differences are adjusted. Combining information from images from multiple cameras increases robustness of the tracking process. Motion tracking is achieved by determining anomalies caused by the objects' movement across frames in time in each and the combined video information. The path of each object is determined heuristically. Accuracy of detection is dependent on the speed of the object as well as variations in direction of motion. Fast cameras increase accuracy but limit the speed and complexity of the algorithm. Such an imaging system has applications in traffic analysis, surveillance and security, as well as object modeling from multi-view images. The system can easily be expanded by increasing the number of cameras such that there is an overlap between the scenes from at least two cameras in proximity. An object can then be tracked long distances or across multiple cameras continuously, applicable, for example, in wireless sensor networks for surveillance or navigation.
SFR test fixture for hemispherical and hyperhemispherical camera systems
NASA Astrophysics Data System (ADS)
Tamkin, John M.
2017-08-01
Optical testing of camera systems in volume production environments can often require expensive tooling and test fixturing. Wide field (fish-eye, hemispheric and hyperhemispheric) optical systems create unique challenges because of the inherent distortion, and difficulty in controlling reflections from front-lit high resolution test targets over the hemisphere. We present a unique design for a test fixture that uses low-cost manufacturing methods and equipment such as 3D printing and an Arduino processor to control back-lit multi-color (VIS/NIR) targets and sources. Special care with LED drive electronics is required to accommodate both global and rolling shutter sensors.
Optical Meteor Systems Used by the NASA Meteoroid Environment Office
NASA Technical Reports Server (NTRS)
Kingery, A. M.; Blaauw, R. C.; Cooke, W. J.; Moser, D. E.
2015-01-01
The NASA Meteoroid Environment Office (MEO) uses two main meteor camera networks to characterize the meteoroid environment: an all sky system and a wide field system to study cm and mm size meteors respectively. The NASA All Sky Fireball Network consists of fifteen meteor video cameras in the United States, with plans to expand to eighteen cameras by the end of 2015. The camera design and All-Sky Guided and Real-time Detection (ASGARD) meteor detection software [1, 2] were adopted from the University of Western Ontario's Southern Ontario Meteor Network (SOMN). After seven years of operation, the network has detected over 12,000 multi-station meteors, including meteors from at least 53 different meteor showers. The network is used for speed distribution determination, characterization of meteor showers and sporadic sources, and for informing the public on bright meteor events. The NASA Wide Field Meteor Network was established in December of 2012 with two cameras and expanded to eight cameras in December of 2014. The two camera configuration saw 5470 meteors over two years of operation with two cameras, and has detected 3423 meteors in the first five months of operation (Dec 12, 2014 - May 12, 2015) with eight cameras. We expect to see over 10,000 meteors per year with the expanded system. The cameras have a 20 degree field of view and an approximate limiting meteor magnitude of +5. The network's primary goal is determining the nightly shower and sporadic meteor fluxes. Both camera networks function almost fully autonomously with little human interaction required for upkeep and analysis. The cameras send their data to a central server for storage and automatic analysis. Every morning the servers automatically generates an e-mail and web page containing an analysis of the previous night's events. The current status of the networks will be described, alongside with preliminary results. In addition, future projects, CCD photometry and broadband meteor color camera system, will be discussed.
NASA Technical Reports Server (NTRS)
Gazanik, Michael; Johnson, Dave; Kist, Ed; Novak, Frank; Antill, Charles; Haakenson, David; Howell, Patricia; Jenkins, Rusty; Yates, Rusty; Stephan, Ryan;
2005-01-01
In November 2004, NASA's Space Shuttle Program approved the development of the Extravehicular (EVA) Infrared (IR) Camera to test the application of infrared thermography to on-orbit reinforced carbon-carbon (RCC) damage detection. A multi-center team composed of members from NASA's Johnson Space Center (JSC), Langley Research Center (LaRC), and Goddard Space Flight Center (GSFC) was formed to develop the camera system and plan a flight test. The initial development schedule called for the delivery of the system in time to support STS-115 in late 2005. At the request of Shuttle Program managers and the flight crews, the team accelerated its schedule and delivered a certified EVA IR Camera system in time to support STS-114 in July 2005 as a contingency. The development of the camera system, led by LaRC, was based on the Commercial-Off-the-Shelf (COTS) FLIR S65 handheld infrared camera. An assessment of the S65 system in regards to space-flight operation was critical to the project. This paper discusses the space-flight assessment and describes the significant modifications required for EVA use by the astronaut crew. The on-orbit inspection technique will be demonstrated during the third EVA of STS-121 in September 2005 by imaging damaged RCC samples mounted in a box in the Shuttle's cargo bay.
NASA Astrophysics Data System (ADS)
Chen, Chun-Jen; Wu, Wen-Hong; Huang, Kuo-Cheng
2009-08-01
A multi-function lens test instrument is report in this paper. This system can evaluate the image resolution, image quality, depth of field, image distortion and light intensity distribution of the tested lens by changing the tested patterns. This system consists of a tested lens, a CCD camera, a linear motorized stage, a system fixture, an observer LCD monitor, and a notebook for pattern providing. The LCD monitor displays a serious of specified tested patterns sent by the notebook. Then each displayed pattern goes through the tested lens and images in the CCD camera sensor. Consequently, the system can evaluate the performance of the tested lens by analyzing the image of CCD camera with special designed software. The major advantage of this system is that it can complete whole test quickly without interruption due to part replacement, because the tested patterns are statically displayed on monitor and controlled by the notebook.
Real-time vehicle matching for multi-camera tunnel surveillance
NASA Astrophysics Data System (ADS)
Jelača, Vedran; Niño Castañeda, Jorge Oswaldo; Frías-Velázquez, Andrés; Pižurica, Aleksandra; Philips, Wilfried
2011-03-01
Tracking multiple vehicles with multiple cameras is a challenging problem of great importance in tunnel surveillance. One of the main challenges is accurate vehicle matching across the cameras with non-overlapping fields of view. Since systems dedicated to this task can contain hundreds of cameras which observe dozens of vehicles each, for a real-time performance computational efficiency is essential. In this paper, we propose a low complexity, yet highly accurate method for vehicle matching using vehicle signatures composed of Radon transform like projection profiles of the vehicle image. The proposed signatures can be calculated by a simple scan-line algorithm, by the camera software itself and transmitted to the central server or to the other cameras in a smart camera environment. The amount of data is drastically reduced compared to the whole image, which relaxes the data link capacity requirements. Experiments on real vehicle images, extracted from video sequences recorded in a tunnel by two distant security cameras, validate our approach.
Recent advances in multiview distributed video coding
NASA Astrophysics Data System (ADS)
Dufaux, Frederic; Ouaret, Mourad; Ebrahimi, Touradj
2007-04-01
We consider dense networks of surveillance cameras capturing overlapped images of the same scene from different viewing directions, such a scenario being referred to as multi-view. Data compression is paramount in such a system due to the large amount of captured data. In this paper, we propose a Multi-view Distributed Video Coding approach. It allows for low complexity / low power consumption at the encoder side, and the exploitation of inter-view correlation without communications among the cameras. We introduce a combination of temporal intra-view side information and homography inter-view side information. Simulation results show both the improvement of the side information, as well as a significant gain in terms of coding efficiency.
Incremental Multi-view 3D Reconstruction Starting from Two Images Taken by a Stereo Pair of Cameras
NASA Astrophysics Data System (ADS)
El hazzat, Soulaiman; Saaidi, Abderrahim; Karam, Antoine; Satori, Khalid
2015-03-01
In this paper, we present a new method for multi-view 3D reconstruction based on the use of a binocular stereo vision system constituted of two unattached cameras to initialize the reconstruction process. Afterwards , the second camera of stereo vision system (characterized by varying parameters) moves to capture more images at different times which are used to obtain an almost complete 3D reconstruction. The first two projection matrices are estimated by using a 3D pattern with known properties. After that, 3D scene points are recovered by triangulation of the matched interest points between these two images. The proposed approach is incremental. At each insertion of a new image, the camera projection matrix is estimated using the 3D information already calculated and new 3D points are recovered by triangulation from the result of the matching of interest points between the inserted image and the previous image. For the refinement of the new projection matrix and the new 3D points, a local bundle adjustment is performed. At first, all projection matrices are estimated, the matches between consecutive images are detected and Euclidean sparse 3D reconstruction is obtained. So, to increase the number of matches and have a more dense reconstruction, the Match propagation algorithm, more suitable for interesting movement of the camera, was applied on the pairs of consecutive images. The experimental results show the power and robustness of the proposed approach.
Laser- and Multi-Spectral Monitoring of Natural Objects from UAVs
NASA Astrophysics Data System (ADS)
Reiterer, Alexander; Frey, Simon; Koch, Barbara; Stemmler, Simon; Weinacker, Holger; Hoffmann, Annemarie; Weiler, Markus; Hergarten, Stefan
2016-04-01
The paper describes the research, development and evaluation of a lightweight sensor system for UAVs. The system is composed of three main components: (1) a laser scanning module, (2) a multi-spectral camera system, and (3) a processing/storage unit. All three components are newly developed. Beside measurement precision and frequency, the low weight has been one of the challenging tasks. The current system has a total weight of about 2.5 kg and is designed as a self-contained unit (incl. storage and battery units). The main features of the system are: laser-based multi-echo 3D measurement by a wavelength of 905 nm (totally eye save), measurement range up to 200 m, measurement frequency of 40 kHz, scanning frequency of 16 Hz, relative distance accuracy of 10 mm. The system is equipped with both GNSS and IMU. Alternatively, a multi-visual-odometry system has been integrated to estimate the trajectory of the UAV by image features (based on this system a calculation of 3D-coordinates without GNSS is possible). The integrated multi-spectral camera system is based on conventional CMOS-image-chips equipped with a special sets of band-pass interference filters with a full width half maximum (FWHM) of 50 nm. Good results for calculating the normalized difference vegetation index (NDVI) and the wide dynamic range vegetation index (WDRVI) have been achieved using the band-pass interference filter-set with a FWHM of 50 nm and an exposure times between 5.000 μs and 7.000 μs. The system is currently used for monitoring of natural objects and surfaces, like forest, as well as for geo-risk analysis (landslides). By measuring 3D-geometric and multi-spectral information a reliable monitoring and interpretation of the data-set is possible. The paper gives an overview about the development steps, the system, the evaluation and first results.
A Novel Multi-Camera Calibration Method based on Flat Refractive Geometry
NASA Astrophysics Data System (ADS)
Huang, S.; Feng, M. C.; Zheng, T. X.; Li, F.; Wang, J. Q.; Xiao, L. F.
2018-03-01
Multi-camera calibration plays an important role in many field. In the paper, we present a novel multi-camera calibration method based on flat refractive geometry. All cameras can acquire calibration images of transparent glass calibration board (TGCB) at the same time. The application of TGCB leads to refractive phenomenon which can generate calibration error. The theory of flat refractive geometry is employed to eliminate the error. The new method can solve the refractive phenomenon of TGCB. Moreover, the bundle adjustment method is used to minimize the reprojection error and obtain optimized calibration results. Finally, the four-cameras calibration results of real data show that the mean value and standard deviation of the reprojection error of our method are 4.3411e-05 and 0.4553 pixel, respectively. The experimental results show that the proposed method is accurate and reliable.
Riza, Nabeel A; La Torre, Juan Pablo; Amin, M Junaid
2016-06-13
Proposed and experimentally demonstrated is the CAOS-CMOS camera design that combines the coded access optical sensor (CAOS) imager platform with the CMOS multi-pixel optical sensor. The unique CAOS-CMOS camera engages the classic CMOS sensor light staring mode with the time-frequency-space agile pixel CAOS imager mode within one programmable optical unit to realize a high dynamic range imager for extreme light contrast conditions. The experimentally demonstrated CAOS-CMOS camera is built using a digital micromirror device, a silicon point-photo-detector with a variable gain amplifier, and a silicon CMOS sensor with a maximum rated 51.3 dB dynamic range. White light imaging of three different brightness simultaneously viewed targets, that is not possible by the CMOS sensor, is achieved by the CAOS-CMOS camera demonstrating an 82.06 dB dynamic range. Applications for the camera include industrial machine vision, welding, laser analysis, automotive, night vision, surveillance and multispectral military systems.
Electro-optical system for gunshot detection: analysis, concept, and performance
NASA Astrophysics Data System (ADS)
Kastek, M.; Dulski, R.; Madura, H.; Trzaskawka, P.; Bieszczad, G.; Sosnowski, T.
2011-08-01
The paper discusses technical possibilities to build an effective electro-optical sensor unit for sniper detection using infrared cameras. This unit, comprising of thermal and daylight cameras, can operate as a standalone device but its primary application is a multi-sensor sniper and shot detection system. At first, the analysis was presented of three distinguished phases of sniper activity: before, during and after the shot. On the basis of experimental data the parameters defining the relevant sniper signatures were determined which are essential in assessing the capability of infrared camera to detect sniper activity. A sniper body and muzzle flash were analyzed as targets and the descriptions of phenomena which make it possible to detect sniper activities in infrared spectra as well as analysis of physical limitations were performed. The analyzed infrared systems were simulated using NVTherm software. The calculations for several cameras, equipped with different lenses and detector types were performed. The simulation of detection ranges was performed for the selected scenarios of sniper detection tasks. After the analysis of simulation results, the technical specifications of infrared sniper detection system were discussed, required to provide assumed detection range. Finally the infrared camera setup was proposed which can detected sniper from 1000 meters range.
Photodetectors for the Advanced Gamma-ray Imaging System (AGIS)
NASA Astrophysics Data System (ADS)
Wagner, Robert G.; Advanced Gamma-ray Imaging System AGIS Collaboration
2010-03-01
The Advanced Gamma-Ray Imaging System (AGIS) is a concept for the next generation very high energy gamma-ray observatory. Design goals include an order of magnitude better sensitivity, better angular resolution, and a lower energy threshold than existing Cherenkov telescopes. Each telescope is equipped with a camera that detects and records the Cherenkov-light flashes from air showers. The camera is comprised of a pixelated focal plane of blue sensitive and fast (nanosecond) photon detectors that detect the photon signal and convert it into an electrical one. Given the scale of AGIS, the camera must be reliable and cost effective. The Schwarzschild-Couder optical design yields a smaller plate scale than present-day Cherenkov telescopes, enabling the use of more compact, multi-pixel devices, including multianode photomultipliers or Geiger avalanche photodiodes. We present the conceptual design of the focal plane for the camera and results from testing candidate! focal plane sensors.
NASA Astrophysics Data System (ADS)
Stoykova, Elena; Gotchev, Atanas; Sainov, Ventseslav
2011-01-01
Real-time accomplishment of a phase-shifting profilometry through simultaneous projection and recording of fringe patterns requires a reliable phase retrieval procedure. In the present work we consider a four-wavelength multi-camera system with four sinusoidal phase gratings for pattern projection that implements a four-step algorithm. Successful operation of the system depends on overcoming two challenges which stem out from the inherent limitations of the phase-shifting algorithm, namely the demand for a sinusoidal fringe profile and the necessity to ensure equal background and contrast of fringes in the recorded fringe patterns. As a first task, we analyze the systematic errors due to the combined influence of the higher harmonics and multi-wavelength illumination in the Fresnel diffraction zone considering the case when the modulation parameters of the four gratings are different. As a second task we simulate the system performance to evaluate the degrading effect of the speckle noise and the spatially varying fringe modulation at non-uniform illumination on the overall accuracy of the profilometric measurement. We consider the case of non-correlated speckle realizations in the recorded fringe patterns due to four-wavelength illumination. Finally, we apply a phase retrieval procedure which includes normalization, background removal and denoising of the recorded fringe patterns to both simulated and measured data obtained for a dome surface.
Salau, J; Haas, J H; Thaller, G; Leisen, M; Junge, W
2016-09-01
Camera-based systems in dairy cattle were intensively studied over the last years. Different from this study, single camera systems with a limited range of applications were presented, mostly using 2D cameras. This study presents current steps in the development of a camera system comprising multiple 3D cameras (six Microsoft Kinect cameras) for monitoring purposes in dairy cows. An early prototype was constructed, and alpha versions of software for recording, synchronizing, sorting and segmenting images and transforming the 3D data in a joint coordinate system have already been implemented. This study introduced the application of two-dimensional wavelet transforms as method for object recognition and surface analyses. The method was explained in detail, and four differently shaped wavelets were tested with respect to their reconstruction error concerning Kinect recorded depth maps from different camera positions. The images' high frequency parts reconstructed from wavelet decompositions using the haar and the biorthogonal 1.5 wavelet were statistically analyzed with regard to the effects of image fore- or background and of cows' or persons' surface. Furthermore, binary classifiers based on the local high frequencies have been implemented to decide whether a pixel belongs to the image foreground and if it was located on a cow or a person. Classifiers distinguishing between image regions showed high (⩾0.8) values of Area Under reciever operation characteristic Curve (AUC). The classifications due to species showed maximal AUC values of 0.69.
NASA Astrophysics Data System (ADS)
Opromolla, Roberto; Fasano, Giancarmine; Rufino, Giancarlo; Grassi, Michele; Pernechele, Claudio; Dionisio, Cesare
2017-11-01
This paper presents an innovative algorithm developed for attitude determination of a space platform. The algorithm exploits images taken from a multi-purpose panoramic camera equipped with hyper-hemispheric lens and used as star tracker. The sensor architecture is also original since state-of-the-art star trackers accurately image as many stars as possible within a narrow- or medium-size field-of-view, while the considered sensor observes an extremely large portion of the celestial sphere but its observation capabilities are limited by the features of the optical system. The proposed original approach combines algorithmic concepts, like template matching and point cloud registration, inherited from the computer vision and robotic research fields, to carry out star identification. The final aim is to provide a robust and reliable initial attitude solution (lost-in-space mode), with a satisfactory accuracy level in view of the multi-purpose functionality of the sensor and considering its limitations in terms of resolution and sensitivity. Performance evaluation is carried out within a simulation environment in which the panoramic camera operation is realistically reproduced, including perturbations in the imaged star pattern. Results show that the presented algorithm is able to estimate attitude with accuracy better than 1° with a success rate around 98% evaluated by densely covering the entire space of the parameters representing the camera pointing in the inertial space.
Omnidirectional Underwater Camera Design and Calibration
Bosch, Josep; Gracias, Nuno; Ridao, Pere; Ribas, David
2015-01-01
This paper presents the development of an underwater omnidirectional multi-camera system (OMS) based on a commercially available six-camera system, originally designed for land applications. A full calibration method is presented for the estimation of both the intrinsic and extrinsic parameters, which is able to cope with wide-angle lenses and non-overlapping cameras simultaneously. This method is valid for any OMS in both land or water applications. For underwater use, a customized housing is required, which often leads to strong image distortion due to refraction among the different media. This phenomena makes the basic pinhole camera model invalid for underwater cameras, especially when using wide-angle lenses, and requires the explicit modeling of the individual optical rays. To address this problem, a ray tracing approach has been adopted to create a field-of-view (FOV) simulator for underwater cameras. The simulator allows for the testing of different housing geometries and optics for the cameras to ensure a complete hemisphere coverage in underwater operation. This paper describes the design and testing of a compact custom housing for a commercial off-the-shelf OMS camera (Ladybug 3) and presents the first results of its use. A proposed three-stage calibration process allows for the estimation of all of the relevant camera parameters. Experimental results are presented, which illustrate the performance of the calibration method and validate the approach. PMID:25774707
Ultra-compact imaging system based on multi-aperture architecture
NASA Astrophysics Data System (ADS)
Meyer, Julia; Brückner, Andreas; Leitel, Robert; Dannberg, Peter; Bräuer, Andreas; Tünnermann, Andreas
2011-03-01
As a matter of course, cameras are integrated in the field of information and communication technology. It can be observed, that there is a trend that those cameras get smaller and at the same time cheaper. Because single aperture have a limit of miniaturization, while simultaneously keeping the same space-bandwidth-product and transmitting a wide field of view, there is a need of new ideas like the multi aperture optical systems. In the proposed camera system the image is formed with many different channels each consisting of four microlenses which are arranged one after another in different microlens arrays. A partial image which fits together with the neighbouring one is formed in every single channel, so that a real erect image is generated and a conventional image sensor can be used. The microoptical fabrication process and the assembly are well established and can be carried out on wafer-level. Laser writing is used for the fabrication of the masks. UV-lithography, a reflow process and UV-molding is needed for the fabrication of the apertures and the lenses. The developed system is very small in terms of both length and lateral dimensions and has a VGA resolution and a diagonal field of view of 65 degrees. This microoptical vision system is appropriate for being implemented in electronic devices such as webcams integrated in notebookdisplays.
Design of an open-ended plenoptic camera for three-dimensional imaging of dusty plasmas
NASA Astrophysics Data System (ADS)
Sanpei, Akio; Tokunaga, Kazuya; Hayashi, Yasuaki
2017-08-01
Herein, the design of a plenoptic imaging system for three-dimensional reconstructions of dusty plasmas using an integral photography technique has been reported. This open-ended system is constructed with a multi-convex lens array and a typical reflex CMOS camera. We validated the design of the reconstruction system using known target particles. Additionally, the system has been applied to observations of fine particles floating in a horizontal, parallel-plate radio-frequency plasma. Furthermore, the system works well in the range of our dusty plasma experiment. We can identify the three-dimensional positions of dust particles from a single-exposure image obtained from one viewing port.
Camera Control and Geo-Registration for Video Sensor Networks
NASA Astrophysics Data System (ADS)
Davis, James W.
With the use of large video networks, there is a need to coordinate and interpret the video imagery for decision support systems with the goal of reducing the cognitive and perceptual overload of human operators. We present computer vision strategies that enable efficient control and management of cameras to effectively monitor wide-coverage areas, and examine the framework within an actual multi-camera outdoor urban video surveillance network. First, we construct a robust and precise camera control model for commercial pan-tilt-zoom (PTZ) video cameras. In addition to providing a complete functional control mapping for PTZ repositioning, the model can be used to generate wide-view spherical panoramic viewspaces for the cameras. Using the individual camera control models, we next individually map the spherical panoramic viewspace of each camera to a large aerial orthophotograph of the scene. The result provides a unified geo-referenced map representation to permit automatic (and manual) video control and exploitation of cameras in a coordinated manner. The combined framework provides new capabilities for video sensor networks that are of significance and benefit to the broad surveillance/security community.
Yang, Xiaofeng; Wu, Wei; Wang, Guoan
2015-04-01
This paper presents a surgical optical navigation system with non-invasive, real-time, and positioning characteristics for open surgical procedure. The design was based on the principle of near-infrared fluorescence molecular imaging. The in vivo fluorescence excitation technology, multi-channel spectral camera technology and image fusion software technology were used. Visible and near-infrared light ring LED excitation source, multi-channel band pass filters, spectral camera 2 CCD optical sensor technology and computer systems were integrated, and, as a result, a new surgical optical navigation system was successfully developed. When the near-infrared fluorescence was injected, the system could display anatomical images of the tissue surface and near-infrared fluorescent functional images of surgical field simultaneously. The system can identify the lymphatic vessels, lymph node, tumor edge which doctor cannot find out with naked eye intra-operatively. Our research will guide effectively the surgeon to remove the tumor tissue to improve significantly the success rate of surgery. The technologies have obtained a national patent, with patent No. ZI. 2011 1 0292374. 1.
NASA Astrophysics Data System (ADS)
den Hollander, Richard J. M.; Bouma, Henri; Baan, Jan; Eendebak, Pieter T.; van Rest, Jeroen H. C.
2015-10-01
Person tracking across non-overlapping cameras and other types of video analytics benefit from spatial calibration information that allows an estimation of the distance between cameras and a relation between pixel coordinates and world coordinates within a camera. In a large environment with many cameras, or for frequent ad-hoc deployments of cameras, the cost of this calibration is high. This creates a barrier for the use of video analytics. Automating the calibration allows for a short configuration time, and the use of video analytics in a wider range of scenarios, including ad-hoc crisis situations and large scale surveillance systems. We show an autocalibration method entirely based on pedestrian detections in surveillance video in multiple non-overlapping cameras. In this paper, we show the two main components of automatic calibration. The first shows the intra-camera geometry estimation that leads to an estimate of the tilt angle, focal length and camera height, which is important for the conversion from pixels to meters and vice versa. The second component shows the inter-camera topology inference that leads to an estimate of the distance between cameras, which is important for spatio-temporal analysis of multi-camera tracking. This paper describes each of these methods and provides results on realistic video data.
Tsiourlis, Georgios; Andreadakis, Stamatis; Konstantinidis, Pavlos
2009-01-01
The SITHON system, a fully wireless optical imaging system, integrating a network of in-situ optical cameras linking to a multi-layer GIS database operated by Control Operating Centres, has been developed in response to the need for early detection, notification and monitoring of forest fires. This article presents in detail the architecture and the components of SITHON, and demonstrates the first encouraging results of an experimental test with small controlled fires over Sithonia Peninsula in Northern Greece. The system has already been scheduled to be installed in some fire prone areas of Greece. PMID:22408536
Computer vision camera with embedded FPGA processing
NASA Astrophysics Data System (ADS)
Lecerf, Antoine; Ouellet, Denis; Arias-Estrada, Miguel
2000-03-01
Traditional computer vision is based on a camera-computer system in which the image understanding algorithms are embedded in the computer. To circumvent the computational load of vision algorithms, low-level processing and imaging hardware can be integrated in a single compact module where a dedicated architecture is implemented. This paper presents a Computer Vision Camera based on an open architecture implemented in an FPGA. The system is targeted to real-time computer vision tasks where low level processing and feature extraction tasks can be implemented in the FPGA device. The camera integrates a CMOS image sensor, an FPGA device, two memory banks, and an embedded PC for communication and control tasks. The FPGA device is a medium size one equivalent to 25,000 logic gates. The device is connected to two high speed memory banks, an IS interface, and an imager interface. The camera can be accessed for architecture programming, data transfer, and control through an Ethernet link from a remote computer. A hardware architecture can be defined in a Hardware Description Language (like VHDL), simulated and synthesized into digital structures that can be programmed into the FPGA and tested on the camera. The architecture of a classical multi-scale edge detection algorithm based on a Laplacian of Gaussian convolution has been developed to show the capabilities of the system.
NASA Technical Reports Server (NTRS)
Zalameda, Joseph N.; Burke, Eric R.; Hafley, Robert A.; Taminger, Karen M.; Domack, Christopher S.; Brewer, Amy R.; Martin, Richard E.
2013-01-01
Additive manufacturing is a rapidly growing field where 3-dimensional parts can be produced layer by layer. NASA s electron beam free-form fabrication (EBF(sup 3)) technology is being evaluated to manufacture metallic parts in a space environment. The benefits of EBF(sup 3) technology are weight savings to support space missions, rapid prototyping in a zero gravity environment, and improved vehicle readiness. The EBF(sup 3) system is composed of 3 main components: electron beam gun, multi-axis position system, and metallic wire feeder. The electron beam is used to melt the wire and the multi-axis positioning system is used to build the part layer by layer. To insure a quality weld, a near infrared (NIR) camera is used to image the melt pool and solidification areas. This paper describes the calibration and application of a NIR camera for temperature measurement. In addition, image processing techniques are presented for weld assessment metrics.
A small field of view camera for hybrid gamma and optical imaging
NASA Astrophysics Data System (ADS)
Lees, J. E.; Bugby, S. L.; Bhatia, B. S.; Jambi, L. K.; Alqahtani, M. S.; McKnight, W. R.; Ng, A. H.; Perkins, A. C.
2014-12-01
The development of compact low profile gamma-ray detectors has allowed the production of small field of view, hand held imaging devices for use at the patient bedside and in operating theatres. The combination of an optical and a gamma camera, in a co-aligned configuration, offers high spatial resolution multi-modal imaging giving a superimposed scintigraphic and optical image. This innovative introduction of hybrid imaging offers new possibilities for assisting surgeons in localising the site of uptake in procedures such as sentinel node detection. Recent improvements to the camera system along with results of phantom and clinical imaging are reported.
Fabrication of multi-focal microlens array on curved surface for wide-angle camera module
NASA Astrophysics Data System (ADS)
Pan, Jun-Gu; Su, Guo-Dung J.
2017-08-01
In this paper, we present a wide-angle and compact camera module that consists of microlens array with different focal lengths on curved surface. The design integrates the principle of an insect's compound eye and the human eye. It contains a curved hexagonal microlens array and a spherical lens. Compared with normal mobile phone cameras which usually need no less than four lenses, but our proposed system only uses one lens. Furthermore, the thickness of our proposed system is only 2.08 mm and diagonal full field of view is about 100 degrees. In order to make the critical microlens array, we used the inkjet printing to control the surface shape of each microlens for achieving different focal lengths and use replication method to form curved hexagonal microlens array.
Marker-less multi-frame motion tracking and compensation in PET-brain imaging
NASA Astrophysics Data System (ADS)
Lindsay, C.; Mukherjee, J. M.; Johnson, K.; Olivier, P.; Song, X.; Shao, L.; King, M. A.
2015-03-01
In PET brain imaging, patient motion can contribute significantly to the degradation of image quality potentially leading to diagnostic and therapeutic problems. To mitigate the image artifacts resulting from patient motion, motion must be detected and tracked then provided to a motion correction algorithm. Existing techniques to track patient motion fall into one of two categories: 1) image-derived approaches and 2) external motion tracking (EMT). Typical EMT requires patients to have markers in a known pattern on a rigid too attached to their head, which are then tracked by expensive and bulky motion tracking camera systems or stereo cameras. This has made marker-based EMT unattractive for routine clinical application. Our main contributions are the development of a marker-less motion tracking system that uses lowcost, small depth-sensing cameras which can be installed in the bore of the imaging system. Our motion tracking system does not require anything to be attached to the patient and can track the rigid transformation (6-degrees of freedom) of the patient's head at a rate 60 Hz. We show that our method can not only be used in with Multi-frame Acquisition (MAF) PET motion correction, but precise timing can be employed to determine only the necessary frames needed for correction. This can speeds up reconstruction by eliminating the unnecessary subdivision of frames.
Systems for increasing the sensitivity of gamma-ray imagers
Mihailescu, Lucian; Vetter, Kai M.; Chivers, Daniel H.
2012-12-11
Systems that increase the position resolution and granularity of double sided segmented semiconductor detectors are provided. These systems increase the imaging resolution capability of such detectors, either used as Compton cameras, or as position sensitive radiation detectors in imagers such as SPECT, PET, coded apertures, multi-pinhole imagers, or other spatial or temporal modulated imagers.
CICADA -- Configurable Instrument Control and Data Acquisition
NASA Astrophysics Data System (ADS)
Young, Peter J.; Roberts, William H.; Sebo, Kim M.
CICADA (Young et al. 1997) is a multi-process, distributed application for the control of astronomical data acquisition systems. It comprises elements that control the operation of, and data flow from CCD camera systems; and the operation of telescope instrument control systems. CICADA can be used to dynamically configure support for astronomical instruments that can be made up of multiple cameras and multiple instrument controllers. Each camera is described by a hierarchy of parts that are each individually configured and linked together. Most of CICADA is written in C++ and much of the configurability of CICADA comes from the use of inheritance and polymorphism. An example of a multiple part instrument configuration -- a wide field imager (WFI) -- is described here. WFI, presently under construction, is made up of eight 2k x 4k CCDs with dual SDSU II controllers and will be used at Siding Spring's ANU 40in and AAO 3.9m telescopes.
Report Of The HST Strategy Panel: A Strategy For Recovery
1991-01-01
orbit change out: the Wide Field/Planetary Camera II (WFPC II), the Near-Infrared Camera and Multi- Object Spectrometer (NICMOS) and the Space ...are the Space Telescope Imaging Spectrograph (STB), the Near-Infrared Camera and Multi- Object Spectrom- eter (NICMOS), and the second Wide Field and...expected to fail to lock due to duplicity was 20%; on- orbit data indicates that 10% may be a better estimate, but the guide stars were preselected
Design and development of an airborne multispectral imaging system
NASA Astrophysics Data System (ADS)
Kulkarni, Rahul R.; Bachnak, Rafic; Lyle, Stacey; Steidley, Carl W.
2002-08-01
Advances in imaging technology and sensors have made airborne remote sensing systems viable for many applications that require reasonably good resolution at low cost. Digital cameras are making their mark on the market by providing high resolution at very high rates. This paper describes an aircraft-mounted imaging system (AMIS) that is being designed and developed at Texas A&M University-Corpus Christi (A&M-CC) with the support of a grant from NASA. The approach is to first develop and test a one-camera system that will be upgraded into a five-camera system that offers multi-spectral capabilities. AMIS will be low cost, rugged, portable and has its own battery power source. Its immediate use will be to acquire images of the Coastal area in the Gulf of Mexico for a variety of studies covering vast spectra from near ultraviolet region to near infrared region. This paper describes AMIS and its characteristics, discusses the process for selecting the major components, and presents the progress.
An Overview of the CBERS-2 Satellite and Comparison of the CBERS-2 CCD Data with the L5 TM Data
NASA Technical Reports Server (NTRS)
Chandler, Gyanesh
2007-01-01
CBERS satellite carries on-board a multi sensor payload with different spatial resolutions and collection frequencies. HRCCD (High Resolution CCD Camera), IRMSS (Infrared Multispectral Scanner), and WFI (Wide-Field Imager). The CCD and the WFI camera operate in the VNIR regions, while the IRMSS operates in SWIR and thermal region. In addition to the imaging payload, the satellite carries a Data Collection System (DCS) and Space Environment Monitor (SEM).
Dual Beam System (SEM/FIB) Equipment for the Kleberg Advanced Microscopy Center
2015-06-05
Journal of Applied Physics (04 2015) John E. Sanchez, Ramón Díaz de León, Fernando Mendoza Santoyo, Gabriel González, Miguel José Yacaman, Arturo Ponce...includes PCs and cameras , will have available support for three years. What is Not Covered: This Warranty does not cover high-wear, consumable...110 x 110 mm eucentric stage - Multi-purpose holder - CCD IR camera - In-lens detectors: Lower (T1) and Upper (T2) - SE detector (ET-SED
MS Grunsfeld wearing EMU in Airlock
2002-03-08
STS109-E-5721 (8 March 2002) --- Astronaut John M. Grunsfeld, STS-109 payload commander, attired in the extravehicular mobility unit (EMU) space suit, completed suited is in the Space Shuttle Columbias airlock. Grunsfeld and Richard M. Linnehan, mission specialist, were about to participate in STS-109s fifth space walk. Activities for EVA-5 centered around the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) to install a Cryogenic Cooler and its Cooling System Radiator. The image was recorded with a digital still camera.
MS Grunsfeld wearing EMU in Airlock joined by MS Newman and Massimino
2002-03-08
STS109-E-5722 (8 March 2002) --- Astronaut John M. Grunsfeld (center), STS-109 payload commander, attired in the extravehicular mobility unit (EMU) space suit, is photographed with astronauts James H. Newman (left) and Michael J. Massimino, both mission specialists, prior to the fifth space walk. Activities for EVA-5 centered around the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) to install a Cryogenic Cooler and its Cooling System Radiator. The image was recorded with a digital still camera.
Distributed video data fusion and mining
NASA Astrophysics Data System (ADS)
Chang, Edward Y.; Wang, Yuan-Fang; Rodoplu, Volkan
2004-09-01
This paper presents an event sensing paradigm for intelligent event-analysis in a wireless, ad hoc, multi-camera, video surveillance system. In particilar, we present statistical methods that we have developed to support three aspects of event sensing: 1) energy-efficient, resource-conserving, and robust sensor data fusion and analysis, 2) intelligent event modeling and recognition, and 3) rapid deployment, dynamic configuration, and continuous operation of the camera networks. We outline our preliminary results, and discuss future directions that research might take.
NASA Technical Reports Server (NTRS)
Drummond, Mark; Hine, Butler; Genet, Russell; Genet, David; Talent, David; Boyd, Louis; Trueblood, Mark; Filippenko, Alexei V. (Editor)
1991-01-01
The objective of multi-use telescopes is to reduce the initial and operational costs of space telescopes to the point where a fair number of telescopes, a dozen or so, would be affordable. The basic approach is to develop a common telescope, control system, and power and communications subsystem that can be used with a wide variety of instrument payloads, i.e., imaging CCD cameras, photometers, spectrographs, etc. By having such a multi-use and multi-user telescope, a common practice for earth-based telescopes, development cost can be shared across many telescopes, and the telescopes can be produced in economical batches.
Multiple Sensor Camera for Enhanced Video Capturing
NASA Astrophysics Data System (ADS)
Nagahara, Hajime; Kanki, Yoshinori; Iwai, Yoshio; Yachida, Masahiko
A resolution of camera has been drastically improved under a current request for high-quality digital images. For example, digital still camera has several mega pixels. Although a video camera has the higher frame-rate, the resolution of a video camera is lower than that of still camera. Thus, the high-resolution is incompatible with the high frame rate of ordinary cameras in market. It is difficult to solve this problem by a single sensor, since it comes from physical limitation of the pixel transfer rate. In this paper, we propose a multi-sensor camera for capturing a resolution and frame-rate enhanced video. Common multi-CCDs camera, such as 3CCD color camera, has same CCD for capturing different spectral information. Our approach is to use different spatio-temporal resolution sensors in a single camera cabinet for capturing higher resolution and frame-rate information separately. We build a prototype camera which can capture high-resolution (2588×1958 pixels, 3.75 fps) and high frame-rate (500×500, 90 fps) videos. We also proposed the calibration method for the camera. As one of the application of the camera, we demonstrate an enhanced video (2128×1952 pixels, 90 fps) generated from the captured videos for showing the utility of the camera.
Multiple-aperture optical design for micro-level cameras using 3D-printing method
NASA Astrophysics Data System (ADS)
Peng, Wei-Jei; Hsu, Wei-Yao; Cheng, Yuan-Chieh; Lin, Wen-Lung; Yu, Zong-Ru; Chou, Hsiao-Yu; Chen, Fong-Zhi; Fu, Chien-Chung; Wu, Chong-Syuan; Huang, Chao-Tsung
2018-02-01
The design of the ultra miniaturized camera using 3D-printing technology directly printed on to the complementary metal-oxide semiconductor (CMOS) imaging sensor is presented in this paper. The 3D printed micro-optics is manufactured using the femtosecond two-photon direct laser writing, and the figure error which could achieve submicron accuracy is suitable for the optical system. Because the size of the micro-level camera is approximately several hundreds of micrometers, the resolution is reduced much and highly limited by the Nyquist frequency of the pixel pitch. For improving the reduced resolution, one single-lens can be replaced by multiple-aperture lenses with dissimilar field of view (FOV), and then stitching sub-images with different FOV can achieve a high resolution within the central region of the image. The reason is that the angular resolution of the lens with smaller FOV is higher than that with larger FOV, and then the angular resolution of the central area can be several times than that of the outer area after stitching. For the same image circle, the image quality of the central area of the multi-lens system is significantly superior to that of a single-lens. The foveated image using stitching FOV breaks the limitation of the resolution for the ultra miniaturized imaging system, and then it can be applied such as biomedical endoscopy, optical sensing, and machine vision, et al. In this study, the ultra miniaturized camera with multi-aperture optics is designed and simulated for the optimum optical performance.
Accuracy Potential and Applications of MIDAS Aerial Oblique Camera System
NASA Astrophysics Data System (ADS)
Madani, M.
2012-07-01
Airborne oblique cameras such as Fairchild T-3A were initially used for military reconnaissance in 30s. A modern professional digital oblique camera such as MIDAS (Multi-camera Integrated Digital Acquisition System) is used to generate lifelike three dimensional to the users for visualizations, GIS applications, architectural modeling, city modeling, games, simulators, etc. Oblique imagery provide the best vantage for accessing and reviewing changes to the local government tax base, property valuation assessment, buying & selling of residential/commercial for better decisions in a more timely manner. Oblique imagery is also used for infrastructure monitoring making sure safe operations of transportation, utilities, and facilities. Sanborn Mapping Company acquired one MIDAS from TrackAir in 2011. This system consists of four tilted (45 degrees) cameras and one vertical camera connected to a dedicated data acquisition computer system. The 5 digital cameras are based on the Canon EOS 1DS Mark3 with Zeiss lenses. The CCD size is 5,616 by 3,744 (21 MPixels) with the pixel size of 6.4 microns. Multiple flights using different camera configurations (nadir/oblique (28 mm/50 mm) and (50 mm/50 mm)) were flown over downtown Colorado Springs, Colorado. Boresight fights for 28 mm nadir camera were flown at 600 m and 1,200 m and for 50 mm nadir camera at 750 m and 1500 m. Cameras were calibrated by using a 3D cage and multiple convergent images utilizing Australis model. In this paper, the MIDAS system is described, a number of real data sets collected during the aforementioned flights are presented together with their associated flight configurations, data processing workflow, system calibration and quality control workflows are highlighted and the achievable accuracy is presented in some detail. This study revealed that the expected accuracy of about 1 to 1.5 GSD (Ground Sample Distance) for planimetry and about 2 to 2.5 GSD for vertical can be achieved. Remaining systematic errors were modeled by analyzing residuals using correction grid. The results of the final bundle adjustments are sufficient to enable Sanborn to produce DEM/DTM and orthophotos from the nadir imagery and create 3D models using georeferenced oblique imagery.
Simultaneous Calibration: A Joint Optimization Approach for Multiple Kinect and External Cameras.
Liao, Yajie; Sun, Ying; Li, Gongfa; Kong, Jianyi; Jiang, Guozhang; Jiang, Du; Cai, Haibin; Ju, Zhaojie; Yu, Hui; Liu, Honghai
2017-06-24
Camera calibration is a crucial problem in many applications, such as 3D reconstruction, structure from motion, object tracking and face alignment. Numerous methods have been proposed to solve the above problem with good performance in the last few decades. However, few methods are targeted at joint calibration of multi-sensors (more than four devices), which normally is a practical issue in the real-time systems. In this paper, we propose a novel method and a corresponding workflow framework to simultaneously calibrate relative poses of a Kinect and three external cameras. By optimizing the final cost function and adding corresponding weights to the external cameras in different locations, an effective joint calibration of multiple devices is constructed. Furthermore, the method is tested in a practical platform, and experiment results show that the proposed joint calibration method can achieve a satisfactory performance in a project real-time system and its accuracy is higher than the manufacturer's calibration.
Simultaneous Calibration: A Joint Optimization Approach for Multiple Kinect and External Cameras
Liao, Yajie; Sun, Ying; Li, Gongfa; Kong, Jianyi; Jiang, Guozhang; Jiang, Du; Cai, Haibin; Ju, Zhaojie; Yu, Hui; Liu, Honghai
2017-01-01
Camera calibration is a crucial problem in many applications, such as 3D reconstruction, structure from motion, object tracking and face alignment. Numerous methods have been proposed to solve the above problem with good performance in the last few decades. However, few methods are targeted at joint calibration of multi-sensors (more than four devices), which normally is a practical issue in the real-time systems. In this paper, we propose a novel method and a corresponding workflow framework to simultaneously calibrate relative poses of a Kinect and three external cameras. By optimizing the final cost function and adding corresponding weights to the external cameras in different locations, an effective joint calibration of multiple devices is constructed. Furthermore, the method is tested in a practical platform, and experiment results show that the proposed joint calibration method can achieve a satisfactory performance in a project real-time system and its accuracy is higher than the manufacturer’s calibration. PMID:28672823
Efficient large-scale graph data optimization for intelligent video surveillance
NASA Astrophysics Data System (ADS)
Shang, Quanhong; Zhang, Shujun; Wang, Yanbo; Sun, Chen; Wang, Zepeng; Zhang, Luming
2017-08-01
Society is rapidly accepting the use of a wide variety of cameras Location and applications: site traffic monitoring, parking Lot surveillance, car and smart space. These ones here the camera provides data every day in an analysis Effective way. Recent advances in sensor technology Manufacturing, communications and computing are stimulating.The development of new applications that can change the traditional Vision system incorporating universal smart camera network. This Analysis of visual cues in multi camera networks makes wide Applications ranging from smart home and office automation to large area surveillance and traffic surveillance. In addition, dense Camera networks, most of which have large overlapping areas of cameras. In the view of good research, we focus on sparse camera networks. One Sparse camera network using large area surveillance. As few cameras as possible, most cameras do not overlap Each other’s field of vision. This task is challenging Lack of knowledge of topology Network, the specific changes in appearance and movement Track different opinions of the target, as well as difficulties Understanding complex events in a network. In this review in this paper, we present a comprehensive survey of recent studies Results to solve the problem of topology learning, Object appearance modeling and global activity understanding sparse camera network. In addition, some of the current open Research issues are discussed.
Nekton Interaction Monitoring System
DOE Office of Scientific and Technical Information (OSTI.GOV)
2017-03-15
The software provides a real-time processing system for sonar to detect and track animals, and to extract water column biomass statistics in order to facilitate continuous monitoring of an underwater environment. The Nekton Interaction Monitoring System (NIMS) extracts and archives tracking and backscatter statistics data from a real-time stream of data from a sonar device. NIMS also sends real-time tracking messages over the network that can be used by other systems to generate other metrics or to trigger instruments such as an optical video camera. A web-based user interface provides remote monitoring and control. NIMS currently supports three popular sonarmore » devices: M3 multi-beam sonar (Kongsberg), EK60 split-beam echo-sounder (Simrad) and BlueView acoustic camera (Teledyne).« less
2001-12-01
KENNEDY SPACE CENTER, Fla. - STS-109 Mission Specialist Richard Lennehan (left) and Payload Commander John Grunsfeld get a feel for tools and equipment that will be used on the mission. The crew is at KSC to take part in Crew Equipment Interface Test activities that include familiarization with the orbiter and equipment. The goal of the mission is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the Advanced Camera for Surveys, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002
QWIP technology for both military and civilian applications
NASA Astrophysics Data System (ADS)
Gunapala, Sarath D.; Kukkonen, Carl A.; Sirangelo, Mark N.; McQuiston, Barbara K.; Chehayeb, Riad; Kaufmann, M.
2001-10-01
Advanced thermal imaging infrared cameras have been a cost effective and reliable method to obtain the temperature of objects. Quantum Well Infrared Photodetector (QWIP) based thermal imaging systems have advanced the state-of-the-art and are the most sensitive commercially available thermal systems. QWIP Technologies LLC, under exclusive agreement with Caltech University, is currently manufacturing the QWIP-ChipTM, a 320 X 256 element, bound-to-quasibound QWIP FPA. The camera performance falls within the long-wave IR band, spectrally peaked at 8.5 μm. The camera is equipped with a 32-bit floating-point digital signal processor combined with multi- tasking software, delivering a digital acquisition resolution of 12-bits using nominal power consumption of less than 50 Watts. With a variety of video interface options, remote control capability via an RS-232 connection, and an integrated control driver circuit to support motorized zoom and focus- compatible lenses, this camera design has excellent application in both the military and commercial sector. In the area of remote sensing, high-performance QWIP systems can be used for high-resolution, target recognition as part of a new system of airborne platforms (including UAVs). Such systems also have direct application in law enforcement, surveillance, industrial monitoring and road hazard detection systems. This presentation will cover the current performance of the commercial QWIP cameras, conceptual platform systems and advanced image processing for use in both military remote sensing and civilian applications currently being developed in road hazard monitoring.
Intelligent viewing control for robotic and automation systems
NASA Astrophysics Data System (ADS)
Schenker, Paul S.; Peters, Stephen F.; Paljug, Eric D.; Kim, Won S.
1994-10-01
We present a new system for supervisory automated control of multiple remote cameras. Our primary purpose in developing this system has been to provide capability for knowledge- based, `hands-off' viewing during execution of teleoperation/telerobotic tasks. The reported technology has broader applicability to remote surveillance, telescience observation, automated manufacturing workcells, etc. We refer to this new capability as `Intelligent Viewing Control (IVC),' distinguishing it from a simple programmed camera motion control. In the IVC system, camera viewing assignment, sequencing, positioning, panning, and parameter adjustment (zoom, focus, aperture, etc.) are invoked and interactively executed by real-time by a knowledge-based controller, drawing on a priori known task models and constraints, including operator preferences. This multi-camera control is integrated with a real-time, high-fidelity 3D graphics simulation, which is correctly calibrated in perspective to the actual cameras and their platform kinematics (translation/pan-tilt). Such merged graphics- with-video design allows the system user to preview and modify the planned (`choreographed') viewing sequences. Further, during actual task execution, the system operator has available both the resulting optimized video sequence, as well as supplementary graphics views from arbitrary perspectives. IVC, including operator-interactive designation of robot task actions, is presented to the user as a well-integrated video-graphic single screen user interface allowing easy access to all relevant telerobot communication/command/control resources. We describe and show pictorial results of a preliminary IVC system implementation for telerobotic servicing of a satellite.
High-precision method of binocular camera calibration with a distortion model.
Li, Weimin; Shan, Siyu; Liu, Hui
2017-03-10
A high-precision camera calibration method for binocular stereo vision system based on a multi-view template and alternative bundle adjustment is presented in this paper. The proposed method could be achieved by taking several photos on a specially designed calibration template that has diverse encoded points in different orientations. In this paper, the method utilized the existing algorithm used for monocular camera calibration to obtain the initialization, which involves a camera model, including radial lens distortion and tangential distortion. We created a reference coordinate system based on the left camera coordinate to optimize the intrinsic parameters of left camera through alternative bundle adjustment to obtain optimal values. Then, optimal intrinsic parameters of the right camera can be obtained through alternative bundle adjustment when we create a reference coordinate system based on the right camera coordinate. We also used all intrinsic parameters that were acquired to optimize extrinsic parameters. Thus, the optimal lens distortion parameters and intrinsic and extrinsic parameters were obtained. Synthetic and real data were used to test the method. The simulation results demonstrate that the maximum mean absolute relative calibration errors are about 3.5e-6 and 1.2e-6 for the focal length and the principal point, respectively, under zero-mean Gaussian noise with 0.05 pixels standard deviation. The real result shows that the reprojection error of our model is about 0.045 pixels with the relative standard deviation of 1.0e-6 over the intrinsic parameters. The proposed method is convenient, cost-efficient, highly precise, and simple to carry out.
The purpose of the field demonstration program is to gather technically reliable cost and performance information on selected condition assessment technologies under defined field conditions. The selected technologies include zoom camera, focused electrode leak location (FELL), ...
NASA Astrophysics Data System (ADS)
Mundhenk, Terrell N.; Dhavale, Nitin; Marmol, Salvador; Calleja, Elizabeth; Navalpakkam, Vidhya; Bellman, Kirstie; Landauer, Chris; Arbib, Michael A.; Itti, Laurent
2003-10-01
In view of the growing complexity of computational tasks and their design, we propose that certain interactive systems may be better designed by utilizing computational strategies based on the study of the human brain. Compared with current engineering paradigms, brain theory offers the promise of improved self-organization and adaptation to the current environment, freeing the programmer from having to address those issues in a procedural manner when designing and implementing large-scale complex systems. To advance this hypothesis, we discus a multi-agent surveillance system where 12 agent CPUs each with its own camera, compete and cooperate to monitor a large room. To cope with the overload of image data streaming from 12 cameras, we take inspiration from the primate"s visual system, which allows the animal to operate a real-time selection of the few most conspicuous locations in visual input. This is accomplished by having each camera agent utilize the bottom-up, saliency-based visual attention algorithm of Itti and Koch (Vision Research 2000;40(10-12):1489-1506) to scan the scene for objects of interest. Real time operation is achieved using a distributed version that runs on a 16-CPU Beowulf cluster composed of the agent computers. The algorithm guides cameras to track and monitor salient objects based on maps of color, orientation, intensity, and motion. To spread camera view points or create cooperation in monitoring highly salient targets, camera agents bias each other by increasing or decreasing the weight of different feature vectors in other cameras, using mechanisms similar to excitation and suppression that have been documented in electrophysiology, psychophysics and imaging studies of low-level visual processing. In addition, if cameras need to compete for computing resources, allocation of computational time is weighed based upon the history of each camera. A camera agent that has a history of seeing more salient targets is more likely to obtain computational resources. The system demonstrates the viability of biologically inspired systems in a real time tracking. In future work we plan on implementing additional biological mechanisms for cooperative management of both the sensor and processing resources in this system that include top down biasing for target specificity as well as novelty and the activity of the tracked object in relation to sensitive features of the environment.
Multi-acoustic lens design methodology for a low cost C-scan photoacoustic imaging camera
NASA Astrophysics Data System (ADS)
Chinni, Bhargava; Han, Zichao; Brown, Nicholas; Vallejo, Pedro; Jacobs, Tess; Knox, Wayne; Dogra, Vikram; Rao, Navalgund
2016-03-01
We have designed and implemented a novel acoustic lens based focusing technology into a prototype photoacoustic imaging camera. All photoacoustically generated waves from laser exposed absorbers within a small volume get focused simultaneously by the lens onto an image plane. We use a multi-element ultrasound transducer array to capture the focused photoacoustic signals. Acoustic lens eliminates the need for expensive data acquisition hardware systems, is faster compared to electronic focusing and enables real-time image reconstruction. Using this photoacoustic imaging camera, we have imaged more than 150 several centimeter size ex-vivo human prostate, kidney and thyroid specimens with a millimeter resolution for cancer detection. In this paper, we share our lens design strategy and how we evaluate the resulting quality metrics (on and off axis point spread function, depth of field and modulation transfer function) through simulation. An advanced toolbox in MATLAB was adapted and used for simulating a two-dimensional gridded model that incorporates realistic photoacoustic signal generation and acoustic wave propagation through the lens with medium properties defined on each grid point. Two dimensional point spread functions have been generated and compared with experiments to demonstrate the utility of our design strategy. Finally we present results from work in progress on the use of two lens system aimed at further improving some of the quality metrics of our system.
NASA Astrophysics Data System (ADS)
Kim, Min Young; Cho, Hyung Suck; Kim, Jae H.
2002-10-01
In recent years, intelligent autonomous mobile robots have drawn tremendous interests as service robots for serving human or industrial robots for replacing human. To carry out the task, robots must be able to sense and recognize 3D space that they live or work. In this paper, we deal with the topic related to 3D sensing system for the environment recognition of mobile robots. For this, the structured lighting is basically utilized for a 3D visual sensor system because of the robustness on the nature of the navigation environment and the easy extraction of feature information of interest. The proposed sensing system is classified into a trinocular vision system, which is composed of the flexible multi-stripe laser projector, and two cameras. The principle of extracting the 3D information is based on the optical triangulation method. With modeling the projector as another camera and using the epipolar constraints which the whole cameras makes, the point-to-point correspondence between the line feature points in each image is established. In this work, the principle of this sensor is described in detail, and a series of experimental tests is performed to show the simplicity and efficiency and accuracy of this sensor system for 3D the environment sensing and recognition.
Towards designing an optical-flow based colonoscopy tracking algorithm: a comparative study
NASA Astrophysics Data System (ADS)
Liu, Jianfei; Subramanian, Kalpathi R.; Yoo, Terry S.
2013-03-01
Automatic co-alignment of optical and virtual colonoscopy images can supplement traditional endoscopic procedures, by providing more complete information of clinical value to the gastroenterologist. In this work, we present a comparative analysis of our optical flow based technique for colonoscopy tracking, in relation to current state of the art methods, in terms of tracking accuracy, system stability, and computational efficiency. Our optical-flow based colonoscopy tracking algorithm starts with computing multi-scale dense and sparse optical flow fields to measure image displacements. Camera motion parameters are then determined from optical flow fields by employing a Focus of Expansion (FOE) constrained egomotion estimation scheme. We analyze the design choices involved in the three major components of our algorithm: dense optical flow, sparse optical flow, and egomotion estimation. Brox's optical flow method,1 due to its high accuracy, was used to compare and evaluate our multi-scale dense optical flow scheme. SIFT6 and Harris-affine features7 were used to assess the accuracy of the multi-scale sparse optical flow, because of their wide use in tracking applications; the FOE-constrained egomotion estimation was compared with collinear,2 image deformation10 and image derivative4 based egomotion estimation methods, to understand the stability of our tracking system. Two virtual colonoscopy (VC) image sequences were used in the study, since the exact camera parameters(for each frame) were known; dense optical flow results indicated that Brox's method was superior to multi-scale dense optical flow in estimating camera rotational velocities, but the final tracking errors were comparable, viz., 6mm vs. 8mm after the VC camera traveled 110mm. Our approach was computationally more efficient, averaging 7.2 sec. vs. 38 sec. per frame. SIFT and Harris affine features resulted in tracking errors of up to 70mm, while our sparse optical flow error was 6mm. The comparison among egomotion estimation algorithms showed that our FOE-constrained egomotion estimation method achieved the optimal balance between tracking accuracy and robustness. The comparative study demonstrated that our optical-flow based colonoscopy tracking algorithm maintains good accuracy and stability for routine use in clinical practice.
Design of optical axis jitter control system for multi beam lasers based on FPGA
NASA Astrophysics Data System (ADS)
Ou, Long; Li, Guohui; Xie, Chuanlin; Zhou, Zhiqiang
2018-02-01
A design of optical axis closed-loop control system for multi beam lasers coherent combining based on FPGA was introduced. The system uses piezoelectric ceramics Fast Steering Mirrors (FSM) as actuator, the Fairfield spot detection of multi beam lasers by the high speed CMOS camera for optical detecting, a control system based on FPGA for real-time optical axis jitter suppression. The algorithm for optical axis centroid detecting and PID of anti-Integral saturation were realized by FPGA. Optimize the structure of logic circuit by reuse resource and pipeline, as a result of reducing logic resource but reduced the delay time, and the closed-loop bandwidth increases to 100Hz. The jitter of laser less than 40Hz was reduced 40dB. The cost of the system is low but it works stably.
NASA Astrophysics Data System (ADS)
Lin, Hsin-Hon; Chang, Hao-Ting; Chao, Tsi-Chian; Chuang, Keh-Shih
2017-08-01
In vivo range verification plays an important role in proton therapy to fully utilize the benefits of the Bragg peak (BP) for delivering high radiation dose to tumor, while sparing the normal tissue. For accurately locating the position of BP, camera equipped with collimators (multi-slit and knife-edge collimator) to image prompt gamma (PG) emitted along the proton tracks in the patient have been proposed for range verification. The aim of the work is to compare the performance of multi-slit collimator and knife-edge collimator for non-invasive proton beam range verification. PG imaging was simulated by a validated GATE/GEANT4 Monte Carlo code to model the spot-scanning proton therapy and cylindrical PMMA phantom in detail. For each spot, 108 protons were simulated. To investigate the correlation between the acquired PG profile and the proton range, the falloff regions of PG profiles were fitted with a 3-line-segment curve function as the range estimate. Factors including the energy window setting, proton energy, phantom size, and phantom shift that may influence the accuracy of detecting range were studied. Results indicated that both collimator systems achieve reasonable accuracy and good response to the phantom shift. The accuracy of range predicted by multi-slit collimator system is less affected by the proton energy, while knife-edge collimator system can achieve higher detection efficiency that lead to a smaller deviation in predicting range. We conclude that both collimator systems have potentials for accurately range monitoring in proton therapy. It is noted that neutron contamination has a marked impact on range prediction of the two systems, especially in multi-slit system. Therefore, a neutron reduction technique for improving the accuracy of range verification of proton therapy is needed.
Sugimura, Daisuke; Kobayashi, Suguru; Hamamoto, Takayuki
2017-11-01
Light field imaging is an emerging technique that is employed to realize various applications such as multi-viewpoint imaging, focal-point changing, and depth estimation. In this paper, we propose a concept of a dual-resolution light field imaging system to synthesize super-resolved multi-viewpoint images. The key novelty of this study is the use of an organic photoelectric conversion film (OPCF), which is a device that converts spectra information of incoming light within a certain wavelength range into an electrical signal (pixel value), for light field imaging. In our imaging system, we place the OPCF having the green spectral sensitivity onto the micro-lens array of the conventional light field camera. The OPCF allows us to acquire the green spectra information only at the center viewpoint with the full resolution of the image sensor. In contrast, the optical system of the light field camera in our imaging system captures the other spectra information (red and blue) at multiple viewpoints (sub-aperture images) but with low resolution. Thus, our dual-resolution light field imaging system enables us to simultaneously capture information about the target scene at a high spatial resolution as well as the direction information of the incoming light. By exploiting these advantages of our imaging system, our proposed method enables the synthesis of full-resolution multi-viewpoint images. We perform experiments using synthetic images, and the results demonstrate that our method outperforms other previous methods.
Conceptual design for an AIUC multi-purpose spectrograph camera using DMD technology
NASA Astrophysics Data System (ADS)
Rukdee, S.; Bauer, F.; Drass, H.; Vanzi, L.; Jordan, A.; Barrientos, F.
2017-02-01
Current and upcoming massive astronomical surveys are expected to discover a torrent of objects, which need groundbased follow-up observations to characterize their nature. For transient objects in particular, rapid early and efficient spectroscopic identification is needed. In particular, a small-field Integral Field Unit (IFU) would mitigate traditional slit losses and acquisition time. To this end, we present the design of a Digital Micromirror Device (DMD) multi-purpose spectrograph camera capable of running in several modes: traditional longslit, small-field patrol IFU, multi-object and full-field IFU mode via Hadamard spectra reconstruction. AIUC Optical multi-purpose CAMera (AIUCOCAM) is a low-resolution spectrograph camera of R 1,600 covering the spectral range of 0.45-0.85 μm. We employ a VPH grating as a disperser, which is removable to allow an imaging mode. This spectrograph is envisioned for use on a 1-2 m class telescope in Chile to take advantage of good site conditions. We present design decisions and challenges for a costeffective robotized spectrograph. The resulting instrument is remarkably versatile, capable of addressing a wide range of scientific topics.
Assessment of skin wound healing with a multi-aperture camera
NASA Astrophysics Data System (ADS)
Nabili, Marjan; Libin, Alex; Kim, Loan; Groah, Susan; Ramella-Roman, Jessica C.
2009-02-01
A clinical trial was conducted at the National Rehabilitation Hospital on 15 individuals to assess whether Rheparan Skin, a bio-engineered component of the extracellular matrix of the skin, is effective at promoting healing of a variety of wounds. Along with standard clinical outcome measures, a spectroscopic camera was used to assess the efficacy of Rheparan skin. Gauzes soaked with Rheparan skin were placed on volunteers wounds for 5 minutes twice weekly for four weeks. Images of the wounds were taken using a multi spectral camera and a digital camera at baseline and weekly thereafter. Spectral images collected at different wavelengths were used combined with optical skin models to quantify parameters of interest such as oxygen saturation (SO2), water content, and melanin concentration. A digital wound measurement system (VERG) was also used to measure the size of the wound. 9 of the 15 measured subjects showed a definitive improvement post treatment in the form of a decrease in wound area. 7 of these 9 individuals also showed an increase in oxygen saturation in the ulcerated area during the trial. A similar trend was seen in other metrics. Spectral imaging of skin wound can be a valuable tool to establish wound-healing trends and to clarify healing mechanisms.
Multi-Angle Snowflake Camera Instrument Handbook
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stuefer, Martin; Bailey, J.
2016-07-01
The Multi-Angle Snowflake Camera (MASC) takes 9- to 37-micron resolution stereographic photographs of free-falling hydrometers from three angles, while simultaneously measuring their fall speed. Information about hydrometeor size, shape orientation, and aspect ratio is derived from MASC photographs. The instrument consists of three commercial cameras separated by angles of 36º. Each camera field of view is aligned to have a common single focus point about 10 cm distant from the cameras. Two near-infrared emitter pairs are aligned with the camera’s field of view within a 10-angular ring and detect hydrometeor passage, with the lower emitters configured to trigger the MASCmore » cameras. The sensitive IR motion sensors are designed to filter out slow variations in ambient light. Fall speed is derived from successive triggers along the fall path. The camera exposure times are extremely short, in the range of 1/25,000th of a second, enabling the MASC to capture snowflake sizes ranging from 30 micrometers to 3 cm.« less
Innovative Camera and Image Processing System to Characterize Cryospheric Changes
NASA Astrophysics Data System (ADS)
Schenk, A.; Csatho, B. M.; Nagarajan, S.
2010-12-01
The polar regions play an important role in Earth’s climatic and geodynamic systems. Digital photogrammetric mapping provides a means for monitoring the dramatic changes observed in the polar regions during the past decades. High-resolution, photogrammetrically processed digital aerial imagery provides complementary information to surface measurements obtained by laser altimetry systems. While laser points accurately sample the ice surface, stereo images allow for the mapping of features, such as crevasses, flow bands, shear margins, moraines, leads, and different types of sea ice. Tracking features in repeat images produces a dense velocity vector field that can either serve as validation for interferometrically derived surface velocities or it constitutes a stand-alone product. A multi-modal, photogrammetric platform consists of one or more high-resolution, commercial color cameras, GPS and inertial navigation system as well as optional laser scanner. Such a system, using a Canon EOS-1DS Mark II camera, was first flown on the Icebridge missions Fall 2009 and Spring 2010, capturing hundreds of thousands of images at a frame rate of about one second. While digital images and videos have been used for quite some time for visual inspection, precise 3D measurements with low cost, commercial cameras require special photogrammetric treatment that only became available recently. Calibrating the multi-camera imaging system and geo-referencing the images are absolute prerequisites for all subsequent applications. Commercial cameras are inherently non-metric, that is, their sensor model is only approximately known. Since these cameras are not as rugged as photogrammetric cameras, the interior orientation also changes, due to temperature and pressure changes and aircraft vibration, resulting in large errors in 3D measurements. It is therefore necessary to calibrate the cameras frequently, at least whenever the system is newly installed. Geo-referencing the images is performed by the Applanix navigation system. Our new method enables a 3D reconstruction of ice sheet surface with high accuracy and unprecedented details, as it is demonstrated by examples from the Antarctic Peninsula, acquired by the IceBridge mission. Repeat digital imaging also provides data for determining surface elevation changes and velocities that are critical parameters for ice sheet models. Although these methods work well, there are known problems with satellite images and the traditional area-based matching, especially over rapidly changing outlet glaciers. To take full advantage of the high resolution, repeat stereo imaging we have developed a new method. The processing starts with the generation of a DEM from geo-referenced stereo images of the first time epoch. The next step is concerned with extracting and matching interest points in object space. Since an interest point moves its spatial position between two time epochs, such points are only radiometrically conjugate but not geometrically. In fact, the geometric displacement of two identical points, together with the time difference, renders velocities. We computed the evolution of the velocity field and surface topography on the floating tongue of the Jakobshavn glacier from historical stereo aerial photographs to illustrate the approach.
Robust and Accurate Image-Based Georeferencing Exploiting Relative Orientation Constraints
NASA Astrophysics Data System (ADS)
Cavegn, S.; Blaser, S.; Nebiker, S.; Haala, N.
2018-05-01
Urban environments with extended areas of poor GNSS coverage as well as indoor spaces that often rely on real-time SLAM algorithms for camera pose estimation require sophisticated georeferencing in order to fulfill our high requirements of a few centimeters for absolute 3D point measurement accuracies. Since we focus on image-based mobile mapping, we extended the structure-from-motion pipeline COLMAP with georeferencing capabilities by integrating exterior orientation parameters from direct sensor orientation or SLAM as well as ground control points into bundle adjustment. Furthermore, we exploit constraints for relative orientation parameters among all cameras in bundle adjustment, which leads to a significant robustness and accuracy increase especially by incorporating highly redundant multi-view image sequences. We evaluated our integrated georeferencing approach on two data sets, one captured outdoors by a vehicle-based multi-stereo mobile mapping system and the other captured indoors by a portable panoramic mobile mapping system. We obtained mean RMSE values for check point residuals between image-based georeferencing and tachymetry of 2 cm in an indoor area, and 3 cm in an urban environment where the measurement distances are a multiple compared to indoors. Moreover, in comparison to a solely image-based procedure, our integrated georeferencing approach showed a consistent accuracy increase by a factor of 2-3 at our outdoor test site. Due to pre-calibrated relative orientation parameters, images of all camera heads were oriented correctly in our challenging indoor environment. By performing self-calibration of relative orientation parameters among respective cameras of our vehicle-based mobile mapping system, remaining inaccuracies from suboptimal test field calibration were successfully compensated.
Strategic options towards an affordable high-performance infrared camera
NASA Astrophysics Data System (ADS)
Oduor, Patrick; Mizuno, Genki; Dutta, Achyut K.; Lewis, Jay; Dhar, Nibir K.
2016-05-01
The promise of infrared (IR) imaging attaining low-cost akin to CMOS sensors success has been hampered by the inability to achieve cost advantages that are necessary for crossover from military and industrial applications into the consumer and mass-scale commercial realm despite well documented advantages. Banpil Photonics is developing affordable IR cameras by adopting new strategies to speed-up the decline of the IR camera cost curve. We present a new short-wave IR (SWIR) camera; 640x512 pixel InGaAs uncooled system that is high sensitivity low noise (<50e-), high dynamic range (100 dB), high-frame rates (> 500 frames per second (FPS)) at full resolution, and low power consumption (< 1 W) in a compact system. This camera paves the way towards mass market adoption by not only demonstrating high-performance IR imaging capability value add demanded by military and industrial application, but also illuminates a path towards justifiable price points essential for consumer facing application industries such as automotive, medical, and security imaging adoption. Among the strategic options presented include new sensor manufacturing technologies that scale favorably towards automation, multi-focal plane array compatible readout electronics, and dense or ultra-small pixel pitch devices.
Low power multi-camera system and algorithms for automated threat detection
NASA Astrophysics Data System (ADS)
Huber, David J.; Khosla, Deepak; Chen, Yang; Van Buer, Darrel J.; Martin, Kevin
2013-05-01
A key to any robust automated surveillance system is continuous, wide field-of-view sensor coverage and high accuracy target detection algorithms. Newer systems typically employ an array of multiple fixed cameras that provide individual data streams, each of which is managed by its own processor. This array can continuously capture the entire field of view, but collecting all the data and back-end detection algorithm consumes additional power and increases the size, weight, and power (SWaP) of the package. This is often unacceptable, as many potential surveillance applications have strict system SWaP requirements. This paper describes a wide field-of-view video system that employs multiple fixed cameras and exhibits low SWaP without compromising the target detection rate. We cycle through the sensors, fetch a fixed number of frames, and process them through a modified target detection algorithm. During this time, the other sensors remain powered-down, which reduces the required hardware and power consumption of the system. We show that the resulting gaps in coverage and irregular frame rate do not affect the detection accuracy of the underlying algorithms. This reduces the power of an N-camera system by up to approximately N-fold compared to the baseline normal operation. This work was applied to Phase 2 of DARPA Cognitive Technology Threat Warning System (CT2WS) program and used during field testing.
Registration of 3D and Multispectral Data for the Study of Cultural Heritage Surfaces
Chane, Camille Simon; Schütze, Rainer; Boochs, Frank; Marzani, Franck S.
2013-01-01
We present a technique for the multi-sensor registration of featureless datasets based on the photogrammetric tracking of the acquisition systems in use. This method is developed for the in situ study of cultural heritage objects and is tested by digitizing a small canvas successively with a 3D digitization system and a multispectral camera while simultaneously tracking the acquisition systems with four cameras and using a cubic target frame with a side length of 500 mm. The achieved tracking accuracy is better than 0.03 mm spatially and 0.150 mrad angularly. This allows us to seamlessly register the 3D acquisitions and to project the multispectral acquisitions on the 3D model. PMID:23322103
NASA Astrophysics Data System (ADS)
Thoeni, K.; Giacomini, A.; Murtagh, R.; Kniest, E.
2014-06-01
This work presents a comparative study between multi-view 3D reconstruction using various digital cameras and a terrestrial laser scanner (TLS). Five different digital cameras were used in order to estimate the limits related to the camera type and to establish the minimum camera requirements to obtain comparable results to the ones of the TLS. The cameras used for this study range from commercial grade to professional grade and included a GoPro Hero 1080 (5 Mp), iPhone 4S (8 Mp), Panasonic Lumix LX5 (9.5 Mp), Panasonic Lumix ZS20 (14.1 Mp) and Canon EOS 7D (18 Mp). The TLS used for this work was a FARO Focus 3D laser scanner with a range accuracy of ±2 mm. The study area is a small rock wall of about 6 m height and 20 m length. The wall is partly smooth with some evident geological features, such as non-persistent joints and sharp edges. Eight control points were placed on the wall and their coordinates were measured by using a total station. These coordinates were then used to georeference all models. A similar number of images was acquired from a distance of between approximately 5 to 10 m, depending on field of view of each camera. The commercial software package PhotoScan was used to process the images, georeference and scale the models, and to generate the dense point clouds. Finally, the open-source package CloudCompare was used to assess the accuracy of the multi-view results. Each point cloud obtained from a specific camera was compared to the point cloud obtained with the TLS. The latter is taken as ground truth. The result is a coloured point cloud for each camera showing the deviation in relation to the TLS data. The main goal of this study is to quantify the quality of the multi-view 3D reconstruction results obtained with various cameras as objectively as possible and to evaluate its applicability to geotechnical problems.
The purpose of the field demonstration program is to gather technically reliable cost and performance information on selected condition assessment technologies under defined field conditions. The selected technologies include zoom camera, electro-scan (FELL-41), and a multi-sens...
Fly-through viewpoint video system for multi-view soccer movie using viewpoint interpolation
NASA Astrophysics Data System (ADS)
Inamoto, Naho; Saito, Hideo
2003-06-01
This paper presents a novel method for virtual view generation that allows viewers to fly through in a real soccer scene. A soccer match is captured by multiple cameras at a stadium and images of arbitrary viewpoints are synthesized by view-interpolation of two real camera images near the given viewpoint. In the proposed method, cameras do not need to be strongly calibrated, but epipolar geometry between the cameras is sufficient for the view-interpolation. Therefore, it can easily be applied to a dynamic event even in a large space, because the efforts for camera calibration can be reduced. A soccer scene is classified into several regions and virtual view images are generated based on the epipolar geometry in each region. Superimposition of the images completes virtual views for the whole soccer scene. An application for fly-through observation of a soccer match is introduced as well as the algorithm of the view-synthesis and experimental results..
NASA Astrophysics Data System (ADS)
Lee, Seungwon; Park, Ilkwon; Kim, Manbae; Byun, Hyeran
2006-10-01
As digital broadcasting technologies have been rapidly progressed, users' expectations for realistic and interactive broadcasting services also have been increased. As one of such services, 3D multi-view broadcasting has received much attention recently. In general, all the view sequences acquired at the server are transmitted to the client. Then, the user can select a part of views or all the views according to display capabilities. However, this kind of system requires high processing power of the server as well as the client, thus posing a difficulty in practical applications. To overcome this problem, a relatively simple method is to transmit only two view-sequences requested by the client in order to deliver a stereoscopic video. In this system, effective communication between the server and the client is one of important aspects. In this paper, we propose an efficient multi-view system that transmits two view-sequences and their depth maps according to user's request. The view selection process is integrated into MPEG-21 DIA (Digital Item Adaptation) so that our system is compatible to MPEG-21 multimedia framework. DIA is generally composed of resource adaptation and descriptor adaptation. It is one of merits that SVA (stereoscopic video adaptation) descriptors defined in DIA standard are used to deliver users' preferences and device capabilities. Furthermore, multi-view descriptions related to multi-view camera and system are newly introduced. The syntax of the descriptions and their elements is represented in XML (eXtensible Markup Language) schema. If the client requests an adapted descriptor (e.g., view numbers) to the server, then the server sends its associated view sequences. Finally, we present a method which can reduce user's visual discomfort that might occur while viewing stereoscopic video. This phenomenon happens when view changes as well as when a stereoscopic image produces excessive disparity caused by a large baseline between two cameras. To solve for the former, IVR (intermediate view reconstruction) is employed for smooth transition between two stereoscopic view sequences. As well, a disparity adjustment scheme is used for the latter. Finally, from the implementation of testbed and the experiments, we can show the valuables and possibilities of our system.
A scalable multi-DLP pico-projector system for virtual reality
NASA Astrophysics Data System (ADS)
Teubl, F.; Kurashima, C.; Cabral, M.; Fels, S.; Lopes, R.; Zuffo, M.
2014-03-01
Virtual Reality (VR) environments can offer immersion, interaction and realistic images to users. A VR system is usually expensive and requires special equipment in a complex setup. One approach is to use Commodity-Off-The-Shelf (COTS) desktop multi-projectors manually or camera based calibrated to reduce the cost of VR systems without significant decrease of the visual experience. Additionally, for non-planar screen shapes, special optics such as lenses and mirrors are required thus increasing costs. We propose a low-cost, scalable, flexible and mobile solution that allows building complex VR systems that projects images onto a variety of arbitrary surfaces such as planar, cylindrical and spherical surfaces. This approach combines three key aspects: 1) clusters of DLP-picoprojectors to provide homogeneous and continuous pixel density upon arbitrary surfaces without additional optics; 2) LED lighting technology for energy efficiency and light control; 3) smaller physical footprint for flexibility purposes. Therefore, the proposed system is scalable in terms of pixel density, energy and physical space. To achieve these goals, we developed a multi-projector software library called FastFusion that calibrates all projectors in a uniform image that is presented to viewers. FastFusion uses a camera to automatically calibrate geometric and photometric correction of projected images from ad-hoc positioned projectors, the only requirement is some few pixels overlapping amongst them. We present results with eight Pico-projectors, with 7 lumens (LED) and DLP 0.17 HVGA Chipset.
NASA Astrophysics Data System (ADS)
McMackin, Lenore; Herman, Matthew A.; Weston, Tyler
2016-02-01
We present the design of a multi-spectral imager built using the architecture of the single-pixel camera. The architecture is enabled by the novel sampling theory of compressive sensing implemented optically using the Texas Instruments DLP™ micro-mirror array. The array not only implements spatial modulation necessary for compressive imaging but also provides unique diffractive spectral features that result in a multi-spectral, high-spatial resolution imager design. The new camera design provides multi-spectral imagery in a wavelength range that extends from the visible to the shortwave infrared without reduction in spatial resolution. In addition to the compressive imaging spectrometer design, we present a diffractive model of the architecture that allows us to predict a variety of detailed functional spatial and spectral design features. We present modeling results, architectural design and experimental results that prove the concept.
Precise visual navigation using multi-stereo vision and landmark matching
NASA Astrophysics Data System (ADS)
Zhu, Zhiwei; Oskiper, Taragay; Samarasekera, Supun; Kumar, Rakesh
2007-04-01
Traditional vision-based navigation system often drifts over time during navigation. In this paper, we propose a set of techniques which greatly reduce the long term drift and also improve its robustness to many failure conditions. In our approach, two pairs of stereo cameras are integrated to form a forward/backward multi-stereo camera system. As a result, the Field-Of-View of the system is extended significantly to capture more natural landmarks from the scene. This helps to increase the pose estimation accuracy as well as reduce the failure situations. Secondly, a global landmark matching technique is used to recognize the previously visited locations during navigation. Using the matched landmarks, a pose correction technique is used to eliminate the accumulated navigation drift. Finally, in order to further improve the robustness of the system, measurements from low-cost Inertial Measurement Unit (IMU) and Global Positioning System (GPS) sensors are integrated with the visual odometry in an extended Kalman Filtering framework. Our system is significantly more accurate and robust than previously published techniques (1~5% localization error) over long-distance navigation both indoors and outdoors. Real world experiments on a human worn system show that the location can be estimated within 1 meter over 500 meters (around 0.1% localization error averagely) without the use of GPS information.
Concept of electro-optical sensor module for sniper detection system
NASA Astrophysics Data System (ADS)
Trzaskawka, Piotr; Dulski, Rafal; Kastek, Mariusz
2010-10-01
The paper presents an initial concept of the electro-optical sensor unit for sniper detection purposes. This unit, comprising of thermal and daylight cameras, can operate as a standalone device but its primary application is a multi-sensor sniper and shot detection system. Being a part of a larger system it should contribute to greater overall system efficiency and lower false alarm rate thanks to data and sensor fusion techniques. Additionally, it is expected to provide some pre-shot detection capabilities. Generally acoustic (or radar) systems used for shot detection offer only "after-the-shot" information and they cannot prevent enemy attack, which in case of a skilled sniper opponent usually means trouble. The passive imaging sensors presented in this paper, together with active systems detecting pointed optics, are capable of detecting specific shooter signatures or at least the presence of suspected objects in the vicinity. The proposed sensor unit use thermal camera as a primary sniper and shot detection tool. The basic camera parameters such as focal plane array size and type, focal length and aperture were chosen on the basis of assumed tactical characteristics of the system (mainly detection range) and current technology level. In order to provide costeffective solution the commercially available daylight camera modules and infrared focal plane arrays were tested, including fast cooled infrared array modules capable of 1000 fps image acquisition rate. The daylight camera operates as a support, providing corresponding visual image, easier to comprehend for a human operator. The initial assumptions concerning sensor operation were verified during laboratory and field test and some example shot recording sequences are presented.
2001-11-29
KENNEDY SPACE CENTER, Fla. -- Fully unwrapped, the Advanced Camera for Surveys, which is suspended by an overhead crane, is checked over by workers. Part of the payload on the Hubble Space Telescope Servicing Mission, STS-109, the ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. Tasks for the mission include replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002
Topview stereo: combining vehicle-mounted wide-angle cameras to a distance sensor array
NASA Astrophysics Data System (ADS)
Houben, Sebastian
2015-03-01
The variety of vehicle-mounted sensors in order to fulfill a growing number of driver assistance tasks has become a substantial factor in automobile manufacturing cost. We present a stereo distance method exploiting the overlapping field of view of a multi-camera fisheye surround view system, as they are used for near-range vehicle surveillance tasks, e.g. in parking maneuvers. Hence, we aim at creating a new input signal from sensors that are already installed. Particular properties of wide-angle cameras (e.g. hanging resolution) demand an adaptation of the image processing pipeline to several problems that do not arise in classical stereo vision performed with cameras carefully designed for this purpose. We introduce the algorithms for rectification, correspondence analysis, and regularization of the disparity image, discuss reasons and avoidance of the shown caveats, and present first results on a prototype topview setup.
Re-identification of persons in multi-camera surveillance under varying viewpoints and illumination
NASA Astrophysics Data System (ADS)
Bouma, Henri; Borsboom, Sander; den Hollander, Richard J. M.; Landsmeer, Sander H.; Worring, Marcel
2012-06-01
The capability to track individuals in CCTV cameras is important for surveillance and forensics alike. However, it is laborious to do over multiple cameras. Therefore, an automated system is desirable. In literature several methods have been proposed, but their robustness against varying viewpoints and illumination is limited. Hence performance in realistic settings is also limited. In this paper, we present a novel method for the automatic re-identification of persons in video from surveillance cameras in a realistic setting. The method is computationally efficient, robust to a wide variety of viewpoints and illumination, simple to implement and it requires no training. We compare the performance of our method to several state-of-the-art methods on a publically available dataset that contains the variety of viewpoints and illumination to allow benchmarking. The results indicate that our method shows good performance and enables a human operator to track persons five times faster.
TENTACLE Multi-Camera Immersive Surveillance System Phase 2
2015-04-16
successful in solving the most challenging video analytics problems and taking the advanced research concepts into working systems for end- users in both...commercial, space and military applications. Notable successes include winning the DARPA Urban Challenge , software autonomy to guide the NASA robots (spirit... challenging urban environments. CMU is developing a scalable and extensible architecture, improving search/pursuit/tracking capabilities, and addressing
A multi-channel coronal spectrophotometer.
NASA Technical Reports Server (NTRS)
Landman, D. A.; Orrall, F. Q.; Zane, R.
1973-01-01
We describe a new multi-channel coronal spectrophotometer system, presently being installed at Mees Solar Observatory, Mount Haleakala, Maui. The apparatus is designed to record and interpret intensities from many sections of the visible and near-visible spectral regions simultaneously, with relatively high spatial and temporal resolution. The detector, a thermoelectrically cooled silicon vidicon camera tube, has its central target area divided into a rectangular array of about 100,000 pixels and is read out in a slow-scan (about 2 sec/frame) mode. Instrument functioning is entirely under PDP 11/45 computer control, and interfacing is via the CAMAC system.
Compact streak camera for the shock study of solids by using the high-pressure gas gun
NASA Astrophysics Data System (ADS)
Nagayama, Kunihito; Mori, Yasuhito
1993-01-01
For the precise observation of high-speed impact phenomena, a compact high-speed streak camera recording system has been developed. The system consists of a high-pressure gas gun, a streak camera, and a long-pulse dye laser. The gas gun installed in our laboratory has a muzzle of 40 mm in diameter, and a launch tube of 2 m long. Projectile velocity is measured by the laser beam cut method. The gun is capable of accelerating a 27 g projectile up to 500 m/s, if helium gas is used as a driver. The system has been designed on the principal idea that the precise optical measurement methods developed in other areas of research can be applied to the gun study. The streak camera is 300 mm in diameter, with a rectangular rotating mirror which is driven by an air turbine spindle. The attainable streak velocity is 3 mm/microsecond(s) . The size of the camera is rather small aiming at the portability and economy. Therefore, the streak velocity is relatively slower than the fast cameras, but it is possible to use low-sensitivity but high-resolution film as a recording medium. We have also constructed a pulsed dye laser of 25 - 30 microsecond(s) in duration. The laser can be used as a light source of observation. The advantage for the use of the laser will be multi-fold, i.e., good directivity, almost single frequency, and so on. The feasibility of the system has been demonstrated by performing several experiments.
Graphic overlays in high-precision teleoperation: Current and future work at JPL
NASA Technical Reports Server (NTRS)
Diner, Daniel B.; Venema, Steven C.
1989-01-01
In space teleoperation additional problems arise, including signal transmission time delays. These can greatly reduce operator performance. Recent advances in graphics open new possibilities for addressing these and other problems. Currently a multi-camera system with normal 3-D TV and video graphics capabilities is being developed. Trained and untrained operators will be tested for high precision performance using two force reflecting hand controllers and a voice recognition system to control two robot arms and up to 5 movable stereo or non-stereo TV cameras. A number of new techniques of integrating TV and video graphics displays to improve operator training and performance in teleoperation and supervised automation are evaluated.
NASA Astrophysics Data System (ADS)
Alves, J.; Saraiva, A. C. V.; Campos, L. Z. D. S.; Pinto, O., Jr.; Antunes, L.
2014-12-01
This work presents a method for the evaluation of location accuracy of all Lightning Location System (LLS) in operation in southeastern Brazil, using natural cloud-to-ground (CG) lightning flashes. This can be done through a multiple high-speed cameras network (RAMMER network) installed in the Paraiba Valley region - SP - Brazil. The RAMMER network (Automated Multi-camera Network for Monitoring and Study of Lightning) is composed by four high-speed cameras operating at 2,500 frames per second. Three stationary black-and-white (B&W) cameras were situated in the cities of São José dos Campos and Caçapava. A fourth color camera was mobile (installed in a car), but operated in a fixed location during the observation period, within the city of São José dos Campos. The average distance among cameras was 13 kilometers. Each RAMMER sensor position was determined so that the network can observe the same lightning flash from different angles and all recorded videos were GPS (Global Position System) time stamped, allowing comparisons of events between cameras and the LLS. The RAMMER sensor is basically composed by a computer, a Phantom high-speed camera version 9.1 and a GPS unit. The lightning cases analyzed in the present work were observed by at least two cameras, their position was visually triangulated and the results compared with BrasilDAT network, during the summer seasons of 2011/2012 and 2012/2013. The visual triangulation method is presented in details. The calibration procedure showed an accuracy of 9 meters between the accurate GPS position of the object triangulated and the result from the visual triangulation method. Lightning return stroke positions, estimated with the visual triangulation method, were compared with LLS locations. Differences between solutions were not greater than 1.8 km.
NASA Astrophysics Data System (ADS)
Boxx, I.; Carter, C. D.; Meier, W.
2014-08-01
Tomographic particle image velocimetry (tomographic-PIV) is a recently developed measurement technique used to acquire volumetric velocity field data in liquid and gaseous flows. The technique relies on line-of-sight reconstruction of the rays between a 3D particle distribution and a multi-camera imaging system. In a turbulent flame, however, index-of-refraction variations resulting from local heat-release may inhibit reconstruction and thereby render the technique infeasible. The objective of this study was to test the efficacy of tomographic-PIV in a turbulent flame. An additional goal was to determine the feasibility of acquiring usable tomographic-PIV measurements in a turbulent flame at multi-kHz acquisition rates with current-generation laser and camera technology. To this end, a setup consisting of four complementary metal oxide semiconductor cameras and a dual-cavity Nd:YAG laser was implemented to test the technique in a lifted turbulent jet flame. While the cameras were capable of kHz-rate image acquisition, the laser operated at a pulse repetition rate of only 10 Hz. However, use of this laser allowed exploration of the required pulse energy and thus power for a kHz-rate system. The imaged region was 29 × 28 × 2.7 mm in size. The tomographic reconstruction of the 3D particle distributions was accomplished using the multiplicative algebraic reconstruction technique. The results indicate that volumetric velocimetry via tomographic-PIV is feasible with pulse energies of 25 mJ, which is within the capability of current-generation kHz-rate diode-pumped solid-state lasers.
NASA Astrophysics Data System (ADS)
Ikeda, Sei; Sato, Tomokazu; Kanbara, Masayuki; Yokoya, Naokazu
2004-05-01
Technology that enables users to experience a remote site virtually is called telepresence. A telepresence system using real environment images is expected to be used in the field of entertainment, medicine, education and so on. This paper describes a novel telepresence system which enables users to walk through a photorealistic virtualized environment by actual walking. To realize such a system, a wide-angle high-resolution movie is projected on an immersive multi-screen display to present users the virtualized environments and a treadmill is controlled according to detected user's locomotion. In this study, we use an omnidirectional multi-camera system to acquire images real outdoor scene. The proposed system provides users with rich sense of walking in a remote site.
Detailed analysis of an optimized FPP-based 3D imaging system
NASA Astrophysics Data System (ADS)
Tran, Dat; Thai, Anh; Duong, Kiet; Nguyen, Thanh; Nehmetallah, Georges
2016-05-01
In this paper, we present detail analysis and a step-by-step implementation of an optimized fringe projection profilometry (FPP) based 3D shape measurement system. First, we propose a multi-frequency and multi-phase shifting sinusoidal fringe pattern reconstruction approach to increase accuracy and sensitivity of the system. Second, phase error compensation caused by the nonlinear transfer function of the projector and camera is performed through polynomial approximation. Third, phase unwrapping is performed using spatial and temporal techniques and the tradeoff between processing speed and high accuracy is discussed in details. Fourth, generalized camera and system calibration are developed for phase to real world coordinate transformation. The calibration coefficients are estimated accurately using a reference plane and several gauge blocks with precisely known heights and by employing a nonlinear least square fitting method. Fifth, a texture will be attached to the height profile by registering a 2D real photo to the 3D height map. The last step is to perform 3D image fusion and registration using an iterative closest point (ICP) algorithm for a full field of view reconstruction. The system is experimentally constructed using compact, portable, and low cost off-the-shelf components. A MATLAB® based GUI is developed to control and synchronize the whole system.
Software defined multi-spectral imaging for Arctic sensor networks
NASA Astrophysics Data System (ADS)
Siewert, Sam; Angoth, Vivek; Krishnamurthy, Ramnarayan; Mani, Karthikeyan; Mock, Kenrick; Singh, Surjith B.; Srivistava, Saurav; Wagner, Chris; Claus, Ryan; Vis, Matthew Demi
2016-05-01
Availability of off-the-shelf infrared sensors combined with high definition visible cameras has made possible the construction of a Software Defined Multi-Spectral Imager (SDMSI) combining long-wave, near-infrared and visible imaging. The SDMSI requires a real-time embedded processor to fuse images and to create real-time depth maps for opportunistic uplink in sensor networks. Researchers at Embry Riddle Aeronautical University working with University of Alaska Anchorage at the Arctic Domain Awareness Center and the University of Colorado Boulder have built several versions of a low-cost drop-in-place SDMSI to test alternatives for power efficient image fusion. The SDMSI is intended for use in field applications including marine security, search and rescue operations and environmental surveys in the Arctic region. Based on Arctic marine sensor network mission goals, the team has designed the SDMSI to include features to rank images based on saliency and to provide on camera fusion and depth mapping. A major challenge has been the design of the camera computing system to operate within a 10 to 20 Watt power budget. This paper presents a power analysis of three options: 1) multi-core, 2) field programmable gate array with multi-core, and 3) graphics processing units with multi-core. For each test, power consumed for common fusion workloads has been measured at a range of frame rates and resolutions. Detailed analyses from our power efficiency comparison for workloads specific to stereo depth mapping and sensor fusion are summarized. Preliminary mission feasibility results from testing with off-the-shelf long-wave infrared and visible cameras in Alaska and Arizona are also summarized to demonstrate the value of the SDMSI for applications such as ice tracking, ocean color, soil moisture, animal and marine vessel detection and tracking. The goal is to select the most power efficient solution for the SDMSI for use on UAVs (Unoccupied Aerial Vehicles) and other drop-in-place installations in the Arctic. The prototype selected will be field tested in Alaska in the summer of 2016.
Face recognition system for set-top box-based intelligent TV.
Lee, Won Oh; Kim, Yeong Gon; Hong, Hyung Gil; Park, Kang Ryoung
2014-11-18
Despite the prevalence of smart TVs, many consumers continue to use conventional TVs with supplementary set-top boxes (STBs) because of the high cost of smart TVs. However, because the processing power of a STB is quite low, the smart TV functionalities that can be implemented in a STB are very limited. Because of this, negligible research has been conducted regarding face recognition for conventional TVs with supplementary STBs, even though many such studies have been conducted with smart TVs. In terms of camera sensors, previous face recognition systems have used high-resolution cameras, cameras with high magnification zoom lenses, or camera systems with panning and tilting devices that can be used for face recognition from various positions. However, these cameras and devices cannot be used in intelligent TV environments because of limitations related to size and cost, and only small, low cost web-cameras can be used. The resulting face recognition performance is degraded because of the limited resolution and quality levels of the images. Therefore, we propose a new face recognition system for intelligent TVs in order to overcome the limitations associated with low resource set-top box and low cost web-cameras. We implement the face recognition system using a software algorithm that does not require special devices or cameras. Our research has the following four novelties: first, the candidate regions in a viewer's face are detected in an image captured by a camera connected to the STB via low processing background subtraction and face color filtering; second, the detected candidate regions of face are transmitted to a server that has high processing power in order to detect face regions accurately; third, in-plane rotations of the face regions are compensated based on similarities between the left and right half sub-regions of the face regions; fourth, various poses of the viewer's face region are identified using five templates obtained during the initial user registration stage and multi-level local binary pattern matching. Experimental results indicate that the recall; precision; and genuine acceptance rate were about 95.7%; 96.2%; and 90.2%, respectively.
NASA Astrophysics Data System (ADS)
Chen, C.; Zou, X.; Tian, M.; Li, J.; Wu, W.; Song, Y.; Dai, W.; Yang, B.
2017-11-01
In order to solve the automation of 3D indoor mapping task, a low cost multi-sensor robot laser scanning system is proposed in this paper. The multiple-sensor robot laser scanning system includes a panorama camera, a laser scanner, and an inertial measurement unit and etc., which are calibrated and synchronized together to achieve simultaneously collection of 3D indoor data. Experiments are undertaken in a typical indoor scene and the data generated by the proposed system are compared with ground truth data collected by a TLS scanner showing an accuracy of 99.2% below 0.25 meter, which explains the applicability and precision of the system in indoor mapping applications.
Airborne imaging for heritage documentation using the Fotokite tethered flying camera
NASA Astrophysics Data System (ADS)
Verhoeven, Geert; Lupashin, Sergei; Briese, Christian; Doneus, Michael
2014-05-01
Since the beginning of aerial photography, researchers used all kinds of devices (from pigeons, kites, poles, and balloons to rockets) to take still cameras aloft and remotely gather aerial imagery. To date, many of these unmanned devices are still used for what has been referred to as Low-Altitude Aerial Photography or LAAP. In addition to these more traditional camera platforms, radio-controlled (multi-)copter platforms have recently added a new aspect to LAAP. Although model airplanes have been around for several decades, the decreasing cost, increasing functionality and stability of ready-to-fly multi-copter systems has proliferated their use among non-hobbyists. As such, they became a very popular tool for aerial imaging. The overwhelming amount of currently available brands and types (heli-, dual-, tri-, quad-, hexa-, octo-, dodeca-, deca-hexa and deca-octocopters), together with the wide variety of navigation options (e.g. altitude and position hold, waypoint flight) and camera mounts indicate that these platforms are here to stay for some time. Given the multitude of still camera types and the image quality they are currently capable of, endless combinations of low- and high-cost LAAP solutions are available. In addition, LAAP allows for the exploitation of new imaging techniques, as it is often only a matter of lifting the appropriate device (e.g. video cameras, thermal frame imagers, hyperspectral line sensors). Archaeologists were among the first to adopt this technology, as it provided them with a means to easily acquire essential data from a unique point of view, whether for simple illustration purposes of standing historic structures or to compute three-dimensional (3D) models and orthophotographs from excavation areas. However, even very cheap multi-copters models require certain skills to pilot them safely. Additionally, malfunction or overconfidence might lift these devices to altitudes where they can interfere with manned aircrafts. As such, the safe operation of these devices is still an issue, certainly when flying on locations which can be crowded (such as students on excavations or tourists walking around historic places). As the future of UAS regulation remains unclear, this talk presents an alternative approach to aerial imaging: the Fotokite. Developed at the ETH Zürich, the Fotokite is a tethered flying camera that is essentially a multi-copter connected to the ground with a taut tether to achieve controlled flight. Crucially, it relies solely on onboard IMU (Inertial Measurement Unit) measurements to fly, launches in seconds, and is classified as not a UAS (Unmanned Aerial System), e.g. in the latest FAA (Federal Aviation Administration) UAS proposal. As a result it may be used for imaging cultural heritage in a variety of environments and settings with minimal training by non-experienced pilots. Furthermore, it is subject to less extensive certification, regulation and import/export restrictions, making it a viable solution for use at a greater range of sites than traditional methods. Unlike a balloon or a kite it is not subject to particular weather conditions and, thanks to active stabilization, is capable of a variety of intelligent flight modes. Finally, it is compact and lightweight, making it easy to transport and deploy, and its lack of reliance on GNSS (Global Navigation Satellite System) makes it possible to use in urban, overbuilt areas. After outlining its operating principles, the talk will present some archaeological case studies in which the Fotokite was used, hereby assessing its capabilities compared to the conventional UAS's on the market.
NASA Astrophysics Data System (ADS)
Maloney, P. R.; Czakon, N. G.; Day, P. K.; Duan, R.; Gao, J.; Glenn, J.; Golwala, S.; Hollister, M.; LeDuc, H. G.; Mazin, B.; Noroozian, O.; Nguyen, H. T.; Sayers, J.; Schlaerth, J.; Vaillancourt, J. E.; Vayonakis, A.; Wilson, P.; Zmuidzinas, J.
2009-12-01
The MKID Camera project is a collaborative effort of Caltech, JPL, the University of Colorado, and UC Santa Barbara to develop a large-format, multi-color millimeter and submillimeter-wavelength camera for astronomy using microwave kinetic inductance detectors (MKIDs). These are superconducting, micro-resonators fabricated from thin aluminum and niobium films. We couple the MKIDs to multi-slot antennas and measure the change in surface impedance produced by photon-induced breaking of Cooper pairs. The readout is almost entirely at room temperature and can be highly multiplexed; in principle hundreds or even thousands of resonators could be read out on a single feedline. The camera will have 576 spatial pixels that image simultaneously in four bands at 750, 850, 1100 and 1300 microns. It is scheduled for deployment at the Caltech Submillimeter Observatory in the summer of 2010. We present an overview of the camera design and readout and describe the current status of testing and fabrication.
Demonstration of in-vivo Multi-Probe Tracker Based on a Si/CdTe Semiconductor Compton Camera
NASA Astrophysics Data System (ADS)
Takeda, Shin'ichiro; Odaka, Hirokazu; Ishikawa, Shin-nosuke; Watanabe, Shin; Aono, Hiroyuki; Takahashi, Tadayuki; Kanayama, Yousuke; Hiromura, Makoto; Enomoto, Shuichi
2012-02-01
By using a prototype Compton camera consisting of silicon (Si) and cadmium telluride (CdTe) semiconductor detectors, originally developed for the ASTRO-H satellite mission, an experiment involving imaging multiple radiopharmaceuticals injected into a living mouse was conducted to study its feasibility for medical imaging. The accumulation of both iodinated (131I) methylnorcholestenol and 85Sr into the mouse's organs was simultaneously imaged by the prototype. This result implies that the Compton camera is expected to become a multi-probe tracker available in nuclear medicine and small animal imaging.
New developments in flash radiography
NASA Astrophysics Data System (ADS)
Mattsson, Arne
2007-01-01
The paper will review some of the latest developments in flash radiography. A series of multi anode tubes has been developed. These are tubes with several x-ray sources within the same vacuum enclosure. The x-ray sources are closely spaced, to come as close as possible to a single source. The x-ray sources are sequentially pulsed, at times that can be independently chosen. Tubes for voltages in the range 150 - 500 kV, with up to eight x-ray sources, will be described. Combining a multi anode tube with an intensified CCD camera, will make it possible to generate short "x-ray movies". A new flash x-ray control system has been developed. The system is operated from a PC or Laptop. All parameters of a multi channel flash x-ray system can be remotely set and monitored. The system will automatically store important operation parameters.
Near-infrared high-resolution real-time omnidirectional imaging platform for drone detection
NASA Astrophysics Data System (ADS)
Popovic, Vladan; Ott, Beat; Wellig, Peter; Leblebici, Yusuf
2016-10-01
Recent technological advancements in hardware systems have made higher quality cameras. State of the art panoramic systems use them to produce videos with a resolution of 9000 x 2400 pixels at a rate of 30 frames per second (fps).1 Many modern applications use object tracking to determine the speed and the path taken by each object moving through a scene. The detection requires detailed pixel analysis between two frames. In fields like surveillance systems or crowd analysis, this must be achieved in real time.2 In this paper, we focus on the system-level design of multi-camera sensor acquiring near-infrared (NIR) spectrum and its ability to detect mini-UAVs in a representative rural Swiss environment. The presented results show the UAV detection from the trial that we conducted during a field trial in August 2015.
The Advanced Gamma-ray Imaging System (AGIS): Camera Electronics Designs
NASA Astrophysics Data System (ADS)
Tajima, H.; Buckley, J.; Byrum, K.; Drake, G.; Falcone, A.; Funk, S.; Holder, J.; Horan, D.; Krawczynski, H.; Ong, R.; Swordy, S.; Wagner, R.; Williams, D.
2008-04-01
AGIS, a next generation of atmospheric Cherenkov telescope arrays, aims to achieve a sensitivity level of a milliCrab for gamma-ray observations in the energy band of 40 GeV to 100 TeV. Such improvement requires cost reduction of individual components with high reliability in order to equip the order of 100 telescopes necessary to achieve the sensitivity goal. We are exploring several design concepts to reduce the cost of camera electronics while improving their performance. These design concepts include systems based on multi-channel waveform sampling ASIC optimized for AGIS, a system based on IIT (image intensifier tube) for large channel (order of 1 million channels) readout as well as a multiplexed FADC system based on the current VERITAS readout design. Here we present trade-off in the studies of these design concepts.
The Advanced Gamma-ray Imaging System (AGIS): Camera Electronics Designs
NASA Astrophysics Data System (ADS)
Tajima, Hiroyasu; Buckley, J.; Byrum, K.; Drake, G.; Falcone, A.; Funk, S.; Holder, J.; Horan, D.; Krawczynski, H.; Ong, R.; Swordy, S.; Wagner, R.; Wakely, S.; Williams, D.; Camera Electronics Working Group; AGIS Collaboration
2008-03-01
AGIS, a next generation of atmospheric Cherenkov telescope arrays, aims to achieve a sensitivity level of a milliCrab for gamma-ray observations in in the energy band of 40 GeV to 100 TeV. Such improvement requires cost reduction of individual components with high reliability in order to equip the order of 100 telescopes necessary to achieve the sensitivity goal. We are exploring several design concepts to reduce the cost of camera electronics while improving their performance. These design concepts include systems based on multi-channel waveform sampling ASIC optimized for AGIS, a system based on IIT (image intensifier tube) for large channel (order of 1 million channels) readout as well as a multiplexed FADC system based on the current VERITAS readout design. Here we present trade-off studies of these design concepts.
2001-11-27
KENNEDY SPACE CENTER, Fla. -- In the Vertical Processing Facility, members of the STS-109 crew look over the Solar Array 3 panels that will be replacing Solar Array 2 panels on the Hubble Space Telescope (HST). Trainers, at left, point to the panels while Mission Specialist Nancy Currie (second from right) and Commander Scott Altman (far right) look on. Other crew members are Pilot Duane Carey, Payload Commander John Grunsfeld and Mission Specialists James Newman, Richard Linnehan and Michael Massimino. The other goals of the mission are replacing the Power Control Unit, removing the Faint Object Camera and installing the Advanced Camera for Surveys, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002
Real-time Enhancement, Registration, and Fusion for a Multi-Sensor Enhanced Vision System
NASA Technical Reports Server (NTRS)
Hines, Glenn D.; Rahman, Zia-ur; Jobson, Daniel J.; Woodell, Glenn A.
2006-01-01
Over the last few years NASA Langley Research Center (LaRC) has been developing an Enhanced Vision System (EVS) to aid pilots while flying in poor visibility conditions. The EVS captures imagery using two infrared video cameras. The cameras are placed in an enclosure that is mounted and flown forward-looking underneath the NASA LaRC ARIES 757 aircraft. The data streams from the cameras are processed in real-time and displayed on monitors on-board the aircraft. With proper processing the camera system can provide better-than- human-observed imagery particularly during poor visibility conditions. However, to obtain this goal requires several different stages of processing including enhancement, registration, and fusion, and specialized processing hardware for real-time performance. We are using a real-time implementation of the Retinex algorithm for image enhancement, affine transformations for registration, and weighted sums to perform fusion. All of the algorithms are executed on a single TI DM642 digital signal processor (DSP) clocked at 720 MHz. The image processing components were added to the EVS system, tested, and demonstrated during flight tests in August and September of 2005. In this paper we briefly discuss the EVS image processing hardware and algorithms. We then discuss implementation issues and show examples of the results obtained during flight tests. Keywords: enhanced vision system, image enhancement, retinex, digital signal processing, sensor fusion
NASA Astrophysics Data System (ADS)
Chen, Chung-Hao; Yao, Yi; Chang, Hong; Koschan, Andreas; Abidi, Mongi
2013-06-01
Due to increasing security concerns, a complete security system should consist of two major components, a computer-based face-recognition system and a real-time automated video surveillance system. A computerbased face-recognition system can be used in gate access control for identity authentication. In recent studies, multispectral imaging and fusion of multispectral narrow-band images in the visible spectrum have been employed and proven to enhance the recognition performance over conventional broad-band images, especially when the illumination changes. Thus, we present an automated method that specifies the optimal spectral ranges under the given illumination. Experimental results verify the consistent performance of our algorithm via the observation that an identical set of spectral band images is selected under all tested conditions. Our discovery can be practically used for a new customized sensor design associated with given illuminations for an improved face recognition performance over conventional broad-band images. In addition, once a person is authorized to enter a restricted area, we still need to continuously monitor his/her activities for the sake of security. Because pantilt-zoom (PTZ) cameras are capable of covering a panoramic area and maintaining high resolution imagery for real-time behavior understanding, researches in automated surveillance systems with multiple PTZ cameras have become increasingly important. Most existing algorithms require the prior knowledge of intrinsic parameters of the PTZ camera to infer the relative positioning and orientation among multiple PTZ cameras. To overcome this limitation, we propose a novel mapping algorithm that derives the relative positioning and orientation between two PTZ cameras based on a unified polynomial model. This reduces the dependence on the knowledge of intrinsic parameters of PTZ camera and relative positions. Experimental results demonstrate that our proposed algorithm presents substantially reduced computational complexity and improved flexibility at the cost of slightly decreased pixel accuracy as compared to Chen and Wang's method [18].
High-precision real-time 3D shape measurement based on a quad-camera system
NASA Astrophysics Data System (ADS)
Tao, Tianyang; Chen, Qian; Feng, Shijie; Hu, Yan; Zhang, Minliang; Zuo, Chao
2018-01-01
Phase-shifting profilometry (PSP) based 3D shape measurement is well established in various applications due to its high accuracy, simple implementation, and robustness to environmental illumination and surface texture. In PSP, higher depth resolution generally requires higher fringe density of projected patterns which, in turn, lead to severe phase ambiguities that must be solved with additional information from phase coding and/or geometric constraints. However, in order to guarantee the reliability of phase unwrapping, available techniques are usually accompanied by increased number of patterns, reduced amplitude of fringe, and complicated post-processing algorithms. In this work, we demonstrate that by using a quad-camera multi-view fringe projection system and carefully arranging the relative spatial positions between the cameras and the projector, it becomes possible to completely eliminate the phase ambiguities in conventional three-step PSP patterns with high-fringe-density without projecting any additional patterns or embedding any auxiliary signals. Benefiting from the position-optimized quad-camera system, stereo phase unwrapping can be efficiently and reliably performed by flexible phase consistency checks. Besides, redundant information of multiple phase consistency checks is fully used through a weighted phase difference scheme to further enhance the reliability of phase unwrapping. This paper explains the 3D measurement principle and the basic design of quad-camera system, and finally demonstrates that in a large measurement volume of 200 mm × 200 mm × 400 mm, the resultant dynamic 3D sensing system can realize real-time 3D reconstruction at 60 frames per second with a depth precision of 50 μm.
Multi-Task Learning with Low Rank Attribute Embedding for Multi-Camera Person Re-Identification.
Su, Chi; Yang, Fan; Zhang, Shiliang; Tian, Qi; Davis, Larry Steven; Gao, Wen
2018-05-01
We propose Multi-Task Learning with Low Rank Attribute Embedding (MTL-LORAE) to address the problem of person re-identification on multi-cameras. Re-identifications on different cameras are considered as related tasks, which allows the shared information among different tasks to be explored to improve the re-identification accuracy. The MTL-LORAE framework integrates low-level features with mid-level attributes as the descriptions for persons. To improve the accuracy of such description, we introduce the low-rank attribute embedding, which maps original binary attributes into a continuous space utilizing the correlative relationship between each pair of attributes. In this way, inaccurate attributes are rectified and missing attributes are recovered. The resulting objective function is constructed with an attribute embedding error and a quadratic loss concerning class labels. It is solved by an alternating optimization strategy. The proposed MTL-LORAE is tested on four datasets and is validated to outperform the existing methods with significant margins.
Research of flaw image collecting and processing technology based on multi-baseline stereo imaging
NASA Astrophysics Data System (ADS)
Yao, Yong; Zhao, Jiguang; Pang, Xiaoyan
2008-03-01
Aiming at the practical situations such as accurate optimal design, complex algorithms and precise technical demands of gun bore flaw image collecting, the design frame of a 3-D image collecting and processing system based on multi-baseline stereo imaging was presented in this paper. This system mainly including computer, electrical control box, stepping motor and CCD camera and it can realize function of image collection, stereo matching, 3-D information reconstruction and after-treatments etc. Proved by theoretical analysis and experiment results, images collected by this system were precise and it can slake efficiently the uncertainty problem produced by universally veins or repeated veins. In the same time, this system has faster measure speed and upper measure precision.
A system for tracking and recognizing pedestrian faces using a network of loosely coupled cameras
NASA Astrophysics Data System (ADS)
Gagnon, L.; Laliberté, F.; Foucher, S.; Branzan Albu, A.; Laurendeau, D.
2006-05-01
A face recognition module has been developed for an intelligent multi-camera video surveillance system. The module can recognize a pedestrian face in terms of six basic emotions and the neutral state. Face and facial features detection (eyes, nasal root, nose and mouth) are first performed using cascades of boosted classifiers. These features are used to normalize the pose and dimension of the face image. Gabor filters are then sampled on a regular grid covering the face image to build a facial feature vector that feeds a nearest neighbor classifier with a cosine distance similarity measure for facial expression interpretation and face model construction. A graphical user interface allows the user to adjust the module parameters.
Development, characterization, and modeling of a tunable filter camera
NASA Astrophysics Data System (ADS)
Sartor, Mark Alan
1999-10-01
This paper describes the development, characterization, and modeling of a Tunable Filter Camera (TFC). The TFC is a new multispectral instrument with electronically tuned spectral filtering and low-light-level sensitivity. It represents a hybrid between hyperspectral and multispectral imaging spectrometers that incorporates advantages from each, addressing issues such as complexity, cost, lack of sensitivity, and adaptability. These capabilities allow the TFC to be applied to low- altitude video surveillance for real-time spectral and spatial target detection and image exploitation. Described herein are the theory and principles of operation for the TFC, which includes a liquid crystal tunable filter, an intensified CCD, and a custom apochromatic lens. The results of proof-of-concept testing, and characterization of two prototype cameras are included, along with a summary of the design analyses for the development of a multiple-channel system. A significant result of this effort was the creation of a system-level model, which was used to facilitate development and predict performance. It includes models for the liquid crystal tunable filter and intensified CCD. Such modeling was necessary in the design of the system and is useful for evaluation of the system in remote-sensing applications. Also presented are characterization data from component testing, which included quantitative results for linearity, signal to noise ratio (SNR), linearity, and radiometric response. These data were used to help refine and validate the model. For a pre-defined source, the spatial and spectral response, and the noise of the camera, system can now be predicted. The innovation that sets this development apart is the fact that this instrument has been designed for integrated, multi-channel operation for the express purpose of real-time detection/identification in low- light-level conditions. Many of the requirements for the TFC were derived from this mission. In order to provide background for the design requirements for the TFC development, the mission and principles of operation behind the multi-channel system will be reviewed. Given the combination of the flexibility, simplicity, and sensitivity, the TFC and its multiple-channel extension can play a significant role in the next generation of remote-sensing instruments.
Airborne net-centric multi-INT sensor control, display, fusion, and exploitation systems
NASA Astrophysics Data System (ADS)
Linne von Berg, Dale C.; Lee, John N.; Kruer, Melvin R.; Duncan, Michael D.; Olchowski, Fred M.; Allman, Eric; Howard, Grant
2004-08-01
The NRL Optical Sciences Division has initiated a multi-year effort to develop and demonstrate an airborne net-centric suite of multi-intelligence (multi-INT) sensors and exploitation systems for real-time target detection and targeting product dissemination. The goal of this Net-centric Multi-Intelligence Fusion Targeting Initiative (NCMIFTI) is to develop an airborne real-time intelligence gathering and targeting system that can be used to detect concealed, camouflaged, and mobile targets. The multi-INT sensor suite will include high-resolution visible/infrared (EO/IR) dual-band cameras, hyperspectral imaging (HSI) sensors in the visible-to-near infrared, short-wave and long-wave infrared (VNIR/SWIR/LWIR) bands, Synthetic Aperture Radar (SAR), electronics intelligence sensors (ELINT), and off-board networked sensors. Other sensors are also being considered for inclusion in the suite to address unique target detection needs. Integrating a suite of multi-INT sensors on a single platform should optimize real-time fusion of the on-board sensor streams, thereby improving the detection probability and reducing the false alarms that occur in reconnaissance systems that use single-sensor types on separate platforms, or that use independent target detection algorithms on multiple sensors. In addition to the integration and fusion of the multi-INT sensors, the effort is establishing an open-systems net-centric architecture that will provide a modular "plug and play" capability for additional sensors and system components and provide distributed connectivity to multiple sites for remote system control and exploitation.
An integrated compact airborne multispectral imaging system using embedded computer
NASA Astrophysics Data System (ADS)
Zhang, Yuedong; Wang, Li; Zhang, Xuguo
2015-08-01
An integrated compact airborne multispectral imaging system using embedded computer based control system was developed for small aircraft multispectral imaging application. The multispectral imaging system integrates CMOS camera, filter wheel with eight filters, two-axis stabilized platform, miniature POS (position and orientation system) and embedded computer. The embedded computer has excellent universality and expansibility, and has advantages in volume and weight for airborne platform, so it can meet the requirements of control system of the integrated airborne multispectral imaging system. The embedded computer controls the camera parameters setting, filter wheel and stabilized platform working, image and POS data acquisition, and stores the image and data. The airborne multispectral imaging system can connect peripheral device use the ports of the embedded computer, so the system operation and the stored image data management are easy. This airborne multispectral imaging system has advantages of small volume, multi-function, and good expansibility. The imaging experiment results show that this system has potential for multispectral remote sensing in applications such as resource investigation and environmental monitoring.
Multi-band infrared camera systems
NASA Astrophysics Data System (ADS)
Davis, Tim; Lang, Frank; Sinneger, Joe; Stabile, Paul; Tower, John
1994-12-01
The program resulted in an IR camera system that utilizes a unique MOS addressable focal plane array (FPA) with full TV resolution, electronic control capability, and windowing capability. Two systems were delivered, each with two different camera heads: a Stirling-cooled 3-5 micron band head and a liquid nitrogen-cooled, filter-wheel-based, 1.5-5 micron band head. Signal processing features include averaging up to 16 frames, flexible compensation modes, gain and offset control, and real-time dither. The primary digital interface is a Hewlett-Packard standard GPID (IEEE-488) port that is used to upload and download data. The FPA employs an X-Y addressed PtSi photodiode array, CMOS horizontal and vertical scan registers, horizontal signal line (HSL) buffers followed by a high-gain preamplifier and a depletion NMOS output amplifier. The 640 x 480 MOS X-Y addressed FPA has a high degree of flexibility in operational modes. By changing the digital data pattern applied to the vertical scan register, the FPA can be operated in either an interlaced or noninterlaced format. The thermal sensitivity performance of the second system's Stirling-cooled head was the best of the systems produced.
Fusion-based multi-target tracking and localization for intelligent surveillance systems
NASA Astrophysics Data System (ADS)
Rababaah, Haroun; Shirkhodaie, Amir
2008-04-01
In this paper, we have presented two approaches addressing visual target tracking and localization in complex urban environment. The two techniques presented in this paper are: fusion-based multi-target visual tracking, and multi-target localization via camera calibration. For multi-target tracking, the data fusion concepts of hypothesis generation/evaluation/selection, target-to-target registration, and association are employed. An association matrix is implemented using RGB histograms for associated tracking of multi-targets of interests. Motion segmentation of targets of interest (TOI) from the background was achieved by a Gaussian Mixture Model. Foreground segmentation, on other hand, was achieved by the Connected Components Analysis (CCA) technique. The tracking of individual targets was estimated by fusing two sources of information, the centroid with the spatial gating, and the RGB histogram association matrix. The localization problem is addressed through an effective camera calibration technique using edge modeling for grid mapping (EMGM). A two-stage image pixel to world coordinates mapping technique is introduced that performs coarse and fine location estimation of moving TOIs. In coarse estimation, an approximate neighborhood of the target position is estimated based on nearest 4-neighbor method, and in fine estimation, we use Euclidean interpolation to localize the position within the estimated four neighbors. Both techniques were tested and shown reliable results for tracking and localization of Targets of interests in complex urban environment.
Retinal axial focusing and multi-layer imaging with a liquid crystal adaptive optics camera
NASA Astrophysics Data System (ADS)
Liu, Rui-Xue; Zheng, Xian-Liang; Li, Da-Yu; Xia, Ming-Liang; Hu, Li-Fa; Cao, Zhao-Liang; Mu, Quan-Quan; Xuan, Li
2014-09-01
With the help of adaptive optics (AO) technology, cellular level imaging of living human retina can be achieved. Aiming to reduce distressing feelings and to avoid potential drug induced diseases, we attempted to image retina with dilated pupil and froze accommodation without drugs. An optimized liquid crystal adaptive optics camera was adopted for retinal imaging. A novel eye stared system was used for stimulating accommodation and fixating imaging area. Illumination sources and imaging camera kept linkage for focusing and imaging different layers. Four subjects with diverse degree of myopia were imaged. Based on the optical properties of the human eye, the eye stared system reduced the defocus to less than the typical ocular depth of focus. In this way, the illumination light can be projected on certain retina layer precisely. Since that the defocus had been compensated by the eye stared system, the adopted 512 × 512 liquid crystal spatial light modulator (LC-SLM) corrector provided the crucial spatial fidelity to fully compensate high-order aberrations. The Strehl ratio of a subject with -8 diopter myopia was improved to 0.78, which was nearly close to diffraction-limited imaging. By finely adjusting the axial displacement of illumination sources and imaging camera, cone photoreceptors, blood vessels and nerve fiber layer were clearly imaged successfully.
Virtual-stereo fringe reflection technique for specular free-form surface testing
NASA Astrophysics Data System (ADS)
Ma, Suodong; Li, Bo
2016-11-01
Due to their excellent ability to improve the performance of optical systems, free-form optics have attracted extensive interest in many fields, e.g. optical design of astronomical telescopes, laser beam expanders, spectral imagers, etc. However, compared with traditional simple ones, testing for such kind of optics is usually more complex and difficult which has been being a big barrier for the manufacture and the application of these optics. Fortunately, owing to the rapid development of electronic devices and computer vision technology, fringe reflection technique (FRT) with advantages of simple system structure, high measurement accuracy and large dynamic range is becoming a powerful tool for specular free-form surface testing. In order to obtain absolute surface shape distributions of test objects, two or more cameras are often required in the conventional FRT which makes the system structure more complex and the measurement cost much higher. Furthermore, high precision synchronization between each camera is also a troublesome issue. To overcome the aforementioned drawback, a virtual-stereo FRT for specular free-form surface testing is put forward in this paper. It is able to achieve absolute profiles with the help of only one single biprism and a camera meanwhile avoiding the problems of stereo FRT based on binocular or multi-ocular cameras. Preliminary experimental results demonstrate the feasibility of the proposed technique.
Visual Target Tracking in the Presence of Unknown Observer Motion
NASA Technical Reports Server (NTRS)
Williams, Stephen; Lu, Thomas
2009-01-01
Much attention has been given to the visual tracking problem due to its obvious uses in military surveillance. However, visual tracking is complicated by the presence of motion of the observer in addition to the target motion, especially when the image changes caused by the observer motion are large compared to those caused by the target motion. Techniques for estimating the motion of the observer based on image registration techniques and Kalman filtering are presented and simulated. With the effects of the observer motion removed, an additional phase is implemented to track individual targets. This tracking method is demonstrated on an image stream from a buoy-mounted or periscope-mounted camera, where large inter-frame displacements are present due to the wave action on the camera. This system has been shown to be effective at tracking and predicting the global position of a planar vehicle (boat) being observed from a single, out-of-plane camera. Finally, the tracking system has been extended to a multi-target scenario.
Homography-based multiple-camera person-tracking
NASA Astrophysics Data System (ADS)
Turk, Matthew R.
2009-01-01
Multiple video cameras are cheaply installed overlooking an area of interest. While computerized single-camera tracking is well-developed, multiple-camera tracking is a relatively new problem. The main multi-camera problem is to give the same tracking label to all projections of a real-world target. This is called the consistent labelling problem. Khan and Shah (2003) introduced a method to use field of view lines to perform multiple-camera tracking. The method creates inter-camera meta-target associations when objects enter at the scene edges. They also said that a plane-induced homography could be used for tracking, but this method was not well described. Their homography-based system would not work if targets use only one side of a camera to enter the scene. This paper overcomes this limitation and fully describes a practical homography-based tracker. A new method to find the feet feature is introduced. The method works especially well if the camera is tilted, when using the bottom centre of the target's bounding-box would produce inaccurate results. The new method is more accurate than the bounding-box method even when the camera is not tilted. Next, a method is presented that uses a series of corresponding point pairs "dropped" by oblivious, live human targets to find a plane-induced homography. The point pairs are created by tracking the feet locations of moving targets that were associated using the field of view line method. Finally, a homography-based multiple-camera tracking algorithm is introduced. Rules governing when to create the homography are specified. The algorithm ensures that homography-based tracking only starts after a non-degenerate homography is found. The method works when not all four field of view lines are discoverable; only one line needs to be found to use the algorithm. To initialize the system, the operator must specify pairs of overlapping cameras. Aside from that, the algorithm is fully automatic and uses the natural movement of live targets for training. No calibration is required. Testing shows that the algorithm performs very well in real-world sequences. The consistent labelling problem is solved, even for targets that appear via in-scene entrances. Full occlusions are handled. Although implemented in Matlab, the multiple-camera tracking system runs at eight frames per second. A faster implementation would be suitable for real-world use at typical video frame rates.
Determining fast orientation changes of multi-spectral line cameras from the primary images
NASA Astrophysics Data System (ADS)
Wohlfeil, Jürgen
2012-01-01
Fast orientation changes of airborne and spaceborne line cameras cannot always be avoided. In such cases it is essential to measure them with high accuracy to ensure a good quality of the resulting imagery products. Several approaches exist to support the orientation measurement by using optical information received through the main objective/telescope. In this article an approach is proposed that allows the determination of non-systematic orientation changes between every captured line. It does not require any additional camera hardware or onboard processing capabilities but the payload images and a rough estimate of the camera's trajectory. The approach takes advantage of the typical geometry of multi-spectral line cameras with a set of linear sensor arrays for different spectral bands on the focal plane. First, homologous points are detected within the heavily distorted images of different spectral bands. With their help a connected network of geometrical correspondences can be built up. This network is used to calculate the orientation changes of the camera with the temporal and angular resolution of the camera. The approach was tested with an extensive set of aerial surveys covering a wide range of different conditions and achieved precise and reliable results.
NASA Astrophysics Data System (ADS)
Bohlander, J. A.; Ross, R.; Scambos, T.; Haran, T. M.; Bauer, R. J.
2012-12-01
The Automated Meteorology - Ice/Indigenous species - Geophysics Observation System (AMIGOS) consists of a set of measurement instruments and camera(s) controlled by a single-board computer with a simplified Linux operating system and an Iridium satellite modem supporting two-way communication. Primary features of the system relevant to polar operations are low power requirements, daily data uploading, reprogramming, tolerance for low temperatures, and various approaches for automatic resets and recovery from low power or cold shut-down. Instruments include a compact weather station, C/A or dual-frequency GPS, solar flux and reflectivity sensors, sonic snow gages, simplified radio-echo-sounder, and resistance thermometer string in the firn column. In the current state of development, there are two basic designs. One is intended for in situ observations of glacier conditions. The other design supports a high-resolution camera for monitoring biological or geophysical systems from short distances (100 m to 20 km). The stations have been successfully used in several locations for operational support, monitoring rapid ice changes in response to climate change or iceberg drift, and monitoring penguin colony activity. As of June, 2012, there are 9 AMIGOS systems installed, all on the Antarctic continent. The stations are a working prototype for a planned series of upgraded stations, currently termed 'Sentinels'. These stations would carry further instrumentation, communications, and processing capability to investigate ice - ocean interaction from ice tongue, ice shelf, or fjord coastline areas.
2007-12-03
and reference datums, in addition to other field positioning tasks. 3.5.3. Navigation Systems An Applanix 510 A/V POS system was co-mounted with...Cal and POS EO from Applanix Corp. lmageStation Suite from Z/1 Imaging Images: Camera and Data Recorder · I SAT Aerial Triangulation Software
VSF Measurements and Inversion for RaDyO
2012-09-30
near-surface waters, including the surf zone. APPROACH MASCOT (Multi-Angle SCattering Optical Tool) has a 30 mW 658 nm laser diode source...in Santa Barbara Channel are provided in Fig. 1. Despite the widespread use of polarized laser sources across a diversity of Navy applications, this...operations that rely on divers, cameras, laser imaging systems, and active and passive remote sensing systems. These include mine countermeasures, harbor
A single pixel camera video ophthalmoscope
NASA Astrophysics Data System (ADS)
Lochocki, B.; Gambin, A.; Manzanera, S.; Irles, E.; Tajahuerce, E.; Lancis, J.; Artal, P.
2017-02-01
There are several ophthalmic devices to image the retina, from fundus cameras capable to image the whole fundus to scanning ophthalmoscopes with photoreceptor resolution. Unfortunately, these devices are prone to a variety of ocular conditions like defocus and media opacities, which usually degrade the quality of the image. Here, we demonstrate a novel approach to image the retina in real-time using a single pixel camera, which has the potential to circumvent those optical restrictions. The imaging procedure is as follows: a set of spatially coded patterns is projected rapidly onto the retina using a digital micro mirror device. At the same time, the inner product's intensity is measured for each pattern with a photomultiplier module. Subsequently, an image of the retina is reconstructed computationally. Obtained image resolution is up to 128 x 128 px with a varying real-time video framerate up to 11 fps. Experimental results obtained in an artificial eye confirm the tolerance against defocus compared to a conventional multi-pixel array based system. Furthermore, the use of a multiplexed illumination offers a SNR improvement leading to a lower illumination of the eye and hence an increase in patient's comfort. In addition, the proposed system could enable imaging in wavelength ranges where cameras are not available.
2001-11-26
KENNEDY SPACE CENTER, Fla. -- A piece of equipment for Hubble Space Telescope Servicing mission is moved inside Hangar AE, Cape Canaveral. In the canister is the Advanced Camera for Surveys (ACS). The ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. The goal of the mission, STS-109, is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002
2001-11-29
KENNEDY SPACE CENTER, Fla. -- In Hangar A&E, workers watch as an overhead crane lifts the Advanced Camera for Surveys out of its transportation container. Part of the payload on the Hubble Space Telescope Servicing Mission, STS-109, the ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. Tasks for the mission include replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002
2001-11-26
KENNEDY SPACE CENTER, Fla. - A piece of equipment for Hubble Space Telescope Servicing mission arrives at Hangar AE, Cape Canaveral. Inside the canister is the Advanced Camera for Surveys (ACS). The ACS will increase the discovery efficiency of the HST by a factor of ten. It consists of three electronic cameras and a complement of filters and dispersers that detect light from the ultraviolet to the near infrared (1200 - 10,000 angstroms). The ACS was built through a collaborative effort between Johns Hopkins University, Goddard Space Flight Center, Ball Aerospace Corporation and Space Telescope Science Institute. The goal of the mission, STS-109, is to service the HST, replacing Solar Array 2 with Solar Array 3, replacing the Power Control Unit, removing the Faint Object Camera and installing the ACS, installing the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, and installing New Outer Blanket Layer insulation on bays 5 through 8. Mission STS-109 is scheduled for launch Feb. 14, 2002
NASA Astrophysics Data System (ADS)
Reddy, V.; Le Corre, L.; Nathues, A.; Hall, I.; Gutierrez-Marques, P.; Hoffmann, M.
2011-10-01
The Dawn mission will rendezvous with asteroid (4) Vesta in July 2011. We have developed a set of equations for extracting mean pyroxene chemistry (Ferrosilite and Wollastonite) for classifying terrains on Vesta by using the Dawn Framing Camera (FC) multi-color bands. The Automated Spectral System (ASS) utilizes pseudo-Band I minima to estimate the mean pyroxene chemistry of diogenites, and basaltic eucrites. The mean pyroxene chemistries of cumulate eucrites, and howardites overlap each other on the pyroxene quadrilateral and hence are harder to distinguish. We expect our ASS to carry a bulk of the terrain classification and mineralogy workload utilizing these equations and complement the work of DawnKey (Le Corre et al., 2011, DPS/EPSC 2011). The system will also provide surface mineral chemistry layers that can be used for mapping Vesta's surface.
MEGARA: the new multi-object and integral field spectrograph for GTC
NASA Astrophysics Data System (ADS)
Carrasco, E.; Páez, G.; Izazaga-Pére, R.; Gil de Paz, A.; Gallego, J.; Iglesias-Páramo, J.
2017-07-01
MEGARA is an optical integral-field unit and multi-object spectrograph for the 10.4m Gran Telescopio Canarias. Both observational modes will provide identical spectral resolutions Rfwhm ˜ 6,000, 12,000 and 18,700. The spectrograph is a collimator-camera system. The unique characteristics of MEGARA in terms of throughput and versatility make this instrument the most efficient tool to date to analyze astrophysical objects at intermediate spectral resolutions. The instrument is currently at the telescope for on-sky commissioning. Here we describe the as-built main characteristics the instrument.
NASA Astrophysics Data System (ADS)
Blaser, S.; Nebiker, S.; Cavegn, S.
2017-05-01
Image-based mobile mapping systems enable the efficient acquisition of georeferenced image sequences, which can later be exploited in cloud-based 3D geoinformation services. In order to provide a 360° coverage with accurate 3D measuring capabilities, we present a novel 360° stereo panoramic camera configuration. By using two 360° panorama cameras tilted forward and backward in combination with conventional forward and backward looking stereo camera systems, we achieve a full 360° multi-stereo coverage. We furthermore developed a fully operational new mobile mapping system based on our proposed approach, which fulfils our high accuracy requirements. We successfully implemented a rigorous sensor and system calibration procedure, which allows calibrating all stereo systems with a superior accuracy compared to that of previous work. Our study delivered absolute 3D point accuracies in the range of 4 to 6 cm and relative accuracies of 3D distances in the range of 1 to 3 cm. These results were achieved in a challenging urban area. Furthermore, we automatically reconstructed a 3D city model of our study area by employing all captured and georeferenced mobile mapping imagery. The result is a very high detailed and almost complete 3D city model of the street environment.
Robertson, Daniel; Polf, Jerimy C; Peterson, Steve W; Gillin, Michael T; Beddar, Sam
2011-01-01
Prompt gamma rays emitted from biological tissues during proton irradiation carry dosimetric and spectroscopic information that can assist with treatment verification and provide an indication of the biological response of the irradiated tissues. Compton cameras are capable of determining the origin and energy of gamma rays. However, prompt gamma monitoring during proton therapy requires new Compton camera designs that perform well at the high gamma energies produced when tissues are bombarded with therapeutic protons. In this study we optimize the materials and geometry of a three-stage Compton camera for prompt gamma detection and calculate the theoretical efficiency of such a detector. The materials evaluated in this study include germanium, bismuth germanate (BGO), NaI, xenon, silicon and lanthanum bromide (LaBr3). For each material, the dimensions of each detector stage were optimized to produce the maximum number of relevant interactions. These results were used to predict the efficiency of various multi-material cameras. The theoretical detection efficiencies of the most promising multi-material cameras were then calculated for the photons emitted from a tissue-equivalent phantom irradiated by therapeutic proton beams ranging from 50 to 250 MeV. The optimized detector stages had a lateral extent of 10 × 10 cm2 with the thickness of the initial two stages dependent on the detector material. The thickness of the third stage was fixed at 10 cm regardless of material. The most efficient single-material cameras were composed of germanium (3 cm) and BGO (2.5 cm). These cameras exhibited efficiencies of 1.15 × 10−4 and 9.58 × 10−5 per incident proton, respectively. The most efficient multi-material camera design consisted of two initial stages of germanium (3 cm) and a final stage of BGO, resulting in a theoretical efficiency of 1.26 × 10−4 per incident proton. PMID:21508442
Pulse Based Time-of-Flight Range Sensing.
Sarbolandi, Hamed; Plack, Markus; Kolb, Andreas
2018-05-23
Pulse-based Time-of-Flight (PB-ToF) cameras are an attractive alternative range imaging approach, compared to the widely commercialized Amplitude Modulated Continuous-Wave Time-of-Flight (AMCW-ToF) approach. This paper presents an in-depth evaluation of a PB-ToF camera prototype based on the Hamamatsu area sensor S11963-01CR. We evaluate different ToF-related effects, i.e., temperature drift, systematic error, depth inhomogeneity, multi-path effects, and motion artefacts. Furthermore, we evaluate the systematic error of the system in more detail, and introduce novel concepts to improve the quality of range measurements by modifying the mode of operation of the PB-ToF camera. Finally, we describe the means of measuring the gate response of the PB-ToF sensor and using this information for PB-ToF sensor simulation.
A Multi-Camera System for Bioluminescence Tomography in Preclinical Oncology Research
Lewis, Matthew A.; Richer, Edmond; Slavine, Nikolai V.; Kodibagkar, Vikram D.; Soesbe, Todd C.; Antich, Peter P.; Mason, Ralph P.
2013-01-01
Bioluminescent imaging (BLI) of cells expressing luciferase is a valuable noninvasive technique for investigating molecular events and tumor dynamics in the living animal. Current usage is often limited to planar imaging, but tomographic imaging can enhance the usefulness of this technique in quantitative biomedical studies by allowing accurate determination of tumor size and attribution of the emitted light to a specific organ or tissue. Bioluminescence tomography based on a single camera with source rotation or mirrors to provide additional views has previously been reported. We report here in vivo studies using a novel approach with multiple rotating cameras that, when combined with image reconstruction software, provides the desired representation of point source metastases and other small lesions. Comparison with MRI validated the ability to detect lung tumor colonization in mouse lung. PMID:26824926
Pipe inspection and repair system
NASA Technical Reports Server (NTRS)
Schempf, Hagen (Inventor); Mutschler, Edward (Inventor); Chemel, Brian (Inventor); Boehmke, Scott (Inventor); Crowley, William (Inventor)
2004-01-01
A multi-module pipe inspection and repair device. The device includes a base module, a camera module, a sensor module, an MFL module, a brush module, a patch set/test module, and a marker module. Each of the modules may be interconnected to construct one of an inspection device, a preparation device, a marking device, and a repair device.
EVA 5 - MS Grunsfeld and Linnehan in payload bay
2002-03-08
STS109-E-5750 (8 March 2002) --- Astronaut John M. Grunsfeld, STS-109 payload commander, floats near the giant Hubble Space Telescope (HST) temporarily hosted in the Space Shuttle Columbias cargo bay. Astronaut Richard M. Linnehan (lower right), mission specialist, works in tandem with Grunsfeld during this fifth and final scheduled space walk. Activities for EVA-5 centered around the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) to install a Cryogenic Cooler and its Cooling System Radiator. The space walk was completed at 10:06 a.m. CST (1606 GMT), March 8, 2002. The image was recorded with a digital still camera.
Neuro-Analogical Gate Tuning of Trajectory Data Fusion for a Mecanum-Wheeled Special Needs Chair
ElSaharty, M. A.; zakzouk, Ezz Eldin
2017-01-01
Trajectory tracking of mobile wheeled chairs using internal shaft encoder and inertia measurement unit(IMU), exhibits several complications and accumulated errors in the tracking process due to wheel slippage, offset drift and integration approximations. These errors can be realized when comparing localization results from such sensors with a camera tracking system. In long trajectory tracking, such errors can accumulate and result in significant deviations which make data from these sensors unreliable for tracking. Meanwhile the utilization of an external camera tracking system is not always a feasible solution depending on the implementation environment. This paper presents a novel sensor fusion method that combines the measurements of internal sensors to accurately predict the location of the wheeled chair in an environment. The method introduces a new analogical OR gate structured with tuned parameters using multi-layer feedforward neural network denoted as “Neuro-Analogical Gate” (NAG). The resulting system minimize any deviation error caused by the sensors, thus accurately tracking the wheeled chair location without the requirement of an external camera tracking system. The fusion methodology has been tested with a prototype Mecanum wheel-based chair, and significant improvement over tracking response, error and performance has been observed. PMID:28045973
Secoli, R; Zondervan, D; Reinkensmeyer, D
2012-01-01
For children with a severe disability, such as can arise from cerebral palsy, becoming independent in mobility is a critical goal. Currently, however, driver's training for powered wheelchair use is labor intensive, requiring hand-over-hand assistance from a skilled therapist to keep the trainee safe. This paper describes the design of a mixed reality environment for semi-autonomous training of wheelchair driving skills. In this system, the wheelchair is used as the gaming input device, and users train driving skills by maneuvering through floor-projected games created with a multi-projector system and a multi-camera tracking system. A force feedback joystick assists in steering and enhances safety.
Multi-viewer tracking integral imaging system and its viewing zone analysis.
Park, Gilbae; Jung, Jae-Hyun; Hong, Keehoon; Kim, Yunhee; Kim, Young-Hoon; Min, Sung-Wook; Lee, Byoungho
2009-09-28
We propose a multi-viewer tracking integral imaging system for viewing angle and viewing zone improvement. In the tracking integral imaging system, the pickup angles in each elemental lens in the lens array are decided by the positions of viewers, which means the elemental image can be made for each viewer to provide wider viewing angle and larger viewing zone. Our tracking integral imaging system is implemented with an infrared camera and infrared light emitting diodes which can track the viewers' exact positions robustly. For multiple viewers to watch integrated three-dimensional images in the tracking integral imaging system, it is needed to formulate the relationship between the multiple viewers' positions and the elemental images. We analyzed the relationship and the conditions for the multiple viewers, and verified them by the implementation of two-viewer tracking integral imaging system.
NASA Astrophysics Data System (ADS)
Bauer, Jacob R.; van Beekum, Karlijn; Klaessens, John; Noordmans, Herke Jan; Boer, Christa; Hardeberg, Jon Y.; Verdaasdonk, Rudolf M.
2018-02-01
Non contact spatial resolved oxygenation measurements remain an open challenge in the biomedical field and non contact patient monitoring. Although point measurements are the clinical standard till this day, regional differences in the oxygenation will improve the quality and safety of care. Recent developments in spectral imaging resulted in spectral filter array cameras (SFA). These provide the means to acquire spatial spectral videos in real-time and allow a spatial approach to spectroscopy. In this study, the performance of a 25 channel near infrared SFA camera was studied to obtain spatial oxygenation maps of hands during an occlusion of the left upper arm in 7 healthy volunteers. For comparison a clinical oxygenation monitoring system, INVOS, was used as a reference. In case of the NIRS SFA camera, oxygenation curves were derived from 2-3 wavelength bands with a custom made fast analysis software using a basic algorithm. Dynamic oxygenation changes were determined with the NIR SFA camera and INVOS system at different regional locations of the occluded versus non-occluded hands and showed to be in good agreement. To increase the signal to noise ratio, algorithm and image acquisition were optimised. The measurement were robust to different illumination conditions with NIR light sources. This study shows that imaging of relative oxygenation changes over larger body areas is potentially possible in real time.
Multi-frame image processing with panning cameras and moving subjects
NASA Astrophysics Data System (ADS)
Paolini, Aaron; Humphrey, John; Curt, Petersen; Kelmelis, Eric
2014-06-01
Imaging scenarios commonly involve erratic, unpredictable camera behavior or subjects that are prone to movement, complicating multi-frame image processing techniques. To address these issues, we developed three techniques that can be applied to multi-frame image processing algorithms in order to mitigate the adverse effects observed when cameras are panning or subjects within the scene are moving. We provide a detailed overview of the techniques and discuss the applicability of each to various movement types. In addition to this, we evaluated algorithm efficacy with demonstrated benefits using field test video, which has been processed using our commercially available surveillance product. Our results show that algorithm efficacy is significantly improved in common scenarios, expanding our software's operational scope. Our methods introduce little computational burden, enabling their use in real-time and low-power solutions, and are appropriate for long observation periods. Our test cases focus on imaging through turbulence, a common use case for multi-frame techniques. We present results of a field study designed to test the efficacy of these techniques under expanded use cases.
A new omni-directional multi-camera system for high resolution surveillance
NASA Astrophysics Data System (ADS)
Cogal, Omer; Akin, Abdulkadir; Seyid, Kerem; Popovic, Vladan; Schmid, Alexandre; Ott, Beat; Wellig, Peter; Leblebici, Yusuf
2014-05-01
Omni-directional high resolution surveillance has a wide application range in defense and security fields. Early systems used for this purpose are based on parabolic mirror or fisheye lens where distortion due to the nature of the optical elements cannot be avoided. Moreover, in such systems, the image resolution is limited to a single image sensor's image resolution. Recently, the Panoptic camera approach that mimics the eyes of flying insects using multiple imagers has been presented. This approach features a novel solution for constructing a spherically arranged wide FOV plenoptic imaging system where the omni-directional image quality is limited by low-end sensors. In this paper, an overview of current Panoptic camera designs is provided. New results for a very-high resolution visible spectrum imaging and recording system inspired from the Panoptic approach are presented. The GigaEye-1 system, with 44 single cameras and 22 FPGAs, is capable of recording omni-directional video in a 360°×100° FOV at 9.5 fps with a resolution over (17,700×4,650) pixels (82.3MP). Real-time video capturing capability is also verified at 30 fps for a resolution over (9,000×2,400) pixels (21.6MP). The next generation system with significantly higher resolution and real-time processing capacity, called GigaEye-2, is currently under development. The important capacity of GigaEye-1 opens the door to various post-processing techniques in surveillance domain such as large perimeter object tracking, very-high resolution depth map estimation and high dynamicrange imaging which are beyond standard stitching and panorama generation methods.
Automatic camera to laser calibration for high accuracy mobile mapping systems using INS
NASA Astrophysics Data System (ADS)
Goeman, Werner; Douterloigne, Koen; Gautama, Sidharta
2013-09-01
A mobile mapping system (MMS) is a mobile multi-sensor platform developed by the geoinformation community to support the acquisition of huge amounts of geodata in the form of georeferenced high resolution images and dense laser clouds. Since data fusion and data integration techniques are increasingly able to combine the complementary strengths of different sensor types, the external calibration of a camera to a laser scanner is a common pre-requisite on today's mobile platforms. The methods of calibration, nevertheless, are often relatively poorly documented, are almost always time-consuming, demand expert knowledge and often require a carefully constructed calibration environment. A new methodology is studied and explored to provide a high quality external calibration for a pinhole camera to a laser scanner which is automatic, easy to perform, robust and foolproof. The method presented here, uses a portable, standard ranging pole which needs to be positioned on a known ground control point. For calibration, a well studied absolute orientation problem needs to be solved. In many cases, the camera and laser sensor are calibrated in relation to the INS system. Therefore, the transformation from camera to laser contains the cumulated error of each sensor in relation to the INS. Here, the calibration of the camera is performed in relation to the laser frame using the time synchronization between the sensors for data association. In this study, the use of the inertial relative movement will be explored to collect more useful calibration data. This results in a better intersensor calibration allowing better coloring of the clouds and a more accurate depth mask for images, especially on the edges of objects in the scene.
NV-CMOS HD camera for day/night imaging
NASA Astrophysics Data System (ADS)
Vogelsong, T.; Tower, J.; Sudol, Thomas; Senko, T.; Chodelka, D.
2014-06-01
SRI International (SRI) has developed a new multi-purpose day/night video camera with low-light imaging performance comparable to an image intensifier, while offering the size, weight, ruggedness, and cost advantages enabled by the use of SRI's NV-CMOS HD digital image sensor chip. The digital video output is ideal for image enhancement, sharing with others through networking, video capture for data analysis, or fusion with thermal cameras. The camera provides Camera Link output with HD/WUXGA resolution of 1920 x 1200 pixels operating at 60 Hz. Windowing to smaller sizes enables operation at higher frame rates. High sensitivity is achieved through use of backside illumination, providing high Quantum Efficiency (QE) across the visible and near infrared (NIR) bands (peak QE <90%), as well as projected low noise (<2h+) readout. Power consumption is minimized in the camera, which operates from a single 5V supply. The NVCMOS HD camera provides a substantial reduction in size, weight, and power (SWaP) , ideal for SWaP-constrained day/night imaging platforms such as UAVs, ground vehicles, fixed mount surveillance, and may be reconfigured for mobile soldier operations such as night vision goggles and weapon sights. In addition the camera with the NV-CMOS HD imager is suitable for high performance digital cinematography/broadcast systems, biofluorescence/microscopy imaging, day/night security and surveillance, and other high-end applications which require HD video imaging with high sensitivity and wide dynamic range. The camera comes with an array of lens mounts including C-mount and F-mount. The latest test data from the NV-CMOS HD camera will be presented.
Reliability Analysis of the MSC System
NASA Astrophysics Data System (ADS)
Kim, Young-Soo; Lee, Do-Kyoung; Lee, Chang-Ho; Woo, Sun-Hee
2003-09-01
MSC (Multi-Spectral Camera) is the payload of KOMPSAT-2, which is being developed for earth imaging in optical and near-infrared region. The design of the MSC is completed and its reliability has been assessed from part level to the MSC system level. The reliability was analyzed in worst case and the analysis results showed that the value complies the required value of 0.9. In this paper, a calculation method of reliability for the MSC system is described, and assessment result is presented and discussed.
A Bionic Camera-Based Polarization Navigation Sensor
Wang, Daobin; Liang, Huawei; Zhu, Hui; Zhang, Shuai
2014-01-01
Navigation and positioning technology is closely related to our routine life activities, from travel to aerospace. Recently it has been found that Cataglyphis (a kind of desert ant) is able to detect the polarization direction of skylight and navigate according to this information. This paper presents a real-time bionic camera-based polarization navigation sensor. This sensor has two work modes: one is a single-point measurement mode and the other is a multi-point measurement mode. An indoor calibration experiment of the sensor has been done under a beam of standard polarized light. The experiment results show that after noise reduction the accuracy of the sensor can reach up to 0.3256°. It is also compared with GPS and INS (Inertial Navigation System) in the single-point measurement mode through an outdoor experiment. Through time compensation and location compensation, the sensor can be a useful alternative to GPS and INS. In addition, the sensor also can measure the polarization distribution pattern when it works in multi-point measurement mode. PMID:25051029
NASA Astrophysics Data System (ADS)
Anan, Tetsu; Huang, Yu-Wei; Nakatani, Yoshikazu; Ichimoto, Kiyoshi; UeNo, Satoru; Kimura, Goichi; Ninomiya, Shota; Okada, Sanetaka; Kaneda, Naoki
2018-05-01
To obtain full Stokes spectra in multi-wavelength windows simultaneously, we developed a new spectro-polarimeter on the Domeless Solar Telescope at Hida Observatory. The new polarimeter consists of a 60 cm aperture vacuum telescope on an altazimuth mounting, an image rotator, a high-dispersion spectrograph, and a polarization modulator and an analyzer composed of a continuously rotating waveplate with a retardation that is nearly constant at around 127° in 500-1100 nm. There are also a polarizing beam splitter located close behind the focus of the telescope, fast and large format CMOS cameras, and an infrared camera. A slit spectrograph allows us to obtain spectra in as many wavelength windows as the number of cameras. We characterized the instrumental polarization of the entire system and established a polarization calibration procedure. The cross-talks among the Stokes Q, U, and V have been evaluated to be about 0.06%-1.2%, depending on the degree of the intrinsic polarizations. In a typical observing setup, a sensitivity of 0.03% can be achieved in 20-60 seconds for 500-1100 nm. The new polarimeter is expected to provide a powerful tool for diagnosing the 3D magnetic field and other vector physical quantities in the solar atmosphere.
Multi-target detection and positioning in crowds using multiple camera surveillance
NASA Astrophysics Data System (ADS)
Huang, Jiahu; Zhu, Qiuyu; Xing, Yufeng
2018-04-01
In this study, we propose a pixel correspondence algorithm for positioning in crowds based on constraints on the distance between lines of sight, grayscale differences, and height in a world coordinates system. First, a Gaussian mixture model is used to obtain the background and foreground from multi-camera videos. Second, the hair and skin regions are extracted as regions of interest. Finally, the correspondences between each pixel in the region of interest are found under multiple constraints and the targets are positioned by pixel clustering. The algorithm can provide appropriate redundancy information for each target, which decreases the risk of losing targets due to a large viewing angle and wide baseline. To address the correspondence problem for multiple pixels, we construct a pixel-based correspondence model based on a similar permutation matrix, which converts the correspondence problem into a linear programming problem where a similar permutation matrix is found by minimizing an objective function. The correct pixel correspondences can be obtained by determining the optimal solution of this linear programming problem and the three-dimensional position of the targets can also be obtained by pixel clustering. Finally, we verified the algorithm with multiple cameras in experiments, which showed that the algorithm has high accuracy and robustness.
VizieR Online Data Catalog: Antennae galaxies (NGC 4038/4039) revisited (Whitmore+, 2010)
NASA Astrophysics Data System (ADS)
Whitmore, B. C.; Chandar, R.; Schweizer, F.; Rothberg, B.; Leitherer, C.; Rieke, M.; Rieke, G.; Blair, W. P.; Mengel, S.; Alonso-Herrero, A.
2012-06-01
Observations of the main bodies of NGC 4038/39 were made with the Hubble Space Telescope (HST), using the ACS, as part of Program GO-10188. Multi-band photometry was obtained in the following optical broadband filters: F435W (~B), F550M (~V), and F814W (~I). Archival F336W photometry of the Antennae (Program GO-5962) was used to supplement our optical ACS/WFC observations. Infrared observations were made using the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) camera on HST as part of Program GO-10188. Observations were made using the NIC2 camera with the F160W, F187N, and F237M filters, and the NIC3 camera with the F110W, F160W, F164W, F187N, and F222M filters. (10 data files).
Multi-scale auroral observations in Apatity: winter 2010-2011
NASA Astrophysics Data System (ADS)
Kozelov, B. V.; Pilgaev, S. V.; Borovkov, L. P.; Yurov, V. E.
2012-03-01
Routine observations of the aurora are conducted in Apatity by a set of five cameras: (i) all-sky TV camera Watec WAT-902K (1/2"CCD) with Fujinon lens YV2.2 × 1.4A-SA2; (ii) two monochromatic cameras Guppy F-044B NIR (1/2"CCD) with Fujinon HF25HA-1B (1:1.4/25 mm) lens for 18° field of view and glass filter 558 nm; (iii) two color cameras Guppy F-044C NIR (1/2"CCD) with Fujinon DF6HA-1B (1:1.2/6 mm) lens for 67° field of view. The observational complex is aimed at investigating spatial structure of the aurora, its scaling properties, and vertical distribution in the rayed forms. The cameras were installed on the main building of the Apatity division of the Polar Geophysical Institute and at the Apatity stratospheric range. The distance between these sites is nearly 4 km, so the identical monochromatic cameras can be used as a stereoscopic system. All cameras are accessible and operated remotely via Internet. For 2010-2011 winter season the equipment was upgraded by special blocks of GPS-time triggering, temperature control and motorized pan-tilt rotation mounts. This paper presents the equipment, samples of observed events and the web-site with access to available data previews.
Multi-scale auroral observations in Apatity: winter 2010-2011
NASA Astrophysics Data System (ADS)
Kozelov, B. V.; Pilgaev, S. V.; Borovkov, L. P.; Yurov, V. E.
2011-12-01
Routine observations of the aurora are conducted in Apatity by a set of five cameras: (i) all-sky TV camera Watec WAT-902K (1/2"CCD) with Fujinon lens YV2.2 × 1.4A-SA2; (ii) two monochromatic cameras Guppy F-044B NIR (1/2"CCD) with Fujinon HF25HA-1B (1:1.4/25 mm) lens for 18° field of view and glass filter 558 nm; (iii) two color cameras Guppy F-044C NIR (1/2"CCD) with Fujinon DF6HA-1B (1:1.2/6 mm) lens for 67° field of view. The observational complex is aimed at investigating spatial structure of the aurora, its scaling properties, and vertical distribution in the rayed forms. The cameras were installed on the main building of the Apatity division of the Polar Geophysical Institute and at the Apatity stratospheric range. The distance between these sites is nearly 4 km, so the identical monochromatic cameras can be used as a stereoscopic system. All cameras are accessible and operated remotely via Internet. For 2010-2011 winter season the equipment was upgraded by special blocks of GPS-time triggering, temperature control and motorized pan-tilt rotation mounts. This paper presents the equipment, samples of observed events and the web-site with access to available data previews.
Multi-Touch Tabletop System Using Infrared Image Recognition for User Position Identification.
Suto, Shota; Watanabe, Toshiya; Shibusawa, Susumu; Kamada, Masaru
2018-05-14
A tabletop system can facilitate multi-user collaboration in a variety of settings, including small meetings, group work, and education and training exercises. The ability to identify the users touching the table and their positions can promote collaborative work among participants, so methods have been studied that involve attaching sensors to the table, chairs, or to the users themselves. An effective method of recognizing user actions without placing a burden on the user would be some type of visual process, so the development of a method that processes multi-touch gestures by visual means is desired. This paper describes the development of a multi-touch tabletop system using infrared image recognition for user position identification and presents the results of touch-gesture recognition experiments and a system-usability evaluation. Using an inexpensive FTIR touch panel and infrared light, this system picks up the touch areas and the shadow area of the user's hand by an infrared camera to establish an association between the hand and table touch points and estimate the position of the user touching the table. The multi-touch gestures prepared for this system include an operation to change the direction of an object to face the user and a copy operation in which two users generate duplicates of an object. The system-usability evaluation revealed that prior learning was easy and that system operations could be easily performed.
Multi-Touch Tabletop System Using Infrared Image Recognition for User Position Identification
Suto, Shota; Watanabe, Toshiya; Shibusawa, Susumu; Kamada, Masaru
2018-01-01
A tabletop system can facilitate multi-user collaboration in a variety of settings, including small meetings, group work, and education and training exercises. The ability to identify the users touching the table and their positions can promote collaborative work among participants, so methods have been studied that involve attaching sensors to the table, chairs, or to the users themselves. An effective method of recognizing user actions without placing a burden on the user would be some type of visual process, so the development of a method that processes multi-touch gestures by visual means is desired. This paper describes the development of a multi-touch tabletop system using infrared image recognition for user position identification and presents the results of touch-gesture recognition experiments and a system-usability evaluation. Using an inexpensive FTIR touch panel and infrared light, this system picks up the touch areas and the shadow area of the user’s hand by an infrared camera to establish an association between the hand and table touch points and estimate the position of the user touching the table. The multi-touch gestures prepared for this system include an operation to change the direction of an object to face the user and a copy operation in which two users generate duplicates of an object. The system-usability evaluation revealed that prior learning was easy and that system operations could be easily performed. PMID:29758006
Multiple-frame IR photo-recorder KIT-3M
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roos, E; Wilkins, P; Nebeker, N
2006-05-15
This paper reports the experimental results of a high-speed multi-frame infrared camera which has been developed in Sarov at VNIIEF. Earlier [1] we discussed the possibility of creation of the multi-frame infrared radiation photo-recorder with framing frequency about 1 MHz. The basis of the photo-recorder is a semiconductor ionization camera [2, 3], which converts IR radiation of spectral range 1-10 micrometers into a visible image. Several sequential thermal images are registered by using the IR converter in conjunction with a multi-frame electron-optical camera. In the present report we discuss the performance characteristics of a prototype commercial 9-frame high-speed IR photo-recorder.more » The image converter records infrared images of thermal fields corresponding to temperatures ranging from 300 C to 2000 C with an exposure time of 1-20 {micro}s at a frame frequency up to 500 KHz. The IR-photo-recorder camera is useful for recording the time evolution of thermal fields in fast processes such as gas dynamics, ballistics, pulsed welding, thermal processing, automotive industry, aircraft construction, in pulsed-power electric experiments, and for the measurement of spatial mode characteristics of IR-laser radiation.« less
Development of compact Compton camera for 3D image reconstruction of radioactive contamination
NASA Astrophysics Data System (ADS)
Sato, Y.; Terasaka, Y.; Ozawa, S.; Nakamura Miyamura, H.; Kaburagi, M.; Tanifuji, Y.; Kawabata, K.; Torii, T.
2017-11-01
The Fukushima Daiichi Nuclear Power Station (FDNPS), operated by Tokyo Electric Power Company Holdings, Inc., went into meltdown after the large tsunami caused by the Great East Japan Earthquake of March 11, 2011. Very large amounts of radionuclides were released from the damaged plant. Radiation distribution measurements inside FDNPS buildings are indispensable to execute decommissioning tasks in the reactor buildings. We have developed a compact Compton camera to measure the distribution of radioactive contamination inside the FDNPS buildings three-dimensionally (3D). The total weight of the Compton camera is lower than 1.0 kg. The gamma-ray sensor of the Compton camera employs Ce-doped GAGG (Gd3Al2Ga3O12) scintillators coupled with a multi-pixel photon counter. Angular correction of the detection efficiency of the Compton camera was conducted. Moreover, we developed a 3D back-projection method using the multi-angle data measured with the Compton camera. We successfully observed 3D radiation images resulting from the two 137Cs radioactive sources, and the image of the 9.2 MBq source appeared stronger than that of the 2.7 MBq source.
NASA Astrophysics Data System (ADS)
Bruegge, Carol J.; Val, Sebastian; Diner, David J.; Jovanovic, Veljko; Gray, Ellyn; Di Girolamo, Larry; Zhao, Guangyu
2014-09-01
The Multi-angle Imaging SpectroRadiometer (MISR) has successfully operated on the EOS/ Terra spacecraft since 1999. It consists of nine cameras pointing from nadir to 70.5° view angle with four spectral channels per camera. Specifications call for a radiometric uncertainty of 3% absolute and 1% relative to the other cameras. To accomplish this, MISR utilizes an on-board calibrator (OBC) to measure camera response changes. Once every two months the two Spectralon panels are deployed to direct solar-light into the cameras. Six photodiode sets measure the illumination level that are compared to MISR raw digital numbers, thus determining the radiometric gain coefficients used in Level 1 data processing. Although panel stability is not required, there has been little detectable change in panel reflectance, attributed to careful preflight handling techniques. The cameras themselves have degraded in radiometric response by 10% since launch, but calibration updates using the detector-based scheme has compensated for these drifts and allowed the radiance products to meet accuracy requirements. Validation using Sahara desert observations show that there has been a drift of ~1% in the reported nadir-view radiance over a decade, common to all spectral bands.
A practical indoor context-aware surveillance system with multi-Kinect sensors
NASA Astrophysics Data System (ADS)
Jia, Lili; You, Ying; Li, Tiezhu; Zhang, Shun
2014-11-01
In this paper we develop a novel practical application, which give scalable services to the end users when abnormal actives are happening. Architecture of the application has been presented consisting of network infrared cameras and a communication module. In this intelligent surveillance system we use Kinect sensors as the input cameras. Kinect is an infrared laser camera which its user can access the raw infrared sensor stream. We install several Kinect sensors in one room to track the human skeletons. Each sensor returns the body positions with 15 coordinates in its own coordinate system. We use calibration algorithms to calibrate all the body positions points into one unified coordinate system. With the body positions points, we can infer the surveillance context. Furthermore, the messages from the metadata index matrix will be sent to mobile phone through communication module. User will instantly be aware of an abnormal case happened in the room without having to check the website. In conclusion, theoretical analysis and experimental results in this paper show that the proposed system is reasonable and efficient. And the application method introduced in this paper is not only to discourage the criminals and assist police in the apprehension of suspects, but also can enabled the end-users monitor the indoor environments anywhere and anytime by their phones.
2002-03-07
STS-109 Astronaut Michael J. Massimino, mission specialist, perched on the Shuttle's robotic arm, is preparing to install the Electronic Support Module (ESM) in the aft shroud of the Hubble Space telescope (HST), with the assistance of astronaut James H. Newman (out of frame). The module will support a new experimental cooling system to be installed during the next day's fifth and final space walk of the mission. That cooling system is designed to bring the telescope's Near-Infrared Camera and Multi Spectrometer (NICMOS) back to life the which had been dormant since January 1999 when its original coolant ran out. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. In addition to the installation of the experimental cooling system for the Hubble's Near-Infrared Camera and NICMOS, STS-109 upgrades to the HST included replacement of the solar array panels, replacement of the power control unit (PCU), and replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS). Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.
A multimodal image sensor system for identifying water stress in grapevines
NASA Astrophysics Data System (ADS)
Zhao, Yong; Zhang, Qin; Li, Minzan; Shao, Yongni; Zhou, Jianfeng; Sun, Hong
2012-11-01
Water stress is one of the most common limitations of fruit growth. Water is the most limiting resource for crop growth. In grapevines, as well as in other fruit crops, fruit quality benefits from a certain level of water deficit which facilitates to balance vegetative and reproductive growth and the flow of carbohydrates to reproductive structures. A multi-modal sensor system was designed to measure the reflectance signature of grape plant surfaces and identify different water stress levels in this paper. The multi-modal sensor system was equipped with one 3CCD camera (three channels in R, G, and IR). The multi-modal sensor can capture and analyze grape canopy from its reflectance features, and identify the different water stress levels. This research aims at solving the aforementioned problems. The core technology of this multi-modal sensor system could further be used as a decision support system that combines multi-modal sensory data to improve plant stress detection and identify the causes of stress. The images were taken by multi-modal sensor which could output images in spectral bands of near-infrared, green and red channel. Based on the analysis of the acquired images, color features based on color space and reflectance features based on image process method were calculated. The results showed that these parameters had the potential as water stress indicators. More experiments and analysis are needed to validate the conclusion.
Oblique Aerial Photography Tool for Building Inspection and Damage Assessment
NASA Astrophysics Data System (ADS)
Murtiyoso, A.; Remondino, F.; Rupnik, E.; Nex, F.; Grussenmeyer, P.
2014-11-01
Aerial photography has a long history of being employed for mapping purposes due to some of its main advantages, including large area imaging from above and minimization of field work. Since few years multi-camera aerial systems are becoming a practical sensor technology across a growing geospatial market, as complementary to the traditional vertical views. Multi-camera aerial systems capture not only the conventional nadir views, but also tilted images at the same time. In this paper, a particular use of such imagery in the field of building inspection as well as disaster assessment is addressed. The main idea is to inspect a building from four cardinal directions by using monoplotting functionalities. The developed application allows to measure building height and distances and to digitize man-made structures, creating 3D surfaces and building models. The realized GUI is capable of identifying a building from several oblique points of views, as well as calculates the approximate height of buildings, ground distances and basic vectorization. The geometric accuracy of the results remains a function of several parameters, namely image resolution, quality of available parameters (DEM, calibration and orientation values), user expertise and measuring capability.
Goyal, Anish; Myers, Travis; Wang, Christine A; Kelly, Michael; Tyrrell, Brian; Gokden, B; Sanchez, Antonio; Turner, George; Capasso, Federico
2014-06-16
We demonstrate active hyperspectral imaging using a quantum-cascade laser (QCL) array as the illumination source and a digital-pixel focal-plane-array (DFPA) camera as the receiver. The multi-wavelength QCL array used in this work comprises 15 individually addressable QCLs in which the beams from all lasers are spatially overlapped using wavelength beam combining (WBC). The DFPA camera was configured to integrate the laser light reflected from the sample and to perform on-chip subtraction of the passive thermal background. A 27-frame hyperspectral image was acquired of a liquid contaminant on a diffuse gold surface at a range of 5 meters. The measured spectral reflectance closely matches the calculated reflectance. Furthermore, the high-speed capabilities of the system were demonstrated by capturing differential reflectance images of sand and KClO3 particles that were moving at speeds of up to 10 m/s.
Large-area photogrammetry based testing of wind turbine blades
NASA Astrophysics Data System (ADS)
Poozesh, Peyman; Baqersad, Javad; Niezrecki, Christopher; Avitabile, Peter; Harvey, Eric; Yarala, Rahul
2017-03-01
An optically based sensing system that can measure the displacement and strain over essentially the entire area of a utility-scale blade leads to a measurement system that can significantly reduce the time and cost associated with traditional instrumentation. This paper evaluates the performance of conventional three dimensional digital image correlation (3D DIC) and three dimensional point tracking (3DPT) approaches over the surface of wind turbine blades and proposes a multi-camera measurement system using dynamic spatial data stitching. The potential advantages for the proposed approach include: (1) full-field measurement distributed over a very large area, (2) the elimination of time-consuming wiring and expensive sensors, and (3) the need for large-channel data acquisition systems. There are several challenges associated with extending the capability of a standard 3D DIC system to measure entire surface of utility scale blades to extract distributed strain, deflection, and modal parameters. This paper only tries to address some of the difficulties including: (1) assessing the accuracy of the 3D DIC system to measure full-field distributed strain and displacement over the large area, (2) understanding the geometrical constraints associated with a wind turbine testing facility (e.g. lighting, working distance, and speckle pattern size), (3) evaluating the performance of the dynamic stitching method to combine two different fields of view by extracting modal parameters from aligned point clouds, and (4) determining the feasibility of employing an output-only system identification to estimate modal parameters of a utility scale wind turbine blade from optically measured data. Within the current work, the results of an optical measurement (one stereo-vision system) performed on a large area over a 50-m utility-scale blade subjected to quasi-static and cyclic loading are presented. The blade certification and testing is typically performed using International Electro-Technical Commission standard (IEC 61400-23). For static tests, the blade is pulled in either flap-wise or edge-wise directions to measure deflection or distributed strain at a few limited locations of a large-sized blade. Additionally, the paper explores the error associated with using a multi-camera system (two stereo-vision systems) in measuring 3D displacement and extracting structural dynamic parameters on a mock set up emulating a utility-scale wind turbine blade. The results obtained in this paper reveal that the multi-camera measurement system has the potential to identify the dynamic characteristics of a very large structure.
Clouds and Ice of the Lambert-Amery System, East Antarctica
NASA Technical Reports Server (NTRS)
2002-01-01
These views from the Multi-angle Imaging SpectroRadiometer (MISR) illustrate ice surface textures and cloud-top heights over the Amery Ice Shelf/Lambert Glacier system in East Antarctica on October 25, 2002.The left-hand panel is a natural-color view from MISR's downward-looking (nadir) camera. The center panel is a multi-angular composite from three MISR cameras, in which color acts as a proxy for angular reflectance variations related to texture. Here, data from the red-band of MISR's 60o forward-viewing, nadir and 60o backward-viewing cameras are displayed as red, green and blue, respectively. With this display technique, surfaces which predominantly exhibit backward-scattering (generally rough surfaces) appear red/orange, while surfaces which predominantly exhibit forward-scattering (generally smooth surfaces) appear blue. Textural variation for both the grounded and sea ice are apparent. The red/orange pixels in the lower portion of the image correspond with a rough and crevassed region near the grounding zone, that is, the area where the Lambert and four other smaller glaciers merge and the ice starts to float as it forms the Amery Ice Shelf. In the natural-color view, this rough ice is spectrally blue in color.Clouds exhibit both forward and backward-scattering properties in the middle panel and thus appear purple, in distinct contrast with the underlying ice and snow. An additional multi-angular technique for differentiating clouds from ice is shown in the right-hand panel, which is a stereoscopically derived height field retrieved using automated pattern recognition involving data from multiple MISR cameras. Areas exhibiting insufficient spatial contrast for stereoscopic retrieval are shown in dark gray. Clouds are apparent as a result of their heights above the surface terrain. Polar clouds are an important factor in weather and climate. Inadequate characterization of cloud properties is currently responsible for large uncertainties in climate prediction models. Identification of polar clouds, mapping of their distributions, and retrieval of their heights provide information that will help to reduce this uncertainty.The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 15171. The panels cover an area of 380 kilometers x 984 kilometers, and utilize data from blocks 145 to 151 within World Reference System-2 path 127.MISR was built and is managed by NASA's Jet Propulsion Laboratory,Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center,Greenbelt, MD. JPL is a division of the California Institute of Technology.The Topographic Data Deluge - Collecting and Maintaining Data in a 21ST Century Mapping Agency
NASA Astrophysics Data System (ADS)
Holland, D. A.; Pook, C.; Capstick, D.; Hemmings, A.
2016-06-01
In the last few years, the number of sensors and data collection systems available to a mapping agency has grown considerably. In the field, in addition to total stations measuring position, angles and distances, the surveyor can choose from hand-held GPS devices, multi-lens imaging systems or laser scanners, which may be integrated with a laptop or tablet to capture topographic data directly in the field. These systems are joined by mobile mapping solutions, mounted on large or small vehicles, or sometimes even on a backpack carried by a surveyor walking around a site. Such systems allow the raw data to be collected rapidly in the field, while the interpretation of the data can be performed back in the office at a later date. In the air, large format digital cameras and airborne lidar sensors are being augmented with oblique camera systems, taking multiple views at each camera position and being used to create more realistic 3D city models. Lower down in the atmosphere, Unmanned Aerial Vehicles (or Remotely Piloted Aircraft Systems) have suddenly become ubiquitous. Hundreds of small companies have sprung up, providing images from UAVs using ever more capable consumer cameras. It is now easy to buy a 42 megapixel camera off the shelf at the local camera shop, and Canon recently announced that they are developing a 250 megapixel sensor for the consumer market. While these sensors may not yet rival the metric cameras used by today's photogrammetrists, the rapid developments in sensor technology could eventually lead to the commoditization of high-resolution camera systems. With data streaming in from so many sources, the main issue for a mapping agency is how to interpret, store and update the data in such a way as to enable the creation and maintenance of the end product. This might be a topographic map, ortho-image or a digital surface model today, but soon it is just as likely to be a 3D point cloud, textured 3D mesh, 3D city model, or Building Information Model (BIM) with all the data interpretation and modelling that entails. In this paper, we describe research/investigations into the developing technologies and outline the findings for a National Mapping Agency (NMA). We also look at the challenges that these new data collection systems will bring to an NMA, and suggest ways that we may work to meet these challenges and deliver the products desired by our users.
2002-03-03
The Hubble Space Telescope (HST), with its normal routine temporarily interrupted, is about to be captured by the Space Shuttle Columbia prior to a week of servicing and upgrading by the STS-109 crew. The telescope was captured by the shuttle's Remote Manipulator System (RMS) robotic arm and secured on a work stand in Columbia's payload bay where 4 of the 7-member crew performed 5 space walks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. Launched March 1, 2002, the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.
2003-09-08
KENNEDY SPACE CENTER, FLA. - The Window Observational Research Facility (WORF), seen in the Space Station Processing Facility, was designed and built by the Boeing Co. at NASA’s Marshall Space Flight Center in Huntsville, Ala. WORF will be delivered to the International Space Station and placed in the rack position in front of the Destiny lab window, providing locations for attaching cameras, multi-spectral scanners and other instruments. WORF will support a variety of scientific and commercial experiments in areas of Earth systems and processes, global ecological changes in Earth’s biosphere, lithosphere, hydrosphere and climate system, Earth resources, natural hazards, and education. After installation, it will become a permanent focal point for Earth Science research aboard the space station.
2003-09-08
KENNEDY SPACE CENTER, FLA. - Workers in the Space Station Processing Facility check out the Window Observational Research Facility (WORF), designed and built by the Boeing Co. at NASA’s Marshall Space Flight Center in Huntsville, Ala. WORF will be delivered to the International Space Station and placed in the rack position in front of the Destiny lab window, providing locations for attaching cameras, multi-spectral scanners and other instruments. WORF will support a variety of scientific and commercial experiments in areas of Earth systems and processes, global ecological changes in Earth’s biosphere, lithosphere, hydrosphere and climate system, Earth resources, natural hazards, and education. After installation, it will become a permanent focal point for Earth Science research aboard the space station.
A target detection multi-layer matched filter for color and hyperspectral cameras
NASA Astrophysics Data System (ADS)
Miyanishi, Tomoya; Preece, Bradley L.; Reynolds, Joseph P.
2018-05-01
In this article, a method for applying matched filters to a 3-dimentional hyperspectral data cube is discussed. In many applications, color visible cameras or hyperspectral cameras are used for target detection where the color or spectral optical properties of the imaged materials are partially known in advance. Therefore, the use of matched filtering with spectral data along with shape data is an effective method for detecting certain targets. Since many methods for 2D image filtering have been researched, we propose a multi-layer filter where ordinary spatially matched filters are used before the spectral filters. We discuss a way to layer the spectral filters for a 3D hyperspectral data cube, accompanied by a detectability metric for calculating the SNR of the filter. This method is appropriate for visible color cameras and hyperspectral cameras. We also demonstrate an analysis using the Night Vision Integrated Performance Model (NV-IPM) and a Monte Carlo simulation in order to confirm the effectiveness of the filtering in providing a higher output SNR and a lower false alarm rate.
Synchronous high speed multi-point velocity profile measurement by heterodyne interferometry
NASA Astrophysics Data System (ADS)
Hou, Xueqin; Xiao, Wen; Chen, Zonghui; Qin, Xiaodong; Pan, Feng
2017-02-01
This paper presents a synchronous multipoint velocity profile measurement system, which acquires the vibration velocities as well as images of vibrating objects by combining optical heterodyne interferometry and a high-speed CMOS-DVR camera. The high-speed CMOS-DVR camera records a sequence of images of the vibrating object. Then, by extracting and processing multiple pixels at the same time, a digital demodulation technique is implemented to simultaneously acquire the vibrating velocity of the target from the recorded sequences of images. This method is validated with an experiment. A piezoelectric ceramic plate with standard vibration characteristics is used as the vibrating target, which is driven by a standard sinusoidal signal.
Feng, Lei; Fang, Hui; Zhou, Wei-Jun; Huang, Min; He, Yong
2006-09-01
Site-specific variable nitrogen application is one of the major precision crop production management operations. Obtaining sufficient crop nitrogen stress information is essential for achieving effective site-specific nitrogen applications. The present paper describes the development of a multi-spectral nitrogen deficiency sensor, which uses three channels (green, red, near-infrared) of crop images to determine the nitrogen level of canola. This sensor assesses the nitrogen stress by means of estimated SPAD value of the canola based on canola canopy reflectance sensed using three channels (green, red, near-infrared) of the multi-spectral camera. The core of this investigation is the calibration methods between the multi-spectral references and the nitrogen levels in crops measured using a SPAD 502 chlorophyll meter. Based on the results obtained from this study, it can be concluded that a multi-spectral CCD camera can provide sufficient information to perform reasonable SPAD values estimation during field operations.
NASA Astrophysics Data System (ADS)
Drass, Holger; Vanzi, Leonardo; Torres-Torriti, Miguel; Dünner, Rolando; Shen, Tzu-Chiang; Belmar, Francisco; Dauvin, Lousie; Staig, Tomás.; Antognini, Jonathan; Flores, Mauricio; Luco, Yerko; Béchet, Clémentine; Boettger, David; Beard, Steven; Montgomery, David; Watson, Stephen; Cabral, Alexandre; Hayati, Mahmoud; Abreu, Manuel; Rees, Phil; Cirasuolo, Michele; Taylor, William; Fairley, Alasdair
2016-08-01
The Multi-Object Optical and Near-infrared Spectrograph (MOONS) will cover the Very Large Telescope's (VLT) field of view with 1000 fibres. The fibres will be mounted on fibre positioning units (FPU) implemented as two-DOF robot arms to ensure a homogeneous coverage of the 500 square arcmin field of view. To accurately and fast determine the position of the 1000 fibres a metrology system has been designed. This paper presents the hardware and software design and performance of the metrology system. The metrology system is based on the analysis of images taken by a circular array of 12 cameras located close to the VLTs derotator ring around the Nasmyth focus. The system includes 24 individually adjustable lamps. The fibre positions are measured through dedicated metrology targets mounted on top of the FPUs and fiducial markers connected to the FPU support plate which are imaged at the same time. A flexible pipeline based on VLT standards is used to process the images. The position accuracy was determined to 5 μm in the central region of the images. Including the outer regions the overall positioning accuracy is 25 μm. The MOONS metrology system is fully set up with a working prototype. The results in parts of the images are already excellent. By using upcoming hardware and improving the calibration it is expected to fulfil the accuracy requirement over the complete field of view for all metrology cameras.
2002-03-08
After five days of service and upgrade work on the Hubble Space Telescope (HST), the STS-109 crew photographed the giant telescope in the shuttle's cargo bay. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where 4 of the 7-member crew performed 5 space walks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. Launched March 1, 2002, the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.
2002-03-07
Inside the Space Shuttle Columbia's cabin, astronaut Nancy J. Currie, mission specialist, controlled the Remote Manipulator System (RMS) on the crew cabin's aft flight deck to assist fellow astronauts during the STS-109 mission Extra Vehicular Activities (EVA). The RMS was used to capture the telescope and secure it into Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.
2002-03-09
After five days of service and upgrade work on the Hubble Space Telescope (HST), the STS-109 crew photographed the giant telescope returning to its normal routine. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where 4 of the 7-member crew performed 5 space walks completing system upgrades to the HST. Included in those upgrades were: The replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near- Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. Launched March 1, 2002, the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.
Extended depth of field integral imaging using multi-focus fusion
NASA Astrophysics Data System (ADS)
Piao, Yongri; Zhang, Miao; Wang, Xiaohui; Li, Peihua
2018-03-01
In this paper, we propose a new method for depth of field extension in integral imaging by realizing the image fusion method on the multi-focus elemental images. In the proposed method, a camera is translated on a 2D grid to take multi-focus elemental images by sweeping the focus plane across the scene. Simply applying an image fusion method on the elemental images holding rich parallax information does not work effectively because registration accuracy of images is the prerequisite for image fusion. To solve this problem an elemental image generalization method is proposed. The aim of this generalization process is to geometrically align the objects in all elemental images so that the correct regions of multi-focus elemental images can be exacted. The all-in focus elemental images are then generated by fusing the generalized elemental images using the block based fusion method. The experimental results demonstrate that the depth of field of synthetic aperture integral imaging system has been extended by realizing the generation method combined with the image fusion on multi-focus elemental images in synthetic aperture integral imaging system.
Mary, a Pipeline to Aid Discovery of Optical Transients
NASA Astrophysics Data System (ADS)
Andreoni, I.; Jacobs, C.; Hegarty, S.; Pritchard, T.; Cooke, J.; Ryder, S.
2017-09-01
The ability to quickly detect transient sources in optical images and trigger multi-wavelength follow up is key for the discovery of fast transients. These include events rare and difficult to detect such as kilonovae, supernova shock breakout, and `orphan' Gamma-ray Burst afterglows. We present the Mary pipeline, a (mostly) automated tool to discover transients during high-cadenced observations with the Dark Energy Camera at Cerro Tololo Inter-American Observatory (CTIO). The observations are part of the `Deeper Wider Faster' programme, a multi-facility, multi-wavelength programme designed to discover fast transients, including counterparts to Fast Radio Bursts and gravitational waves. Our tests of the Mary pipeline on Dark Energy Camera images return a false positive rate of 2.2% and a missed fraction of 3.4% obtained in less than 2 min, which proves the pipeline to be suitable for rapid and high-quality transient searches. The pipeline can be adapted to search for transients in data obtained with imagers other than Dark Energy Camera.
NASA Astrophysics Data System (ADS)
Swain, Pradyumna; Mark, David
2004-09-01
The emergence of curved CCD detectors as individual devices or as contoured mosaics assembled to match the curved focal planes of astronomical telescopes and terrestrial stereo panoramic cameras represents a major optical design advancement that greatly enhances the scientific potential of such instruments. In altering the primary detection surface within the telescope"s optical instrumentation system from flat to curved, and conforming the applied CCD"s shape precisely to the contour of the telescope"s curved focal plane, a major increase in the amount of transmittable light at various wavelengths through the system is achieved. This in turn enables multi-spectral ultra-sensitive imaging with much greater spatial resolution necessary for large and very large telescope applications, including those involving infrared image acquisition and spectroscopy, conducted over very wide fields of view. For earth-based and space-borne optical telescopes, the advent of curved CCD"s as the principle detectors provides a simplification of the telescope"s adjoining optics, reducing the number of optical elements and the occurrence of optical aberrations associated with large corrective optics used to conform to flat detectors. New astronomical experiments may be devised in the presence of curved CCD applications, in conjunction with large format cameras and curved mosaics, including three dimensional imaging spectroscopy conducted over multiple wavelengths simultaneously, wide field real-time stereoscopic tracking of remote objects within the solar system at high resolution, and deep field survey mapping of distant objects such as galaxies with much greater multi-band spatial precision over larger sky regions. Terrestrial stereo panoramic cameras equipped with arrays of curved CCD"s joined with associative wide field optics will require less optical glass and no mechanically moving parts to maintain continuous proper stereo convergence over wider perspective viewing fields than their flat CCD counterparts, lightening the cameras and enabling faster scanning and 3D integration of objects moving within a planetary terrain environment. Preliminary experiments conducted at the Sarnoff Corporation indicate the feasibility of curved CCD imagers with acceptable electro-optic integrity. Currently, we are in the process of evaluating the electro-optic performance of a curved wafer scale CCD imager. Detailed ray trace modeling and experimental electro-optical data performance obtained from the curved imager will be presented at the conference.
Long-term monitoring on environmental disasters using multi-source remote sensing technique
NASA Astrophysics Data System (ADS)
Kuo, Y. C.; Chen, C. F.
2017-12-01
Environmental disasters are extreme events within the earth's system that cause deaths and injuries to humans, as well as causing damages and losses of valuable assets, such as buildings, communication systems, farmlands, forest and etc. In disaster management, a large amount of multi-temporal spatial data is required. Multi-source remote sensing data with different spatial, spectral and temporal resolutions is widely applied on environmental disaster monitoring. With multi-source and multi-temporal high resolution images, we conduct rapid, systematic and seriate observations regarding to economic damages and environmental disasters on earth. It is based on three monitoring platforms: remote sensing, UAS (Unmanned Aircraft Systems) and ground investigation. The advantages of using UAS technology include great mobility and availability in real-time rapid and more flexible weather conditions. The system can produce long-term spatial distribution information from environmental disasters, obtaining high-resolution remote sensing data and field verification data in key monitoring areas. It also supports the prevention and control on ocean pollutions, illegally disposed wastes and pine pests in different scales. Meanwhile, digital photogrammetry can be applied on the camera inside and outside the position parameters to produce Digital Surface Model (DSM) data. The latest terrain environment information is simulated by using DSM data, and can be used as references in disaster recovery in the future.
Thermal Imaging of Flame in Air-assisted Atomizer for Burner System
NASA Astrophysics Data System (ADS)
Amirnordin, S. H.; Khalid, Amir; Zailan, M. F.; Fawzi, Mas; Salleh, Hamidon; Zaman, Izzuddin
2017-08-01
Infrared thermography was used as a part of non-intrusion technique on the flame temperature analysis. This paper demonstrates the technique to generate the thermal images of flame from the air-assisted atomizer. The multi-circular jet plate acts as a turbulence generator to improve the fuel and air mixing in the atomizer. Three types of multi-circular jet plate geometry were analysed at different equivalence ratio. Thermal infrared imaging using FLIR thermal camera were used to obtain the flame temperature. Multi-circular jet 1 shows the highest flame temperature obtained compared to other plates. It can be concluded that the geometry of the plate influences the combustion, hence affects the flame temperature profile from the air-assisted atomizer.
NASA Astrophysics Data System (ADS)
Piermattei, Livia; Bozzi, Carlo Alberto; Mancini, Adriano; Tassetti, Anna Nora; Karel, Wilfried; Pfeifer, Norbert
2017-04-01
Unmanned aerial vehicles (UAVs) in combination with consumer grade cameras have become standard tools for photogrammetric applications and surveying. The recent generation of multispectral, cost-efficient and lightweight cameras has fostered a breakthrough in the practical application of UAVs for precision agriculture. For this application, multispectral cameras typically use Green, Red, Red-Edge (RE) and Near Infrared (NIR) wavebands to capture both visible and invisible images of crops and vegetation. These bands are very effective for deriving characteristics like soil productivity, plant health and overall growth. However, the quality of results is affected by the sensor architecture, the spatial and spectral resolutions, the pattern of image collection, and the processing of the multispectral images. In particular, collecting data with multiple sensors requires an accurate spatial co-registration of the various UAV image datasets. Multispectral processed data in precision agriculture are mainly presented as orthorectified mosaics used to export information maps and vegetation indices. This work aims to investigate the acquisition parameters and processing approaches of this new type of image data in order to generate orthoimages using different sensors and UAV platforms. Within our experimental area we placed a grid of artificial targets, whose position was determined with differential global positioning system (dGPS) measurements. Targets were used as ground control points to georeference the images and as checkpoints to verify the accuracy of the georeferenced mosaics. The primary aim is to present a method for the spatial co-registration of visible, Red-Edge, and NIR image sets. To demonstrate the applicability and accuracy of our methodology, multi-sensor datasets were collected over the same area and approximately at the same time using the fixed-wing UAV senseFly "eBee". The images were acquired with the camera Canon S110 RGB, the multispectral cameras Canon S110 NIR and S110 RE and with the multi-camera system Parrot Sequoia, which is composed of single-band cameras (Green, Red, Red Edge, NIR and RGB). Imagery from each sensor was georeferenced and mosaicked with the commercial software Agisoft PhotoScan Pro and different approaches for image orientation were compared. To assess the overall spatial accuracy of each dataset the root mean square error was computed between check point coordinates measured with dGPS and coordinates retrieved from georeferenced image mosaics. Additionally, image datasets from different UAV platforms (i.e. DJI Phantom 4Pro, DJI Phantom 3 professional, and DJI Inspire 1 Pro) were acquired over the same area and the spatial accuracy of the orthoimages was evaluated.
A complete system for 3D reconstruction of roots for phenotypic analysis.
Kumar, Pankaj; Cai, Jinhai; Miklavcic, Stanley J
2015-01-01
Here we present a complete system for 3D reconstruction of roots grown in a transparent gel medium or washed and suspended in water. The system is capable of being fully automated as it is self calibrating. The system starts with detection of root tips in root images from an image sequence generated by a turntable motion. Root tips are detected using the statistics of Zernike moments on image patches centred on high curvature points on root boundary and Bayes classification rule. The detected root tips are tracked in the image sequence using a multi-target tracking algorithm. Conics are fitted to the root tip trajectories using a novel ellipse fitting algorithm which weighs the data points by its eccentricity. The conics projected from the circular trajectory have a complex conjugate intersection which are image of the circular points. Circular points constraint the image of the absolute conics which are directly related to the internal parameters of the camera. The pose of the camera is computed from the image of the rotation axis and the horizon. The silhouettes of the roots and camera parameters are used to reconstruction the 3D voxel model of the roots. We show the results of real 3D reconstruction of roots which are detailed and realistic for phenotypic analysis.
Design and performance tests of the calorimetric tract of a Compton Camera for small-animals imaging
NASA Astrophysics Data System (ADS)
Rossi, P.; Baldazzi, G.; Battistella, A.; Bello, M.; Bollini, D.; Bonvicini, V.; Fontana, C. L.; Gennaro, G.; Moschini, G.; Navarria, F.; Rashevsky, A.; Uzunov, N.; Zampa, G.; Zampa, N.; Vacchi, A.
2011-02-01
The bio-distribution and targeting capability of pharmaceuticals may be assessed in small animals by imaging gamma-rays emitted from radio-isotope markers. Detectors that exploit the Compton concept allow higher gamma-ray efficiency compared to conventional Anger cameras employing collimators, and feature sub-millimeter spatial resolution and compact geometry. We are developing a Compton Camera that has to address several requirements: the high rates typical of the Compton concept; detection of gamma-rays of different energies that may range from 140 keV ( 99 mTc) to 511 keV ( β+ emitters); presence of gamma and beta radiation with energies up to 2 MeV in case of 188Re. The camera consists of a thin position-sensitive Tracker that scatters the gamma ray, and a second position-sensitive detection system to totally absorb the energy of the scattered photons (Calorimeter). In this paper we present the design and discuss the realization of the calorimetric tract, including the choice of scintillator crystal, pixel size, and detector geometry. Simulations of the gamma-ray trajectories from source to detectors have helped to assess the accuracy of the system and decide on camera design. Crystals of different materials, such as LaBr 3 GSO and YAP, and of different size, in continuous or segmented geometry, have been optically coupled to a multi-anode Hamamatsu H8500 detector, allowing measurements of spatial resolution and efficiency.
2002-01-22
KENNEDY SPACE CENTER, FLA. -- Workers in the Vertical Processing Facility oversee the installation of the NICMOS radiator onto the MULE (Multi-Use Lightweight Equipment) carrier. Part of the payload on mission STS-109, the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. NICMOS could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of Columbia on mission STS-109 is scheduled Feb. 28, 2002
Cooperative Monocular-Based SLAM for Multi-UAV Systems in GPS-Denied Environments †
Guerra, Edmundo
2018-01-01
This work presents a cooperative monocular-based SLAM approach for multi-UAV systems that can operate in GPS-denied environments. The main contribution of the work is to show that, using visual information obtained from monocular cameras mounted onboard aerial vehicles flying in formation, the observability properties of the whole system are improved. This fact is especially notorious when compared with other related visual SLAM configurations. In order to improve the observability properties, some measurements of the relative distance between the UAVs are included in the system. These relative distances are also obtained from visual information. The proposed approach is theoretically validated by means of a nonlinear observability analysis. Furthermore, an extensive set of computer simulations is presented in order to validate the proposed approach. The numerical simulation results show that the proposed system is able to provide a good position and orientation estimation of the aerial vehicles flying in formation. PMID:29701722
Cooperative Monocular-Based SLAM for Multi-UAV Systems in GPS-Denied Environments.
Trujillo, Juan-Carlos; Munguia, Rodrigo; Guerra, Edmundo; Grau, Antoni
2018-04-26
This work presents a cooperative monocular-based SLAM approach for multi-UAV systems that can operate in GPS-denied environments. The main contribution of the work is to show that, using visual information obtained from monocular cameras mounted onboard aerial vehicles flying in formation, the observability properties of the whole system are improved. This fact is especially notorious when compared with other related visual SLAM configurations. In order to improve the observability properties, some measurements of the relative distance between the UAVs are included in the system. These relative distances are also obtained from visual information. The proposed approach is theoretically validated by means of a nonlinear observability analysis. Furthermore, an extensive set of computer simulations is presented in order to validate the proposed approach. The numerical simulation results show that the proposed system is able to provide a good position and orientation estimation of the aerial vehicles flying in formation.
Multi-MGy Radiation Hardened Camera for Nuclear Facilities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Girard, Sylvain; Boukenter, Aziz; Ouerdane, Youcef
There is an increasing interest in developing cameras for surveillance systems to monitor nuclear facilities or nuclear waste storages. Particularly, for today's and the next generation of nuclear facilities increasing safety requirements consecutive to Fukushima Daiichi's disaster have to be considered. For some applications, radiation tolerance needs to overcome doses in the MGy(SiO{sub 2}) range whereas the most tolerant commercial or prototypes products based on solid state image sensors withstand doses up to few kGy. The objective of this work is to present the radiation hardening strategy developed by our research groups to enhance the tolerance to ionizing radiations ofmore » the various subparts of these imaging systems by working simultaneously at the component and system design levels. Developing radiation-hardened camera implies to combine several radiation-hardening strategies. In our case, we decided not to use the simplest one, the shielding approach. This approach is efficient but limits the camera miniaturization and is not compatible with its future integration in remote-handling or robotic systems. Then, the hardening-by-component strategy appears mandatory to avoid the failure of one of the camera subparts at doses lower than the MGy. Concerning the image sensor itself, the used technology is a CMOS Image Sensor (CIS) designed by ISAE team with custom pixel designs used to mitigate the total ionizing dose (TID) effects that occur well below the MGy range in classical image sensors (e.g. Charge Coupled Devices (CCD), Charge Injection Devices (CID) and classical Active Pixel Sensors (APS)), such as the complete loss of functionality, the dark current increase and the gain drop. We'll present at the conference a comparative study between these radiation-hardened pixel radiation responses with respect to conventional ones, demonstrating the efficiency of the choices made. The targeted strategy to develop the complete radiation hard camera electronics will be exposed. Another important element of the camera is the optical system that transports the image from the scene to the image sensor. This arrangement of glass-based lenses is affected by radiations through two mechanisms: the radiation induced absorption and the radiation induced refractive index changes. The first one will limit the signal to noise ratio of the image whereas the second one will directly affect the resolution of the camera. We'll present at the conference a coupled simulation/experiment study of these effects for various commercial glasses and present vulnerability study of typical optical systems to radiations at MGy doses. The last very important part of the camera is the illumination system that can be based on various technologies of emitting devices like LED, SLED or lasers. The most promising solutions for high radiation doses will be presented at the conference. In addition to this hardening-by-component approach, the global radiation tolerance of the camera can be drastically improve by working at the system level, combining innovative approaches eg. for the optical and illumination systems. We'll present at the conference the developed approach allowing to extend the camera lifetime up to the MGy dose range. (authors)« less
Real-time millimeter-wave imaging radiometer for avionic synthetic vision
NASA Astrophysics Data System (ADS)
Lovberg, John A.; Chou, Ri-Chee; Martin, Christopher A.
1994-07-01
ThermoTrex Corporation (TTC) has developed an imaging radiometer, the passive microwave camera (PMC), that uses an array of frequency-scanned antennas coupled to a multi-channel acousto-optic (Bragg cell) spectrum analyzer to form visible images of a scene through acquisition of thermal blackbody radiation in the millimeter-wave spectrum. The output of the Bragg cell is imaged by a standard video camera and passed to a computer for normalization and display at real-time frame rates. One application of this system could be its incorporation into an enhanced vision system to provide pilots with a clear view of the runway during fog and other adverse weather conditions. The unique PMC system architecture will allow compact large-aperture implementations because of its flat antenna sensor. Other potential applications include air traffic control, all-weather area surveillance, fire detection, and security. This paper describes the architecture of the TTC PMC and shows examples of images acquired with the system.
Control and automation of the Pegasus multi-point Thomson scattering system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bodner, G. M., E-mail: gbodner@wisc.edu; Bongard, M. W.; Fonck, R. J.
A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. Additionally, the system has been upgraded with a set of fast (∼1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.
Control and automation of the Pegasus multi-point Thomson scattering system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bodner, Grant M.; Bongard, Michael W.; Fonck, Raymond J.
A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. In addition, the system has been upgraded with a set of fast (~1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.
Control and automation of the Pegasus multi-point Thomson scattering system
Bodner, Grant M.; Bongard, Michael W.; Fonck, Raymond J.; ...
2016-08-12
A new control system for the Pegasus Thomson scattering diagnostic has recently been deployed to automate the laser operation, data collection process, and interface with the system-wide Pegasus control code. Automation has been extended to areas outside of data collection, such as manipulation of beamline cameras and remotely controlled turning mirror actuators to enable intra-shot beam alignment. In addition, the system has been upgraded with a set of fast (~1 ms) mechanical shutters to mitigate contamination from background light. Modification and automation of the Thomson system have improved both data quality and diagnostic reliability.
A Photogrammetric System for Model Attitude Measurement in Hypersonic Wind Tunnels
NASA Technical Reports Server (NTRS)
Jones, Thomas W.; Lunsford, Charles B.
2007-01-01
A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and photogrammetric principles for point tracking to compute model position including pitch, roll and yaw. A discussion of the constraints encountered during the design, and a review of the measurement results obtained from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.
Fisheye camera around view monitoring system
NASA Astrophysics Data System (ADS)
Feng, Cong; Ma, Xinjun; Li, Yuanyuan; Wu, Chenchen
2018-04-01
360 degree around view monitoring system is the key technology of the advanced driver assistance system, which is used to assist the driver to clear the blind area, and has high application value. In this paper, we study the transformation relationship between multi coordinate system to generate panoramic image in the unified car coordinate system. Firstly, the panoramic image is divided into four regions. By using the parameters obtained by calibration, four fisheye images pixel corresponding to the four sub regions are mapped to the constructed panoramic image. On the basis of 2D around view monitoring system, 3D version is realized by reconstructing the projection surface. Then, we compare 2D around view scheme and 3D around view scheme in unified coordinate system, 3D around view scheme solves the shortcomings of the traditional 2D scheme, such as small visual field, prominent ground object deformation and so on. Finally, the image collected by a fisheye camera installed around the car body can be spliced into a 360 degree panoramic image. So it has very high application value.
NASA Astrophysics Data System (ADS)
Kishimoto, A.; Kataoka, J.; Nishiyama, T.; Fujita, T.; Takeuchi, K.; Okochi, H.; Ogata, H.; Kuroshima, H.; Ohsuka, S.; Nakamura, S.; Hirayanagi, M.; Adachi, S.; Uchiyama, T.; Suzuki, H.
2014-11-01
After the nuclear disaster in Fukushima, radiation decontamination has become particularly urgent. To help identify radiation hotspots and ensure effective decontamination operation, we have developed a novel Compton camera based on Ce-doped Gd3Al2Ga3O12 scintillators and multi-pixel photon counter (MPPC) arrays. Even though its sensitivity is several times better than that of other cameras being tested in Fukushima, we introduce a depth-of-interaction (DOI) method to further improve the angular resolution. For gamma rays, the DOI information, in addition to 2-D position, is obtained by measuring the pulse-height ratio of the MPPC arrays coupled to ends of the scintillator. We present the detailed performance and results of various field tests conducted in Fukushima with the prototype 2-D and DOI Compton cameras. Moreover, we demonstrate stereo measurement of gamma rays that enables measurement of not only direction but also approximate distance to radioactive hotspots.
Design of tangential multi-energy soft x-ray camera for NSTX-U
NASA Astrophysics Data System (ADS)
Delgado-Aparicio, Luis F.; Maddox, J.; Pablant, N.; Hill, K.; Bitter, M.; Stratton, B.; Efthimion, Phillip
2016-10-01
For tokamaks and future facilities to operate safely in a high-pressure long-pulse discharge, it is imperative to address key issues associated with impurity sources, core transport and high-Z impurity accumulation. Multi-energy SXR imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (Te, nZ and ΔZeff). A new tangential multi-energy soft x-ray pin-hole camera is being design to sample the continuum- and line-emission from low-, medium- and high-Z impurities. This new x-ray diagnostic will be installed on an equatorial midplane port of NSTX-U tokamak and will measure the radial structure of the photon emissivity with a radial resolution below 1 cm at a 500 Hz frame rate and a photon-energy resolution of 500 eV. The layout and response expected of the new system will be shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation is also addressed. This effort is designed to contribute to the near- and long-term highest priority research goals for NSTX-U which will integrate a non-inductive operation at reduced collisionality, long energy-confinement-times and a transition to a divertor solution with metal walls.
CMOS Imaging Sensor Technology for Aerial Mapping Cameras
NASA Astrophysics Data System (ADS)
Neumann, Klaus; Welzenbach, Martin; Timm, Martin
2016-06-01
In June 2015 Leica Geosystems launched the first large format aerial mapping camera using CMOS sensor technology, the Leica DMC III. This paper describes the motivation to change from CCD sensor technology to CMOS for the development of this new aerial mapping camera. In 2002 the DMC first generation was developed by Z/I Imaging. It was the first large format digital frame sensor designed for mapping applications. In 2009 Z/I Imaging designed the DMC II which was the first digital aerial mapping camera using a single ultra large CCD sensor to avoid stitching of smaller CCDs. The DMC III is now the third generation of large format frame sensor developed by Z/I Imaging and Leica Geosystems for the DMC camera family. It is an evolution of the DMC II using the same system design with one large monolithic PAN sensor and four multi spectral camera heads for R,G, B and NIR. For the first time a 391 Megapixel large CMOS sensor had been used as PAN chromatic sensor, which is an industry record. Along with CMOS technology goes a range of technical benefits. The dynamic range of the CMOS sensor is approx. twice the range of a comparable CCD sensor and the signal to noise ratio is significantly better than with CCDs. Finally results from the first DMC III customer installations and test flights will be presented and compared with other CCD based aerial sensors.
Li, Tian-Jiao; Li, Sai; Yuan, Yuan; Liu, Yu-Dong; Xu, Chuan-Long; Shuai, Yong; Tan, He-Ping
2017-04-03
Plenoptic cameras are used for capturing flames in studies of high-temperature phenomena. However, simulations of plenoptic camera models can be used prior to the experiment improve experimental efficiency and reduce cost. In this work, microlens arrays, which are based on the established light field camera model, are optimized into a hexagonal structure with three types of microlenses. With this improved plenoptic camera model, light field imaging of static objects and flame are simulated using the calibrated parameters of the Raytrix camera (R29). The optimized models improve the image resolution, imaging screen utilization, and shooting range of depth of field.
Solid-state framing camera with multiple time frames
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baker, K. L.; Stewart, R. E.; Steele, P. T.
2013-10-07
A high speed solid-state framing camera has been developed which can operate over a wide range of photon energies. This camera measures the two-dimensional spatial profile of the flux incident on a cadmium selenide semiconductor at multiple times. This multi-frame camera has been tested at 3.1 eV and 4.5 keV. The framing camera currently records two frames with a temporal separation between the frames of 5 ps but this separation can be varied between hundreds of femtoseconds up to nanoseconds and the number of frames can be increased by angularly multiplexing the probe beam onto the cadmium selenide semiconductor.
Multi-camera real-time three-dimensional tracking of multiple flying animals
Straw, Andrew D.; Branson, Kristin; Neumann, Titus R.; Dickinson, Michael H.
2011-01-01
Automated tracking of animal movement allows analyses that would not otherwise be possible by providing great quantities of data. The additional capability of tracking in real time—with minimal latency—opens up the experimental possibility of manipulating sensory feedback, thus allowing detailed explorations of the neural basis for control of behaviour. Here, we describe a system capable of tracking the three-dimensional position and body orientation of animals such as flies and birds. The system operates with less than 40 ms latency and can track multiple animals simultaneously. To achieve these results, a multi-target tracking algorithm was developed based on the extended Kalman filter and the nearest neighbour standard filter data association algorithm. In one implementation, an 11-camera system is capable of tracking three flies simultaneously at 60 frames per second using a gigabit network of nine standard Intel Pentium 4 and Core 2 Duo computers. This manuscript presents the rationale and details of the algorithms employed and shows three implementations of the system. An experiment was performed using the tracking system to measure the effect of visual contrast on the flight speed of Drosophila melanogaster. At low contrasts, speed is more variable and faster on average than at high contrasts. Thus, the system is already a useful tool to study the neurobiology and behaviour of freely flying animals. If combined with other techniques, such as ‘virtual reality’-type computer graphics or genetic manipulation, the tracking system would offer a powerful new way to investigate the biology of flying animals. PMID:20630879
Chavez-Burbano, Patricia; Rabadan, Jose; Perez-Jimenez, Rafael
2017-01-01
Due to the massive insertion of embedded cameras in a wide variety of devices and the generalized use of LED lamps, Optical Camera Communication (OCC) has been proposed as a practical solution for future Internet of Things (IoT) and smart cities applications. Influence of mobility, weather conditions, solar radiation interference, and external light sources over Visible Light Communication (VLC) schemes have been addressed in previous works. Some authors have studied the spatial intersymbol interference from close emitters within an OCC system; however, it has not been characterized or measured in function of the different transmitted wavelengths. In this work, this interference has been experimentally characterized and the Normalized Power Signal to Interference Ratio (NPSIR) for easily determining the interference in other implementations, independently of the selected system devices, has been also proposed. A set of experiments in a darkroom, working with RGB multi-LED transmitters and a general purpose camera, were performed in order to obtain the NPSIR values and to validate the deduced equations for 2D pixel representation of real distances. These parameters were used in the simulation of a wireless sensor network scenario in a small office, where the Bit Error Rate (BER) of the communication link was calculated. The experiments show that the interference of other close emitters in terms of the distance and the used wavelength can be easily determined with the NPSIR. Finally, the simulation validates the applicability of the deduced equations for scaling the initial results into real scenarios. PMID:28677613
Chavez-Burbano, Patricia; Guerra, Victor; Rabadan, Jose; Rodríguez-Esparragón, Dionisio; Perez-Jimenez, Rafael
2017-07-04
Due to the massive insertion of embedded cameras in a wide variety of devices and the generalized use of LED lamps, Optical Camera Communication (OCC) has been proposed as a practical solution for future Internet of Things (IoT) and smart cities applications. Influence of mobility, weather conditions, solar radiation interference, and external light sources over Visible Light Communication (VLC) schemes have been addressed in previous works. Some authors have studied the spatial intersymbol interference from close emitters within an OCC system; however, it has not been characterized or measured in function of the different transmitted wavelengths. In this work, this interference has been experimentally characterized and the Normalized Power Signal to Interference Ratio (NPSIR) for easily determining the interference in other implementations, independently of the selected system devices, has been also proposed. A set of experiments in a darkroom, working with RGB multi-LED transmitters and a general purpose camera, were performed in order to obtain the NPSIR values and to validate the deduced equations for 2D pixel representation of real distances. These parameters were used in the simulation of a wireless sensor network scenario in a small office, where the Bit Error Rate (BER) of the communication link was calculated. The experiments show that the interference of other close emitters in terms of the distance and the used wavelength can be easily determined with the NPSIR. Finally, the simulation validates the applicability of the deduced equations for scaling the initial results into real scenarios.
Geiger-mode APD camera system for single-photon 3D LADAR imaging
NASA Astrophysics Data System (ADS)
Entwistle, Mark; Itzler, Mark A.; Chen, Jim; Owens, Mark; Patel, Ketan; Jiang, Xudong; Slomkowski, Krystyna; Rangwala, Sabbir
2012-06-01
The unparalleled sensitivity of 3D LADAR imaging sensors based on single photon detection provides substantial benefits for imaging at long stand-off distances and minimizing laser pulse energy requirements. To obtain 3D LADAR images with single photon sensitivity, we have demonstrated focal plane arrays (FPAs) based on InGaAsP Geiger-mode avalanche photodiodes (GmAPDs) optimized for use at either 1.06 μm or 1.55 μm. These state-of-the-art FPAs exhibit excellent pixel-level performance and the capability for 100% pixel yield on a 32 x 32 format. To realize the full potential of these FPAs, we have recently developed an integrated camera system providing turnkey operation based on FPGA control. This system implementation enables the extremely high frame-rate capability of the GmAPD FPA, and frame rates in excess of 250 kHz (for 0.4 μs range gates) can be accommodated using an industry-standard CameraLink interface in full configuration. Real-time data streaming for continuous acquisition of 2 μs range gate point cloud data with 13-bit time-stamp resolution at 186 kHz frame rates has been established using multiple solid-state storage drives. Range gate durations spanning 4 ns to 10 μs provide broad operational flexibility. The camera also provides real-time signal processing in the form of multi-frame gray-scale contrast images and single-frame time-stamp histograms, and automated bias control has been implemented to maintain a constant photon detection efficiency in the presence of ambient temperature changes. A comprehensive graphical user interface has been developed to provide complete camera control using a simple serial command set, and this command set supports highly flexible end-user customization.
Multi-Purpose Crew Vehicle Camera Asset Planning: Imagery Previsualization
NASA Technical Reports Server (NTRS)
Beaulieu, K.
2014-01-01
Using JSC-developed and other industry-standard off-the-shelf 3D modeling, animation, and rendering software packages, the Image Science Analysis Group (ISAG) supports Orion Project imagery planning efforts through dynamic 3D simulation and realistic previsualization of ground-, vehicle-, and air-based camera output.
High-speed imaging using 3CCD camera and multi-color LED flashes
NASA Astrophysics Data System (ADS)
Hijazi, Ala; Friedl, Alexander; Cierpka, Christian; Kähler, Christian; Madhavan, Vis
2017-11-01
This paper demonstrates the possibility of capturing full-resolution, high-speed image sequences using a regular 3CCD color camera in conjunction with high-power light emitting diodes of three different colors. This is achieved using a novel approach, referred to as spectral-shuttering, where a high-speed image sequence is captured using short duration light pulses of different colors that are sent consecutively in very close succession. The work presented in this paper demonstrates the feasibility of configuring a high-speed camera system using low cost and readily available off-the-shelf components. This camera can be used for recording six-frame sequences at frame rates up to 20 kHz or three-frame sequences at even higher frame rates. Both color crosstalk and spatial matching between the different channels of the camera are found to be within acceptable limits. A small amount of magnification difference between the different channels is found and a simple calibration procedure for correcting the images is introduced. The images captured using the approach described here are of good quality to be used for obtaining full-field quantitative information using techniques such as digital image correlation and particle image velocimetry. A sequence of six high-speed images of a bubble splash recorded at 400 Hz is presented as a demonstration.
Cloud Forecasting and 3-D Radiative Transfer Model Validation using Citizen-Sourced Imagery
NASA Astrophysics Data System (ADS)
Gasiewski, A. J.; Heymsfield, A.; Newman Frey, K.; Davis, R.; Rapp, J.; Bansemer, A.; Coon, T.; Folsom, R.; Pfeufer, N.; Kalloor, J.
2017-12-01
Cloud radiative feedback mechanisms are one of the largest sources of uncertainty in global climate models. Variations in local 3D cloud structure impact the interpretation of NASA CERES and MODIS data for top-of-atmosphere radiation studies over clouds. Much of this uncertainty results from lack of knowledge of cloud vertical and horizontal structure. Surface-based data on 3-D cloud structure from a multi-sensor array of low-latency ground-based cameras can be used to intercompare radiative transfer models based on MODIS and other satellite data with CERES data to improve the 3-D cloud parameterizations. Closely related, forecasting of solar insolation and associated cloud cover on time scales out to 1 hour and with spatial resolution of 100 meters is valuable for stabilizing power grids with high solar photovoltaic penetrations. Data for cloud-advection based solar insolation forecasting with requisite spatial resolution and latency needed to predict high ramp rate events obtained from a bottom-up perspective is strongly correlated with cloud-induced fluctuations. The development of grid management practices for improved integration of renewable solar energy thus also benefits from a multi-sensor camera array. The data needs for both 3D cloud radiation modelling and solar forecasting are being addressed using a network of low-cost upward-looking visible light CCD sky cameras positioned at 2 km spacing over an area of 30-60 km in size acquiring imagery on 30 second intervals. Such cameras can be manufactured in quantity and deployed by citizen volunteers at a marginal cost of 200-400 and operated unattended using existing communications infrastructure. A trial phase to understand the potential utility of up-looking multi-sensor visible imagery is underway within this NASA Citizen Science project. To develop the initial data sets necessary to optimally design a multi-sensor cloud camera array a team of 100 citizen scientists using self-owned PDA cameras is being organized to collect distributed cloud data sets suitable for MODIS-CERES cloud radiation science and solar forecasting algorithm development. A low-cost and robust sensor design suitable for large scale fabrication and long term deployment has been developed during the project prototyping phase.
The 3-D image recognition based on fuzzy neural network technology
NASA Technical Reports Server (NTRS)
Hirota, Kaoru; Yamauchi, Kenichi; Murakami, Jun; Tanaka, Kei
1993-01-01
Three dimensional stereoscopic image recognition system based on fuzzy-neural network technology was developed. The system consists of three parts; preprocessing part, feature extraction part, and matching part. Two CCD color camera image are fed to the preprocessing part, where several operations including RGB-HSV transformation are done. A multi-layer perception is used for the line detection in the feature extraction part. Then fuzzy matching technique is introduced in the matching part. The system is realized on SUN spark station and special image input hardware system. An experimental result on bottle images is also presented.
NASA Astrophysics Data System (ADS)
Gouverneur, B.; Verstockt, S.; Pauwels, E.; Han, J.; de Zeeuw, P. M.; Vermeiren, J.
2012-10-01
Various visible and infrared cameras have been tested for the early detection of wildfires to protect archeological treasures. This analysis was possible thanks to the EU Firesense project (FP7-244088). Although visible cameras are low cost and give good results during daytime for smoke detection, they fall short under bad visibility conditions. In order to improve the fire detection probability and reduce the false alarms, several infrared bands are tested ranging from the NIR to the LWIR. The SWIR and the LWIR band are helpful to locate the fire through smoke if there is a direct Line Of Sight. The Emphasis is also put on the physical and the electro-optical system modeling for forest fire detection at short and longer ranges. The fusion in three bands (Visible, SWIR, LWIR) is discussed at the pixel level for image enhancement and for fire detection.
Multithreaded hybrid feature tracking for markerless augmented reality.
Lee, Taehee; Höllerer, Tobias
2009-01-01
We describe a novel markerless camera tracking approach and user interaction methodology for augmented reality (AR) on unprepared tabletop environments. We propose a real-time system architecture that combines two types of feature tracking. Distinctive image features of the scene are detected and tracked frame-to-frame by computing optical flow. In order to achieve real-time performance, multiple operations are processed in a synchronized multi-threaded manner: capturing a video frame, tracking features using optical flow, detecting distinctive invariant features, and rendering an output frame. We also introduce user interaction methodology for establishing a global coordinate system and for placing virtual objects in the AR environment by tracking a user's outstretched hand and estimating a camera pose relative to it. We evaluate the speed and accuracy of our hybrid feature tracking approach, and demonstrate a proof-of-concept application for enabling AR in unprepared tabletop environments, using bare hands for interaction.
NASA Astrophysics Data System (ADS)
Migiyama, Go; Sugimura, Atsuhiko; Osa, Atsushi; Miike, Hidetoshi
Recently, digital cameras are offering technical advantages rapidly. However, the shot image is different from the sight image generated when that scenery is seen with the naked eye. There are blown-out highlights and crushed blacks in the image that photographed the scenery of wide dynamic range. The problems are hardly generated in the sight image. These are contributory cause of difference between the shot image and the sight image. Blown-out highlights and crushed blacks are caused by the difference of dynamic range between the image sensor installed in a digital camera such as CCD and CMOS and the human visual system. Dynamic range of the shot image is narrower than dynamic range of the sight image. In order to solve the problem, we propose an automatic method to decide an effective exposure range in superposition of edges. We integrate multi-step exposure images using the method. In addition, we try to erase pseudo-edges using the process to blend exposure values. Afterwards, we get a pseudo wide dynamic range image automatically.
Multi-pulse shadowgraphic RGB illumination and detection for flow tracking
NASA Astrophysics Data System (ADS)
Menser, Jan; Schneider, Florian; Dreier, Thomas; Kaiser, Sebastian A.
2018-06-01
This work demonstrates the application of a multi-color LED and a consumer color camera for visualizing phase boundaries in two-phase flows, in particular for particle tracking velocimetry. The LED emits a sequence of short light pulses, red, green, then blue (RGB), and through its color-filter array, the camera captures all three pulses on a single RGB frame. In a backlit configuration, liquid droplets appear as shadows in each color channel. Color reversal and color cross-talk correction yield a series of three frozen-flow images that can be used for further analysis, e.g., determining the droplet velocity by particle tracking. Three example flows are presented, solid particles suspended in water, the penetrating front of a gasoline direct-injection spray, and the liquid break-up region of an "air-assisted" nozzle. Because of the shadowgraphic arrangement, long path lengths through scattering media lower image contrast, while visualization of phase boundaries with high resolution is a strength of this method. Apart from a pulse-and-delay generator, the overall system cost is very low.
Demosaicking for full motion video 9-band SWIR sensor
NASA Astrophysics Data System (ADS)
Kanaev, Andrey V.; Rawhouser, Marjorie; Kutteruf, Mary R.; Yetzbacher, Michael K.; DePrenger, Michael J.; Novak, Kyle M.; Miller, Corey A.; Miller, Christopher W.
2014-05-01
Short wave infrared (SWIR) spectral imaging systems are vital for Intelligence, Surveillance, and Reconnaissance (ISR) applications because of their abilities to autonomously detect targets and classify materials. Typically the spectral imagers are incapable of providing Full Motion Video (FMV) because of their reliance on line scanning. We enable FMV capability for a SWIR multi-spectral camera by creating a repeating pattern of 3x3 spectral filters on a staring focal plane array (FPA). In this paper we present the imagery from an FMV SWIR camera with nine discrete bands and discuss image processing algorithms necessary for its operation. The main task of image processing in this case is demosaicking of the spectral bands i.e. reconstructing full spectral images with original FPA resolution from spatially subsampled and incomplete spectral data acquired with the choice of filter array pattern. To the best of author's knowledge, the demosaicking algorithms for nine or more equally sampled bands have not been reported before. Moreover all existing algorithms developed for demosaicking visible color filter arrays with less than nine colors assume either certain relationship between the visible colors, which are not valid for SWIR imaging, or presence of one color band with higher sampling rate compared to the rest of the bands, which does not conform to our spectral filter pattern. We will discuss and present results for two novel approaches to demosaicking: interpolation using multi-band edge information and application of multi-frame super-resolution to a single frame resolution enhancement of multi-spectral spatially multiplexed images.
NASA Astrophysics Data System (ADS)
Kent, G. M.; Smith, K. D.; Williams, M. C.; Slater, D. E.; Plank, G.; McCarthy, M.; Rojas-Gonzalez, R.; Vernon, F.; Driscoll, N. W.; Hidley, G.
2015-12-01
The Nevada Seismological Laboratory (NSL) at UNR has recently embarked on a bold technical initiative, installing a high-speed (up to 190 Mb/sec) mountaintop-based Internet Protocol (IP) microwave network, enabling a myriad of sensor systems for Multi-Hazard Early Warning detection and response. In the Tahoe Basin, this system is known as AlertTahoe; a similar network has been deployed in north-central Nevada as part of a 5-year-long grant with BLM. The UNR network mirrors the successful HPWREN multi-hazard network run through UCSD; the UNR "Alert" program (Access to Leverage Emergency information in Real Time) has expanded on the original concept by providing a framework for early fire detection and discovery. Both systems do not rely on open-access public Internet services such as those provided by cellular service providers. Instead, they utilize private wireless communication networks to collect data 24/7 in real-time from multiple sensors throughout the system. Utilizing this restricted-access private communication platform enhances system reliability, capability, capacity and versatility for staff and its community of certified users. Both UNR and UCSD fire camera systems are presently being confederated under a common framework to provide end users (e.g., BLM, USFS, CalFire) a unified interface. Earthquake response has been both organizations' primary mission for decades; high-speed IP microwave fundamentally changes the playing field allowing for rapid early detection of wildfires, earthquakes and other natural disasters, greatly improving local and regional disaster response/recovery. For example, networked cameras can be optimally placed for wildfire detection and are significantly less vulnerable due infrastructure hardening and the ability to avoid extreme demands by the public on cellular and other public networks during a crisis. These systems also provide a backup for emergency responders to use when public access communications become overwhelmed or fail during an event. The crowd-sourced fire cameras can be viewed year round through AlertTahoe and AlertSoCal websites with on-demand time-lapse, an integrated real time lightning map, and other useful features.
2016-08-01
7 2.1. DYNAMIC DART GUN EXPERIMENTS...penetration, and cavity formation associated with high-speed projectile penetration of sand. A new half-inch gun was constructed for this project. A...inch gun with them. Data was collected utilizing NSWC’s Cordin 550, 64 frame, high-speed camera. In addition, several student participated in the
Snowstorm Along the China-Mongolia-Russia Borders
NASA Technical Reports Server (NTRS)
2004-01-01
Heavy snowfall on March 12, 2004, across north China's Inner Mongolia Autonomous Region, Mongolia and Russia, caused train and highway traffic to stop for several days along the Russia-China border. This pair of images from the Multi-angle Imaging SpectroRadiometer (MISR) highlights the snow and surface properties across the region on March 13. The left-hand image is a multi-spectral false-color view made from the near-infrared, red, and green bands of MISR's vertical-viewing (nadir) camera. The right-hand image is a multi-angle false-color view made from the red band data of the 46-degree aftward camera, the nadir camera, and the 46-degree forward camera. About midway between the frozen expanse of China's Hulun Nur Lake (along the right-hand edge of the images) and Russia's Torey Lakes (above image center) is a dark linear feature that corresponds with the China-Mongolia border. In the upper portion of the images, many small plumes of black smoke rise from coal and wood fires and blow toward the southeast over the frozen lakes and snow-covered grasslands. Along the upper left-hand portion of the images, in Russia's Yablonovyy mountain range and the Onon River Valley, the terrain becomes more hilly and forested. In the nadir image, vegetation appears in shades of red, owing to its high near-infrared reflectivity. In the multi-angle composite, open-canopy forested areas are indicated by green hues. Since this is a multi-angle composite, the green color arises not from the color of the leaves but from the architecture of the surface cover. The green areas appear brighter at the nadir angle than at the oblique angles because more of the snow-covered surface in the gaps between the trees is visible. Color variations in the multi-angle composite also indicate angular reflectance properties for areas covered by snow and ice. The light blue color of the frozen lakes is due to the increased forward scattering of smooth ice, and light orange colors indicate rougher ice or snow, which scatters more light in the backward direction. The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire Earth between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 22525. The panels cover an area of about 355 kilometers x 380 kilometers, and utilize data from blocks 50 to 52 within World Reference System-2 path 126. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.A Spectralon BRF Data Base for MISR Calibration Application
NASA Technical Reports Server (NTRS)
Bruegge, C.; Chrien, N.; Haner, D.
1999-01-01
The Multi-angle Imaging SpectroRadiometer (MISR) is an Earth observing sensor which will provide global retrievals of aerosols, clouds, and land surface parameters. Instrument specifications require high accuracy absolute calibration, as well as accurate camera-to-camera, band-to-band and pixel-to-pixel relative response determinations.
Atmospheric Science Data Center
2013-04-16
... faint greenish hue in the multi-angle composite. This subtle effect suggests that the nadir camera is observing more of the brighter ... energy and water at the Earth's surface, and for preserving biodiversity. The Multi-angle Imaging SpectroRadiometer observes the daylit ...
Compact full-motion video hyperspectral cameras: development, image processing, and applications
NASA Astrophysics Data System (ADS)
Kanaev, A. V.
2015-10-01
Emergence of spectral pixel-level color filters has enabled development of hyper-spectral Full Motion Video (FMV) sensors operating in visible (EO) and infrared (IR) wavelengths. The new class of hyper-spectral cameras opens broad possibilities of its utilization for military and industry purposes. Indeed, such cameras are able to classify materials as well as detect and track spectral signatures continuously in real time while simultaneously providing an operator the benefit of enhanced-discrimination-color video. Supporting these extensive capabilities requires significant computational processing of the collected spectral data. In general, two processing streams are envisioned for mosaic array cameras. The first is spectral computation that provides essential spectral content analysis e.g. detection or classification. The second is presentation of the video to an operator that can offer the best display of the content depending on the performed task e.g. providing spatial resolution enhancement or color coding of the spectral analysis. These processing streams can be executed in parallel or they can utilize each other's results. The spectral analysis algorithms have been developed extensively, however demosaicking of more than three equally-sampled spectral bands has been explored scarcely. We present unique approach to demosaicking based on multi-band super-resolution and show the trade-off between spatial resolution and spectral content. Using imagery collected with developed 9-band SWIR camera we demonstrate several of its concepts of operation including detection and tracking. We also compare the demosaicking results to the results of multi-frame super-resolution as well as to the combined multi-frame and multiband processing.
NASA Technical Reports Server (NTRS)
Garbeff, Theodore J., II; Baerny, Jennifer K.
2017-01-01
The following details recent efforts undertaken at the NASA Ames Unitary Plan wind tunnels to design and deploy an advanced, production-level infrared (IR) flow visualization data system. Highly sensitive IR cameras, coupled with in-line image processing, have enabled the visualization of wind tunnel model surface flow features as they develop in real-time. Boundary layer transition, shock impingement, junction flow, vortex dynamics, and buffet are routinely observed in both transonic and supersonic flow regimes all without the need of dedicated ramps in test section total temperature. Successful measurements have been performed on wing-body sting mounted test articles, semi-span floor mounted aircraft models, and sting mounted launch vehicle configurations. The unique requirements of imaging in production wind tunnel testing has led to advancements in the deployment of advanced IR cameras in a harsh test environment, robust data acquisition storage and workflow, real-time image processing algorithms, and evaluation of optimal surface treatments. The addition of a multi-camera IR flow visualization data system to the Ames UPWT has demonstrated itself to be a valuable analyses tool in the study of new and old aircraft/launch vehicle aerodynamics and has provided new insight for the evaluation of computational techniques.
NASA Astrophysics Data System (ADS)
Vanmeter, Patrick; Reusch, Lisa; Franz, Paolo; Sarff, John; Goetz, John; Delgado-Aparicio, Louis; den Hartog, Daniel
2017-10-01
The soft X-ray tomography (SXT) system on MST uses four cameras in a double-filter configuration to measure the emitted brightness along forty distinct lines of sight. These measurements can then be inverted to determine the emissivity, which depends on physical properties such as temperature, density, and impurity content. The SXR emissivity should correspond to the structure of the magnetic field; however, there is a discrepancy between the phase of the emissivity inversions and magnetic field reconstructions when using the typical cylindrical approximation to interpret the signal from the toroidal magnetics array. This discrepancy was measured for two distinct plasma conditions using all four SXT cameras, with results supporting the interpretation that it emerges from physical effects of the toroidal geometry. In addition, a new soft x-ray measurement system based on the PILATUS3 photon counting detector will be installed on MST. Emitted photons are counted by an array of pixels with individually adjustable energy cutoffs giving the device more spectral information than the double-filter system. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences program under Award Numbers DE-FC02-05ER54814 and DE-SC0015474.
Phase Curves of Nix and Hydra from the New Horizons Imaging Cameras
NASA Astrophysics Data System (ADS)
Verbiscer, Anne J.; Porter, Simon B.; Buratti, Bonnie J.; Weaver, Harold A.; Spencer, John R.; Showalter, Mark R.; Buie, Marc W.; Hofgartner, Jason D.; Hicks, Michael D.; Ennico-Smith, Kimberly; Olkin, Catherine B.; Stern, S. Alan; Young, Leslie A.; Cheng, Andrew; (The New Horizons Team
2018-01-01
NASA’s New Horizons spacecraft’s voyage through the Pluto system centered on 2015 July 14 provided images of Pluto’s small satellites Nix and Hydra at viewing angles unattainable from Earth. Here, we present solar phase curves of the two largest of Pluto’s small moons, Nix and Hydra, observed by the New Horizons LOng Range Reconnaissance Imager and Multi-spectral Visible Imaging Camera, which reveal the scattering properties of their icy surfaces in visible light. Construction of these solar phase curves enables comparisons between the photometric properties of Pluto’s small moons and those of other icy satellites in the outer solar system. Nix and Hydra have higher visible albedos than those of other resonant Kuiper Belt objects and irregular satellites of the giant planets, but not as high as small satellites of Saturn interior to Titan. Both Nix and Hydra appear to scatter visible light preferentially in the forward direction, unlike most icy satellites in the outer solar system, which are typically backscattering.
2013-03-05
CAPE CANAVERAL, Fla. – A telemetry antenna and tracker camera is attached to the roof of the Launch Control Center, or LCC, in Launch Complex 39 at NASA's Kennedy Space Center in Florida. This antenna and camera system is the first of three to be installed on the LCC roof for the Radio Frequency and Telemetry Station RFTS, which will be used to monitor radio frequency communications from a launch vehicle at Launch Pad 39A or B as well as provide radio frequency relay for a launch vehicle in the Vehicle Assembly Building. The RFTS replaces the shuttle-era communications and tracking labs at Kennedy. The modern RFTS checkout station is designed to primarily support NASA's Space Launch System, or SLS, and Orion spacecraft, but can support multi-user radio frequency tests as the space center transitions to support a variety of rockets and spacecraft. For more information on the modernization efforts at Kennedy, visit the Ground Systems Development and Operations, or GSDO, website at http://go.nasa.gov/groundsystems. Photo credit: NASA/Jim Grossmann
Handheld hyperspectral imager for standoff detection of chemical and biological aerosols
NASA Astrophysics Data System (ADS)
Hinnrichs, Michele; Jensen, James O.; McAnally, Gerard
2004-08-01
Pacific Advanced Technology has developed a small hand held imaging spectrometer, Sherlock, for gas leak and aerosol detection and imaging. The system is based on a patented technique, (IMSS Image Multi-spectral Sensing), that uses diffractive optics and image processing algorithms to detect spectral information about objects in the scene of the camera. This cameras technology has been tested at Dugway Proving Ground and Dstl Porton Down facilities looking at Chemical and Biological agent simulants. In addition to Chemical and Biological detection, the camera has been used for environmental monitoring of green house gases and is currently undergoing extensive laboratory and field testing by the Gas Technology Institute, British Petroleum and Shell Oil for applications for gas leak detection and repair. In this paper we will present some of the results from the data collection at the TRE test at Dugway Proving Ground during the summer of 2002 and laboratory testing at the Dstl facility at Porton Down in the UK in the fall of 2002.
2002-03-01
Carrying the STS-109 crew of seven, the Space Shuttle Orbiter Columbia blasted from its launch pad as it began its 27th flight and 108th flight overall in NASA's Space Shuttle Program. Launched March 1, 2002, the goal of the mission was the maintenance and upgrade of the Hubble Space Telescope (HST) which was developed, designed, and constructed by the Marshall Space Flight Center. Captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, the HST received the following upgrades: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when it original coolant ran out. Four of the crewmembers performed 5 space walks in the 10 days, 22 hours, and 11 minutes of the the STS-109 mission.
Orthogonal strip HPGe planar SmartPET detectors in Compton configuration
NASA Astrophysics Data System (ADS)
Boston, H. C.; Gillam, J.; Boston, A. J.; Cooper, R. J.; Cresswell, J.; Grint, A. N.; Mather, A. R.; Nolan, P. J.; Scraggs, D. P.; Turk, G.; Hall, C. J.; Lazarus, I.; Berry, A.; Beveridge, T.; Lewis, R.
2007-10-01
The evolution of Germanium detector technology over the last decade has lead to the possibility that they can be employed in medical and security imaging. The potential of excellent energy resolution coupled with good position information that Germanium affords removes the necessity for mechanical collimators that would be required in a conventional gamma camera system. By removing this constraint, the overall dose to the patient can be reduced or the throughput of the system can be increased. An additional benefit of excellent energy resolution is that tight gates can be placed on energies from either a multi-lined gamma source or from multi-nuclide sources increasing the number of sources that can be used in medical imaging. In terms of security imaging, segmented Germanium gives directionality and excellent spectroscopic information.
Evaluation of Particle Image Velocimetry Measurement Using Multi-wavelength Illumination
NASA Astrophysics Data System (ADS)
Lai, HC; Chew, TF; Razak, NA
2018-05-01
In past decades, particle image velocimetry (PIV) has been widely used in measuring fluid flow and a lot of researches have been done to improve the PIV technique. Many researches are conducted on high power light emitting diode (HPLED) to replace the traditional laser illumination system in PIV. As an extended work to the research in PIV illumination system, two high power light emitting diodes (HPLED) with different wavelength are introduced as PIV illumination system. The objective of this research is using dual colours LED to directly replace laser as illumination system in order for a single frame to be captured by a normal camera instead of a high speed camera. Dual colours HPLEDs PIV are capable with single frame double pulses mode which able to plot the velocity vector of the particles after correlation. An illumination system is designed and fabricated and evaluated by measuring water flow in a small tank. The results indicates that HPLEDs promises a few advantages in terms of cost, safety and performance. It has a high potential to be develop into an alternative for PIV in the near future.
High-Definition Television (HDTV) Images for Earth Observations and Earth Science Applications
NASA Technical Reports Server (NTRS)
Robinson, Julie A.; Holland, S. Douglas; Runco, Susan K.; Pitts, David E.; Whitehead, Victor S.; Andrefouet, Serge M.
2000-01-01
As part of Detailed Test Objective 700-17A, astronauts acquired Earth observation images from orbit using a high-definition television (HDTV) camcorder, Here we provide a summary of qualitative findings following completion of tests during missions STS (Space Transport System)-93 and STS-99. We compared HDTV imagery stills to images taken using payload bay video cameras, Hasselblad film camera, and electronic still camera. We also evaluated the potential for motion video observations of changes in sunlight and the use of multi-aspect viewing to image aerosols. Spatial resolution and color quality are far superior in HDTV images compared to National Television Systems Committee (NTSC) video images. Thus, HDTV provides the first viable option for video-based remote sensing observations of Earth from orbit. Although under ideal conditions, HDTV images have less spatial resolution than medium-format film cameras, such as the Hasselblad, under some conditions on orbit, the HDTV image acquired compared favorably with the Hasselblad. Of particular note was the quality of color reproduction in the HDTV images HDTV and electronic still camera (ESC) were not compared with matched fields of view, and so spatial resolution could not be compared for the two image types. However, the color reproduction of the HDTV stills was truer than colors in the ESC images. As HDTV becomes the operational video standard for Space Shuttle and Space Station, HDTV has great potential as a source of Earth-observation data. Planning for the conversion from NTSC to HDTV video standards should include planning for Earth data archiving and distribution.
A Gradient Optimization Approach to Adaptive Multi-Robot Control
2009-09-01
implemented for deploying a group of three flying robots with downward facing cameras to monitor an environment on the ground. Thirdly, the multi-robot...theoretically proven, and implemented on multi-robot platforms. Thesis Supervisor: Daniela Rus Title: Professor of Electrical Engineering and Computer...often nonlinear, and they are coupled through a network which changes over time. Thirdly, implementing multi-robot controllers requires maintaining mul
Design of the high resolution optical instrument for the Pleiades HR Earth observation satellites
NASA Astrophysics Data System (ADS)
Lamard, Jean-Luc; Gaudin-Delrieu, Catherine; Valentini, David; Renard, Christophe; Tournier, Thierry; Laherrere, Jean-Marc
2017-11-01
As part of its contribution to Earth observation from space, ALCATEL SPACE designed, built and tested the High Resolution cameras for the European intelligence satellites HELIOS I and II. Through these programmes, ALCATEL SPACE enjoys an international reputation. Its capability and experience in High Resolution instrumentation is recognised by the most customers. Coming after the SPOT program, it was decided to go ahead with the PLEIADES HR program. PLEIADES HR is the optical high resolution component of a larger optical and radar multi-sensors system : ORFEO, which is developed in cooperation between France and Italy for dual Civilian and Defense use. ALCATEL SPACE has been entrusted by CNES with the development of the high resolution camera of the Earth observation satellites PLEIADES HR. The first optical satellite of the PLEIADES HR constellation will be launched in mid-2008, the second will follow in 2009. To minimize the development costs, a mini satellite approach has been selected, leading to a compact concept for the camera design. The paper describes the design and performance budgets of this novel high resolution and large field of view optical instrument with emphasis on the technological features. This new generation of camera represents a breakthrough in comparison with the previous SPOT cameras owing to a significant step in on-ground resolution, which approaches the capabilities of aerial photography. Recent advances in detector technology, optical fabrication and electronics make it possible for the PLEIADES HR camera to achieve their image quality performance goals while staying within weight and size restrictions normally considered suitable only for much lower performance systems. This camera design delivers superior performance using an innovative low power, low mass, scalable architecture, which provides a versatile approach for a variety of imaging requirements and allows for a wide number of possibilities of accommodation with a mini-satellite class platform.
Multiple pedestrian detection using IR LED stereo camera
NASA Astrophysics Data System (ADS)
Ling, Bo; Zeifman, Michael I.; Gibson, David R. P.
2007-09-01
As part of the U.S. Department of Transportations Intelligent Vehicle Initiative (IVI) program, the Federal Highway Administration (FHWA) is conducting R&D in vehicle safety and driver information systems. There is an increasing number of applications where pedestrian monitoring is of high importance. Visionbased pedestrian detection in outdoor scenes is still an open challenge. People dress in very different colors that sometimes blend with the background, wear hats or carry bags, and stand, walk and change directions unpredictably. The background is various, containing buildings, moving or parked cars, bicycles, street signs, signals, etc. Furthermore, existing pedestrian detection systems perform only during daytime, making it impossible to detect pedestrians at night. Under FHWA funding, we are developing a multi-pedestrian detection system using IR LED stereo camera. This system, without using any templates, detects the pedestrians through statistical pattern recognition utilizing 3D features extracted from the disparity map. A new IR LED stereo camera is being developed, which can help detect pedestrians during daytime and night time. Using the image differencing and denoising, we have also developed new methods to estimate the disparity map of pedestrians in near real time. Our system will have a hardware interface with the traffic controller through wireless communication. Once pedestrians are detected, traffic signals at the street intersections will change phases to alert the drivers of approaching vehicles. The initial test results using images collected at a street intersection show that our system can detect pedestrians in near real time.
New Airborne Sensors and Platforms for Solving Specific Tasks in Remote Sensing
NASA Astrophysics Data System (ADS)
Kemper, G.
2012-07-01
A huge number of small and medium sized sensors entered the market. Today's mid format sensors reach 80 MPix and allow to run projects of medium size, comparable with the first big format digital cameras about 6 years ago. New high quality lenses and new developments in the integration prepared the market for photogrammetric work. Companies as Phase One or Hasselblad and producers or integrators as Trimble, Optec, and others utilized these cameras for professional image production. In combination with small camera stabilizers they can be used also in small aircraft and make the equipment small and easy transportable e.g. for rapid assessment purposes. The combination of different camera sensors enables multi or hyper-spectral installations e.g. useful for agricultural or environmental projects. Arrays of oblique viewing cameras are in the market as well, in many cases these are small and medium format sensors combined as rotating or shifting devices or just as a fixed setup. Beside the proper camera installation and integration, also the software that controls the hardware and guides the pilot has to solve much more tasks than a normal FMS did in the past. Small and relatively cheap Laser Scanners (e.g. Riegl) are in the market and a proper combination with MS Cameras and an integrated planning and navigation is a challenge that has been solved by different softwares. Turnkey solutions are available e.g. for monitoring power line corridors where taking images is just a part of the job. Integration of thermal camera systems with laser scanner and video capturing must be combined with specific information of the objects stored in a database and linked when approaching the navigation point.
"Sturdy as a house with four windows," the star tracker of the future
NASA Astrophysics Data System (ADS)
Duivenvoorde, Tom; Leijtens, Johan; van der Heide, Erik J.
2017-11-01
Ongoing miniaturization of spacecraft demands the reduction in size of Attitude and Orbit Control Systems (AOCS). Therefore TNO has created a new design of a multi aperture, high performance, and miniaturized star tracker. The innovative design incorporates the latest developments in camera technology, attitude calculation and mechanical design into a system with 5 arc seconds accuracy, making the system usable for many applications. In this paper the results are presented of the system design and analysis, as well as the performance predictions for the Multi Aperture Baffled Star Tracker (MABS). The highly integrated system consists of multiple apertures without the need for external baffles, resulting in major advantages in mass, volume, alignment with the spacecraft and relative aperture stability. In the analysis part of this paper, the thermal and mechanical stability are discussed. In the final part the simulation results will be described that have lead to the predicted accuracy of the star tracker system and a peek into the future of attitude sensors is given.
Multi-Head Very High Power Strobe System For Motion Picture Special Effects
NASA Astrophysics Data System (ADS)
Lovoi, P. A.; Fink, Michael L.
1983-10-01
A very large camera synchronizable strobe system has been developed for motion picture special effects. This system, the largest ever built, was delivered to MGM/UA to be used in the movie "War Games". The system consists of 12 individual strobe heads and a power supply distribution system. Each strobe head operates independently and may be flashed up to 24 times per second under computer control. An energy of 480 Joules per flash is used in six strobe heads and 240 Joules per flash in the remaining six strobe heads. The beam pattern is rectangular with a FWHM of 60° x 48°.
Multi-energy SXR cameras for magnetically confined fusion plasmas (invited)
NASA Astrophysics Data System (ADS)
Delgado-Aparicio, L. F.; Maddox, J.; Pablant, N.; Hill, K.; Bitter, M.; Rice, J. E.; Granetz, R.; Hubbard, A.; Irby, J.; Greenwald, M.; Marmar, E.; Tritz, K.; Stutman, D.; Stratton, B.; Efthimion, P.
2016-11-01
A compact multi-energy soft x-ray camera has been developed for time, energy and space-resolved measurements of the soft-x-ray emissivity in magnetically confined fusion plasmas. Multi-energy soft x-ray imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (Te, nZ, ΔZeff, and ne,fast). The electron temperature can be obtained by modeling the slope of the continuum radiation from ratios of the available brightness and inverted radial emissivity profiles over multiple energy ranges. Impurity density measurements are also possible using the line-emission from medium- to high-Z impurities to separate the background as well as transient levels of metal contributions. This technique should be explored also as a burning plasma diagnostic in-view of its simplicity and robustness.
NASA Astrophysics Data System (ADS)
Brown, T.; Borevitz, J. O.; Zimmermann, C.
2010-12-01
We have a developed a camera system that can record hourly, gigapixel (multi-billion pixel) scale images of an ecosystem in a 360x90 degree panorama. The “Gigavision” camera system is solar-powered and can wirelessly stream data to a server. Quantitative data collection from multiyear timelapse gigapixel images is facilitated through an innovative web-based toolkit for recording time-series data on developmental stages (phenology) from any plant in the camera’s field of view. Gigapixel images enable time-series recording of entire landscapes with a resolution sufficient to record phenology from a majority of individuals in entire populations of plants. When coupled with next generation sequencing, quantitative population genomics can be performed in a landscape context linking ecology and evolution in situ and in real time. The Gigavision camera system achieves gigapixel image resolution by recording rows and columns of overlapping megapixel images. These images are stitched together into a single gigapixel resolution image using commercially available panorama software. Hardware consists of a 5-18 megapixel resolution DSLR or Network IP camera mounted on a pair of heavy-duty servo motors that provide pan-tilt capabilities. The servos and camera are controlled with a low-power Windows PC. Servo movement, power switching, and system status monitoring are enabled with Phidgets-brand sensor boards. System temperature, humidity, power usage, and battery voltage are all monitored at 5 minute intervals. All sensor data is uploaded via cellular or 802.11 wireless to an interactive online interface for easy remote monitoring of system status. Systems with direct internet connections upload the full sized images directly to our automated stitching server where they are stitched and available online for viewing within an hour of capture. Systems with cellular wireless upload an 80 megapixel “thumbnail” of each larger panorama and full-sized images are manually retrieved at bi-weekly intervals. Our longer-term goal is to make gigapixel time-lapse datasets available online in an interactive interface that layers plant-level phenology data with gigapixel resolution images, genomic sequence data from individual plants with weather and other abitotic sensor data. Co-visualization of all of these data types provides researchers with a powerful new tool for examining complex ecological interactions across scales from the individual to the ecosystem. We will present detailed phenostage data from more than 100 plants of multiple species from our Gigavision timelapse camera at our “Big Blowout East” field site in the Indiana Dunes State Park, IN. This camera has been recording three to four 700 million pixel images a day since February 28, 2010. The camera field of view covers an area of about 7 hectares resulting in an average image resolution of about 1 pixel per centimeter over the entire site. We will also discuss some of the many technological challenges with developing and maintaining these types of hardware systems, collecting quantitative data from gigapixel resolution time-lapse data and effectively managing terabyte-sized datasets of millions of images.
NASA Astrophysics Data System (ADS)
Robert, K.; Matabos, M.; Sarrazin, J.; Sarradin, P.; Lee, R. W.; Juniper, K.
2010-12-01
Hydrothermal vent environments are among the most dynamic benthic habitats in the ocean. The relative roles of physical and biological factors in shaping vent community structure remain unclear. Undersea cabled observatories offer the power and bandwidth required for high-resolution, time-series study of the dynamics of vent communities and the physico-chemical forces that influence them. The NEPTUNE Canada cabled instrument array at the Endeavour hydrothermal vents provides a unique laboratory for researchers to conduct long-term, integrated studies of hydrothermal vent ecosystem dynamics in relation to environmental variability. Beginning in September-October 2010, NEPTUNE Canada (NC) will be deploying a multi-disciplinary suite of instruments on the Endeavour Segment of the Juan de Fuca Ridge. Two camera and sensor systems will be used to study ecosystem dynamics in relation to hydrothermal discharge. These studies will make use of new experimental protocols for time-series observations that we have been developing since 2008 at other observatory sites connected to the VENUS and NC networks. These protocols include sampling design, camera calibration (i.e. structure, position, light, settings) and image analysis methodologies (see communication by Aron et al.). The camera systems to be deployed in the Main Endeavour vent field include a Sidus high definition video camera (2010) and the TEMPO-mini system (2011), designed by IFREMER (France). Real-time data from three sensors (O2, dissolved Fe, temperature) integrated with the TEMPO-mini system will enhance interpretation of imagery. For the first year of observations, a suite of internally recording temperature probes will be strategically placed in the field of view of the Sidus camera. These installations aim at monitoring variations in vent community structure and dynamics (species composition and abundances, interactions within and among species) in response to changes in environmental conditions at different temporal scales. High-resolution time-series studies also provide a mean of studying population dynamics, biological rhythms, organism growth and faunal succession. In addition to programmed time-series monitoring, the NC infrastructure will also permit manual and automated modification of observational protocols in response to natural events. This will enhance our ability to document potentially critical but short-lived environmental forces affecting vent communities.
A Fast Visible Camera Divertor-Imaging Diagnostic on DIII-D
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roquemore, A; Maingi, R; Lasnier, C
2007-06-19
In recent campaigns, the Photron Ultima SE fast framing camera has proven to be a powerful diagnostic when applied to imaging divertor phenomena on the National Spherical Torus Experiment (NSTX). Active areas of NSTX divertor research addressed with the fast camera include identification of types of EDGE Localized Modes (ELMs)[1], dust migration, impurity behavior and a number of phenomena related to turbulence. To compare such edge and divertor phenomena in low and high aspect ratio plasmas, a multi-institutional collaboration was developed for fast visible imaging on NSTX and DIII-D. More specifically, the collaboration was proposed to compare the NSTX smallmore » type V ELM regime [2] and the residual ELMs observed during Type I ELM suppression with external magnetic perturbations on DIII-D[3]. As part of the collaboration effort, the Photron camera was installed recently on DIII-D with a tangential view similar to the view implemented on NSTX, enabling a direct comparison between the two machines. The rapid implementation was facilitated by utilization of the existing optics that coupled the visible spectral output from the divertor vacuum ultraviolet UVTV system, which has a view similar to the view developed for the divertor tangential TV camera [4]. A remote controlled filter wheel was implemented, as was the radiation shield required for the DIII-D installation. The installation and initial operation of the camera are described in this paper, and the first images from the DIII-D divertor are presented.« less
NASA Technical Reports Server (NTRS)
Jackson, T. J.; Shiue, J.; Oneill, P.; Wang, J.; Fuchs, J.; Owe, M.
1984-01-01
The verification of a multi-sensor aircraft system developed to study soil moisture applications is discussed. This system consisted of a three beam push broom L band microwave radiometer, a thermal infrared scanner, a multispectral scanner, video and photographic cameras and an onboard navigational instrument. Ten flights were made of agricultural sites in Maryland and Delaware with little or no vegetation cover. Comparisons of aircraft and ground measurements showed that the system was reliable and consistent. Time series analysis of microwave and evaporation data showed a strong similarity that indicates a potential direction for future research.
The GCT camera for the Cherenkov Telescope Array
NASA Astrophysics Data System (ADS)
Lapington, J. S.; Abchiche, A.; Allan, D.; Amans, J.-P.; Armstrong, T. P.; Balzer, A.; Berge, D.; Boisson, C.; Bousquet, J.-J.; Bose, R.; Brown, A. M.; Bryan, M.; Buchholtz, G.; Buckley, J.; Chadwick, P. M.; Costantini, H.; Cotter, G.; Daniel, M. K.; De Franco, A.; De Frondat, F.; Dournaux, J.-L.; Dumas, D.; Ernenwein, J.-P.; Fasola, G.; Funk, S.; Gironnet, J.; Graham, J. A.; Greenshaw, T.; Hervet, O.; Hidaka, N.; Hinton, J. A.; Huet, J.-M.; Jankowsky, D.; Jegouzo, I.; Jogler, T.; Kawashima, T.; Kraus, M.; Laporte, P.; Leach, S.; Lefaucheur, J.; Markoff, S.; Melse, T.; Minaya, I. A.; Mohrmann, L.; Molyneux, P.; Moore, P.; Nolan, S. J.; Okumura, A.; Osborne, J. P.; Parsons, R. D.; Rosen, S.; Ross, D.; Rowell, G.; Rulten, C. B.; Sato, Y.; Sayede, F.; Schmoll, J.; Schoorlemmer, H.; Servillat, M.; Sol, H.; Stamatescu, V.; Stephan, M.; Stuik, R.; Sykes, J.; Tajima, H.; Thornhill, J.; Tibaldo, L.; Trichard, C.; Varner, G.; Vink, J.; Watson, J. J.; White, R.; Yamane, N.; Zech, A.; Zink, A.; Zorn, J.; CTA Consortium
2017-12-01
The Gamma Cherenkov Telescope (GCT) is one of the designs proposed for the Small Sized Telescope (SST) section of the Cherenkov Telescope Array (CTA). The GCT uses dual-mirror optics, resulting in a compact telescope with good image quality and a large field of view with a smaller, more economical, camera than is achievable with conventional single mirror solutions. The photon counting GCT camera is designed to record the flashes of atmospheric Cherenkov light from gamma and cosmic ray initiated cascades, which last only a few tens of nanoseconds. The GCT optics require that the camera detectors follow a convex surface with a radius of curvature of 1 m and a diameter of 35 cm, which is approximated by tiling the focal plane with 32 modules. The first camera prototype is equipped with multi-anode photomultipliers, each comprising an 8×8 array of 6×6 mm2 pixels to provide the required angular scale, adding up to 2048 pixels in total. Detector signals are shaped, amplified and digitised by electronics based on custom ASICs that provide digitisation at 1 GSample/s. The camera is self-triggering, retaining images where the focal plane light distribution matches predefined spatial and temporal criteria. The electronics are housed in the liquid-cooled, sealed camera enclosure. LED flashers at the corners of the focal plane provide a calibration source via reflection from the secondary mirror. The first GCT camera prototype underwent preliminary laboratory tests last year. In November 2015, the camera was installed on a prototype GCT telescope (SST-GATE) in Paris and was used to successfully record the first Cherenkov light of any CTA prototype, and the first Cherenkov light seen with such a dual-mirror optical system. A second full-camera prototype based on Silicon Photomultipliers is under construction. Up to 35 GCTs are envisaged for CTA.
Characterization of SWIR cameras by MRC measurements
NASA Astrophysics Data System (ADS)
Gerken, M.; Schlemmer, H.; Haan, Hubertus A.; Siemens, Christofer; Münzberg, M.
2014-05-01
Cameras for the SWIR wavelength range are becoming more and more important because of the better observation range for day-light operation under adverse weather conditions (haze, fog, rain). In order to choose the best suitable SWIR camera or to qualify a camera for a given application, characterization of the camera by means of the Minimum Resolvable Contrast MRC concept is favorable as the MRC comprises all relevant properties of the instrument. With the MRC known for a given camera device the achievable observation range can be calculated for every combination of target size, illumination level or weather conditions. MRC measurements in the SWIR wavelength band can be performed widely along the guidelines of the MRC measurements of a visual camera. Typically measurements are performed with a set of resolution targets (e.g. USAF 1951 target) manufactured with different contrast values from 50% down to less than 1%. For a given illumination level the achievable spatial resolution is then measured for each target. The resulting curve is showing the minimum contrast that is necessary to resolve the structure of a target as a function of spatial frequency. To perform MRC measurements for SWIR cameras at first the irradiation parameters have to be given in radiometric instead of photometric units which are limited in their use to the visible range. In order to do so, SWIR illumination levels for typical daylight and twilight conditions have to be defined. At second, a radiation source is necessary with appropriate emission in the SWIR range (e.g. incandescent lamp) and the irradiance has to be measured in W/m2 instead of Lux = Lumen/m2. At third, the contrast values of the targets have to be calibrated newly for the SWIR range because they typically differ from the values determined for the visual range. Measured MRC values of three cameras are compared to the specified performance data of the devices and the results of a multi-band in-house designed Vis-SWIR camera system are discussed.
Evangelista, Dennis J.; Ray, Dylan D.; Hedrick, Tyson L.
2016-01-01
ABSTRACT Ecological, behavioral and biomechanical studies often need to quantify animal movement and behavior in three dimensions. In laboratory studies, a common tool to accomplish these measurements is the use of multiple, calibrated high-speed cameras. Until very recently, the complexity, weight and cost of such cameras have made their deployment in field situations risky; furthermore, such cameras are not affordable to many researchers. Here, we show how inexpensive, consumer-grade cameras can adequately accomplish these measurements both within the laboratory and in the field. Combined with our methods and open source software, the availability of inexpensive, portable and rugged cameras will open up new areas of biological study by providing precise 3D tracking and quantification of animal and human movement to researchers in a wide variety of field and laboratory contexts. PMID:27444791
Design and Development of a Real-Time Model Attitude Measurement System for Hypersonic Facilities
NASA Technical Reports Server (NTRS)
Jones, Thomas W.; Lunsford, Charles B.
2005-01-01
A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and applies photogrammetric principles for point tracking to compute model position including pitch, roll and yaw variables. A discussion of the constraints encountered during the design, development, and testing process, including lighting, vibration, operational range and optical access is included. Initial measurement results from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.
Design and Development of a Real-Time Model Attitude Measurement System for Hypersonic Facilities
NASA Technical Reports Server (NTRS)
Jones, Thomas W.; Lunsford, Charles B.
2004-01-01
A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and applies photogrammetric principles for point tracking to compute model position including pitch, roll and yaw variables. A discussion of the constraints encountered during the design, development, and testing process, including lighting, vibration, operational range and optical access is included. Initial measurement results from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.
EVA 4 - Massimino with EMS on RMS arm
2002-03-07
STS109-323-035 (7 March 2002) --- Astronaut Michael J. Massimino, on the shuttles robotic arm, prepares to install the Electronic Support Module (ESM) in the aft shroud of the Hubble Space Telescope (HST), with the assistance of astronaut James H. Newman (out of frame). The module will support a new experimental cooling system to be installed during the next day's fifth and final scheduled spacewalk of the mission. That cooling system is designed to bring the telescope's Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) back to life.
EVA 5 - Grunsfeld installs radiator
2002-03-08
STS109-315-007 (8 March 2002) --- Astronaut John M. Grunsfeld, STS-109 payload commander, anchored on the end of the Space Shuttle Columbias Remote Manipulator System (RMS) robotic arm, moves toward the giant Hubble Space Telescope (HST) temporarily hosted in the orbiters cargo bay. Astronaut Richard M. Linnehan (out of frame) works in tandem with Grunsfeld during this fifth and final session of extravehicular activity (EVA). Activities for the space walk centered around the Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) to install a Cryogenic Cooler and its Cooling System Radiator.
Multi-microphone adaptive array augmented with visual cueing.
Gibson, Paul L; Hedin, Dan S; Davies-Venn, Evelyn E; Nelson, Peggy; Kramer, Kevin
2012-01-01
We present the development of an audiovisual array that enables hearing aid users to converse with multiple speakers in reverberant environments with significant speech babble noise where their hearing aids do not function well. The system concept consists of a smartphone, a smartphone accessory, and a smartphone software application. The smartphone accessory concept is a multi-microphone audiovisual array in a form factor that allows attachment to the back of the smartphone. The accessory will also contain a lower power radio by which it can transmit audio signals to compatible hearing aids. The smartphone software application concept will use the smartphone's built in camera to acquire images and perform real-time face detection using the built-in face detection support of the smartphone. The audiovisual beamforming algorithm uses the location of talking targets to improve the signal to noise ratio and consequently improve the user's speech intelligibility. Since the proposed array system leverages a handheld consumer electronic device, it will be portable and low cost. A PC based experimental system was developed to demonstrate the feasibility of an audiovisual multi-microphone array and these results are presented.
Image degradation characteristics and restoration based on regularization for diffractive imaging
NASA Astrophysics Data System (ADS)
Zhi, Xiyang; Jiang, Shikai; Zhang, Wei; Wang, Dawei; Li, Yun
2017-11-01
The diffractive membrane optical imaging system is an important development trend of ultra large aperture and lightweight space camera. However, related investigations on physics-based diffractive imaging degradation characteristics and corresponding image restoration methods are less studied. In this paper, the model of image quality degradation for the diffraction imaging system is first deduced mathematically based on diffraction theory and then the degradation characteristics are analyzed. On this basis, a novel regularization model of image restoration that contains multiple prior constraints is established. After that, the solving approach of the equation with the multi-norm coexistence and multi-regularization parameters (prior's parameters) is presented. Subsequently, the space-variant PSF image restoration method for large aperture diffractive imaging system is proposed combined with block idea of isoplanatic region. Experimentally, the proposed algorithm demonstrates its capacity to achieve multi-objective improvement including MTF enhancing, dispersion correcting, noise and artifact suppressing as well as image's detail preserving, and produce satisfactory visual quality. This can provide scientific basis for applications and possesses potential application prospects on future space applications of diffractive membrane imaging technology.
Design of a compact low-power human-computer interaction equipment for hand motion
NASA Astrophysics Data System (ADS)
Wu, Xianwei; Jin, Wenguang
2017-01-01
Human-Computer Interaction (HCI) raises demand of convenience, endurance, responsiveness and naturalness. This paper describes a design of a compact wearable low-power HCI equipment applied to gesture recognition. System combines multi-mode sense signals: the vision sense signal and the motion sense signal, and the equipment is equipped with the depth camera and the motion sensor. The dimension (40 mm × 30 mm) and structure is compact and portable after tight integration. System is built on a module layered framework, which contributes to real-time collection (60 fps), process and transmission via synchronous confusion with asynchronous concurrent collection and wireless Blue 4.0 transmission. To minimize equipment's energy consumption, system makes use of low-power components, managing peripheral state dynamically, switching into idle mode intelligently, pulse-width modulation (PWM) of the NIR LEDs of the depth camera and algorithm optimization by the motion sensor. To test this equipment's function and performance, a gesture recognition algorithm is applied to system. As the result presents, general energy consumption could be as low as 0.5 W.
Applied learning-based color tone mapping for face recognition in video surveillance system
NASA Astrophysics Data System (ADS)
Yew, Chuu Tian; Suandi, Shahrel Azmin
2012-04-01
In this paper, we present an applied learning-based color tone mapping technique for video surveillance system. This technique can be applied onto both color and grayscale surveillance images. The basic idea is to learn the color or intensity statistics from a training dataset of photorealistic images of the candidates appeared in the surveillance images, and remap the color or intensity of the input image so that the color or intensity statistics match those in the training dataset. It is well known that the difference in commercial surveillance cameras models, and signal processing chipsets used by different manufacturers will cause the color and intensity of the images to differ from one another, thus creating additional challenges for face recognition in video surveillance system. Using Multi-Class Support Vector Machines as the classifier on a publicly available video surveillance camera database, namely SCface database, this approach is validated and compared to the results of using holistic approach on grayscale images. The results show that this technique is suitable to improve the color or intensity quality of video surveillance system for face recognition.
Optical sensing in laser machining
NASA Astrophysics Data System (ADS)
Smurov, Igor; Doubenskaia, Maria
2009-05-01
Optical monitoring of temperature evolution and temperature distribution in laser machining provides important information to optimise and to control technological process under study. The multi-wavelength pyrometer is used to measure brightness temperature under the pulsed action of Nd:YAG laser on stainless steel substrates. Specially developed "notch" filters (10-6 transparency at 1.06 μm wavelength) are applied to avoid the influence of laser radiation on temperature measurements. The true temperature is restored based on the method of multi-colour pyrometry. Temperature monitoring of the thin-walled gilded kovar boxes is applied to detect deviation of the welding seam from its optimum position. The pyrometers are used to control CO2-laser welding of steel and Ti plates: misalignment of the welded plates, variation of the welding geometry, internal defects, deviation of the laser beam trajectory from the junction, etc. The temperature profiles along and across the welding axis are measured by the 2D pyrometer. When using multi-component powder blends in laser cladding, for example metal matrix composite with ceramic reinforcement, one needs to control temperature of the melt to avoid thermal decomposition of certain compounds (as WC) and to assure melting of the base metal (as Co). Infra-red camera FLIR Phoenix RDAS provides detailed information on distribution of brightness temperature in laser cladding zone. CCD-camera based diagnostic system is used to measure particles-in-flight velocity and size distribution.
NASA Astrophysics Data System (ADS)
Cvetkovic, Sascha D.; Schirris, Johan; de With, Peter H. N.
2009-01-01
For real-time imaging in surveillance applications, visibility of details is of primary importance to ensure customer confidence. If we display High Dynamic-Range (HDR) scenes whose contrast spans four or more orders of magnitude on a conventional monitor without additional processing, results are unacceptable. Compression of the dynamic range is therefore a compulsory part of any high-end video processing chain because standard monitors are inherently Low- Dynamic Range (LDR) devices with maximally two orders of display dynamic range. In real-time camera processing, many complex scenes are improved with local contrast enhancements, bringing details to the best possible visibility. In this paper, we show how a multi-scale high-frequency enhancement scheme, in which gain is a non-linear function of the detail energy, can be used for the dynamic range compression of HDR real-time video camera signals. We also show the connection of our enhancement scheme to the processing way of the Human Visual System (HVS). Our algorithm simultaneously controls perceived sharpness, ringing ("halo") artifacts (contrast) and noise, resulting in a good balance between visibility of details and non-disturbance of artifacts. The overall quality enhancement, suitable for both HDR and LDR scenes, is based on a careful selection of the filter types for the multi-band decomposition and a detailed analysis of the signal per frequency band.
Planetary Image Geometry Library
NASA Technical Reports Server (NTRS)
Deen, Robert C.; Pariser, Oleg
2010-01-01
The Planetary Image Geometry (PIG) library is a multi-mission library used for projecting images (EDRs, or Experiment Data Records) and managing their geometry for in-situ missions. A collection of models describes cameras and their articulation, allowing application programs such as mosaickers, terrain generators, and pointing correction tools to be written in a multi-mission manner, without any knowledge of parameters specific to the supported missions. Camera model objects allow transformation of image coordinates to and from view vectors in XYZ space. Pointing models, specific to each mission, describe how to orient the camera models based on telemetry or other information. Surface models describe the surface in general terms. Coordinate system objects manage the various coordinate systems involved in most missions. File objects manage access to metadata (labels, including telemetry information) in the input EDRs and RDRs (Reduced Data Records). Label models manage metadata information in output files. Site objects keep track of different locations where the spacecraft might be at a given time. Radiometry models allow correction of radiometry for an image. Mission objects contain basic mission parameters. Pointing adjustment ("nav") files allow pointing to be corrected. The object-oriented structure (C++) makes it easy to subclass just the pieces of the library that are truly mission-specific. Typically, this involves just the pointing model and coordinate systems, and parts of the file model. Once the library was developed (initially for Mars Polar Lander, MPL), adding new missions ranged from two days to a few months, resulting in significant cost savings as compared to rewriting all the application programs for each mission. Currently supported missions include Mars Pathfinder (MPF), MPL, Mars Exploration Rover (MER), Phoenix, and Mars Science Lab (MSL). Applications based on this library create the majority of operational image RDRs for those missions. A Java wrapper around the library allows parts of it to be used from Java code (via a native JNI interface). Future conversions of all or part of the library to Java are contemplated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cuddy-Walsh, SG; University of Ottawa Heart Institute; Wells, RG
2014-08-15
Myocardial perfusion imaging (MPI) with Single Photon Emission Computed Tomography (SPECT) is invaluable in the diagnosis and management of heart disease. It provides essential information on myocardial blood flow and ischemia. Multi-pinhole dedicated cardiac-SPECT cameras offer improved count sensitivity, and spatial and energy resolutions over parallel-hole camera designs however variable sensitivity across the field-of-view (FOV) can lead to position-dependent noise variations. Since MPI evaluates differences in the signal-to-noise ratio, noise variations in the camera could significantly impact the sensitivity of the test for ischemia. We evaluated the noise characteristics of GE Healthcare's Discovery NM530c camera with a goal of optimizingmore » the accuracy of our patient assessment and thereby improving outcomes. Theoretical sensitivity maps of the camera FOV, including attenuation effects, were estimated analytically based on the distance and angle between the spatial position of a given voxel and each pinhole. The standard deviation in counts, σ was inferred for each voxel position from the square root of the sensitivity mapped at that position. Noise was measured experimentally from repeated (N=16) acquisitions of a uniform spherical Tc-99m-water phantom. The mean (μ) and standard deviation (σ) were calculated for each voxel position in the reconstructed FOV. Noise increased ∼2.1× across a 12 cm sphere. A correlation of 0.53 is seen when experimental noise is compared with theory suggesting that ∼53% of the noise is attributed to the combined effects of attenuation and the multi-pinhole geometry. Further investigations are warranted to determine the clinical impact of the position-dependent noise variation.« less
NASA Technical Reports Server (NTRS)
Humphreys, Brad; Bellisario, Brian; Gallo, Christopher; Thompson, William K.; Lewandowski, Beth
2016-01-01
Long duration space travel to Mars or to an asteroid will expose astronauts to extended periods of reduced gravity. Since gravity is not present to aid loading, astronauts will use resistive and aerobic exercise regimes for the duration of the space flight to minimize the loss of bone density, muscle mass and aerobic capacity that occurs during exposure to a reduced gravity environment. Unlike the International Space Station (ISS), the area available for an exercise device in the next generation of spacecraft is limited. Therefore, compact resistance exercise device prototypes are being developed. The NASA Digital Astronaut Project (DAP) is supporting the Advanced Exercise Concepts (AEC) Project, Exercise Physiology and Countermeasures (ExPC) project and the National Space Biomedical Research Institute (NSBRI) funded researchers by developing computational models of exercising with these new advanced exercise device concepts. To perform validation of these models and to support the Advanced Exercise Concepts Project, several candidate devices have been flown onboard NASAs Reduced Gravity Aircraft. In terrestrial laboratories, researchers typically have available to them motion capture systems for the measurement of subject kinematics. Onboard the parabolic flight aircraft it is not practical to utilize the traditional motion capture systems due to the large working volume they require and their relatively high replacement cost if damaged. To support measuring kinematics on board parabolic aircraft, a motion capture system is being developed utilizing open source computer vision code with commercial off the shelf (COTS) video camera hardware. While the systems accuracy is lower than lab setups, it provides a means to produce quantitative comparison motion capture kinematic data. Additionally, data such as required exercise volume for small spaces such as the Orion capsule can be determined. METHODS: OpenCV is an open source computer vision library that provides the ability to perform multi-camera 3 dimensional reconstruction. Utilizing OpenCV, via the Python programming language, a set of tools has been developed to perform motion capture in confined spaces using commercial cameras. Four Sony Video Cameras were intrinsically calibrated prior to flight. Intrinsic calibration provides a set of camera specific parameters to remove geometric distortion of the lens and sensor (specific to each individual camera). A set of high contrast markers were placed on the exercising subject (safety also necessitated that they be soft in case they become detached during parabolic flight); small yarn balls were used. Extrinsic calibration, the determination of camera location and orientation parameters, is performed using fixed landmark markers shared by the camera scenes. Additionally a wand calibration, the sweeping of the camera scenes simultaneously, was also performed. Techniques have been developed to perform intrinsic calibration, extrinsic calibration, isolation of the markers in the scene, calculation of marker 2D centroids, and 3D reconstruction from multiple cameras. These methods have been tested in the laboratory side-by-side comparison to a traditional motion capture system and also on a parabolic flight.
Night vision imaging system design, integration and verification in spacecraft vacuum thermal test
NASA Astrophysics Data System (ADS)
Shang, Yonghong; Wang, Jing; Gong, Zhe; Li, Xiyuan; Pei, Yifei; Bai, Tingzhu; Zhen, Haijing
2015-08-01
The purposes of spacecraft vacuum thermal test are to characterize the thermal control systems of the spacecraft and its component in its cruise configuration and to allow for early retirement of risks associated with mission-specific and novel thermal designs. The orbit heat flux is simulating by infrared lamp, infrared cage or electric heater. As infrared cage and electric heater do not emit visible light, or infrared lamp just emits limited visible light test, ordinary camera could not operate due to low luminous density in test. Moreover, some special instruments such as satellite-borne infrared sensors are sensitive to visible light and it couldn't compensate light during test. For improving the ability of fine monitoring on spacecraft and exhibition of test progress in condition of ultra-low luminous density, night vision imaging system is designed and integrated by BISEE. System is consist of high-gain image intensifier ICCD camera, assistant luminance system, glare protect system, thermal control system and computer control system. The multi-frame accumulation target detect technology is adopted for high quality image recognition in captive test. Optical system, mechanical system and electrical system are designed and integrated highly adaptable to vacuum environment. Molybdenum/Polyimide thin film electrical heater controls the temperature of ICCD camera. The results of performance validation test shown that system could operate under vacuum thermal environment of 1.33×10-3Pa vacuum degree and 100K shroud temperature in the space environment simulator, and its working temperature is maintains at 5° during two-day test. The night vision imaging system could obtain video quality of 60lp/mm resolving power.
Handheld hyperspectral imager for standoff detection of chemical and biological aerosols
NASA Astrophysics Data System (ADS)
Hinnrichs, Michele; Jensen, James O.; McAnally, Gerard
2004-02-01
Pacific Advanced Technology has developed a small hand held imaging spectrometer, Sherlock, for gas leak and aerosol detection and imaging. The system is based on a patent technique that uses diffractive optics and image processing algorithms to detect spectral information about objects in the scene of the camera (IMSS Image Multi-spectral Sensing). This camera has been tested at Dugway Proving Ground and Dstl Porton Down facility looking at Chemical and Biological agent simulants. The camera has been used to investigate surfaces contaminated with chemical agent simulants. In addition to Chemical and Biological detection the camera has been used for environmental monitoring of green house gases and is currently undergoing extensive laboratory and field testing by the Gas Technology Institute, British Petroleum and Shell Oil for applications for gas leak detection and repair. The camera contains an embedded Power PC and a real time image processor for performing image processing algorithms to assist in the detection and identification of gas phase species in real time. In this paper we will present an over view of the technology and show how it has performed for different applications, such as gas leak detection, surface contamination, remote sensing and surveillance applications. In addition a sampling of the results form TRE field testing at Dugway in July of 2002 and Dstl at Porton Down in September of 2002 will be given.
Sensors for 3D Imaging: Metric Evaluation and Calibration of a CCD/CMOS Time-of-Flight Camera.
Chiabrando, Filiberto; Chiabrando, Roberto; Piatti, Dario; Rinaudo, Fulvio
2009-01-01
3D imaging with Time-of-Flight (ToF) cameras is a promising recent technique which allows 3D point clouds to be acquired at video frame rates. However, the distance measurements of these devices are often affected by some systematic errors which decrease the quality of the acquired data. In order to evaluate these errors, some experimental tests on a CCD/CMOS ToF camera sensor, the SwissRanger (SR)-4000 camera, were performed and reported in this paper. In particular, two main aspects are treated: the calibration of the distance measurements of the SR-4000 camera, which deals with evaluation of the camera warm up time period, the distance measurement error evaluation and a study of the influence on distance measurements of the camera orientation with respect to the observed object; the second aspect concerns the photogrammetric calibration of the amplitude images delivered by the camera using a purpose-built multi-resolution field made of high contrast targets.
Serendipitous occultations by kilometer size Kuiper Belt with MIOSOTYS
NASA Astrophysics Data System (ADS)
Doressoundiram, A.; Liu, C.-Y.; Maquet, L.; Roques, F.
2017-09-01
MIOSOTYS (Multi-object Instrument for Occultations in the SOlar system and TransitorY Systems) is a multi-fiber positioner coupled with a fast photometry camera. This is a visitor instrument mounted on the 193 cm telescope at the Observatoire de Haute-Provence, France and on the 123 cm telescope at the Calar Alto Observatory, Spain. Our immediate goal is to characterize the spatial distribution and extension of the Kuiper Belt, and the physical size distribution of TNOs. We present the observation campaigns during 2010-2013, objectives and observing strategy. We report the detection of potential candidates for occultation events of TNOs. We will discuss more specifically the method used to process the data and the modelling of diffraction patterns. We, finally present the results obtained concerning the distribution of sub-kilometer TNOs in the Kuiper Belt.
Forbes, Ruaridh; Makhija, Varun; Veyrinas, Kévin; Stolow, Albert; Lee, Jason W L; Burt, Michael; Brouard, Mark; Vallance, Claire; Wilkinson, Iain; Lausten, Rune; Hockett, Paul
2017-07-07
The Pixel-Imaging Mass Spectrometry (PImMS) camera allows for 3D charged particle imaging measurements, in which the particle time-of-flight is recorded along with (x, y) position. Coupling the PImMS camera to an ultrafast pump-probe velocity-map imaging spectroscopy apparatus therefore provides a route to time-resolved multi-mass ion imaging, with both high count rates and large dynamic range, thus allowing for rapid measurements of complex photofragmentation dynamics. Furthermore, the use of vacuum ultraviolet wavelengths for the probe pulse allows for an enhanced observation window for the study of excited state molecular dynamics in small polyatomic molecules having relatively high ionization potentials. Herein, preliminary time-resolved multi-mass imaging results from C 2 F 3 I photolysis are presented. The experiments utilized femtosecond VUV and UV (160.8 nm and 267 nm) pump and probe laser pulses in order to demonstrate and explore this new time-resolved experimental ion imaging configuration. The data indicate the depth and power of this measurement modality, with a range of photofragments readily observed, and many indications of complex underlying wavepacket dynamics on the excited state(s) prepared.
Lu, Hao; Zhao, Kaichun; Wang, Xiaochu; You, Zheng; Huang, Kaoli
2016-01-01
Bio-inspired imaging polarization navigation which can provide navigation information and is capable of sensing polarization information has advantages of high-precision and anti-interference over polarization navigation sensors that use photodiodes. Although all types of imaging polarimeters exist, they may not qualify for the research on the imaging polarization navigation algorithm. To verify the algorithm, a real-time imaging orientation determination system was designed and implemented. Essential calibration procedures for the type of system that contained camera parameter calibration and the inconsistency of complementary metal oxide semiconductor calibration were discussed, designed, and implemented. Calibration results were used to undistort and rectify the multi-camera system. An orientation determination experiment was conducted. The results indicated that the system could acquire and compute the polarized skylight images throughout the calibrations and resolve orientation by the algorithm to verify in real-time. An orientation determination algorithm based on image processing was tested on the system. The performance and properties of the algorithm were evaluated. The rate of the algorithm was over 1 Hz, the error was over 0.313°, and the population standard deviation was 0.148° without any data filter. PMID:26805851
Multi-energy SXR cameras for magnetically confined fusion plasmas (invited).
Delgado-Aparicio, L F; Maddox, J; Pablant, N; Hill, K; Bitter, M; Rice, J E; Granetz, R; Hubbard, A; Irby, J; Greenwald, M; Marmar, E; Tritz, K; Stutman, D; Stratton, B; Efthimion, P
2016-11-01
A compact multi-energy soft x-ray camera has been developed for time, energy and space-resolved measurements of the soft-x-ray emissivity in magnetically confined fusion plasmas. Multi-energy soft x-ray imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (T e , n Z , ΔZ eff , and n e,fast ). The electron temperature can be obtained by modeling the slope of the continuum radiation from ratios of the available brightness and inverted radial emissivity profiles over multiple energy ranges. Impurity density measurements are also possible using the line-emission from medium- to high-Z impurities to separate the background as well as transient levels of metal contributions. This technique should be explored also as a burning plasma diagnostic in-view of its simplicity and robustness.
Hydrogen Flame Imaging System Soars to New, Different Heights
NASA Technical Reports Server (NTRS)
2002-01-01
When Judy and Dave Duncan of Auburn, Calif.-based Duncan Technologies Inc. (DTI) developed their color hydrogen flame imaging system in the early 1990's, their market prospects were limited. 'We talked about commercializing the technology in the hydrogen community, but we also looked at commercialization on a much broader aspect. While there were some hydrogen applications, the market was not large enough to suppport an entire company; also, safety issues were a concern,' said Judy Duncan, owner and CEO of Duncan Technologies. Using the basic technology developed under the Small Business Innovation Research Program (SBIR); DTI conducted market research, identified other applications, formulated a plan for next generation development, and implemented a far-reaching marketing strategy. 'We took that technology; reinvested our own funds and energy into a second-generation design on the overall camera electronics and deployed that basic technology intially in a series of what we call multi-spectral cameras; cameras that could image in both the visible range and the infrared,' explains Duncan. 'The SBIR program allowed us to develop the technology to do a 3CCD camera, which very few compaines in the world do, particularly not small companies. The fact that we designed our own prism and specked the coding as we had for the hydrogen application, we were able to create a custom spectral configuration which could support varying types of research and applications.' As a result, Duncan Technologies Inc. of Auburn, Ca., has achieved a milestone $ 1 million in sales.
Image registration for multi-exposed HDRI and motion deblurring
NASA Astrophysics Data System (ADS)
Lee, Seok; Wey, Ho-Cheon; Lee, Seong-Deok
2009-02-01
In multi-exposure based image fusion task, alignment is an essential prerequisite to prevent ghost artifact after blending. Compared to usual matching problem, registration is more difficult when each image is captured under different photographing conditions. In HDR imaging, we use long and short exposure images, which have different brightness and there exist over/under satuated regions. In motion deblurring problem, we use blurred and noisy image pair and the amount of motion blur varies from one image to another due to the different exposure times. The main difficulty is that luminance levels of the two images are not in linear relationship and we cannot perfectly equalize or normalize the brightness of each image and this leads to unstable and inaccurate alignment results. To solve this problem, we applied probabilistic measure such as mutual information to represent similarity between images after alignment. In this paper, we discribed about the characteristics of multi-exposed input images in the aspect of registration and also analyzed the magnitude of camera hand shake. By exploiting the independence of luminance of mutual information, we proposed a fast and practically useful image registration technique in multiple capturing. Our algorithm can be applied to extreme HDR scenes and motion blurred scenes with over 90% success rate and its simplicity enables to be embedded in digital camera and mobile camera phone. The effectiveness of our registration algorithm is examined by various experiments on real HDR or motion deblurring cases using hand-held camera.
Semantic classification of business images
NASA Astrophysics Data System (ADS)
Erol, Berna; Hull, Jonathan J.
2006-01-01
Digital cameras are becoming increasingly common for capturing information in business settings. In this paper, we describe a novel method for classifying images into the following semantic classes: document, whiteboard, business card, slide, and regular images. Our method is based on combining low-level image features, such as text color, layout, and handwriting features with high-level OCR output analysis. Several Support Vector Machine Classifiers are combined for multi-class classification of input images. The system yields 95% accuracy in classification.
NASA Technical Reports Server (NTRS)
2005-01-01
KENNEDY SPACE CENTER, FLA. At Launch Pad 39B, the Orbiter Boom Sensor System (OBSS) sensor package is viewed before the orbiter's payload bay doors are closed for launch. Payload bay door closure is a significant milestone in the preparations of Discovery for the first Return to Flight mission, STS-114. This sensor package will provide surface area and depth defect inspection for all the surfaces of the orbiter. It includes an intensified television camera (ITVC) and a laser dynamic range imager, which are mounted on a pan and tilt unit, and a laser camera system (LCS) mounted on a stationary bracket. The package is part of the new safety measures added for all future Space Shuttle missions. During its 12-day mission, Discoverys seven- person crew will test new hardware and techniques to improve Shuttle safety, as well as deliver supplies to the International Space Station. Discoverys payloads include the Multi-Purpose Logistics Module Raffaello, the Lightweight Multi-Purpose Experiment Support Structure Carrier (LMC), and the External Stowage Platform-2 (ESP-2). Raffaello will deliver supplies to the International Space Station including food, clothing and research equipment. The LMC supports a replacement Control Moment Gyroscope and a tile repair sample box. The ESP-2 is outfitted with replacement parts. Launch of mission STS-114 was set for July 13 at the conclusion of the Flight Readiness Review yesterday.
Lagudi, Antonio; Bianco, Gianfranco; Muzzupappa, Maurizio; Bruno, Fabio
2016-04-14
The integration of underwater 3D data captured by acoustic and optical systems is a promising technique in various applications such as mapping or vehicle navigation. It allows for compensating the drawbacks of the low resolution of acoustic sensors and the limitations of optical sensors in bad visibility conditions. Aligning these data is a challenging problem, as it is hard to make a point-to-point correspondence. This paper presents a multi-sensor registration for the automatic integration of 3D data acquired from a stereovision system and a 3D acoustic camera in close-range acquisition. An appropriate rig has been used in the laboratory tests to determine the relative position between the two sensor frames. The experimental results show that our alignment approach, based on the acquisition of a rig in several poses, can be adopted to estimate the rigid transformation between the two heterogeneous sensors. A first estimation of the unknown geometric transformation is obtained by a registration of the two 3D point clouds, but it ends up to be strongly affected by noise and data dispersion. A robust and optimal estimation is obtained by a statistical processing of the transformations computed for each pose. The effectiveness of the method has been demonstrated in this first experimentation of the proposed 3D opto-acoustic camera.
Lagudi, Antonio; Bianco, Gianfranco; Muzzupappa, Maurizio; Bruno, Fabio
2016-01-01
The integration of underwater 3D data captured by acoustic and optical systems is a promising technique in various applications such as mapping or vehicle navigation. It allows for compensating the drawbacks of the low resolution of acoustic sensors and the limitations of optical sensors in bad visibility conditions. Aligning these data is a challenging problem, as it is hard to make a point-to-point correspondence. This paper presents a multi-sensor registration for the automatic integration of 3D data acquired from a stereovision system and a 3D acoustic camera in close-range acquisition. An appropriate rig has been used in the laboratory tests to determine the relative position between the two sensor frames. The experimental results show that our alignment approach, based on the acquisition of a rig in several poses, can be adopted to estimate the rigid transformation between the two heterogeneous sensors. A first estimation of the unknown geometric transformation is obtained by a registration of the two 3D point clouds, but it ends up to be strongly affected by noise and data dispersion. A robust and optimal estimation is obtained by a statistical processing of the transformations computed for each pose. The effectiveness of the method has been demonstrated in this first experimentation of the proposed 3D opto-acoustic camera. PMID:27089344
Preliminary analysis on faint luminous lightning events recorded by multiple high speed cameras
NASA Astrophysics Data System (ADS)
Alves, J.; Saraiva, A. V.; Pinto, O.; Campos, L. Z.; Antunes, L.; Luz, E. S.; Medeiros, C.; Buzato, T. S.
2013-12-01
The objective of this work is the study of some faint luminous events produced by lightning flashes that were recorded simultaneously by multiple high-speed cameras during the previous RAMMER (Automated Multi-camera Network for Monitoring and Study of Lightning) campaigns. The RAMMER network is composed by three fixed cameras and one mobile color camera separated by, in average, distances of 13 kilometers. They were located in the Paraiba Valley (in the cities of São José dos Campos and Caçapava), SP, Brazil, arranged in a quadrilateral shape, centered in São José dos Campos region. This configuration allowed RAMMER to see a thunderstorm from different angles, registering the same lightning flashes simultaneously by multiple cameras. Each RAMMER sensor is composed by a triggering system and a Phantom high-speed camera version 9.1, which is set to operate at a frame rate of 2,500 frames per second with a lens Nikkor (model AF-S DX 18-55 mm 1:3.5 - 5.6 G in the stationary sensors, and a lens model AF-S ED 24 mm - 1:1.4 in the mobile sensor). All videos were GPS (Global Positioning System) time stamped. For this work we used a data set collected in four RAMMER manual operation days in the campaign of 2012 and 2013. On Feb. 18th the data set is composed by 15 flashes recorded by two cameras and 4 flashes recorded by three cameras. On Feb. 19th a total of 5 flashes was registered by two cameras and 1 flash registered by three cameras. On Feb. 22th we obtained 4 flashes registered by two cameras. Finally, in March 6th two cameras recorded 2 flashes. The analysis in this study proposes an evaluation methodology for faint luminous lightning events, such as continuing current. Problems in the temporal measurement of the continuing current can generate some imprecisions during the optical analysis, therefore this work aim to evaluate the effects of distance in this parameter with this preliminary data set. In the cases that include the color camera we analyzed the RGB mode (red, green, blue) and compared them with the data provided by the black and white cameras for the same event and the influence of these parameters with the luminosity intensity of the flashes. Two peculiar cases presented, from the data obtained at one site, a stroke, some continuing current during the interval between the strokes and, then, a subsequent stroke; however, the other site showed that the subsequent stroke was in fact an M-component, since the continuing current had not vanished after its parent stroke. These events generated a dubious classification for the same event that was based only in a visual analysis with high-speed cameras and they were analyzed in this work.
The advanced linked extended reconnaissance and targeting technology demonstration project
NASA Astrophysics Data System (ADS)
Cruickshank, James; de Villers, Yves; Maheux, Jean; Edwards, Mark; Gains, David; Rea, Terry; Banbury, Simon; Gauthier, Michelle
2007-06-01
The Advanced Linked Extended Reconnaissance & Targeting (ALERT) Technology Demonstration (TD) project is addressing key operational needs of the future Canadian Army's Surveillance and Reconnaissance forces by fusing multi-sensor and tactical data, developing automated processes, and integrating beyond line-of-sight sensing. We discuss concepts for displaying and fusing multi-sensor and tactical data within an Enhanced Operator Control Station (EOCS). The sensor data can originate from the Coyote's own visible-band and IR cameras, laser rangefinder, and ground-surveillance radar, as well as beyond line-of-sight systems such as a mini-UAV and unattended ground sensors. The authors address technical issues associated with the use of fully digital IR and day video cameras and discuss video-rate image processing developed to assist the operator to recognize poorly visible targets. Automatic target detection and recognition algorithms processing both IR and visible-band images have been investigated to draw the operator's attention to possible targets. The machine generated information display requirements are presented with the human factors engineering aspects of the user interface in this complex environment, with a view to establishing user trust in the automation. The paper concludes with a summary of achievements to date and steps to project completion.
Using two MEMS deformable mirrors in an adaptive optics test bed for multiconjugate correction
NASA Astrophysics Data System (ADS)
Andrews, Jonathan R.; Martinez, Ty; Teare, Scott W.; Restaino, Sergio R.; Wilcox, Christopher C.; Santiago, Freddie; Payne, Don M.
2010-02-01
Adaptive optics systems have advanced considerably over the past decade and have become common tools for optical engineers. The most recent advances in adaptive optics technology have lead to significant reductions in the cost of most of the key components. Most significantly, the cost of deformable elements and wavefront sensor components have dropped to the point where multiple deformable mirrors and Shack- Hartmann array based wavefront sensor cameras can be included in a single system. Matched with the appropriate hardware and software, formidable systems can be operating in nearly any sized research laboratory. The significant advancement of MEMS deformable mirrors has made them very popular for use as the active corrective element in multi-conjugate adaptive optics systems so that, in particular for astronomical applications, this allows correction in more than one plane. The NRL compact AO system and atmospheric simulation systems has now been expanded to support Multi Conjugate Adaptive Optics (MCAO), taking advantage of using the liquid crystal spatial light modulator (SLM) driven aberration generators in two conjugate planes that are well separated spatially. Thus, by using two SLM based aberration generators and two separate wavefront sensors, the system can measure and apply wavefront correction with two MEMS deformable mirrors. This paper describes the multi-conjugate adaptive optics system and the testing and calibration of the system and demonstrates preliminary results with this system.
NASA Astrophysics Data System (ADS)
Anders, Niels; Suomalainen, Juha; Seeger, Manuel; Keesstra, Saskia; Bartholomeus, Harm; Paron, Paolo
2014-05-01
The recent increase of performance and endurance of electronically controlled flying platforms, such as multi-copters and fixed-wing airplanes, and decreasing size and weight of different sensors and batteries leads to increasing popularity of Unmanned Aerial Systems (UAS) for scientific purposes. Modern workflows that implement UAS include guided flight plan generation, 3D GPS navigation for fully automated piloting, and automated processing with new techniques such as "Structure from Motion" photogrammetry. UAS are often equipped with normal RGB cameras, multi- and hyperspectral sensors, radar, or other sensors, and provide a cheap and flexible solution for creating multi-temporal data sets. UAS revolutionized multi-temporal research allowing new applications related to change analysis and process monitoring. The EGU General Assembly 2014 is hosting a session on platforms, sensors and applications with UAS in soil science and geomorphology. This presentation briefly summarizes the outcome of this session, addressing the current state and future challenges of small-platform data acquisition in soil science and geomorphology.
Adding polarimetric imaging to depth map using improved light field camera 2.0 structure
NASA Astrophysics Data System (ADS)
Zhang, Xuanzhe; Yang, Yi; Du, Shaojun; Cao, Yu
2017-06-01
Polarization imaging plays an important role in various fields, especially for skylight navigation and target identification, whose imaging system is always required to be designed with high resolution, broad band, and single-lens structure. This paper describe such a imaging system based on light field 2.0 camera structure, which can calculate the polarization state and depth distance from reference plane for every objet point within a single shot. This structure, including a modified main lens, a multi-quadrants Polaroid, a honeycomb-liked micro lens array, and a high resolution CCD, is equal to an "eyes array", with 3 or more polarization imaging "glasses" in front of each "eye". Therefore, depth can be calculated by matching the relative offset of corresponding patch on neighboring "eyes", while polarization state by its relative intensity difference, and their resolution will be approximately equal to each other. An application on navigation under clear sky shows that this method has a high accuracy and strong robustness.
The Use Of Videography For Three-Dimensional Motion Analysis
NASA Astrophysics Data System (ADS)
Hawkins, D. A.; Hawthorne, D. L.; DeLozier, G. S.; Campbell, K. R.; Grabiner, M. D.
1988-02-01
Special video path editing capabilities with custom hardware and software, have been developed for use in conjunction with existing video acquisition hardware and firmware. This system has simplified the task of quantifying the kinematics of human movement. A set of retro-reflective markers are secured to a subject performing a given task (i.e. walking, throwing, swinging a golf club, etc.). Multiple cameras, a video processor, and a computer work station collect video data while the task is performed. Software has been developed to edit video files, create centroid data, and identify marker paths. Multi-camera path files are combined to form a 3D path file using the DLT method of cinematography. A separate program converts the 3D path file into kinematic data by creating a set of local coordinate axes and performing a series of coordinate transformations from one local system to the next. The kinematic data is then displayed for appropriate review and/or comparison.
NASA Astrophysics Data System (ADS)
Stoeckel, Gerhard P.; Doyle, Keith B.
2017-08-01
The Transiting Exoplanet Survey Satellite (TESS) is an instrument consisting of four, wide fieldof- view CCD cameras dedicated to the discovery of exoplanets around the brightest stars, and understanding the diversity of planets and planetary systems in our galaxy. Each camera utilizes a seven-element lens assembly with low-power and low-noise CCD electronics. Advanced multivariable optimization and numerical simulation capabilities accommodating arbitrarily complex objective functions have been added to the internally developed Lincoln Laboratory Integrated Modeling and Analysis Software (LLIMAS) and used to assess system performance. Various optical phenomena are accounted for in these analyses including full dn/dT spatial distributions in lenses and charge diffusion in the CCD electronics. These capabilities are utilized to design CCD shims for thermal vacuum chamber testing and flight, and verify comparable performance in both environments across a range of wavelengths, field points and temperature distributions. Additionally, optimizations and simulations are used for model correlation and robustness optimizations.
MuSICa at GRIS: a prototype image slicer for EST at GREGOR
NASA Astrophysics Data System (ADS)
Calcines, A.; Collados, M.; López, R. L.
2013-05-01
This communication presents a prototype image slicer for the 4-m European Solar Telescope (EST) designed for the spectrograph of the 1.5-m GREGOR solar telescope (GRIS). The design of this integral field unit has been called MuSICa (Multi-Slit Image slicer based on collimator-Camera). It is a telecentric system developed specifically for the integral field, high resolution spectrograph of EST and presents multi-slit capability, reorganizing a bidimensional field of view of 80 arcsec^{2} into 8 slits, each one of them with 200 arcsec length × 0.05 arcsec width. It minimizes the number of optical components needed to fulfil this multi-slit capability, three arrays of mirrors: slicer, collimator and camera mirror arrays (the first one flat and the other two spherical). The symmetry of the layout makes it possible to overlap the pupil images associated to each part of the sliced entrance field of view. A mask with only one circular aperture is placed at the pupil position. This symmetric characteristic offers some advantages: facilitates the manufacturing process, the alignment and reduces the costs. In addition, it is compatible with two modes of operation: spectroscopic and spectro-polarimetric, offering a great versatility. The optical quality of the system is diffraction-limited. The prototype will improve the performances of GRIS at GREGOR and is part of the feasibility study of the integral field unit for the spectrographs of EST. Although MuSICa has been designed as a solar image slicer, its concept can also be applied to night-time astronomical instruments (Collados et al. 2010, Proc. SPIE, Vol. 7733, 77330H; Collados et al. 2012, AN, 333, 901; Calcines et al. 2010, Proc. SPIE, Vol. 7735, 77351X)
First experience with THE AUTOLAP™ SYSTEM: an image-based robotic camera steering device.
Wijsman, Paul J M; Broeders, Ivo A M J; Brenkman, Hylke J; Szold, Amir; Forgione, Antonello; Schreuder, Henk W R; Consten, Esther C J; Draaisma, Werner A; Verheijen, Paul M; Ruurda, Jelle P; Kaufman, Yuval
2018-05-01
Robotic camera holders for endoscopic surgery have been available for 20 years but market penetration is low. The current camera holders are controlled by voice, joystick, eyeball tracking, or head movements, and this type of steering has proven to be successful but excessive disturbance of surgical workflow has blocked widespread introduction. The Autolap™ system (MST, Israel) uses a radically different steering concept based on image analysis. This may improve acceptance by smooth, interactive, and fast steering. These two studies were conducted to prove safe and efficient performance of the core technology. A total of 66 various laparoscopic procedures were performed with the AutoLap™ by nine experienced surgeons, in two multi-center studies; 41 cholecystectomies, 13 fundoplications including hiatal hernia repair, 4 endometriosis surgeries, 2 inguinal hernia repairs, and 6 (bilateral) salpingo-oophorectomies. The use of the AutoLap™ system was evaluated in terms of safety, image stability, setup and procedural time, accuracy of imaged-based movements, and user satisfaction. Surgical procedures were completed with the AutoLap™ system in 64 cases (97%). The mean overall setup time of the AutoLap™ system was 4 min (04:08 ± 0.10). Procedure times were not prolonged due to the use of the system when compared to literature average. The reported user satisfaction was 3.85 and 3.96 on a scale of 1 to 5 in two studies. More than 90% of the image-based movements were accurate. No system-related adverse events were recorded while using the system. Safe and efficient use of the core technology of the AutoLap™ system was demonstrated with high image stability and good surgeon satisfaction. The results support further clinical studies that will focus on usability, improved ergonomics and additional image-based features.
NASA Astrophysics Data System (ADS)
Goldstein, N.; Dressler, R. A.; Richtsmeier, S. S.; McLean, J.; Dao, P. D.; Murray-Krezan, J.; Fulcoly, D. O.
2013-09-01
Recent ground testing of a wide area camera system and automated star removal algorithms has demonstrated the potential to detect, quantify, and track deep space objects using small aperture cameras and on-board processors. The camera system, which was originally developed for a space-based Wide Area Space Surveillance System (WASSS), operates in a fixed-stare mode, continuously monitoring a wide swath of space and differentiating celestial objects from satellites based on differential motion across the field of view. It would have greatest utility in a LEO orbit to provide automated and continuous monitoring of deep space with high refresh rates, and with particular emphasis on the GEO belt and GEO transfer space. Continuous monitoring allows a concept of change detection and custody maintenance not possible with existing sensors. The detection approach is equally applicable to Earth-based sensor systems. A distributed system of such sensors, either Earth-based, or space-based, could provide automated, persistent night-time monitoring of all of deep space. The continuous monitoring provides a daily record of the light curves of all GEO objects above a certain brightness within the field of view. The daily updates of satellite light curves offers a means to identify specific satellites, to note changes in orientation and operational mode, and to queue other SSA assets for higher resolution queries. The data processing approach may also be applied to larger-aperture, higher resolution camera systems to extend the sensitivity towards dimmer objects. In order to demonstrate the utility of the WASSS system and data processing, a ground based field test was conducted in October 2012. We report here the results of the observations made at Magdalena Ridge Observatory using the prototype WASSS camera, which has a 4×60° field-of-view , <0.05° resolution, a 2.8 cm2 aperture, and the ability to view within 4° of the sun. A single camera pointed at the GEO belt provided a continuous night-long record of the intensity and location of more than 50 GEO objects detected within the camera's 60-degree field-of-view, with a detection sensitivity similar to the camera's shot noise limit of Mv=13.7. Performance is anticipated to scale with aperture area, allowing the detection of dimmer objects with larger-aperture cameras. The sensitivity of the system depends on multi-frame averaging and an image processing algorithm that exploits the different angular velocities of celestial objects and SOs. Principal Components Analysis (PCA) is used to filter out all objects moving with the velocity of the celestial frame of reference. The resulting filtered images are projected back into an Earth-centered frame of reference, or into any other relevant frame of reference, and co-added to form a series of images of the GEO objects as a function of time. The PCA approach not only removes the celestial background, but it also removes systematic variations in system calibration, sensor pointing, and atmospheric conditions. The resulting images are shot-noise limited, and can be exploited to automatically identify deep space objects, produce approximate state vectors, and track their locations and intensities as a function of time.
NASA Astrophysics Data System (ADS)
Nair, Binu M.; Diskin, Yakov; Asari, Vijayan K.
2012-10-01
We present an autonomous system capable of performing security check routines. The surveillance machine, the Clearpath Husky robotic platform, is equipped with three IP cameras with different orientations for the surveillance tasks of face recognition, human activity recognition, autonomous navigation and 3D reconstruction of its environment. Combining the computer vision algorithms onto a robotic machine has given birth to the Robust Artificial Intelligencebased Defense Electro-Robot (RAIDER). The end purpose of the RAIDER is to conduct a patrolling routine on a single floor of a building several times a day. As the RAIDER travels down the corridors off-line algorithms use two of the RAIDER's side mounted cameras to perform a 3D reconstruction from monocular vision technique that updates a 3D model to the most current state of the indoor environment. Using frames from the front mounted camera, positioned at the human eye level, the system performs face recognition with real time training of unknown subjects. Human activity recognition algorithm will also be implemented in which each detected person is assigned to a set of action classes picked to classify ordinary and harmful student activities in a hallway setting.The system is designed to detect changes and irregularities within an environment as well as familiarize with regular faces and actions to distinguish potentially dangerous behavior. In this paper, we present the various algorithms and their modifications which when implemented on the RAIDER serves the purpose of indoor surveillance.
Unattended real-time re-establishment of visibility in high dynamic range video and stills
NASA Astrophysics Data System (ADS)
Abidi, B.
2014-05-01
We describe a portable unattended persistent surveillance system that corrects for harsh illumination conditions, where bright sun light creates mixed contrast effects, i.e., heavy shadows and washouts. These effects result in high dynamic range scenes, where illuminance can vary from few luxes to a 6 figure value. When using regular monitors and cameras, such wide span of illuminations can only be visualized if the actual range of values is compressed, leading to the creation of saturated and/or dark noisy areas and a loss of information in these areas. Images containing extreme mixed contrast cannot be fully enhanced from a single exposure, simply because all information is not present in the original data. The active intervention in the acquisition process is required. A software package, capable of integrating multiple types of COTS and custom cameras, ranging from Unmanned Aerial Systems (UAS) data links to digital single-lens reflex cameras (DSLR), is described. Hardware and software are integrated via a novel smart data acquisition algorithm, which communicates to the camera the parameters that would maximize information content in the final processed scene. A fusion mechanism is then applied to the smartly acquired data, resulting in an enhanced scene where information in both dark and bright areas is revealed. Multi-threading and parallel processing are exploited to produce automatic real time full motion corrected video. A novel enhancement algorithm was also devised to process data from legacy and non-controllable cameras. The software accepts and processes pre-recorded sequences and stills, enhances visible, night vision, and Infrared data, and successfully applies to night time and dark scenes. Various user options are available, integrating custom functionalities of the application into intuitive and easy to use graphical interfaces. The ensuing increase in visibility in surveillance video and intelligence imagery will expand the performance and timely decision making of the human analyst, as well as that of unmanned systems performing automatic data exploitation, such as target detection and identification.
Multi-Image Registration for an Enhanced Vision System
NASA Technical Reports Server (NTRS)
Hines, Glenn; Rahman, Zia-Ur; Jobson, Daniel; Woodell, Glenn
2002-01-01
An Enhanced Vision System (EVS) utilizing multi-sensor image fusion is currently under development at the NASA Langley Research Center. The EVS will provide enhanced images of the flight environment to assist pilots in poor visibility conditions. Multi-spectral images obtained from a short wave infrared (SWIR), a long wave infrared (LWIR), and a color visible band CCD camera, are enhanced and fused using the Retinex algorithm. The images from the different sensors do not have a uniform data structure: the three sensors not only operate at different wavelengths, but they also have different spatial resolutions, optical fields of view (FOV), and bore-sighting inaccuracies. Thus, in order to perform image fusion, the images must first be co-registered. Image registration is the task of aligning images taken at different times, from different sensors, or from different viewpoints, so that all corresponding points in the images match. In this paper, we present two methods for registering multiple multi-spectral images. The first method performs registration using sensor specifications to match the FOVs and resolutions directly through image resampling. In the second method, registration is obtained through geometric correction based on a spatial transformation defined by user selected control points and regression analysis.
Back-illuminate fiber system research for multi-object fiber spectroscopic telescope
NASA Astrophysics Data System (ADS)
Zhou, Zengxiang; Liu, Zhigang; Hu, Hongzhuan; Wang, Jianping; Zhai, Chao; Chu, Jiaru
2016-07-01
In the telescope observation, the position of fiber will highly influence the spectra efficient input in the fiber to the spectrograph. When the fibers were back illuminated on the spectra end, they would export light on the positioner end, so the CCD cameras could capture the photo of fiber tip position covered the focal plane, calculates the precise position information by light centroid method and feeds back to control system. A set of fiber back illuminated system was developed which combined to the low revolution spectro instruments in LAMOST. It could provide uniform light output to the fibers, meet the requirements for the CCD camera measurement. The paper was introduced the back illuminated system design and different test for the light resource. After optimization, the effect illuminated system could compare with the integrating sphere, meet the conditions of fiber position measurement.Using parallel controlled fiber positioner as the spectroscopic receiver is an efficiency observation system for spectra survey, has been used in LAMOST recently, and will be proposed in CFHT and rebuilt telescope Mayall. In the telescope observation, the position of fiber will highly influence the spectra efficient input in the fiber to the spectrograph. When the fibers were back illuminated on the spectra end, they would export light on the positioner end, so the CCD cameras could capture the photo of fiber tip position covered the focal plane, calculates the precise position information by light centroid method and feeds back to control system. After many years on these research, the back illuminated fiber measurement was the best method to acquire the precision position of fibers. In LAMOST, a set of fiber back illuminated system was developed which combined to the low revolution spectro instruments in LAMOST. It could provide uniform light output to the fibers, meet the requirements for the CCD camera measurement and was controlled by high-level observation system which could shut down during the telescope observation. The paper was introduced the back illuminated system design and different test for the light resource. After optimization, the effect illuminated system could compare the integrating sphere, meet the conditions of fiber position measurement.
Non-iterative volumetric particle reconstruction near moving bodies
NASA Astrophysics Data System (ADS)
Mendelson, Leah; Techet, Alexandra
2017-11-01
When multi-camera 3D PIV experiments are performed around a moving body, the body often obscures visibility of regions of interest in the flow field in a subset of cameras. We evaluate the performance of non-iterative particle reconstruction algorithms used for synthetic aperture PIV (SAPIV) in these partially-occluded regions. We show that when partial occlusions are present, the quality and availability of 3D tracer particle information depends on the number of cameras and reconstruction procedure used. Based on these findings, we introduce an improved non-iterative reconstruction routine for SAPIV around bodies. The reconstruction procedure combines binary masks, already required for reconstruction of the body's 3D visual hull, and a minimum line-of-sight algorithm. This approach accounts for partial occlusions without performing separate processing for each possible subset of cameras. We combine this reconstruction procedure with three-dimensional imaging on both sides of the free surface to reveal multi-fin wake interactions generated by a jumping archer fish. Sufficient particle reconstruction in near-body regions is crucial to resolving the wake structures of upstream fins (i.e., dorsal and anal fins) before and during interactions with the caudal tail.
NASA Astrophysics Data System (ADS)
Al Hadhrami, Tawfik; Wang, Qi; Grecos, Christos
2012-06-01
When natural disasters or other large-scale incidents occur, obtaining accurate and timely information on the developing situation is vital to effective disaster recovery operations. High-quality video streams and high-resolution images, if available in real time, would provide an invaluable source of current situation reports to the incident management team. Meanwhile, a disaster often causes significant damage to the communications infrastructure. Therefore, another essential requirement for disaster management is the ability to rapidly deploy a flexible incident area communication network. Such a network would facilitate the transmission of real-time video streams and still images from the disrupted area to remote command and control locations. In this paper, a comprehensive end-to-end video/image transmission system between an incident area and a remote control centre is proposed and implemented, and its performance is experimentally investigated. In this study a hybrid multi-segment communication network is designed that seamlessly integrates terrestrial wireless mesh networks (WMNs), distributed wireless visual sensor networks, an airborne platform with video camera balloons, and a Digital Video Broadcasting- Satellite (DVB-S) system. By carefully integrating all of these rapidly deployable, interworking and collaborative networking technologies, we can fully exploit the joint benefits provided by WMNs, WSNs, balloon camera networks and DVB-S for real-time video streaming and image delivery in emergency situations among the disaster hit area, the remote control centre and the rescue teams in the field. The whole proposed system is implemented in a proven simulator. Through extensive simulations, the real-time visual communication performance of this integrated system has been numerically evaluated, towards a more in-depth understanding in supporting high-quality visual communications in such a demanding context.
University of Virginia suborbital infrared sensing experiment
NASA Astrophysics Data System (ADS)
Holland, Stephen; Nunnally, Clayton; Armstrong, Sarah; Laufer, Gabriel
2002-03-01
An Orion sounding rocket launched from Wallops Flight Facility carried a University of Virginia payload to an altitude of 47 km and returned infrared measurements of the Earth's upper atmosphere and video images of the ocean. The payload launch was the result of a three-year undergraduate design project by a multi-disciplinary student group from the University of Virginia and James Madison University. As part of a new multi-year design course, undergraduate students designed, built, tested, and participated in the launch of a suborbital platform from which atmospheric remote sensors and other scientific experiments could operate. The first launch included a simplified atmospheric measurement system intended to demonstrate full system operation and remote sensing capabilities during suborbital flight. A thermoelectrically cooled HgCdTe infrared detector, with peak sensitivity at 10 micrometers , measured upwelling radiation and a small camera and VCR system, aligned with the infrared sensor, provided a ground reference. Additionally, a simple orientation sensor, consisting of three photodiodes, equipped with red, green, and blue light with dichroic filters, was tested. Temperature measurements of the upper atmosphere were successfully obtained during the flight. Video images were successfully recorded on-board the payload and proved a valuable tool in the data analysis process. The photodiode system, intended as a replacement for the camera and VCR system, functioned well, despite low signal amplification. This fully integrated and flight tested payload will serve as a platform for future atmospheric sensing experiments. It is currently being modified for a second suborbital flight that will incorporate a gas filter correlation radiometry (GFCR) instrument to measure the distribution of stratospheric methane and imaging capabilities to record the chlorophyll distribution in the Metompkin Bay as an indicator of pollution runoff.
Wang, Fei; Dong, Hang; Chen, Yanan; Zheng, Nanning
2016-12-09
Strong demands for accurate non-cooperative target measurement have been arising recently for the tasks of assembling and capturing. Spherical objects are one of the most common targets in these applications. However, the performance of the traditional vision-based reconstruction method was limited for practical use when handling poorly-textured targets. In this paper, we propose a novel multi-sensor fusion system for measuring and reconstructing textureless non-cooperative spherical targets. Our system consists of four simple lasers and a visual camera. This paper presents a complete framework of estimating the geometric parameters of textureless spherical targets: (1) an approach to calibrate the extrinsic parameters between a camera and simple lasers; and (2) a method to reconstruct the 3D position of the laser spots on the target surface and achieve the refined results via an optimized scheme. The experiment results show that our proposed calibration method can obtain a fine calibration result, which is comparable to the state-of-the-art LRF-based methods, and our calibrated system can estimate the geometric parameters with high accuracy in real time.
2013-03-05
CAPE CANAVERAL, Fla. – With the help of a crane, a worker helps guide a parabolic telemetry antenna and tracker camera to the roof of the Launch Control Center, or LCC, in Launch Complex 39 at NASA's Kennedy Space Center in Florida. This antenna and camera system is the first of three that will be installed on the LCC roof for the Radio Frequency and Telemetry Station RFTS, which will be used to monitor radio frequency communications from a launch vehicle at Launch Pad 39A or B as well as provide radio frequency relay for a launch vehicle in the Vehicle Assembly Building. The RFTS replaces the shuttle-era communications and tracking labs at Kennedy. The modern RFTS checkout station is designed to primarily support NASA's Space Launch System, or SLS, and Orion spacecraft, but can support multi-user radio frequency tests as the space center transitions to support a variety of rockets and spacecraft. For more information on the modernization efforts at Kennedy, visit the Ground Systems Development and Operations, or GSDO, website at http://go.nasa.gov/groundsystems. Photo credit: NASA/Jim Grossmann
Wang, Fei; Dong, Hang; Chen, Yanan; Zheng, Nanning
2016-01-01
Strong demands for accurate non-cooperative target measurement have been arising recently for the tasks of assembling and capturing. Spherical objects are one of the most common targets in these applications. However, the performance of the traditional vision-based reconstruction method was limited for practical use when handling poorly-textured targets. In this paper, we propose a novel multi-sensor fusion system for measuring and reconstructing textureless non-cooperative spherical targets. Our system consists of four simple lasers and a visual camera. This paper presents a complete framework of estimating the geometric parameters of textureless spherical targets: (1) an approach to calibrate the extrinsic parameters between a camera and simple lasers; and (2) a method to reconstruct the 3D position of the laser spots on the target surface and achieve the refined results via an optimized scheme. The experiment results show that our proposed calibration method can obtain a fine calibration result, which is comparable to the state-of-the-art LRF-based methods, and our calibrated system can estimate the geometric parameters with high accuracy in real time. PMID:27941705
A Search for Binary Systems among the Nearest L Dwarfs
NASA Astrophysics Data System (ADS)
Reid, I. Neill; Lewitus, E.; Allen, P. R.; Cruz, Kelle L.; Burgasser, Adam J.
2006-08-01
We have used the Near-Infrared Camera and Multi-Object Spectrometer NIC1 camera on the Hubble Space Telescope to obtain high angular resolution images of 52 ultracool dwarfs in the immediate solar neighborhood. Nine systems are resolved as binary, with component separations from 1.5 to 15 AU. Based on current theoretical models and empirical bolometric corrections, all systems have components with similar luminosities and, consequently, high mass ratios, q>0.8. Limiting analysis to L dwarfs within 20 pc, the observed binary fraction is 12%+7-3. Applying Bayesian analysis to our data set, we derive a mass-ratio distribution that peaks strongly at unity. Modeling the semimajor axis distribution as a logarithmic Gaussian, the best fit is centered at loga0=0.8 AU (~6.3 AU), with a (logarithmic) width of +/-0.3. The current data are consistent with an overall binary frequency of ~24%. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.
General Astrophysics with the HabEx Workhorse Camera
NASA Astrophysics Data System (ADS)
Stern, Daniel; Clarke, John; Gaudi, B. Scott; Kiessling, Alina; Krause, Oliver; Martin, Stefan; Scowen, Paul; Somerville, Rachel; HabEx STDT
2018-01-01
The Habitable Exoplanet Imaging Mission (HabEx) concept has been designed to enable an extensive suite of science, broadly put under the rubric of General Astrophysics, in addition to its exoplanet direct imaging science. General astrophysics directly addresses multiple NASA programmatic branches, and HabEx will enable investigations ranging from cosmology, to galaxy evolution, to stellar population studies, to exoplanet transit spectroscopy, to Solar System studies. This poster briefly describes one of the two primary HabEx General Astrophysics instruments, the HabEx Workhorse Camera (HWC). HWC will be a dual-detector UV-to-near-IR imager and multi-object grism spectrometer with a microshutter array and a moderate (3' x 3') field-of-view. We detail some of the key science we expect HWC to undertake, emphasizing unique capabilities enabled by a large-aperture, highly stable space-borne platform at these wavelengths.
STS-109 Crew Interviews - Altman
NASA Technical Reports Server (NTRS)
2002-01-01
STS-109 crew Commander Scott D. Altman is seen during a prelaunch interview. He answers questions about his inspiration to become an astronaut and his career path. He gives details on the mission's goals and significance, which are all related to maintenance of the Hubble Space Telescope (HST). After the Columbia Orbiter's rendezvous with the HST, extravehicular activities (EVA) will be focused on several important tasks which include: (1) installing the Advanced Camera for Surveys; (2) installing a cooling system on NICMOS (Near Infrared Camera Multi-Object Spectrometer); (3) repairing the reaction wheel assembly; (4) installing additional solar arrays; (5) augmenting the power control unit; (6) working on the HST's gyros. The reaction wheel assembly task, a late addition to the mission, may necessitate the abandonment of one or more of the other tasks, such as the gyro work.
NASA Astrophysics Data System (ADS)
Payne, L.; Haas, J. P.; Linard, D.; White, L.
1997-12-01
The Laboratory for Astronomy and Solar Physics at Goddard Space Flight Center uses a variety imaging sensors for its instrumentation programs. This paper describes the detector system for SERTS. The SERTS rocket telescope uses an open faceplate, single plate MCP tube as the primary detector for EUV spectra from the Sun. The optical output of this detector is fiber-optically coupled to a cooled, large format CCD. This CCD is operated using a software controlled Camera controller based upon a design used for the SOHO/CDS mission. This camera is a general purpose design, with a topology that supports multiple types of imaging devices. Multiport devices (up to 4 ports) and multiphase clocks are supportable as well as variable speed operation. Clock speeds from 100KHz to 1MHz have been used, and the topology is currently being extended to support 10MHz operation. The form factor for the camera system is based on the popular VME buss. Because the tube is an open faceplate design, the detector system has an assortment of vacuum doors and plumbing to allow operation in vacuum but provide for safe storage at normal atmosphere. Vac-ion pumps (3) are used to maintain working vacuum at all times. Marshall Space Flight Center provided the SERTS programs with HVPS units for both the vac-ion pumps and the MCP tube. The MCP tube HVPS is a direct derivative of the design used for the SXI mission for NOAA. Auxiliary equipment includes a frame buffer that works either as a multi-frame storage unit or as a photon counting accumulation unit. This unit also performs interface buffering so that the camera may appear as a piece of GPIB instrumentation.
Multi-view video segmentation and tracking for video surveillance
NASA Astrophysics Data System (ADS)
Mohammadi, Gelareh; Dufaux, Frederic; Minh, Thien Ha; Ebrahimi, Touradj
2009-05-01
Tracking moving objects is a critical step for smart video surveillance systems. Despite the complexity increase, multiple camera systems exhibit the undoubted advantages of covering wide areas and handling the occurrence of occlusions by exploiting the different viewpoints. The technical problems in multiple camera systems are several: installation, calibration, objects matching, switching, data fusion, and occlusion handling. In this paper, we address the issue of tracking moving objects in an environment covered by multiple un-calibrated cameras with overlapping fields of view, typical of most surveillance setups. Our main objective is to create a framework that can be used to integrate objecttracking information from multiple video sources. Basically, the proposed technique consists of the following steps. We first perform a single-view tracking algorithm on each camera view, and then apply a consistent object labeling algorithm on all views. In the next step, we verify objects in each view separately for inconsistencies. Correspondent objects are extracted through a Homography transform from one view to the other and vice versa. Having found the correspondent objects of different views, we partition each object into homogeneous regions. In the last step, we apply the Homography transform to find the region map of first view in the second view and vice versa. For each region (in the main frame and mapped frame) a set of descriptors are extracted to find the best match between two views based on region descriptors similarity. This method is able to deal with multiple objects. Track management issues such as occlusion, appearance and disappearance of objects are resolved using information from all views. This method is capable of tracking rigid and deformable objects and this versatility lets it to be suitable for different application scenarios.
Uas for Archaeology - New Perspectives on Aerial Documentation
NASA Astrophysics Data System (ADS)
Fallavollita, P.; Balsi, M.; Esposito, S.; Melis, M. G.; Milanese, M.; Zappino, L.
2013-08-01
In this work some Unmanned Aerial Systems applications are discussed and applied to archaeological sites survey and 3D model reconstructions. Interesting results are shown for three important and different aged sites on north Sardinia (Italy). An easy and simplified procedure has proposed permitting the adoption of multi-rotor aircrafts for daily archaeological survey during excavation and documentation, involving state of art in UAS design, flight control systems, high definition sensor cameras and innovative photogrammetric software tools. Very high quality 3D models results are shown and discussed and how they have been simplified the archaeologist work and decisions.
Cryo Cooler Induced Micro-Vibration Disturbances to the Hubble Space Telescope
NASA Technical Reports Server (NTRS)
Jedrich, Nick; Zimbelman, Darrell; Turczyn, Mark; Sills, Joel; Voorhees, Carl; Clapp, Brian; Brumfield, Mark (Technical Monitor)
2002-01-01
This paper presents an overview of the Hubble Space Telescope (HST) Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cryo Cooler (MCC) system, a description of the micro-vibration characterization testing performed, and a discussion of the simulated performance. The NCC is a reverse Brayton cycle system that employs micro turbo-machinery to provide cooling to the NICMOS instrument. Extensive testing was conducted to quantify the expected on-orbit disturbances caused by the micro turbo-machinery and provide input to a flexible-body dynamic simulation to demonstrate compliance with the HST 7 milli-arcsecond root mean square jitter requirement.
Artificial neural networks and approximate reasoning for intelligent control in space
NASA Technical Reports Server (NTRS)
Berenji, Hamid R.
1991-01-01
A method is introduced for learning to refine the control rules of approximate reasoning-based controllers. A reinforcement-learning technique is used in conjunction with a multi-layer neural network model of an approximate reasoning-based controller. The model learns by updating its prediction of the physical system's behavior. The model can use the control knowledge of an experienced operator and fine-tune it through the process of learning. Some of the space domains suitable for applications of the model such as rendezvous and docking, camera tracking, and tethered systems control are discussed.
Hierarchical video surveillance architecture: a chassis for video big data analytics and exploration
NASA Astrophysics Data System (ADS)
Ajiboye, Sola O.; Birch, Philip; Chatwin, Christopher; Young, Rupert
2015-03-01
There is increasing reliance on video surveillance systems for systematic derivation, analysis and interpretation of the data needed for predicting, planning, evaluating and implementing public safety. This is evident from the massive number of surveillance cameras deployed across public locations. For example, in July 2013, the British Security Industry Association (BSIA) reported that over 4 million CCTV cameras had been installed in Britain alone. The BSIA also reveal that only 1.5% of these are state owned. In this paper, we propose a framework that allows access to data from privately owned cameras, with the aim of increasing the efficiency and accuracy of public safety planning, security activities, and decision support systems that are based on video integrated surveillance systems. The accuracy of results obtained from government-owned public safety infrastructure would improve greatly if privately owned surveillance systems `expose' relevant video-generated metadata events, such as triggered alerts and also permit query of a metadata repository. Subsequently, a police officer, for example, with an appropriate level of system permission can query unified video systems across a large geographical area such as a city or a country to predict the location of an interesting entity, such as a pedestrian or a vehicle. This becomes possible with our proposed novel hierarchical architecture, the Fused Video Surveillance Architecture (FVSA). At the high level, FVSA comprises of a hardware framework that is supported by a multi-layer abstraction software interface. It presents video surveillance systems as an adapted computational grid of intelligent services, which is integration-enabled to communicate with other compatible systems in the Internet of Things (IoT).
Get-in-the-Zone (GITZ) Transition Display Format for Changing Camera Views in Multi-UAV Operations
2008-12-01
the multi-UAV operator will witch between dynamic and static missions, each potentially involving very different scenario environments and task...another. Inspired by cinematography techniques to help audiences maintain spatial understanding of a scene across discrete film cuts, use of a
Bi, Sheng; Zeng, Xiao; Tang, Xin; Qin, Shujia; Lai, King Wai Chiu
2016-01-01
Compressive sensing (CS) theory has opened up new paths for the development of signal processing applications. Based on this theory, a novel single pixel camera architecture has been introduced to overcome the current limitations and challenges of traditional focal plane arrays. However, video quality based on this method is limited by existing acquisition and recovery methods, and the method also suffers from being time-consuming. In this paper, a multi-frame motion estimation algorithm is proposed in CS video to enhance the video quality. The proposed algorithm uses multiple frames to implement motion estimation. Experimental results show that using multi-frame motion estimation can improve the quality of recovered videos. To further reduce the motion estimation time, a block match algorithm is used to process motion estimation. Experiments demonstrate that using the block match algorithm can reduce motion estimation time by 30%. PMID:26950127
Imaging Techniques for Dense 3D reconstruction of Swimming Aquatic Life using Multi-view Stereo
NASA Astrophysics Data System (ADS)
Daily, David; Kiser, Jillian; McQueen, Sarah
2016-11-01
Understanding the movement characteristics of how various species of fish swim is an important step to uncovering how they propel themselves through the water. Previous methods have focused on profile capture methods or sparse 3D manual feature point tracking. This research uses an array of 30 cameras to automatically track hundreds of points on a fish as they swim in 3D using multi-view stereo. Blacktip sharks, sting rays, puffer fish, turtles and more were imaged in collaboration with the National Aquarium in Baltimore, Maryland using the multi-view stereo technique. The processes for data collection, camera synchronization, feature point extraction, 3D reconstruction, 3D alignment, biological considerations, and lessons learned will be presented. Preliminary results of the 3D reconstructions will be shown and future research into mathematically characterizing various bio-locomotive maneuvers will be discussed.
Multi-energy SXR cameras for magnetically confined fusion plasmas (invited)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Delgado-Aparicio, L. F.; Maddox, J.; Pablant, N.
A compact multi-energy soft x-ray camera has been developed for time, energy and space-resolved measurements of the soft-x-ray emissivity in magnetically confined fusion plasmas. Multi-energy soft x-ray imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (T e, n Z, ΔZ eff, and n e,fast). The electron temperature can be obtained by modeling the slope of the continuum radiation from ratios of the available brightness and inverted radial emissivity profiles over multiple energy ranges. Impurity density measurements are also possible using the line-emission from medium- to high-Z impurities to separate the background as well asmore » transient levels of metal contributions. As a result, this technique should be explored also as a burning plasma diagnostic in-view of its simplicity and robustness.« less
Multi-energy SXR cameras for magnetically confined fusion plasmas (invited)
Delgado-Aparicio, L. F.; Maddox, J.; Pablant, N.; ...
2016-11-14
A compact multi-energy soft x-ray camera has been developed for time, energy and space-resolved measurements of the soft-x-ray emissivity in magnetically confined fusion plasmas. Multi-energy soft x-ray imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (T e, n Z, ΔZ eff, and n e,fast). The electron temperature can be obtained by modeling the slope of the continuum radiation from ratios of the available brightness and inverted radial emissivity profiles over multiple energy ranges. Impurity density measurements are also possible using the line-emission from medium- to high-Z impurities to separate the background as well asmore » transient levels of metal contributions. As a result, this technique should be explored also as a burning plasma diagnostic in-view of its simplicity and robustness.« less
Height and Motion of the Chikurachki Eruption Plume
NASA Technical Reports Server (NTRS)
2003-01-01
The height and motion of the ash and gas plume from the April 22, 2003, eruption of the Chikurachki volcano is portrayed in these views from the Multi-angle Imaging SpectroRadiometer (MISR). Situated within the northern portion of the volcanically active Kuril Island group, the Chikurachki volcano is an active stratovolcano on Russia's Paramushir Island (just south of the Kamchatka Peninsula).In the upper panel of the still image pair, this scene is displayed as a natural-color view from MISR's vertical-viewing (nadir) camera. The white and brownish-grey plume streaks several hundred kilometers from the eastern edge of Paramushir Island toward the southeast. The darker areas of the plume typically indicate volcanic ash, while the white portions of the plume indicate entrained water droplets and ice. According to the Kamchatkan Volcanic Eruptions Response Team (KVERT), the temperature of the plume near the volcano on April 22 was -12o C.The lower panel shows heights derived from automated stereoscopic processing of MISR's multi-angle imagery, in which the plume is determined to reach heights of about 2.5 kilometers above sea level. Heights for clouds above and below the eruption plume were also retrieved, including the high-altitude cirrus clouds in the lower left (orange pixels). The distinctive patterns of these features provide sufficient spatial contrast for MISR's stereo height retrieval to perform automated feature matching between the images acquired at different view angles. Places where clouds or other factors precluded a height retrieval are shown in dark gray.The multi-angle 'fly-over' animation (below) allows the motion of the plume and of the surrounding clouds to be directly observed. The frames of the animation consist of data acquired by the 70-degree, 60-degree, 46-degree and 26-degree forward-viewing cameras in sequence, followed by the images from the nadir camera and each of the four backward-viewing cameras, ending with the view from the 70-degree backward camera.The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 17776. The panels cover an area of approximately 296 kilometers x 216 kilometers (still images) and 185 kilometers x 154 kilometers (animation), and utilize data from blocks 50 to 51 within World Reference System-2 path 100.MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology. [figure removed for brevity, see original siteUnderwater video enhancement using multi-camera super-resolution
NASA Astrophysics Data System (ADS)
Quevedo, E.; Delory, E.; Callicó, G. M.; Tobajas, F.; Sarmiento, R.
2017-12-01
Image spatial resolution is critical in several fields such as medicine, communications or satellite, and underwater applications. While a large variety of techniques for image restoration and enhancement has been proposed in the literature, this paper focuses on a novel Super-Resolution fusion algorithm based on a Multi-Camera environment that permits to enhance the quality of underwater video sequences without significantly increasing computation. In order to compare the quality enhancement, two objective quality metrics have been used: PSNR (Peak Signal-to-Noise Ratio) and the SSIM (Structural SIMilarity) index. Results have shown that the proposed method enhances the objective quality of several underwater sequences, avoiding the appearance of undesirable artifacts, with respect to basic fusion Super-Resolution algorithms.
The research on visual industrial robot which adopts fuzzy PID control algorithm
NASA Astrophysics Data System (ADS)
Feng, Yifei; Lu, Guoping; Yue, Lulin; Jiang, Weifeng; Zhang, Ye
2017-03-01
The control system of six degrees of freedom visual industrial robot based on the control mode of multi-axis motion control cards and PC was researched. For the variable, non-linear characteristics of industrial robot`s servo system, adaptive fuzzy PID controller was adopted. It achieved better control effort. In the vision system, a CCD camera was used to acquire signals and send them to video processing card. After processing, PC controls the six joints` motion by motion control cards. By experiment, manipulator can operate with machine tool and vision system to realize the function of grasp, process and verify. It has influence on the manufacturing of the industrial robot.
Design of a Multi-Sensor Cooperation Travel Environment Perception System for Autonomous Vehicle
Chen, Long; Li, Qingquan; Li, Ming; Zhang, Liang; Mao, Qingzhou
2012-01-01
This paper describes the environment perception system designed for intelligent vehicle SmartV-II, which won the 2010 Future Challenge. This system utilizes the cooperation of multiple lasers and cameras to realize several necessary functions of autonomous navigation: road curb detection, lane detection and traffic sign recognition. Multiple single scan lasers are integrated to detect the road curb based on Z-variance method. Vision based lane detection is realized by two scans method combining with image model. Haar-like feature based method is applied for traffic sign detection and SURF matching method is used for sign classification. The results of experiments validate the effectiveness of the proposed algorithms and the whole system.
Depth-tunable three-dimensional display with interactive light field control
NASA Astrophysics Data System (ADS)
Xie, Songlin; Wang, Peng; Sang, Xinzhu; Li, Chenyu; Dou, Wenhua; Xiao, Liquan
2016-07-01
A software-defined depth-tunable three-dimensional (3D) display with interactive 3D depth control is presented. With the proposed post-processing system, the disparity of the multi-view media can be freely adjusted. Benefiting from a wealth of information inherently contains in dense multi-view images captured with parallel arrangement camera array, the 3D light field is built and the light field structure is controlled to adjust the disparity without additional acquired depth information since the light field structure itself contains depth information. A statistical analysis based on the least square is carried out to extract the depth information inherently exists in the light field structure and the accurate depth information can be used to re-parameterize light fields for the autostereoscopic display, and a smooth motion parallax can be guaranteed. Experimental results show that the system is convenient and effective to adjust the 3D scene performance in the 3D display.
NASA Astrophysics Data System (ADS)
Woodruff, Robert A.; Hull, Tony; Heap, Sara R.; Danchi, William; Kendrick, Stephen E.; Purves, Lloyd
2017-09-01
We are developing a NASA Headquarters selected Probe-class mission concept called the Cosmic Evolution Through UV Spectroscopy (CETUS) mission, which includes a 1.5-m aperture diameter large field-of-view (FOV) telescope optimized for UV imaging, multi-object spectroscopy, and point-source spectroscopy. The optical system includes a Three Mirror Anastigmatic (TMA) telescope that simultaneously feeds three separate scientific instruments: the near-UV (NUV) Multi-Object Spectrograph (MOS) with a next-generation Micro-Shutter Array (MSA); the two-channel camera covering the far-UV (FUV) and NUV spectrum; and the point-source spectrograph covering the FUV and NUV region with selectable R 40,000 echelle modes and R 2,000 first order modes. The optical system includes fine guidance sensors, wavefront sensing, and spectral and flat-field in-flight calibration sources. This paper will describe the current optical design of CETUS.
NASA Astrophysics Data System (ADS)
Woodruff, Robert; Robert Woodruff, Goddard Space Flight Center, Kendrick Optical Consulting
2018-01-01
We are developing a NASA Headquarters selected Probe-class mission concept called the Cosmic Evolution Through UV Spectroscopy (CETUS) mission, which includes a 1.5-m aperture diameter large field-of-view (FOV) telescope optimized for UV imaging, multi-object spectroscopy, and point-source spectroscopy. The optical system includes a Three Mirror Anastigmatic (TMA) telescope that simultaneously feeds three separate scientific instruments: the near-UV (NUV) Multi-Object Spectrograph (MOS) with a next-generation Micro-Shutter Array (MSA); the two-channel camera covering the far-UV (FUV) and NUV spectrum; and the point-source spectrograph covering the FUV and NUV region with selectable R~ 40,000 echelle modes and R~ 2,000 first order modes. The optical system includes fine guidance sensors, wavefront sensing, and spectral and flat-field in-flight calibration sources. This paper will describe the current optical design of CETUS.
Changing the Production Pipeline - Use of Oblique Aerial Cameras for Mapping Purposes
NASA Astrophysics Data System (ADS)
Moe, K.; Toschi, I.; Poli, D.; Lago, F.; Schreiner, C.; Legat, K.; Remondino, F.
2016-06-01
This paper discusses the potential of current photogrammetric multi-head oblique cameras, such as UltraCam Osprey, to improve the efficiency of standard photogrammetric methods for surveying applications like inventory surveys and topographic mapping for public administrations or private customers. In 2015, Terra Messflug (TM), a subsidiary of Vermessung AVT ZT GmbH (Imst, Austria), has flown a number of urban areas in Austria, Czech Republic and Hungary with an UltraCam Osprey Prime multi-head camera system from Vexcel Imaging. In collaboration with FBK Trento (Italy), the data acquired at Imst (a small town in Tyrol, Austria) were analysed and processed to extract precise 3D topographic information. The Imst block comprises 780 images and covers an area of approx. 4.5 km by 1.5 km. Ground truth data is provided in the form of 6 GCPs and several check points surveyed with RTK GNSS. Besides, 3D building data obtained by photogrammetric stereo plotting from a 5 cm nadir flight and a LiDAR point cloud with 10 to 20 measurements per m² are available as reference data or for comparison. The photogrammetric workflow, from flight planning to Dense Image Matching (DIM) and 3D building extraction, is described together with the achieved accuracy. For each step, the differences and innovation with respect to standard photogrammetric procedures based on nadir images are shown, including high overlaps, improved vertical accuracy, and visibility of areas masked in the standard vertical views. Finally the advantages of using oblique images for inventory surveys are demonstrated.
BOMBOLO: a Multi-Band, Wide-field, Near UV/Optical Imager for the SOAR 4m Telescope
NASA Astrophysics Data System (ADS)
Angeloni, R.; Guzmán, D.; Puzia, T. H.; Infante, L.
2014-10-01
BOMBOLO is a new multi-passband visitor instrument for SOAR observatory. The first fully Chilean instrument of its kind, it is a three-arms imager covering the near-UV and optical wavelengths. The three arms work simultaneously and independently, providing synchronized imaging capability for rapid astronomical events. BOMBOLO will be able to address largely unexplored events in the minute-to-second timescales, with the following leading science cases: 1) Simultaneous Multiband Flickering Studies of Accretion Phenomena; 2) Near UV/Optical Diagnostics of Stellar Evolutionary Phases; 3) Exoplanetary Transits and 4) Microlensing Follow-Up. BOMBOLO optical design consists of a wide field collimator feeding two dychroics at 390 and 550 nm. Each arm encompasses a camera, filter wheel and a science CCD230-42, imaging a 7 x 7 arcmin field of view onto a 2k x 2k image. The three CCDs will have different coatings to optimise the efficiencies of each camera. The detector controller to run the three cameras will be Torrent (the NOAO open-source system) and a PanView application will run the instrument and produce the data-cubes. The instrument is at Conceptual Design stage, having been approved by the SOAR Board of Directors as a visitor instrument in 2012 and having been granted full funding from CONICYT, the Chilean State Agency of Research, in 2013. The Design Phase is starting now and will be completed in late 2014, followed by a construction phase in 2015 and 2016A, with expected Commissioning in 2016B and 2017A.
Micro-optical system based 3D imaging for full HD depth image capturing
NASA Astrophysics Data System (ADS)
Park, Yong-Hwa; Cho, Yong-Chul; You, Jang-Woo; Park, Chang-Young; Yoon, Heesun; Lee, Sang-Hun; Kwon, Jong-Oh; Lee, Seung-Wan
2012-03-01
20 Mega-Hertz-switching high speed image shutter device for 3D image capturing and its application to system prototype are presented. For 3D image capturing, the system utilizes Time-of-Flight (TOF) principle by means of 20MHz high-speed micro-optical image modulator, so called 'optical shutter'. The high speed image modulation is obtained using the electro-optic operation of the multi-layer stacked structure having diffractive mirrors and optical resonance cavity which maximizes the magnitude of optical modulation. The optical shutter device is specially designed and fabricated realizing low resistance-capacitance cell structures having small RC-time constant. The optical shutter is positioned in front of a standard high resolution CMOS image sensor and modulates the IR image reflected from the object to capture a depth image. Suggested novel optical shutter device enables capturing of a full HD depth image with depth accuracy of mm-scale, which is the largest depth image resolution among the-state-of-the-arts, which have been limited up to VGA. The 3D camera prototype realizes color/depth concurrent sensing optical architecture to capture 14Mp color and full HD depth images, simultaneously. The resulting high definition color/depth image and its capturing device have crucial impact on 3D business eco-system in IT industry especially as 3D image sensing means in the fields of 3D camera, gesture recognition, user interface, and 3D display. This paper presents MEMS-based optical shutter design, fabrication, characterization, 3D camera system prototype and image test results.
NASA Astrophysics Data System (ADS)
Goiffon, Vincent; Rolando, Sébastien; Corbière, Franck; Rizzolo, Serena; Chabane, Aziouz; Girard, Sylvain; Baer, Jérémy; Estribeau, Magali; Magnan, Pierre; Paillet, Philippe; Van Uffelen, Marco; Mont Casellas, Laura; Scott, Robin; Gaillardin, Marc; Marcandella, Claude; Marcelot, Olivier; Allanche, Timothé
2017-01-01
The Total Ionizing Dose (TID) hardness of digital color Camera-on-a-Chip (CoC) building blocks is explored in the Multi-MGy range using 60Co gamma-ray irradiations. The performances of the following CoC subcomponents are studied: radiation hardened (RH) pixel and photodiode designs, RH readout chain, Color Filter Arrays (CFA) and column RH Analog-to-Digital Converters (ADC). Several radiation hardness improvements are reported (on the readout chain and on dark current). CFAs and ADCs degradations appear to be very weak at the maximum TID of 6 MGy(SiO2), 600 Mrad. In the end, this study demonstrates the feasibility of a MGy rad-hard CMOS color digital camera-on-a-chip, illustrated by a color image captured after 6 MGy(SiO2) with no obvious degradation. An original dark current reduction mechanism in irradiated CMOS Image Sensors is also reported and discussed.
Measurement of Flat Slab Deformations by the Multi-Image Photogrammetry Method
NASA Astrophysics Data System (ADS)
Marčiš, Marián; Fraštia, Marek; Augustín, Tomáš
2017-12-01
The use of photogrammetry during load tests of building components is a common practise all over the world. It is very effective thanks to its contactless approach, 3D measurement, fast data collection, and partial or full automation of image processing; it can deliver very accurate results. Multi-image convergent photogrammetry supported by artificial coded targets is the most accurate photogrammetric method when the targets are detected in an image with a higher degree of accuracy than a 0.1 pixel. It is possible to achieve an accuracy of 0.03 mm for all the points measured on the object observed if the camera is close enough to the object, and the positions of the camera and the number of shots are precisely planned. This contribution deals with the design of a special hanging frame for a DSLR camera used during the photogrammetric measurement of the deformation of flat concrete slab. The results of the photogrammetric measurements are compared to the results from traditional contact measurement techniques during load tests.
NASA Astrophysics Data System (ADS)
Nakamura, Y.; Shimazoe, K.; Takahashi, H.; Yoshimura, S.; Seto, Y.; Kato, S.; Takahashi, M.; Momose, T.
2016-08-01
As well as pre-operative roadmapping by 18F-Fluoro-2-deoxy-2-D-glucose (FDG) positron emission tomography, intra-operative localization of the tracer is important to identify local margins for less-invasive surgery, especially FDG-guided surgery. The objective of this paper is to develop a laparoscopic Compton camera and system aimed at use for intra-operative FDG imaging for accurate and less-invasive dissections. The laparoscopic Compton camera consists of four layers of a 12-pixel cross-shaped array of GFAG crystals (2× 2× 3 mm3) and through silicon via multi-pixel photon counters and dedicated individual readout electronics based on a dynamic time-over-threshold method. Experimental results yielded a spatial resolution of 4 mm (FWHM) for a 10 mm working distance and an absolute detection efficiency of 0.11 cps kBq-1, corresponding to an intrinsic detection efficiency of ˜0.18%. In an experiment using a NEMA-like well-shaped FDG phantom, a φ 5× 10 mm cylindrical hot spot was clearly obtained even in the presence of a background distribution surrounding the Compton camera and the hot spot. We successfully obtained reconstructed images of a resected lymph node and primary tumor ex vivo after FDG administration to a patient having esophageal cancer. These performance characteristics indicate a new possibility of FDG-directed surgery by using a Compton camera intra-operatively.
Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)
NASA Astrophysics Data System (ADS)
Smee, Stephen A.; Gunn, James E.; Golebiowski, Mirek; Hope, Stephen C.; Madec, Fabrice; Gabriel, Jean-Francois; Loomis, Craig; Le fur, Arnaud; Dohlen, Kjetil; Le Mignant, David; Barkhouser, Robert; Carr, Michael; Hart, Murdock; Tamura, Naoyuki; Shimono, Atsushi; Takato, Naruhisa
2016-08-01
We describe the design and performance of the SuMIRe Prime Focus Spectrograph (PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed ground-based spectrograph consisting of four identical spectrograph modules, each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the prime focus. Each spectrograph module has three channels covering wavelength ranges 380 nm - 640 nm, 640 nm - 955 nm, and 955 nm - 1.26 um, with the dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera. The cameras are very large, having a clear aperture of 300 mm at the entrance window, and a mass of 280 kg. In this paper we describe the design of the visible camera cryostats and discuss various aspects of cryostat performance.
Hybrid Image Fusion for Sharpness Enhancement of Multi-Spectral Lunar Images
NASA Astrophysics Data System (ADS)
Awumah, Anna; Mahanti, Prasun; Robinson, Mark
2016-10-01
Image fusion enhances the sharpness of a multi-spectral (MS) image by incorporating spatial details from a higher-resolution panchromatic (Pan) image [1,2]. Known applications of image fusion for planetary images are rare, although image fusion is well-known for its applications to Earth-based remote sensing. In a recent work [3], six different image fusion algorithms were implemented and their performances were verified with images from the Lunar Reconnaissance Orbiter (LRO) Camera. The image fusion procedure obtained a high-resolution multi-spectral (HRMS) product from the LRO Narrow Angle Camera (used as Pan) and LRO Wide Angle Camera (used as MS) images. The results showed that the Intensity-Hue-Saturation (IHS) algorithm results in a high-spatial quality product while the Wavelet-based image fusion algorithm best preserves spectral quality among all the algorithms. In this work we show the results of a hybrid IHS-Wavelet image fusion algorithm when applied to LROC MS images. The hybrid method provides the best HRMS product - both in terms of spatial resolution and preservation of spectral details. Results from hybrid image fusion can enable new science and increase the science return from existing LROC images.[1] Pohl, Cle, and John L. Van Genderen. "Review article multisensor image fusion in remote sensing: concepts, methods and applications." International journal of remote sensing 19.5 (1998): 823-854.[2] Zhang, Yun. "Understanding image fusion." Photogramm. Eng. Remote Sens 70.6 (2004): 657-661.[3] Mahanti, Prasun et al. "Enhancement of spatial resolution of the LROC Wide Angle Camera images." Archives, XXIII ISPRS Congress Archives (2016).
NASA Astrophysics Data System (ADS)
Tanaka, Mio; Morita, Katsuaki; Kimura, Shigeo; Sakaue, Hirotaka
2012-11-01
Icing occurs by a collision of a supercooled-water droplet on a surface. It can be seen in any cold area. A great attention is paid in an aircraft icing. To understand the icing process on an aircraft, it is necessary to give the temperature information of the supercooled water. A conventional technique, such as a thermocouple, is not valid, because it becomes a collision surface that accumulates ice. We introduce a dual-luminescent imaging to capture a global temperature distribution of supercooled water under the icing conditions. It consists of two-color luminescent probes and a multi-band filter. One of the probes is sensitive to the temperature and the other is independent of the temperature. The latter is used to cancel the temperature-independent luminescence of a temperature-dependent image caused by an uneven illumination and a camera location. The multi-band filter only selects the luminescent peaks of the probes to enhance the temperature sensitivity of the imaging system. By applying the system, the time-resolved temperature information of a supercooled-water droplet is captured.
Situational Awareness from a Low-Cost Camera System
NASA Technical Reports Server (NTRS)
Freudinger, Lawrence C.; Ward, David; Lesage, John
2010-01-01
A method gathers scene information from a low-cost camera system. Existing surveillance systems using sufficient cameras for continuous coverage of a large field necessarily generate enormous amounts of raw data. Digitizing and channeling that data to a central computer and processing it in real time is difficult when using low-cost, commercially available components. A newly developed system is located on a combined power and data wire to form a string-of-lights camera system. Each camera is accessible through this network interface using standard TCP/IP networking protocols. The cameras more closely resemble cell-phone cameras than traditional security camera systems. Processing capabilities are built directly onto the camera backplane, which helps maintain a low cost. The low power requirements of each camera allow the creation of a single imaging system comprising over 100 cameras. Each camera has built-in processing capabilities to detect events and cooperatively share this information with neighboring cameras. The location of the event is reported to the host computer in Cartesian coordinates computed from data correlation across multiple cameras. In this way, events in the field of view can present low-bandwidth information to the host rather than high-bandwidth bitmap data constantly being generated by the cameras. This approach offers greater flexibility than conventional systems, without compromising performance through using many small, low-cost cameras with overlapping fields of view. This means significant increased viewing without ignoring surveillance areas, which can occur when pan, tilt, and zoom cameras look away. Additionally, due to the sharing of a single cable for power and data, the installation costs are lower. The technology is targeted toward 3D scene extraction and automatic target tracking for military and commercial applications. Security systems and environmental/ vehicular monitoring systems are also potential applications.
Zhang, Zutao; Li, Yanjun; Wang, Fubing; Meng, Guanjun; Salman, Waleed; Saleem, Layth; Zhang, Xiaoliang; Wang, Chunbai; Hu, Guangdi; Liu, Yugang
2016-01-01
Environmental perception and information processing are two key steps of active safety for vehicle reversing. Single-sensor environmental perception cannot meet the need for vehicle reversing safety due to its low reliability. In this paper, we present a novel multi-sensor environmental perception method using low-rank representation and a particle filter for vehicle reversing safety. The proposed system consists of four main steps, namely multi-sensor environmental perception, information fusion, target recognition and tracking using low-rank representation and a particle filter, and vehicle reversing speed control modules. First of all, the multi-sensor environmental perception module, based on a binocular-camera system and ultrasonic range finders, obtains the distance data for obstacles behind the vehicle when the vehicle is reversing. Secondly, the information fusion algorithm using an adaptive Kalman filter is used to process the data obtained with the multi-sensor environmental perception module, which greatly improves the robustness of the sensors. Then the framework of a particle filter and low-rank representation is used to track the main obstacles. The low-rank representation is used to optimize an objective particle template that has the smallest L-1 norm. Finally, the electronic throttle opening and automatic braking is under control of the proposed vehicle reversing control strategy prior to any potential collisions, making the reversing control safer and more reliable. The final system simulation and practical testing results demonstrate the validity of the proposed multi-sensor environmental perception method using low-rank representation and a particle filter for vehicle reversing safety. PMID:27294931
Zhang, Zutao; Li, Yanjun; Wang, Fubing; Meng, Guanjun; Salman, Waleed; Saleem, Layth; Zhang, Xiaoliang; Wang, Chunbai; Hu, Guangdi; Liu, Yugang
2016-06-09
Environmental perception and information processing are two key steps of active safety for vehicle reversing. Single-sensor environmental perception cannot meet the need for vehicle reversing safety due to its low reliability. In this paper, we present a novel multi-sensor environmental perception method using low-rank representation and a particle filter for vehicle reversing safety. The proposed system consists of four main steps, namely multi-sensor environmental perception, information fusion, target recognition and tracking using low-rank representation and a particle filter, and vehicle reversing speed control modules. First of all, the multi-sensor environmental perception module, based on a binocular-camera system and ultrasonic range finders, obtains the distance data for obstacles behind the vehicle when the vehicle is reversing. Secondly, the information fusion algorithm using an adaptive Kalman filter is used to process the data obtained with the multi-sensor environmental perception module, which greatly improves the robustness of the sensors. Then the framework of a particle filter and low-rank representation is used to track the main obstacles. The low-rank representation is used to optimize an objective particle template that has the smallest L-1 norm. Finally, the electronic throttle opening and automatic braking is under control of the proposed vehicle reversing control strategy prior to any potential collisions, making the reversing control safer and more reliable. The final system simulation and practical testing results demonstrate the validity of the proposed multi-sensor environmental perception method using low-rank representation and a particle filter for vehicle reversing safety.
Real-time full-motion color Flash lidar for target detection and identification
NASA Astrophysics Data System (ADS)
Nelson, Roy; Coppock, Eric; Craig, Rex; Craner, Jeremy; Nicks, Dennis; von Niederhausern, Kurt
2015-05-01
Greatly improved understanding of areas and objects of interest can be gained when real time, full-motion Flash LiDAR is fused with inertial navigation data and multi-spectral context imagery. On its own, full-motion Flash LiDAR provides the opportunity to exploit the z dimension for improved intelligence vs. 2-D full-motion video (FMV). The intelligence value of this data is enhanced when it is combined with inertial navigation data to produce an extended, georegistered data set suitable for a variety of analysis. Further, when fused with multispectral context imagery the typical point cloud now becomes a rich 3-D scene which is intuitively obvious to the user and allows rapid cognitive analysis with little or no training. Ball Aerospace has developed and demonstrated a real-time, full-motion LIDAR system that fuses context imagery (VIS to MWIR demonstrated) and inertial navigation data in real time, and can stream these information-rich geolocated/fused 3-D scenes from an airborne platform. In addition, since the higher-resolution context camera is boresighted and frame synchronized to the LiDAR camera and the LiDAR camera is an array sensor, techniques have been developed to rapidly interpolate the LIDAR pixel values creating a point cloud that has the same resolution as the context camera, effectively creating a high definition (HD) LiDAR image. This paper presents a design overview of the Ball TotalSight™ LIDAR system along with typical results over urban and rural areas collected from both rotary and fixed-wing aircraft. We conclude with a discussion of future work.
NASA Astrophysics Data System (ADS)
Abeynayake, Canicious; Chant, Ian; Kempinger, Siegfried; Rye, Alan
2005-06-01
The Rapid Route Area and Mine Neutralisation System (RRAMNS) Capability Technology Demonstrator (CTD) is a countermine detection project undertaken by DSTO and supported by the Australian Defence Force (ADF). The limited time and budget for this CTD resulted in some difficult strategic decisions with regard to hardware selection and system architecture. Although the delivered system has certain limitations arising from its experimental status, many lessons have been learned which illustrate a pragmatic path for future development. RRAMNS a similar sensor suite to other systems, in that three complementary sensors are included. These are Ground Probing Radar, Metal Detector Array, and multi-band electro-optic sensors. However, RRAMNS uses a unique imaging system and a network based real-time control and sensor fusion architecture. The relatively simple integration of each of these components could be the basis for a robust and cost-effective operational system. The RRAMNS imaging system consists of three cameras which cover the visible spectrum, the mid-wave and long-wave infrared region. This subsystem can be used separately as a scouting sensor. This paper describes the system at its mid-2004 status, when full integration of all detection components was achieved.
NASA Technical Reports Server (NTRS)
Thompson, Rodger I.
1997-01-01
Near Infrared Camera and Multi-Object Spectrometer (NICMOS) has been in orbit for about 8 months. This is a report on its current status and future plans. Also included are some comments on particular aspects of data analysis concerning dark subtraction, shading, and removal of cosmic rays. At present NICMOS provides excellent images of high scientific content. Most of the observations utilize cameras 1 and 2 which are in excellent focus. Camera 3 is not yet within the range of the focus adjustment mechanism, but its current images are still quite excellent. In this paper we will present the status of various aspects of the NICMOS instrument.
System Synchronizes Recordings from Separated Video Cameras
NASA Technical Reports Server (NTRS)
Nail, William; Nail, William L.; Nail, Jasper M.; Le, Doung T.
2009-01-01
A system of electronic hardware and software for synchronizing recordings from multiple, physically separated video cameras is being developed, primarily for use in multiple-look-angle video production. The system, the time code used in the system, and the underlying method of synchronization upon which the design of the system is based are denoted generally by the term "Geo-TimeCode(TradeMark)." The system is embodied mostly in compact, lightweight, portable units (see figure) denoted video time-code units (VTUs) - one VTU for each video camera. The system is scalable in that any number of camera recordings can be synchronized. The estimated retail price per unit would be about $350 (in 2006 dollars). The need for this or another synchronization system external to video cameras arises because most video cameras do not include internal means for maintaining synchronization with other video cameras. Unlike prior video-camera-synchronization systems, this system does not depend on continuous cable or radio links between cameras (however, it does depend on occasional cable links lasting a few seconds). Also, whereas the time codes used in prior video-camera-synchronization systems typically repeat after 24 hours, the time code used in this system does not repeat for slightly more than 136 years; hence, this system is much better suited for long-term deployment of multiple cameras.
NASA Astrophysics Data System (ADS)
Yamamoto, Naoyuki; Saito, Tsubasa; Ogawa, Satoru; Ishimaru, Ichiro
2016-05-01
We developed the palm size (optical unit: 73[mm]×102[mm]×66[mm]) and light weight (total weight with electrical controller: 1.7[kg]) middle infrared (wavelength range: 8[μm]-14[μm]) 2-dimensional spectroscopy for UAV (Unmanned Air Vehicle) like drone. And we successfully demonstrated the flights with the developed hyperspectral camera mounted on the multi-copter so-called drone in 15/Sep./2015 at Kagawa prefecture in Japan. We had proposed 2 dimensional imaging type Fourier spectroscopy that was the near-common path temporal phase-shift interferometer. We install the variable phase shifter onto optical Fourier transform plane of infinity corrected imaging optical systems. The variable phase shifter was configured with a movable mirror and a fixed mirror. The movable mirror was actuated by the impact drive piezo-electric device (stroke: 4.5[mm], resolution: 0.01[μm], maker: Technohands Co.,Ltd., type:XDT50-45, price: around 1,000USD). We realized the wavefront division type and near common path interferometry that has strong robustness against mechanical vibrations. Without anti-mechanical vibration systems, the palm-size Fourier spectroscopy was realized. And we were able to utilize the small and low-cost middle infrared camera that was the micro borometer array (un-cooled VOxMicroborometer, pixel array: 336×256, pixel pitch: 17[μm], frame rate 60[Hz], maker: FLIR, type: Quark 336, price: around 5,000USD). And this apparatus was able to be operated by single board computer (Raspberry Pi.). Thus, total cost was less than 10,000 USD. We joined with KAMOME-PJ (Kanagawa Advanced MOdule for Material Evaluation Project) with DRONE FACTORY Corp., KUUSATSU Corp., Fuji Imvac Inc. And we successfully obtained the middle infrared spectroscopic imaging with multi-copter drone.
Linear CCD attitude measurement system based on the identification of the auxiliary array CCD
NASA Astrophysics Data System (ADS)
Hu, Yinghui; Yuan, Feng; Li, Kai; Wang, Yan
2015-10-01
Object to the high precision flying target attitude measurement issues of a large space and large field of view, comparing existing measurement methods, the idea is proposed of using two array CCD to assist in identifying the three linear CCD with multi-cooperative target attitude measurement system, and to address the existing nonlinear system errors and calibration parameters and more problems with nine linear CCD spectroscopic test system of too complicated constraints among camera position caused by excessive. The mathematical model of binocular vision and three linear CCD test system are established, co-spot composition triangle utilize three red LED position light, three points' coordinates are given in advance by Cooperate Measuring Machine, the red LED in the composition of the three sides of a triangle adds three blue LED light points as an auxiliary, so that array CCD is easier to identify three red LED light points, and linear CCD camera is installed of a red filter to filter out the blue LED light points while reducing stray light. Using array CCD to measure the spot, identifying and calculating the spatial coordinates solutions of red LED light points, while utilizing linear CCD to measure three red LED spot for solving linear CCD test system, which can be drawn from 27 solution. Measured with array CCD coordinates auxiliary linear CCD has achieved spot identification, and has solved the difficult problems of multi-objective linear CCD identification. Unique combination of linear CCD imaging features, linear CCD special cylindrical lens system is developed using telecentric optical design, the energy center of the spot position in the depth range of convergence in the direction is perpendicular to the optical axis of the small changes ensuring highprecision image quality, and the entire test system improves spatial object attitude measurement speed and precision.
HALO: a reconfigurable image enhancement and multisensor fusion system
NASA Astrophysics Data System (ADS)
Wu, F.; Hickman, D. L.; Parker, Steve J.
2014-06-01
Contemporary high definition (HD) cameras and affordable infrared (IR) imagers are set to dramatically improve the effectiveness of security, surveillance and military vision systems. However, the quality of imagery is often compromised by camera shake, or poor scene visibility due to inadequate illumination or bad atmospheric conditions. A versatile vision processing system called HALO™ is presented that can address these issues, by providing flexible image processing functionality on a low size, weight and power (SWaP) platform. Example processing functions include video distortion correction, stabilisation, multi-sensor fusion and image contrast enhancement (ICE). The system is based around an all-programmable system-on-a-chip (SoC), which combines the computational power of a field-programmable gate array (FPGA) with the flexibility of a CPU. The FPGA accelerates computationally intensive real-time processes, whereas the CPU provides management and decision making functions that can automatically reconfigure the platform based on user input and scene content. These capabilities enable a HALO™ equipped reconnaissance or surveillance system to operate in poor visibility, providing potentially critical operational advantages in visually complex and challenging usage scenarios. The choice of an FPGA based SoC is discussed, and the HALO™ architecture and its implementation are described. The capabilities of image distortion correction, stabilisation, fusion and ICE are illustrated using laboratory and trials data.
Natural 3D content on glasses-free light-field 3D cinema
NASA Astrophysics Data System (ADS)
Balogh, Tibor; Nagy, Zsolt; Kovács, Péter Tamás.; Adhikarla, Vamsi K.
2013-03-01
This paper presents a complete framework for capturing, processing and displaying the free viewpoint video on a large scale immersive light-field display. We present a combined hardware-software solution to visualize free viewpoint 3D video on a cinema-sized screen. The new glasses-free 3D projection technology can support larger audience than the existing autostereoscopic displays. We introduce and describe our new display system including optical and mechanical design considerations, the capturing system and render cluster for producing the 3D content, and the various software modules driving the system. The indigenous display is first of its kind, equipped with front-projection light-field HoloVizio technology, controlling up to 63 MP. It has all the advantages of previous light-field displays and in addition, allows a more flexible arrangement with a larger screen size, matching cinema or meeting room geometries, yet simpler to set-up. The software system makes it possible to show 3D applications in real-time, besides the natural content captured from dense camera arrangements as well as from sparse cameras covering a wider baseline. Our software system on the GPU accelerated render cluster, can also visualize pre-recorded Multi-view Video plus Depth (MVD4) videos on this light-field glasses-free cinema system, interpolating and extrapolating missing views.
IPS - a vision aided navigation system
NASA Astrophysics Data System (ADS)
Börner, Anko; Baumbach, Dirk; Buder, Maximilian; Choinowski, Andre; Ernst, Ines; Funk, Eugen; Grießbach, Denis; Schischmanow, Adrian; Wohlfeil, Jürgen; Zuev, Sergey
2017-04-01
Ego localization is an important prerequisite for several scientific, commercial, and statutory tasks. Only by knowing one's own position, can guidance be provided, inspections be executed, and autonomous vehicles be operated. Localization becomes challenging if satellite-based navigation systems are not available, or data quality is not sufficient. To overcome this problem, a team of the German Aerospace Center (DLR) developed a multi-sensor system based on the human head and its navigation sensors - the eyes and the vestibular system. This system is called integrated positioning system (IPS) and contains a stereo camera and an inertial measurement unit for determining an ego pose in six degrees of freedom in a local coordinate system. IPS is able to operate in real time and can be applied for indoor and outdoor scenarios without any external reference or prior knowledge. In this paper, the system and its key hardware and software components are introduced. The main issues during the development of such complex multi-sensor measurement systems are identified and discussed, and the performance of this technology is demonstrated. The developer team started from scratch and transfers this technology into a commercial product right now. The paper finishes with an outlook.
CATAVIÑA: new infrared camera for OAN-SPM
NASA Astrophysics Data System (ADS)
Iriarte, Arturo; Cruz-González, Irene; Martínez, Luis A.; Tinoco, Silvio; Lara, Gerardo; Ruiz, Elfego; Sohn, Erika; Bernal, Abel; Angeles, Fernando; Moreno, Arturo; Murillo, Francisco; Langarica, Rosalía; Luna, Esteban; Salas, Luis; Cajero, Vicente
2006-06-01
CATAVIÑA is a near-infrared camera system to be operated in conjunction with the existing multi-purpose nearinfrared optical bench "CAMALEON" in OAN-SPM. Observing modes include direct imaging, spectroscopy, Fabry- Perot interferometry and polarimetry. This contribution focuses on the optomechanics and detector controller description of CATAVIÑA, which is planned to start operating later in 2006. The camera consists of an 8 inch LN2 dewar containing a 10 filter carousel, a radiation baffle and the detector circuit board mount. The system is based on a Rockwell 1024x1024 HgCdTe (HAWAII-I) FPA, operating in the 1 to 2.5 micron window. The detector controller/readout system was designed and developed at UNAM Instituto de Astronomia. It is based on five Texas Instruments DSK digital signal processor (DSP) modules. One module generates the detector and ADC-system control, while the remaining four are in charge of the acquisition of each of the detector's quadrants. Each DSP has a built-in expanded memory module in order to store more than one image. The detector read-out and signal driver subsystems are mounted onto the dewar in a "back-pack" fashion, each containing four independent pre-amplifiers, converters and signal drivers, that communicate through fiber optics with their respective DSPs. This system has the possibility of programming the offset input voltage and converter gain. The controller software architecture is based on a client/server model. The client sends commands through the TCP/IP protocol and acquires the image. The server consists of a microcomputer with an embedded Linux operating system, which runs the main program that receives the user commands and interacts with the timing and acquisition DSPs. The observer's interface allows for several readout and image processing modes.
STS-109 Onboard Photo of Extra-Vehicular Activity (EVA)
NASA Technical Reports Server (NTRS)
2002-01-01
This is an onboard photo of the Hubble Space Telescope (HST) power control unit (PCU), the heart of the HST's power system. STS-109 payload commander John M. Grunsfeld, joined by Astronaut Richard M. Lirnehan, turned off the telescope in order to replace its PCU while participating in the third of five spacewalks dedicated to servicing and upgrading the HST. Other upgrades performed were: replacement of the solar array panels; replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where crew members completed the system upgrades. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.
2002-03-01
This is an onboard photo of the Hubble Space Telescope (HST) power control unit (PCU), the heart of the HST's power system. STS-109 payload commander John M. Grunsfeld, joined by Astronaut Richard M. Lirnehan, turned off the telescope in order to replace its PCU while participating in the third of five spacewalks dedicated to servicing and upgrading the HST. Other upgrades performed were: replacement of the solar array panels; replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-Object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The telescope was captured and secured on a work stand in Columbia's payload bay using Columbia's robotic arm, where crew members completed the system upgrades. The Marshall Space Flight Center had the responsibility for the design, development, and construction of the HST, which is the most complex and sensitive optical telescope ever made, to study the cosmos from a low-Earth orbit. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. Launched March 1, 2002 the STS-109 HST servicing mission lasted 10 days, 22 hours, and 11 minutes. It was the 108th flight overall in NASA's Space Shuttle Program.
Performance Assessment and Geometric Calibration of RESOURCESAT-2
NASA Astrophysics Data System (ADS)
Radhadevi, P. V.; Solanki, S. S.; Akilan, A.; Jyothi, M. V.; Nagasubramanian, V.
2016-06-01
Resourcesat-2 (RS-2) has successfully completed five years of operations in its orbit. This satellite has multi-resolution and multi-spectral capabilities in a single platform. A continuous and autonomous co-registration, geo-location and radiometric calibration of image data from different sensors with widely varying view angles and resolution was one of the challenges of RS-2 data processing. On-orbit geometric performance of RS-2 sensors has been widely assessed and calibrated during the initial phase operations. Since then, as an ongoing activity, various geometric performance data are being generated periodically. This is performed with sites of dense ground control points (GCPs). These parameters are correlated to the direct geo-location accuracy of the RS-2 sensors and are monitored and validated to maintain the performance. This paper brings out the geometric accuracy assessment, calibration and validation done for about 500 datasets of RS-2. The objectives of this study are to ensure the best absolute and relative location accuracy of different cameras, location performance with payload steering and co-registration of multiple bands. This is done using a viewing geometry model, given ephemeris and attitude data, precise camera geometry and datum transformation. In the model, the forward and reverse transformations between the coordinate systems associated with the focal plane, payload, body, orbit and ground are rigorously and explicitly defined. System level tests using comparisons to ground check points have validated the operational geo-location accuracy performance and the stability of the calibration parameters.
Retinal oxygen saturation evaluation by multi-spectral fundus imaging
NASA Astrophysics Data System (ADS)
Khoobehi, Bahram; Ning, Jinfeng; Puissegur, Elise; Bordeaux, Kimberly; Balasubramanian, Madhusudhanan; Beach, James
2007-03-01
Purpose: To develop a multi-spectral method to measure oxygen saturation of the retina in the human eye. Methods: Five Cynomolgus monkeys with normal eyes were anesthetized with intramuscular ketamine/xylazine and intravenous pentobarbital. Multi-spectral fundus imaging was performed in five monkeys with a commercial fundus camera equipped with a liquid crystal tuned filter in the illumination light path and a 16-bit digital camera. Recording parameters were controlled with software written specifically for the application. Seven images at successively longer oxygen-sensing wavelengths were recorded within 4 seconds. Individual images for each wavelength were captured in less than 100 msec of flash illumination. Slightly misaligned images of separate wavelengths due to slight eye motion were registered and corrected by translational and rotational image registration prior to analysis. Numerical values of relative oxygen saturation of retinal arteries and veins and the underlying tissue in between the artery/vein pairs were evaluated by an algorithm previously described, but which is now corrected for blood volume from averaged pixels (n > 1000). Color saturation maps were constructed by applying the algorithm at each image pixel using a Matlab script. Results: Both the numerical values of relative oxygen saturation and the saturation maps correspond to the physiological condition, that is, in a normal retina, the artery is more saturated than the tissue and the tissue is more saturated than the vein. With the multi-spectral fundus camera and proper registration of the multi-wavelength images, we were able to determine oxygen saturation in the primate retinal structures on a tolerable time scale which is applicable to human subjects. Conclusions: Seven wavelength multi-spectral imagery can be used to measure oxygen saturation in retinal artery, vein, and tissue (microcirculation). This technique is safe and can be used to monitor oxygen uptake in humans. This work is original and is not under consideration for publication elsewhere.
Winter precipitation particle size distribution measurement by Multi-Angle Snowflake Camera
NASA Astrophysics Data System (ADS)
Huang, Gwo-Jong; Kleinkort, Cameron; Bringi, V. N.; Notaroš, Branislav M.
2017-12-01
From the radar meteorology viewpoint, the most important properties for quantitative precipitation estimation of winter events are 3D shape, size, and mass of precipitation particles, as well as the particle size distribution (PSD). In order to measure these properties precisely, optical instruments may be the best choice. The Multi-Angle Snowflake Camera (MASC) is a relatively new instrument equipped with three high-resolution cameras to capture the winter precipitation particle images from three non-parallel angles, in addition to measuring the particle fall speed using two pairs of infrared motion sensors. However, the results from the MASC so far are usually presented as monthly or seasonally, and particle sizes are given as histograms, no previous studies have used the MASC for a single storm study, and no researchers use MASC to measure the PSD. We propose the methodology for obtaining the winter precipitation PSD measured by the MASC, and present and discuss the development, implementation, and application of the new technique for PSD computation based on MASC images. Overall, this is the first study of the MASC-based PSD. We present PSD MASC experiments and results for segments of two snow events to demonstrate the performance of our PSD algorithm. The results show that the self-consistency of the MASC measured single-camera PSDs is good. To cross-validate PSD measurements, we compare MASC mean PSD (averaged over three cameras) with the collocated 2D Video Disdrometer, and observe good agreements of the two sets of results.
Metrology Camera System Using Two-Color Interferometry
NASA Technical Reports Server (NTRS)
Dubovitsky, Serge; Liebe, Carl Christian; Peters, Robert; Lay, Oliver
2007-01-01
A metrology system that contains no moving parts simultaneously measures the bearings and ranges of multiple reflective targets in its vicinity, enabling determination of the three-dimensional (3D) positions of the targets with submillimeter accuracy. The system combines a direction-measuring metrology camera and an interferometric range-finding subsystem. Because the system is based partly on a prior instrument denoted the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor and because of its 3D capability, the system is denoted the MSTAR3D. Developed for use in measuring the shape (for the purpose of compensating for distortion) of large structures like radar antennas, it can also be used to measure positions of multiple targets in the course of conventional terrestrial surveying. A diagram of the system is shown in the figure. One of the targets is a reference target having a known, constant distance with respect to the system. The system comprises a laser for generating local and target beams at a carrier frequency; a frequency shifting unit to introduce a frequency shift offset between the target and local beams; a pair of high-speed modulators that apply modulation to the carrier frequency in the local and target beams to produce a series of modulation sidebands, the highspeed modulators having modulation frequencies of FL and FM; a target beam launcher that illuminates the targets with the target beam; optics and a multipixel photodetector; a local beam launcher that launches the local beam towards the multi-pixel photodetector; a mirror for projecting to the optics a portion of the target beam reflected from the targets, the optics being configured to focus the portion of the target beam at the multi-pixel photodetector; and a signal-processing unit connected to the photodetector. The portion of the target beam reflected from the targets produces spots on the multi-pixel photodetector corresponding to the targets, respectively, and the signal-processing unit centroids the spots to determine bearings of the targets, respectively. As the spots oscillate in intensity because they are mixed with the local laser beam that is flood illuminating the focal plane, the phase of oscillation of each spot is measured, the phase of sidebands in the oscillation of each spot being proportional to a distance to the corresponding target relative to the reference target A.
2009-05-08
CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' payload bay is filled with hardware for the STS-125 mission to service NASA's Hubble Space Telescope. From the bottom are the Flight Support System with the Soft Capture mechanism and Multi-Use Lightweight Equipment Carrier with the Science Instrument Command and Data Handling Unit, or SIC&DH; the Orbital Replacement Unit Carrier with the Cosmic Origins Spectrograph, or COS, and an IMAX 3D camera; and the Super Lightweight Interchangeable Carrier with the Wide Field Camera 3. Atlantis' crew will service NASA's Hubble Space Telescope for the fifth and final time. The flight will include five spacewalks during which astronauts will refurbish and upgrade the telescope with state-of-the-art science instruments. As a result, Hubble's capabilities will be expanded and its operational lifespan extended through at least 2014. Photo credit: NASA/Kim Shiflett
2009-05-08
CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' payload bay is filled with hardware for the STS-125 mission to service NASA's Hubble Space Telescope. At the bottom are the Flight Support System with the Soft Capture mechanism and Multi-Use Lightweight Equipment Carrier with the Science Instrument Command and Data Handling Unit, or SIC&DH. At center is the Orbital Replacement Unit Carrier with the Cosmic Origins Spectrograph, or COS, and an IMAX 3D camera. At top is the Super Lightweight Interchangeable Carrier with the Wide Field Camera 3. Atlantis' crew will service NASA's Hubble Space Telescope for the fifth and final time. The flight will include five spacewalks during which astronauts will refurbish and upgrade the telescope with state-of-the-art science instruments. As a result, Hubble's capabilities will be expanded and its operational lifespan extended through at least 2014. Photo credit: NASA/Kim Shiflett
2009-05-08
CAPE CANAVERAL, Fla. – On Launch Pad 39A at NASA's Kennedy Space Center in Florida, space shuttle Atlantis' payload bay is filled with hardware for the STS-125 mission to service NASA's Hubble Space Telescope. From the bottom are the Flight Support System with the Soft Capture mechanism and Multi-Use Lightweight Equipment Carrier with the Science Instrument Command and Data Handling Unit, or SIC&DH. At center is the Orbital Replacement Unit Carrier with the Cosmic Origins Spectrograph, or COS, and an IMAX 3D camera. At top is the Super Lightweight Interchangeable Carrier with the Wide Field Camera 3. Atlantis' crew will service NASA's Hubble Space Telescope for the fifth and final time. The flight will include five spacewalks during which astronauts will refurbish and upgrade the telescope with state-of-the-art science instruments. As a result, Hubble's capabilities will be expanded and its operational lifespan extended through at least 2014. Photo credit: NASA/Kim Shiflett
STS-109 Crew Interviews - Currie
NASA Technical Reports Server (NTRS)
2002-01-01
STS-109 Mission Specialist 2 Nancy Jane Currie is seen during a prelaunch interview. She answers questions about her inspiration to become an astronaut and her career path. She gives details on the Columbia Orbiter mission which has as its main tasks the maintenance and augmentation of the Hubble Space Telescope (HST). While she will do many things during the mission, the most important will be her role as the primary operator of the robotic arm, which is responsible for grappling the HST, bringing it to the Orbiter bay, and providing support for the astronauts during their EVAs (Extravehicular Activities). Additionally, the robotic arm will be responsible for transferring new and replacement equipment from the Orbiter to the HST. This equipment includes: two solar arrays, a Power Control Unit (PCU), the Advanced Camera for Surveys, and a replacement cooling system for NICMOS (Near Infrared Camera Multi-Object Spectrometer).
NASA Astrophysics Data System (ADS)
Aspden, Reuben S.; Tasca, Daniel S.; Forbes, Andrew; Boyd, Robert W.; Padgett, Miles J.
2014-04-01
The Klyshko advanced-wave picture is a well-known tool useful in the conceptualisation of parametric down-conversion (SPDC) experiments. Despite being well-known and understood, there have been few experimental demonstrations illustrating its validity. Here, we present an experimental demonstration of this picture using a time-gated camera in an image-based coincidence measurement. We show an excellent agreement between the spatial distributions as predicted by the Klyshko picture and those obtained using the SPDC photon pairs. An interesting speckle feature is present in the Klyshko predictive images due to the spatial coherence of the back-propagated beam in the multi-mode fibre. This effect can be removed by mechanically twisting the fibre, thus degrading the spatial coherence of the beam and time-averaging the speckle pattern, giving an accurate correspondence between the predictive and SPDC images.
Astronomers Find Elusive Planets in Decade-Old Hubble Data
2017-12-08
NASA image release Oct. 6, 2011 This is an image of the star HR 8799 taken by Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) in 1998. A mask within the camera (coronagraph) blocks most of the light from the star. In addition, software has been used to digitally subtract more starlight. Nevertheless, scattered light from HR 8799 dominates the image, obscuring the faint planets. Object Name: HR 8799 Image Type: Astronomical Credit: NASA, ESA, and R. Soummer (STScI) To read more go to: www.nasa.gov/mission_pages/hubble/science/elusive-planets... NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram
NASA Astrophysics Data System (ADS)
Baker, B.; Lee, T.; Buban, M.; Dumas, E. J.
2017-12-01
Evaluation of Unmanned Aircraft Systems (UAS) for Weather and Climate using the Multi-testbed approachC. Bruce Baker1, Ed Dumas1,2, Temple Lee1,2, Michael Buban1,21NOAA ARL, Atmospheric Turbulence and Diffusion Division, Oak Ridge, TN2Oak Ridge Associated Universities, Oak Ridge, TN The development of a small Unmanned Aerial System (sUAS) testbeds that can be used to validate, integrate, calibrate and evaluate new technology and sensors for routine boundary layer research, validation of operational weather models, improvement of model parameterizations, and recording observations within high-impact storms is important for understanding the importance and impact of using sUAS's routinely as a new observing platform. The goal of the multi-testbed approach is to build a robust set of protocols to assess the cost and operational feasibility of unmanned observations for routine applications using various combinations of sUAS aircraft and sensors in different locations and field experiments. All of these observational testbeds serve different community needs, but they also use a diverse suite of methodologies for calibration and evaluation of different sensors and platforms for severe weather and boundary layer research. The primary focus will be to evaluate meteorological sensor payloads to measure thermodynamic parameters and define surface characteristics with visible, IR, and multi-spectral cameras. This evaluation will lead to recommendations for sensor payloads for VTOL and fixed-wing sUAS.
The Status of the NASA All Sky Fireball Network
NASA Technical Reports Server (NTRS)
Cooke, William J.; Moser, Danielle E.
2011-01-01
Established by the NASA Meteoroid Environment Office, the NASA All Sky Fireball Network consists of 6 meteor video cameras in the southern United States, with plans to expand to 15 cameras by 2013. As of mid-2011, the network had detected 1796 multi-station meteors, including meteors from 43 different meteor showers. The current status of the NASA All Sky Fireball Network is described, alongside preliminary results.
Camera-Model Identification Using Markovian Transition Probability Matrix
NASA Astrophysics Data System (ADS)
Xu, Guanshuo; Gao, Shang; Shi, Yun Qing; Hu, Ruimin; Su, Wei
Detecting the (brands and) models of digital cameras from given digital images has become a popular research topic in the field of digital forensics. As most of images are JPEG compressed before they are output from cameras, we propose to use an effective image statistical model to characterize the difference JPEG 2-D arrays of Y and Cb components from the JPEG images taken by various camera models. Specifically, the transition probability matrices derived from four different directional Markov processes applied to the image difference JPEG 2-D arrays are used to identify statistical difference caused by image formation pipelines inside different camera models. All elements of the transition probability matrices, after a thresholding technique, are directly used as features for classification purpose. Multi-class support vector machines (SVM) are used as the classification tool. The effectiveness of our proposed statistical model is demonstrated by large-scale experimental results.
The Multi-site All-Sky CAmeRA (MASCARA). Finding transiting exoplanets around bright (mV < 8) stars
NASA Astrophysics Data System (ADS)
Talens, G. J. J.; Spronck, J. F. P.; Lesage, A.-L.; Otten, G. P. P. L.; Stuik, R.; Pollacco, D.; Snellen, I. A. G.
2017-05-01
This paper describes the design, operations, and performance of the Multi-site All-Sky CAmeRA (MASCARA). Its primary goal is to find new exoplanets transiting bright stars, 4 < mV < 8, by monitoring the full sky. MASCARA consists of one northern station on La Palma, Canary Islands (fully operational since February 2015), one southern station at La Silla Observatory, Chile (operational from early 2017), and a data centre at Leiden Observatory in the Netherlands. Both MASCARA stations are equipped with five interline CCD cameras using wide field lenses (24 mm focal length) with fixed pointings, which together provide coverage down to airmass 3 of the local sky. The interline CCD cameras allow for back-to-back exposures, taken at fixed sidereal times with exposure times of 6.4 sidereal seconds. The exposures are short enough that the motion of stars across the CCD does not exceed one pixel during an integration. Astrometry and photometry are performed on-site, after which the resulting light curves are transferred to Leiden for further analysis. The final MASCARA archive will contain light curves for 70 000 stars down to mV = 8.4, with a precision of 1.5% per 5 minutes at mV = 8.
GPS/Optical/Inertial Integration for 3D Navigation Using Multi-Copter Platforms
NASA Technical Reports Server (NTRS)
Dill, Evan T.; Young, Steven D.; Uijt De Haag, Maarten
2017-01-01
In concert with the continued advancement of a UAS traffic management system (UTM), the proposed uses of autonomous unmanned aerial systems (UAS) have become more prevalent in both the public and private sectors. To facilitate this anticipated growth, a reliable three-dimensional (3D) positioning, navigation, and mapping (PNM) capability will be required to enable operation of these platforms in challenging environments where global navigation satellite systems (GNSS) may not be available continuously. Especially, when the platform's mission requires maneuvering through different and difficult environments like outdoor opensky, outdoor under foliage, outdoor-urban and indoor, and may include transitions between these environments. There may not be a single method to solve the PNM problem for all environments. The research presented in this paper is a subset of a broader research effort, described in [1]. The research is focused on combining data from dissimilar sensor technologies to create an integrated navigation and mapping method that can enable reliable operation in both an outdoor and structured indoor environment. The integrated navigation and mapping design is utilizes a Global Positioning System (GPS) receiver, an Inertial Measurement Unit (IMU), a monocular digital camera, and three short to medium range laser scanners. This paper describes specifically the techniques necessary to effectively integrate the monocular camera data within the established mechanization. To evaluate the developed algorithms a hexacopter was built, equipped with the discussed sensors, and both hand-carried and flown through representative environments. This paper highlights the effect that the monocular camera has on the aforementioned sensor integration scheme's reliability, accuracy and availability.
Airborne camera and spectrometer experiments and data evaluation
NASA Astrophysics Data System (ADS)
Lehmann, F. F.; Bucher, T.; Pless, S.; Wohlfeil, J.; Hirschmüller, H.
2009-09-01
New stereo push broom camera systems have been developed at German Aerospace Centre (DLR). The new small multispectral systems (Multi Functional Camerahead - MFC, Advanced Multispectral Scanner - AMS) are light weight, compact and display three or five RGB stereo lines of 8000, 10 000 or 14 000 pixels, which are used for stereo processing and the generation of Digital Surface Models (DSM) and near True Orthoimage Mosaics (TOM). Simultaneous acquisition of different types of MFC-cameras for infrared and RGB data has been successfully tested. All spectral channels record the image data in full resolution, pan-sharpening is not necessary. Analogue to the line scanner data an automatic processing chain for UltraCamD and UltraCamX exists. The different systems have been flown for different types of applications; main fields of interest among others are environmental applications (flooding simulations, monitoring tasks, classification) and 3D-modelling (e.g. city mapping). From the DSM and TOM data Digital Terrain Models (DTM) and 3D city models are derived. Textures for the facades are taken from oblique orthoimages, which are created from the same input data as the TOM and the DOM. The resulting models are characterised by high geometric accuracy and the perfect fit of image data and DSM. The DLR is permanently developing and testing a wide range of sensor types and imaging platforms for terrestrial and space applications. The MFC-sensors have been flown in combination with laser systems and imaging spectrometers and special data fusion products have been developed. These products include hyperspectral orthoimages and 3D hyperspectral data.
2002-01-17
KENNEDY SPACE CENTER, FLA. -- Workers in the Vertical Processing Facility look over the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. NICMOS is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002
2002-01-17
KENNEDY SPACE CENTER, FLA. -- A closeup view of the Near Infrared Camera and Multi-Object Spectrometer (NICMOS) Cooling System, part of the payload on mission STS-109, the Hubble Servicing Telescope Mission. NICMOS II is a new experimental cooling system consisting of a compressor and tiny turbines. With the experimental cryogenic system, NASA hopes to re-cool the infrared detectors to below -315 degrees F (-193 degrees Celsius). NICMOS II was previously tested aboard STS-95 in 1998. It could extend the life of the Hubble Space Telescope by several years. Astronauts aboard Columbia on mission STS-109 will be replacing the original NICMOS with the newer version. Launch of mission STS-109 is scheduled for Feb. 28, 2002
Camera network video summarization
NASA Astrophysics Data System (ADS)
Panda, Rameswar; Roy-Chowdhury, Amit K.
2017-05-01
Networks of vision sensors are deployed in many settings, ranging from security needs to disaster response to environmental monitoring. Many of these setups have hundreds of cameras and tens of thousands of hours of video. The difficulty of analyzing such a massive volume of video data is apparent whenever there is an incident that requires foraging through vast video archives to identify events of interest. As a result, video summarization, that automatically extract a brief yet informative summary of these videos, has attracted intense attention in the recent years. Much progress has been made in developing a variety of ways to summarize a single video in form of a key sequence or video skim. However, generating a summary from a set of videos captured in a multi-camera network still remains as a novel and largely under-addressed problem. In this paper, with the aim of summarizing videos in a camera network, we introduce a novel representative selection approach via joint embedding and capped l21-norm minimization. The objective function is two-fold. The first is to capture the structural relationships of data points in a camera network via an embedding, which helps in characterizing the outliers and also in extracting a diverse set of representatives. The second is to use a capped l21-norm to model the sparsity and to suppress the influence of data outliers in representative selection. We propose to jointly optimize both of the objectives, such that embedding can not only characterize the structure, but also indicate the requirements of sparse representative selection. Extensive experiments on standard multi-camera datasets well demonstrate the efficacy of our method over state-of-the-art methods.
A mobile laboratory for surface and subsurface imaging in geo-hazard monitoring activity
NASA Astrophysics Data System (ADS)
Cornacchia, Carmela; Bavusi, Massimo; Loperte, Antonio; Pergola, Nicola; Pignatti, Stefano; Ponzo, Felice; Lapenna, Vincenzo
2010-05-01
A new research infrastructure for supporting ground-based remote sensing observations in the different phases of georisk management cycle is presented. This instrumental facility has been designed and realised by TeRN, a public-private consortium on Earth Observations and Natural Risks, in the frame of the project "ImpresAmbiente" funded by Italian Ministry of Research and University. The new infrastructure is equipped with ground-based sensors (hyperspectral cameras, thermal cameras, laser scanning and electromagnetic antennae) able to remotely map physical parameters and/or earth-surface properties (temperature, soil moisture, land cover, etc…) and to illuminate near-surface geological structures (fault, groundwater tables, landslide bodies etc...). Furthermore, the system can be used for non-invasive investigations of architectonic buildings and civil infrastructures (bridges, tunnel, road pavements, etc...) interested by natural and man-made hazards. The hyperspectral cameras can acquire high resolution images of earth-surface and cultural objects. They are operating in the Visible Near InfraRed (0.4÷1.0μm) with 1600 spatial pixel and 3.7nm of spectral sampling and in the Short Wave InfraRed (1.3÷2.5µm) spectral region with 320 spatial pixel and 5nm of spectral sampling. The IR cameras are operating in the Medium Wavelength InfraRed (3÷5µm; 640x512; NETD< 20 mK) and in the Very Long Wavelength InfraRed region (7.7÷11.5 µm; 320x256; NETD<25 mK) with a frame rate higher than 100Hz and are both equipped with a set of optical filters in order to operate in multi-spectral configuration. The technological innovation of ground-based laser scanning equipment has led to an increased resolution performances of surveys with applications in several field, as geology, architecture, environmental monitoring and cultural heritage. As a consequence, laser data can be useful integrated with traditional monitoring techniques. The Laser Scanner is characterized by very high data acquisition repetition rate up to 500.000 pxl/sec with a range resolution of 0.1 mm, vertical and horizontal FoV of 310° and 360° respectively with a resolution of 0.0018°. The system is also equipped with a metric camera allows to georeference the high resolution images acquired. The electromagnetic sensors allow to obtain in near real time high-resolution 2D and 3D subsurface tomographic images. The main components are a fully automatic resistivity meter for DC electrical surveys (resistivity) and Induced Polarization, a Ground Penetrating Radar with antennas covering range for 400 MHz to 1.5 GHz and a gradiometric magnetometric system. All the sensors can be installed on a mobile van and remotely controlled using wi-fi technologies. An all-time network connection capability is guaranteed by a self-configurable satellite link for data communication, which allows to transmit in near-real time experimental data coming from the field surveys and to share other geospatial information. This ICT facility is well suited for emergency response activities during and after catastrophic events. Sensor synergy, multi-temporal and multi-scale resolutions of surface and sub-surface imaging are the key technical features of this instrumental facility. Finally, in this work we shortly present some first preliminary results obtained during the emergence phase of Abruzzo earthquake (Central Italy).
A fast and automatic fusion algorithm for unregistered multi-exposure image sequence
NASA Astrophysics Data System (ADS)
Liu, Yan; Yu, Feihong
2014-09-01
Human visual system (HVS) can visualize all the brightness levels of the scene through visual adaptation. However, the dynamic range of most commercial digital cameras and display devices are smaller than the dynamic range of human eye. This implies low dynamic range (LDR) images captured by normal digital camera may lose image details. We propose an efficient approach to high dynamic (HDR) image fusion that copes with image displacement and image blur degradation in a computationally efficient manner, which is suitable for implementation on mobile devices. The various image registration algorithms proposed in the previous literatures are unable to meet the efficiency and performance requirements in the application of mobile devices. In this paper, we selected Oriented Brief (ORB) detector to extract local image structures. The descriptor selected in multi-exposure image fusion algorithm has to be fast and robust to illumination variations and geometric deformations. ORB descriptor is the best candidate in our algorithm. Further, we perform an improved RANdom Sample Consensus (RANSAC) algorithm to reject incorrect matches. For the fusion of images, a new approach based on Stationary Wavelet Transform (SWT) is used. The experimental results demonstrate that the proposed algorithm generates high quality images at low computational cost. Comparisons with a number of other feature matching methods show that our method gets better performance.
The sequence measurement system of the IR camera
NASA Astrophysics Data System (ADS)
Geng, Ai-hui; Han, Hong-xia; Zhang, Hai-bo
2011-08-01
Currently, the IR cameras are broadly used in the optic-electronic tracking, optic-electronic measuring, fire control and optic-electronic countermeasure field, but the output sequence of the most presently applied IR cameras in the project is complex and the giving sequence documents from the leave factory are not detailed. Aiming at the requirement that the continuous image transmission and image procession system need the detailed sequence of the IR cameras, the sequence measurement system of the IR camera is designed, and the detailed sequence measurement way of the applied IR camera is carried out. The FPGA programming combined with the SignalTap online observation way has been applied in the sequence measurement system, and the precise sequence of the IR camera's output signal has been achieved, the detailed document of the IR camera has been supplied to the continuous image transmission system, image processing system and etc. The sequence measurement system of the IR camera includes CameraLink input interface part, LVDS input interface part, FPGA part, CameraLink output interface part and etc, thereinto the FPGA part is the key composed part in the sequence measurement system. Both the video signal of the CmaeraLink style and the video signal of LVDS style can be accepted by the sequence measurement system, and because the image processing card and image memory card always use the CameraLink interface as its input interface style, the output signal style of the sequence measurement system has been designed into CameraLink interface. The sequence measurement system does the IR camera's sequence measurement work and meanwhile does the interface transmission work to some cameras. Inside the FPGA of the sequence measurement system, the sequence measurement program, the pixel clock modification, the SignalTap file configuration and the SignalTap online observation has been integrated to realize the precise measurement to the IR camera. Te sequence measurement program written by the verilog language combining the SignalTap tool on line observation can count the line numbers in one frame, pixel numbers in one line and meanwhile account the line offset and row offset of the image. Aiming at the complex sequence of the IR camera's output signal, the sequence measurement system of the IR camera accurately measures the sequence of the project applied camera, supplies the detailed sequence document to the continuous system such as image processing system and image transmission system and gives out the concrete parameters of the fval, lval, pixclk, line offset and row offset. The experiment shows that the sequence measurement system of the IR camera can get the precise sequence measurement result and works stably, laying foundation for the continuous system.
Application of Sensor Fusion to Improve Uav Image Classification
NASA Astrophysics Data System (ADS)
Jabari, S.; Fathollahi, F.; Zhang, Y.
2017-08-01
Image classification is one of the most important tasks of remote sensing projects including the ones that are based on using UAV images. Improving the quality of UAV images directly affects the classification results and can save a huge amount of time and effort in this area. In this study, we show that sensor fusion can improve image quality which results in increasing the accuracy of image classification. Here, we tested two sensor fusion configurations by using a Panchromatic (Pan) camera along with either a colour camera or a four-band multi-spectral (MS) camera. We use the Pan camera to benefit from its higher sensitivity and the colour or MS camera to benefit from its spectral properties. The resulting images are then compared to the ones acquired by a high resolution single Bayer-pattern colour camera (here referred to as HRC). We assessed the quality of the output images by performing image classification tests. The outputs prove that the proposed sensor fusion configurations can achieve higher accuracies compared to the images of the single Bayer-pattern colour camera. Therefore, incorporating a Pan camera on-board in the UAV missions and performing image fusion can help achieving higher quality images and accordingly higher accuracy classification results.
BLM Unmanned Aircraft Systems (UAS) Resource Management Operations
NASA Astrophysics Data System (ADS)
Hatfield, M. C.; Breen, A. L.; Thurau, R.
2016-12-01
The Department of the Interior Bureau of Land Management is funding research at the University of Alaska Fairbanks to study Unmanned Aircraft Systems (UAS) Resource Management Operations. In August 2015, the team conducted flight research at UAF's Toolik Field Station (TFS). The purpose was to determine the most efficient use of small UAS to collect low-altitude airborne digital stereo images, process the stereo imagery into close-range photogrammetry products, and integrate derived imagery products into the BLM's National Assessment, Inventory and Monitoring (AIM) Strategy. The AIM Strategy assists managers in answering questions of land resources at all organizational levels and develop management policy at regional and national levels. In Alaska, the BLM began to implement its AIM strategy in the National Petroleum Reserve-Alaska (NPR-A) in 2012. The primary goals of AIM-monitoring at the NPR-A are to implement an ecological baseline to monitor ecological trends, and to develop a monitoring network to understand the efficacy of management decisions. The long-term AIM strategy also complements other ongoing NPR-A monitoring processes, collects multi-use and multi-temporal data, and supports understanding of ecosystem management strategies in order to implement defensible natural resource management policy. The campaign measured vegetation types found in the NPR-A, using UAF's TFS location as a convenient proxy. The vehicle selected was the ACUASI Ptarmigan, a small hexacopter (based on DJI S800 airframe and 3DR autopilot) capable of carrying a 1.5 kg payload for 15 min for close-range environmental monitoring missions. The payload was a stereo camera system consisting of Sony NEX7's with various lens configurations (16/20/24/35 mm). A total of 77 flights were conducted over a 4 ½ day period, with 1.5 TB of data collected. Mission variables included camera height, UAS speed, transect overlaps, and camera lenses/settings. Invaluable knowledge was gained as to limitations and opportunities for field deployment of UAS relative to local conditions and vegetation type. Future efforts will focus of refining data analysis techniques and further optimizing UAS/sensor combinations and flight profiles.
Boxberger, Tobias; Fleming, Kevin; Pittore, Massimiliano; Parolai, Stefano; Pilz, Marco; Mikulla, Stefan
2017-10-20
The Multi-Parameter Wireless Sensing (MPwise) system is an innovative instrumental design that allows different sensor types to be combined with relatively high-performance computing and communications components. These units, which incorporate off-the-shelf components, can undertake complex information integration and processing tasks at the individual unit or node level (when used in a network), allowing the establishment of networks that are linked by advanced, robust and rapid communications routing and network topologies. The system (and its predecessors) was originally designed for earthquake risk mitigation, including earthquake early warning (EEW), rapid response actions, structural health monitoring, and site-effect characterization. For EEW, MPwise units are capable of on-site, decentralized, independent analysis of the recorded ground motion and based on this, may issue an appropriate warning, either by the unit itself or transmitted throughout a network by dedicated alarming procedures. The multi-sensor capabilities of the system allow it to be instrumented with standard strong- and weak-motion sensors, broadband sensors, MEMS (namely accelerometers), cameras, temperature and humidity sensors, and GNSS receivers. In this work, the MPwise hardware, software and communications schema are described, as well as an overview of its possible applications. While focusing on earthquake risk mitigation actions, the aim in the future is to expand its capabilities towards a more multi-hazard and risk mitigation role. Overall, MPwise offers considerable flexibility and has great potential in contributing to natural hazard risk mitigation.
Boxberger, Tobias; Fleming, Kevin; Pittore, Massimiliano; Parolai, Stefano; Pilz, Marco; Mikulla, Stefan
2017-01-01
The Multi-Parameter Wireless Sensing (MPwise) system is an innovative instrumental design that allows different sensor types to be combined with relatively high-performance computing and communications components. These units, which incorporate off-the-shelf components, can undertake complex information integration and processing tasks at the individual unit or node level (when used in a network), allowing the establishment of networks that are linked by advanced, robust and rapid communications routing and network topologies. The system (and its predecessors) was originally designed for earthquake risk mitigation, including earthquake early warning (EEW), rapid response actions, structural health monitoring, and site-effect characterization. For EEW, MPwise units are capable of on-site, decentralized, independent analysis of the recorded ground motion and based on this, may issue an appropriate warning, either by the unit itself or transmitted throughout a network by dedicated alarming procedures. The multi-sensor capabilities of the system allow it to be instrumented with standard strong- and weak-motion sensors, broadband sensors, MEMS (namely accelerometers), cameras, temperature and humidity sensors, and GNSS receivers. In this work, the MPwise hardware, software and communications schema are described, as well as an overview of its possible applications. While focusing on earthquake risk mitigation actions, the aim in the future is to expand its capabilities towards a more multi-hazard and risk mitigation role. Overall, MPwise offers considerable flexibility and has great potential in contributing to natural hazard risk mitigation. PMID:29053608
Multi-sensor fusion over the World Trade Center disaster site
NASA Astrophysics Data System (ADS)
Rodarmel, Craig; Scott, Lawrence; Simerlink, Deborah A.; Walker, Jeffrey
2002-09-01
The immense size and scope of the rescue and clean-up of the World Trade Center site created a need for data that would provide a total overview of the disaster area. To fulfill this need, the New York State Office for Technology (NYSOFT) contracted with EarthData International to collect airborne remote sensing data over Ground Zero with an airborne light detection and ranging (LIDAR) sensor, a high-resolution digital camera, and a thermal camera. The LIDAR data provided a three-dimensional elevation model of the ground surface that was used for volumetric calculations and also in the orthorectification of the digital images. The digital camera provided high-resolution imagery over the site to aide the rescuers in placement of equipment and other assets. In addition, the digital imagery was used to georeference the thermal imagery and also provided the visual background for the thermal data. The thermal camera aided in the location and tracking of underground fires. The combination of data from these three sensors provided the emergency crews with a timely, accurate overview containing a wealth of information of the rapidly changing disaster site. Because of the dynamic nature of the site, the data was acquired on a daily basis, processed, and turned over to NYSOFT within twelve hours of the collection. During processing, the three datasets were combined and georeferenced to allow them to be inserted into the client's geographic information systems.
2002-03-05
Astronaut James H. Newman, mission specialist, floats about in the Space Shuttle Columbia's cargo bay while working in tandem with astronaut Michael J. Massimino (out of frame),mission specialist, during the STS-109 mission's second day of extravehicular activity (EVA). Inside Columbia's cabin, astronaut Nancy J. Currie, mission specialist, controlled the Remote Manipulator System (RMS) to assist the two in their work on the Hubble Space Telescope (HST). The RMS was used to capture the telescope and secure it into Columbia's cargo bay.Part of the giant telescope's base, latched down in the payload bay, can be seen behind Newman. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the HST. The Marshall Space Flight Center in Huntsville, Alabama had responsibility for the design, development, and contruction of the HST, which is the most powerful and sophisticated telescope ever built. STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.
Low SWaP multispectral sensors using dichroic filter arrays
NASA Astrophysics Data System (ADS)
Dougherty, John; Varghese, Ron
2015-06-01
The benefits of multispectral imaging are well established in a variety of applications including remote sensing, authentication, satellite and aerial surveillance, machine vision, biomedical, and other scientific and industrial uses. However, many of the potential solutions require more compact, robust, and cost-effective cameras to realize these benefits. The next generation of multispectral sensors and cameras needs to deliver improvements in size, weight, power, portability, and spectral band customization to support widespread deployment for a variety of purpose-built aerial, unmanned, and scientific applications. A novel implementation uses micro-patterning of dichroic filters1 into Bayer and custom mosaics, enabling true real-time multispectral imaging with simultaneous multi-band image acquisition. Consistent with color image processing, individual spectral channels are de-mosaiced with each channel providing an image of the field of view. This approach can be implemented across a variety of wavelength ranges and on a variety of detector types including linear, area, silicon, and InGaAs. This dichroic filter array approach can also reduce payloads and increase range for unmanned systems, with the capability to support both handheld and autonomous systems. Recent examples and results of 4 band RGB + NIR dichroic filter arrays in multispectral cameras are discussed. Benefits and tradeoffs of multispectral sensors using dichroic filter arrays are compared with alternative approaches - including their passivity, spectral range, customization options, and scalable production.
NASA Astrophysics Data System (ADS)
Darker, Iain T.; Kuo, Paul; Yang, Ming Yuan; Blechko, Anastassia; Grecos, Christos; Makris, Dimitrios; Nebel, Jean-Christophe; Gale, Alastair G.
2009-05-01
Findings from the current UK national research programme, MEDUSA (Multi Environment Deployable Universal Software Application), are presented. MEDUSA brings together two approaches to facilitate the design of an automatic, CCTV-based firearm detection system: psychological-to elicit strategies used by CCTV operators; and machine vision-to identify key cues derived from camera imagery. Potentially effective human- and machine-based strategies have been identified; these will form elements of the final system. The efficacies of these algorithms have been tested on staged CCTV footage in discriminating between firearms and matched distractor objects. Early results indicate the potential for this combined approach.
3D Perception Technologies for Surgical Operating Theatres.
Beyl, T; Schreiter, L; Nicolai, P; Raczkowsky, J; Wörn, H
2016-01-01
3D Perception technologies have been explored in various fields. This paper explores the application of such technologies for surgical operating theatres. Clinical applications can be found in workflow detection, tracking and analysis, collision avoidance with medical robots, perception of interaction between participants of the operation, training of the operation room crew, patient calibration and many more. In this paper a complete perception solution for the operating room is shown. The system is based on the ToF technology integrated to the Microsoft Kinect One implements a multi camera approach. Special emphasize is put on the tracking of the personnel and the evaluation of the system performance and accuracy.
Multi-Parameter Wireless Monitoring and Telecommand of a Rocket Payload: Design and Implementation
NASA Astrophysics Data System (ADS)
Pamungkas, Arga C.; Putra, Alma A.; Puspitaningayu, Pradini; Fransisca, Yulia; Widodo, Arif
2018-04-01
A rocket system generally consists of two parts, the rocket motor and the payload. The payload system is built of several sensors such as accelerometer, gyroscope, magnetometer, and also a surveillance camera. These sensors are used to monitor the rocket in a three-dimensional axis which determine its attitude. Additionally, the payload must be able to perform image capturing in a certain distance using telecommand. This article is intended to describe the design and also the implementation of a rocket payload which has attitude monitoring and telecommand ability from the ground control station using a long-range wireless module Digi XBee Pro 900 HP.
3D Modeling from Multi-views Images for Cultural Heritage in Wat-Pho, Thailand
NASA Astrophysics Data System (ADS)
Soontranon, N.; Srestasathiern, P.; Lawawirojwong, S.
2015-08-01
In Thailand, there are several types of (tangible) cultural heritages. This work focuses on 3D modeling of the heritage objects from multi-views images. The images are acquired by using a DSLR camera which costs around 1,500 (camera and lens). Comparing with a 3D laser scanner, the camera is cheaper and lighter than the 3D scanner. Hence, the camera is available for public users and convenient for accessing narrow areas. The acquired images consist of various sculptures and architectures in Wat-Pho which is a Buddhist temple located behind the Grand Palace (Bangkok, Thailand). Wat-Pho is known as temple of the reclining Buddha and the birthplace of traditional Thai massage. To compute the 3D models, a diagram is separated into following steps; Data acquisition, Image matching, Image calibration and orientation, Dense matching and Point cloud processing. For the initial work, small heritages less than 3 meters height are considered for the experimental results. A set of multi-views images of an interested object is used as input data for 3D modeling. In our experiments, 3D models are obtained from MICMAC (open source) software developed by IGN, France. The output of 3D models will be represented by using standard formats of 3D point clouds and triangulated surfaces such as .ply, .off, .obj, etc. To compute for the efficient 3D models, post-processing techniques are required for the final results e.g. noise reduction, surface simplification and reconstruction. The reconstructed 3D models can be provided for public access such as website, DVD, printed materials. The high accurate 3D models can also be used as reference data of the heritage objects that must be restored due to deterioration of a lifetime, natural disasters, etc.
Integrated multisensor perimeter detection systems
NASA Astrophysics Data System (ADS)
Kent, P. J.; Fretwell, P.; Barrett, D. J.; Faulkner, D. A.
2007-10-01
The report describes the results of a multi-year programme of research aimed at the development of an integrated multi-sensor perimeter detection system capable of being deployed at an operational site. The research was driven by end user requirements in protective security, particularly in threat detection and assessment, where effective capability was either not available or prohibitively expensive. Novel video analytics have been designed to provide robust detection of pedestrians in clutter while new radar detection and tracking algorithms provide wide area day/night surveillance. A modular integrated architecture based on commercially available components has been developed. A graphical user interface allows intuitive interaction and visualisation with the sensors. The fusion of video, radar and other sensor data provides the basis of a threat detection capability for real life conditions. The system was designed to be modular and extendable in order to accommodate future and legacy surveillance sensors. The current sensor mix includes stereoscopic video cameras, mmWave ground movement radar, CCTV and a commercially available perimeter detection cable. The paper outlines the development of the system and describes the lessons learnt after deployment in a pilot trial.
Airborne multicamera system for geo-spatial applications
NASA Astrophysics Data System (ADS)
Bachnak, Rafic; Kulkarni, Rahul R.; Lyle, Stacey; Steidley, Carl W.
2003-08-01
Airborne remote sensing has many applications that include vegetation detection, oceanography, marine biology, geographical information systems, and environmental coastal science analysis. Remotely sensed images, for example, can be used to study the aftermath of episodic events such as the hurricanes and floods that occur year round in the coastal bend area of Corpus Christi. This paper describes an Airborne Multi-Spectral Imaging System that uses digital cameras to provide high resolution at very high rates. The software is based on Delphi 5.0 and IC Imaging Control's ActiveX controls. Both time and the GPS coordinates are recorded. Three successful test flights have been conducted so far. The paper present flight test results and discusses the issues being addressed to fully develop the system.
A multi-sensor scenario for coastal surveillance
NASA Astrophysics Data System (ADS)
van den Broek, A. C.; van den Broek, S. P.; van den Heuvel, J. C.; Schwering, P. B. W.; van Heijningen, A. W. P.
2007-10-01
Maritime borders and coastal zones are susceptible to threats such as drug trafficking, piracy, undermining economical activities. At TNO Defence, Security and Safety various studies aim at improving situational awareness in a coastal zone. In this study we focus on multi-sensor surveillance of the coastal environment. We present a study on improving classification results for small sea surface targets using an advanced sensor suite and a scenario in which a small boat is approaching the coast. A next generation sensor suite mounted on a tower has been defined consisting of a maritime surveillance and tracking radar system, capable of producing range profiles and ISAR imagery of ships, an advanced infrared camera and a laser range profiler. For this suite we have developed a multi-sensor classification procedure, which is used to evaluate the capabilities for recognizing and identifying non-cooperative ships in coastal waters. We have found that the different sensors give complementary information. Each sensor has its own specific distance range in which it contributes most. A multi-sensor approach reduces the number of misclassifications and reliable classification results are obtained earlier compared to a single sensor approach.
NASA Astrophysics Data System (ADS)
Turner, D.; Lucieer, A.; McCabe, M.; Parkes, S.; Clarke, I.
2017-08-01
In this study, we assess two push broom hyperspectral sensors as carried by small (10-15 kg) multi-rotor Unmanned Aircraft Systems (UAS). We used a Headwall Photonics micro-Hyperspec push broom sensor with 324 spectral bands (4-5 nm FWHM) and a Headwall Photonics nano-Hyperspec sensor with 270 spectral bands (6 nm FWHM) both in the VNIR spectral range (400-1000 nm). A gimbal was used to stabilise the sensors in relation to the aircraft flight dynamics, and for the micro-Hyperspec a tightly coupled dual frequency Global Navigation Satellite System (GNSS) receiver, an Inertial Measurement Unit (IMU), and Machine Vision Camera (MVC) were used for attitude and position determination. For the nano-Hyperspec, a navigation grade GNSS system and IMU provided position and attitude data. This study presents the geometric results of one flight over a grass oval on which a dense Ground Control Point (GCP) network was deployed. The aim being to ascertain the geometric accuracy achievable with the system. Using the PARGE software package (ReSe - Remote Sensing Applications) we ortho-rectify the push broom hyperspectral image strips and then quantify the accuracy of the ortho-rectification by using the GCPs as check points. The orientation (roll, pitch, and yaw) of the sensor is measured by the IMU. Alternatively imagery from a MVC running at 15 Hz, with accurate camera position data can be processed with Structure from Motion (SfM) software to obtain an estimated camera orientation. In this study, we look at which of these data sources will yield a flight strip with the highest geometric accuracy.
Low-cost far infrared bolometer camera for automotive use
NASA Astrophysics Data System (ADS)
Vieider, Christian; Wissmar, Stanley; Ericsson, Per; Halldin, Urban; Niklaus, Frank; Stemme, Göran; Källhammer, Jan-Erik; Pettersson, Håkan; Eriksson, Dick; Jakobsen, Henrik; Kvisterøy, Terje; Franks, John; VanNylen, Jan; Vercammen, Hans; VanHulsel, Annick
2007-04-01
A new low-cost long-wavelength infrared bolometer camera system is under development. It is designed for use with an automatic vision algorithm system as a sensor to detect vulnerable road users in traffic. Looking 15 m in front of the vehicle it can in case of an unavoidable impact activate a brake assist system or other deployable protection system. To achieve our cost target below €100 for the sensor system we evaluate the required performance and can reduce the sensitivity to 150 mK and pixel resolution to 80 x 30. We address all the main cost drivers as sensor size and production yield along with vacuum packaging, optical components and large volume manufacturing technologies. The detector array is based on a new type of high performance thermistor material. Very thin Si/SiGe single crystal multi-layers are grown epitaxially. Due to the resulting valence barriers a high temperature coefficient of resistance is achieved (3.3%/K). Simultaneously, the high quality crystalline material provides very low 1/f-noise characteristics and uniform material properties. The thermistor material is transferred from the original substrate wafer to the read-out circuit using adhesive wafer bonding and subsequent thinning. Bolometer arrays can then be fabricated using industry standard MEMS process and materials. The inherently good detector performance allows us to reduce the vacuum requirement and we can implement wafer level vacuum packaging technology used in established automotive sensor fabrication. The optical design is reduced to a single lens camera. We develop a low cost molding process using a novel chalcogenide glass (GASIR®3) and integrate anti-reflective and anti-erosion properties using diamond like carbon coating.
2002-03-05
STS-109 Astronauts Michael J. Massimino and James H. Newman were making their second extravehicular activity (EVA) of their mission when astronaut Massimino, mission specialist, peered into Columbia's crew cabin during a brief break from work on the Hubble Space Telescope (HST). The HST is latched down just a few feet behind him in Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.
STS-109 Astronaut Michael J. Massimino Peers Into Window of Shuttle During EVA
NASA Technical Reports Server (NTRS)
2002-01-01
STS-109 Astronauts Michael J. Massimino and James H. Newman were making their second extravehicular activity (EVA) of their mission when astronaut Massimino, mission specialist, peered into Columbia's crew cabin during a brief break from work on the Hubble Space Telescope (HST). The HST is latched down just a few feet behind him in Columbia's cargo bay. The Space Shuttle Columbia STS-109 mission lifted off March 1, 2002 with goals of repairing and upgrading the Hubble Space Telescope (HST). STS-109 upgrades to the HST included: replacement of the solar array panels; replacement of the power control unit (PCU); replacement of the Faint Object Camera (FOC) with a new advanced camera for Surveys (ACS); and installation of the experimental cooling system for the Hubble's Near-Infrared Camera and Multi-object Spectrometer (NICMOS), which had been dormant since January 1999 when its original coolant ran out. The Marshall Space Flight Center in Huntsville, Alabama had the responsibility for the design, development, and construction of the HST, which is the most powerful and sophisticated telescope ever built. Lasting 10 days, 22 hours, and 11 minutes, the STS-109 mission was the 108th flight overall in NASA's Space Shuttle Program.
NASA Astrophysics Data System (ADS)
de Villiers, Jason P.; Bachoo, Asheer K.; Nicolls, Fred C.; le Roux, Francois P. J.
2011-05-01
Tracking targets in a panoramic image is in many senses the inverse problem of tracking targets with a narrow field of view camera on a pan-tilt pedestal. In a narrow field of view camera tracking a moving target, the object is constant and the background is changing. A panoramic camera is able to model the entire scene, or background, and those areas it cannot model well are the potential targets and typically subtended far fewer pixels in the panoramic view compared to the narrow field of view. The outputs of an outward staring array of calibrated machine vision cameras are stitched into a single omnidirectional panorama and used to observe False Bay near Simon's Town, South Africa. A ground truth data-set was created by geo-aligning the camera array and placing a differential global position system receiver on a small target boat thus allowing its position in the array's field of view to be determined. Common tracking techniques including level-sets, Kalman filters and particle filters were implemented to run on the central processing unit of the tracking computer. Image enhancement techniques including multi-scale tone mapping, interpolated local histogram equalisation and several sharpening techniques were implemented on the graphics processing unit. An objective measurement of each tracking algorithm's robustness in the presence of sea-glint, low contrast visibility and sea clutter - such as white caps is performed on the raw recorded video data. These results are then compared to those obtained with the enhanced video data.
An Insect Eye Inspired Miniaturized Multi-Camera System for Endoscopic Imaging.
Cogal, Omer; Leblebici, Yusuf
2017-02-01
In this work, we present a miniaturized high definition vision system inspired by insect eyes, with a distributed illumination method, which can work in dark environments for proximity imaging applications such as endoscopy. Our approach is based on modeling biological systems with off-the-shelf miniaturized cameras combined with digital circuit design for real time image processing. We built a 5 mm radius hemispherical compound eye, imaging a 180 ° ×180 ° degrees field of view while providing more than 1.1 megapixels (emulated ommatidias) as real-time video with an inter-ommatidial angle ∆ϕ = 0.5 ° at 18 mm radial distance. We made an FPGA implementation of the image processing system which is capable of generating 25 fps video with 1080 × 1080 pixel resolution at a 120 MHz processing clock frequency. When compared to similar size insect eye mimicking systems in literature, the system proposed in this paper features 1000 × resolution increase. To the best of our knowledge, this is the first time that a compound eye with built-in illumination idea is reported. We are offering our miniaturized imaging system for endoscopic applications like colonoscopy or laparoscopic surgery where there is a need for large field of view high definition imagery. For that purpose we tested our system inside a human colon model. We also present the resulting images and videos from the human colon model in this paper.
RESOURCESAT-2: a mission for Earth resources management
NASA Astrophysics Data System (ADS)
Venkata Rao, M.; Gupta, J. P.; Rattan, Ram; Thyagarajan, K.
2006-12-01
The Indian Space Research Organisation (ISRO) has established an operational Remote sensing satellite system by launching its first satellite, IRS-1A in 1988, followed by a series of IRS spacecraft. The IRS-1C/1D satellites with their unique combination of Payloads have taken a lead position in the Global remote sensing scenario. Realising the growing User demands for the "Multi" level approach in terms of Spatial, Spectral, Temporal and Radiometric resolutions, ISRO identified the Resourcesat as a continuity as well as improved RS Satellite. The Resourcesat-1 (IRS-P6) was launched in October 2003 using PSLV launch vehicle and it is in operational service. Resourcesat-2 is its follow-on Mission scheduled for launch in 2008. Each Resourcesat satellite carries three Electro-optical cameras as its payload - LISS-3, LISS-4 and AWIFS. All the three are multi-spectral push-broom scanners with linear array CCDs as Detectors. LISS-3 and AWIFS operate in four identical spectral bands in the VIS-NIR-SWIR range while LISS-4 is a high resolution camera with three spectral bands in VIS-NIR range. In order to meet the stringent requirements of band-to-band registration and platform stability, several improvements have been incorporated in the mainframe Bus configuration like wide field Star trackers, precision Gyroscopes, on-board GPS receiver etc,. The Resourcesat data finds its application in several areas like agricultural crop discrimination and monitoring, crop acreage/yield estimation, precision farming, water resources, forest mapping, Rural infrastructure development, disaster management etc,. to name a few. A brief description of the Payload cameras, spacecraft bus elements and operational modes and few applications are presented.
1991-04-03
The USML-1 Glovebox (GBX) is a multi-user facility supporting 16 experiments in fluid dynamics, combustion sciences, crystal growth, and technology demonstration. The GBX has an enclosed working space which minimizes the contamination risks to both Spacelab and experiment samples. The GBX supports four charge-coupled device (CCD) cameras (two of which may be operated simultaneously) with three black-and-white and three color camera CCD heads available. The GBX also has a backlight panel, a 35 mm camera, and a stereomicroscope that offers high-magnification viewing of experiment samples. Video data can also be downlinked in real-time. The GBX also provides electrical power for experiment hardware, a time-temperature display, and cleaning supplies.
1995-08-29
The USML-1 Glovebox (GBX) is a multi-user facility supporting 16 experiments in fluid dynamics, combustion sciences, crystal growth, and technology demonstration. The GBX has an enclosed working space which minimizes the contamination risks to both Spacelab and experiment samples. The GBX supports four charge-coupled device (CCD) cameras (two of which may be operated simultaneously) with three black-and-white and three color camera CCD heads available. The GBX also has a backlight panel, a 35 mm camera, and a stereomicroscope that offers high-magnification viewing of experiment samples. Video data can also be downlinked in real-time. The GBX also provides electrical power for experiment hardware, a time-temperature display, and cleaning supplies.
A Coded Structured Light System Based on Primary Color Stripe Projection and Monochrome Imaging
Barone, Sandro; Paoli, Alessandro; Razionale, Armando Viviano
2013-01-01
Coded Structured Light techniques represent one of the most attractive research areas within the field of optical metrology. The coding procedures are typically based on projecting either a single pattern or a temporal sequence of patterns to provide 3D surface data. In this context, multi-slit or stripe colored patterns may be used with the aim of reducing the number of projected images. However, color imaging sensors require the use of calibration procedures to address crosstalk effects between different channels and to reduce the chromatic aberrations. In this paper, a Coded Structured Light system has been developed by integrating a color stripe projector and a monochrome camera. A discrete coding method, which combines spatial and temporal information, is generated by sequentially projecting and acquiring a small set of fringe patterns. The method allows the concurrent measurement of geometrical and chromatic data by exploiting the benefits of using a monochrome camera. The proposed methodology has been validated by measuring nominal primitive geometries and free-form shapes. The experimental results have been compared with those obtained by using a time-multiplexing gray code strategy. PMID:24129018
A coded structured light system based on primary color stripe projection and monochrome imaging.
Barone, Sandro; Paoli, Alessandro; Razionale, Armando Viviano
2013-10-14
Coded Structured Light techniques represent one of the most attractive research areas within the field of optical metrology. The coding procedures are typically based on projecting either a single pattern or a temporal sequence of patterns to provide 3D surface data. In this context, multi-slit or stripe colored patterns may be used with the aim of reducing the number of projected images. However, color imaging sensors require the use of calibration procedures to address crosstalk effects between different channels and to reduce the chromatic aberrations. In this paper, a Coded Structured Light system has been developed by integrating a color stripe projector and a monochrome camera. A discrete coding method, which combines spatial and temporal information, is generated by sequentially projecting and acquiring a small set of fringe patterns. The method allows the concurrent measurement of geometrical and chromatic data by exploiting the benefits of using a monochrome camera. The proposed methodology has been validated by measuring nominal primitive geometries and free-form shapes. The experimental results have been compared with those obtained by using a time-multiplexing gray code strategy.
Focal Plane Detectors for the Advanced Gamma-Ray Imaging System (AGIS)
NASA Astrophysics Data System (ADS)
Otte, A. N.; Byrum, K.; Drake, G.; Falcone, A.; Funk, S.; Horan, D.; Mukherjee, R.; Smith, A.; Tajima, H.; Wagner, R. G.; Williams, D. A.
2008-12-01
The Advanced Gamma-Ray Imaging System (AGIS) is a concept for the next generation observatory in ground-based very high energy gamma-ray astronomy. Design goals are ten times better sensitivity, higher angular resolution, and a lower energy threshold than existing Cherenkov telescopes. Simulations show that a substantial improvement in angular resolution may be achieved if the pixel diameter is reduced to the order of 0.05 deg, i.e. two to three times smaller than the pixel diameter of current Cherenkov telescope cameras. At these dimensions, photon detectors with smaller physical dimensions can be attractive alternatives to the classical photomultiplier tube (PMT). Furthermore, the operation of an experiment with the size of AGIS requires photon detectors that are among other things more reliable, more durable, and possibly higher efficiency photon detectors. Alternative photon detectors we are considering for AGIS include both silicon photomultipliers (SiPMs) and multi-anode photomultipliers (MAPMTs). Here we present results from laboratory testing of MAPMTs and SiPMs along with results from the first incorporation of these devices into cameras on test bed Cherenkov telescopes.
Winter sky brightness and cloud cover at Dome A, Antarctica
NASA Astrophysics Data System (ADS)
Moore, Anna M.; Yang, Yi; Fu, Jianning; Ashley, Michael C. B.; Cui, Xiangqun; Feng, Long Long; Gong, Xuefei; Hu, Zhongwen; Lawrence, Jon S.; Luong-Van, Daniel M.; Riddle, Reed; Shang, Zhaohui; Sims, Geoff; Storey, John W. V.; Tothill, Nicholas F. H.; Travouillon, Tony; Wang, Lifan; Yang, Huigen; Yang, Ji; Zhou, Xu; Zhu, Zhenxi
2013-01-01
At the summit of the Antarctic plateau, Dome A offers an intriguing location for future large scale optical astronomical observatories. The Gattini Dome A project was created to measure the optical sky brightness and large area cloud cover of the winter-time sky above this high altitude Antarctic site. The wide field camera and multi-filter system was installed on the PLATO instrument module as part of the Chinese-led traverse to Dome A in January 2008. This automated wide field camera consists of an Apogee U4000 interline CCD coupled to a Nikon fisheye lens enclosed in a heated container with glass window. The system contains a filter mechanism providing a suite of standard astronomical photometric filters (Bessell B, V, R) and a long-pass red filter for the detection and monitoring of airglow emission. The system operated continuously throughout the 2009, and 2011 winter seasons and part-way through the 2010 season, recording long exposure images sequentially for each filter. We have in hand one complete winter-time dataset (2009) returned via a manned traverse. We present here the first measurements of sky brightness in the photometric V band, cloud cover statistics measured so far and an estimate of the extinction.
Detection of non-classical space-time correlations with a novel type of single-photon camera.
Just, Felix; Filipenko, Mykhaylo; Cavanna, Andrea; Michel, Thilo; Gleixner, Thomas; Taheri, Michael; Vallerga, John; Campbell, Michael; Tick, Timo; Anton, Gisela; Chekhova, Maria V; Leuchs, Gerd
2014-07-14
During the last decades, multi-pixel detectors have been developed capable of registering single photons. The newly developed hybrid photon detector camera has a remarkable property that it has not only spatial but also temporal resolution. In this work, we apply this device to the detection of non-classical light from spontaneous parametric down-conversion and use two-photon correlations for the absolute calibration of its quantum efficiency.
NASA Astrophysics Data System (ADS)
Gliss, Christine; Parel, Jean-Marie A.; Flynn, John T.; Pratisto, Hans S.; Niederer, Peter F.
2003-07-01
We present a miniaturized version of a fundus camera. The camera is designed for the use in screening for retinopathy of prematurity (ROP). There, but also in other applications a small, light weight, digital camera system can be extremely useful. We present a small wide angle digital camera system. The handpiece is significantly smaller and lighter then in all other systems. The electronics is truly portable fitting in a standard boardcase. The camera is designed to be offered at a compatible price. Data from tests on young rabbits' eyes is presented. The development of the camera system is part of a telemedicine project screening for ROP. Telemedical applications are a perfect application for this camera system using both advantages: the portability as well as the digital image.
Multi-Angle View of the Canary Islands
NASA Technical Reports Server (NTRS)
2000-01-01
A multi-angle view of the Canary Islands in a dust storm, 29 February 2000. At left is a true-color image taken by the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra satellite. This image was captured by the MISR camera looking at a 70.5-degree angle to the surface, ahead of the spacecraft. The middle image was taken by the MISR downward-looking (nadir) camera, and the right image is from the aftward 70.5-degree camera. The images are reproduced using the same radiometric scale, so variations in brightness, color, and contrast represent true variations in surface and atmospheric reflectance with angle. Windblown dust from the Sahara Desert is apparent in all three images, and is much brighter in the oblique views. This illustrates how MISR's oblique imaging capability makes the instrument a sensitive detector of dust and other particles in the atmosphere. Data for all channels are presented in a Space Oblique Mercator map projection to facilitate their co-registration. The images are about 400 km (250 miles)wide, with a spatial resolution of about 1.1 kilometers (1,200 yards). North is toward the top. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra satellite is managed by NASA's Goddard Space Flight Center, Greenbelt, MD. JPL is a division of the California Institute of Technology.
Frequency division multiplexed multi-color fluorescence microscope system
NASA Astrophysics Data System (ADS)
Le, Vu Nam; Yang, Huai Dong; Zhang, Si Chun; Zhang, Xin Rong; Jin, Guo Fan
2017-10-01
Grayscale camera can only obtain gray scale image of object, while the multicolor imaging technology can obtain the color information to distinguish the sample structures which have the same shapes but in different colors. In fluorescence microscopy, the current method of multicolor imaging are flawed. Problem of these method is affecting the efficiency of fluorescence imaging, reducing the sampling rate of CCD etc. In this paper, we propose a novel multiple color fluorescence microscopy imaging method which based on the Frequency division multiplexing (FDM) technology, by modulating the excitation lights and demodulating the fluorescence signal in frequency domain. This method uses periodic functions with different frequency to modulate amplitude of each excitation lights, and then combine these beams for illumination in a fluorescence microscopy imaging system. The imaging system will detect a multicolor fluorescence image by a grayscale camera. During the data processing, the signal obtained by each pixel of the camera will be processed with discrete Fourier transform, decomposed by color in the frequency domain and then used inverse discrete Fourier transform. After using this process for signals from all of the pixels, monochrome images of each color on the image plane can be obtained and multicolor image is also acquired. Based on this method, this paper has constructed and set up a two-color fluorescence microscope system with two excitation wavelengths of 488 nm and 639 nm. By using this system to observe the linearly movement of two kinds of fluorescent microspheres, after the data processing, we obtain a two-color fluorescence dynamic video which is consistent with the original image. This experiment shows that the dynamic phenomenon of multicolor fluorescent biological samples can be generally observed by this method. Compared with the current methods, this method can obtain the image signals of each color at the same time, and the color video's frame rate is consistent with the frame rate of the camera. The optical system is simpler and does not need extra color separation element. In addition, this method has a good filtering effect on the ambient light or other light signals which are not affected by the modulation process.
Camera systems in human motion analysis for biomedical applications
NASA Astrophysics Data System (ADS)
Chin, Lim Chee; Basah, Shafriza Nisha; Yaacob, Sazali; Juan, Yeap Ewe; Kadir, Aida Khairunnisaa Ab.
2015-05-01
Human Motion Analysis (HMA) system has been one of the major interests among researchers in the field of computer vision, artificial intelligence and biomedical engineering and sciences. This is due to its wide and promising biomedical applications, namely, bio-instrumentation for human computer interfacing and surveillance system for monitoring human behaviour as well as analysis of biomedical signal and image processing for diagnosis and rehabilitation applications. This paper provides an extensive review of the camera system of HMA, its taxonomy, including camera types, camera calibration and camera configuration. The review focused on evaluating the camera system consideration of the HMA system specifically for biomedical applications. This review is important as it provides guidelines and recommendation for researchers and practitioners in selecting a camera system of the HMA system for biomedical applications.
3D measurement by digital photogrammetry
NASA Astrophysics Data System (ADS)
Schneider, Carl T.
1993-12-01
Photogrammetry is well known in geodetic surveys as aerial photogrammetry or close range applications as architectural photogrammetry. The photogrammetric methods and algorithms combined with digital cameras and digital image processing methods are now introduced for industrial applications as automation and quality control. The presented paper will describe the photogrammetric and digital image processing algorithms and the calibration methods. These algorithms and methods were demonstrated with application examples. These applications are a digital photogrammetric workstation as a mobil multi purpose 3D measuring tool and a tube measuring system as an example for a single purpose tool.
Multispectral Snapshot Imagers Onboard Small Satellite Formations for Multi-Angular Remote Sensing
NASA Technical Reports Server (NTRS)
Nag, Sreeja; Hewagama, Tilak; Georgiev, Georgi; Pasquale, Bert; Aslam, Shahid; Gatebe, Charles K.
2017-01-01
Multispectral snapshot imagers are capable of producing 2D spatial images with a single exposure at selected, numerous wavelengths using the same camera, therefore operate differently from push broom or whiskbroom imagers. They are payloads of choice in multi-angular, multi-spectral imaging missions that use small satellites flying in controlled formation, to retrieve Earth science measurements dependent on the targets Bidirectional Reflectance-Distribution Function (BRDF). Narrow fields of view are needed to capture images with moderate spatial resolution. This paper quantifies the dependencies of the imagers optical system, spectral elements and camera on the requirements of the formation mission and their impact on performance metrics such as spectral range, swath and signal to noise ratio (SNR). All variables and metrics have been generated from a comprehensive, payload design tool. The baseline optical parameters selected (diameter 7 cm, focal length 10.5 cm, pixel size 20 micron, field of view 1.15 deg) and snapshot imaging technologies are available. The spectral components shortlisted were waveguide spectrometers, acousto-optic tunable filters (AOTF), electronically actuated Fabry-Perot interferometers, and integral field spectrographs. Qualitative evaluation favored AOTFs because of their low weight, small size, and flight heritage. Quantitative analysis showed that waveguide spectrometers perform better in terms of achievable swath (10-90 km) and SNR (greater than 20) for 86 wavebands, but the data volume generated will need very high bandwidth communication to downlink. AOTFs meet the external data volume caps well as the minimum spectral (wavebands) and radiometric (SNR) requirements, therefore are found to be currently feasible in spite of lower swath and SNR.
NASA Technical Reports Server (NTRS)
2012-01-01
The topics include: 1) Spectral Profiler Probe for In Situ Snow Grain Size and Composition Stratigraphy; 2) Portable Fourier Transform Spectroscopy for Analysis of Surface Contamination and Quality Control; 3) In Situ Geochemical Analysis and Age Dating of Rocks Using Laser Ablation-Miniature Mass Spectrometer; 4) Physics Mining of Multi-Source Data Sets; 5) Photogrammetry Tool for Forensic Analysis; 6) Connect Global Positioning System RF Module; 7) Simple Cell Balance Circuit; 8) Miniature EVA Software Defined Radio; 9) Remotely Accessible Testbed for Software Defined Radio Development; 10) System-of-Systems Technology-Portfolio-Analysis Tool; 11) VESGEN Software for Mapping and Quantification of Vascular Regulators; 12) Constructing a Database From Multiple 2D Images for Camera Pose Estimation and Robot Localization; 13) Adaption of G-TAG Software for Validating Touch and Go Asteroid Sample Return Design Methodology; 14) 3D Visualization for Phoenix Mars Lander Science Operations; 15) RxGen General Optical Model Prescription Generator; 16) Carbon Nanotube Bonding Strength Enhancement Using Metal Wicking Process; 17) Multi-Layer Far-Infrared Component Technology; 18) Germanium Lift-Off Masks for Thin Metal Film Patterning; 19) Sealing Materials for Use in Vacuum at High Temperatures; 20) Radiation Shielding System Using a Composite of Carbon Nanotubes Loaded With Electropolymers; 21) Nano Sponges for Drug Delivery and Medicinal Applications; 22) Molecular Technique to Understand Deep Microbial Diversity; 23) Methods and Compositions Based on Culturing Microorganisms in Low Sedimental Fluid Shear Conditions; 24) Secure Peer-to-Peer Networks for Scientific Information Sharing; 25) Multiplexer/Demultiplexer Loading Tool (MDMLT); 26) High-Rate Data-Capture for an Airborne Lidar System; 27) Wavefront Sensing Analysis of Grazing Incidence Optical Systems; 28) Foam-on-Tile Damage Model; 29) Instrument Package Manipulation Through the Generation and Use of an Attenuated-Fluent Gas Fold; 30) Multicolor Detectors for Ultrasensitive Long-Wave Imaging Cameras; 31) Lunar Reconnaissance Orbiter (LRO) Command and Data Handling Flight Electronics Subsystem; and 32) Electro-Optic Segment-Segment Sensors for Radio and Optical Telescopes.
A multipurpose camera system for monitoring Kīlauea Volcano, Hawai'i
Patrick, Matthew R.; Orr, Tim R.; Lee, Lopaka; Moniz, Cyril J.
2015-01-01
We describe a low-cost, compact multipurpose camera system designed for field deployment at active volcanoes that can be used either as a webcam (transmitting images back to an observatory in real-time) or as a time-lapse camera system (storing images onto the camera system for periodic retrieval during field visits). The system also has the capability to acquire high-definition video. The camera system uses a Raspberry Pi single-board computer and a 5-megapixel low-light (near-infrared sensitive) camera, as well as a small Global Positioning System (GPS) module to ensure accurate time-stamping of images. Custom Python scripts control the webcam and GPS unit and handle data management. The inexpensive nature of the system allows it to be installed at hazardous sites where it might be lost. Another major advantage of this camera system is that it provides accurate internal timing (independent of network connection) and, because a full Linux operating system and the Python programming language are available on the camera system itself, it has the versatility to be configured for the specific needs of the user. We describe example deployments of the camera at Kīlauea Volcano, Hawai‘i, to monitor ongoing summit lava lake activity.
Analyzing RCD30 Oblique Performance in a Production Environment
NASA Astrophysics Data System (ADS)
Soler, M. E.; Kornus, W.; Magariños, A.; Pla, M.
2016-06-01
In 2014 the Institut Cartogràfic i Geològic de Catalunya (ICGC) decided to incorporate digital oblique imagery in its portfolio in response to the growing demand for this product. The reason can be attributed to its useful applications in a wide variety of fields and, most recently, to an increasing interest in 3d modeling. The selection phase for a digital oblique camera led to the purchase of the Leica RCD30 Oblique system, an 80MPixel multispectral medium-format camera which consists of one Nadir camera and four oblique viewing cameras acquiring images at an off-Nadir angle of 35º. The system also has a multi-directional motion compensation on-board system to deliver the highest image quality. The emergence of airborne oblique cameras has run in parallel to the inclusion of computer vision algorithms into the traditional photogrammetric workflows. Such algorithms rely on having multiple views of the same area of interest and take advantage of the image redundancy for automatic feature extraction. The multiview capability is highly fostered by the use of oblique systems which capture simultaneously different points of view for each camera shot. Different companies and NMAs have started pilot projects to assess the capabilities of the 3D mesh that can be obtained using correlation techniques. Beyond a software prototyping phase, and taking into account the currently immature state of several components of the oblique imagery workflow, the ICGC has focused on deploying a real production environment with special interest on matching the performance and quality of the existing production lines based on classical Nadir images. This paper introduces different test scenarios and layouts to analyze the impact of different variables on the geometric and radiometric performance. Different variables such as flight altitude, side and forward overlap and ground control point measurements and location have been considered for the evaluation of aerial triangulation and stereo plotting. Furthermore, two different flight configurations have been designed to measure the quality of the absolute radiometric calibration and the resolving power of the system. To quantify the effective resolution power of RCD30 Oblique images, a tool based on the computation of the Line Spread Function has been developed. The tool processes a region of interest that contains a single contour in order to extract a numerical measure of edge smoothness for a same flight session. The ICGC is highly devoted to derive information from satellite and airborne multispectral remote sensing imagery. A seamless Normalized Difference Vegetation Index (NDVI) retrieved from Digital Metric Camera (DMC) reflectance imagery is one of the products of ICGC's portfolio. As an evolution of this well-defined product, this paper presents an evaluation of the absolute radiometric calibration of the RCD30 Oblique sensor. To assess the quality of the measure, the ICGC has developed a procedure based on simultaneous acquisition of RCD30 Oblique imagery and radiometric calibrated AISA (Airborne Hyperspectral Imaging System) imagery.
Evaluation of a high framerate multi-exposure laser speckle contrast imaging setup
NASA Astrophysics Data System (ADS)
Hultman, Martin; Fredriksson, Ingemar; Strömberg, Tomas; Larsson, Marcus
2018-02-01
We present a first evaluation of a new multi-exposure laser speckle contrast imaging (MELSCI) system for assessing spatial variations in the microcirculatory perfusion. The MELSCI system is based on a 1000 frames per second 1-megapixel camera connected to a field programmable gate arrays (FPGA) capable of producing MELSCI data in realtime. The imaging system is evaluated against a single point laser Doppler flowmetry (LDF) system during occlusionrelease provocations of the arm in five subjects. Perfusion is calculated from MELSCI data using current state-of-the-art inverse models. The analysis displayed a good agreement between measured and modeled data, with an average error below 6%. This strongly indicates that the applied model is capable of accurately describing the MELSCI data and that the acquired data is of high quality. Comparing readings from the occlusion-release provocation showed that the MELSCI perfusion was significantly correlated (R=0.83) to the single point LDF perfusion, clearly outperforming perfusion estimations based on a single exposure time. We conclude that the MELSCI system provides blood flow images of enhanced quality, taking us one step closer to a system that accurately can monitor dynamic changes in skin perfusion over a large area in real-time.
Visual Detection and Tracking System for a Spherical Amphibious Robot
Guo, Shuxiang; Pan, Shaowu; Shi, Liwei; Guo, Ping; He, Yanlin; Tang, Kun
2017-01-01
With the goal of supporting close-range observation tasks of a spherical amphibious robot, such as ecological observations and intelligent surveillance, a moving target detection and tracking system was designed and implemented in this study. Given the restrictions presented by the amphibious environment and the small-sized spherical amphibious robot, an industrial camera and vision algorithms using adaptive appearance models were adopted to construct the proposed system. To handle the problem of light scattering and absorption in the underwater environment, the multi-scale retinex with color restoration algorithm was used for image enhancement. Given the environmental disturbances in practical amphibious scenarios, the Gaussian mixture model was used to detect moving targets entering the field of view of the robot. A fast compressive tracker with a Kalman prediction mechanism was used to track the specified target. Considering the limited load space and the unique mechanical structure of the robot, the proposed vision system was fabricated with a low power system-on-chip using an asymmetric and heterogeneous computing architecture. Experimental results confirmed the validity and high efficiency of the proposed system. The design presented in this paper is able to meet future demands of spherical amphibious robots in biological monitoring and multi-robot cooperation. PMID:28420134
Visual Detection and Tracking System for a Spherical Amphibious Robot.
Guo, Shuxiang; Pan, Shaowu; Shi, Liwei; Guo, Ping; He, Yanlin; Tang, Kun
2017-04-15
With the goal of supporting close-range observation tasks of a spherical amphibious robot, such as ecological observations and intelligent surveillance, a moving target detection and tracking system was designed and implemented in this study. Given the restrictions presented by the amphibious environment and the small-sized spherical amphibious robot, an industrial camera and vision algorithms using adaptive appearance models were adopted to construct the proposed system. To handle the problem of light scattering and absorption in the underwater environment, the multi-scale retinex with color restoration algorithm was used for image enhancement. Given the environmental disturbances in practical amphibious scenarios, the Gaussian mixture model was used to detect moving targets entering the field of view of the robot. A fast compressive tracker with a Kalman prediction mechanism was used to track the specified target. Considering the limited load space and the unique mechanical structure of the robot, the proposed vision system was fabricated with a low power system-on-chip using an asymmetric and heterogeneous computing architecture. Experimental results confirmed the validity and high efficiency of the proposed system. The design presented in this paper is able to meet future demands of spherical amphibious robots in biological monitoring and multi-robot cooperation.
NASA Astrophysics Data System (ADS)
Lu, Mujie; Shang, Wenjie; Ji, Xinkai; Hua, Mingzhuang; Cheng, Kuo
2015-12-01
Nowadays, intelligent transportation system (ITS) has already become the new direction of transportation development. Traffic data, as a fundamental part of intelligent transportation system, is having a more and more crucial status. In recent years, video observation technology has been widely used in the field of traffic information collecting. Traffic flow information contained in video data has many advantages which is comprehensive and can be stored for a long time, but there are still many problems, such as low precision and high cost in the process of collecting information. This paper aiming at these problems, proposes a kind of traffic target detection method with broad applicability. Based on three different ways of getting video data, such as aerial photography, fixed camera and handheld camera, we develop a kind of intelligent analysis software which can be used to extract the macroscopic, microscopic traffic flow information in the video, and the information can be used for traffic analysis and transportation planning. For road intersections, the system uses frame difference method to extract traffic information, for freeway sections, the system uses optical flow method to track the vehicles. The system was applied in Nanjing, Jiangsu province, and the application shows that the system for extracting different types of traffic flow information has a high accuracy, it can meet the needs of traffic engineering observations and has a good application prospect.