Phase-stepped fringe projection by rotation about the camera's perspective center.
Huddart, Y R; Valera, J D; Weston, N J; Featherstone, T C; Moore, A J
2011-09-12
A technique to produce phase steps in a fringe projection system for shape measurement is presented. Phase steps are produced by introducing relative rotation between the object and the fringe projection probe (comprising a projector and camera) about the camera's perspective center. Relative motion of the object in the camera image can be compensated, because it is independent of the distance of the object from the camera, whilst the phase of the projected fringes is stepped due to the motion of the projector with respect to the object. The technique was validated with a static fringe projection system by moving an object on a coordinate measuring machine (CMM). The alternative approach, of rotating a lightweight and robust CMM-mounted fringe projection probe, is discussed. An experimental accuracy of approximately 1.5% of the projected fringe pitch was achieved, limited by the standard phase-stepping algorithms used rather than by the accuracy of the phase steps produced by the new technique.
ERIC Educational Resources Information Center
Cook, Tina; Hess, Else
2007-01-01
This article draws on the experience of three research projects where photography was used with children as a data collection method and presentation tool. It was used as a way of trying to enhance opportunities for adults to hear about topics from the perspective of children. The projects were not designed to investigate the use of cameras as a…
A Warping Framework for Wide-Angle Imaging and Perspective Manipulation
ERIC Educational Resources Information Center
Carroll, Robert E.
2013-01-01
Nearly all photographs are created with lenses that approximate an ideal pinhole camera--that is, a perspective projection. This projection has proven useful not only for creating realistic depictions, but also for its expressive flexibility. Beginning in the Renaissance, the notion of perspective gave artists a systematic way to represent…
Put a Brain in Your Camera: Nonstandard Perspectives and Computer Images in the Arts
ERIC Educational Resources Information Center
Reggini, Horacio C.
2011-01-01
Ever since the geometry of central perspective (conical projection) was developed in the XV century, it has been observed that mechanical application of the procedure leads to effects of distortion and exaggeration of shapes and sizes, which often make the result look unnatural. Similar observations are made with the optical projections obtained…
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.
1992-03-01
construction were completed and data, "’dm blue prints and physical measurements, was entered concurrent with the coding of routines for data retrieval. While...desirable for that view to accurately reflect what a person (or camera) would see if they were to stand at the same point in the physical world. To... physical dimensions. A parallel projection does not perform this scaling and is therefore not suitable to our application. B. GENERAL PERSPECTIVE
Projection model for flame chemiluminescence tomography based on lens imaging
NASA Astrophysics Data System (ADS)
Wan, Minggang; Zhuang, Jihui
2018-04-01
For flame chemiluminescence tomography (FCT) based on lens imaging, the projection model is essential because it formulates the mathematical relation between the flame projections captured by cameras and the chemiluminescence field, and, through this relation, the field is reconstructed. This work proposed the blurry-spot (BS) model, which takes more universal assumptions and has higher accuracy than the widely applied line-of-sight model. By combining the geometrical camera model and the thin-lens equation, the BS model takes into account perspective effect of the camera lens; by combining ray-tracing technique and Monte Carlo simulation, it also considers inhomogeneous distribution of captured radiance on the image plane. Performance of these two models in FCT was numerically compared, and results showed that using the BS model could lead to better reconstruction quality in wider application ranges.
Scale Space for Camera Invariant Features.
Puig, Luis; Guerrero, José J; Daniilidis, Kostas
2014-09-01
In this paper we propose a new approach to compute the scale space of any central projection system, such as catadioptric, fisheye or conventional cameras. Since these systems can be explained using a unified model, the single parameter that defines each type of system is used to automatically compute the corresponding Riemannian metric. This metric, is combined with the partial differential equations framework on manifolds, allows us to compute the Laplace-Beltrami (LB) operator, enabling the computation of the scale space of any central projection system. Scale space is essential for the intrinsic scale selection and neighborhood description in features like SIFT. We perform experiments with synthetic and real images to validate the generalization of our approach to any central projection system. We compare our approach with the best-existing methods showing competitive results in all type of cameras: catadioptric, fisheye, and perspective.
Geometric rectification of camera-captured document images.
Liang, Jian; DeMenthon, Daniel; Doermann, David
2008-04-01
Compared to typical scanners, handheld cameras offer convenient, flexible, portable, and non-contact image capture, which enables many new applications and breathes new life into existing ones. However, camera-captured documents may suffer from distortions caused by non-planar document shape and perspective projection, which lead to failure of current OCR technologies. We present a geometric rectification framework for restoring the frontal-flat view of a document from a single camera-captured image. Our approach estimates 3D document shape from texture flow information obtained directly from the image without requiring additional 3D/metric data or prior camera calibration. Our framework provides a unified solution for both planar and curved documents and can be applied in many, especially mobile, camera-based document analysis applications. Experiments show that our method produces results that are significantly more OCR compatible than the original images.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nazareth, D; Malhotra, H; French, S
Purpose: Breast radiotherapy, particularly electronic compensation, may involve large dose gradients and difficult patient positioning problems. We have developed a simple self-calibrating augmented-reality system, which assists in accurately and reproducibly positioning the patient, by displaying her live image from a single camera superimposed on the correct perspective projection of her 3D CT data. Our method requires only a standard digital camera capable of live-view mode, installed in the treatment suite at an approximately-known orientation and position (rotation R; translation T). Methods: A 10-sphere calibration jig was constructed and CT imaged to provide a 3D model. The (R,T) relating the cameramore » to the CT coordinate system were determined by acquiring a photograph of the jig and optimizing an objective function, which compares the true image points to points calculated with a given candidate R and T geometry. Using this geometric information, 3D CT patient data, viewed from the camera's perspective, is plotted using a Matlab routine. This image data is superimposed onto the real-time patient image, acquired by the camera, and displayed using standard live-view software. This enables the therapists to view both the patient's current and desired positions, and guide the patient into assuming the correct position. The method was evaluated using an in-house developed bolus-like breast phantom, mounted on a supporting platform, which could be tilted at various angles to simulate treatment-like geometries. Results: Our system allowed breast phantom alignment, with an accuracy of about 0.5 cm and 1 ± 0.5 degree. Better resolution could be possible using a camera with higher-zoom capabilities. Conclusion: We have developed an augmented-reality system, which combines a perspective projection of a CT image with a patient's real-time optical image. This system has the potential to improve patient setup accuracy during breast radiotherapy, and could possibly be used for other disease sites as well.« less
HOPIS: hybrid omnidirectional and perspective imaging system for mobile robots.
Lin, Huei-Yung; Wang, Min-Liang
2014-09-04
In this paper, we present a framework for the hybrid omnidirectional and perspective robot vision system. Based on the hybrid imaging geometry, a generalized stereo approach is developed via the construction of virtual cameras. It is then used to rectify the hybrid image pair using the perspective projection model. The proposed method not only simplifies the computation of epipolar geometry for the hybrid imaging system, but also facilitates the stereo matching between the heterogeneous image formation. Experimental results for both the synthetic data and real scene images have demonstrated the feasibility of our approach.
HOPIS: Hybrid Omnidirectional and Perspective Imaging System for Mobile Robots
Lin, Huei-Yung.; Wang, Min-Liang.
2014-01-01
In this paper, we present a framework for the hybrid omnidirectional and perspective robot vision system. Based on the hybrid imaging geometry, a generalized stereo approach is developed via the construction of virtual cameras. It is then used to rectify the hybrid image pair using the perspective projection model. The proposed method not only simplifies the computation of epipolar geometry for the hybrid imaging system, but also facilitates the stereo matching between the heterogeneous image formation. Experimental results for both the synthetic data and real scene images have demonstrated the feasibility of our approach. PMID:25192317
NASA Astrophysics Data System (ADS)
Mehrübeoğlu, Mehrübe; McLauchlan, Lifford
2006-02-01
The goal of this project was to detect the intensity of traffic on a road at different times of the day during daytime. Although the work presented utilized images from a section of a highway, the results of this project are intended for making decisions on the type of intervention necessary on any given road at different times for traffic control, such as installation of traffic signals, duration of red, green and yellow lights at intersections, and assignment of traffic control officers near school zones or other relevant locations. In this project, directional patterns are used to detect and count the number of cars in traffic images over a fixed area of the road to determine local traffic intensity. Directional patterns are chosen because they are simple and common to almost all moving vehicles. Perspective vision effects specific to each camera orientation has to be considered, as they affect the size and direction of patterns to be recognized. In this work, a simple and fast algorithm has been developed based on horizontal directional pattern matching and perspective vision adjustment. The results of the algorithm under various conditions are presented and compared in this paper. Using the developed algorithm, the traffic intensity can accurately be determined on clear days with average sized cars. The accuracy is reduced on rainy days when the camera lens contains raindrops, when there are very long vehicles, such as trucks or tankers, in the view, and when there is very low light around dusk or dawn.
Close Range Calibration of Long Focal Length Lenses in a Changing Environment
NASA Astrophysics Data System (ADS)
Robson, Stuart; MacDonald, Lindsay; Kyle, Stephen; Shortis, Mark R.
2016-06-01
University College London is currently developing a large-scale multi-camera system for dimensional control tasks in manufacturing, including part machining, assembly and tracking, as part of the Light Controlled Factory project funded by the UK Engineering and Physical Science Research Council. In parallel, as part of the EU LUMINAR project funded by the European Association of National Metrology Institutes, refraction models of the atmosphere in factory environments are being developed with the intent of modelling and eliminating the effects of temperature and other variations. The accuracy requirements for both projects are extremely demanding, so accordingly improvements in the modelling of both camera imaging and the measurement environment are essential. At the junction of these two projects lies close range camera calibration. The accurate and reliable calibration of cameras across a realistic range of atmospheric conditions in the factory environment is vital in order to eliminate systematic errors. This paper demonstrates the challenge of experimentally isolating environmental effects at the level of a few tens of microns. Longer lines of sight promote the use and calibration of a near perfect perspective projection from a Kern 75mm lens with maximum radial distortion of the order of 0.5m. Coordination of a reference target array, representing a manufactured part, is achieved to better than 0.1mm at a standoff of 8m. More widely, results contribute to better sensor understanding, improved mathematical modelling of factory environments and more reliable coordination of targets to 0.1mm and better over large volumes.
Calibration of the Nikon 200 for Close Range Photogrammetry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sheriff, Lassana; /City Coll., N.Y. /SLAC
2010-08-25
The overall objective of this project is to study the stability and reproducibility of the calibration parameters of the Nikon D200 camera with a Nikkor 20 mm lens for close-range photogrammetric surveys. The well known 'central perspective projection' model is used to determine the camera parameters for interior orientation. The Brown model extends it with the introduction of radial distortion and other less critical variables. The calibration process requires a dense network of targets to be photographed at different angles. For faster processing, reflective coded targets are chosen. Two scenarios have been used to check the reproducibility of the parameters.more » The first one is using a flat 2D wall with 141 coded targets and 12 custom targets that were previously measured with a laser tracker. The second one is a 3D Unistrut structure with a combination of coded targets and 3D reflective spheres. The study has shown that this setup is only stable during a short period of time. In conclusion, this camera is acceptable when calibrated before each use. Future work should include actual field tests and possible mechanical improvements, such as securing the lens to the camera body.« less
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Goal-oriented rectification of camera-based document images.
Stamatopoulos, Nikolaos; Gatos, Basilis; Pratikakis, Ioannis; Perantonis, Stavros J
2011-04-01
Document digitization with either flatbed scanners or camera-based systems results in document images which often suffer from warping and perspective distortions that deteriorate the performance of current OCR approaches. In this paper, we present a goal-oriented rectification methodology to compensate for undesirable document image distortions aiming to improve the OCR result. Our approach relies upon a coarse-to-fine strategy. First, a coarse rectification is accomplished with the aid of a computationally low cost transformation which addresses the projection of a curved surface to a 2-D rectangular area. The projection of the curved surface on the plane is guided only by the textual content's appearance in the document image while incorporating a transformation which does not depend on specific model primitives or camera setup parameters. Second, pose normalization is applied on the word level aiming to restore all the local distortions of the document image. Experimental results on various document images with a variety of distortions demonstrate the robustness and effectiveness of the proposed rectification methodology using a consistent evaluation methodology that encounters OCR accuracy and a newly introduced measure using a semi-automatic procedure.
Using virtual reality for science mission planning: A Mars Pathfinder case
NASA Technical Reports Server (NTRS)
Kim, Jacqueline H.; Weidner, Richard J.; Sacks, Allan L.
1994-01-01
NASA's Mars Pathfinder Project requires a Ground Data System (GDS) that supports both engineering and scientific payloads with reduced mission operations staffing, and short planning schedules. Also, successful surface operation of the lander camera requires efficient mission planning and accurate pointing of the camera. To meet these challenges, a new software strategy that integrates virtual reality technology with existing navigational ancillary information and image processing capabilities. The result is an interactive workstation based applications software that provides a high resolution, 3-dimensial, stereo display of Mars as if it were viewed through the lander camera. The design, implementation strategy and parametric specification phases for the development of this software were completed, and the prototype tested. When completed, the software will allow scientists and mission planners to access simulated and actual scenes of Mars' surface. The perspective from the lander camera will enable scientists to plan activities more accurately and completely. The application will also support the sequence and command generation process and will allow testing and verification of camera pointing commands via simulation.
Eccentricity error identification and compensation for high-accuracy 3D optical measurement
He, Dong; Liu, Xiaoli; Peng, Xiang; Ding, Yabin; Gao, Bruce Z
2016-01-01
The circular target has been widely used in various three-dimensional optical measurements, such as camera calibration, photogrammetry and structured light projection measurement system. The identification and compensation of the circular target systematic eccentricity error caused by perspective projection is an important issue for ensuring accurate measurement. This paper introduces a novel approach for identifying and correcting the eccentricity error with the help of a concentric circles target. Compared with previous eccentricity error correction methods, our approach does not require taking care of the geometric parameters of the measurement system regarding target and camera. Therefore, the proposed approach is very flexible in practical applications, and in particular, it is also applicable in the case of only one image with a single target available. The experimental results are presented to prove the efficiency and stability of the proposed approach for eccentricity error compensation. PMID:26900265
Eccentricity error identification and compensation for high-accuracy 3D optical measurement.
He, Dong; Liu, Xiaoli; Peng, Xiang; Ding, Yabin; Gao, Bruce Z
2013-07-01
The circular target has been widely used in various three-dimensional optical measurements, such as camera calibration, photogrammetry and structured light projection measurement system. The identification and compensation of the circular target systematic eccentricity error caused by perspective projection is an important issue for ensuring accurate measurement. This paper introduces a novel approach for identifying and correcting the eccentricity error with the help of a concentric circles target. Compared with previous eccentricity error correction methods, our approach does not require taking care of the geometric parameters of the measurement system regarding target and camera. Therefore, the proposed approach is very flexible in practical applications, and in particular, it is also applicable in the case of only one image with a single target available. The experimental results are presented to prove the efficiency and stability of the proposed approach for eccentricity error compensation.
Camera Perspective Bias in Videotaped Confessions: Evidence that Visual Attention Is a Mediator
ERIC Educational Resources Information Center
Ware, Lezlee J.; Lassiter, G. Daniel; Patterson, Stephen M.; Ransom, Michael R.
2008-01-01
Several experiments have demonstrated a "camera perspective bias" in evaluations of videotaped confessions: videotapes with the camera focused on the suspect lead to judgments of greater voluntariness than alternative presentation formats. The present research investigated potential mediators of this bias. Using eye tracking to measure visual…
Fisheye image rectification using spherical and digital distortion models
NASA Astrophysics Data System (ADS)
Li, Xin; Pi, Yingdong; Jia, Yanling; Yang, Yuhui; Chen, Zhiyong; Hou, Wenguang
2018-02-01
Fisheye cameras have been widely used in many applications including close range visual navigation and observation and cyber city reconstruction because its field of view is much larger than that of a common pinhole camera. This means that a fisheye camera can capture more information than a pinhole camera in the same scenario. However, the fisheye image contains serious distortion, which may cause trouble for human observers in recognizing the objects within. Therefore, in most practical applications, the fisheye image should be rectified to a pinhole perspective projection image to conform to human cognitive habits. The traditional mathematical model-based methods cannot effectively remove the distortion, but the digital distortion model can reduce the image resolution to some extent. Considering these defects, this paper proposes a new method that combines the physical spherical model and the digital distortion model. The distortion of fisheye images can be effectively removed according to the proposed approach. Many experiments validate its feasibility and effectiveness.
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.
SU-D-BRC-07: System Design for a 3D Volumetric Scintillation Detector Using SCMOS Cameras
DOE Office of Scientific and Technical Information (OSTI.GOV)
Darne, C; Robertson, D; Alsanea, F
2016-06-15
Purpose: The purpose of this project is to build a volumetric scintillation detector for quantitative imaging of 3D dose distributions of proton beams accurately in near real-time. Methods: The liquid scintillator (LS) detector consists of a transparent acrylic tank (20×20×20 cm{sup 3}) filled with a liquid scintillator that when irradiated with protons generates scintillation light. To track rapid spatial and dose variations in spot scanning proton beams we used three scientific-complementary metal-oxide semiconductor (sCMOS) imagers (2560×2160 pixels). The cameras collect optical signal from three orthogonal projections. To reduce system footprint two mirrors oriented at 45° to the tank surfaces redirectmore » scintillation light to cameras for capturing top and right views. Selection of fixed focal length objective lenses for these cameras was based on their ability to provide large depth of field (DoF) and required field of view (FoV). Multiple cross-hairs imprinted on the tank surfaces allow for image corrections arising from camera perspective and refraction. Results: We determined that by setting sCMOS to 16-bit dynamic range, truncating its FoV (1100×1100 pixels) to image the entire volume of the LS detector, and using 5.6 msec integration time imaging rate can be ramped up to 88 frames per second (fps). 20 mm focal length lens provides a 20 cm imaging DoF and 0.24 mm/pixel resolution. Master-slave camera configuration enable the slaves to initiate image acquisition instantly (within 2 µsec) after receiving a trigger signal. A computer with 128 GB RAM was used for spooling images from the cameras and can sustain a maximum recording time of 2 min per camera at 75 fps. Conclusion: The three sCMOS cameras are capable of high speed imaging. They can therefore be used for quick, high-resolution, and precise mapping of dose distributions from scanned spot proton beams in three dimensions.« less
Gan, Qi; Wang, Dong; Ye, Jian; Zhang, Zeshu; Wang, Xinrui; Hu, Chuanzhen; Shao, Pengfei; Xu, Ronald X.
2016-01-01
We propose a projective navigation system for fluorescence imaging and image display in a natural mode of visual perception. The system consists of an excitation light source, a monochromatic charge coupled device (CCD) camera, a host computer, a projector, a proximity sensor and a Complementary metal–oxide–semiconductor (CMOS) camera. With perspective transformation and calibration, our surgical navigation system is able to achieve an overall imaging speed higher than 60 frames per second, with a latency of 330 ms, a spatial sensitivity better than 0.5 mm in both vertical and horizontal directions, and a projection bias less than 1 mm. The technical feasibility of image-guided surgery is demonstrated in both agar-agar gel phantoms and an ex vivo chicken breast model embedding Indocyanine Green (ICG). The biological utility of the system is demonstrated in vivo in a classic model of ICG hepatic metabolism. Our benchtop, ex vivo and in vivo experiments demonstrate the clinical potential for intraoperative delineation of disease margin and image-guided resection surgery. PMID:27391764
Can we Use Low-Cost 360 Degree Cameras to Create Accurate 3d Models?
NASA Astrophysics Data System (ADS)
Barazzetti, L.; Previtali, M.; Roncoroni, F.
2018-05-01
360 degree cameras capture the whole scene around a photographer in a single shot. Cheap 360 cameras are a new paradigm in photogrammetry. The camera can be pointed to any direction, and the large field of view reduces the number of photographs. This paper aims to show that accurate metric reconstructions can be achieved with affordable sensors (less than 300 euro). The camera used in this work is the Xiaomi Mijia Mi Sphere 360, which has a cost of about 300 USD (January 2018). Experiments demonstrate that millimeter-level accuracy can be obtained during the image orientation and surface reconstruction steps, in which the solution from 360° images was compared to check points measured with a total station and laser scanning point clouds. The paper will summarize some practical rules for image acquisition as well as the importance of ground control points to remove possible deformations of the network during bundle adjustment, especially for long sequences with unfavorable geometry. The generation of orthophotos from images having a 360° field of view (that captures the entire scene around the camera) is discussed. Finally, the paper illustrates some case studies where the use of a 360° camera could be a better choice than a project based on central perspective cameras. Basically, 360° cameras become very useful in the survey of long and narrow spaces, as well as interior areas like small rooms.
Camera Trajectory fromWide Baseline Images
NASA Astrophysics Data System (ADS)
Havlena, M.; Torii, A.; Pajdla, T.
2008-09-01
Camera trajectory estimation, which is closely related to the structure from motion computation, is one of the fundamental tasks in computer vision. Reliable camera trajectory estimation plays an important role in 3D reconstruction, self localization, and object recognition. There are essential issues for a reliable camera trajectory estimation, for instance, choice of the camera and its geometric projection model, camera calibration, image feature detection and description, and robust 3D structure computation. Most of approaches rely on classical perspective cameras because of the simplicity of their projection models and ease of their calibration. However, classical perspective cameras offer only a limited field of view, and thus occlusions and sharp camera turns may cause that consecutive frames look completely different when the baseline becomes longer. This makes the image feature matching very difficult (or impossible) and the camera trajectory estimation fails under such conditions. These problems can be avoided if omnidirectional cameras, e.g. a fish-eye lens convertor, are used. The hardware which we are using in practice is a combination of Nikon FC-E9 mounted via a mechanical adaptor onto a Kyocera Finecam M410R digital camera. Nikon FC-E9 is a megapixel omnidirectional addon convertor with 180° view angle which provides images of photographic quality. Kyocera Finecam M410R delivers 2272×1704 images at 3 frames per second. The resulting combination yields a circular view of diameter 1600 pixels in the image. Since consecutive frames of the omnidirectional camera often share a common region in 3D space, the image feature matching is often feasible. On the other hand, the calibration of these cameras is non-trivial and is crucial for the accuracy of the resulting 3D reconstruction. We calibrate omnidirectional cameras off-line using the state-of-the-art technique and Mičušík's two-parameter model, that links the radius of the image point r to the angle θ of its corresponding rays w.r.t. the optical axis as θ = ar 1+br2 . After a successful calibration, we know the correspondence of the image points to the 3D optical rays in the coordinate system of the camera. The following steps aim at finding the transformation between the camera and the world coordinate systems, i.e. the pose of the camera in the 3D world, using 2D image matches. For computing 3D structure, we construct a set of tentative matches detecting different affine covariant feature regions including MSER, Harris Affine, and Hessian Affine in acquired images. These features are alternative to popular SIFT features and work comparably in our situation. Parameters of the detectors are chosen to limit the number of regions to 1-2 thousands per image. The detected regions are assigned local affine frames (LAF) and transformed into standard positions w.r.t. their LAFs. Discrete Cosine Descriptors are computed for each region in the standard position. Finally, mutual distances of all regions in one image and all regions in the other image are computed as the Euclidean distances of their descriptors and tentative matches are constructed by selecting the mutually closest pairs. Opposed to the methods using short baseline images, simpler image features which are not affine covariant cannot be used because the view point can change a lot between consecutive frames. Furthermore, feature matching has to be performed on the whole frame because no assumptions on the proximity of the consecutive projections can be made for wide baseline images. This is making the feature detection, description, and matching much more time-consuming than it is for short baseline images and limits the usage to low frame rate sequences when operating in real-time. Robust 3D structure can be computed by RANSAC which searches for the largest subset of the set of tentative matches which is, within a predefined threshold ", consistent with an epipolar geometry. We use ordered sampling as suggested in to draw 5-tuples from the list of tentative matches ordered ascendingly by the distance of their descriptors which may help to reduce the number of samples in RANSAC. From each 5-tuple, relative orientation is computed by solving the 5-point minimal relative orientation problem for calibrated cameras. Often, there are more models which are supported by a large number of matches. Thus the chance that the correct model, even if it has the largest support, will be found by running a single RANSAC is small. Work suggested to generate models by randomized sampling as in RANSAC but to use soft (kernel) voting for a parameter instead of looking for the maximal support. The best model is then selected as the one with the parameter closest to the maximum in the accumulator space. In our case, we vote in a two-dimensional accumulator for the estimated camera motion direction. However, unlike in, we do not cast votes directly by each sampled epipolar geometry but by the best epipolar geometries recovered by ordered sampling of RANSAC. With our technique, we could go up to the 98.5 % contamination of mismatches with comparable effort as simple RANSAC does for the contamination by 84 %. The relative camera orientation with the motion direction closest to the maximum in the voting space is finally selected. As already mentioned in the first paragraph, the use of camera trajectory estimates is quite wide. In we have introduced a technique for measuring the size of camera translation relatively to the observed scene which uses the dominant apical angle computed at the reconstructed scene points and is robust against mismatches. The experiments demonstrated that the measure can be used to improve the robustness of camera path computation and object recognition for methods which use a geometric, e.g. the ground plane, constraint such as does for the detection of pedestrians. Using the camera trajectories, perspective cutouts with stabilized horizon are constructed and an arbitrary object recognition routine designed to work with images acquired by perspective cameras can be used without any further modifications.
Research on inosculation between master of ceremonies or players and virtual scene in virtual studio
NASA Astrophysics Data System (ADS)
Li, Zili; Zhu, Guangxi; Zhu, Yaoting
2003-04-01
A technical principle about construction of virtual studio has been proposed where orientation tracker and telemeter has been used for improving conventional BETACAM pickup camera and connecting with the software module of the host. A model of virtual camera named Camera & Post-camera Coupling Pair has been put forward, which is different from the common model in computer graphics and has been bound to real BETACAM pickup camera for shooting. The formula has been educed to compute the foreground frame buffer image and the background frame buffer image of the virtual scene whose boundary is based on the depth information of target point of the real BETACAM pickup camera's projective ray. The effect of real-time consistency has been achieved between the video image sequences of the master of ceremonies or players and the CG video image sequences for the virtual scene in spatial position, perspective relationship and image object masking. The experimental result has shown that the technological scheme of construction of virtual studio submitted in this paper is feasible and more applicative and more effective than the existing technology to establish a virtual studio based on color-key and image synthesis with background using non-linear video editing technique.
Infrared Imaging Camera Final Report CRADA No. TC02061.0
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roos, E. V.; Nebeker, S.
This was a collaborative effort between the University of California, Lawrence Livermore National Laboratory (LLNL) and Cordin Company (Cordin) to enhance the U.S. ability to develop a commercial infrared camera capable of capturing high-resolution images in a l 00 nanoseconds (ns) time frame. The Department of Energy (DOE), under an Initiative for Proliferation Prevention (IPP) project, funded the Russian Federation Nuclear Center All-Russian Scientific Institute of Experimental Physics (RFNC-VNIIEF) in Sarov. VNIIEF was funded to develop a prototype commercial infrared (IR) framing camera and to deliver a prototype IR camera to LLNL. LLNL and Cordin were partners with VNIIEF onmore » this project. A prototype IR camera was delivered by VNIIEF to LLNL in December 2006. In June of 2007, LLNL and Cordin evaluated the camera and the test results revealed that the camera exceeded presently available commercial IR cameras. Cordin believes that the camera can be sold on the international market. The camera is currently being used as a scientific tool within Russian nuclear centers. This project was originally designated as a two year project. The project was not started on time due to changes in the IPP project funding conditions; the project funding was re-directed through the International Science and Technology Center (ISTC), which delayed the project start by over one year. The project was not completed on schedule due to changes within the Russian government export regulations. These changes were directed by Export Control regulations on the export of high technology items that can be used to develop military weapons. The IR camera was on the list that export controls required. The ISTC and Russian government, after negotiations, allowed the delivery of the camera to LLNL. There were no significant technical or business changes to the original project.« less
Camera perspective bias in videotaped confessions: experimental evidence of its perceptual basis.
Ratcliff, Jennifer J; Lassiter, G Daniel; Schmidt, Heather C; Snyder, Celeste J
2006-12-01
The camera perspective from which a criminal confession is videotaped influences later assessments of its voluntariness and the suspect's guilt. Previous research has suggested that this camera perspective bias is rooted in perceptual rather than conceptual processes, but these data are strictly correlational. In 3 experiments, the authors directly manipulated perceptual processing to provide stronger evidence of its mediational role. Prior to viewing a videotape of a simulated confession, participants were shown a photograph of the confessor's apparent victim. Participants in a perceptual interference condition were instructed to visualize the image of the victim in their minds while viewing the videotape; participants in a conceptual interference condition were instructed instead to rehearse an 8-digit number. Because mental imagery and actual perception draw on the same available resources, the authors anticipated that the former, but not the latter, interference task would disrupt the camera perspective bias, if indeed it were perceptually mediated. Results supported this conclusion.
3D digital image correlation using a single 3CCD colour camera and dichroic filter
NASA Astrophysics Data System (ADS)
Zhong, F. Q.; Shao, X. X.; Quan, C.
2018-04-01
In recent years, three-dimensional digital image correlation methods using a single colour camera have been reported. In this study, we propose a simplified system by employing a dichroic filter (DF) to replace the beam splitter and colour filters. The DF can be used to combine two views from different perspectives reflected by two planar mirrors and eliminate their interference. A 3CCD colour camera is then used to capture two different views simultaneously via its blue and red channels. Moreover, the measurement accuracy of the proposed method is higher since the effect of refraction is reduced. Experiments are carried out to verify the effectiveness of the proposed method. It is shown that the interference between the blue and red views is insignificant. In addition, the measurement accuracy of the proposed method is validated on the rigid body displacement. The experimental results demonstrate that the measurement accuracy of the proposed method is higher compared with the reported methods using a single colour camera. Finally, the proposed method is employed to measure the in- and out-of-plane displacements of a loaded plastic board. The re-projection errors of the proposed method are smaller than those of the reported methods using a single colour camera.
Badry, Dorothy; Felske, Aileen Wight
2013-01-01
Objective The Brightening Our Home Fires (BOHF) project was conceptualized as an exploratory project to examine the issue of the prevention of foetal alcohol spectrum disorder (FASD) from a women's health perspective in the Northwest Territories (NT). While dominant discourse suggests that FASD is preventable by abstention from alcohol during pregnancy, a broader perspective would indicate that alcohol and pregnancy is a far more complex issue, that is, bound in location, economics, social and cultural views of health. This project was prevention focused and a social determinant of health (SDH) perspective informed this research. Methods The BOHF project was a qualitative research project using a participatory action research framework to examine women's health and healing in the north. The methodology utilized was Photovoice. Women were provided training in digital photography and given cameras to use and keep. The primary research question utilized was: What does health and healing look like for you in your community? Women described their photos, individually or in groups around this central topic. This research was FASD informed, and women participants were aware this was an FASD prevention funded project whose approach focused on a broader context of health and lived experience. Results This project drew 30 participants from: Yellowknife, Lutsel ‘ke, Behchokö and Ulukhaktok. These four different communities across the NT represented Dene and Inuit culture. The qualitative data analysis offered themes of importance to women's health in the north including: land and tradition; housing; poverty; food; family; health, mental health and trauma, and travel. Photovoice provides a non-threatening way to engage in dialogue on complex health and social issues. PMID:23984290
Efficient structure from motion on large scenes using UAV with position and pose information
NASA Astrophysics Data System (ADS)
Teng, Xichao; Yu, Qifeng; Shang, Yang; Luo, Jing; Wang, Gang
2018-04-01
In this paper, we exploit prior information from global positioning systems and inertial measurement units to speed up the process of large scene reconstruction from images acquired by Unmanned Aerial Vehicles. We utilize weak pose information and intrinsic parameter to obtain the projection matrix for each view. As compared to unmanned aerial vehicles' flight altitude, topographic relief can usually be ignored, we assume that the scene is flat and use weak perspective camera to get projective transformations between two views. Furthermore, we propose an overlap criterion and select potentially matching view pairs between projective transformed views. A robust global structure from motion method is used for image based reconstruction. Our real world experiments show that the approach is accurate, scalable and computationally efficient. Moreover, projective transformations between views can also be used to eliminate false matching.
Automated Mobile System for Accurate Outdoor Tree Crop Enumeration Using an Uncalibrated Camera.
Nguyen, Thuy Tuong; Slaughter, David C; Hanson, Bradley D; Barber, Andrew; Freitas, Amy; Robles, Daniel; Whelan, Erin
2015-07-28
This paper demonstrates an automated computer vision system for outdoor tree crop enumeration in a seedling nursery. The complete system incorporates both hardware components (including an embedded microcontroller, an odometry encoder, and an uncalibrated digital color camera) and software algorithms (including microcontroller algorithms and the proposed algorithm for tree crop enumeration) required to obtain robust performance in a natural outdoor environment. The enumeration system uses a three-step image analysis process based upon: (1) an orthographic plant projection method integrating a perspective transform with automatic parameter estimation; (2) a plant counting method based on projection histograms; and (3) a double-counting avoidance method based on a homography transform. Experimental results demonstrate the ability to count large numbers of plants automatically with no human effort. Results show that, for tree seedlings having a height up to 40 cm and a within-row tree spacing of approximately 10 cm, the algorithms successfully estimated the number of plants with an average accuracy of 95.2% for trees within a single image and 98% for counting of the whole plant population in a large sequence of images.
Automated Mobile System for Accurate Outdoor Tree Crop Enumeration Using an Uncalibrated Camera
Nguyen, Thuy Tuong; Slaughter, David C.; Hanson, Bradley D.; Barber, Andrew; Freitas, Amy; Robles, Daniel; Whelan, Erin
2015-01-01
This paper demonstrates an automated computer vision system for outdoor tree crop enumeration in a seedling nursery. The complete system incorporates both hardware components (including an embedded microcontroller, an odometry encoder, and an uncalibrated digital color camera) and software algorithms (including microcontroller algorithms and the proposed algorithm for tree crop enumeration) required to obtain robust performance in a natural outdoor environment. The enumeration system uses a three-step image analysis process based upon: (1) an orthographic plant projection method integrating a perspective transform with automatic parameter estimation; (2) a plant counting method based on projection histograms; and (3) a double-counting avoidance method based on a homography transform. Experimental results demonstrate the ability to count large numbers of plants automatically with no human effort. Results show that, for tree seedlings having a height up to 40 cm and a within-row tree spacing of approximately 10 cm, the algorithms successfully estimated the number of plants with an average accuracy of 95.2% for trees within a single image and 98% for counting of the whole plant population in a large sequence of images. PMID:26225982
NASA Astrophysics Data System (ADS)
Wong, Erwin
2000-03-01
Traditional methods of linear based imaging limits the viewer to a single fixed-point perspective. By means of a single lens multiple perspective mirror system, a 360-degree representation of the area around the camera is reconstructed. This reconstruction is used overcome the limitations of a traditional camera by providing the viewer with many different perspectives. By constructing the mirror into a hemispherical surface with multiple focal lengths at various diameters on the mirror, and by placing a parabolic mirror overhead, a stereoscopic image can be extracted from the image captured by a high-resolution camera placed beneath the mirror. Image extraction and correction is made by computer processing of the image obtained by camera; the image present up to five distinguishable different viewpoints that a computer can extrapolate pseudo- perspective data from. Geometric and depth for field can be extrapolated via comparison and isolation of objects within a virtual scene post processed by the computer. Combining data with scene rendering software provides the viewer with the ability to choose a desired viewing position, multiple dynamic perspectives, and virtually constructed perspectives based on minimal existing data. An examination into the workings of the mirror relay system is provided, including possible image extrapolation and correctional methods. Generation of data and virtual interpolated and constructed data is also mentioned.
Robust human detection, tracking, and recognition in crowded urban areas
NASA Astrophysics Data System (ADS)
Chen, Hai-Wen; McGurr, Mike
2014-06-01
In this paper, we present algorithms we recently developed to support an automated security surveillance system for very crowded urban areas. In our approach for human detection, the color features are obtained by taking the difference of R, G, B spectrum and converting R, G, B to HSV (Hue, Saturation, Value) space. Morphological patch filtering and regional minimum and maximum segmentation on the extracted features are applied for target detection. The human tracking process approach includes: 1) Color and intensity feature matching track candidate selection; 2) Separate three parallel trackers for color, bright (above mean intensity), and dim (below mean intensity) detections, respectively; 3) Adaptive track gate size selection for reducing false tracking probability; and 4) Forward position prediction based on previous moving speed and direction for continuing tracking even when detections are missed from frame to frame. The Human target recognition is improved with a Super-Resolution Image Enhancement (SRIE) process. This process can improve target resolution by 3-5 times and can simultaneously process many targets that are tracked. Our approach can project tracks from one camera to another camera with a different perspective viewing angle to obtain additional biometric features from different perspective angles, and to continue tracking the same person from the 2nd camera even though the person moved out of the Field of View (FOV) of the 1st camera with `Tracking Relay'. Finally, the multiple cameras at different view poses have been geo-rectified to nadir view plane and geo-registered with Google- Earth (or other GIS) to obtain accurate positions (latitude, longitude, and altitude) of the tracked human for pin-point targeting and for a large area total human motion activity top-view. Preliminary tests of our algorithms indicate than high probability of detection can be achieved for both moving and stationary humans. Our algorithms can simultaneously track more than 100 human targets with averaged tracking period (time length) longer than the performance of the current state-of-the-art.
NASA Astrophysics Data System (ADS)
Dzwierzynska, Jolanta
2017-12-01
The use of perspective images, especially historical photographs for retrieving information about presented architectural environment is a fast developing field recently. The photography image is a perspective image with secure geometrical connection with reality, therefore it is possible to reverse this process. The aim of the herby study is establishing requirements which a photographic perspective representation should meet for a reconstruction purpose, as well as determination of base elements of perspective such as a horizon line and a circle of depth, which is a key issue in any reconstruction. The starting point in the reconstruction process is geometrical analysis of the photograph, especially determination of the kind of perspective projection applied, which is defined by the building location towards a projection plane. Next, proper constructions can be used. The paper addresses the problem of establishing base elements of perspective on the basis of the photograph image in the case when camera calibration is impossible to establish. It presents different geometric construction methods selected dependently on the starting assumptions. Therefore, the methods described in the paper seem to be universal. Moreover, they can be used even in the case of poor quality photographs with poor perspective geometry. Such constructions can be realized with computer aid when the photographs are in digital form as it is presented in the paper. The accuracy of the applied methods depends on the photography image accuracy, as well as drawing accuracy, however, it is sufficient for further reconstruction. Establishing base elements of perspective presented in the paper is especially useful in difficult cases of reconstruction, when one lacks information about reconstructed architectural form and it is necessary to lean on solid geometry.
Haverkort, J J Mark; Leenen, Luke P H
2017-10-01
Presently used evaluation techniques rely on 3 traditional dimensions: reports from observers, registration system data, and observational cameras. Some of these techniques are observer-dependent and are not reproducible for a second review. This proof-of-concept study aimed to test the feasibility of extending evaluation to a fourth dimension, the patient's perspective. Footage was obtained during a large, full-scale hospital trauma drill. Two mock victims were equipped with point-of-view cameras filming from the patient's head. Based on the Major Incident Hospital's first experience during the drill, a protocol was developed for a prospective, standardized method to evaluate a hospital's major incident response from the patient's perspective. The protocol was then tested in a second drill for its feasibility. New insights were gained after review of the footage. The traditional observer missed some of the evaluation points, which were seen on the point-of-view cameras. The information gained from the patient's perspective proved to be implementable into the designed protocol. Use of point-of-view camera recordings from a mock patient's perspective is a valuable addition to traditional evaluation of trauma drills and trauma care. Protocols should be designed to optimize and objectify judgement of such footage. (Disaster Med Public Health Preparedness. 2017;11:594-599).
The Use of the Nelder-Mead Method in Determining Projection Parameters for Globe Photographs
NASA Astrophysics Data System (ADS)
Gede, M.
2009-04-01
A photo of a terrestrial or celestial globe can be handled as a map. The only hard issue is its projection: the so-called Tilted Perspective Projection which, if the optical axis of the photo intersects the globe's centre, is simplified to the Vertical Near-Side Perspective Projection. When georeferencing such a photo, the exact parameters of the projections are also needed. These parameters depend on the position of the viewpoint of the camera. Several hundreds of globe photos had to be georeferenced during the Virtual Globes Museum project, which made necessary to automatize the calculation of the projection parameters. The author developed a program for this task which uses the Nelder-Mead Method in order to find the optimum parameters when a set of control points are given as input. The Nelder-Mead method is a numerical algorithm for minimizing a function in a many-dimensional space. The function in the present application is the average error of the control points calculated from the actual values of parameters. The parameters are the geographical coordinates of the projection centre, the image coordinates of the same point, the rotation of the projection, the height of the perspective point and the scale of the photo (calculated in pixels/km). The program reads the Global Mappers Ground Control Point (.GCP) file format as input and creates projection description files (.PRJ) for the same software. The initial values of the geographical coordinates of the projection centre are calculated as the average of the control points, while the other parameters are set to experimental values which represent the most common circumstances of taking a globe photograph. The algorithm runs until the change of the parameters sinks below a pre-defined limit. The minimum search can be refined by using the previous result parameter set as new initial values. This paper introduces the calculation mechanism and examples of the usage. Other possible other usages of the method are also discussed.
Development of infrared scene projectors for testing fire-fighter cameras
NASA Astrophysics Data System (ADS)
Neira, Jorge E.; Rice, Joseph P.; Amon, Francine K.
2008-04-01
We have developed two types of infrared scene projectors for hardware-in-the-loop testing of thermal imaging cameras such as those used by fire-fighters. In one, direct projection, images are projected directly into the camera. In the other, indirect projection, images are projected onto a diffuse screen, which is then viewed by the camera. Both projectors use a digital micromirror array as the spatial light modulator, in the form of a Micromirror Array Projection System (MAPS) engine having resolution of 800 x 600 with mirrors on a 17 micrometer pitch, aluminum-coated mirrors, and a ZnSe protective window. Fire-fighter cameras are often based upon uncooled microbolometer arrays and typically have resolutions of 320 x 240 or lower. For direct projection, we use an argon-arc source, which provides spectral radiance equivalent to a 10,000 Kelvin blackbody over the 7 micrometer to 14 micrometer wavelength range, to illuminate the micromirror array. For indirect projection, an expanded 4 watt CO II laser beam at a wavelength of 10.6 micrometers illuminates the micromirror array and the scene formed by the first-order diffracted light from the array is projected onto a diffuse aluminum screen. In both projectors, a well-calibrated reference camera is used to provide non-uniformity correction and brightness calibration of the projected scenes, and the fire-fighter cameras alternately view the same scenes. In this paper, we compare the two methods for this application and report on our quantitative results. Indirect projection has an advantage of being able to more easily fill the wide field of view of the fire-fighter cameras, which typically is about 50 degrees. Direct projection more efficiently utilizes the available light, which will become important in emerging multispectral and hyperspectral applications.
NASA Technical Reports Server (NTRS)
Hussey, K. J.; Hall, J. R.; Mortensen, R. A.
1986-01-01
Image processing methods and software used to animate nonimaging remotely sensed data on cloud cover are described. Three FORTRAN programs were written in the VICAR2/TAE image processing domain to perform 3D perspective rendering, to interactively select parameters controlling the projection, and to interpolate parameter sets for animation images between key frames. Operation of the 3D programs and transferring the images to film is automated using executive control language and custom hardware to link the computer and camera.
Image-Based Visual Servoing for Robotic Systems: A Nonlinear Lyapunov-Based Control Approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dixon, Warren
2004-06-01
There is significant motivation to provide robotic systems with improved autonomy as a means to significantly accelerate deactivation and decommissioning (D&D) operations while also reducing the associated costs, removing human operators from hazardous environments, and reducing the required burden and skill of human operators. To achieve improved autonomy, this project focused on the basic science challenges leading to the development of visual servo controllers. The challenge in developing these controllers is that a camera provides 2-dimensional image information about the 3-dimensional Euclidean-space through a perspective (range dependent) projection that can be corrupted by uncertainty in the camera calibration matrix andmore » by disturbances such as nonlinear radial distortion. Disturbances in this relationship (i.e., corruption in the sensor information) propagate erroneous information to the feedback controller of the robot, leading to potentially unpredictable task execution. This research project focused on the development of a visual servo control methodology that targets compensating for disturbances in the camera model (i.e., camera calibration and the recovery of range information) as a means to achieve predictable response by the robotic system operating in unstructured environments. The fundamental idea is to use nonlinear Lyapunov-based techniques along with photogrammetry methods to overcome the complex control issues and alleviate many of the restrictive assumptions that impact current robotic applications. The outcome of this control methodology is a plug-and-play visual servoing control module that can be utilized in conjunction with current technology such as feature recognition and extraction to enable robotic systems with the capabilities of increased accuracy, autonomy, and robustness, with a larger field of view (and hence a larger workspace). The developed methodology has been reported in numerous peer-reviewed publications and the performance and enabling capabilities of the resulting visual servo control modules have been demonstrated on mobile robot and robot manipulator platforms.« less
Quasi-eccentricity error modeling and compensation in vision metrology
NASA Astrophysics Data System (ADS)
Shen, Yijun; Zhang, Xu; Cheng, Wei; Zhu, Limin
2018-04-01
Circular targets are commonly used in vision applications for its detection accuracy and robustness. The eccentricity error of the circular target caused by perspective projection is one of the main factors of measurement error which needs to be compensated in high-accuracy measurement. In this study, the impact of the lens distortion on the eccentricity error is comprehensively investigated. The traditional eccentricity error turns to a quasi-eccentricity error in the non-linear camera model. The quasi-eccentricity error model is established by comparing the quasi-center of the distorted ellipse with the true projection of the object circle center. Then, an eccentricity error compensation framework is proposed which compensates the error by iteratively refining the image point to the true projection of the circle center. Both simulation and real experiment confirm the effectiveness of the proposed method in several vision applications.
Evaluation of the Quality of Action Cameras with Wide-Angle Lenses in Uav Photogrammetry
NASA Astrophysics Data System (ADS)
Hastedt, H.; Ekkel, T.; Luhmann, T.
2016-06-01
The application of light-weight cameras in UAV photogrammetry is required due to restrictions in payload. In general, consumer cameras with normal lens type are applied to a UAV system. The availability of action cameras, like the GoPro Hero4 Black, including a wide-angle lens (fish-eye lens) offers new perspectives in UAV projects. With these investigations, different calibration procedures for fish-eye lenses are evaluated in order to quantify their accuracy potential in UAV photogrammetry. Herewith the GoPro Hero4 is evaluated using different acquisition modes. It is investigated to which extent the standard calibration approaches in OpenCV or Agisoft PhotoScan/Lens can be applied to the evaluation processes in UAV photogrammetry. Therefore different calibration setups and processing procedures are assessed and discussed. Additionally a pre-correction of the initial distortion by GoPro Studio and its application to the photogrammetric purposes will be evaluated. An experimental setup with a set of control points and a prospective flight scenario is chosen to evaluate the processing results using Agisoft PhotoScan. Herewith it is analysed to which extent a pre-calibration and pre-correction of a GoPro Hero4 will reinforce the reliability and accuracy of a flight scenario.
The research on calibration methods of dual-CCD laser three-dimensional human face scanning system
NASA Astrophysics Data System (ADS)
Wang, Jinjiang; Chang, Tianyu; Ge, Baozhen; Tian, Qingguo; Yang, Fengting; Shi, Shendong
2013-09-01
In this paper, on the basis of considering the performance advantages of two-step method, we combines the stereo matching of binocular stereo vision with active laser scanning to calibrate the system. Above all, we select a reference camera coordinate system as the world coordinate system and unity the coordinates of two CCD cameras. And then obtain the new perspective projection matrix (PPM) of each camera after the epipolar rectification. By those, the corresponding epipolar equation of two cameras can be defined. So by utilizing the trigonometric parallax method, we can measure the space point position after distortion correction and achieve stereo matching calibration between two image points. Experiments verify that this method can improve accuracy and system stability is guaranteed. The stereo matching calibration has a simple process with low-cost, and simplifies regular maintenance work. It can acquire 3D coordinates only by planar checkerboard calibration without the need of designing specific standard target or using electronic theodolite. It is found that during the experiment two-step calibration error and lens distortion lead to the stratification of point cloud data. The proposed calibration method which combining active line laser scanning and binocular stereo vision has the both advantages of them. It has more flexible applicability. Theory analysis and experiment shows the method is reasonable.
ERIC Educational Resources Information Center
Bird, Jo; Colliver, Yeshe; Edwards, Susan
2014-01-01
Participatory research methods argue that young children should be enabled to contribute their perspectives on research seeking to understand their worldviews. Visual research methods, including the use of still and video cameras with young children have been viewed as particularly suited to this aim because cameras have been considered easy and…
Self calibrating monocular camera measurement of traffic parameters.
DOT National Transportation Integrated Search
2009-12-01
This proposed project will extend the work of previous projects that have developed algorithms and software : to measure traffic speed under adverse conditions using un-calibrated cameras. The present implementation : uses the WSDOT CCTV cameras moun...
HDR video synthesis for vision systems in dynamic scenes
NASA Astrophysics Data System (ADS)
Shopovska, Ivana; Jovanov, Ljubomir; Goossens, Bart; Philips, Wilfried
2016-09-01
High dynamic range (HDR) image generation from a number of differently exposed low dynamic range (LDR) images has been extensively explored in the past few decades, and as a result of these efforts a large number of HDR synthesis methods have been proposed. Since HDR images are synthesized by combining well-exposed regions of the input images, one of the main challenges is dealing with camera or object motion. In this paper we propose a method for the synthesis of HDR video from a single camera using multiple, differently exposed video frames, with circularly alternating exposure times. One of the potential applications of the system is in driver assistance systems and autonomous vehicles, involving significant camera and object movement, non- uniform and temporally varying illumination, and the requirement of real-time performance. To achieve these goals simultaneously, we propose a HDR synthesis approach based on weighted averaging of aligned radiance maps. The computational complexity of high-quality optical flow methods for motion compensation is still pro- hibitively high for real-time applications. Instead, we rely on more efficient global projective transformations to solve camera movement, while moving objects are detected by thresholding the differences between the trans- formed and brightness adapted images in the set. To attain temporal consistency of the camera motion in the consecutive HDR frames, the parameters of the perspective transformation are stabilized over time by means of computationally efficient temporal filtering. We evaluated our results on several reference HDR videos, on synthetic scenes, and using 14-bit raw images taken with a standard camera.
Vision Aided Inertial Navigation System Augmented with a Coded Aperture
2011-03-24
as the change in blur at different distances from the pixel plane can be inferred. Cameras with a micro lens array (called plenoptic cameras...images from 8 slightly different perspectives [14,43]. Dappled photography is a similar to the plenoptic camera approach except that a cosine mask
Camera calibration based on the back projection process
NASA Astrophysics Data System (ADS)
Gu, Feifei; Zhao, Hong; Ma, Yueyang; Bu, Penghui
2015-12-01
Camera calibration plays a crucial role in 3D measurement tasks of machine vision. In typical calibration processes, camera parameters are iteratively optimized in the forward imaging process (FIP). However, the results can only guarantee the minimum of 2D projection errors on the image plane, but not the minimum of 3D reconstruction errors. In this paper, we propose a universal method for camera calibration, which uses the back projection process (BPP). In our method, a forward projection model is used to obtain initial intrinsic and extrinsic parameters with a popular planar checkerboard pattern. Then, the extracted image points are projected back into 3D space and compared with the ideal point coordinates. Finally, the estimation of the camera parameters is refined by a non-linear function minimization process. The proposed method can obtain a more accurate calibration result, which is more physically useful. Simulation and practical data are given to demonstrate the accuracy of the proposed method.
2007-09-01
the projective camera matrix (P) which is a 3x4 matrix that is represents both the intrinsic and extrinsic parameters of a camera. It is used to...K contains the intrinsic parameters of the camera and |R t⎡ ⎤⎣ ⎦ represents the extrinsic parameters of the camera. By definition, the extrinsic ... extrinsic parameters are known then the camera is said to be calibrated. If only the intrinsic parameters are known, then the projective camera can
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.
Depth measurements through controlled aberrations of projected patterns.
Birch, Gabriel C; Tyo, J Scott; Schwiegerling, Jim
2012-03-12
Three-dimensional displays have become increasingly present in consumer markets. However, the ability to capture three-dimensional images in space confined environments and without major modifications to current cameras is uncommon. Our goal is to create a simple modification to a conventional camera that allows for three dimensional reconstruction. We require such an imaging system have imaging and illumination paths coincident. Furthermore, we require that any three-dimensional modification to a camera also permits full resolution 2D image capture.Here we present a method of extracting depth information with a single camera and aberrated projected pattern. A commercial digital camera is used in conjunction with a projector system with astigmatic focus to capture images of a scene. By using an astigmatic projected pattern we can create two different focus depths for horizontal and vertical features of a projected pattern, thereby encoding depth. By designing an aberrated projected pattern, we are able to exploit this differential focus in post-processing designed to exploit the projected pattern and optical system. We are able to correlate the distance of an object at a particular transverse position from the camera to ratios of particular wavelet coefficients.We present our information regarding construction, calibration, and images produced by this system. The nature of linking a projected pattern design and image processing algorithms will be discussed.
Wind-Sculpted Vicinity After Opportunity's Sol 1797 Drive (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11820 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11820 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, full-circle view of the rover's surroundings just after driving 111 meters (364 feet) on the 1,797th Martian day, or sol, of Opportunity's surface mission (Feb. 12, 2009). North is at the center; south at both ends. This view is the right-eye member of a stereo pair presented as a cylindrical-perspective projection with geometric seam correction. Tracks from the drive recede northward across dark-toned sand ripples in the Meridiani Planum region of Mars. Patches of lighter-toned bedrock are visible on the left and right sides of the image. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). This view is presented as a cylindrical-perspective projection with geometric seam correction.Quality Assessment of 3d Reconstruction Using Fisheye and Perspective Sensors
NASA Astrophysics Data System (ADS)
Strecha, C.; Zoller, R.; Rutishauser, S.; Brot, B.; Schneider-Zapp, K.; Chovancova, V.; Krull, M.; Glassey, L.
2015-03-01
Recent mathematical advances, growing alongside the use of unmanned aerial vehicles, have not only overcome the restriction of roll and pitch angles during flight but also enabled us to apply non-metric cameras in photogrammetric method, providing more flexibility for sensor selection. Fisheye cameras, for example, advantageously provide images with wide coverage; however, these images are extremely distorted and their non-uniform resolutions make them more difficult to use for mapping or terrestrial 3D modelling. In this paper, we compare the usability of different camera-lens combinations, using the complete workflow implemented in Pix4Dmapper to achieve the final terrestrial reconstruction result of a well-known historical site in Switzerland: the Chillon Castle. We assess the accuracy of the outcome acquired by consumer cameras with perspective and fisheye lenses, comparing the results to a laser scanner point cloud.
Combining color and shape information for illumination-viewpoint invariant object recognition.
Diplaros, Aristeidis; Gevers, Theo; Patras, Ioannis
2006-01-01
In this paper, we propose a new scheme that merges color- and shape-invariant information for object recognition. To obtain robustness against photometric changes, color-invariant derivatives are computed first. Color invariance is an important aspect of any object recognition scheme, as color changes considerably with the variation in illumination, object pose, and camera viewpoint. These color invariant derivatives are then used to obtain similarity invariant shape descriptors. Shape invariance is equally important as, under a change in camera viewpoint and object pose, the shape of a rigid object undergoes a perspective projection on the image plane. Then, the color and shape invariants are combined in a multidimensional color-shape context which is subsequently used as an index. As the indexing scheme makes use of a color-shape invariant context, it provides a high-discriminative information cue robust against varying imaging conditions. The matching function of the color-shape context allows for fast recognition, even in the presence of object occlusion and cluttering. From the experimental results, it is shown that the method recognizes rigid objects with high accuracy in 3-D complex scenes and is robust against changing illumination, camera viewpoint, object pose, and noise.
Validation of geometric models for fisheye lenses
NASA Astrophysics Data System (ADS)
Schneider, D.; Schwalbe, E.; Maas, H.-G.
The paper focuses on the photogrammetric investigation of geometric models for different types of optical fisheye constructions (equidistant, equisolid-angle, sterographic and orthographic projection). These models were implemented and thoroughly tested in a spatial resection and a self-calibrating bundle adjustment. For this purpose, fisheye images were taken with a Nikkor 8 mm fisheye lens on a Kodak DSC 14n Pro digital camera in a hemispherical calibration room. Both, the spatial resection and the bundle adjustment resulted in a standard deviation of unit weight of 1/10 pixel with a suitable set of simultaneous calibration parameters introduced into the camera model. The camera-lens combination was treated with all of the four basic models mentioned above. Using the same set of additional lens distortion parameters, the differences between the models can largely be compensated, delivering almost the same precision parameters. The relative object space precision obtained from the bundle adjustment was ca. 1:10 000 of the object dimensions. This value can be considered as a very satisfying result, as fisheye images generally have a lower geometric resolution as a consequence of their large field of view and also have a inferior imaging quality in comparison to most central perspective lenses.
The Information Available to a Moving Observer on Shape with Unknown, Isotropic BRDFs.
Chandraker, Manmohan
2016-07-01
Psychophysical studies show motion cues inform about shape even with unknown reflectance. Recent works in computer vision have considered shape recovery for an object of unknown BRDF using light source or object motions. This paper proposes a theory that addresses the remaining problem of determining shape from the (small or differential) motion of the camera, for unknown isotropic BRDFs. Our theory derives a differential stereo relation that relates camera motion to surface depth, which generalizes traditional Lambertian assumptions. Under orthographic projection, we show differential stereo may not determine shape for general BRDFs, but suffices to yield an invariant for several restricted (still unknown) BRDFs exhibited by common materials. For the perspective case, we show that differential stereo yields the surface depth for unknown isotropic BRDF and unknown directional lighting, while additional constraints are obtained with restrictions on the BRDF or lighting. The limits imposed by our theory are intrinsic to the shape recovery problem and independent of choice of reconstruction method. We also illustrate trends shared by theories on shape from differential motion of light source, object or camera, to relate the hardness of surface reconstruction to the complexity of imaging setup.
Lytro camera technology: theory, algorithms, performance analysis
NASA Astrophysics Data System (ADS)
Georgiev, Todor; Yu, Zhan; Lumsdaine, Andrew; Goma, Sergio
2013-03-01
The Lytro camera is the first implementation of a plenoptic camera for the consumer market. We consider it a successful example of the miniaturization aided by the increase in computational power characterizing mobile computational photography. The plenoptic camera approach to radiance capture uses a microlens array as an imaging system focused on the focal plane of the main camera lens. This paper analyzes the performance of Lytro camera from a system level perspective, considering the Lytro camera as a black box, and uses our interpretation of Lytro image data saved by the camera. We present our findings based on our interpretation of Lytro camera file structure, image calibration and image rendering; in this context, artifacts and final image resolution are discussed.
FPGA Based Adaptive Rate and Manifold Pattern Projection for Structured Light 3D Camera System †
Lee, Sukhan
2018-01-01
The quality of the captured point cloud and the scanning speed of a structured light 3D camera system depend upon their capability of handling the object surface of a large reflectance variation in the trade-off of the required number of patterns to be projected. In this paper, we propose and implement a flexible embedded framework that is capable of triggering the camera single or multiple times for capturing single or multiple projections within a single camera exposure setting. This allows the 3D camera system to synchronize the camera and projector even for miss-matched frame rates such that the system is capable of projecting different types of patterns for different scan speed applications. This makes the system capturing a high quality of 3D point cloud even for the surface of a large reflectance variation while achieving a high scan speed. The proposed framework is implemented on the Field Programmable Gate Array (FPGA), where the camera trigger is adaptively generated in such a way that the position and the number of triggers are automatically determined according to camera exposure settings. In other words, the projection frequency is adaptive to different scanning applications without altering the architecture. In addition, the proposed framework is unique as it does not require any external memory for storage because pattern pixels are generated in real-time, which minimizes the complexity and size of the application-specific integrated circuit (ASIC) design and implementation. PMID:29642506
Seeing the Light: A Classroom-Sized Pinhole Camera Demonstration for Teaching Vision
ERIC Educational Resources Information Center
Prull, Matthew W.; Banks, William P.
2005-01-01
We describe a classroom-sized pinhole camera demonstration (camera obscura) designed to enhance students' learning of the visual system. The demonstration consists of a suspended rear-projection screen onto which the outside environment projects images through a small hole in a classroom window. Students can observe these images in a darkened…
LEA Detection and Tracking Method for Color-Independent Visual-MIMO
Kim, Jai-Eun; Kim, Ji-Won; Kim, Ki-Doo
2016-01-01
Communication performance in the color-independent visual-multiple input multiple output (visual-MIMO) technique is deteriorated by light emitting array (LEA) detection and tracking errors in the received image because the image sensor included in the camera must be used as the receiver in the visual-MIMO system. In this paper, in order to improve detection reliability, we first set up the color-space-based region of interest (ROI) in which an LEA is likely to be placed, and then use the Harris corner detection method. Next, we use Kalman filtering for robust tracking by predicting the most probable location of the LEA when the relative position between the camera and the LEA varies. In the last step of our proposed method, the perspective projection is used to correct the distorted image, which can improve the symbol decision accuracy. Finally, through numerical simulation, we show the possibility of robust detection and tracking of the LEA, which results in a symbol error rate (SER) performance improvement. PMID:27384563
LEA Detection and Tracking Method for Color-Independent Visual-MIMO.
Kim, Jai-Eun; Kim, Ji-Won; Kim, Ki-Doo
2016-07-02
Communication performance in the color-independent visual-multiple input multiple output (visual-MIMO) technique is deteriorated by light emitting array (LEA) detection and tracking errors in the received image because the image sensor included in the camera must be used as the receiver in the visual-MIMO system. In this paper, in order to improve detection reliability, we first set up the color-space-based region of interest (ROI) in which an LEA is likely to be placed, and then use the Harris corner detection method. Next, we use Kalman filtering for robust tracking by predicting the most probable location of the LEA when the relative position between the camera and the LEA varies. In the last step of our proposed method, the perspective projection is used to correct the distorted image, which can improve the symbol decision accuracy. Finally, through numerical simulation, we show the possibility of robust detection and tracking of the LEA, which results in a symbol error rate (SER) performance improvement.
Infrared engineering for the advancement of science: A UK perspective
NASA Astrophysics Data System (ADS)
Baker, Ian M.
2017-02-01
Leonardo MW (formerly Selex ES) has been developing infrared sensors and cameras for over 62 years at two main sites at Southampton and Basildon. Funding mainly from UK MOD has seen the technology progress from single element PbSe sensors to advanced, high definition, HgCdTe cameras, widely deployed in many fields today. However, in the last 10 years the major challenges and research funding has come from projects within the scientific sphere, particularly: astronomy and space. Low photon flux, high resolution spectroscopy and fast frame rates are the motivation to drive the sensitivity of infrared detectors to the single photon level. These detectors make use of almost noiseless avalanche gain in HgCdTe to achieve the sensitivity and speed of response. Metal Organic Vapour Phase Epitaxy, MOVPE, grown on low-cost GaAs substrates, provides the capability for crucial bandgap engineering to suppress breakdown currents and allow high avalanche gain even in very low background conditions. This paper describes the progress so far and provides a glimpse of the future.
Leveraging traffic and surveillance video cameras for urban traffic.
DOT National Transportation Integrated Search
2014-12-01
The objective of this project was to investigate the use of existing video resources, such as traffic : cameras, police cameras, red light cameras, and security cameras for the long-term, real-time : collection of traffic statistics. An additional ob...
ERIC Educational Resources Information Center
Liu, Rong; Unger, John A.; Scullion, Vicki A.
2014-01-01
Drawing data from an action-oriented research project for integrating digital video cameras into the reading process in pre-college courses, this study proposes using digital video cameras in reading summaries and responses to promote critical thinking and to teach social justice concepts. The digital video research project is founded on…
Creating and Using a Camera Obscura
ERIC Educational Resources Information Center
Quinnell, Justin
2012-01-01
The camera obscura (Latin for "darkened room") is the earliest optical device and goes back over 2500 years. The small pinhole or lens at the front of the room allows light to enter and this is then "projected" onto a screen inside the room. This differs from a camera, which projects its image onto light-sensitive material.…
NASA Technical Reports Server (NTRS)
1992-01-01
This document describes the Advanced Imaging System CCD based camera. The AIS1 camera system was developed at Photometric Ltd. in Tucson, Arizona as part of a Phase 2 SBIR contract No. NAS5-30171 from the NASA/Goddard Space Flight Center in Greenbelt, Maryland. The camera project was undertaken as a part of the Space Telescope Imaging Spectrograph (STIS) project. This document is intended to serve as a complete manual for the use and maintenance of the camera system. All the different parts of the camera hardware and software are discussed and complete schematics and source code listings are provided.
Center for Coastline Security Technology, Year 3
2008-05-01
Polarization control for 3D Imaging with the Sony SRX-R105 Digital Cinema Projectors 3.4 HDMAX Camera and Sony SRX-R105 Projector Configuration for 3D...HDMAX Camera Pair Figure 3.2 Sony SRX-R105 Digital Cinema Projector Figure 3.3 Effect of camera rotation on projected overlay image. Figure 3.4...system that combines a pair of FAU’s HD-MAX video cameras with a pair of Sony SRX-R105 digital cinema projectors for stereo imaging and projection
Preplanning and Evaluating Video Documentaries and Features.
ERIC Educational Resources Information Center
Maynard, Riley
1997-01-01
This article presents a ten-part pre-production outline and post-production evaluation that helps communications students more effectively improve video skills. Examines camera movement and motion, camera angle and perspective, lighting, audio, graphics, backgrounds and color, special effects, editing, transitions, and music. Provides a glossary…
Rapid orthophoto development system.
DOT National Transportation Integrated Search
2013-06-01
The DMC system procured in the project represented state-of-the-art, large-format digital aerial camera systems at the start of : project. DMC is based on the frame camera model, and to achieve large ground coverage with high spatial resolution, the ...
2. Perspective view showing most of east facade including steps ...
2. Perspective view showing most of east facade including steps and door at north end. Camera pointed NW. - Puget Sound Naval Shipyard, Munitions Storage Bunker, Naval Ammunitions Depot, North of Campbell Trail, Bremerton, Kitsap County, WA
3. Perspective view of north end of Bunker 103 showing ...
3. Perspective view of north end of Bunker 103 showing north set of steel doors. Camera pointed NW. - Puget Sound Naval Shipyard, Munitions Storage Bunker, Naval Ammunitions Depot, North of Campbell Trail, Bremerton, Kitsap County, WA
Motion Imagery and Robotics Application Project (MIRA)
NASA Technical Reports Server (NTRS)
Grubbs, Rodney P.
2010-01-01
This viewgraph presentation describes the Motion Imagery and Robotics Application (MIRA) Project. A detailed description of the MIRA camera service software architecture, encoder features, and on-board communications are presented. A description of a candidate camera under development is also shown.
Polarizing aperture stereoscopic cinema camera
NASA Astrophysics Data System (ADS)
Lipton, Lenny
2012-03-01
The art of stereoscopic cinematography has been held back because of the lack of a convenient way to reduce the stereo camera lenses' interaxial to less than the distance between the eyes. This article describes a unified stereoscopic camera and lens design that allows for varying the interaxial separation to small values using a unique electro-optical polarizing aperture design for imaging left and right perspective views onto a large single digital sensor (the size of the standard 35mm frame) with the means to select left and right image information. Even with the added stereoscopic capability the appearance of existing camera bodies will be unaltered.
Polarizing aperture stereoscopic cinema camera
NASA Astrophysics Data System (ADS)
Lipton, Lenny
2012-07-01
The art of stereoscopic cinematography has been held back because of the lack of a convenient way to reduce the stereo camera lenses' interaxial to less than the distance between the eyes. This article describes a unified stereoscopic camera and lens design that allows for varying the interaxial separation to small values using a unique electro-optical polarizing aperture design for imaging left and right perspective views onto a large single digital sensor, the size of the standard 35 mm frame, with the means to select left and right image information. Even with the added stereoscopic capability, the appearance of existing camera bodies will be unaltered.
Cheng, Yufeng; Jin, Shuying; Wang, Mi; Zhu, Ying; Dong, Zhipeng
2017-06-20
The linear array push broom imaging mode is widely used for high resolution optical satellites (HROS). Using double-cameras attached by a high-rigidity support along with push broom imaging is one method to enlarge the field of view while ensuring high resolution. High accuracy image mosaicking is the key factor of the geometrical quality of complete stitched satellite imagery. This paper proposes a high accuracy image mosaicking approach based on the big virtual camera (BVC) in the double-camera system on the GaoFen2 optical remote sensing satellite (GF2). A big virtual camera can be built according to the rigorous imaging model of a single camera; then, each single image strip obtained by each TDI-CCD detector can be re-projected to the virtual detector of the big virtual camera coordinate system using forward-projection and backward-projection to obtain the corresponding single virtual image. After an on-orbit calibration and relative orientation, the complete final virtual image can be obtained by stitching the single virtual images together based on their coordinate information on the big virtual detector image plane. The paper subtly uses the concept of the big virtual camera to obtain a stitched image and the corresponding high accuracy rational function model (RFM) for concurrent post processing. Experiments verified that the proposed method can achieve seamless mosaicking while maintaining the geometric accuracy.
Spirit Beside 'Home Plate,' Sol 1809 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11803 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11803 NASA Mars Exploration Rover Spirit used its navigation camera to take the images assembled into this stereo, 120-degree view southward after a short drive during the 1,809th Martian day, or sol, of Spirit's mission on the surface of Mars (February 3, 2009). By combining images from the left-eye and right-eye sides of the navigation camera, the view appears three-dimensional when viewed through red-blue glasses with the red lens on the left. Spirit had driven about 2.6 meters (8.5 feet) that sol, continuing a clockwise route around a low plateau called 'Home Plate.' In this image, the rocks visible above the rovers' solar panels are on the slope at the northern edge of Home Plate. This view is presented as a cylindrical-perspective projection with geometric seam correction.Opportunity's Surroundings on Sol 1818 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11846 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11846 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,818th Martian day, or sol, of Opportunity's surface mission (March 5, 2009). South is at the center; north at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 80.3 meters (263 feet) southward earlier on that sol. Tracks from the drive recede northward in this view. The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.Opportunity's Surroundings on Sol 1798 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11850 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11850 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo 180-degree view of the rover's surroundings during the 1,798th Martian day, or sol, of Opportunity's surface mission (Feb. 13, 2009). North is on top. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 111 meters (364 feet) southward on the preceding sol. Tracks from that drive recede northward in this view. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.Uncooled infrared sensors: rapid growth and future perspective
NASA Astrophysics Data System (ADS)
Balcerak, Raymond S.
2000-07-01
The uncooled infrared cameras are now available for both the military and commercial markets. The current camera technology incorporates the fruits of many years of development, focusing on the details of pixel design, novel material processing, and low noise read-out electronics. The rapid insertion of cameras into systems is testimony to the successful completion of this 'first phase' of development. In the military market, the first uncooled infrared cameras will be used for weapon sights, driver's viewers and helmet mounted cameras. Major commercial applications include night driving, security, police and fire fighting, and thermography, primarily for preventive maintenance and process control. The technology for the next generation of cameras is even more demanding, but within reach. The paper outlines the technology program planned for the next generation of cameras, and the approaches to further enhance performance, even to the radiation limit of thermal detectors.
The mosaics of Mars: As seen by the Viking Lander cameras
NASA Technical Reports Server (NTRS)
Levinthal, E. C.; Jones, K. L.
1980-01-01
The mosaics and derivative products produced from many individual high resolution images acquired by the Viking Lander Camera Systems are described: A morning and afternoon mosaic for both cameras at the Lander 1 Chryse Planitia site, and a morning, noon, and afternoon camera pair at Utopia Planitia, the Lander 11 site. The derived products include special geometric projections of the mosaic data sets, polar stereographic (donut), stereoscopic, and orthographic. Contour maps and vertical profiles of the topography were overlaid on the mosaics from which they were derived. Sets of stereo pairs were extracted and enlarged from stereoscopic projections of the mosaics.
NASA Astrophysics Data System (ADS)
Ruf, B.; Erdnuess, B.; Weinmann, M.
2017-08-01
With the emergence of small consumer Unmanned Aerial Vehicles (UAVs), the importance and interest of image-based depth estimation and model generation from aerial images has greatly increased in the photogrammetric society. In our work, we focus on algorithms that allow an online image-based dense depth estimation from video sequences, which enables the direct and live structural analysis of the depicted scene. Therefore, we use a multi-view plane-sweep algorithm with a semi-global matching (SGM) optimization which is parallelized for general purpose computation on a GPU (GPGPU), reaching sufficient performance to keep up with the key-frames of input sequences. One important aspect to reach good performance is the way to sample the scene space, creating plane hypotheses. A small step size between consecutive planes, which is needed to reconstruct details in the near vicinity of the camera may lead to ambiguities in distant regions, due to the perspective projection of the camera. Furthermore, an equidistant sampling with a small step size produces a large number of plane hypotheses, leading to high computational effort. To overcome these problems, we present a novel methodology to directly determine the sampling points of plane-sweep algorithms in image space. The use of the perspective invariant cross-ratio allows us to derive the location of the sampling planes directly from the image data. With this, we efficiently sample the scene space, achieving higher sampling density in areas which are close to the camera and a lower density in distant regions. We evaluate our approach on a synthetic benchmark dataset for quantitative evaluation and on a real-image dataset consisting of aerial imagery. The experiments reveal that an inverse sampling achieves equal and better results than a linear sampling, with less sampling points and thus less runtime. Our algorithm allows an online computation of depth maps for subsequences of five frames, provided that the relative poses between all frames are given.
Scene-aware joint global and local homographic video coding
NASA Astrophysics Data System (ADS)
Peng, Xiulian; Xu, Jizheng; Sullivan, Gary J.
2016-09-01
Perspective motion is commonly represented in video content that is captured and compressed for various applications including cloud gaming, vehicle and aerial monitoring, etc. Existing approaches based on an eight-parameter homography motion model cannot deal with this efficiently, either due to low prediction accuracy or excessive bit rate overhead. In this paper, we consider the camera motion model and scene structure in such video content and propose a joint global and local homography motion coding approach for video with perspective motion. The camera motion is estimated by a computer vision approach, and camera intrinsic and extrinsic parameters are globally coded at the frame level. The scene is modeled as piece-wise planes, and three plane parameters are coded at the block level. Fast gradient-based approaches are employed to search for the plane parameters for each block region. In this way, improved prediction accuracy and low bit costs are achieved. Experimental results based on the HEVC test model show that up to 9.1% bit rate savings can be achieved (with equal PSNR quality) on test video content with perspective motion. Test sequences for the example applications showed a bit rate savings ranging from 3.7 to 9.1%.
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.
Laser-Induced-Fluorescence Photogrammetry and Videogrammetry
NASA Technical Reports Server (NTRS)
Danehy, Paul; Jones, Tom; Connell, John; Belvin, Keith; Watson, Kent
2004-01-01
An improved method of dot-projection photogrammetry and an extension of the method to encompass dot-projection videogrammetry overcome some deficiencies of dot-projection photogrammetry as previously practiced. The improved method makes it possible to perform dot-projection photogrammetry or videogrammetry on targets that have previously not been amenable to dot-projection photogrammetry because they do not scatter enough light. Such targets include ones that are transparent, specularly reflective, or dark. In standard dot-projection photogrammetry, multiple beams of white light are projected onto the surface of an object of interest (denoted the target) to form a known pattern of bright dots. The illuminated surface is imaged in one or more cameras oriented at a nonzero angle or angles with respect to a central axis of the illuminating beams. The locations of the dots in the image(s) contain stereoscopic information on the locations of the dots, and, hence, on the location, shape, and orientation of the illuminated surface of the target. The images are digitized and processed to extract this information. Hardware and software to implement standard dot-projection photogrammetry are commercially available. Success in dot-projection photogrammetry depends on achieving sufficient signal-to-noise ratios: that is, it depends on scattering of enough light by the target so that the dots as imaged in the camera(s) stand out clearly against the ambient-illumination component of the image of the target. In one technique used previously to increase the signal-to-noise ratio, the target is illuminated by intense, pulsed laser light and the light entering the camera(s) is band-pass filtered at the laser wavelength. Unfortunately, speckle caused by the coherence of the laser light engenders apparent movement in the projected dots, thereby giving rise to errors in the measurement of the centroids of the dots and corresponding errors in the computed shape and location of the surface of the target. The improved method is denoted laser-induced-fluorescence photogrammetry.
ERIC Educational Resources Information Center
Mahon, April
2009-01-01
In this article, the author describes an exciting project, written for first-graders, wherein students got to put themselves into their art using a camera and just one computer. In this project, students were challenged to invent their own fantasy place where anything could happen. Using the camera, the author took their picture in their chosen…
A position and attitude vision measurement system for wind tunnel slender model
NASA Astrophysics Data System (ADS)
Cheng, Lei; Yang, Yinong; Xue, Bindang; Zhou, Fugen; Bai, Xiangzhi
2014-11-01
A position and attitude vision measurement system for drop test slender model in wind tunnel is designed and developed. The system used two high speed cameras, one is put to the side of the model and another is put to the position where the camera can look up the model. Simple symbols are set on the model. The main idea of the system is based on image matching technique between the 3D-digital model projection image and the image captured by the camera. At first, we evaluate the pitch angles, the roll angles and the position of the centroid of a model through recognizing symbols in the images captured by the side camera. And then, based on the evaluated attitude info, giving a series of yaw angles, a series of projection images of the 3D-digital model are obtained. Finally, these projection images are matched with the image which captured by the looking up camera, and the best match's projection images corresponds to the yaw angle is the very yaw angle of the model. Simulation experiments are conducted and the results show that the maximal error of attitude measurement is less than 0.05°, which can meet the demand of test in wind tunnel.
2004-03-06
The red marks in this image, taken by the Mars Exploration Rover Opportunity's panoramic camera, indicate holes made by the rover's rock abrasion tool, located on its instrument deployment device, or "arm." The lower hole, located on a target called "McKittrick," was made on the 30th martian day, or sol, of Opportunity's journey. The upper hole, located on a target called "Guadalupe" was made on sol 34 of the rover's mission. The mosaic image was taken using a blue filter at the "El Capitan" region of the Meridiani Planum, Mars, rock outcrop. The image, shown in a vertical-perspective map projection, consists of images acquired on sols 27, 29 and 30 of the rover's mission. http://photojournal.jpl.nasa.gov/catalog/PIA05513
German activities in optical space instrumentation
NASA Astrophysics Data System (ADS)
Hartmann, G.
2018-04-01
In the years of space exploration since the mid-sixties, a wide experience in optical space instrumentation has developed in Germany. This experience ranges from large telescopes in the 1 m and larger category with the accompanying focal plane detectors and spectrometers for all regimes of the electromagnetic spectrum (infrared, visible, ultraviolet, x-rays), to miniature cameras for cometary and planetary explorations. The technologies originally developed for space science. are now also utilized in the fields of earth observation and even optical telecommunication. The presentation will cover all these areas, with examples for specific technological or scientific highlights. Special emphasis will be given to the current state-of-the-art instrumentation technologies in scientific institutions and industry, and to the future perspective in approved and planned projects.
The European perspective for LSST
NASA Astrophysics Data System (ADS)
Gangler, Emmanuel
2017-06-01
LSST is a next generation telescope that will produce an unprecedented data flow. The project goal is to deliver data products such as images and catalogs thus enabling scientific analysis for a wide community of users. As a large scale survey, LSST data will be complementary with other facilities in a wide range of scientific domains, including data from ESA or ESO. European countries have invested in LSST since 2007, in the construction of the camera as well as in the computing effort. This latter will be instrumental in designing the next step: how to distribute LSST data to Europe. Astroinformatics challenges for LSST indeed includes not only the analysis of LSST big data, but also the practical efficiency of the data access.
A Picture is Worth a Thousand Words
ERIC Educational Resources Information Center
Davison, Sarah
2009-01-01
Lions, tigers, and bears, oh my! Digital cameras, young inquisitive scientists, give it a try! In this project, students create an open-ended question for investigation, capture and record their observations--data--with digital cameras, and create a digital story to share their findings. The project follows a 5E learning cycle--Engage, Explore,…
Web Camera Use in Developing Biology, Molecular Biology and Biochemistry Laboratories
ERIC Educational Resources Information Center
Ogren, Paul J.; Deibel, Michael; Kelly, Ian; Mulnix, Amy B.; Peck, Charlie
2004-01-01
The use of a network-ready color camera is described which is primarily marketed as a security device and is used for experiments in developmental biology, genetics and biochemistry laboratories and in special student research projects. Acquiring and analyzing project and archiving images is very important in microscopy, electrophoresis and…
Express Yourself: Using Color Schemes, Cameras, and Computers
ERIC Educational Resources Information Center
Lott, Debra
2005-01-01
Self-portraiture is a great project to introduce the study of color schemes and Expressionism. Through this drawing project, students learn about identity, digital cameras, and creative art software. The lesson can be introduced with a study of Edvard Munch and Expressionism. Expressionism was an art movement in which the intensity of the artist's…
A Visual Servoing-Based Method for ProCam Systems Calibration
Berry, Francois; Aider, Omar Ait; Mosnier, Jeremie
2013-01-01
Projector-camera systems are currently used in a wide field of applications, such as 3D reconstruction and augmented reality, and can provide accurate measurements, depending on the configuration and calibration. Frequently, the calibration task is divided into two steps: camera calibration followed by projector calibration. The latter still poses certain problems that are not easy to solve, such as the difficulty in obtaining a set of 2D–3D points to compute the projection matrix between the projector and the world. Existing methods are either not sufficiently accurate or not flexible. We propose an easy and automatic method to calibrate such systems that consists in projecting a calibration pattern and superimposing it automatically on a known printed pattern. The projected pattern is provided by a virtual camera observing a virtual pattern in an OpenGL model. The projector displays what the virtual camera visualizes. Thus, the projected pattern can be controlled and superimposed on the printed one with the aid of visual servoing. Our experimental results compare favorably with those of other methods considering both usability and accuracy. PMID:24084121
1. Perspective view showing most of Bunker 104 with south ...
1. Perspective view showing most of Bunker 104 with south steps in foreground. Remainder of facade (east side) is shown in photo WA-203-C-2. Camera pointed NW. - Puget Sound Naval Shipyard, Munitions Storage Bunker, Naval Ammunitions Depot, South of Campbell Trail, Bremerton, Kitsap County, WA
STS-47 MS Apt with LINHOF camera on JSC's Bldg 1 rooftop during training
NASA Technical Reports Server (NTRS)
1992-01-01
STS-47 Endeavour, Orbiter Vehicle (OV) 105, Mission Specialist (MS) Jerome Apt sets LINHOF camera lens during photography training session conducted on JSC's Project Management Building Bldg 1 rooftop. Using such a high vantage point as this nine-floor facility, Apt was able to become familiar with Earth Observations camera hadware such as the LINHOF camera.
True 3-D View of 'Columbia Hills' from an Angle
NASA Technical Reports Server (NTRS)
2004-01-01
This mosaic of images from NASA's Mars Exploration Rover Spirit shows a panorama of the 'Columbia Hills' without any adjustment for rover tilt. When viewed through 3-D glasses, depth is much more dramatic and easier to see, compared with a tilt-adjusted version. This is because stereo views are created by producing two images, one corresponding to the view from the panoramic camera's left-eye camera, the other corresponding to the view from the panoramic camera's right-eye camera. The brain processes the visual input more accurately when the two images do not have any vertical offset. In this view, the vertical alignment is nearly perfect, but the horizon appears to curve because of the rover's tilt (because the rover was parked on a steep slope, it was tilted approximately 22 degrees to the west-northwest). Spirit took the images for this 360-degree panorama while en route to higher ground in the 'Columbia Hills.' The highest point visible in the hills is 'Husband Hill,' named for space shuttle Columbia Commander Rick Husband. To the right are the rover's tracks through the soil, where it stopped to perform maintenance on its right front wheel in July. In the distance, below the hills, is the floor of Gusev Crater, where Spirit landed Jan. 3, 2004, before traveling more than 3 kilometers (1.8 miles) to reach this point. This vista comprises 188 images taken by Spirit's panoramic camera from its 213th day, or sol, on Mars to its 223rd sol (Aug. 9 to 19, 2004). Team members at NASA's Jet Propulsion Laboratory and Cornell University spent several weeks processing images and producing geometric maps to stitch all the images together in this mosaic. The 360-degree view is presented in a cylindrical-perspective map projection with geometric seam correction.241-AZ-101 Waste Tank Color Video Camera System Shop Acceptance Test Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
WERRY, S.M.
2000-03-23
This report includes shop acceptance test results. The test was performed prior to installation at tank AZ-101. Both the camera system and camera purge system were originally sought and procured as a part of initial waste retrieval project W-151.
Low-complexity camera digital signal imaging for video document projection system
NASA Astrophysics Data System (ADS)
Hsia, Shih-Chang; Tsai, Po-Shien
2011-04-01
We present high-performance and low-complexity algorithms for real-time camera imaging applications. The main functions of the proposed camera digital signal processing (DSP) involve color interpolation, white balance, adaptive binary processing, auto gain control, and edge and color enhancement for video projection systems. A series of simulations demonstrate that the proposed method can achieve good image quality while keeping computation cost and memory requirements low. On the basis of the proposed algorithms, the cost-effective hardware core is developed using Verilog HDL. The prototype chip has been verified with one low-cost programmable device. The real-time camera system can achieve 1270 × 792 resolution with the combination of extra components and can demonstrate each DSP function.
Advanced EVA Suit Camera System Development Project
NASA Technical Reports Server (NTRS)
Mock, Kyla
2016-01-01
The National Aeronautics and Space Administration (NASA) at the Johnson Space Center (JSC) is developing a new extra-vehicular activity (EVA) suit known as the Advanced EVA Z2 Suit. All of the improvements to the EVA Suit provide the opportunity to update the technology of the video imagery. My summer internship project involved improving the video streaming capabilities of the cameras that will be used on the Z2 Suit for data acquisition. To accomplish this, I familiarized myself with the architecture of the camera that is currently being tested to be able to make improvements on the design. Because there is a lot of benefit to saving space, power, and weight on the EVA suit, my job was to use Altium Design to start designing a much smaller and simplified interface board for the camera's microprocessor and external components. This involved checking datasheets of various components and checking signal connections to ensure that this architecture could be used for both the Z2 suit and potentially other future projects. The Orion spacecraft is a specific project that may benefit from this condensed camera interface design. The camera's physical placement on the suit also needed to be determined and tested so that image resolution can be maximized. Many of the options of the camera placement may be tested along with other future suit testing. There are multiple teams that work on different parts of the suit, so the camera's placement could directly affect their research or design. For this reason, a big part of my project was initiating contact with other branches and setting up multiple meetings to learn more about the pros and cons of the potential camera placements we are analyzing. Collaboration with the multiple teams working on the Advanced EVA Z2 Suit is absolutely necessary and these comparisons will be used as further progress is made for the overall suit design. This prototype will not be finished in time for the scheduled Z2 Suit testing, so my time was also spent creating a case for the original interface board that is already being used. This design is being done by use of Creo 2. Due to time constraints, I may not be able to complete the 3-D printing portion of this design, but I was able to use my knowledge of the interface board and Altium Design to help in the task. As a side project, I assisted another intern in selecting and programming a microprocessor to control linear actuators. These linear actuators will be used to move various increments of polyethylene for controlled radiation testing. For this, we began the software portion of the project using the Arduino's coding environment to control an Arduino Due and H-Bridge components. Along with the obvious learning of computer programs such as Altium Design and Creo 2, I also acquired more skills with networking and collaborating with others, being able to multi-task because of responsibilities to work on various projects, and how to set realistic goals in the work place. Like many internship projects, this project will be continued and improved, so I also had the chance to improve my organization and communication skills as I documented all of my meetings and research. As a result of my internship at JSC, I desire to continue a career with NASA, whether that be through another internship or possibly a co-op. I am excited to return to my university and continue my education in electrical engineering because of all of my experiences at JSC.
Heterogeneous Vision Data Fusion for Independently Moving Cameras
2010-03-01
target detection , tracking , and identification over a large terrain. The goal of the project is to investigate and evaluate the existing image...fusion algorithms, develop new real-time algorithms for Category-II image fusion, and apply these algorithms in moving target detection and tracking . The...moving target detection and classification. 15. SUBJECT TERMS Image Fusion, Target Detection , Moving Cameras, IR Camera, EO Camera 16. SECURITY
Video Capture of Perforator Flap Harvesting Procedure with a Full High-definition Wearable Camera
2016-01-01
Summary: Recent advances in wearable recording technology have enabled high-quality video recording of several surgical procedures from the surgeon’s perspective. However, the available wearable cameras are not optimal for recording the harvesting of perforator flaps because they are too heavy and cannot be attached to the surgical loupe. The Ecous is a small high-resolution camera that was specially developed for recording loupe magnification surgery. This study investigated the use of the Ecous for recording perforator flap harvesting procedures. The Ecous SC MiCron is a high-resolution camera that can be mounted directly on the surgical loupe. The camera is light (30 g) and measures only 28 × 32 × 60 mm. We recorded 23 perforator flap harvesting procedures with the Ecous connected to a laptop through a USB cable. The elevated flaps included 9 deep inferior epigastric artery perforator flaps, 7 thoracodorsal artery perforator flaps, 4 anterolateral thigh flaps, and 3 superficial inferior epigastric artery flaps. All procedures were recorded with no equipment failure. The Ecous recorded the technical details of the perforator dissection at a high-resolution level. The surgeon did not feel any extra stress or interference when wearing the Ecous. The Ecous is an ideal camera for recording perforator flap harvesting procedures. It fits onto the surgical loupe perfectly without creating additional stress on the surgeon. High-quality video from the surgeon’s perspective makes accurate documentation of the procedures possible, thereby enhancing surgical education and allowing critical self-reflection. PMID:27482504
Active learning in camera calibration through vision measurement application
NASA Astrophysics Data System (ADS)
Li, Xiaoqin; Guo, Jierong; Wang, Xianchun; Liu, Changqing; Cao, Binfang
2017-08-01
Since cameras are increasingly more used in scientific application as well as in the applications requiring precise visual information, effective calibration of such cameras is getting more important. There are many reasons why the measurements of objects are not accurate. The largest reason is that the lens has a distortion. Another detrimental influence on the evaluation accuracy is caused by the perspective distortions in the image. They happen whenever we cannot mount the camera perpendicularly to the objects we want to measure. In overall, it is very important for students to understand how to correct lens distortions, that is camera calibration. If the camera is calibrated, the images are rectificated, and then it is possible to obtain undistorted measurements in world coordinates. This paper presents how the students should develop a sense of active learning for mathematical camera model besides the theoretical scientific basics. The authors will present the theoretical and practical lectures which have the goal of deepening the students understanding of the mathematical models of area scan cameras and building some practical vision measurement process by themselves.
Altered Perspectives: Immersive Environments
NASA Astrophysics Data System (ADS)
Shipman, J. S.; Webley, P. W.
2016-12-01
Immersive environments provide an exciting experiential technology to visualize the natural world. Given the increasing accessibility of 360o cameras and virtual reality headsets we are now able to visualize artistic principles and scientific concepts in a fully immersive environment. The technology has become popular for photographers as well as designers, industry, educational groups, and museums. Here we show a sci-art perspective on the use of optics and light in the capture and manipulation of 360o images and video of geologic phenomena and cultural heritage sites in Alaska, England, and France. Additionally, we will generate intentionally altered perspectives to lend a surrealistic quality to the landscapes. Locations include the Catacombs of Paris, the Palace of Versailles, and the Northern Lights over Fairbanks, Alaska. Some 360o view cameras now use small portable dual lens technology extending beyond the 180o fish eye lens previously used, providing better coverage and image quality. Virtual reality headsets range in level of sophistication and cost, with the most affordable versions using smart phones and Google Cardboard viewers. The equipment used in this presentation includes a Ricoh Theta S spherical imaging camera. Here we will demonstrate the use of 360o imaging with attendees being able to be part of the immersive environment and experience our locations as if they were visiting themselves.
Opportunity's Surroundings After Sol 1820 Drive (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11841 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11841 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this full-circle view of the rover's surroundings during the 1,820th to 1,822nd Martian days, or sols, of Opportunity's surface mission (March 7 to 9, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 20.6 meters toward the northwest on Sol 1820 before beginning to take the frames in this view. Tracks from that drive recede southwestward. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). The terrain in this portion of Mars' Meridiani Planum region includes dark-toned sand ripples and small exposures of lighter-toned bedrock. This view is presented as a cylindrical-perspective projection with geometric seam correction.Dust Devil in Spirit's View Ahead on Sol 1854 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11960 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11960 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,854th Martian day, or sol, of Spirit's surface mission (March 21, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 13.79 meters (45 feet) westward earlier on Sol 1854. West is at the center, where a dust devil is visible in the distance. North on the right, where Husband Hill dominates the horizon; Spirit was on top of Husband Hill in September and October 2005. South is on the left, where lighter-toned rock lines the edge of the low plateau called 'Home Plate.' This view is presented as a cylindrical-perspective projection with geometric seam correction.Camera Ready: Capturing a Digital History of Chester
ERIC Educational Resources Information Center
Lehman, Kathy
2008-01-01
Armed with digital cameras, voice recorders, and movie cameras, students from Thomas Dale High School in Chester, Virginia, have been exploring neighborhoods, interviewing residents, and collecting memories of their hometown. In this article, the author describes "Digital History of Chester", a project for creating a commemorative DVD.…
On the Complexity of Digital Video Cameras in/as Research: Perspectives and Agencements
ERIC Educational Resources Information Center
Bangou, Francis
2014-01-01
The goal of this article is to consider the potential for digital video cameras to produce as part of a research agencement. Our reflection will be guided by the current literature on the use of video recordings in research, as well as by the rhizoanalysis of two vignettes. The first of these vignettes is associated with a short video clip shot by…
ERIC Educational Resources Information Center
Green, Carie
2016-01-01
This article explores the use of wearable cameras with children as a data collection means to engage young children as active researchers in recording their experiences in natural environments. This method captures children's unique perspectives of being-in-the-world, depicting what they see, hear, say, touch, and their interactions with others.…
SR-71 Ship #1 - Ultraviolet Experiment
NASA Technical Reports Server (NTRS)
1994-01-01
NASA's SR-71 streaks into the twilight on a night/science flight from the Dryden Flight Research Center, Edwards, California. Mounted in the nose of the SR-71 was an ultraviolet video camera aimed skyward to capture images of stars, asteroids and comets. The science portion of the flight is a project of the Jet Propulsion Laboratory, Pasadena, California. Two SR-71 aircraft have been used by NASA as test beds for high-speed and high-altitude aeronautical research. One early research project flown on one of Dryden's SR-71s consisted of a proposal for a series of flights using the SR-71 as a science camera platform for the Jet Propulsion Laboratory (JPL) of the California Institute of Technology, which operates under contract to NASA in much the way that NASA centers do. In March 1993, an upward-looking ultraviolet (UV) video camera placed in the SR-71's nosebay studied a variety of celestial objects in the ultraviolet light spectrum. The SR-71 was proposed as a test bed for the experiment because it is capable of flying at altitudes above 80,000 feet for an extended length of time. Observation of ultraviolet radiation is not possible from the Earth's surface because the atmosphere's ozone layer absorbs UV rays. Study of UV radiation is important because it is known to cause skin cancer with prolonged exposure. UV radiation is also valuable to study from an astronomical perspective. Satellite study of ultraviolet radiation is very expensive. As a result, the South West Research Institute (SWRI) in Texas developed the hypothesis of using a high-flying aircraft such as the SR-71 to conduct UV observations. The SR-71 is capable of flying above 90 percent of the Earth's atmosphere. The flight program was also designed to test the stability of the aircraft as a test bed for UV observation. A joint flight program was developed between the JPL and NASA's Ames-Dryden Flight Research Facility (redesignated the Dryden Flight Research Center, Edwards, California, in 1994) in conjunction with SWRI to test the hypothesis. Dryden modified the nosebay of the SR-71, creating an upward-observing window to carry SWRI's ultraviolet CCD camera so it could make observations. According to Dryden's SR-71 Project Manager Dave Lux, a single flight of the aircraft confirmed the aircraft's capability and stability as a test bed for UV observations. SWRI's principle investigator was Dr. Allen Stern.
Perspectives Do Matter: "Joint Screen", a Promising Methodology for Multimodal Interaction Analysis
ERIC Educational Resources Information Center
Arend, Béatrice; Sunnen, Patrick; Fixmer, Pierre; Sujbert, Monika
2014-01-01
This paper discusses theoretical and methodological issues arising from a video-based research design and the emergent tool "Joint Screen'"when grasping joint activity. We share our reflections regarding the combined reading of four synchronised camera perspectives combined in one screen. By these means we reconstruct and analyse…
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.
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.
NASA Astrophysics Data System (ADS)
Reulke, R.; Baltrusch, S.; Brunn, A.; Komp, K.; Kresse, W.; von Schönermark, M.; Spreckels, V.
2012-08-01
10 years after the first introduction of a digital airborne mapping camera in the ISPRS conference 2000 in Amsterdam, several digital cameras are now available. They are well established in the market and have replaced the analogue camera. A general improvement in image quality accompanied the digital camera development. The signal-to-noise ratio and the dynamic range are significantly better than with the analogue cameras. In addition, digital cameras can be spectrally and radiometrically calibrated. The use of these cameras required a rethinking in many places though. New data products were introduced. In the recent years, some activities took place that should lead to a better understanding of the cameras and the data produced by these cameras. Several projects, like the projects of the German Society for Photogrammetry, Remote Sensing and Geoinformation (DGPF) or EuroSDR (European Spatial Data Research), were conducted to test and compare the performance of the different cameras. In this paper the current DIN (Deutsches Institut fuer Normung - German Institute for Standardization) standards will be presented. These include the standard for digital cameras, the standard for ortho rectification, the standard for classification, and the standard for pan-sharpening. In addition, standards for the derivation of elevation models, the use of Radar / SAR, and image quality are in preparation. The OGC has indicated its interest in participating that development. The OGC has already published specifications in the field of photogrammetry and remote sensing. One goal of joint future work could be to merge these formerly independent developments and the joint development of a suite of implementation specifications for photogrammetry and remote sensing.
Measuring fire behavior with photography
Hubert B. Clements; Darold E. Ward; Carl W. Adkins
1983-01-01
Photography is practical for recording and measuring some aspects of forest fire behavior if the scale and perspective can be determined. This paper describes a photogrammetric method for measuring flame height and rate of spread for fires on flat terrain. The flames are photographed at known times with a camera in front of the advancing fire. Scale and perspective of...
Optical Transient Monitor (OTM) for BOOTES Project
NASA Astrophysics Data System (ADS)
Páta, P.; Bernas, M.; Castro-Tirado, A. J.; Hudec, R.
2003-04-01
The Optical Transient Monitor (OTM) is a software for control of three wide and ultra-wide filed cameras of BOOTES (Burst Observer and Optical Transient Exploring System) station. The OTM is a PC based and it is powerful tool for taking images from two SBIG CCD cameras in same time or from one camera only. The control program for BOOTES cameras is Windows 98 or MSDOS based. Now the version for Windows 2000 is prepared. There are five main supported modes of work. The OTM program could control cameras and evaluate image data without human interaction.
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.
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.
The hands of the projectionist.
Cartwright, Lisa
2011-09-01
This essay considers the work of projection and the hand of the projectionist as important components of the social space of the cinema as it comes into being in the nineteenth century and the early decades of the twentieth. I bring the concept ofMaurice Merleau-Ponty on the place of the body as an entity that applies itself to the world "like a hand to an instrument" into a discussion of the pre-cinematic projector as an instrument that we can interpret as evidence of the experience of the work of the projectionist in the spirit of film theory and media archaeology, moving work on instrumentation in a different direction from the analysis of the work of the black box in laboratory studies. Projection is described as a psychological as well as a mechanical process. It is suggested that we interpret the projector not simply in its activity as it projects films, but in its movement from site to site and in the workings of the hand of its operator behind the scenes. This account suggests a different perspective on the cinematic turn of the nineteenth century, a concept typically approached through the study of the image, the look, the camera, and the screen.
NASA Astrophysics Data System (ADS)
Chen, Chao; Gao, Nan; Wang, Xiangjun; Zhang, Zonghua
2018-05-01
Three-dimensional (3D) shape measurement based on fringe pattern projection techniques has been commonly used in various fields. One of the remaining challenges in fringe pattern projection is that camera sensor saturation may occur if there is a large range of reflectivity variation across the surface that causes measurement errors. To overcome this problem, a novel fringe pattern projection method is proposed to avoid image saturation and maintain high-intensity modulation for measuring shiny surfaces by adaptively adjusting the pixel-to-pixel projection intensity according to the surface reflectivity. First, three sets of orthogonal color fringe patterns and a sequence of uniform gray-level patterns with different gray levels are projected onto a measured surface by a projector. The patterns are deformed with respect to the object surface and captured by a camera from a different viewpoint. Subsequently, the optimal projection intensity at each pixel is determined by fusing different gray levels and transforming the camera pixel coordinate system into the projector pixel coordinate system. Finally, the adapted fringe patterns are created and used for 3D shape measurement. Experimental results on a flat checkerboard and shiny objects demonstrate that the proposed method can measure shiny surfaces with high accuracy.
3D Rainbow Particle Tracking Velocimetry
NASA Astrophysics Data System (ADS)
Aguirre-Pablo, Andres A.; Xiong, Jinhui; Idoughi, Ramzi; Aljedaani, Abdulrahman B.; Dun, Xiong; Fu, Qiang; Thoroddsen, Sigurdur T.; Heidrich, Wolfgang
2017-11-01
A single color camera is used to reconstruct a 3D-3C velocity flow field. The camera is used to record the 2D (X,Y) position and colored scattered light intensity (Z) from white polyethylene tracer particles in a flow. The main advantage of using a color camera is the capability of combining different intensity levels for each color channel to obtain more depth levels. The illumination system consists of an LCD projector placed perpendicularly to the camera. Different intensity colored level gradients are projected onto the particles to encode the depth position (Z) information of each particle, benefiting from the possibility of varying the color profiles and projected frequencies up to 60 Hz. Chromatic aberrations and distortions are estimated and corrected using a 3D laser engraved calibration target. The camera-projector system characterization is presented considering size and depth position of the particles. The use of these components reduces dramatically the cost and complexity of traditional 3D-PTV systems.
Metric Calibration of a Focused Plenoptic Camera Based on a 3d Calibration Target
NASA Astrophysics Data System (ADS)
Zeller, N.; Noury, C. A.; Quint, F.; Teulière, C.; Stilla, U.; Dhome, M.
2016-06-01
In this paper we present a new calibration approach for focused plenoptic cameras. We derive a new mathematical projection model of a focused plenoptic camera which considers lateral as well as depth distortion. Therefore, we derive a new depth distortion model directly from the theory of depth estimation in a focused plenoptic camera. In total the model consists of five intrinsic parameters, the parameters for radial and tangential distortion in the image plane and two new depth distortion parameters. In the proposed calibration we perform a complete bundle adjustment based on a 3D calibration target. The residual of our optimization approach is three dimensional, where the depth residual is defined by a scaled version of the inverse virtual depth difference and thus conforms well to the measured data. Our method is evaluated based on different camera setups and shows good accuracy. For a better characterization of our approach we evaluate the accuracy of virtual image points projected back to 3D space.
STS-99 Commander Kregel poses with EARTHKAM camera on OV-105's flight deck
2000-03-30
STS099-314-035 (11-22 February 2000) ---Astronaut Kevin R. Kregel, mission commander, works with camera equipment, which was used for the EarthKAM project. The camera stayed busy throughout the 11-day mission taking vertical imagery of the Earth points of opportunity for the project. Students across the United States and in France, Germany and Japan took photos throughout the STS-99 mission. And they are using these new photos, plus all the images already available in the EarthKAM system, to enhance their classroom learning in Earth and space science, social studies, geography, mathematics and more.
Emission computerized axial tomography from multiple gamma-camera views using frequency filtering.
Pelletier, J L; Milan, C; Touzery, C; Coitoux, P; Gailliard, P; Budinger, T F
1980-01-01
Emission computerized axial tomography is achievable in any nuclear medicine department from multiple gamma camera views. Data are collected by rotating the patient in front of the camera. A simple fast algorithm is implemented, known as the convolution technique: first the projection data are Fourier transformed and then an original filter designed for optimizing resolution and noise suppression is applied; finally the inverse transform of the latter operation is back-projected. This program, which can also take into account the attenuation for single photon events, was executed with good results on phantoms and patients. We think that it can be easily implemented for specific diagnostic problems.
Examining wildlife responses to phenology and wildfire using a landscape-scale camera trap network
Miguel L. Villarreal; Leila Gass; Laura Norman; Joel B. Sankey; Cynthia S. A. Wallace; Dennis McMacken; Jack L. Childs; Roy Petrakis
2013-01-01
Between 2001 and 2009, the Borderlands Jaguar Detection Project deployed 174 camera traps in the mountains of southern Arizona to record jaguar activity. In addition to jaguars, the motion-activated cameras, placed along known wildlife travel routes, recorded occurrences of ~ 20 other animal species. We examined temporal relationships of white-tailed deer (Odocoileus...
Reticle stage based linear dosimeter
Berger, Kurt W [Livermore, CA
2007-03-27
A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.
Reticle stage based linear dosimeter
Berger, Kurt W.
2005-06-14
A detector to measure EUV intensity employs a linear array of photodiodes. The detector is particularly suited for photolithography systems that includes: (i) a ringfield camera; (ii) a source of radiation; (iii) a condenser for processing radiation from the source of radiation to produce a ringfield illumination field for illuminating a mask; (iv) a reticle that is positioned at the ringfield camera's object plane and from which a reticle image in the form of an intensity profile is reflected into the entrance pupil of the ringfield camera, wherein the reticle moves in a direction that is transverse to the length of the ringfield illumination field that illuminates the reticle; (v) detector for measuring the entire intensity along the length of the ringfield illumination field that is projected onto the reticle; and (vi) a wafer onto which the reticle imaged is projected from the ringfield camera.
Current status of Polish Fireball Network
NASA Astrophysics Data System (ADS)
Wiśniewski, M.; Żołądek, P.; Olech, A.; Tyminski, Z.; Maciejewski, M.; Fietkiewicz, K.; Rudawska, R.; Gozdalski, M.; Gawroński, M. P.; Suchodolski, T.; Myszkiewicz, M.; Stolarz, M.; Polakowski, K.
2017-09-01
The Polish Fireball Network (PFN) is a project to monitor regularly the sky over Poland in order to detect bright fireballs. In 2016 the PFN consisted of 36 continuously active stations with 57 sensitive analogue video cameras and 7 high resolution digital cameras. In our observations we also use spectroscopic and radio techniques. A PyFN software package for trajectory and orbit determination was developed. The PFN project is an example of successful participation of amateur astronomers who can provide valuable scientific data. The network is coordinated by astronomers from Copernicus Astronomical Centre in Warsaw, Poland. In 2011-2015 the PFN cameras recorded 214,936 meteor events. Using the PFN data and the UFOOrbit software 34,609 trajectories and orbits were calculated. In the following years we are planning intensive modernization of the PFN network including installation of dozens of new digital cameras.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu Feipeng; Shi Hongjian; Bai Pengxiang
In fringe projection, the CCD camera and the projector are often placed at equal height. In this paper, we will study the calibration of an unequal arrangement of the CCD camera and the projector. The principle of fringe projection with two-dimensional digital image correlation to acquire the profile of object surface is described in detail. By formula derivation and experiment, the linear relationship between the out-of-plane calibration coefficient and the y coordinate is clearly found. To acquire the three-dimensional (3D) information of an object correctly, this paper presents an effective calibration method with linear least-squares fitting, which is very simplemore » in principle and calibration. Experiments are implemented to validate the availability and reliability of the calibration method.« less
Uav Cameras: Overview and Geometric Calibration Benchmark
NASA Astrophysics Data System (ADS)
Cramer, M.; Przybilla, H.-J.; Zurhorst, A.
2017-08-01
Different UAV platforms and sensors are used in mapping already, many of them equipped with (sometimes) modified cameras as known from the consumer market. Even though these systems normally fulfil their requested mapping accuracy, the question arises, which system performs best? This asks for a benchmark, to check selected UAV based camera systems in well-defined, reproducible environments. Such benchmark is tried within this work here. Nine different cameras used on UAV platforms, representing typical camera classes, are considered. The focus is laid on the geometry here, which is tightly linked to the process of geometrical calibration of the system. In most applications the calibration is performed in-situ, i.e. calibration parameters are obtained as part of the project data itself. This is often motivated because consumer cameras do not keep constant geometry, thus, cannot be seen as metric cameras. Still, some of the commercial systems are quite stable over time, as it was proven from repeated (terrestrial) calibrations runs. Already (pre-)calibrated systems may offer advantages, especially when the block geometry of the project does not allow for a stable and sufficient in-situ calibration. Especially for such scenario close to metric UAV cameras may have advantages. Empirical airborne test flights in a calibration field have shown how block geometry influences the estimated calibration parameters and how consistent the parameters from lab calibration can be reproduced.
DSLR Double Star Astrometry Using an Alt-Az Telescope
NASA Astrophysics Data System (ADS)
Frey, Thomas; Haworth, David
2014-07-01
The goal of this project was to determine if the double star's angular separation and position angle measurements could be successfully measured with a motor driven, alt-azimuth Dobsonian-mounted Newtonian telescope (without a field rotator), and a digital single-lens reflex (DSLR) camera. Additionally, the project was constrained by using as much existing equipment as much as possible, including an Apple MacBook Pro laptop and a Canon T2i camera. This project was additionally challenging because the first author had no experience with astrophotography.
Ecological Forecasting Project Management with Examples
NASA Technical Reports Server (NTRS)
Skiles, J. W.; Schmidt, Cindy; Estes, Maury; Turner, Woody
2017-01-01
Once scientists publish results of their projects and studies, all too often they end up on the shelf and are not otherwise used. The NASA Earth Science Division established its Applied Sciences Program (ASP) to apply research findings to help solve and manage real-world problems and needs. ASP-funded projects generally produce decision support systems for operational applications which are expected to last beyond the end of the NASA funding. Because of NASAs unique perspective of looking down on the Earth from space, ASP studies involve the use of remotely sensed information consisting of satellite data and imagery as well as information from sub-orbital platforms. ASP regularly solicits Earth science proposals that address one or more focus areas; disasters mitigation, ecological forecasting, health and air quality, and water resources. Reporting requirements for ASP-funded projects are different from those typical for research grants from NASA and other granting agencies, requiring management approaches different from other programs. This presentation will address the foregoing in some detail and give examples of three ASP-funded ecological forecasting projects that include: 1) the detection and survey of chimpanzee habitat in Africa from space, 2) harmful algal blooms (HABs) in the California Current System affecting aquaculture facilities and marine mammal populations, and 3) a call for the public to identify North America wildlife in Wisconsin using trail camera photos. Contact information to propose to ASP solicitations for those PIs interested is also provided.
ERIC Educational Resources Information Center
Ingram, Leigh-Anne
2014-01-01
Often girls are the objects of the camera's lens and subjects of the researcher's gaze. This article describes a qualitative study using a collaborative, creative and critical methodology to explore girls' perspectives on gender, citizenship and schooling. The seven adolescent girl participants used Photovoice to engage with their roles as…
Sweatt, William C.
1998-01-01
A projection lithography camera is presented with a wide ringfield optimized so as to make efficient use of extreme ultraviolet radiation from a large area radiation source (e.g., D.sub.source .apprxeq.0.5 mm). The camera comprises four aspheric mirrors optically arranged on a common axis of symmetry with an increased etendue for the camera system. The camera includes an aperture stop that is accessible through a plurality of partial aperture stops to synthesize the theoretical aperture stop. Radiation from a mask is focused to form a reduced image on a wafer, relative to the mask, by reflection from the four aspheric mirrors.
STS-52 MS Shepherd during camera equipment training on JSC's Bldg 1 rooftop
NASA Technical Reports Server (NTRS)
1992-01-01
STS-52 Columbia, Orbiter Vehicle (OV) 102, Mission Specialist (MS) William M. Shepherd aims a 35mm camera at a distant subject from his vantage point atop the roof of JSC's nine-story Project Management Building Bldg 1. The training session familiarized Shepherd with camera equipment to be used in Earth observation documentation during STS-52.
NASA Technical Reports Server (NTRS)
Ansar, Adnan I.; Brennan, Shane; Clouse, Daniel S.
2012-01-01
As imagery is collected from an airborne platform, an individual viewing the images wants to know from where on the Earth the images were collected. To do this, some information about the camera needs to be known, such as its position and orientation relative to the Earth. This can be provided by common inertial navigation systems (INS). Once the location of the camera is known, it is useful to project an image onto some representation of the Earth. Due to the non-smooth terrain of the Earth (mountains, valleys, etc.), this projection is highly non-linear. Thus, to ensure accurate projection, one needs to project onto a digital elevation map (DEM). This allows one to view the images overlaid onto a representation of the Earth. A code has been developed that takes an image, a model of the camera used to acquire that image, the pose of the camera during acquisition (as provided by an INS), and a DEM, and outputs an image that has been geo-rectified. The world coordinate of the bounds of the image are provided for viewing purposes. The code finds a mapping from points on the ground (DEM) to pixels in the image. By performing this process for all points on the ground, one can "paint" the ground with the image, effectively performing a projection of the image onto the ground. In order to make this process efficient, a method was developed for finding a region of interest (ROI) on the ground to where the image will project. This code is useful in any scenario involving an aerial imaging platform that moves and rotates over time. Many other applications are possible in processing aerial and satellite imagery.
Reasoning About Visibility in Mirrors: A Comparison Between a Human Observer and a Camera.
Bertamini, Marco; Soranzo, Alessandro
2018-01-01
Human observers make errors when predicting what is visible in a mirror. This is true for perception with real mirrors as well as for reasoning about mirrors shown in diagrams. We created an illustration of a room, a top-down view, with a mirror on a wall and objects (nails) on the opposite wall. The task was to select which nails were visible in the mirror from a given position (viewpoint). To study the importance of the social nature of the viewpoint, we divided the sample ( N = 108) in two groups. One group ( n = 54) were tested with a scene in which there was the image of a person. The other group ( n = 54) were tested with the same scene but with a camera replacing the person. Participants were instructed to think about what would be captured by a camera on a tripod. This manipulation tests the effect of social perspective-taking in reasoning about mirrors. As predicted, performance on the task shows an overestimation of what can be seen in a mirror and a bias to underestimate the role of the different viewpoints, that is, a tendency to treat the mirror as if it captures information independently of viewpoint. In terms of the comparison between person and camera, there were more errors for the camera, suggesting an advantage for evaluating a human viewpoint as opposed to an artificial viewpoint. We suggest that social mechanisms may be involved in perspective-taking in reasoning rather than in automatic attention allocation.
Lens and Camera Arrays for Sky Surveys and Space Surveillance
NASA Astrophysics Data System (ADS)
Ackermann, M.; Cox, D.; McGraw, J.; Zimmer, P.
2016-09-01
In recent years, a number of sky survey projects have chosen to use arrays of commercial cameras coupled with commercial photographic lenses to enable low-cost, wide-area observation. Projects such as SuperWASP, FAVOR, RAPTOR, Lotis, PANOPTES, and DragonFly rely on multiple cameras with commercial lenses to image wide areas of the sky each night. The sensors are usually commercial astronomical charge coupled devices (CCDs) or digital single reflex (DSLR) cameras, while the lenses are large-aperture, highend consumer items intended for general photography. While much of this equipment is very capable and relatively inexpensive, this approach comes with a number of significant limitations that reduce sensitivity and overall utility of the image data. The most frequently encountered limitations include lens vignetting, narrow spectral bandpass, and a relatively large point spread function. Understanding these limits helps to assess the utility of the data, and identify areas where advanced optical designs could significantly improve survey performance.
NASA Technical Reports Server (NTRS)
Watson, Dan M.
1997-01-01
Under the terms of our contract with NASA Ames Research Center, the University of Rochester (UR) offers the following final technical report on grant NAG 2-958, Molecular shocks associated with massive young stars: CO line images with a new far-infrared spectroscopic camera, given for implementation of the UR Far-Infrared Spectroscopic Camera (FISC) on the Kuiper Airborne Observatory (KAO), and use of this camera for observations of star-formation regions 1. Two KAO flights in FY 1995, the final year of KAO operations, were awarded to this program, conditional upon a technical readiness confirmation which was given in January 1995. The funding period covered in this report is 1 October 1994 - 30 September 1996. The project was supported with $30,000, and no funds remained at the conclusion of the project.
Along Endurance Crater's Inner Wall (Left Eye)
NASA Technical Reports Server (NTRS)
2004-01-01
This view from the base of 'Burns Cliff' in the inner wall of 'Endurance Crater' combines several frames taken by Opportunity's navigation camera during the NASA rover's 280th martian day (Nov. 6, 2004). It is the left-eye member of a stereo pair, presented in a cylindrical-perspective projection with geometric seam correction. The cliff dominates the left and right portions of the image, while the central portion looks down into the crater. The 'U' shape of this mosaic results from the rover's tilt of about 30 degrees on the sloped ground below the cliff. Rover wheel tracks in the left half of the image show some of the slippage the rover experienced in making its way to this point. The site from which this image was taken has been designated as Opportunity's Site 37.NASA Technical Reports Server (NTRS)
2004-01-01
[figure removed for brevity, see original site] Figure 1 [figure removed for brevity, see original site] Figure 2 This navigation camera mosaic, created from images taken by NASA's Mars Exploration Rover Opportunity on sols 115 and 116 (May 21 and 22, 2004) provides a dramatic view of 'Endurance Crater.' The rover engineering team carefully plotted the safest path into the football field-sized crater, eventually easing the rover down the slopes around sol 130 (June 12, 2004). To the upper left of the crater sits the rover's protective heatshield, which sheltered Opportunity as it passed through the martian atmosphere. The 360-degree, stereo view is presented in a cylindrical-perspective projection, with geometric and radiometric seam correction. Figure 1 is the left-eye view of a stereo pair and Figure 2 is the right-eye view of a stereo pair.NASA Technical Reports Server (NTRS)
Nabors, Sammy
2015-01-01
NASA offers companies an optical system that provides a unique panoramic perspective with a single camera. NASA's Marshall Space Flight Center has developed a technology that combines a panoramic refracting optic (PRO) lens with a unique detection system to acquire a true 360-degree field of view. Although current imaging systems can acquire panoramic images, they must use up to five cameras to obtain the full field of view. MSFC's technology obtains its panoramic images from one vantage point.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lemaire, H.; Barat, E.; Carrel, F.
In this work, we tested Maximum likelihood expectation-maximization (MLEM) algorithms optimized for gamma imaging applications on two recent coded mask gamma cameras. We respectively took advantage of the characteristics of the GAMPIX and Caliste HD-based gamma cameras: noise reduction thanks to mask/anti-mask procedure but limited energy resolution for GAMPIX, high energy resolution for Caliste HD. One of our short-term perspectives is the test of MAPEM algorithms integrating specific prior values for the data to reconstruct adapted to the gamma imaging topic. (authors)
Repurposing video recordings for structure motion estimations
NASA Astrophysics Data System (ADS)
Khaloo, Ali; Lattanzi, David
2016-04-01
Video monitoring of public spaces is becoming increasingly ubiquitous, particularly near essential structures and facilities. During any hazard event that dynamically excites a structure, such as an earthquake or hurricane, proximal video cameras may inadvertently capture the motion time-history of the structure during the event. If this dynamic time-history could be extracted from the repurposed video recording it would become a valuable forensic analysis tool for engineers performing post-disaster structural evaluations. The difficulty is that almost all potential video cameras are not installed to monitor structure motions, leading to camera perspective distortions and other associated challenges. This paper presents a method for extracting structure motions from videos using a combination of computer vision techniques. Images from a video recording are first reprojected into synthetic images that eliminate perspective distortion, using as-built knowledge of a structure for calibration. The motion of the camera itself during an event is also considered. Optical flow, a technique for tracking per-pixel motion, is then applied to these synthetic images to estimate the building motion. The developed method was validated using the experimental records of the NEESHub earthquake database. The results indicate that the technique is capable of estimating structural motions, particularly the frequency content of the response. Further work will evaluate variants and alternatives to the optical flow algorithm, as well as study the impact of video encoding artifacts on motion estimates.
NASA Astrophysics Data System (ADS)
Conforti, Vito; Trifoglio, Massimo; Bulgarelli, Andrea; Gianotti, Fulvio; Fioretti, Valentina; Tacchini, Alessandro; Zoli, Andrea; Malaguti, Giuseppe; Capalbi, Milvia; Catalano, Osvaldo
2014-07-01
ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) is a Flagship Project financed by the Italian Ministry of Education, University and Research, and led by INAF, the Italian National Institute of Astrophysics. Within this framework, INAF is currently developing an end-to-end prototype of a Small Size dual-mirror Telescope. In a second phase the ASTRI project foresees the installation of the first elements of the array at CTA southern site, a mini-array of 7 telescopes. The ASTRI Camera DAQ Software is aimed at the Camera data acquisition, storage and display during Camera development as well as during commissioning and operations on the ASTRI SST-2M telescope prototype that will operate at the INAF observing station located at Serra La Nave on the Mount Etna (Sicily). The Camera DAQ configuration and operations will be sequenced either through local operator commands or through remote commands received from the Instrument Controller System that commands and controls the Camera. The Camera DAQ software will acquire data packets through a direct one-way socket connection with the Camera Back End Electronics. In near real time, the data will be stored in both raw and FITS format. The DAQ Quick Look component will allow the operator to display in near real time the Camera data packets. We are developing the DAQ software adopting the iterative and incremental model in order to maximize the software reuse and to implement a system which is easily adaptable to changes. This contribution presents the Camera DAQ Software architecture with particular emphasis on its potential reuse for the ASTRI/CTA mini-array.
Costless Platform for High Resolution Stereoscopic Images of a High Gothic Facade
NASA Astrophysics Data System (ADS)
Héno, R.; Chandelier, L.; Schelstraete, D.
2012-07-01
In October 2011, the PPMD specialized master's degree students (Photogrammetry, Positionning and Deformation Measurement) of the French ENSG (IGN's School of Geomatics, the Ecole Nationale des Sciences Géographiques) were asked to come and survey the main facade of the cathedral of Amiens, which is very complex as far as size and decoration are concerned. Although it was first planned to use a lift truck for the image survey, budget considerations and taste for experimentation led the project to other perspectives: images shot from the ground level with a long focal camera will be combined to complementary images shot from what higher galleries are available on the main facade with a wide angle camera fixed on a horizontal 2.5 meter long pole. This heteroclite image survey is being processed by the PPMD master's degree students during this academic year. Among other type of products, 3D point clouds will be calculated on specific parts of the facade with both sources of images. If the proposed device and methodology to get full image coverage of the main facade happen to be fruitful, the image acquisition phase will be completed later by another team. This article focuses on the production of 3D point clouds with wide angle images on the rose of the main facade.
Hollywood on tobacco: how the entertainment industry understands tobacco portrayal.
Shields, D L; Carol, J; Balbach, E D; McGee, S
1999-01-01
To determine how people in the California-based entertainment industry think about the portrayal of tobacco use in movies and on television. Specifically, to explore who decides when to include tobacco in a project; how that decision is made; what issues are considered; what messages are intended; whether and how the issue of second-hand smoke is considered; and what advocacy methods might be useful in influencing future decisions about tobacco portrayal. Qualitative in-depth interviews of entertainment industry personnel,with a semi-structured interview protocol to guide the interview. 54 subjects drawn from a convenience sample of writers, actors, directors, producers, studio executives, and others involved in the film industry. Hollywood is heterogeneous with varying perspectives on rates of tobacco use portrayal; intentionality of the decision to use and the necessity to portray tobacco use; and its degree of acceptance of responsibility for influencing societal smoking. Tobacco depiction may originate with the writer, actor, or director and is included most frequently to elucidate character or portray reality. On-camera smoking is influenced by actors' off-camera tobacco use. The research presented can help advocates better understand the norms and values of those working within the entertainment industry and thereby assist them in creating more effective change strategies.
A positional estimation technique for an autonomous land vehicle in an unstructured environment
NASA Technical Reports Server (NTRS)
Talluri, Raj; Aggarwal, J. K.
1990-01-01
This paper presents a solution to the positional estimation problem of an autonomous land vehicle navigating in an unstructured mountainous terrain. A Digital Elevation Map (DEM) of the area in which the robot is to navigate is assumed to be given. It is also assumed that the robot is equipped with a camera that can be panned and tilted, and a device to measure the elevation of the robot above the ground surface. No recognizable landmarks are assumed to be present in the environment in which the robot is to navigate. The solution presented makes use of the DEM information, and structures the problem as a heuristic search in the DEM for the possible robot location. The shape and position of the horizon line in the image plane and the known camera geometry of the perspective projection are used as parameters to search the DEM. Various heuristics drawn from the geometric constraints are used to prune the search space significantly. The algorithm is made robust to errors in the imaging process by accounting for the worst care errors. The approach is tested using DEM data of areas in Colorado and Texas. The method is suitable for use in outdoor mobile robots and planetary rovers.
NASA Technical Reports Server (NTRS)
1997-01-01
Passive millimeter wave (PMMW) sensors have the ability to see through fog, clouds, dust and sandstorms and thus have the potential to support all-weather operations, both military and commercial. Many of the applications, such as military transport or commercial aircraft landing, are technologically stressing in that they require imaging of a scene with a large field of view in real time and with high spatial resolution. The development of a low cost PMMW focal plane array camera is essential to obtain real-time video images to fulfill the above needs. The overall objective of this multi-year project (Phase 1) was to develop and demonstrate the capabilities of a W-band PMMW camera with a microwave/millimeter wave monolithic integrated circuit (MMIC) focal plane array (FPA) that can be manufactured at low cost for both military and commercial applications. This overall objective was met in July 1997 when the first video images from the camera were generated of an outdoor scene. In addition, our consortium partner McDonnell Douglas was to develop a real-time passive millimeter wave flight simulator to permit pilot evaluation of a PMMW-equipped aircraft in a landing scenario. A working version of this simulator was completed. This work was carried out under the DARPA-funded PMMW Camera Technology Reinvestment Project (TRP), also known as the PMMW Camera DARPA Joint Dual-Use Project. In this final report for the Phase 1 activities, a year by year description of what the specific objectives were, the approaches taken, and the progress made is presented, followed by a description of the validation and imaging test results obtained in 1997.
A versatile calibration procedure for portable coded aperture gamma cameras and RGB-D sensors
NASA Astrophysics Data System (ADS)
Paradiso, V.; Crivellaro, A.; Amgarou, K.; de Lanaute, N. Blanc; Fua, P.; Liénard, E.
2018-04-01
The present paper proposes a versatile procedure for the geometrical calibration of coded aperture gamma cameras and RGB-D depth sensors, using only one radioactive point source and a simple experimental set-up. Calibration data is then used for accurately aligning radiation images retrieved by means of the γ-camera with the respective depth images computed with the RGB-D sensor. The system resulting from such a combination is thus able to retrieve, automatically, the distance of radioactive hotspots by means of pixel-wise mapping between gamma and depth images. This procedure is of great interest for a wide number of applications, ranging from precise automatic estimation of the shape and distance of radioactive objects to Augmented Reality systems. Incidentally, the corresponding results validated the choice of a perspective design model for a coded aperture γ-camera.
Stereo optical guidance system for control of industrial robots
NASA Technical Reports Server (NTRS)
Powell, Bradley W. (Inventor); Rodgers, Mike H. (Inventor)
1992-01-01
A device for the generation of basic electrical signals which are supplied to a computerized processing complex for the operation of industrial robots. The system includes a stereo mirror arrangement for the projection of views from opposite sides of a visible indicia formed on a workpiece. The views are projected onto independent halves of the retina of a single camera. The camera retina is of the CCD (charge-coupled-device) type and is therefore capable of providing signals in response to the image projected thereupon. These signals are then processed for control of industrial robots or similar devices.
Opportunistic traffic sensing using existing video sources (phase II).
DOT National Transportation Integrated Search
2017-02-01
The purpose of the project reported on here was to investigate methods for automatic traffic sensing using traffic surveillance : cameras, red light cameras, and other permanent and pre-existing video sources. Success in this direction would potentia...
Control and protection of outdoor embedded camera for astronomy
NASA Astrophysics Data System (ADS)
Rigaud, F.; Jegouzo, I.; Gaudemard, J.; Vaubaillon, J.
2012-09-01
The purpose of CABERNET- Podet-Met (CAmera BEtter Resolution NETwork, Pole sur la Dynamique de l'Environnement Terrestre - Meteor) project is the automated observation, by triangulation with three cameras, of meteor showers to perform a calculation of meteoroids trajectory and velocity. The scientific goal is to search the parent body, comet or asteroid, for each observed meteor. To install outdoor cameras in order to perform astronomy measurements for several years with high reliability requires a very specific design for the box. For these cameras, this contribution shows how we fulfilled the various functions of their boxes, such as cooling of the CCD, heating to melt snow and ice, the protecting against moisture, lightning and Solar light. We present the principal and secondary functions, the product breakdown structure, the technical solutions evaluation grid of criteria, the adopted technology products and their implementation in multifunction subsets for miniaturization purpose. To manage this project, we aim to get the lowest manpower and development time for every part. In appendix, we present the measurements the image quality evolution during the CCD cooling, and some pictures of the prototype.
Power estimation of martial arts movement using 3D motion capture camera
NASA Astrophysics Data System (ADS)
Azraai, Nur Zaidi; Awang Soh, Ahmad Afiq Sabqi; Mat Jafri, Mohd Zubir
2017-06-01
Motion capture camera (MOCAP) has been widely used in many areas such as biomechanics, physiology, animation, arts, etc. This project is done by approaching physics mechanics and the extended of MOCAP application through sports. Most researchers will use a force plate, but this will only can measure the force of impact, but for us, we are keen to observe the kinematics of the movement. Martial arts is one of the sports that uses more than one part of the human body. For this project, martial art `Silat' was chosen because of its wide practice in Malaysia. 2 performers have been selected, one of them has an experienced in `Silat' practice and another one have no experience at all so that we can compare the energy and force generated by the performers. Every performer will generate a punching with same posture which in this project, two types of punching move were selected. Before the measuring start, a calibration has been done so the software knows the area covered by the camera and reduce the error when analyze by using the T stick that have been pasted with a marker. A punching bag with mass 60 kg was hung on an iron bar as a target. The use of this punching bag is to determine the impact force of a performer when they punch. This punching bag also will be stuck with the optical marker so we can observe the movement after impact. 8 cameras have been used and placed with 2 cameras at every side of the wall with different angle in a rectangular room 270 ft2 and the camera covered approximately 50 ft2. We covered only a small area so less noise will be detected and make the measurement more accurate. A Marker has been pasted on the limb of the entire hand that we want to observe and measure. A passive marker used in this project has a characteristic to reflect the infrared that being generated by the camera. The infrared will reflected to the camera sensor so the marker position can be detected and show in software. The used of many cameras is to increase the precision and improve the accuracy of the marker. Performer movement was recorded and analyzed using software Cortex motion analysis where velocity and acceleration of a performer movement can be measured. With classical mechanics approach we have estimated the power and force of impact and shows that an experienced performer produces more power and force of impact is higher than the inexperienced performer.
Preface: The Chang'e-3 lander and rover mission to the Moon
NASA Astrophysics Data System (ADS)
Ip, Wing-Huen; Yan, Jun; Li, Chun-Lai; Ouyang, Zi-Yuan
2014-12-01
The Chang'e-3 (CE-3) lander and rover mission to the Moon was an intermediate step in China's lunar exploration program, which will be followed by a sample return mission. The lander was equipped with a number of remote-sensing instruments including a pair of cameras (Landing Camera and Terrain Camera) for recording the landing process and surveying terrain, an extreme ultraviolet camera for monitoring activities in the Earth's plasmasphere, and a first-ever Moon-based ultraviolet telescope for astronomical observations. The Yutu rover successfully carried out close-up observations with the Panoramic Camera, mineralogical investigations with the VIS-NIR Imaging Spectrometer, study of elemental abundances with the Active Particle-induced X-ray Spectrometer, and pioneering measurements of the lunar subsurface with Lunar Penetrating Radar. This special issue provides a collection of key information on the instrumental designs, calibration methods and data processing procedures used by these experiments with a perspective of facilitating further analyses of scientific data from CE-3 in preparation for future missions.
Active solution of homography for pavement crack recovery with four laser lines.
Xu, Guan; Chen, Fang; Wu, Guangwei; Li, Xiaotao
2018-05-08
An active solution method of the homography, which is derived from four laser lines, is proposed to recover the pavement cracks captured by the camera to the real-dimension cracks in the pavement plane. The measurement system, including a camera and four laser projectors, captures the projection laser points on the 2D reference in different positions. The projection laser points are reconstructed in the camera coordinate system. Then, the laser lines are initialized and optimized by the projection laser points. Moreover, the plane-indicated Plücker matrices of the optimized laser lines are employed to model the laser projection points of the laser lines on the pavement. The image-pavement homography is actively determined by the solutions of the perpendicular feet of the projection laser points. The pavement cracks are recovered by the active solution of homography in the experiments. The recovery accuracy of the active solution method is verified by the 2D dimension-known reference. The test case with the measurement distance of 700 mm and the relative angle of 8° achieves the smallest recovery error of 0.78 mm in the experimental investigations, which indicates the application potentials in the vision-based pavement inspection.
A projective surgical navigation system for cancer resection
NASA Astrophysics Data System (ADS)
Gan, Qi; Shao, Pengfei; Wang, Dong; Ye, Jian; Zhang, Zeshu; Wang, Xinrui; Xu, Ronald
2016-03-01
Near infrared (NIR) fluorescence imaging technique can provide precise and real-time information about tumor location during a cancer resection surgery. However, many intraoperative fluorescence imaging systems are based on wearable devices or stand-alone displays, leading to distraction of the surgeons and suboptimal outcome. To overcome these limitations, we design a projective fluorescence imaging system for surgical navigation. The system consists of a LED excitation light source, a monochromatic CCD camera, a host computer, a mini projector and a CMOS camera. A software program is written by C++ to call OpenCV functions for calibrating and correcting fluorescence images captured by the CCD camera upon excitation illumination of the LED source. The images are projected back to the surgical field by the mini projector. Imaging performance of this projective navigation system is characterized in a tumor simulating phantom. Image-guided surgical resection is demonstrated in an ex-vivo chicken tissue model. In all the experiments, the projected images by the projector match well with the locations of fluorescence emission. Our experimental results indicate that the proposed projective navigation system can be a powerful tool for pre-operative surgical planning, intraoperative surgical guidance, and postoperative assessment of surgical outcome. We have integrated the optoelectronic elements into a compact and miniaturized system in preparation for further clinical validation.
Implicit multiplane 3D camera calibration matrices for stereo image processing
NASA Astrophysics Data System (ADS)
McKee, James W.; Burgett, Sherrie J.
1997-12-01
By implicit camera calibration, we mean the process of calibrating cameras without explicitly computing their physical parameters. We introduce a new implicit model based on a generalized mapping between an image plane and multiple, parallel calibration planes (usually between four to seven planes). This paper presents a method of computing a relationship between a point on a three-dimensional (3D) object and its corresponding two-dimensional (2D) coordinate in a camera image. This relationship is expanded to form a mapping of points in 3D space to points in image (camera) space and visa versa that requires only matrix multiplication operations. This paper presents the rationale behind the selection of the forms of four matrices and the algorithms to calculate the parameters for the matrices. Two of the matrices are used to map 3D points in object space to 2D points on the CCD camera image plane. The other two matrices are used to map 2D points on the image plane to points on user defined planes in 3D object space. The mappings include compensation for lens distortion and measurement errors. The number of parameters used can be increased, in a straight forward fashion, to calculate and use as many parameters as needed to obtain a user desired accuracy. Previous methods of camera calibration use a fixed number of parameters which can limit the obtainable accuracy and most require the solution of nonlinear equations. The procedure presented can be used to calibrate a single camera to make 2D measurements or calibrate stereo cameras to make 3D measurements. Positional accuracy of better than 3 parts in 10,000 have been achieved. The algorithms in this paper were developed and are implemented in MATLABR (registered trademark of The Math Works, Inc.). We have developed a system to analyze the path of optical fiber during high speed payout (unwinding) of optical fiber off a bobbin. This requires recording and analyzing high speed (5 microsecond exposure time), synchronous, stereo images of the optical fiber during payout. A 3D equation for the fiber at an instant in time is calculated from the corresponding pair of stereo images as follows. In each image, about 20 points along the 2D projection of the fiber are located. Each of these 'fiber points' in one image is mapped to its projection line in 3D space. Each projection line is mapped into another line in the second image. The intersection of each mapped projection line and a curve fitted to the fiber points of the second image (fiber projection in second image) is calculated. Each intersection point is mapped back to the 3D space. A 3D fiber coordinate is formed from the intersection, in 3D space, of a mapped intersection point with its corresponding projection line. The 3D equation for the fiber is computed from this ordered list of 3D coordinates. This process requires a method of accurately mapping 2D (image space) to 3D (object space) and visa versa.3173
Sweatt, W.C.
1998-09-08
A projection lithography camera is presented with a wide ringfield optimized so as to make efficient use of extreme ultraviolet radiation from a large area radiation source (e.g., D{sub source} {approx_equal} 0.5 mm). The camera comprises four aspheric mirrors optically arranged on a common axis of symmetry. The camera includes an aperture stop that is accessible through a plurality of partial aperture stops to synthesize the theoretical aperture stop. Radiation from a mask is focused to form a reduced image on a wafer, relative to the mask, by reflection from the four aspheric mirrors. 11 figs.
NASA Technical Reports Server (NTRS)
Schultz, Christopher J.; Lang, Timothy J.; Leake, Skye; Runco, Mario, Jr.; Blakeslee, Richard J.
2017-01-01
Video and still frame images from cameras aboard the International Space Station (ISS) are used to inspire, educate, and provide a unique vantage point from low-Earth orbit that is second to none; however, these cameras have overlooked capabilities for contributing to scientific analysis of the Earth and near-space environment. The goal of this project is to study how geo referenced video/images from available ISS camera systems can be useful for scientific analysis, using lightning properties as a demonstration.
Event-Driven Random-Access-Windowing CCD Imaging System
NASA Technical Reports Server (NTRS)
Monacos, Steve; Portillo, Angel; Ortiz, Gerardo; Alexander, James; Lam, Raymond; Liu, William
2004-01-01
A charge-coupled-device (CCD) based high-speed imaging system, called a realtime, event-driven (RARE) camera, is undergoing development. This camera is capable of readout from multiple subwindows [also known as regions of interest (ROIs)] within the CCD field of view. Both the sizes and the locations of the ROIs can be controlled in real time and can be changed at the camera frame rate. The predecessor of this camera was described in High-Frame-Rate CCD Camera Having Subwindow Capability (NPO- 30564) NASA Tech Briefs, Vol. 26, No. 12 (December 2002), page 26. The architecture of the prior camera requires tight coupling between camera control logic and an external host computer that provides commands for camera operation and processes pixels from the camera. This tight coupling limits the attainable frame rate and functionality of the camera. The design of the present camera loosens this coupling to increase the achievable frame rate and functionality. From a host computer perspective, the readout operation in the prior camera was defined on a per-line basis; in this camera, it is defined on a per-ROI basis. In addition, the camera includes internal timing circuitry. This combination of features enables real-time, event-driven operation for adaptive control of the camera. Hence, this camera is well suited for applications requiring autonomous control of multiple ROIs to track multiple targets moving throughout the CCD field of view. Additionally, by eliminating the need for control intervention by the host computer during the pixel readout, the present design reduces ROI-readout times to attain higher frame rates. This camera (see figure) includes an imager card consisting of a commercial CCD imager and two signal-processor chips. The imager card converts transistor/ transistor-logic (TTL)-level signals from a field programmable gate array (FPGA) controller card. These signals are transmitted to the imager card via a low-voltage differential signaling (LVDS) cable assembly. The FPGA controller card is connected to the host computer via a standard peripheral component interface (PCI).
Harbour surveillance with cameras calibrated with AIS data
NASA Astrophysics Data System (ADS)
Palmieri, F. A. N.; Castaldo, F.; Marino, G.
The inexpensive availability of surveillance cameras, easily connected in network configurations, suggests the deployment of this additional sensor modality in port surveillance. Vessels appearing within cameras fields of view can be recognized and localized providing to fusion centers information that can be added to data coming from Radar, Lidar, AIS, etc. Camera systems, that are used as localizers however, must be properly calibrated in changing scenarios where often there is limited choice on the position on which they are deployed. Automatic Identification System (AIS) data, that includes position, course and vessel's identity, freely available through inexpensive receivers, for some of the vessels appearing within the field of view, provide the opportunity to achieve proper camera calibration to be used for the localization of vessels not equipped with AIS transponders. In this paper we assume a pinhole model for camera geometry and propose perspective matrices computation using AIS positional data. Images obtained from calibrated cameras are then matched and pixel association is utilized for other vessel's localization. We report preliminary experimental results of calibration and localization using two cameras deployed on the Gulf of Naples coastline. The two cameras overlook a section of the harbour and record short video sequences that are synchronized offline with AIS positional information of easily-identified passenger ships. Other small vessels, not equipped with AIS transponders, are localized using camera matrices and pixel matching. Localization accuracy is experimentally evaluated as a function of target distance from the sensors.
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.
NASA Astrophysics Data System (ADS)
Trott, Carlie D.
Few studies have examined how youth think about, and take action on climate change and far fewer have sought to facilitate their engagement using participatory methods. This dissertation evaluated the impacts of Science, Camera, Action! (SCA), a novel after-school program that combined climate change education with participatory action through photovoice. The specific aims of this study were to: (1) Evaluate the impacts of SCA on youth participants' climate change knowledge, attitudes, and behaviors; (2) Examine how SCA participation served to empower youth agency; and (3) Explore SCA's influence on youths' science engagement. Participants were 55 youths (ages 10 to 12) across three Boys and Girls Club sites in Northern Colorado. SCA's Science component used interactive activities to demonstrate the interrelationships between Earth's changing climate, ecosystems, and sustainable actions within communities. Photovoice, SCA's Camera component, was used to explore youths' climate change perspectives and to identify opportunities for their active engagement. Finally, SCA's Action component aimed to cultivate youth potential as agents of change in their families and communities through the development and implementation of youth-led action projects. Action projects included local policy advocacy, a tree-planting campaign, a photo gallery opening, development of a website, and the establishment of a Boys and Girls Club community garden. To evaluate SCA impacts, a combination of survey and focus group methods were used. Following the program, youth demonstrated increased knowledge of the scientific and social dimensions of the causes and consequences of climate change, as well as its solutions through human action. Though participants expressed a mix of positive (e.g., hope) and negative (e.g., sadness) emotions about climate change, they left the program with an increased sense of respect for nature, an enhanced sense of environmental responsibility, and a greater sense of urgency towards the need for climate change action. Further, participants reported increased engagement in personal pro-environmental behaviors, an enhanced sense of agency in the context of climate change, and provided strong evidence of their role as agents of change in family and community contexts. Through SCA, participants gained a deeper appreciation for science (e.g., in school, careers, and society) and reported increased interest, participation, confidence, and performance in school science. Findings contribute to the vast and growing psychology literature on climate change perceptions and action, and from the understudied perspective of youth. Through a combination of innovative methods and interactive projects, the youth in this study gained a number of psychosocial and educational benefits, while tangibly contributing to the sustainable transformation of their families and communities. Findings of this dissertation have implications for educational programs, youth organizing, and interventions aimed to strengthen youths' active engagement with critical social and scientific issues that impact their lives.
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.
Erosion by Scarp Retreat in Gale Crater
2013-12-09
This mosaic of images from the Mast Camera onboard NASA Curiosity Mars rover shows a series of sedimentary deposits in the Glenelg area of Gale Crater, from a perspective in Yellowknife Bay looking toward west-northwest.
PRIMAS: a real-time 3D motion-analysis system
NASA Astrophysics Data System (ADS)
Sabel, Jan C.; van Veenendaal, Hans L. J.; Furnee, E. Hans
1994-03-01
The paper describes a CCD TV-camera-based system for real-time multicamera 2D detection of retro-reflective targets and software for accurate and fast 3D reconstruction. Applications of this system can be found in the fields of sports, biomechanics, rehabilitation research, and various other areas of science and industry. The new feature of real-time 3D opens an even broader perspective of application areas; animations in virtual reality are an interesting example. After presenting an overview of the hardware and the camera calibration method, the paper focuses on the real-time algorithms used for matching of the images and subsequent 3D reconstruction of marker positions. When using a calibrated setup of two cameras, it is now possible to track at least ten markers at 100 Hz. Limitations in the performance are determined by the visibility of the markers, which could be improved by adding a third camera.
Teaching optics concepts through an approach that emphasizes the colors of nature
NASA Astrophysics Data System (ADS)
Pompea, Stephen M.; Carsten-Conner, Laura D.
2015-10-01
A wide variety of optics concepts can be taught using the overall perspective of "colors of nature" as a guiding and unifying theme. This approach is attractive and interesting with a wide appeal to children, nature enthusiasts, photographers, and artists. This approach also encourages a deep understanding of the natural world and the role of coloration in biology, remote sensing, the aurora, mineralogy, meteorology, in human-made objects, and astronomy, to name a few. Third, using this theme promotes a close look at optical phenomena at all size scales-from the microscopic (e.g. silica spheres in opals) to the mid-scale (the aurora), to the largest scale (astronomical phenomena such as gaseous emission nebula). Fourth, the natural and human-constructed world provides accessible and beautiful examples of complex phenomena such as interference, diffraction, atomic and molecular emissions, Rayleigh and Mie scattering, illumination engineering, and fluorescence. These areas can be explored successfully in the context of "colors of nature". Finally, using the "colors of nature" also promotes an understanding of technology, from flashlights to streetlights, from telescopes and binoculars, to spectrometers and digital cameras. For examples something as simple as how to set the white balance on a digital camera to get a realistic looking photograph can lead to a lengthy exploration of spectrally selective surfaces and their reflectance, the nature of different illumination sources, the meaning of color temperature, and role of calibration in a digital image. We have used this approach of teaching using the colors of nature as an organizing theme in our NSF-funded project "Project STEAM: Integrating Art with Science to Build Science Identities Among Girls" (colorsofnature.org).
Qualification of Engineering Camera for Long-Duration Deep Space Missions
NASA Technical Reports Server (NTRS)
Ramesham, Rajeshuni; Maki, Justin N.; Pourangi, Ali M.; Lee, Steven W.
2012-01-01
Qualification and verification of advanced electronic packaging and interconnect technologies, and various other types of hardware elements for the Mars Exploration Rover s Spirit and Opportunity (MER)/Mars Science Laboratory (MSL) flight projects, has been performed to enhance the mission assurance. The qualification of hardware (engineering camera) under extreme cold temperatures has been performed with reference to various Mars-related project requirements. The flight-like packages, sensors, and subassemblies have been selected for the study to survive three times the total number of expected diurnal temperature cycles resulting from all environmental and operational exposures occurring over the life of the flight hardware, including all relevant manufacturing, ground operations, and mission phases. Qualification has been performed by subjecting above flight-like hardware to the environmental temperature extremes, and assessing any structural failures or degradation in electrical performance due to either overstress or thermal cycle fatigue. Engineering camera packaging designs, charge-coupled devices (CCDs), and temperature sensors were successfully qualified for MER and MSL per JPL design principles. Package failures were observed during qualification processes and the package redesigns were then made to enhance the reliability and subsequent mission assurance. These results show the technology certainly is promising for MSL, and especially for longterm extreme temperature missions to the extreme temperature conditions. The engineering camera has been completely qualified for the MSL project, with the proven ability to survive on Mars for 2010 sols, or 670 sols times three. Finally, the camera continued to be functional, even after 2010 thermal cycles.
Zahl, D A; Schrader, S M; Edwards, P C
2018-05-01
This exploratory study evaluated student perceptions of their ability to self- and peer assess (i) interpersonal communication skills and (ii) clinical procedures (a head and neck examination) during standardised patient (SP) interactions recorded by Google Glass compared to a static camera. Students compared the Google Glass and static camera recordings using an instrument consisting of 20 Likert-type items and four open- and closed-text items. The Likert-type items asked students to rate how effectively they could assess specific aspects of interpersonal communication and a head and neck examination in these two different types of recordings. The interpersonal communication items included verbal, paraverbal and non-verbal subscales. The open- and closed-text items asked students to report on more globally the differences between the two types of recordings. Descriptive and inferential statistical analyses were conducted for all survey items. An inductive thematic analysis was conducted to determine qualitative emergent themes from the open-text questions. Students found the Glass videos more effective for assessing verbal (t 22 = 2.091, P = 0.048) and paraverbal communication skills (t 22 = 3.304, P = 0.003), whilst they reported that the static camera video was more effective for assessing non-verbal communication skills (t 22 = -2.132, P = 0.044). Four principle themes emerged from the students' open-text responses comparing Glass to static camera recordings for self- and peer assessment: (1) first-person perspective, (2) assessment of non-verbal communication, (3) audiovisual experience and (4) student operation of Glass. Our findings suggest that students perceive that Google Glass is a valuable tool for facilitating self- and peer assessment of SP examinations because of students' perceived ability to emphasise and illustrate communicative and clinical activities from a first-person perspective. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Shape equivalence under perspective and projective transformations.
Wagemans, J; Lamote, C; Van Gool, L
1997-06-01
When a planar shape is viewed obliquely, it is deformed by a perspective deformation. If the visual system were to pick up geometrical invariants from such projections, these would necessarily be invariant under the wider class of projective transformations. To what extent can the visual system tell the difference between perspective and nonperspective but still projective deformations of shapes? To investigate this, observers were asked to indicate which of two test patterns most resembled a standard pattern. The test patterns were related to the standard pattern by a perspective or projective transformation, or they were completely unrelated. Performance was slightly better in a matching task with perspective and unrelated test patterns (92.6%) than in a projective-random matching task (88.8%). In a direct comparison, participants had a small preference (58.5%) for the perspectively related patterns over the projectively related ones. Preferences were based on the values of the transformation parameters (slant and shear). Hence, perspective and projective transformations yielded perceptual differences, but they were not treated in a categorically different manner by the human visual system.
DOT National Transportation Integrated Search
2014-10-01
The goal of this project is to monitor traffic flow continuously with an innovative camera system composed of a custom : designed image sensor integrated circuit (IC) containing trapezoid pixel array and camera system that is capable of : intelligent...
NASA Technical Reports Server (NTRS)
Bothwell, Mary
2004-01-01
My division was charged with building a suite of cameras for the Mars Exploration Rover (MER) project. We were building the science cameras on the mass assembly, the microscope camera, and the hazard and navigation cameras for the rovers. Not surprisingly, a lot of folks were paying attention to our work - because there's really no point in landing on Mars if you can't take pictures. In Spring 2002 things were not looking good. The electronics weren't coming in, and we had to go back to the vendors. The vendors would change the design, send the boards back, and they wouldn't work. On our side, we had an instrument manager in charge who I believe has the potential to become a great manager, but when things got behind schedule he didn't have the experience to know what was needed to catch up. As division manager, I was ultimately responsible for seeing that all my project and instrument managers delivered their work. I had to make the decision whether or not to replace him.
Daniel, Lorias Espinoza; Tapia, Fernando Montes; Arturo, Minor Martínez; Ricardo, Ordorica Flores
2014-12-01
The ability to handle and adapt to the visual perspectives generated by angled laparoscopes is crucial for skilled laparoscopic surgery. However, the control of the visual work space depends on the ability of the operator of the camera, who is often not the most experienced member of the surgical team. Here, we present a simple, low-cost option for surgical training that challenges the learner with static and dynamic visual perspectives at 30 degrees using a system that emulates the angled laparoscope. A system was developed using a low-cost camera and readily available materials to emulate the angled laparoscope. Nine participants undertook 3 tasks to test spatial adaptation to the static and dynamic visual perspectives at 30 degrees. Completing each task to a predefined satisfactory level ensured precision of execution of the tasks. Associated metrics (time and error rate) were recorded, and the performance of participants were determined. A total of 450 repetitions were performed by 9 residents at various stages of training. All the tasks were performed with a visual perspective of 30 degrees using the system. Junior residents were more proficient than senior residents. This system is a viable and low-cost alternative for developing the basic psychomotor skills necessary for the handling and adaptation to visual perspectives of 30 degrees, without depending on a laparoscopic tower, in junior residents. More advanced skills may then be acquired by other means, such as in the operating theater or through clinical experience.
Localization and Mapping Using a Non-Central Catadioptric Camera System
NASA Astrophysics Data System (ADS)
Khurana, M.; Armenakis, C.
2018-05-01
This work details the development of an indoor navigation and mapping system using a non-central catadioptric omnidirectional camera and its implementation for mobile applications. Omnidirectional catadioptric cameras find their use in navigation and mapping of robotic platforms, owing to their wide field of view. Having a wider field of view, or rather a potential 360° field of view, allows the system to "see and move" more freely in the navigation space. A catadioptric camera system is a low cost system which consists of a mirror and a camera. Any perspective camera can be used. A platform was constructed in order to combine the mirror and a camera to build a catadioptric system. A calibration method was developed in order to obtain the relative position and orientation between the two components so that they can be considered as one monolithic system. The mathematical model for localizing the system was determined using conditions based on the reflective properties of the mirror. The obtained platform positions were then used to map the environment using epipolar geometry. Experiments were performed to test the mathematical models and the achieved location and mapping accuracies of the system. An iterative process of positioning and mapping was applied to determine object coordinates of an indoor environment while navigating the mobile platform. Camera localization and 3D coordinates of object points obtained decimetre level accuracies.
Slip Face on Downwind Side of Namib Sand Dune on Mars
2016-01-04
This view from NASA's Curiosity Mars Rover shows the downwind side of "Namib Dune," which stands about 13 feet (4 meters) high. The site is part of Bagnold Dunes, a band of dark sand dunes along the northwestern flank of Mars' Mount Sharp. The component images stitched together into this scene were taken with Curiosity's Navigation Camera (Navcam) on Dec. 17, 2015, during the 1,196th Martian day, or sol, of the rover's work on Mars. In late 2015 and early 2016, Curiosity is conducting the first up-close studies ever made of active sand dunes anywhere but on Earth. Under the influence of Martian wind, the Bagnold Dunes are migrating up to about one yard or meter per Earth year. The view spans from westward on the left to east-southeastward on the right. It is presented as a cylindrical perspective projection. http://photojournal.jpl.nasa.gov/catalog/PIA20281
Making Tracks on Mars (left-eye)
NASA Technical Reports Server (NTRS)
2004-01-01
NASA's Mars Exploration Rover Spirit has been making tracks on Mars for seven months now, well beyond its original 90-day mission. The rover traveled more than 3 kilometers (2 miles) to reach the 'Columbia Hills' pictured here. In this 360-degree view of the rolling martian terrain, its wheel tracks can be seen approaching from the northwest (right side of image). Spirit's navigation camera took the images that make up this mosaic on sols 210 and 213 (Aug. 5 and Aug. 8, 2004). The rover is now conducting scientific studies of the local geology on the 'Clovis' outcrop of the 'West Spur' region of the 'Columbia Hills.' The view is presented in a cylindrical-perspective projection with geometrical seam correction. This is the left-eye view of a stereo pair. Scientists plan for Spirit to take a color panoramic image from this location.Measuring Positions of Objects using Two or More Cameras
NASA Technical Reports Server (NTRS)
Klinko, Steve; Lane, John; Nelson, Christopher
2008-01-01
An improved method of computing positions of objects from digitized images acquired by two or more cameras (see figure) has been developed for use in tracking debris shed by a spacecraft during and shortly after launch. The method is also readily adaptable to such applications as (1) tracking moving and possibly interacting objects in other settings in order to determine causes of accidents and (2) measuring positions of stationary objects, as in surveying. Images acquired by cameras fixed to the ground and/or cameras mounted on tracking telescopes can be used in this method. In this method, processing of image data starts with creation of detailed computer- aided design (CAD) models of the objects to be tracked. By rotating, translating, resizing, and overlaying the models with digitized camera images, parameters that characterize the position and orientation of the camera can be determined. The final position error depends on how well the centroids of the objects in the images are measured; how accurately the centroids are interpolated for synchronization of cameras; and how effectively matches are made to determine rotation, scaling, and translation parameters. The method involves use of the perspective camera model (also denoted the point camera model), which is one of several mathematical models developed over the years to represent the relationships between external coordinates of objects and the coordinates of the objects as they appear on the image plane in a camera. The method also involves extensive use of the affine camera model, in which the distance from the camera to an object (or to a small feature on an object) is assumed to be much greater than the size of the object (or feature), resulting in a truly two-dimensional image. The affine camera model does not require advance knowledge of the positions and orientations of the cameras. This is because ultimately, positions and orientations of the cameras and of all objects are computed in a coordinate system attached to one object as defined in its CAD model.
Desai, Nandini J.; Gupta, B. D.; Patel, Pratik Narendrabhai
2014-01-01
Introduction: Obtaining images of slides viewed by a microscope can be invaluable for both diagnosis and teaching.They can be transferred among technologically-advanced hospitals for further consultation and evaluation. But a standard microscopic photography camera unit (MPCU)(MIPS-Microscopic Image projection System) is costly and not available in resource poor settings. The aim of our endeavour was to find a comparable and cheaper alternative method for photomicrography. Materials and Methods: We used a NIKON Coolpix S6150 camera (box type digital camera) with Olympus CH20i microscope and a fluorescent microscope for the purpose of this study. Results: We got comparable results for capturing images of light microscopy, but the results were not as satisfactory for fluorescent microscopy. Conclusion: A box type digital camera is a comparable, less expensive and convenient alternative to microscopic photography camera unit. PMID:25478350
Brute Force Matching Between Camera Shots and Synthetic Images from Point Clouds
NASA Astrophysics Data System (ADS)
Boerner, R.; Kröhnert, M.
2016-06-01
3D point clouds, acquired by state-of-the-art terrestrial laser scanning techniques (TLS), provide spatial information about accuracies up to several millimetres. Unfortunately, common TLS data has no spectral information about the covered scene. However, the matching of TLS data with images is important for monoplotting purposes and point cloud colouration. Well-established methods solve this issue by matching of close range images and point cloud data by fitting optical camera systems on top of laser scanners or rather using ground control points. The approach addressed in this paper aims for the matching of 2D image and 3D point cloud data from a freely moving camera within an environment covered by a large 3D point cloud, e.g. a 3D city model. The key advantage of the free movement affects augmented reality applications or real time measurements. Therefore, a so-called real image, captured by a smartphone camera, has to be matched with a so-called synthetic image which consists of reverse projected 3D point cloud data to a synthetic projection centre whose exterior orientation parameters match the parameters of the image, assuming an ideal distortion free camera.
Data filtering with support vector machines in geometric camera calibration.
Ergun, B; Kavzoglu, T; Colkesen, I; Sahin, C
2010-02-01
The use of non-metric digital cameras in close-range photogrammetric applications and machine vision has become a popular research agenda. Being an essential component of photogrammetric evaluation, camera calibration is a crucial stage for non-metric cameras. Therefore, accurate camera calibration and orientation procedures have become prerequisites for the extraction of precise and reliable 3D metric information from images. The lack of accurate inner orientation parameters can lead to unreliable results in the photogrammetric process. A camera can be well defined with its principal distance, principal point offset and lens distortion parameters. Different camera models have been formulated and used in close-range photogrammetry, but generally sensor orientation and calibration is performed with a perspective geometrical model by means of the bundle adjustment. In this study, support vector machines (SVMs) using radial basis function kernel is employed to model the distortions measured for Olympus Aspherical Zoom lens Olympus E10 camera system that are later used in the geometric calibration process. It is intended to introduce an alternative approach for the on-the-job photogrammetric calibration stage. Experimental results for DSLR camera with three focal length settings (9, 18 and 36 mm) were estimated using bundle adjustment with additional parameters, and analyses were conducted based on object point discrepancies and standard errors. Results show the robustness of the SVMs approach on the correction of image coordinates by modelling total distortions on-the-job calibration process using limited number of images.
Hyun, Jong Jin; Keum, Bora; Seo, Yeon Seok; Kim, Yong Sik; Jeen, Yoon Tae; Lee, Hong Sik; Um, Soon Ho; Kim, Chang Duck; Ryu, Ho Sang; Lim, Jong-Wook; Woo, Dong-Gi; Kim, Young-Joong; Lim, Myo-Taeg
2012-01-01
Background/Aims Three-dimensional (3D) imaging is gaining popularity and has been partly adopted in laparoscopic surgery or robotic surgery but has not been applied to gastrointestinal endoscopy. As a first step, we conducted an experiment to evaluate whether images obtained by conventional gastrointestinal endoscopy could be used to acquire quantitative 3D information. Methods Two endoscopes (GIF-H260) were used in a Borrmann type I tumor model made of clay. The endoscopes were calibrated by correcting the barrel distortion and perspective distortion. Obtained images were converted to gray-level image, and the characteristics of the images were obtained by edge detection. Finally, data on 3D parameters were measured by using epipolar geometry, two view geometry, and pinhole camera model. Results The focal length (f) of endoscope at 30 mm was 258.49 pixels. Two endoscopes were fixed at predetermined distance, 12 mm (d12). After matching and calculating disparity (v2-v1), which was 106 pixels, the calculated length between the camera and object (L) was 29.26 mm. The height of the object projected onto the image (h) was then applied to the pinhole camera model, and the result of H (height and width) was 38.21 mm and 41.72 mm, respectively. Measurements were conducted from 2 different locations. The measurement errors ranged from 2.98% to 7.00% with the current Borrmann type I tumor model. Conclusions It was feasible to obtain parameters necessary for 3D analysis and to apply the data to epipolar geometry with conventional gastrointestinal endoscope to calculate the size of an object. PMID:22977798
Wearable Technology to Garner the Perspective of Dementia Family Caregivers
Matthews, Judith T.; Campbell, Grace B.; Hunsaker, Amanda E.; Klinger, Julie; Mecca, Laurel Person; Hu, Lu; Hostein, Sally; Lingler, Jennifer H.
2015-01-01
Family caregivers of persons with dementia typically have limited opportunity during brief clinical encounters to describe the dementia-related behaviors and interactions that they find difficult to handle. Lack of objective data depicting the nature, intensity, and impact of these manifestations of the underlying disease further constrains the extent to which strategies recommended by nurses or other health care providers can be tailored to the situation. We describe a prototype wearable camera system used to gather image and voice data from the caregiver’s perspective in a pilot feasibility intervention study conducted with 18 caregiving dyads. Several scenarios are presented that incorporate salient events (i.e., behaviors or interactions deemed difficult by the caregiver or identified as concerning by our team during screening) identified in the resulting video. We anticipate that future wearable camera systems and software will automate screening for salient events, providing new tools for assessment and intervention by nurses. PMID:26468655
Touchscreen everywhere: on transferring a normal planar surface to a touch-sensitive display.
Dai, Jingwen; Chung, Chi-Kit Ronald
2014-08-01
We address how a human-computer interface with small device size, large display, and touch-input facility can be made possible by a mere projector and camera. The realization is through the use of a properly embedded structured light sensing scheme that enables a regular light-colored table surface to serve the dual roles of both a projection screen and a touch-sensitive display surface. A random binary pattern is employed to code structured light in pixel accuracy, which is embedded into the regular projection display in a way that the user perceives only regular display but not the structured pattern hidden in the display. With the projection display on the table surface being imaged by a camera, the observed image data, plus the known projection content, can work together to probe the 3-D workspace immediately above the table surface, like deciding if there is a finger present and if the finger touches the table surface, and if so, at what position on the table surface the contact is made. All the decisions hinge upon a careful calibration of the projector-camera-table surface system, intelligent segmentation of the hand in the image data, and exploitation of the homography mapping existing between the projector's display panel and the camera's image plane. Extensive experimentation including evaluation of the display quality, hand segmentation accuracy, touch detection accuracy, trajectory tracking accuracy, multitouch capability and system efficiency are shown to illustrate the feasibility of the proposed realization.
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.
Digital Camera Project Fosters Communication Skills
ERIC Educational Resources Information Center
Fisher, Ashley; Lazaros, Edward J.
2009-01-01
This article details the many benefits of educators' use of digital camera technology and provides an activity in which students practice taking portrait shots of classmates, manipulate the resulting images, and add language arts practice by interviewing their subjects to produce a photo-illustrated Word document. This activity gives…
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.
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.
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.
Blur spot limitations in distal endoscope sensors
NASA Astrophysics Data System (ADS)
Yaron, Avi; Shechterman, Mark; Horesh, Nadav
2006-02-01
In years past, the picture quality of electronic video systems was limited by the image sensor. In the present, the resolution of miniature image sensors, as in medical endoscopy, is typically superior to the resolution of the optical system. This "excess resolution" is utilized by Visionsense to create stereoscopic vision. Visionsense has developed a single chip stereoscopic camera that multiplexes the horizontal dimension of the image sensor into two (left and right) images, compensates the blur phenomena, and provides additional depth resolution without sacrificing planar resolution. The camera is based on a dual-pupil imaging objective and an image sensor coated by an array of microlenses (a plenoptic camera). The camera has the advantage of being compact, providing simultaneous acquisition of left and right images, and offering resolution comparable to a dual chip stereoscopic camera with low to medium resolution imaging lenses. A stereoscopic vision system provides an improved 3-dimensional perspective of intra-operative sites that is crucial for advanced minimally invasive surgery and contributes to surgeon performance. An additional advantage of single chip stereo sensors is improvement of tolerance to electronic signal noise.
NASA Astrophysics Data System (ADS)
Servin, Manuel; Padilla, Moises; Garnica, Guillermo; Gonzalez, Adonai
2016-12-01
In this work we review and combine two techniques that have been recently published for three-dimensional (3D) fringe projection profilometry and phase unwrapping, namely: co-phased profilometry and 2-steps temporal phase-unwrapping. By combining these two methods we get a more accurate, higher signal-to-noise 3D profilometer for discontinuous industrial objects. In single-camera single-projector (standard) profilometry, the camera and the projector must form an angle between them. The phase-sensitivity of the profilometer depends on this angle, so it cannot be avoided. This angle produces regions with self-occluding shadows and glare from the solid as viewed from the camera's perspective, making impossible the demodulation of the fringe-pattern there. In other words, the phase data is undefined at those shadow regions. As published recently, this limitation can be solved by using several co-phased fringe-projectors and a single camera. These co-phased projectors are positioned at different directions towards the object, and as a consequence most shadows are compensated. In addition to this, most industrial objects are highly discontinuous, which precludes the use of spatial phase-unwrappers. One way to avoid spatial unwrapping is to decrease the phase-sensitivity to a point where the demodulated phase is bounded to one lambda, so the need for phase-unwrapping disappears. By doing this, however, the recovered non-wrapped phase contains too much harmonic distortion and noise. Using our recently proposed two-step temporal phase-unwrapping technique, the high-sensitivity phase is unwrapped using the low-frequency one as initial gross estimation. This two-step unwrapping technique solves the 3D object discontinuities while keeping the accuracy of the high-frequency profilometry data. In scientific research, new art are derived as logical and consistent result of previous efforts in the same direction. Here we present a new 3D-profilometer combining these two recently published methods: co-phased profilometry and two-steps temporal phase-unwrapping. By doing this, we obtain a new and more powerful 3D profilometry technique which overcomes the two main limitations of previous fringe-projection profilometers namely: high phase-sensitivity digitalization of discontinuous objects and solid's self-generated shadow minimization. This new 3D profilometer is demonstrated by an experiment digitizing a discontinuous 3D industrial-solid where the advantages of this new profilometer with respect to previous art are clearly shown.
Pink, Sarah
2015-06-01
Engaging first person perspective recording as a type of digital ethnography invites the question of how we might understand the status of the knowledge it produces. To examine this question I will focus on how first person perspective camera recordings might be engaged and made analytically meaningful in disciplines where naturalistic and observational visual recording is uncommon and where the idea of producing naturalistic or optimally objective visual recordings of people's lives is problematized. In doing so I explore the wider possibilities of these technologies for ethnographic research both beyond their existing uses and for interdisciplinary research where the images they produce might be analysed from more than one perspective.
A 2.5m astronomical telescope project
NASA Astrophysics Data System (ADS)
Phaichith, Oudomsanith
2008-07-01
The paper reports a recently started project for a 2,5 meter diameter robotic telescope dedicated to astronomy and education for the University of Moscow's Sternberg Institute. As a prime contractor Sagem Defense Securite's REOSC department will take on the program design as well as the production of the optical components. The project includes the Alt-Az mount, the dome and its cooling and air stabilization system, the weather station, the high-resolution camera and realization, transport and installation on-site at the Kislovodsk solar station located in the Caucasus mountains as well as the initial training for the operators. The telescope will provide a wide field of view of 40 arcmin at the Cassegrain F/8 focus. An escapable and rotating tertiary mirror will allow to direct the light to the two Nasmyth foci and two student ports located at 90° from the Nasmyth foci. A 4k x 4k CCD camera cryogenically cooled to 140 K will be provided as a first light camera. All will be delivered by end 2009. Remotely controlled via the internet, the telescope will allow Russia to train doctors in astronomy, participate in international research projects and draw up the future specifications of a larger and more advanced telescope.
Camera-pose estimation via projective Newton optimization on the manifold.
Sarkis, Michel; Diepold, Klaus
2012-04-01
Determining the pose of a moving camera is an important task in computer vision. In this paper, we derive a projective Newton algorithm on the manifold to refine the pose estimate of a camera. The main idea is to benefit from the fact that the 3-D rigid motion is described by the special Euclidean group, which is a Riemannian manifold. The latter is equipped with a tangent space defined by the corresponding Lie algebra. This enables us to compute the optimization direction, i.e., the gradient and the Hessian, at each iteration of the projective Newton scheme on the tangent space of the manifold. Then, the motion is updated by projecting back the variables on the manifold itself. We also derive another version of the algorithm that employs homeomorphic parameterization to the special Euclidean group. We test the algorithm on several simulated and real image data sets. Compared with the standard Newton minimization scheme, we are now able to obtain the full numerical formula of the Hessian with a 60% decrease in computational complexity. Compared with Levenberg-Marquardt, the results obtained are more accurate while having a rather similar complexity.
Mapping Sequence performed during the STS-118 R-Bar Pitch Maneuver
2007-08-10
ISS015-E-21335 (10 Aug. 2007) --- This is one of a series of images photographed with a digital still camera using an 800mm focal length featuring the different areas of the Space Shuttle Endeavour as it approached the International Space Station and performed a back-flip to accommodate close scrutiny by eyeballs and cameras. This image is an almost nadir perspective over Endeavour's of aft cabin and its docking system. Distance between the station and shuttle at this time was approximately 600 feet.
NASA Astrophysics Data System (ADS)
Scopatz, Stephen D.; Mendez, Michael; Trent, Randall
2015-05-01
The projection of controlled moving targets is key to the quantitative testing of video capture and post processing for Motion Imagery. This presentation will discuss several implementations of target projectors with moving targets or apparent moving targets creating motion to be captured by the camera under test. The targets presented are broadband (UV-VIS-IR) and move in a predictable, repeatable and programmable way; several short videos will be included in the presentation. Among the technical approaches will be targets that move independently in the camera's field of view, as well targets that change size and shape. The development of a rotating IR and VIS 4 bar target projector with programmable rotational velocity and acceleration control for testing hyperspectral cameras is discussed. A related issue for motion imagery is evaluated by simulating a blinding flash which is an impulse of broadband photons in fewer than 2 milliseconds to assess the camera's reaction to a large, fast change in signal. A traditional approach of gimbal mounting the camera in combination with the moving target projector is discussed as an alternative to high priced flight simulators. Based on the use of the moving target projector several standard tests are proposed to provide a corresponding test to MTF (resolution), SNR and minimum detectable signal at velocity. Several unique metrics are suggested for Motion Imagery including Maximum Velocity Resolved (the measure of the greatest velocity that is accurately tracked by the camera system) and Missing Object Tolerance (measurement of tracking ability when target is obscured in the images). These metrics are applicable to UV-VIS-IR wavelengths and can be used to assist in camera and algorithm development as well as comparing various systems by presenting the exact scenes to the cameras in a repeatable way.
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.
NASA Technical Reports Server (NTRS)
Ivanov, Anton B.
2003-01-01
The Mars Orbiter Camera (MOC) has been operating on board of the Mars Global Surveyor (MGS) spacecraft since 1998. It consists of three cameras - Red and Blue Wide Angle cameras (FOV=140 deg.) and Narrow Angle camera (FOV=0.44 deg.). The Wide Angle camera allows surface resolution down to 230 m/pixel and the Narrow Angle camera - down to 1.5 m/pixel. This work is a continuation of the project, which we have reported previously. Since then we have refined and improved our stereo correlation algorithm and have processed many more stereo pairs. We will discuss results of our stereo pair analysis located in the Mars Exploration rovers (MER) landing sites and address feasibility of recovering topography from stereo pairs (especially in the polar regions), taken during MGS 'Relay-16' mode.
Head-coupled remote stereoscopic camera system for telepresence applications
NASA Astrophysics Data System (ADS)
Bolas, Mark T.; Fisher, Scott S.
1990-09-01
The Virtual Environment Workstation Project (VIEW) at NASA's Ames Research Center has developed a remotely controlled stereoscopic camera system that can be used for telepresence research and as a tool to develop and evaluate configurations for head-coupled visual systems associated with space station telerobots and remote manipulation robotic arms. The prototype camera system consists of two lightweight CCD video cameras mounted on a computer controlled platform that provides real-time pan, tilt, and roll control of the camera system in coordination with head position transmitted from the user. This paper provides an overall system description focused on the design and implementation of the camera and platform hardware configuration and the development of control software. Results of preliminary performance evaluations are reported with emphasis on engineering and mechanical design issues and discussion of related psychophysiological effects and objectives.
Measuring Distances Using Digital Cameras
ERIC Educational Resources Information Center
Kendal, Dave
2007-01-01
This paper presents a generic method of calculating accurate horizontal and vertical object distances from digital images taken with any digital camera and lens combination, where the object plane is parallel to the image plane or tilted in the vertical plane. This method was developed for a project investigating the size, density and spatial…
Digital Video Cameras for Brainstorming and Outlining: The Process and Potential
ERIC Educational Resources Information Center
Unger, John A.; Scullion, Vicki A.
2013-01-01
This "Voices from the Field" paper presents methods and participant-exemplar data for integrating digital video cameras into the writing process across postsecondary literacy contexts. The methods and participant data are part of an ongoing action-based research project systematically designed to bring research and theory into practice…
Communities, Cameras, and Conservation
ERIC Educational Resources Information Center
Patterson, Barbara
2012-01-01
Communities, Cameras, and Conservation (CCC) is the most exciting and valuable program the author has seen in her 30 years of teaching field science courses. In this citizen science project, students and community volunteers collect data on mountain lions ("Puma concolor") at four natural areas and public parks along the Front Range of Colorado.…
VizieR Online Data Catalog: Hubble Tarantula Treasury Project (HTTP). III. (Sabbi+, 2016)
NASA Astrophysics Data System (ADS)
Sabbi, E.; Lennon, D. J.; Anderson, J.; Cignoni, M.; van der Marel, R. P.; Zaritsky, D.; de Marchi, G.; Panagia, N.; Gouliermis, D. A.; Grebel, E. K.; Gallagher, J. S., III; Smith, L. J.; Sana, H.; Aloisi, A.; Tosi, M.; Evans, C. J.; Arab, H.; Boyer, M.; de Mink, S. E.; Gordon, K.; Koekemoer, A. M.; Larsen, S. S.; Ryon, J. E.; Zeidler, P.
2016-02-01
Hubble Tarantula Treasury Project (HTTP; HST 12939, PI Elena Sabbi + HST 12499, PI Danny Lennon) was awarded 60 orbits of HST time in cycle 20 to survey the entire Tarantula Nebula (30 Doradus), using both the UVIS and the IR channels of the Wide Field Camera 3 (WFC3), and, in parallel, the Wide Field Channel (WFC) of the Advanced Camera for Surveys (ACS). See log of the observations (from 2011 Oct 03 to 2013 Sep 17) in table 1. (2 data files).
Orientation Modeling for Amateur Cameras by Matching Image Line Features and Building Vector Data
NASA Astrophysics Data System (ADS)
Hung, C. H.; Chang, W. C.; Chen, L. C.
2016-06-01
With the popularity of geospatial applications, database updating is getting important due to the environmental changes over time. Imagery provides a lower cost and efficient way to update the database. Three dimensional objects can be measured by space intersection using conjugate image points and orientation parameters of cameras. However, precise orientation parameters of light amateur cameras are not always available due to their costliness and heaviness of precision GPS and IMU. To automatize data updating, the correspondence of object vector data and image may be built to improve the accuracy of direct georeferencing. This study contains four major parts, (1) back-projection of object vector data, (2) extraction of image feature lines, (3) object-image feature line matching, and (4) line-based orientation modeling. In order to construct the correspondence of features between an image and a building model, the building vector features were back-projected onto the image using the initial camera orientation from GPS and IMU. Image line features were extracted from the imagery. Afterwards, the matching procedure was done by assessing the similarity between the extracted image features and the back-projected ones. Then, the fourth part utilized line features in orientation modeling. The line-based orientation modeling was performed by the integration of line parametric equations into collinearity condition equations. The experiment data included images with 0.06 m resolution acquired by Canon EOS Mark 5D II camera on a Microdrones MD4-1000 UAV. Experimental results indicate that 2.1 pixel accuracy may be reached, which is equivalent to 0.12 m in the object space.
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.
Time for a Change; Spirit's View on Sol 1843 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11973 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11973 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, full-circle view of the rover's surroundings during the 1,843rd Martian day, or sol, of Spirit's surface mission (March 10, 2009). South is in the middle. North is at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 36 centimeters downhill earlier on Sol 1854, but had not been able to get free of ruts in soft material that had become an obstacle to getting around the northeastern corner of the low plateau called 'Home Plate.' The Sol 1854 drive, following two others in the preceding four sols that also achieved little progress in the soft ground, prompted the rover team to switch to a plan of getting around Home Plate counterclockwise, instead of clockwise. The drive direction in subsequent sols was westward past the northern edge of Home Plate. This view is presented as a cylindrical-perspective projection with geometric seam correction.View Ahead After Spirit's Sol 1861 Drive (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11977 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11977 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images combined into this stereo, 210-degree view of the rover's surroundings during the 1,861st to 1,863rd Martian days, or sols, of Spirit's surface mission (March 28 to 30, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The center of the scene is toward the south-southwest. East is on the left. West-northwest is on the right. The rover had driven 22.7 meters (74 feet) southwestward on Sol 1861 before beginning to take the frames in this view. The drive brought Spirit past the northwestern corner of Home Plate. In this view, the western edge of Home Plate is on the portion of the horizon farthest to the left. A mound in middle distance near the center of the view is called 'Tsiolkovsky' and is about 40 meters (about 130 feet) from the rover's position. This view is presented as a cylindrical-perspective projection with geometric seam correction.Hollywood on tobacco: how the entertainment industry understands tobacco portrayal
Shields, D.; Carol, J.; Balbach, E.; McGee, S.
1999-01-01
OBJECTIVE—To determine how people in the California-based entertainment industry think about the portrayal of tobacco use in movies and on television. Specifically, to explore who decides when to include tobacco in a project; how that decision is made; what issues are considered; what messages are intended; whether and how the issue of secondhand smoke is considered; and what advocacy methods might be useful in influencing future decisions about tobacco portrayal. DESIGN—Qualitative in-depth interviews of entertainment industry personnel,with a semi-structured interview protocol to guide the interview. SUBJECTS—54 subjects drawn from a convenience sample of writers, actors, directors, producers, studio executives, and others involved in the film industry. RESULTS—Hollywood is heterogeneous with varying perspectives on rates of tobacco use portrayal; intentionality of the decision to use and the necessity to portray tobacco use; and its degree of acceptance of responsibility for influencing societal smoking. Tobacco depiction may originate with the writer, actor, or director and is included most frequently to elucidate character or portray reality. On-camera smoking is influenced by actors' off-camera tobacco use. CONCLUSIONS—The research presented can help advocates better understand the norms and values of those working within the entertainment industry and thereby assist them in creating more effective change strategies. Keywords: films; movies; television; tobacco use PMID:10629243
Low-cost uncooled VOx infrared camera development
NASA Astrophysics Data System (ADS)
Li, Chuan; Han, C. J.; Skidmore, George D.; Cook, Grady; Kubala, Kenny; Bates, Robert; Temple, Dorota; Lannon, John; Hilton, Allan; Glukh, Konstantin; Hardy, Busbee
2013-06-01
The DRS Tamarisk® 320 camera, introduced in 2011, is a low cost commercial camera based on the 17 µm pixel pitch 320×240 VOx microbolometer technology. A higher resolution 17 µm pixel pitch 640×480 Tamarisk®640 has also been developed and is now in production serving the commercial markets. Recently, under the DARPA sponsored Low Cost Thermal Imager-Manufacturing (LCTI-M) program and internal project, DRS is leading a team of industrial experts from FiveFocal, RTI International and MEMSCAP to develop a small form factor uncooled infrared camera for the military and commercial markets. The objective of the DARPA LCTI-M program is to develop a low SWaP camera (<3.5 cm3 in volume and <500 mW in power consumption) that costs less than US $500 based on a 10,000 units per month production rate. To meet this challenge, DRS is developing several innovative technologies including a small pixel pitch 640×512 VOx uncooled detector, an advanced digital ROIC and low power miniature camera electronics. In addition, DRS and its partners are developing innovative manufacturing processes to reduce production cycle time and costs including wafer scale optic and vacuum packaging manufacturing and a 3-dimensional integrated camera assembly. This paper provides an overview of the DRS Tamarisk® project and LCTI-M related uncooled technology development activities. Highlights of recent progress and challenges will also be discussed. It should be noted that BAE Systems and Raytheon Vision Systems are also participants of the DARPA LCTI-M program.
Calibration Procedures in Mid Format Camera Setups
NASA Astrophysics Data System (ADS)
Pivnicka, F.; Kemper, G.; Geissler, S.
2012-07-01
A growing number of mid-format cameras are used for aerial surveying projects. To achieve a reliable and geometrically precise result also in the photogrammetric workflow, awareness on the sensitive parts is important. The use of direct referencing systems (GPS/IMU), the mounting on a stabilizing camera platform and the specific values of the mid format camera make a professional setup with various calibration and misalignment operations necessary. An important part is to have a proper camera calibration. Using aerial images over a well designed test field with 3D structures and/or different flight altitudes enable the determination of calibration values in Bingo software. It will be demonstrated how such a calibration can be performed. The direct referencing device must be mounted in a solid and reliable way to the camera. Beside the mechanical work especially in mounting the camera beside the IMU, 2 lever arms have to be measured in mm accuracy. Important are the lever arms from the GPS Antenna to the IMU's calibrated centre and also the lever arm from the IMU centre to the Camera projection centre. In fact, the measurement with a total station is not a difficult task but the definition of the right centres and the need for using rotation matrices can cause serious accuracy problems. The benefit of small and medium format cameras is that also smaller aircrafts can be used. Like that, a gyro bases stabilized platform is recommended. This causes, that the IMU must be mounted beside the camera on the stabilizer. The advantage is, that the IMU can be used to control the platform, the problematic thing is, that the IMU to GPS antenna lever arm is floating. In fact we have to deal with an additional data stream, the values of the movement of the stabiliser to correct the floating lever arm distances. If the post-processing of the GPS-IMU data by taking the floating levers into account, delivers an expected result, the lever arms between IMU and camera can be applied. However, there is a misalignment (bore side angle) that must be evaluated by photogrammetric process using advanced tools e.g. in Bingo. Once, all these parameters have been determined, the system is capable for projects without or with only a few ground control points. But which effect has the photogrammetric process when directly applying the achieved direct orientation values compared with an AT based on a proper tiepoint matching? The paper aims to show the steps to be done by potential users and gives a kind of quality estimation about the importance and quality influence of the various calibration and adjustment steps.
NASA Technical Reports Server (NTRS)
Graff, Paige Valderrama; Baker, Marshalyn (Editor); Graff, Trevor (Editor); Lindgren, Charlie (Editor); Mailhot, Michele (Editor); McCollum, Tim (Editor); Runco, Susan (Editor); Stefanov, William (Editor); Willis, Kim (Editor)
2010-01-01
Scientists from the Image Science and Analysis Laboratory (ISAL) at NASA's Johnson Space Center (JSC) work with astronauts onboard the International Space Station (ISS) who take images of Earth. Astronaut photographs, sometimes referred to as Crew Earth Observations, are taken using hand-held digital cameras onboard the ISS. These digital images allow scientists to study our Earth from the unique perspective of space. Astronauts have taken images of Earth since the 1960s. There is a database of over 900,000 astronaut photographs available at http://eol.jsc.nasa.gov . Images are requested by ISAL scientists at JSC and astronauts in space personally frame and acquire them from the Destiny Laboratory or other windows in the ISS. By having astronauts take images, they can specifically frame them according to a given request and need. For example, they can choose to use different lenses to vary the amount of area (field of view) an image will cover. Images can be taken at different times of the day which allows different lighting conditions to bring out or highlight certain features. The viewing angle at which an image is acquired can also be varied to show the same area from different perspectives. Pointing the camera straight down gives you a nadir shot. Pointing the camera at an angle to get a view across an area would be considered an oblique shot. Being able to change these variables makes astronaut photographs a unique and useful data set. Astronaut photographs are taken from the ISS from altitudes of 300 - 400 km (185 to 250 miles). One of the current cameras being used, the Nikon D3X digital camera, can take images using a 50, 100, 250, 400 or 800mm lens. These different lenses allow for a wider or narrower field of view. The higher the focal length (800mm for example) the narrower the field of view (less area will be covered). Higher focal lengths also show greater detail of the area on the surface being imaged. Scientists from the Image Science and Analysis Laboratory (ISAL) at NASA s Johnson Space Center (JSC) work with astronauts onboard the International Space Station (ISS) who take images of Earth. Astronaut photographs, sometimes referred to as Crew Earth Observations, are taken using hand-held digital cameras onboard the ISS. These digital images allow scientists to study our Earth from the unique perspective of space. Astronauts have taken images of Earth since the 1960s. There is a database of over 900,000 astronaut photographs available at http://eol.jsc.nasa.gov . Images are requested by ISAL scientists at JSC and astronauts in space personally frame and acquire them from the Destiny Laboratory or other windows in the ISS. By having astronauts take images, they can specifically frame them according to a given request and need. For example, they can choose to use different lenses to vary the amount of area (field of view) an image will cover. Images can be taken at different times of the day which allows different lighting conditions to bring out or highlight certain features. The viewing angle at which an image is acquired can also be varied to show the same area from different perspectives. Pointing the camera straight down gives you a nadir shot. Pointing the camera at an angle to get a view across an area would be considered an oblique shot. Being able to change these variables makes astronaut photographs a unique and useful data set. Astronaut photographs are taken from the ISS from altitudes of 300 - 400 km (approx.185 to 250 miles). One of the current cameras being used, the Nikon D3X digital camera, can take images using a 50, 100, 250, 400 or 800mm lens. These different lenses allow for a wider or narrower field of view. The higher the focal length (800mm for example) the narrower the field of view (less area will be covered). Higher focal lengths also show greater detail of the area on the surface being imaged. There are four major systems or spheres of Earth. They are: Atmosphere, Biosphere, Hydrosphe, and Litho/Geosphere.
STS-31 crew activity on the middeck of the Earth-orbiting Discovery, OV-103
1990-04-29
STS031-05-002 (24-29 April 1990) --- A 35mm camera with a "fish eye" lens captured this high angle image on Discovery's middeck. Astronaut Kathryn D. Sullivan works with the IMAX camera in foreground, while Astronaut Steven A. Hawley consults a checklist in corner. An Arriflex motion picture camera records student ion arc experiment in apparatus mounted on stowage locker. The experiment was the project of Gregory S. Peterson, currently a student at Utah State University.
Performance of the prototype LaBr3 spectrometer developed for the JET gamma-ray camera upgrade.
Rigamonti, D; Muraro, A; Nocente, M; Perseo, V; Boltruczyk, G; Fernandes, A; Figueiredo, J; Giacomelli, L; Gorini, G; Gosk, M; Kiptily, V; Korolczuk, S; Mianowski, S; Murari, A; Pereira, R C; Cippo, E P; Zychor, I; Tardocchi, M
2016-11-01
In this work, we describe the solution developed by the gamma ray camera upgrade enhancement project to improve the spectroscopic properties of the existing JET γ-ray camera. Aim of the project is to enable gamma-ray spectroscopy in JET deuterium-tritium plasmas. A dedicated pilot spectrometer based on a LaBr 3 crystal coupled to a silicon photo-multiplier has been developed. A proper pole zero cancellation network able to shorten the output signal to a length of 120 ns has been implemented allowing for spectroscopy at MHz count rates. The system has been characterized in the laboratory and shows an energy resolution of 5.5% at E γ = 0.662 MeV, which extrapolates favorably in the energy range of interest for gamma-ray emission from fast ions in fusion plasmas.
What Juno will see at Jupiter South Pole Simulation
2011-08-03
This simulated view of the south pole of Jupiter illustrates the unique perspective of NASA Juno mission. Juno polar orbit will allow its camera, called JunoCam, to image Jupiter clouds from a vantage point never accessed by other spacecraft.
Conical Perspective Image of an Architectural Object Close to Human Perception
NASA Astrophysics Data System (ADS)
Dzwierzynska, Jolanta
2017-10-01
The aim of the study is to develop a method of computer aided constructing conical perspective of an architectural object, which is close to human perception. The conical perspective considered in the paper is a central projection onto a projection surface being a conical rotary surface or a fragment of it. Whereas, the centre of projection is a stationary point or a point moving on a circular path. The graphical mapping results of the perspective representation is realized directly on an unrolled flat projection surface. The projective relation between a range of points on a line and the perspective image of the same range of points received on a cylindrical projection surface permitted to derive formulas for drawing perspective. Next, the analytical algorithms for drawing perspective image of a straight line passing through any two points were formulated. It enabled drawing a perspective wireframe image of a given 3D object. The use of the moving view point as well as the application of the changeable base elements of perspective as the variables in the algorithms enable drawing conical perspective from different viewing positions. Due to this fact, the perspective drawing method is universal. The algorithms are formulated and tested in Mathcad Professional software, but can be implemented in AutoCAD and majority of computer graphical packages, which makes drawing a perspective image more efficient and easier. The presented conical perspective representation, and the convenient method of its mapping directly on the flat unrolled surface can find application for numerous advertisement and art presentations.
Suzuki, Daichi G; Murakami, Yasunori; Escriva, Hector; Wada, Hiroshi
2015-02-01
Vertebrates are equipped with so-called camera eyes, which provide them with image-forming vision. Vertebrate image-forming vision evolved independently from that of other animals and is regarded as a key innovation for enhancing predatory ability and ecological success. Evolutionary changes in the neural circuits, particularly the visual center, were central for the acquisition of image-forming vision. However, the evolutionary steps, from protochordates to jaw-less primitive vertebrates and then to jawed vertebrates, remain largely unknown. To bridge this gap, we present the detailed development of retinofugal projections in the lamprey, the neuroarchitecture in amphioxus, and the brain patterning in both animals. Both the lateral eye in larval lamprey and the frontal eye in amphioxus project to a light-detecting visual center in the caudal prosencephalic region marked by Pax6, which possibly represents the ancestral state of the chordate visual system. Our results indicate that the visual system of the larval lamprey represents an evolutionarily primitive state, forming a link from protochordates to vertebrates and providing a new perspective of brain evolution based on developmental mechanisms and neural functions. © 2014 Wiley Periodicals, Inc.
Allé, Mélissa C; Manning, Liliann; Potheegadoo, Jevita; Coutelle, Romain; Danion, Jean-Marie; Berna, Fabrice
2017-03-01
Autobiographical memory, central in human cognition and every day functioning, enables past experienced events to be remembered. A variety of disorders affecting autobiographical memory are characterized by the difficulty of retrieving specific detailed memories of past personal events. Owing to the impact of autobiographical memory impairment on patients' daily life, it is necessary to better understand these deficits and develop relevant methods to improve autobiographical memory. The primary objective of the present systematic PRISMA review was to give an overview of the first empirical evidence of the potential of wearable cameras in autobiographical memory investigation in remediating autobiographical memory impairments. The peer-reviewed literature published since 2004 on the usefulness of wearable cameras in research protocols was explored in 3 databases (PUBMED, PsycINFO, and Google Scholar). Twenty-eight published studies that used a protocol involving wearable camera, either to explore wearable camera functioning and impact on daily life, or to investigate autobiographical memory processing or remediate autobiographical memory impairment, were included. This review analyzed the potential of wearable cameras for 1) investigating autobiographical memory processes in healthy volunteers without memory impairment and in clinical populations, and 2) remediating autobiographical memory in patients with various kinds of memory disorder. Mechanisms to account for the efficacy of wearable cameras are also discussed. The review concludes by discussing certain limitations inherent to using cameras, and new research perspectives. Finally, ethical issues raised by this new technology are considered.
Digital Camera with Apparatus for Authentication of Images Produced from an Image File
NASA Technical Reports Server (NTRS)
Friedman, Gary L. (Inventor)
1996-01-01
A digital camera equipped with a processor for authentication of images produced from an image file taken by the digital camera is provided. The digital camera processor has embedded therein a private key unique to it, and the camera housing has a public key that is so uniquely related to the private key that digital data encrypted with the private key may be decrypted using the public key. The digital camera processor comprises means for calculating a hash of the image file using a predetermined algorithm, and second means for encrypting the image hash with the private key, thereby producing a digital signature. The image file and the digital signature are stored in suitable recording means so they will be available together. Apparatus for authenticating the image file as being free of any alteration uses the public key for decrypting the digital signature, thereby deriving a secure image hash identical to the image hash produced by the digital camera and used to produce the digital signature. The authenticating apparatus calculates from the image file an image hash using the same algorithm as before. By comparing this last image hash with the secure image hash, authenticity of the image file is determined if they match. Other techniques to address time-honored methods of deception, such as attaching false captions or inducing forced perspectives, are included.
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.
Phoenix Lander on Mars with Surrounding Terrain, Vertical Projection
NASA Technical Reports Server (NTRS)
2008-01-01
This view is a vertical projection that combines more than 500 exposures taken by the Surface Stereo Imager camera on NASA's Mars Phoenix Lander and projects them as if looking down from above. The black circle on the spacecraft is where the camera itself is mounted on the lander, out of view in images taken by the camera. North is toward the top of the image. The height of the lander's meteorology mast, extending toward the southwest, appears exaggerated because that mast is taller than the camera mast. This view in approximately true color covers an area about 30 meters by 30 meters (about 100 feet by 100 feet). The landing site is at 68.22 degrees north latitude, 234.25 degrees east longitude on Mars. The ground surface around the lander has polygonal patterning similar to patterns in permafrost areas on Earth. This view comprises more than 100 different Stereo Surface Imager pointings, with images taken through three different filters at each pointing. The images were taken throughout the period from the 13th Martian day, or sol, after landing to the 47th sol (June 5 through July 12, 2008). The lander's Robotic Arm is cut off in this mosaic view because component images were taken when the arm was out of the frame. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.ERIC Educational Resources Information Center
Mick, Carola
2011-01-01
This article presents first results of an ethnographic research project in a Luxembourgish primary school that accompanied the development of a school project by children from the fifth grade. Analysing the data children themselves collected with Kodak Zi8 cameras in order to document their project activities, it investigates their possibilities…
Use of camera drive in stereoscopic display of learning contents of introductory physics
NASA Astrophysics Data System (ADS)
Matsuura, Shu
2011-03-01
Simple 3D physics simulations with stereoscopic display were created for a part of introductory physics e-Learning. First, cameras to see the 3D world can be made controllable by the user. This enabled to observe the system and motions of objects from any position in the 3D world. Second, cameras were made attachable to one of the moving object in the simulation so as to observe the relative motion of other objects. By this option, it was found that users perceive the velocity and acceleration more sensibly on stereoscopic display than on non-stereoscopic 3D display. Simulations were made using Adobe Flash ActionScript, and Papervison 3D library was used to render the 3D models in the flash web pages. To display the stereogram, two viewports from virtual cameras were displayed in parallel in the same web page. For observation of stereogram, the images of two viewports were superimposed by using 3D stereogram projection box (T&TS CO., LTD.), and projected on an 80-inch screen. The virtual cameras were controlled by keyboard and also by Nintendo Wii remote controller buttons. In conclusion, stereoscopic display offers learners more opportunities to play with the simulated models, and to perceive the characteristics of motion better.
1995-12-20
STS074-361-035 (12-20 Nov 1995) --- This medium close-up view centers on the IMAX Cargo Bay Camera (ICBC) and its associated IMAX Camera Container Equipment (ICCE) at its position in the cargo bay of the Earth-orbiting Space Shuttle Atlantis. With its own ?space suit? or protective covering to protect it from the rigors of space, this version of the IMAX was able to record scenes not accessible with the in-cabin cameras. For docking and undocking activities involving Russia?s Mir Space Station and the Space Shuttle Atlantis, the camera joined a variety of in-cabin camera hardware in recording the historical events. IMAX?s secondary objectives were to film Earth views. The IMAX project is a collaboration between NASA, the Smithsonian Institution?s National Air and Space Museum (NASM), IMAX Systems Corporation, and the Lockheed Corporation to document significant space activities and promote NASA?s educational goals using the IMAX film medium.
Using a Smartphone Camera for Nanosatellite Attitude Determination
NASA Astrophysics Data System (ADS)
Shimmin, R.
2014-09-01
The PhoneSat project at NASA Ames Research Center has repeatedly flown a commercial cellphone in space. As this project continues, additional utility is being extracted from the cell phone hardware to enable more complex missions. The camera in particular shows great potential as an instrument for position and attitude determination, but this requires complex image processing. This paper outlines progress towards that image processing capability. Initial tests on a small collection of sample images have demonstrated the determination of a Moon vector from an image by automatic thresholding and centroiding, allowing the calibration of existing attitude control systems. Work has been undertaken on a further set of sample images towards horizon detection using a variety of techniques including thresholding, edge detection, applying a Hough transform, and circle fitting. Ultimately it is hoped this will allow calculation of an Earth vector for attitude determination and an approximate altitude. A quick discussion of work towards using the camera as a star tracker is then presented, followed by an introduction to further applications of the camera on space missions.
RGB-D SLAM Based on Extended Bundle Adjustment with 2D and 3D Information
Di, Kaichang; Zhao, Qiang; Wan, Wenhui; Wang, Yexin; Gao, Yunjun
2016-01-01
In the study of SLAM problem using an RGB-D camera, depth information and visual information as two types of primary measurement data are rarely tightly coupled during refinement of camera pose estimation. In this paper, a new method of RGB-D camera SLAM is proposed based on extended bundle adjustment with integrated 2D and 3D information on the basis of a new projection model. First, the geometric relationship between the image plane coordinates and the depth values is constructed through RGB-D camera calibration. Then, 2D and 3D feature points are automatically extracted and matched between consecutive frames to build a continuous image network. Finally, extended bundle adjustment based on the new projection model, which takes both image and depth measurements into consideration, is applied to the image network for high-precision pose estimation. Field experiments show that the proposed method has a notably better performance than the traditional method, and the experimental results demonstrate the effectiveness of the proposed method in improving localization accuracy. PMID:27529256
NASA Astrophysics Data System (ADS)
Kolstein, M.; De Lorenzo, G.; Mikhaylova, E.; Chmeissani, M.; Ariño, G.; Calderón, Y.; Ozsahin, I.; Uzun, D.
2013-04-01
The Voxel Imaging PET (VIP) Pathfinder project intends to show the advantages of using pixelated solid-state technology for nuclear medicine applications. It proposes designs for Positron Emission Tomography (PET), Positron Emission Mammography (PEM) and Compton gamma camera detectors with a large number of signal channels (of the order of 106). For PET scanners, conventional algorithms like Filtered Back-Projection (FBP) and Ordered Subset Expectation Maximization (OSEM) are straightforward to use and give good results. However, FBP presents difficulties for detectors with limited angular coverage like PEM and Compton gamma cameras, whereas OSEM has an impractically large time and memory consumption for a Compton gamma camera with a large number of channels. In this article, the Origin Ensemble (OE) algorithm is evaluated as an alternative algorithm for image reconstruction. Monte Carlo simulations of the PET design are used to compare the performance of OE, FBP and OSEM in terms of the bias, variance and average mean squared error (MSE) image quality metrics. For the PEM and Compton camera designs, results obtained with OE are presented.
Projection Mapping User Interface for Disabled People
Simutis, Rimvydas; Maskeliūnas, Rytis
2018-01-01
Difficulty in communicating is one of the key challenges for people suffering from severe motor and speech disabilities. Often such person can communicate and interact with the environment only using assistive technologies. This paper presents a multifunctional user interface designed to improve communication efficiency and person independence. The main component of this interface is a projection mapping technique used to highlight objects in the environment. Projection mapping makes it possible to create a natural augmented reality information presentation method. The user interface combines a depth sensor and a projector to create camera-projector system. We provide a detailed description of camera-projector system calibration procedure. The described system performs tabletop object detection and automatic projection mapping. Multiple user input modalities have been integrated into the multifunctional user interface. Such system can be adapted to the needs of people with various disabilities. PMID:29686827
Projection Mapping User Interface for Disabled People.
Gelšvartas, Julius; Simutis, Rimvydas; Maskeliūnas, Rytis
2018-01-01
Difficulty in communicating is one of the key challenges for people suffering from severe motor and speech disabilities. Often such person can communicate and interact with the environment only using assistive technologies. This paper presents a multifunctional user interface designed to improve communication efficiency and person independence. The main component of this interface is a projection mapping technique used to highlight objects in the environment. Projection mapping makes it possible to create a natural augmented reality information presentation method. The user interface combines a depth sensor and a projector to create camera-projector system. We provide a detailed description of camera-projector system calibration procedure. The described system performs tabletop object detection and automatic projection mapping. Multiple user input modalities have been integrated into the multifunctional user interface. Such system can be adapted to the needs of people with various disabilities.
Concept of a photon-counting camera based on a diffraction-addressed Gray-code mask
NASA Astrophysics Data System (ADS)
Morel, Sébastien
2004-09-01
A new concept of photon counting camera for fast and low-light-level imaging applications is introduced. The possible spectrum covered by this camera ranges from visible light to gamma rays, depending on the device used to transform an incoming photon into a burst of visible photons (photo-event spot) localized in an (x,y) image plane. It is actually an evolution of the existing "PAPA" (Precision Analog Photon Address) Camera that was designed for visible photons. This improvement comes from a simplified optics. The new camera transforms, by diffraction, each photo-event spot from an image intensifier or a scintillator into a cross-shaped pattern, which is projected onto a specific Gray code mask. The photo-event position is then extracted from the signal given by an array of avalanche photodiodes (or photomultiplier tubes, alternatively) downstream of the mask. After a detailed explanation of this camera concept that we have called "DIAMICON" (DIffraction Addressed Mask ICONographer), we briefly discuss about technical solutions to build such a camera.
NASA Astrophysics Data System (ADS)
Ou, Yangwei; Zhang, Hongbo; Li, Bin
2018-04-01
The purpose of this paper is to show that absolute orbit determination can be achieved based on spacecraft formation. The relative position vectors expressed in the inertial frame are used as measurements. In this scheme, the optical camera is applied to measure the relative line-of-sight (LOS) angles, i.e., the azimuth and elevation. The LIDAR (Light radio Detecting And Ranging) or radar is used to measure the range and we assume that high-accuracy inertial attitude is available. When more deputies are included in the formation, the formation configuration is optimized from the perspective of the Fisher information theory. Considering the limitation on the field of view (FOV) of cameras, the visibility of spacecraft and the installation of cameras are investigated. In simulations, an extended Kalman filter (EKF) is used to estimate the position and velocity. The results show that the navigation accuracy can be enhanced by using more deputies and the installation of cameras significantly affects the navigation performance.
NASA Astrophysics Data System (ADS)
Feng, Zhixin
2018-02-01
Projector calibration is crucial for a camera-projector three-dimensional (3-D) structured light measurement system, which has one camera and one projector. In this paper, a novel projector calibration method is proposed based on digital image correlation. In the method, the projector is viewed as an inverse camera, and a plane calibration board with feature points is used to calibrate the projector. During the calibration processing, a random speckle pattern is projected onto the calibration board with different orientations to establish the correspondences between projector images and camera images. Thereby, dataset for projector calibration are generated. Then the projector can be calibrated using a well-established camera calibration algorithm. The experiment results confirm that the proposed method is accurate and reliable for projector calibration.
Camera calibration for multidirectional flame chemiluminescence tomography
NASA Astrophysics Data System (ADS)
Wang, Jia; Zhang, Weiguang; Zhang, Yuhong; Yu, Xun
2017-04-01
Flame chemiluminescence tomography (FCT), which combines computerized tomography theory and multidirectional chemiluminescence emission measurements, can realize instantaneous three-dimensional (3-D) diagnostics for flames with high spatial and temporal resolutions. One critical step of FCT is to record the projections by multiple cameras from different view angles. For high accuracy reconstructions, it requires that extrinsic parameters (the positions and orientations) and intrinsic parameters (especially the image distances) of cameras be accurately calibrated first. Taking the focus effect of the camera into account, a modified camera calibration method was presented for FCT, and a 3-D calibration pattern was designed to solve the parameters. The precision of the method was evaluated by reprojections of feature points to cameras with the calibration results. The maximum root mean square error of the feature points' position is 1.42 pixels and 0.0064 mm for the image distance. An FCT system with 12 cameras was calibrated by the proposed method and the 3-D CH* intensity of a propane flame was measured. The results showed that the FCT system provides reasonable reconstruction accuracy using the camera's calibration results.
Calibration Image of Earth by Mars Color Imager
NASA Technical Reports Server (NTRS)
2005-01-01
Three days after the Mars Reconnaissance Orbiter's Aug. 12, 2005, launch, the NASA spacecraft was pointed toward Earth and the Mars Color Imager camera was powered up to acquire a suite of color and ultraviolet images of Earth and the Moon. When it gets to Mars, the Mars Color Imager's main objective will be to obtain daily global color and ultraviolet images of the planet to observe martian meteorology by documenting the occurrence of dust storms, clouds, and ozone. This camera will also observe how the martian surface changes over time, including changes in frost patterns and surface brightness caused by dust storms and dust devils. The purpose of acquiring an image of Earth and the Moon just three days after launch was to help the Mars Color Imager science team obtain a measure, in space, of the instrument's sensitivity, as well as to check that no contamination occurred on the camera during launch. Prior to launch, the team determined that, three days out from Earth, the planet would only be about 4.77 pixels across, and the Moon would be less than one pixel in size, as seen from the Mars Color Imager's wide-angle perspective. If the team waited any longer than three days to test the camera's performance in space, Earth would be too small to obtain meaningful results. The images were acquired by turning Mars Reconnaissance Orbiter toward Earth, then slewing the spacecraft so that the Earth and Moon would pass before each of the five color and two ultraviolet filters of the Mars Color Imager. The distance to Earth was about 1,170,000 kilometers (about 727,000 miles). This image shows a color composite view of Mars Color Imager's image of Earth. As expected, it covers only five pixels. This color view has been enlarged five times. The Sun was illuminating our planet from the left, thus only one quarter of Earth is seen from this perspective. North America was in daylight and facing toward the camera at the time the picture was taken; the data from the camera were being transmitted in real time to the Deep Space Network antennas in Goldstone, California.IET. Aerial view of project, 95 percent complete. Camera facing ...
IET. Aerial view of project, 95 percent complete. Camera facing east. Left to right: stack, duct, mobile test cell building (TAN-624), four-rail track, dolly. Retaining wall between mobile test building and shielded control building (TAN-620) just beyond. North of control building are tank building (TAN-627) and fuel-transfer pump building (TAN-625). Guard house at upper right along exclusion fence. Construction vehicles and temporary warehouse in view near guard house. Date: June 6, 1955. INEEL negative no. 55-1462 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID
A system for simulating aerial or orbital TV observations of geographic patterns
NASA Technical Reports Server (NTRS)
Latham, J. P.
1972-01-01
A system which simulates observation of the earth surface by aerial or orbiting television devices has been developed. By projecting color slides of photographs taken by aircraft and orbiting sensors upon a rear screen system, and altering scale of projected image, screen position, or TV camera position, it is possible to simulate alternatives of altitude, or optical systems. By altering scan line patterns in COHU 3200 series camera from 525 to 945 scan lines, it is possible to study implications of scan line resolution upon the detection and analysis of geographic patterns observed by orbiting TV systems.
Non-destructive 3D shape measurement of transparent and black objects with thermal fringes
NASA Astrophysics Data System (ADS)
Brahm, Anika; Rößler, Conrad; Dietrich, Patrick; Heist, Stefan; Kühmstedt, Peter; Notni, Gunther
2016-05-01
Fringe projection is a well-established optical method for the non-destructive contactless three-dimensional (3D) measurement of object surfaces. Typically, fringe sequences in the visible wavelength range (VIS) are projected onto the surfaces of objects to be measured and are observed by two cameras in a stereo vision setup. The reconstruction is done by finding corresponding pixels in both cameras followed by triangulation. Problems can occur if the properties of some materials disturb the measurements. If the objects are transparent, translucent, reflective, or strongly absorbing in the VIS range, the projected patterns cannot be recorded properly. To overcome these challenges, we present a new alternative approach in the infrared (IR) region of the electromagnetic spectrum. For this purpose, two long-wavelength infrared (LWIR) cameras (7.5 - 13 μm) are used to detect the emitted heat radiation from surfaces which is induced by a pattern projection unit driven by a CO2 laser (10.6 μm). Thus, materials like glass or black objects, e.g. carbon fiber materials, can be measured non-destructively without the need of any additional paintings. We will demonstrate the basic principles of this heat pattern approach and show two types of 3D systems based on a freeform mirror and a GOBO wheel (GOes Before Optics) projector unit.
Enabling technologies for space exploration systems: The STEPS project results and perspectives
NASA Astrophysics Data System (ADS)
Messidoro, Piero; Perino, Maria Antonietta; Boggiatto, Dario
2013-05-01
The project STEPS (Sistemi e Tecnologie per l'EsPlorazione Spaziale) is a joint development of technologies and systems for Space Exploration supported by Regione Piemonte, the European Regional Development Fund (E.R.D.F.) 2007-2013, Thales Alenia Space Italia (TAS-I), SMEs, Universities and public Research Centres belonging to the network "Comitato Distretto Aerospaziale del Piemonte" the Piedmont Aerospace District (PAD) in Italy. The project first part terminated in May 2012 with a final demonstration event that summarizes the technological results of research activities carried-out during a period the three years and half. The project developed virtual and hardware demonstrators for a range of technologies for the descent, soft landing and surface mobility of robotic and manned equipment for Moon and Mars exploration. The two key hardware demonstrators—a Mars Lander and a Lunar Rover—fit in a context of international cooperation for the exploration of Moon and Mars, as envisaged by Space Agencies worldwide. The STEPS project included also the development and utilization of a system of laboratories equipped for technology validation, teleoperations, concurrent design environments, and virtual reality simulation of the Exploration Systems in typical Moon and Mars environments. This paper presents the reached results in several technology domains like: vision-based GNC for the last portion of Mars Entry, Descent and Landing sequence, Hazard avoidance and complete spacecraft autonomy; Autonomous Rover Navigation, based on the determination of the terrain morphology by a stereo camera; Mobility and Mechanisms providing an Integrated Ground Mobility System, Rendezvous and Docking equipment, and protection from Environment effects; innovative Structures such as Inflatable, Smart and Multifunction Structures, an Active Shock Absorber for safe landing, balance restoring and walking; Composite materials Modelling and Monitoring; Human-machine interface features of a predictive Command and Control System; Energy Management systems based on Regenerative Fuel Cells; aerothermodynamic solutions for Atmospheric Re-entry of Commercial Transportation Systems; novel Design and Development Tools, such as a Rover S/W simulator and prototypes of the DEM viewer and of a S/W Rock Creator/visualizator. The paper also provides perspectives on the proposed STEPS 2 project that will likely continue the development of a subset of the above technologies in view of their possible in-flight validation within next five years.
Flash LIDAR Emulator for HIL Simulation
NASA Technical Reports Server (NTRS)
Brewster, Paul F.
2010-01-01
NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) project is building a system for detecting hazards and automatically landing controlled vehicles safely anywhere on the Moon. The Flash Light Detection And Ranging (LIDAR) sensor is used to create on-the-fly a 3D map of the unknown terrain for hazard detection. As part of the ALHAT project, a hardware-in-the-loop (HIL) simulation testbed was developed to test the data processing, guidance, and navigation algorithms in real-time to prove their feasibility for flight. Replacing the Flash LIDAR camera with an emulator in the testbed provided a cheaper, safer, more feasible way to test the algorithms in a controlled environment. This emulator must have the same hardware interfaces as the LIDAR camera, have the same performance characteristics, and produce images similar in quality to the camera. This presentation describes the issues involved and the techniques used to create a real-time flash LIDAR emulator to support HIL simulation.
Performance of the prototype LaBr{sub 3} spectrometer developed for the JET gamma-ray camera upgrade
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rigamonti, D., E-mail: davide.rigamonti@mib.infn.it; Nocente, M.; Gorini, G.
2016-11-15
In this work, we describe the solution developed by the gamma ray camera upgrade enhancement project to improve the spectroscopic properties of the existing JET γ-ray camera. Aim of the project is to enable gamma-ray spectroscopy in JET deuterium-tritium plasmas. A dedicated pilot spectrometer based on a LaBr{sub 3} crystal coupled to a silicon photo-multiplier has been developed. A proper pole zero cancellation network able to shorten the output signal to a length of 120 ns has been implemented allowing for spectroscopy at MHz count rates. The system has been characterized in the laboratory and shows an energy resolution ofmore » 5.5% at E{sub γ} = 0.662 MeV, which extrapolates favorably in the energy range of interest for gamma-ray emission from fast ions in fusion plasmas.« less
C-RED One and C-RED2: SWIR high-performance cameras using Saphira e-APD and Snake InGaAs detectors
NASA Astrophysics Data System (ADS)
Gach, Jean-Luc; Feautrier, Philippe; Stadler, Eric; Clop, Fabien; Lemarchand, Stephane; Carmignani, Thomas; Wanwanscappel, Yann; Boutolleau, David
2018-02-01
After the development of the OCAM2 EMCCD fast visible camera dedicated to advanced adaptive optics wavefront sensing, First Light Imaging moved to the SWIR fast cameras with the development of the C-RED One and the C-RED 2 cameras. First Light Imaging's C-RED One infrared camera is capable of capturing up to 3500 full frames per second with a subelectron readout noise and very low background. C-RED One is based on the last version of the SAPHIRA detector developed by Leonardo UK. This breakthrough has been made possible thanks to the use of an e-APD infrared focal plane array which is a real disruptive technology in imagery. C-RED One is an autonomous system with an integrated cooling system and a vacuum regeneration system. It operates its sensor with a wide variety of read out techniques and processes video on-board thanks to an FPGA. We will show its performances and expose its main features. In addition to this project, First Light Imaging developed an InGaAs 640x512 fast camera with unprecedented performances in terms of noise, dark and readout speed based on the SNAKE SWIR detector from Sofradir. The camera was called C-RED 2. The C-RED 2 characteristics and performances will be described. The C-RED One project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement N° 673944. The C-RED 2 development is supported by the "Investments for the future" program and the Provence Alpes Côte d'Azur Region, in the frame of the CPER.
High-Speed Edge-Detecting Line Scan Smart Camera
NASA Technical Reports Server (NTRS)
Prokop, Norman F.
2012-01-01
A high-speed edge-detecting line scan smart camera was developed. The camera is designed to operate as a component in a NASA Glenn Research Center developed inlet shock detection system. The inlet shock is detected by projecting a laser sheet through the airflow. The shock within the airflow is the densest part and refracts the laser sheet the most in its vicinity, leaving a dark spot or shadowgraph. These spots show up as a dip or negative peak within the pixel intensity profile of an image of the projected laser sheet. The smart camera acquires and processes in real-time the linear image containing the shock shadowgraph and outputting the shock location. Previously a high-speed camera and personal computer would perform the image capture and processing to determine the shock location. This innovation consists of a linear image sensor, analog signal processing circuit, and a digital circuit that provides a numerical digital output of the shock or negative edge location. The smart camera is capable of capturing and processing linear images at over 1,000 frames per second. The edges are identified as numeric pixel values within the linear array of pixels, and the edge location information can be sent out from the circuit in a variety of ways, such as by using a microcontroller and onboard or external digital interface to include serial data such as RS-232/485, USB, Ethernet, or CAN BUS; parallel digital data; or an analog signal. The smart camera system can be integrated into a small package with a relatively small number of parts, reducing size and increasing reliability over the previous imaging system..
An image compression algorithm for a high-resolution digital still camera
NASA Technical Reports Server (NTRS)
Nerheim, Rosalee
1989-01-01
The Electronic Still Camera (ESC) project will provide for the capture and transmission of high-quality images without the use of film. The image quality will be superior to video and will approach the quality of 35mm film. The camera, which will have the same general shape and handling as a 35mm camera, will be able to send images to earth in near real-time. Images will be stored in computer memory (RAM) in removable cartridges readable by a computer. To save storage space, the image will be compressed and reconstructed at the time of viewing. Both lossless and loss-y image compression algorithms are studied, described, and compared.
Structural analysis of color video camera installation on tank 241AW101 (2 Volumes)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Strehlow, J.P.
1994-08-24
A video camera is planned to be installed on the radioactive storage tank 241AW101 at the DOE` s Hanford Site in Richland, Washington. The camera will occupy the 20 inch port of the Multiport Flange riser which is to be installed on riser 5B of the 241AW101 (3,5,10). The objective of the project reported herein was to perform a seismic analysis and evaluation of the structural components of the camera for a postulated Design Basis Earthquake (DBE) per the reference Structural Design Specification (SDS) document (6). The detail of supporting engineering calculations is documented in URS/Blume Calculation No. 66481-01-CA-03 (1).
3D GeoWall Analysis System for Shuttle External Tank Foreign Object Debris Events
NASA Technical Reports Server (NTRS)
Brown, Richard; Navard, Andrew; Spruce, Joseph
2010-01-01
An analytical, advanced imaging method has been developed for the initial monitoring and identification of foam debris and similar anomalies that occur post-launch in reference to the space shuttle s external tank (ET). Remote sensing technologies have been used to perform image enhancement and analysis on high-resolution, true-color images collected with the DCS 760 Kodak digital camera located in the right umbilical well of the space shuttle. Improvements to the camera, using filters, have added sharpness/definition to the image sets; however, image review/analysis of the ET has been limited by the fact that the images acquired by umbilical cameras during launch are two-dimensional, and are usually nonreferenceable between frames due to rotation translation of the ET as it falls away from the space shuttle. Use of stereo pairs of these images can enable strong visual indicators that can immediately portray depth perception of damaged areas or movement of fragments between frames is not perceivable in two-dimensional images. A stereoscopic image visualization system has been developed to allow 3D depth perception of stereo-aligned image pairs taken from in-flight umbilical and handheld digital shuttle cameras. This new system has been developed to augment and optimize existing 2D monitoring capabilities. Using this system, candidate sequential image pairs are identified for transformation into stereo viewing pairs. Image orientation is corrected using control points (similar points) between frames to place the two images in proper X-Y viewing perspective. The images are then imported into the WallView stereo viewing software package. The collected control points are used to generate a transformation equation that is used to re-project one image and effectively co-register it to the other image. The co-registered, oriented image pairs are imported into a WallView image set and are used as a 3D stereo analysis slide show. Multiple sequential image pairs can be used to allow forensic review of temporal phenomena between pairs. The observer, while wearing linear polarized glasses, is able to review image pairs in passive 3D stereo.
Operator vision aids for space teleoperation assembly and servicing
NASA Technical Reports Server (NTRS)
Brooks, Thurston L.; Ince, Ilhan; Lee, Greg
1992-01-01
This paper investigates concepts for visual operator aids required for effective telerobotic control. Operator visual aids, as defined here, mean any operational enhancement that improves man-machine control through the visual system. These concepts were derived as part of a study of vision issues for space teleoperation. Extensive literature on teleoperation, robotics, and human factors was surveyed to definitively specify appropriate requirements. This paper presents these visual aids in three general categories of camera/lighting functions, display enhancements, and operator cues. In the area of camera/lighting functions concepts are discussed for: (1) automatic end effector or task tracking; (2) novel camera designs; (3) computer-generated virtual camera views; (4) computer assisted camera/lighting placement; and (5) voice control. In the technology area of display aids, concepts are presented for: (1) zone displays, such as imminent collision or indexing limits; (2) predictive displays for temporal and spatial location; (3) stimulus-response reconciliation displays; (4) graphical display of depth cues such as 2-D symbolic depth, virtual views, and perspective depth; and (5) view enhancements through image processing and symbolic representations. Finally, operator visual cues (e.g., targets) that help identify size, distance, shape, orientation and location are discussed.
Plate refractive camera model and its applications
NASA Astrophysics Data System (ADS)
Huang, Longxiang; Zhao, Xu; Cai, Shen; Liu, Yuncai
2017-03-01
In real applications, a pinhole camera capturing objects through a planar parallel transparent plate is frequently employed. Due to the refractive effects of the plate, such an imaging system does not comply with the conventional pinhole camera model. Although the system is ubiquitous, it has not been thoroughly studied. This paper aims at presenting a simple virtual camera model, called a plate refractive camera model, which has a form similar to a pinhole camera model and can efficiently model refractions through a plate. The key idea is to employ a pixel-wise viewpoint concept to encode the refraction effects into a pixel-wise pinhole camera model. The proposed camera model realizes an efficient forward projection computation method and has some advantages in applications. First, the model can help to compute the caustic surface to represent the changes of the camera viewpoints. Second, the model has strengths in analyzing and rectifying the image caustic distortion caused by the plate refraction effects. Third, the model can be used to calibrate the camera's intrinsic parameters without removing the plate. Last but not least, the model contributes to putting forward the plate refractive triangulation methods in order to solve the plate refractive triangulation problem easily in multiviews. We verify our theory in both synthetic and real experiments.
MTR WING A, TRA604. SOUTH SIDE. CAMERA FACING NORTH. THIS ...
MTR WING A, TRA-604. SOUTH SIDE. CAMERA FACING NORTH. THIS VIEW TYPIFIES TENDENCY FOR EXPANSIONS TO TAKE THE FORM OF PROJECTIONS AND INFILL USING AVAILABLE YARD SPACES. INL NEGATIVE NO. HD47-44-3. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
REACTOR SERVICE BUILDING, TRA635. CROWDED MOCKUP AREA. CAMERA FACES EAST. ...
REACTOR SERVICE BUILDING, TRA-635. CROWDED MOCK-UP AREA. CAMERA FACES EAST. PHOTOGRAPHER'S NOTE SAYS "PICTURE REQUESTED BY IDO IN SUPPORT OF FY '58 BUILDING PROJECTS." INL NEGATIVE NO. 56-3025. R.G. Larsen, Photographer, 9/13/1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
Virtual Reality Calibration for Telerobotic Servicing
NASA Technical Reports Server (NTRS)
Kim, W.
1994-01-01
A virtual reality calibration technique of matching a virtual environment of simulated graphics models in 3-D geometry and perspective with actual camera views of the remote site task environment has been developed to enable high-fidelity preview/predictive displays with calibrated graphics overlay on live video.
Technology development: Future use of NASA's large format camera is uncertain
NASA Astrophysics Data System (ADS)
Rey, Charles F.; Fliegel, Ilene H.; Rohner, Karl A.
1990-06-01
The Large Format Camera, developed as a project to verify an engineering concept or design, has been flown only once, in 1984, on the shuttle Challenger. Since this flight, the camera has been in storage. NASA had expected that, following the camera's successful demonstration, other government agencies or private companies with special interests in photographic applications would absorb the costs for further flights using the Large Format Camera. But, because shuttle transportation costs for the Large Format Camera were estimated to be approximately $20 million (in 1987 dollars) per flight and the market for selling Large Format Camera products was limited, NASA was not successful in interesting other agencies or private companies in paying the costs. Using the camera on the space station does not appear to be a realistic alternative. Using the camera aboard NASA's Earth Resources Research (ER-2) aircraft may be feasible. Until the final disposition of the camera is decided, NASA has taken actions to protect it from environmental deterioration. The Government Accounting Office (GAO) recommends that the NASA Administrator should consider, first, using the camera on an aircraft such as the ER-2. NASA plans to solicit the private sector for expressions of interest in such use of the camera, at no cost to the government, and will be guided by the private sector response. Second, GAO recommends that if aircraft use is determined to be infeasible, NASA should consider transferring the camera to a museum, such as the National Air and Space Museum.
a Novel Approach to Camera Calibration Method for Smart Phones Under Road Environment
NASA Astrophysics Data System (ADS)
Lee, Bijun; Zhou, Jian; Ye, Maosheng; Guo, Yuan
2016-06-01
Monocular vision-based lane departure warning system has been increasingly used in advanced driver assistance systems (ADAS). By the use of the lane mark detection and identification, we proposed an automatic and efficient camera calibration method for smart phones. At first, we can detect the lane marker feature in a perspective space and calculate edges of lane markers in image sequences. Second, because of the width of lane marker and road lane is fixed under the standard structural road environment, we can automatically build a transformation matrix between perspective space and 3D space and get a local map in vehicle coordinate system. In order to verify the validity of this method, we installed a smart phone in the `Tuzhi' self-driving car of Wuhan University and recorded more than 100km image data on the road in Wuhan. According to the result, we can calculate the positions of lane markers which are accurate enough for the self-driving car to run smoothly on the road.
Descriptive and Computer Aided Drawing Perspective on an Unfolded Polyhedral Projection Surface
NASA Astrophysics Data System (ADS)
Dzwierzynska, Jolanta
2017-10-01
The aim of the herby study is to develop a method of direct and practical mapping of perspective on an unfolded prism polyhedral projection surface. The considered perspective representation is a rectilinear central projection onto a surface composed of several flat elements. In the paper two descriptive methods of drawing perspective are presented: direct and indirect. The graphical mapping of the effects of the representation is realized directly on the unfolded flat projection surface. That is due to the projective and graphical connection between points displayed on the polyhedral background and their counterparts received on the unfolded flat surface. For a significant improvement of the construction of line, analytical algorithms are formulated. They draw a perspective image of a segment of line passing through two different points determined by their coordinates in a spatial coordinate system of axis x, y, z. Compared to other perspective construction methods that use information about points, for computer vision and the computer aided design, our algorithms utilize data about lines, which are applied very often in architectural forms. Possibility of drawing lines in the considered perspective enables drawing an edge perspective image of an architectural object. The application of the changeable base elements of perspective as a horizon height and a station point location enable drawing perspective image from different viewing positions. The analytical algorithms for drawing perspective images are formulated in Mathcad software, however, they can be implemented in the majority of computer graphical packages, which can make drawing perspective more efficient and easier. The representation presented in the paper and the way of its direct mapping on the flat unfolded projection surface can find application in presentation of architectural space in advertisement and art.
Manned observations technology development, FY 1992 report
NASA Technical Reports Server (NTRS)
Israel, Steven
1992-01-01
This project evaluated the suitability of the NASA/JSC developed electronic still camera (ESC) digital image data for Earth observations from the Space Shuttle, as a first step to aid planning for Space Station Freedom. Specifically, image resolution achieved from the Space Shuttle using the current ESC system, which is configured with a Loral 15 mm x 15 mm (1024 x 1024 pixel array) CCD chip on the focal plane of a Nikon F4 camera, was compared to that of current handheld 70 mm Hasselblad 500 EL/M film cameras.
Opportunity Surroundings on 3,000th Sol, Vertical Projection
2012-09-07
This 360-degree vertical projection was assembled from images taken by the navigation camera on NASA Mars Exporation Rover Opportunity shows terrain surrounding the position where the rover spent its 3,000th Martian day.
Opportunity Surroundings on 3,000th Sol, Polar Projection
2012-09-07
This 360-degree polar projection was assembled from images taken by the navigation camera on NASA Mars Exporation Rover Opportunity shows terrain surrounding the position where the rover spent its 3,000th Martian day.
Chen, Lingling; Alexandrov, Yuriy; Kumar, Sunil; Andrews, Natalie; Dallman, Margaret J.; French, Paul M. W.; McGinty, James
2015-01-01
We describe an angular multiplexed imaging technique for 3-D in vivo cell tracking of sparse cell distributions and optical projection tomography (OPT) with superior time-lapse resolution and a significantly reduced light dose compared to volumetric time-lapse techniques. We demonstrate that using dual axis OPT, where two images are acquired simultaneously at different projection angles, can enable localization and tracking of features in 3-D with a time resolution equal to the camera frame rate. This is achieved with a 200x reduction in light dose compared to an equivalent volumetric time-lapse single camera OPT acquisition with 200 projection angles. We demonstrate the application of this technique to mapping the 3-D neutrophil migration pattern observed over ~25.5 minutes in a live 2 day post-fertilisation transgenic LysC:GFP zebrafish embryo following a tail wound. PMID:25909009
Chen, Lingling; Alexandrov, Yuriy; Kumar, Sunil; Andrews, Natalie; Dallman, Margaret J; French, Paul M W; McGinty, James
2015-04-01
We describe an angular multiplexed imaging technique for 3-D in vivo cell tracking of sparse cell distributions and optical projection tomography (OPT) with superior time-lapse resolution and a significantly reduced light dose compared to volumetric time-lapse techniques. We demonstrate that using dual axis OPT, where two images are acquired simultaneously at different projection angles, can enable localization and tracking of features in 3-D with a time resolution equal to the camera frame rate. This is achieved with a 200x reduction in light dose compared to an equivalent volumetric time-lapse single camera OPT acquisition with 200 projection angles. We demonstrate the application of this technique to mapping the 3-D neutrophil migration pattern observed over ~25.5 minutes in a live 2 day post-fertilisation transgenic LysC:GFP zebrafish embryo following a tail wound.
Video Capture of Plastic Surgery Procedures Using the GoPro HERO 3+.
Graves, Steven Nicholas; Shenaq, Deana Saleh; Langerman, Alexander J; Song, David H
2015-02-01
Significant improvements can be made in recoding surgical procedures, particularly in capturing high-quality video recordings from the surgeons' point of view. This study examined the utility of the GoPro HERO 3+ Black Edition camera for high-definition, point-of-view recordings of plastic and reconstructive surgery. The GoPro HERO 3+ Black Edition camera was head-mounted on the surgeon and oriented to the surgeon's perspective using the GoPro App. The camera was used to record 4 cases: 2 fat graft procedures and 2 breast reconstructions. During cases 1-3, an assistant remotely controlled the GoPro via the GoPro App. For case 4 the GoPro was linked to a WiFi remote, and controlled by the surgeon. Camera settings for case 1 were as follows: 1080p video resolution; 48 fps; Protune mode on; wide field of view; 16:9 aspect ratio. The lighting contrast due to the overhead lights resulted in limited washout of the video image. Camera settings were adjusted for cases 2-4 to a narrow field of view, which enabled the camera's automatic white balance to better compensate for bright lights focused on the surgical field. Cases 2-4 captured video sufficient for teaching or presentation purposes. The GoPro HERO 3+ Black Edition camera enables high-quality, cost-effective video recording of plastic and reconstructive surgery procedures. When set to a narrow field of view and automatic white balance, the camera is able to sufficiently compensate for the contrasting light environment of the operating room and capture high-resolution, detailed video.
Intraocular camera for retinal prostheses: Refractive and diffractive lens systems
NASA Astrophysics Data System (ADS)
Hauer, Michelle Christine
The focus of this thesis is on the design and analysis of refractive, diffractive, and hybrid refractive/diffractive lens systems for a miniaturized camera that can be surgically implanted in the crystalline lens sac and is designed to work in conjunction with current and future generation retinal prostheses. The development of such an intraocular camera (IOC) would eliminate the need for an external head-mounted or eyeglass-mounted camera. Placing the camera inside the eye would allow subjects to use their natural eye movements for foveation (attention) instead of more cumbersome head tracking, would notably aid in personal navigation and mobility, and would also be significantly more psychologically appealing from the standpoint of personal appearances. The capability for accommodation with no moving parts or feedback control is incorporated by employing camera designs that exhibit nearly infinite depth of field. Such an ultracompact optical imaging system requires a unique combination of refractive and diffractive optical elements and relaxed system constraints derived from human psychophysics. This configuration necessitates an extremely compact, short focal-length lens system with an f-number close to unity. Initially, these constraints appear highly aggressive from an optical design perspective. However, after careful analysis of the unique imaging requirements of a camera intended to work in conjunction with the relatively low pixellation levels of a retinal microstimulator array, it becomes clear that such a design is not only feasible, but could possibly be implemented with a single lens system.
Cost effective system for monitoring of fish migration with a camera
NASA Astrophysics Data System (ADS)
Sečnik, Matej; Brilly, Mitja; Vidmar, Andrej
2016-04-01
Within the European LIFE project Ljubljanica connects (LIFE10 NAT/SI/000142) we have developed a cost-effective solution for the monitoring of fish migration through the fish passes with the underwater camera. In the fish pass at Ambrožev trg and in the fish pass near the Fužine castle we installed a video camera called "Fishcam" to be able to monitor the migration of fish through the fish passes and success of its reconstruction. Live stream from fishcams installed in the fishpassesis available on our project website (http://ksh.fgg.uni-lj.si/ljubljanicaconnects/ang/12_camera). The system for the fish monitoring is made from two parts. First is the waterproof box for the computer with charger and the second part is the camera itself. We used a high sensitive Sony analogue camera. The advantage of this camera is that it has very good sensitivity in low light conditions, so it can take good quality pictures even at night with a minimum additional lighting. For the night recording we use additional IR reflector to illuminate passing fishes. The camera is connected to an 8-inch tablet PC. We decided to use a tablet PC because it is quite small, cheap, it is relatively fast and has a low power consumption. On the computer we use software which has advanced motion detection capabilities, so we can also detect the small fishes. When the fish is detected by a software, its photograph is automatically saved to local hard drive and for backup also on Google drive. The system for monitoring of fish migration has turned out to work very well. From the beginning of monitoring in June 2015 to end of the year there were more than 100.000 photographs produced. The first analysis of them was already prepared estimating fish species and their frequency in passing the fish pass.
Status of the photomultiplier-based FlashCam camera for the Cherenkov Telescope Array
NASA Astrophysics Data System (ADS)
Pühlhofer, G.; Bauer, C.; Eisenkolb, F.; Florin, D.; Föhr, C.; Gadola, A.; Garrecht, F.; Hermann, G.; Jung, I.; Kalekin, O.; Kalkuhl, C.; Kasperek, J.; Kihm, T.; Koziol, J.; Lahmann, R.; Manalaysay, A.; Marszalek, A.; Rajda, P. J.; Reimer, O.; Romaszkan, W.; Rupinski, M.; Schanz, T.; Schwab, T.; Steiner, S.; Straumann, U.; Tenzer, C.; Vollhardt, A.; Weitzel, Q.; Winiarski, K.; Zietara, K.
2014-07-01
The FlashCam project is preparing a camera prototype around a fully digital FADC-based readout system, for the medium sized telescopes (MST) of the Cherenkov Telescope Array (CTA). The FlashCam design is the first fully digital readout system for Cherenkov cameras, based on commercial FADCs and FPGAs as key components for digitization and triggering, and a high performance camera server as back end. It provides the option to easily implement different types of trigger algorithms as well as digitization and readout scenarios using identical hardware, by simply changing the firmware on the FPGAs. The readout of the front end modules into the camera server is Ethernet-based using standard Ethernet switches and a custom, raw Ethernet protocol. In the current implementation of the system, data transfer and back end processing rates of 3.8 GB/s and 2.4 GB/s have been achieved, respectively. Together with the dead-time-free front end event buffering on the FPGAs, this permits the cameras to operate at trigger rates of up to several ten kHz. In the horizontal architecture of FlashCam, the photon detector plane (PDP), consisting of photon detectors, preamplifiers, high voltage-, control-, and monitoring systems, is a self-contained unit, mechanically detached from the front end modules. It interfaces to the digital readout system via analogue signal transmission. The horizontal integration of FlashCam is expected not only to be more cost efficient, it also allows PDPs with different types of photon detectors to be adapted to the FlashCam readout system. By now, a 144-pixel mini-camera" setup, fully equipped with photomultipliers, PDP electronics, and digitization/ trigger electronics, has been realized and extensively tested. Preparations for a full-scale, 1764 pixel camera mechanics and a cooling system are ongoing. The paper describes the status of the project.
2D virtual texture on 3D real object with coded structured light
NASA Astrophysics Data System (ADS)
Molinier, Thierry; Fofi, David; Salvi, Joaquim; Gorria, Patrick
2008-02-01
Augmented reality is used to improve color segmentation on human body or on precious no touch artifacts. We propose a technique to project a synthesized texture on real object without contact. Our technique can be used in medical or archaeological application. By projecting a suitable set of light patterns onto the surface of a 3D real object and by capturing images with a camera, a large number of correspondences can be found and the 3D points can be reconstructed. We aim to determine these points of correspondence between cameras and projector from a scene without explicit points and normals. We then project an adjusted texture onto the real object surface. We propose a global and automatic method to virtually texture a 3D real object.
IRAIT project: future mid-IR operations at Dome C during summer
NASA Astrophysics Data System (ADS)
Tosti, Gino; IRAIT Collaboration
The project IRAIT consists of a robotic mid-infrared telescope that will be hosted at Dome C in the Italian-French Concordia station on the Antarctic Plateau. The telescope was built in collaboration with the PNRA (sectors Technology and Earth-Sun Interaction and Astrophysics). Its focal plane instrumentation is a mid-infrared Camera (5-25 mu m), based on the TIRCAM II prototype, which is the result of a join effort between Institutes of CNR and INAF. International collaborations with French and Spanish Institutes for the construction of a near infrared spectrographic camera have also been started. We present the status of the project and the ongoing developments that will make possible to start infrared observations at Dome C during the summer Antarctic campaign 2005-2006.
Fotogrammetria dell'Obelisco Vaticano con il Sole
NASA Astrophysics Data System (ADS)
Sigismondi, Costantino
2016-05-01
The Vatican Obelisk has been moved to St Peter's square by Domenico Fontana in 1586. The measurement of its height using the shadow on the floor is compared with Fontana's original data and with digital photo, corrected by perspective. A pincushion deformation is found in the camera.
Housing as a Determinant of Tongan Children’s Health: Innovative Methodology Using Wearable Cameras
Robinson, Andrew; Puloka, Viliami; Smith, Moira; Stanley, James; Signal, Louise
2017-01-01
Housing is a significant determinant of health, particularly in developing countries such as Tonga. Currently, very little is known about the quality of the housing in Tonga, as is the case with many developing countries, nor about the interaction between children and the home environment. This study aimed to identify the nature and extent of health risk factors and behaviours in Tongan houses from a child’s perspective. An innovative methodology was used, Kids’Cam Tonga. Seventy-two Class 6 children (10 to 13-year-olds) were randomly selected from 12 randomly selected schools in Tongatapu, the main island. Each participating child wore a wearable camera on lanyards around their neck. The device automatically took wide-angled, 136° images of the child’s perspective every seven seconds. The children were instructed to wear the camera all day from Friday morning to Sunday evening, inclusive. The analysis showed that the majority of Tongan children in the study live in houses that have structural deficiencies and hazards, including water damage (42%), mould (36%), and electrical (89%) and burn risk factors (28%). The findings suggest that improvements to the housing stock may reduce the associated health burden and increase buildings’ resilience to natural hazards. A collaborative approach between communities, community leaders, government and non-governmental organisations (NGOs) is urgently needed. This research methodology may be of value to other developing countries. PMID:28976919
Characterization of flotation color by machine vision
NASA Astrophysics Data System (ADS)
Siren, Ari
1999-09-01
Flotation is the most common industrial method by which valuable minerals are separated from waste rock after crushing and grinding the ore. For process control, flotation plants and devices are equipped with conventional and specialized sensors. However, certain variables are left to the visual observation of the operator, such as the color of the froth and the size of the bubbles in the froth. The ChaCo-Project (EU-Project 24931) was launched in November 1997. In this project a measuring station was built at the Pyhasalmi flotation plant. The system includes an RGB camera and a spectral color measuring instrument for the color inspection of the flotation. The RGB camera or visible spectral range is also measured to compare the operators' comments on the color of the froth relating to the sphalerite concentration and the process balance. Different dried mineral (sphalerite) ratios were studied with iron pyrite to find out about the minerals' typical spectral features. The correlation between sphalerite spectral reflectance and sphalerite concentration over various wavelengths are used to select the proper camera system with filters or to compare the results with the color information from the RGB camera. Various machine vision candidate techniques are discussed for this application and the preprocessed information of the dried mineral colors is used and adapted to the online measuring station. Moving froth bubbles produce total reflections, disturbing the color information. Polarization filters are used and the results are reported. Also the reflectance outside the visible light is studied and reported.
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.
Sky camera geometric calibration using solar observations
Urquhart, Bryan; Kurtz, Ben; Kleissl, Jan
2016-09-05
A camera model and associated automated calibration procedure for stationary daytime sky imaging cameras is presented. The specific modeling and calibration needs are motivated by remotely deployed cameras used to forecast solar power production where cameras point skyward and use 180° fisheye lenses. Sun position in the sky and on the image plane provides a simple and automated approach to calibration; special equipment or calibration patterns are not required. Sun position in the sky is modeled using a solar position algorithm (requiring latitude, longitude, altitude and time as inputs). Sun position on the image plane is detected using a simple image processing algorithm. Themore » performance evaluation focuses on the calibration of a camera employing a fisheye lens with an equisolid angle projection, but the camera model is general enough to treat most fixed focal length, central, dioptric camera systems with a photo objective lens. Calibration errors scale with the noise level of the sun position measurement in the image plane, but the calibration is robust across a large range of noise in the sun position. In conclusion, calibration performance on clear days ranged from 0.94 to 1.24 pixels root mean square error.« less
Autocalibration of a projector-camera system.
Okatani, Takayuki; Deguchi, Koichiro
2005-12-01
This paper presents a method for calibrating a projector-camera system that consists of multiple projectors (or multiple poses of a single projector), a camera, and a planar screen. We consider the problem of estimating the homography between the screen and the image plane of the camera or the screen-camera homography, in the case where there is no prior knowledge regarding the screen surface that enables the direct computation of the homography. It is assumed that the pose of each projector is unknown while its internal geometry is known. Subsequently, it is shown that the screen-camera homography can be determined from only the images projected by the projectors and then obtained by the camera, up to a transformation with four degrees of freedom. This transformation corresponds to arbitrariness in choosing a two-dimensional coordinate system on the screen surface and when this coordinate system is chosen in some manner, the screen-camera homography as well as the unknown poses of the projectors can be uniquely determined. A noniterative algorithm is presented, which computes the homography from three or more images. Several experimental results on synthetic as well as real images are shown to demonstrate the effectiveness of the method.
NASA Astrophysics Data System (ADS)
Mi, Yuhe; Huang, Yifan; Li, Lin
2015-08-01
Based on the location technique of beacon photogrammetry, Dual Camera Photogrammetry (DCP) algorithm was used to assist helicopters landing on the ship. In this paper, ZEMAX was used to simulate the two Charge Coupled Device (CCD) cameras imaging four beacons on both sides of the helicopter and output the image to MATLAB. Target coordinate systems, image pixel coordinate systems, world coordinate systems and camera coordinate systems were established respectively. According to the ideal pin-hole imaging model, the rotation matrix and translation vector of the target coordinate systems and the camera coordinate systems could be obtained by using MATLAB to process the image information and calculate the linear equations. On the basis mentioned above, ambient temperature and the positions of the beacons and cameras were changed in ZEMAX to test the accuracy of the DCP algorithm in complex sea status. The numerical simulation shows that in complex sea status, the position measurement accuracy can meet the requirements of the project.
NGEE Arctic Webcam Photographs, Barrow Environmental Observatory, Barrow, Alaska
Bob Busey; Larry Hinzman
2012-04-01
The NGEE Arctic Webcam (PTZ Camera) captures two views of seasonal transitions from its generally south-facing position on a tower located at the Barrow Environmental Observatory near Barrow, Alaska. Images are captured every 30 minutes. Historical images are available for download. The camera is operated by the U.S. DOE sponsored Next Generation Ecosystem Experiments - Arctic (NGEE Arctic) project.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Conder, A.; Mummolo, F. J.
The goal of the project was to develop a compact, large active area, high spatial resolution, high dynamic range, charge-coupled device (CCD) camera to replace film for digital imaging of visible light, ultraviolet radiation, and soft to penetrating X-rays. The camera head and controller needed to be capable of operation within a vacuum environment and small enough to be fielded within the small vacuum target chambers at LLNL.
VizieR Online Data Catalog: >20yrs of HST obs. of Cepheids in SNIa host gal. (Hoffmann+, 2016)
NASA Astrophysics Data System (ADS)
Hoffmann, S. L.; Macri, L. M.; Riess, A. G.; Yuan, W.; Casertano, S.; Foley, R. J.; Filippenko, A. V.; Tucker, B. E.; Chornock, R.; Silverman, J. M.; Welch, D. L.; Goobar, A.; Amanullah, R.
2017-01-01
HST observations of Cepheid variables (both archival or newly obtained) span more than two decades (1994-2016; see table 1). The earliest Cepheid observations we analyzed were obtained with the Wide Field and Planetary Camera 2 (WFPC2) as part of the initial efforts to measure H0 with HST (Freedman+ 2001ApJ...553...47F; Sandage+ 2006ApJ...653..843S) and were later used by Freedman+ (2012ApJ...758...24F) to reach beyond the LMC for the Carnegie Hubble Project. We also re-analyzed observations obtained in previous phases of our project (Riess+ 2009, J/ApJS/183/109; 2011, J/ApJ/730/119) with the Advanced Camera for Surveys (ACS) Wide Field Channel (WFC) and/or the Wide Field Camera 3 (WFC3) Ultraviolet and Visible Channel (UVIS). Finally, we obtained new observations of nine SN Ia hosts using WFC3. We obtained the majority of our optical images with these modern cameras, 113 and 132 unique epochs with ACS and WFC3, respectively, while WFPC2 contributes a smaller fraction with 67 epochs. (6 data files).
Imaging characteristics of photogrammetric camera systems
Welch, R.; Halliday, J.
1973-01-01
In view of the current interest in high-altitude and space photographic systems for photogrammetric mapping, the United States Geological Survey (U.S.G.S.) undertook a comprehensive research project designed to explore the practical aspects of applying the latest image quality evaluation techniques to the analysis of such systems. The project had two direct objectives: (1) to evaluate the imaging characteristics of current U.S.G.S. photogrammetric camera systems; and (2) to develop methodologies for predicting the imaging capabilities of photogrammetric camera systems, comparing conventional systems with new or different types of systems, and analyzing the image quality of photographs. Image quality was judged in terms of a number of evaluation factors including response functions, resolving power, and the detectability and measurability of small detail. The limiting capabilities of the U.S.G.S. 6-inch and 12-inch focal length camera systems were established by analyzing laboratory and aerial photographs in terms of these evaluation factors. In the process, the contributing effects of relevant parameters such as lens aberrations, lens aperture, shutter function, image motion, film type, and target contrast procedures for analyzing image quality and predicting and comparing performance capabilities. ?? 1973.
Optical correlator method and apparatus for particle image velocimetry processing
NASA Technical Reports Server (NTRS)
Farrell, Patrick V. (Inventor)
1991-01-01
Young's fringes are produced from a double exposure image of particles in a flowing fluid by passing laser light through the film and projecting the light onto a screen. A video camera receives the image from the screen and controls a spatial light modulator. The spatial modulator has a two dimensional array of cells the transmissiveness of which are controlled in relation to the brightness of the corresponding pixel of the video camera image of the screen. A collimated beam of laser light is passed through the spatial light modulator to produce a diffraction pattern which is focused onto another video camera, with the output of the camera being digitized and provided to a microcomputer. The diffraction pattern formed when the laser light is passed through the spatial light modulator and is focused to a point corresponds to the two dimensional Fourier transform of the Young's fringe pattern projected onto the screen. The data obtained fro This invention was made with U.S. Government support awarded by the Department of the Army (DOD) and NASA grand number(s): DOD #DAAL03-86-K0174 and NASA #NAG3-718. The U.S. Government has certain rights in this invention.
High-performance camera module for fast quality inspection in industrial printing applications
NASA Astrophysics Data System (ADS)
Fürtler, Johannes; Bodenstorfer, Ernst; Mayer, Konrad J.; Brodersen, Jörg; Heiss, Dorothea; Penz, Harald; Eckel, Christian; Gravogl, Klaus; Nachtnebel, Herbert
2007-02-01
Today, printing products which must meet highest quality standards, e.g., banknotes, stamps, or vouchers, are automatically checked by optical inspection systems. Typically, the examination of fine details of the print or security features demands images taken from various perspectives, with different spectral sensitivity (visible, infrared, ultraviolet), and with high resolution. Consequently, the inspection system is equipped with several cameras and has to cope with an enormous data rate to be processed in real-time. Hence, it is desirable to move image processing tasks into the camera to reduce the amount of data which has to be transferred to the (central) image processing system. The idea is to transfer relevant information only, i.e., features of the image instead of the raw image data from the sensor. These features are then further processed. In this paper a color line-scan camera for line rates up to 100 kHz is presented. The camera is based on a commercial CMOS (complementary metal oxide semiconductor) area image sensor and a field programmable gate array (FPGA). It implements extraction of image features which are well suited to detect print flaws like blotches of ink, color smears, splashes, spots and scratches. The camera design and several image processing methods implemented on the FPGA are described, including flat field correction, compensation of geometric distortions, color transformation, as well as decimation and neighborhood operations.
Generalized parallel-perspective stereo mosaics from airborne video.
Zhu, Zhigang; Hanson, Allen R; Riseman, Edward M
2004-02-01
In this paper, we present a new method for automatically and efficiently generating stereoscopic mosaics by seamless registration of images collected by a video camera mounted on an airborne platform. Using a parallel-perspective representation, a pair of geometrically registered stereo mosaics can be precisely constructed under quite general motion. A novel parallel ray interpolation for stereo mosaicing (PRISM) approach is proposed to make stereo mosaics seamless in the presence of obvious motion parallax and for rather arbitrary scenes. Parallel-perspective stereo mosaics generated with the PRISM method have better depth resolution than perspective stereo due to the adaptive baseline geometry. Moreover, unlike previous results showing that parallel-perspective stereo has a constant depth error, we conclude that the depth estimation error of stereo mosaics is in fact a linear function of the absolute depths of a scene. Experimental results on long video sequences are given.
Camera Image Transformation and Registration for Safe Spacecraft Landing and Hazard Avoidance
NASA Technical Reports Server (NTRS)
Jones, Brandon M.
2005-01-01
Inherent geographical hazards of Martian terrain may impede a safe landing for science exploration spacecraft. Surface visualization software for hazard detection and avoidance may accordingly be applied in vehicles such as the Mars Exploration Rover (MER) to induce an autonomous and intelligent descent upon entering the planetary atmosphere. The focus of this project is to develop an image transformation algorithm for coordinate system matching between consecutive frames of terrain imagery taken throughout descent. The methodology involves integrating computer vision and graphics techniques, including affine transformation and projective geometry of an object, with the intrinsic parameters governing spacecraft dynamic motion and camera calibration.
The Many Dimensions of Program Management
NASA Technical Reports Server (NTRS)
Dean, Edwin B.
1992-01-01
For the purposes of this paper, program refers to a collection of activities or projects which must be performed according to a plan or schedule. The Space Exploration Initiative within the National Aeronautics and Space Administration (NASA) is an example. Dimensionality refers to both the various perspectives of a program and to the components within that perspective. It is, thus, appropriate to think of dimensions of dimensionality. For example, one dimension or perspective of a program is the projects which perform the program. Within the project dimension, the individual projects are the components of that dimensionality. The number of projects defines the spatial dimensionality of the project dimension. Thus, each perspective or dimension has a dimensionality of its own. The structure and associated values of all the various perspectives of a program define the program. A project refers to the collection of activities required to conceive, sell, design, develop, evaluate, produce, operate, support, evolve, and retire a given system. A project thus effects the life cycle of given system. A project is, thus, the system to conceive, sell, design, develop, evaluate, produce, operate, support, evolve, and retire a system. A program, thus, effects the life cycle of the collection of projects required to effect the collection of systems required to implement the program.
After Conquering 'Husband Hill,' Spirit Moves On (Stereo)
NASA Technical Reports Server (NTRS)
2005-01-01
[figure removed for brevity, see original site] Left-eye view of a stereo pair for PIA03062 [figure removed for brevity, see original site] Right-eye view of a stereo pair for PIA03062 The first explorer ever to scale a summit on another planet, NASA's Mars Exploration Rover Spirit has begun a long trek downward from the top of 'Husband Hill' to new destinations. As shown in this 180-degree panorama from east of the summit, Spirit's earlier tracks are no longer visible. They are off to the west (to the left in this view). Spirit's next destination is 'Haskin Ridge,' straight ahead along the edge of the steep cliff on the right side of this panorama. The scene is a mosaic of images that Spirit took with the navigation camera on the rover's 635th Martian day, or sol, (Oct. 16, 2005) of exploration of Gusev Crater on Mars. This stereo view is presented in a cylindrical-perspective projection with geometric seam correction.Brain-computer interface using P300 and virtual reality: a gaming approach for treating ADHD.
Rohani, Darius Adam; Sorensen, Helge B D; Puthusserypady, Sadasivan
2014-01-01
This paper presents a novel brain-computer interface (BCI) system aiming at the rehabilitation of attention-deficit/hyperactive disorder in children. It uses the P300 potential in a series of feedback games to improve the subjects' attention. We applied a support vector machine (SVM) using temporal and template-based features to detect these P300 responses. In an experimental setup using five subjects, an average error below 30% was achieved. To make it more challenging the BCI system has been embedded inside an immersive 3D virtual reality (VR) classroom with simulated distractions, which was created by combining a low-cost infrared camera and an "off-axis perspective projection" algorithm. This system is intended for kids by operating with four electrodes, as well as a non-intrusive VR setting. With the promising results, and considering the simplicity of the scheme, we hope to encourage future studies to adapt the techniques presented in this study.
Opportunity's Surroundings on Sol 1687 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11739 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11739 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, 360-degree view of the rover's surroundings on the 1,687th Martian day, or sol, of its surface mission (Oct. 22, 2008). The view appears three-dimensional when viewed through red-blue glasses. Opportunity had driven 133 meters (436 feet) that sol, crossing sand ripples up to about 10 centimeters (4 inches) tall. The tracks visible in the foreground are in the east-northeast direction. Opportunity's position on Sol 1687 was about 300 meters southwest of Victoria Crater. The rover was beginning a long trek toward a much larger crater, Endeavour, about 12 kilometers (7 miles) to the southeast. This panorama combines right-eye and left-eye views presented as cylindrical-perspective projections with geometric seam correction.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.
OpenCV and TYZX : video surveillance for tracking.
DOE Office of Scientific and Technical Information (OSTI.GOV)
He, Jim; Spencer, Andrew; Chu, Eric
2008-08-01
As part of the National Security Engineering Institute (NSEI) project, several sensors were developed in conjunction with an assessment algorithm. A camera system was developed in-house to track the locations of personnel within a secure room. In addition, a commercial, off-the-shelf (COTS) tracking system developed by TYZX was examined. TYZX is a Bay Area start-up that has developed its own tracking hardware and software which we use as COTS support for robust tracking. This report discusses the pros and cons of each camera system, how they work, a proposed data fusion method, and some visual results. Distributed, embedded image processingmore » solutions show the most promise in their ability to track multiple targets in complex environments and in real-time. Future work on the camera system may include three-dimensional volumetric tracking by using multiple simple cameras, Kalman or particle filtering, automated camera calibration and registration, and gesture or path recognition.« less
NASA Astrophysics Data System (ADS)
Balthasar, Heike; Dumke, Alexander; van Gasselt, Stephan; Gross, Christoph; Michael, Gregory; Musiol, Stefanie; Neu, Dominik; Platz, Thomas; Rosenberg, Heike; Schreiner, Björn; Walter, Sebastian
2014-05-01
Since 2003 the High Resolution Stereo Camera (HRSC) experiment on the Mars Express mission is in orbit around Mars. First images were sent to Earth on January 14th, 2004. The goal-oriented HRSC data dissemination and the transparent representation of the associated work and results are the main aspects that contributed to the success in the public perception of the experiment. The Planetary Sciences and Remote Sensing Group at Freie Universität Berlin (FUB) offers both, an interactive web based data access, and browse/download options for HRSC press products [www.fu-berlin.de/planets]. Close collaborations with exhibitors as well as print and digital media representatives allows for regular and directed dissemination of, e.g., conventional imagery, orbital/synthetic surface epipolar images, video footage, and high-resolution displays. On a monthly basis we prepare press releases in close collaboration with the European Space Agency (ESA) and the German Aerospace Center (DLR) [http://www.geo.fu-berlin.de/en/geol/fachrichtungen/planet/press/index.html]. A release comprises panchromatic, colour, anaglyph, and perspective views of a scene taken from an HRSC image of the Martian surface. In addition, a context map and descriptive texts in English and German are provided. More sophisticated press releases include elaborate animations and simulated flights over the Martian surface, perspective views of stereo data combined with colour and high resolution, mosaics, and perspective views of data mosaics. Altogether 970 high quality PR products and 15 movies were created at FUB during the last decade and published via FUB/DLR/ESA platforms. We support educational outreach events, as well as permanent and special exhibitions. Examples for that are the yearly "Science Fair", where special programs for kids are offered, and the exhibition "Mars Mission and Vision" which is on tour until 2015 through 20 German towns, showing 3-D movies, surface models, and images of the HRSC camera experiment. Press and media appearances of group members, and talks to school classes and interested communities also contribute to the public outreach. For HRSC data dissemination we use digital platforms. Since 2007 HRSC image data can be viewed and accessed via the online interface HRSCview [http://hrscview.fu-berlin.de] which was built in cooperation with the DLR Institute for Planetary Research. Additionally HRSC ortho images (level 4) are presented in a modern MapServer setup in GIS-read format since 2013 [http://www.geo.fu-berlin.de/en/geol/fachrichtungen/planet/projects/marsexpress/level4downloads/index.html]. All of these offers ensured the accessibility of HRSC data and products to the science community as well as to the general public for the last ten years and will do so also in the future, taking advantage of modern and user-optimized applications and networks.
Frames of Reference in the Classroom
ERIC Educational Resources Information Center
Grossman, Joshua
2012-01-01
The classic film "Frames of Reference" effectively illustrates concepts involved with inertial and non-inertial reference frames. In it, Donald G. Ivey and Patterson Hume use the cameras perspective to allow the viewer to see motion in reference frames translating with a constant velocity, translating while accelerating, and rotating--all with…
How an Exchange of Perspectives Led to Tentative Ethical Guidelines for Visual Ethnography
ERIC Educational Resources Information Center
Pope, Clive C.; De Luca, Rosemary; Tolich, Martin
2010-01-01
Qualitative research, especially visual ethnography, is an iterative not a linear process, replete with good intentions, false starts, mistaken assumptions, miscommunication and a continually revised statement of the problem. That the camera freezes everything and everyone in the frame only complicates ethical considerations. This work, jointly…
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.
An ordinary camera in an extraordinary location: Outreach with the Mars Webcam
NASA Astrophysics Data System (ADS)
Ormston, T.; Denis, M.; Scuka, D.; Griebel, H.
2011-09-01
The European Space Agency's Mars Express mission was launched in 2003 and was Europe's first mission to Mars. On-board was a small camera designed to provide ‘visual telemetry’ of the separation of the Beagle-2 lander. After achieving its goal it was shut down while the primary science mission of Mars Express got underway. In 2007 this camera was reactivated by the flight control team of Mars Express for the purpose of providing public education and outreach—turning it into the ‘Mars Webcam’.The camera is a small, 640×480 pixel colour CMOS camera with a wide-angle 30°×40° field of view. This makes it very similar in almost every way to the average home PC webcam. The major difference is that this webcam is not in an average location but is instead in orbit around Mars. On a strict basis of non-interference with the primary science activities, the camera is turned on to provide unique wide-angle views of the planet below.A highly automated process ensures that the observations are scheduled on the spacecraft and then uploaded to the internet as rapidly as possible. There is no intermediate stage, so that visitors to the Mars Webcam blog serve as ‘citizen scientists’. Full raw datasets and processing instructions are provided along with a mechanism to allow visitors to comment on the blog. Members of the public are encouraged to use this in either a personal or an educational context and work with the images. We then take their excellent work and showcase it back on the blog. We even apply techniques developed by them to improve the data and webcam experience for others.The accessibility and simplicity of the images also makes the data ideal for educational use, especially as educational projects can then be showcased on the site as inspiration for others. The oft-neglected target audience of space enthusiasts is also important as this allows them to participate as part of an interplanetary instrument team.This paper will cover the history of the project and the technical background behind using the camera and linking the results to an accessible blog format. It will also cover the outreach successes of the project, some of the contributions from the Mars Webcam community, opportunities to use and work with the Mars Webcam and plans for future uses of the camera.
NASA Astrophysics Data System (ADS)
Yoon, Soweon; Jung, Ho Gi; Park, Kang Ryoung; Kim, Jaihie
2009-03-01
Although iris recognition is one of the most accurate biometric technologies, it has not yet been widely used in practical applications. This is mainly due to user inconvenience during the image acquisition phase. Specifically, users try to adjust their eye position within small capture volume at a close distance from the system. To overcome these problems, we propose a novel iris image acquisition system that provides users with unconstrained environments: a large operating range, enabling movement from standing posture, and capturing good-quality iris images in an acceptable time. The proposed system has the following three contributions compared with previous works: (1) the capture volume is significantly increased by using a pan-tilt-zoom (PTZ) camera guided by a light stripe projection, (2) the iris location in the large capture volume is found fast due to 1-D vertical face searching from the user's horizontal position obtained by the light stripe projection, and (3) zooming and focusing on the user's irises at a distance are accurate and fast using the estimated 3-D position of a face by the light stripe projection and the PTZ camera. Experimental results show that the proposed system can capture good-quality iris images in 2.479 s on average at a distance of 1.5 to 3 m, while allowing a limited amount of movement by the user.
Calcium neuroimaging in behaving zebrafish larvae using a turn-key light field camera
NASA Astrophysics Data System (ADS)
Cruz Perez, Carlos; Lauri, Antonella; Symvoulidis, Panagiotis; Cappetta, Michele; Erdmann, Arne; Westmeyer, Gil Gregor
2015-09-01
Reconstructing a three-dimensional scene from multiple simultaneously acquired perspectives (the light field) is an elegant scanless imaging concept that can exceed the temporal resolution of currently available scanning-based imaging methods for capturing fast cellular processes. We tested the performance of commercially available light field cameras on a fluorescent microscopy setup for monitoring calcium activity in the brain of awake and behaving reporter zebrafish larvae. The plenoptic imaging system could volumetrically resolve diverse neuronal response profiles throughout the zebrafish brain upon stimulation with an aversive odorant. Behavioral responses of the reporter fish could be captured simultaneously together with depth-resolved neuronal activity. Overall, our assessment showed that with some optimizations for fluorescence microscopy applications, commercial light field cameras have the potential of becoming an attractive alternative to custom-built systems to accelerate molecular imaging research on cellular dynamics.
Calcium neuroimaging in behaving zebrafish larvae using a turn-key light field camera.
Perez, Carlos Cruz; Lauri, Antonella; Symvoulidis, Panagiotis; Cappetta, Michele; Erdmann, Arne; Westmeyer, Gil Gregor
2015-09-01
Reconstructing a three-dimensional scene from multiple simultaneously acquired perspectives (the light field) is an elegant scanless imaging concept that can exceed the temporal resolution of currently available scanning-based imaging methods for capturing fast cellular processes. We tested the performance of commercially available light field cameras on a fluorescent microscopy setup for monitoring calcium activity in the brain of awake and behaving reporter zebrafish larvae. The plenoptic imaging system could volumetrically resolve diverse neuronal response profiles throughout the zebrafish brain upon stimulation with an aversive odorant. Behavioral responses of the reporter fish could be captured simultaneously together with depth-resolved neuronal activity. Overall, our assessment showed that with some optimizations for fluorescence microscopy applications, commercial light field cameras have the potential of becoming an attractive alternative to custom-built systems to accelerate molecular imaging research on cellular dynamics.
Lee, Chang Kyu; Kim, Youngjun; Lee, Nam; Kim, Byeongwoo; Kim, Doyoung; Yi, Seong
2017-02-15
Study for feasibility of commercially available action cameras in recording video of spine. Recent innovation of the wearable action camera with high-definition video recording enables surgeons to use camera in the operation at ease without high costs. The purpose of this study is to compare the feasibility, safety, and efficacy of commercially available action cameras in recording video of spine surgery. There are early reports of medical professionals using Google Glass throughout the hospital, Panasonic HX-A100 action camera, and GoPro. This study is the first report for spine surgery. Three commercially available cameras were tested: GoPro Hero 4 Silver, Google Glass, and Panasonic HX-A100 action camera. Typical spine surgery was selected for video recording; posterior lumbar laminectomy and fusion. Three cameras were used by one surgeon and video was recorded throughout the operation. The comparison was made on the perspective of human factor, specification, and video quality. The most convenient and lightweight device for wearing and holding throughout the long operation time was Google Glass. The image quality; all devices except Google Glass supported HD format and GoPro has unique 2.7K or 4K resolution. Quality of video resolution was best in GoPro. Field of view, GoPro can adjust point of interest, field of view according to the surgery. Narrow FOV option was the best for recording in GoPro to share the video clip. Google Glass has potentials by using application programs. Connectivity such as Wi-Fi and Bluetooth enables video streaming for audience, but only Google Glass has two-way communication feature in device. Action cameras have the potential to improve patient safety, operator comfort, and procedure efficiency in the field of spinal surgery and broadcasting a surgery with development of the device and applied program in the future. N/A.
The Large Synoptic Survey Telescope (LSST) Camera
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
Ranked as the top ground-based national priority for the field for the current decade, LSST is currently under construction in Chile. The U.S. Department of Energy’s SLAC National Accelerator Laboratory is leading the construction of the LSST camera – the largest digital camera ever built for astronomy. SLAC Professor Steven M. Kahn is the overall Director of the LSST project, and SLAC personnel are also participating in the data management. The National Science Foundation is the lead agency for construction of the LSST. Additional financial support comes from the Department of Energy and private funding raised by the LSST Corporation.
Optical stereo video signal processor
NASA Technical Reports Server (NTRS)
Craig, G. D. (Inventor)
1985-01-01
An otpical video signal processor is described which produces a two-dimensional cross-correlation in real time of images received by a stereo camera system. The optical image of each camera is projected on respective liquid crystal light valves. The images on the liquid crystal valves modulate light produced by an extended light source. This modulated light output becomes the two-dimensional cross-correlation when focused onto a video detector and is a function of the range of a target with respect to the stereo camera. Alternate embodiments utilize the two-dimensional cross-correlation to determine target movement and target identification.
Toolkit for testing scientific CCD cameras
NASA Astrophysics Data System (ADS)
Uzycki, Janusz; Mankiewicz, Lech; Molak, Marcin; Wrochna, Grzegorz
2006-03-01
The CCD Toolkit (1) is a software tool for testing CCD cameras which allows to measure important characteristics of a camera like readout noise, total gain, dark current, 'hot' pixels, useful area, etc. The application makes a statistical analysis of images saved in files with FITS format, commonly used in astronomy. A graphical interface is based on the ROOT package, which offers high functionality and flexibility. The program was developed in a way to ensure future compatibility with different operating systems: Windows and Linux. The CCD Toolkit was created for the "Pie of the Sky" project collaboration (2).
NASA Astrophysics Data System (ADS)
Sao Sabbas, F. T.
2012-12-01
This project has the goal of establishing the Collaborative Network LEONA, to study the electrodynamical coupling of the atmospheric layers signaled by Transient Luminous Events - TLEs and high energy emissions from thunderstorms. We will develop and install a remotely controlled network of cameras to perform TLE observations in different locations in South America and one neutron detector in southern Brazil. The camera network will allow building a continuous data set of the phenomena studied in this continent. The first two trial units of the camera network are already installed, in Brazil and Peru, and two more will be installed until December 2012, in Argentina and Brazil. We expect to determine the TLE geographic distribution, occurrence rate, morphology, and possible coupling with other geophysical phenomena in South America, such as the South Atlantic Magnetic Anomaly - SAMA. We also expect to study thunderstorm neutron emissions in a region of intense electrical activity, measuring neutron fluxes with high time resolution simultaneously with TLEs and lightning for the first time in South America. Using an intensified high-speed camera for TLE observation during 2 campaigns we expect to be able to determine the duration and spatial- temporal development of the TLEs observed, to study the structure and initiation of sprites and to measure the velocity of development of sprite structures and the sprite delay. The camera was acquired via the FAPESP project DEELUMINOS (2005-2010), which also nucleated our research group Atmospheric Electrodynamical Coupling - ACATMOS. LEONA will nucleate this research in other institutions in Brazil and other countries in South America, providing continuity for this important research in our region. The camera network will be an unique tool to perform consistent long term TLE observation, and in fact is the only way to accumulate a data set for a climatological study of South America, since satellite instrumentation turns off in this region to avoid damages due to the South Atlantic Magnetic Anomaly - SAMA. Thus this project is not only a potential benchmark in TLE research by creating a collaborative network in Latin America and nucleating this research locally, it is also strategic since LEONA's camera network will be able to provide extremely valuable information to fill up this gap that most satellite measurements have.
2016-10-18
perspective view of Charon's informally named "Serenity Chasm" consists of topography generated from stereo reconstruction of images taken by New Horizons' Long Range Reconnaissance Imager (LORRI) and Multispectral Visible Imaging Camera (MVIC), supplemented by a "shape-from-shading" algorithm. The topography is then overlain with the PIA21128 image mosaic and the perspective view is rendered. The MVIC image was taken from a distance of 45,458 miles (73,159 kilometers) while the LORRI picture was taken from 19,511 miles (31,401 kilometers) away, both on July 14, 2015. http://photojournal.jpl.nasa.gov/catalog/PIA21129
Development of high-speed video cameras
NASA Astrophysics Data System (ADS)
Etoh, Takeharu G.; Takehara, Kohsei; Okinaka, Tomoo; Takano, Yasuhide; Ruckelshausen, Arno; Poggemann, Dirk
2001-04-01
Presented in this paper is an outline of the R and D activities on high-speed video cameras, which have been done in Kinki University since more than ten years ago, and are currently proceeded as an international cooperative project with University of Applied Sciences Osnabruck and other organizations. Extensive marketing researches have been done, (1) on user's requirements on high-speed multi-framing and video cameras by questionnaires and hearings, and (2) on current availability of the cameras of this sort by search of journals and websites. Both of them support necessity of development of a high-speed video camera of more than 1 million fps. A video camera of 4,500 fps with parallel readout was developed in 1991. A video camera with triple sensors was developed in 1996. The sensor is the same one as developed for the previous camera. The frame rate is 50 million fps for triple-framing and 4,500 fps for triple-light-wave framing, including color image capturing. Idea on a video camera of 1 million fps with an ISIS, In-situ Storage Image Sensor, was proposed in 1993 at first, and has been continuously improved. A test sensor was developed in early 2000, and successfully captured images at 62,500 fps. Currently, design of a prototype ISIS is going on, and, hopefully, will be fabricated in near future. Epoch-making cameras in history of development of high-speed video cameras by other persons are also briefly reviewed.
Field Portable Digital Ophthalmoscope/Fundus Camera. Phase I
1997-05-01
robbing injuries and pathologies. Included are retinal detachments, laser damage, CMV retinitis , retinitis pigmentosa , glaucoma, tumors, and the like...RMI-S, Fort Detrick, Frederick, Maryland 21702-5012. 13. ABSTRACT (Maximum 200 Retinal imaging is key for diagnoses and treatment of various eye-sight...personnel, and generally only used by ophthalmologists or in hospital settings. The retinal camera of this project will revolutionize retinal imaging
DOTD support for UTC project : travel time estimation using bluetooth, [research project capsule].
DOT National Transportation Integrated Search
2013-10-01
Travel time estimates are useful tools for measuring congestion in an urban area. Current : practice involves using probe vehicles or video cameras to measure travel time, but this is a laborintensive and expensive means of obtaining the information....
NASA Technical Reports Server (NTRS)
Park, Jung- Ho; Kim, Jongmin; Zukic, Muamer; Torr, Douglas G.
1994-01-01
We report the design of multilayer reflective filters for the self-filtering cameras of the NUVIEWS project. Wide angle self-filtering cameras were designed to image the C IV (154.9 nm) line emission, and H2 Lyman band fluorescence (centered at 161 nm) over a 20 deg x 30 deg field of view. A key element of the filter design includes the development of pi-multilayers optimized to provide maximum reflectance at 154.9 nm and 161 nm for the respective cameras without significant spectral sensitivity to the large cone angle of the incident radiation. We applied self-filtering concepts to design NUVIEWS telescope filters that are composed of three reflective mirrors and one folding mirror. The filters with narrowband widths of 6 and 8 rim at 154.9 and 161 nm, respectively, have net throughputs of more than 50 % with average blocking of out-of-band wavelengths better than 3 x 10(exp -4)%.
Calibration of stereo rigs based on the backward projection process
NASA Astrophysics Data System (ADS)
Gu, Feifei; Zhao, Hong; Ma, Yueyang; Bu, Penghui; Zhao, Zixin
2016-08-01
High-accuracy 3D measurement based on binocular vision system is heavily dependent on the accurate calibration of two rigidly-fixed cameras. In most traditional calibration methods, stereo parameters are iteratively optimized through the forward imaging process (FIP). However, the results can only guarantee the minimal 2D pixel errors, but not the minimal 3D reconstruction errors. To address this problem, a simple method to calibrate a stereo rig based on the backward projection process (BPP) is proposed. The position of a spatial point can be determined separately from each camera by planar constraints provided by the planar pattern target. Then combined with pre-defined spatial points, intrinsic and extrinsic parameters of the stereo-rig can be optimized by minimizing the total 3D errors of both left and right cameras. An extensive performance study for the method in the presence of image noise and lens distortions is implemented. Experiments conducted on synthetic and real data demonstrate the accuracy and robustness of the proposed method.
An augmented-reality edge enhancement application for Google Glass.
Hwang, Alex D; Peli, Eli
2014-08-01
Google Glass provides a platform that can be easily extended to include a vision enhancement tool. We have implemented an augmented vision system on Glass, which overlays enhanced edge information over the wearer's real-world view, to provide contrast-improved central vision to the Glass wearers. The enhanced central vision can be naturally integrated with scanning. Google Glass' camera lens distortions were corrected by using an image warping. Because the camera and virtual display are horizontally separated by 16 mm, and the camera aiming and virtual display projection angle are off by 10°, the warped camera image had to go through a series of three-dimensional transformations to minimize parallax errors before the final projection to the Glass' see-through virtual display. All image processes were implemented to achieve near real-time performance. The impacts of the contrast enhancements were measured for three normal-vision subjects, with and without a diffuser film to simulate vision loss. For all three subjects, significantly improved contrast sensitivity was achieved when the subjects used the edge enhancements with a diffuser film. The performance boost is limited by the Glass camera's performance. The authors assume that this accounts for why performance improvements were observed only with the diffuser filter condition (simulating low vision). Improvements were measured with simulated visual impairments. With the benefit of see-through augmented reality edge enhancement, natural visual scanning process is possible and suggests that the device may provide better visual function in a cosmetically and ergonomically attractive format for patients with macular degeneration.
Servo-controlled intravital microscope system
NASA Technical Reports Server (NTRS)
Mansour, M. N.; Wayland, H. J.; Chapman, C. P. (Inventor)
1975-01-01
A microscope system is described for viewing an area of a living body tissue that is rapidly moving, by maintaining the same area in the field-of-view and in focus. A focus sensing portion of the system includes two video cameras at which the viewed image is projected, one camera being slightly in front of the image plane and the other slightly behind it. A focus sensing circuit for each camera differentiates certain high frequency components of the video signal and then detects them and passes them through a low pass filter, to provide dc focus signal whose magnitudes represent the degree of focus. An error signal equal to the difference between the focus signals, drives a servo that moves the microscope objective so that an in-focus view is delivered to an image viewing/recording camera.
Calibration and accuracy analysis of a focused plenoptic camera
NASA Astrophysics Data System (ADS)
Zeller, N.; Quint, F.; Stilla, U.
2014-08-01
In this article we introduce new methods for the calibration of depth images from focused plenoptic cameras and validate the results. We start with a brief description of the concept of a focused plenoptic camera and how from the recorded raw image a depth map can be estimated. For this camera, an analytical expression of the depth accuracy is derived for the first time. In the main part of the paper, methods to calibrate a focused plenoptic camera are developed and evaluated. The optical imaging process is calibrated by using a method which is already known from the calibration of traditional cameras. For the calibration of the depth map two new model based methods, which make use of the projection concept of the camera are developed. These new methods are compared to a common curve fitting approach, which is based on Taylor-series-approximation. Both model based methods show significant advantages compared to the curve fitting method. They need less reference points for calibration than the curve fitting method and moreover, supply a function which is valid in excess of the range of calibration. In addition the depth map accuracy of the plenoptic camera was experimentally investigated for different focal lengths of the main lens and is compared to the analytical evaluation.
IDEAS and App Development Internship in Hardware and Software Design
NASA Technical Reports Server (NTRS)
Alrayes, Rabab D.
2016-01-01
In this report, I will discuss the tasks and projects I have completed while working as an electrical engineering intern during the spring semester of 2016 at NASA Kennedy Space Center. In the field of software development, I completed tasks for the G-O Caching Mobile App and the Asbestos Management Information System (AMIS) Web App. The G-O Caching Mobile App was written in HTML, CSS, and JavaScript on the Cordova framework, while the AMIS Web App is written in HTML, CSS, JavaScript, and C# on the AngularJS framework. My goals and objectives on these two projects were to produce an app with an eye-catching and intuitive User Interface (UI), which will attract more employees to participate; to produce a fully-tested, fully functional app which supports workforce engagement and exploration; to produce a fully-tested, fully functional web app that assists technicians working in asbestos management. I also worked in hardware development on the Integrated Display and Environmental Awareness System (IDEAS) wearable technology project. My tasks on this project were focused in PCB design and camera integration. My goals and objectives for this project were to successfully integrate fully functioning custom hardware extenders on the wearable technology headset to minimize the size of hardware on the smart glasses headset for maximum user comfort; to successfully integrate fully functioning camera onto the headset. By the end of this semester, I was able to successfully develop four extender boards to minimize hardware on the headset, and assisted in integrating a fully-functioning camera into the system.
DOT National Transportation Integrated Search
1999-11-01
Connecticut Department of Transportation personnel used an infrared camera to observe thermal segregation of hot mix asphalt during pavement construction. Several sites were selected for study from ongoing paving projects. During paving operations, t...
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
NASA Astrophysics Data System (ADS)
Pani, R.; Pellegrini, R.; Betti, M.; De Vincentis, G.; Cinti, M. N.; Bennati, P.; Vittorini, F.; Casali, V.; Mattioli, M.; Orsolini Cencelli, V.; Navarria, F.; Bollini, D.; Moschini, G.; Iurlaro, G.; Montani, L.; de Notaristefani, F.
2007-02-01
The principal limiting factor in the clinical acceptance of scintimammography is certainly its low sensitivity for cancers sized <1 cm, mainly due to the lack of equipment specifically designed for breast imaging. The National Institute of Nuclear Physics (INFN) has been developing a new scintillation camera based on Lanthanum tri-Bromide Cerium-doped crystal (LaBr 3:Ce), that demonstrating superior imaging performances with respect to the dedicated scintillation γ-camera that was previously developed. The proposed detector consists of continuous LaBr 3:Ce scintillator crystal coupled to a Hamamatsu H8500 Flat Panel PMT. One centimeter thick crystal has been chosen to increase crystal detection efficiency. In this paper, we propose a comparison and evaluation between lanthanum γ-camera and a Multi PSPMT camera, NaI(Tl) discrete pixel based, previously developed under "IMI" Italian project for technological transfer of INFN. A phantom study has been developed to test both the cameras before introducing them in clinical trials. High resolution scans produced by LaBr 3:Ce camera showed higher tumor contrast with a detailed imaging of uptake area than pixellated NaI(Tl) dedicated camera. Furthermore, with the lanthanum camera, the Signal-to-Noise Ratio ( SNR) value was increased for a lesion as small as 5 mm, with a consequent strong improvement in detectability.
NASA Astrophysics Data System (ADS)
Peltoniemi, Mikko; Aurela, Mika; Böttcher, Kristin; Kolari, Pasi; Loehr, John; Karhu, Jouni; Linkosalmi, Maiju; Melih Tanis, Cemal; Tuovinen, Juha-Pekka; Nadir Arslan, Ali
2018-01-01
In recent years, monitoring of the status of ecosystems using low-cost web (IP) or time lapse cameras has received wide interest. With broad spatial coverage and high temporal resolution, networked cameras can provide information about snow cover and vegetation status, serve as ground truths to Earth observations and be useful for gap-filling of cloudy areas in Earth observation time series. Networked cameras can also play an important role in supplementing laborious phenological field surveys and citizen science projects, which also suffer from observer-dependent observation bias. We established a network of digital surveillance cameras for automated monitoring of phenological activity of vegetation and snow cover in the boreal ecosystems of Finland. Cameras were mounted at 14 sites, each site having 1-3 cameras. Here, we document the network, basic camera information and access to images in the permanent data repository (http://www.zenodo.org/communities/phenology_camera/). Individual DOI-referenced image time series consist of half-hourly images collected between 2014 and 2016 (https://doi.org/10.5281/zenodo.1066862). Additionally, we present an example of a colour index time series derived from images from two contrasting sites.
Pre-flight and On-orbit Geometric Calibration of the Lunar Reconnaissance Orbiter Camera
NASA Astrophysics Data System (ADS)
Speyerer, E. J.; Wagner, R. V.; Robinson, M. S.; Licht, A.; Thomas, P. C.; Becker, K.; Anderson, J.; Brylow, S. M.; Humm, D. C.; Tschimmel, M.
2016-04-01
The Lunar Reconnaissance Orbiter Camera (LROC) consists of two imaging systems that provide multispectral and high resolution imaging of the lunar surface. The Wide Angle Camera (WAC) is a seven color push-frame imager with a 90∘ field of view in monochrome mode and 60∘ field of view in color mode. From the nominal 50 km polar orbit, the WAC acquires images with a nadir ground sampling distance of 75 m for each of the five visible bands and 384 m for the two ultraviolet bands. The Narrow Angle Camera (NAC) consists of two identical cameras capable of acquiring images with a ground sampling distance of 0.5 m from an altitude of 50 km. The LROC team geometrically calibrated each camera before launch at Malin Space Science Systems in San Diego, California and the resulting measurements enabled the generation of a detailed camera model for all three cameras. The cameras were mounted and subsequently launched on the Lunar Reconnaissance Orbiter (LRO) on 18 June 2009. Using a subset of the over 793000 NAC and 207000 WAC images of illuminated terrain collected between 30 June 2009 and 15 December 2013, we improved the interior and exterior orientation parameters for each camera, including the addition of a wavelength dependent radial distortion model for the multispectral WAC. These geometric refinements, along with refined ephemeris, enable seamless projections of NAC image pairs with a geodetic accuracy better than 20 meters and sub-pixel precision and accuracy when orthorectifying WAC images.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Virador, Patrick R.G.
The author performs image reconstruction for a novel Positron Emission Tomography camera that is optimized for breast cancer imaging. This work addresses for the first time, the problem of fully-3D, tomographic reconstruction using a septa-less, stationary, (i.e. no rotation or linear motion), and rectangular camera whose Field of View (FOV) encompasses the entire volume enclosed by detector modules capable of measuring Depth of Interaction (DOI) information. The camera is rectangular in shape in order to accommodate breasts of varying sizes while allowing for soft compression of the breast during the scan. This non-standard geometry of the camera exacerbates two problems:more » (a) radial elongation due to crystal penetration and (b) reconstructing images from irregularly sampled data. Packing considerations also give rise to regions in projection space that are not sampled which lead to missing information. The author presents new Fourier Methods based image reconstruction algorithms that incorporate DOI information and accommodate the irregular sampling of the camera in a consistent manner by defining lines of responses (LORs) between the measured interaction points instead of rebinning the events into predefined crystal face LORs which is the only other method to handle DOI information proposed thus far. The new procedures maximize the use of the increased sampling provided by the DOI while minimizing interpolation in the data. The new algorithms use fixed-width evenly spaced radial bins in order to take advantage of the speed of the Fast Fourier Transform (FFT), which necessitates the use of irregular angular sampling in order to minimize the number of unnormalizable Zero-Efficiency Bins (ZEBs). In order to address the persisting ZEBs and the issue of missing information originating from packing considerations, the algorithms (a) perform nearest neighbor smoothing in 2D in the radial bins (b) employ a semi-iterative procedure in order to estimate the unsampled data and (c) mash the in plane projections, i.e. 2D data, with the projection data from the first oblique angles, which are then used to reconstruct the preliminary image in the 3D Reprojection Projection algorithm. The author presents reconstructed images of point sources and extended sources in both 2D and 3D. The images show that the camera is anticipated to eliminate radial elongation and produce artifact free and essentially spatially isotropic images throughout the entire FOV. It has a resolution of 1.50 ± 0.75 mm FWHM near the center, 2.25 ±0.75 mm FWHM in the bulk of the FOV, and 3.00 ± 0.75 mm FWHM near the edge and corners of the FOV.« less
NASA Technical Reports Server (NTRS)
2004-01-01
This image shows where Earth would set on the martian horizon from the perspective of the Mars Exploration Rover Spirit if it were facing northwest atop its lander at Gusev Crater. Earth cannot be seen in this image, but engineers have mapped its location. This image mosaic was taken by the hazard-identification camera onboard Spirit.
Picturing Leisure: Using Photovoice to Understand the Experience of Leisure and Dementia
ERIC Educational Resources Information Center
Genoe, M. Rebecca; Dupuis, Sherry L.
2013-01-01
Interviews and participant observation are commonly used to explore the experience of dementia, yet may not adequately capture perspectives of persons with dementia as communication changes. We used photovoice (i.e., using cameras in qualitative research) along with interviews and participant observation to explore meanings of leisure for persons…
Wearable Cameras as a Tool to Capture Preservice Teachers' Marked and Recorded Noticing
ERIC Educational Resources Information Center
Estapa, Anne; Amador, Julie
2016-01-01
Teacher educators use a multitude of technological sources to enhance teachers' learning. More specifically, many teacher educators incorporate video as a tool for supporting preservice teachers to analyze noticing of pivotal classroom interactions; however, this video is often from a perspective distinct from the teachers' view. This study…
Semi-autonomous wheelchair system using stereoscopic cameras.
Nguyen, Jordan S; Nguyen, Thanh H; Nguyen, Hung T
2009-01-01
This paper is concerned with the design and development of a semi-autonomous wheelchair system using stereoscopic cameras to assist hands-free control technologies for severely disabled people. The stereoscopic cameras capture an image from both the left and right cameras, which are then processed with a Sum of Absolute Differences (SAD) correlation algorithm to establish correspondence between image features in the different views of the scene. This is used to produce a stereo disparity image containing information about the depth of objects away from the camera in the image. A geometric projection algorithm is then used to generate a 3-Dimensional (3D) point map, placing pixels of the disparity image in 3D space. This is then converted to a 2-Dimensional (2D) depth map allowing objects in the scene to be viewed and a safe travel path for the wheelchair to be planned and followed based on the user's commands. This assistive technology utilising stereoscopic cameras has the purpose of automated obstacle detection, path planning and following, and collision avoidance during navigation. Experimental results obtained in an indoor environment displayed the effectiveness of this assistive technology.
NASA Astrophysics Data System (ADS)
Ratzloff, Jeff; Law, Nicholas M.; Fors, Octavi; Wulfken, Philip J.
2015-01-01
We designed, tested, prototyped and built a compact 27-camera robotic telescope that images 10,000 square degrees in 2-minute exposures. We exploit mass produced interline CCD Cameras with Rokinon consumer lenses to economically build a telescope that covers this large part of the sky simultaneously with a good enough pixel sampling to avoid the confusion limit over most of the sky. We developed the initial concept into a 3-d mechanical design with the aid of computer modeling programs. Significant design components include the camera assembly-mounting modules, the hemispherical support structure, and the instrument base structure. We simulated flexure and material stress in each of the three main components, which helped us optimize the rigidity and materials selection, while reducing weight. The camera mounts are CNC aluminum and the support shell is reinforced fiberglass. Other significant project components include optimizing camera locations, camera alignment, thermal analysis, environmental sealing, wind protection, and ease of access to internal components. The Evryscope will be assembled at UNC Chapel Hill and deployed to the CTIO in 2015.
Image system for three dimensional, 360 DEGREE, time sequence surface mapping of moving objects
Lu, Shin-Yee
1998-01-01
A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360.degree. all around coverage of theobject-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120.degree. apart from one another.
Image system for three dimensional, 360{degree}, time sequence surface mapping of moving objects
Lu, S.Y.
1998-12-22
A three-dimensional motion camera system comprises a light projector placed between two synchronous video cameras all focused on an object-of-interest. The light projector shines a sharp pattern of vertical lines (Ronchi ruling) on the object-of-interest that appear to be bent differently to each camera by virtue of the surface shape of the object-of-interest and the relative geometry of the cameras, light projector and object-of-interest. Each video frame is captured in a computer memory and analyzed. Since the relative geometry is known and the system pre-calibrated, the unknown three-dimensional shape of the object-of-interest can be solved for by matching the intersections of the projected light lines with orthogonal epipolar lines corresponding to horizontal rows in the video camera frames. A surface reconstruction is made and displayed on a monitor screen. For 360{degree} all around coverage of the object-of-interest, two additional sets of light projectors and corresponding cameras are distributed about 120{degree} apart from one another. 20 figs.
ENGINEERING TEST REACTOR (ETR) BUILDING, TRA642. CONTEXTUAL VIEW, CAMERA FACING ...
ENGINEERING TEST REACTOR (ETR) BUILDING, TRA-642. CONTEXTUAL VIEW, CAMERA FACING EAST. VERTICAL METAL SIDING. ROOF IS SLIGHTLY ELEVATED AT CENTER LINE FOR DRAINAGE. WEST SIDE OF ETR COMPRESSOR BUILDING, TRA-643, PROJECTS TOWARD LEFT AT FAR END OF ETR BUILDING. INL NEGATIVE NO. HD46-37-1. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
Support for the Naval Research Laboratory Environmental Passive Microwave Remote Sensing Program.
1983-04-29
L. H. Gesell te _ C= Project Manager ’ . . , . ".."........... . ., . q J ABSTRACT This document summarizes the data acquisition, reduc- tion, and...film camera , and other environmental sensors. CSC gradually assumed the bulk of the responsibility for opera- ting this equipment. This included running...radiometers, and setting up and operating the strip-film camera and other en- vironmental sensors. Also of significant importance to the missions was
Li, James C. M.; Chu, Sungnee G.
1980-01-01
A hemispherical Laue camera comprises a crystal sample mount for positioning a sample to be analyzed at the center of sphere of a hemispherical, X-radiation sensitive film cassette, a collimator, a stationary or rotating sample mount and a set of standard spherical projection spheres. X-radiation generated from an external source is directed through the collimator to impinge onto the single crystal sample on the stationary mount. The diffracted beam is recorded on the hemispherical X-radiation sensitive film mounted inside the hemispherical film cassette in either transmission or back-reflection geometry. The distances travelled by X-radiation diffracted from the crystal to the hemispherical film are the same for all crystal planes which satisfy Bragg's Law. The recorded diffraction spots or Laue spots on the film thereby preserve both the symmetry information of the crystal structure and the relative intensities which are directly related to the relative structure factors of the crystal orientations. The diffraction pattern on the exposed film is compared with the known diffraction pattern on one of the standard spherical projection spheres for a specific crystal structure to determine the orientation of the crystal sample. By replacing the stationary sample support with a rotating sample mount, the hemispherical Laue camera can be used for crystal structure determination in a manner previously provided in conventional Debye-Scherrer cameras.
Spatial calibration of an optical see-through head mounted display
Gilson, Stuart J.; Fitzgibbon, Andrew W.; Glennerster, Andrew
2010-01-01
We present here a method for calibrating an optical see-through Head Mounted Display (HMD) using techniques usually applied to camera calibration (photogrammetry). Using a camera placed inside the HMD to take pictures simultaneously of a tracked object and features in the HMD display, we could exploit established camera calibration techniques to recover both the intrinsic and extrinsic properties of the HMD (width, height, focal length, optic centre and principal ray of the display). Our method gives low re-projection errors and, unlike existing methods, involves no time-consuming and error-prone human measurements, nor any prior estimates about the HMD geometry. PMID:18599125
The Large Synoptic Survey Telescope (LSST) Camera
None
2018-06-13
Ranked as the top ground-based national priority for the field for the current decade, LSST is currently under construction in Chile. The U.S. Department of Energyâs SLAC National Accelerator Laboratory is leading the construction of the LSST camera â the largest digital camera ever built for astronomy. SLAC Professor Steven M. Kahn is the overall Director of the LSST project, and SLAC personnel are also participating in the data management. The National Science Foundation is the lead agency for construction of the LSST. Additional financial support comes from the Department of Energy and private funding raised by the LSST Corporation.
C-RED one: ultra-high speed wavefront sensing in the infrared made possible
NASA Astrophysics Data System (ADS)
Gach, J.-L.; Feautrier, Philippe; Stadler, Eric; Greffe, Timothee; Clop, Fabien; Lemarchand, Stéphane; Carmignani, Thomas; Boutolleau, David; Baker, Ian
2016-07-01
First Light Imaging's CRED-ONE infrared camera is capable of capturing up to 3500 full frames per second with a subelectron readout noise. This breakthrough has been made possible thanks to the use of an e-APD infrared focal plane array which is a real disruptive technology in imagery. We will show the performances of the camera, its main features and compare them to other high performance wavefront sensing cameras like OCAM2 in the visible and in the infrared. The project leading to this application has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement N° 673944.
NASA Astrophysics Data System (ADS)
Soliz, Peter; Nemeth, Sheila C.; Barriga, E. Simon; Harding, Simon P.; Lewallen, Susan; Taylor, Terrie E.; MacCormick, Ian J.; Joshi, Vinayak S.
2016-03-01
The purpose of this study was to test the suitability of three available camera technologies (desktop, portable, and iphone based) for imaging comatose children who presented with clinical symptoms of malaria. Ultimately, the results of the project would form the basis for a design of a future camera to screen for malaria retinopathy (MR) in a resource challenged environment. The desktop, portable, and i-phone based cameras were represented by the Topcon, Pictor Plus, and Peek cameras, respectively. These cameras were tested on N=23 children presenting with symptoms of cerebral malaria (CM) at a malaria clinic, Queen Elizabeth Teaching Hospital in Malawi, Africa. Each patient was dilated for binocular indirect ophthalmoscopy (BIO) exam by an ophthalmologist followed by imaging with all three cameras. Each of the cases was graded according to an internationally established protocol and compared to the BIO as the clinical ground truth. The reader used three principal retinal lesions as markers for MR: hemorrhages, retinal whitening, and vessel discoloration. The study found that the mid-priced Pictor Plus hand-held camera performed considerably better than the lower price mobile phone-based camera, and slightly the higher priced table top camera. When comparing the readings of digital images against the clinical reference standard (BIO), the Pictor Plus camera had sensitivity and specificity for MR of 100% and 87%, respectively. This compares to a sensitivity and specificity of 87% and 75% for the i-phone based camera and 100% and 75% for the desktop camera. The drawback of all the cameras were their limited field of view which did not allow complete view of the periphery where vessel discoloration occurs most frequently. The consequence was that vessel discoloration was not addressed in this study. None of the cameras offered real-time image quality assessment to ensure high quality images to afford the best possible opportunity for reading by a remotely located specialist.
Lights, Camera, Project-Based Learning!
ERIC Educational Resources Information Center
Cox, Dannon G.; Meaney, Karen S.
2018-01-01
A physical education instructor incorporates a teaching method known as project-based learning (PBL) in his physical education curriculum. Utilizing video-production equipment to imitate the production of a televisions show, sixth-grade students attending a charter school invited college students to share their stories about physical activity and…
NASA Astrophysics Data System (ADS)
Liu, Guannan; Liu, Dong
2018-05-01
Not Available Project supported by the National Natural Science Foundation of China (Grant No. 51576100) and the Project of “Six Talent Summit” of Jiangsu Province, China (Grant No. 2014-XNY-002).
DOT National Transportation Integrated Search
2013-10-01
This study will evaluate the video detection technologies currently adopted by the city : of Baton Rouge, LA, and DOTD with the purpose of establishing design guidelines based : on the detection needs, functionality, and cost. The study will also dev...
Perspective traffic display format and airline pilot traffic avoidance
NASA Technical Reports Server (NTRS)
Ellis, Stephen R.; Mcgreevy, Michael W.; Hitchcock, Robert J.
1987-01-01
Part-task experiments have examined perspective projections of cockpit displays of traffic information as a means of presenting aircraft separation information to airline pilots. Ten airline pilots served as subjects in an experiment comparing the perspective projection with plan-view projections of the same air traffic situations. The pilots' task was to monitor the traffic display in order to decide if an avoidance maneuver was needed. Pilots took more time to select avoidance maneuvers with a conventional plan-view display than with an experimental perspective display. In contrast to previous results, if the pilots selected a maneuver with the perspective display, they were more likely to choose one with a vertical component. Tabulation of the outcomes of their initial avoidance decisions with both perspective and plan-view displays showed that they were more likely to achieve required separation with maneuvers chosen with the aid of perspective displays.
ERIC Educational Resources Information Center
Tomash, Lisa
2010-01-01
In this article, the author describes a landscape project using Grant Wood's paintings as an example. As part of the project, the students are required to include a barn in their picture. This project is a great opportunity to study an Iowa artist who did landscape painting and to study perspective. This is also an excellent project for teaching…
D Modelling with the Samsung Gear 360
NASA Astrophysics Data System (ADS)
Barazzetti, L.; Previtali, M.; Roncoroni, F.
2017-02-01
The Samsung Gear 360 is a consumer grade spherical camera able to capture photos and videos. The aim of this work is to test the metric accuracy and the level of detail achievable with the Samsung Gear 360 coupled with digital modelling techniques based on photogrammetry/computer vision algorithms. Results demonstrate that the direct use of the projection generated inside the mobile phone or with Gear 360 Action Direction (the desktop software for post-processing) have a relatively low metric accuracy. As results were in contrast with the accuracy achieved by using the original fisheye images (front and rear facing images) in photogrammetric reconstructions, an alternative solution to generate the equirectangular projections was developed. A calibration aimed at understanding the intrinsic parameters of the two lenses camera, as well as their relative orientation, allowed one to generate new equirectangular projections from which a significant improvement of geometric accuracy has been achieved.
A CCD Spectrometer for One Dollar
NASA Astrophysics Data System (ADS)
Beaver, J.; Robert, D.
2011-09-01
We describe preliminary tests on a very low-cost system for obtaining stellar spectra for instructional use in an introductory astronomy laboratory. CCD imaging with small telescopes is now commonplace and relatively inexpensive. Giving students direct experience taking stellar spectra, however, is much more difficult, and the equipment can easily be out of reach for smaller institutions, especially if one wants to give the experience to large numbers of students. We have performed preliminary tests on an extremely low-cost (about $1.00) objective grating that can be coupled with an existing CCD camera or commercial digital single-lens reflex (DSLR) camera and a small telescope typical of introductory astronomy labs. With this equipment we believe it is possible for introductory astronomy students to take stellar spectra that are of high enough quality to distinguish between many MK spectral classes, or to determine standard B and V magnitudes. We present observational tests of this objective grating used on an 8" Schmidt-Cassegrain with a low-end, consumer DSLR camera. Some low-cost strategies for reducing the raw data are compared, with an eye toward projects ranging from individual undergraduate research projects to use by many students in a non-majors introductory astronomy lab. Toward this end we compare various trade offs between complexity of the observing and data reduction processes and the usefulness of the final results. We also describe some undergraduate astronomy education projects that this system could potentially be used for. Some of these projects could involve data-sharing collaborations between students at different institutions.
NASA Astrophysics Data System (ADS)
Basoglu, Burak; Halicioglu, Kerem; Albayrak, Muge; Ulug, Rasit; Tevfik Ozludemir, M.; Deniz, Rasim
2017-04-01
In the last decade, the importance of high-precise geoid determination at local or national level has been pointed out by Turkish National Geodesy Commission. The Commission has also put objective of modernization of national height system of Turkey to the agenda. Meanwhile several projects have been realized in recent years. In Istanbul city, a GNSS/Levelling geoid was defined in 2005 for the metropolitan area of the city with an accuracy of ±3.5cm. In order to achieve a better accuracy in this area, "Local Geoid Determination with Integration of GNSS/Levelling and Astro-Geodetic Data" project has been conducted in Istanbul Technical University and Bogazici University KOERI since January 2016. The project is funded by The Scientific and Technological Research Council of Turkey. With the scope of the project, modernization studies of Digital Zenith Camera System are being carried on in terms of hardware components and software development. Accentuated subjects are the star catalogues, and centroiding algorithm used to identify the stars on the zenithal star field. During the test observations of Digital Zenith Camera System performed between 2013-2016, final results were calculated using the PSF method for star centroiding, and the second USNO CCD Astrograph Catalogue (UCAC2) for the reference star positions. This study aims to investigate the position accuracy of the star images by comparing different centroiding algorithms and available star catalogs used in astro-geodetic observations conducted with the digital zenith camera system.
ERIC Educational Resources Information Center
Physics Education, 1988
1988-01-01
Described are five physics activities including two superconductor projects, synchronizing video camera movements, electrical analysis of a bicycle, and apparatus for the measurement of thermal conductivity. (YP)
Charge Diffusion Variations in Pan-STARRS1 CCDs
NASA Astrophysics Data System (ADS)
Magnier, Eugene A.; Tonry, J. L.; Finkbeiner, D.; Schlafly, E.; Burgett, W. S.; Chambers, K. C.; Flewelling, H. A.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Metcalfe, N.; Wainscoat, R. J.; Waters, C. Z.
2018-06-01
Thick back-illuminated deep-depletion CCDs have superior quantum efficiency over previous generations of thinned and traditional thick CCDs. As a result, they are being used for wide-field imaging cameras in several major projects. We use observations from the Pan-STARRS 3π survey to characterize the behavior of the deep-depletion devices used in the Pan-STARRS 1 Gigapixel Camera. We have identified systematic spatial variations in the photometric measurements and stellar profiles that are similar in pattern to the so-called “tree rings” identified in devices used by other wide-field cameras (e.g., DECam and Hypersuprime Camera). The tree-ring features identified in these other cameras result from lateral electric fields that displace the electrons as they are transported in the silicon to the pixel location. In contrast, we show that the photometric and morphological modifications observed in the GPC1 detectors are caused by variations in the vertical charge transportation rate and resulting charge diffusion variations.
A four-lens based plenoptic camera for depth measurements
NASA Astrophysics Data System (ADS)
Riou, Cécile; Deng, Zhiyuan; Colicchio, Bruno; Lauffenburger, Jean-Philippe; Kohler, Sophie; Haeberlé, Olivier; Cudel, Christophe
2015-04-01
In previous works, we have extended the principles of "variable homography", defined by Zhang and Greenspan, for measuring height of emergent fibers on glass and non-woven fabrics. This method has been defined for working with fabric samples progressing on a conveyor belt. Triggered acquisition of two successive images was needed to perform the 3D measurement. In this work, we have retained advantages of homography variable for measurements along Z axis, but we have reduced acquisitions number to a single one, by developing an acquisition device characterized by 4 lenses placed in front of a single image sensor. The idea is then to obtain four projected sub-images on a single CCD sensor. The device becomes a plenoptic or light field camera, capturing multiple views on the same image sensor. We have adapted the variable homography formulation for this device and we propose a new formulation to calculate a depth with plenoptic cameras. With these results, we have transformed our plenoptic camera in a depth camera and first results given are very promising.
Wide Field and Planetary Camera for Space Telescope
NASA Technical Reports Server (NTRS)
Lockhart, R. F.
1982-01-01
The Space Telescope's Wide Field and Planetary Camera instrument, presently under construction, will be used to map the observable universe and to study the outer planets. It will be able to see 1000 times farther than any previously employed instrument. The Wide Field system will be located in a radial bay, receiving its signals via a pick-off mirror centered on the optical axis of the telescope assembly. The external thermal radiator employed by the instrument for cooling will be part of the exterior surface of the Space Telescope. In addition to having a larger (1200-12,000 A) wavelength range than any of the other Space Telescope instruments, its data rate, at 1 Mb/sec, exceeds that of the other instruments. Attention is given to the operating modes and projected performance levels of the Wide Field Camera and Planetary Camera.
Xu, Guan; Yuan, Jing; Li, Xiaotao; Su, Jian
2017-08-01
Vision measurement on the basis of structured light plays a significant role in the optical inspection research. The 2D target fixed with a line laser projector is designed to realize the transformations among the world coordinate system, the camera coordinate system and the image coordinate system. The laser projective point and five non-collinear points that are randomly selected from the target are adopted to construct a projection invariant. The closed form solutions of the 3D laser points are solved by the homogeneous linear equations generated from the projection invariants. The optimization function is created by the parameterized re-projection errors of the laser points and the target points in the image coordinate system. Furthermore, the nonlinear optimization solutions of the world coordinates of the projection points, the camera parameters and the lens distortion coefficients are contributed by minimizing the optimization function. The accuracy of the 3D reconstruction is evaluated by comparing the displacements of the reconstructed laser points with the actual displacements. The effects of the image quantity, the lens distortion and the noises are investigated in the experiments, which demonstrate that the reconstruction approach is effective to contribute the accurate test in the measurement system.
Signal Collection Processing Enhancements
2004-04-01
APPROVED: /s/ ALFREDO VEGA IRIZARRY Project Engineer FOR THE DIRECTOR: /s/ JOSEPH CAMERA, Chief...SPONSORING / MONITORING AGENCY REPORT NUMBER AFRL-IF-RS-TR-2004-108 11. SUPPLEMENTARY NOTES AFRL Project Engineer: Alfredo Vega Irizzary...Mercury representative, Emilio Velilla, suggested several actions to better diagnose the problem. Both boards were moved to different PCI slots. The
2012-06-25
A frame grab from a mounted video camera on the E-3 Test Stand at Stennis Space Center documents testing of the new Project Morpheus engine. The new liquid methane, liquid oxygen engine will power the Morpheus prototype lander, which could one day evolve to carry cargo safely to the moon, asteroids or Mars surfaces.
"Immersive Education" Submerges Students in Online Worlds Made for Learning
ERIC Educational Resources Information Center
Foster, Andrea L.
2007-01-01
Immersive Education is a multimillion-dollar project devoted to build virtual-reality software exclusively for education within commercial and nonprofit fantasy spaces like Second Life. The project combines interactive three-dimensional graphics, Web cameras, Internet-based telephony, and other digital media. Some critics have complained that…
Production application of injection-molded diffractive elements
NASA Astrophysics Data System (ADS)
Clark, Peter P.; Chao, Yvonne Y.; Hines, Kevin P.
1995-12-01
We demonstrate that transmission kinoforms for visible light applications can be injection molded in acrylic in production volumes. A camera is described that employs molded Fresnel lenses to change the convergence of a projection ranging system. Kinoform surfaces are used in the projection system to achromatize the Fresnel lenses.
A&M. TAN607. Southern sections added in expansion project of 1957. ...
A&M. TAN-607. Southern sections added in expansion project of 1957. Camera facing northwest. Concrete decontamination section on left end. Photographer: Jack L. Anderson. Date: October 23, 1957. INEEL negative no. 57-5337 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID
The soft embodiment of culture: camera angles and motion through time and space.
Leung, Angela K-y; Cohen, Dov
2007-09-01
Cultural assumptions about one's relation to others and one's place in the world can be literally embodied in the way one cognitively maps out one's position and motion in time and space. In three experiments, we examined the psychological perspective that Asian American and Euro-American participants embodied as they both comprehended and produced narratives and mapped out metaphors of time and space. In social situations, Euro-American participants were more likely to embody their own perspective and a sense of their own motion (rather than those of a friend), whereas Asian American participants were more likely to embody a friend's perspective and sense of motion (rather than their own). We discuss how these psychological perspectives represent the soft embodiment of culture by implicitly instantiating cultural injunctions (a) to think about how you look to others and to harmonize with them or (b) to know yourself, trust yourself, and act with confidence.
Video Capture of Plastic Surgery Procedures Using the GoPro HERO 3+
Graves, Steven Nicholas; Shenaq, Deana Saleh; Langerman, Alexander J.
2015-01-01
Background: Significant improvements can be made in recoding surgical procedures, particularly in capturing high-quality video recordings from the surgeons’ point of view. This study examined the utility of the GoPro HERO 3+ Black Edition camera for high-definition, point-of-view recordings of plastic and reconstructive surgery. Methods: The GoPro HERO 3+ Black Edition camera was head-mounted on the surgeon and oriented to the surgeon’s perspective using the GoPro App. The camera was used to record 4 cases: 2 fat graft procedures and 2 breast reconstructions. During cases 1-3, an assistant remotely controlled the GoPro via the GoPro App. For case 4 the GoPro was linked to a WiFi remote, and controlled by the surgeon. Results: Camera settings for case 1 were as follows: 1080p video resolution; 48 fps; Protune mode on; wide field of view; 16:9 aspect ratio. The lighting contrast due to the overhead lights resulted in limited washout of the video image. Camera settings were adjusted for cases 2-4 to a narrow field of view, which enabled the camera’s automatic white balance to better compensate for bright lights focused on the surgical field. Cases 2-4 captured video sufficient for teaching or presentation purposes. Conclusions: The GoPro HERO 3+ Black Edition camera enables high-quality, cost-effective video recording of plastic and reconstructive surgery procedures. When set to a narrow field of view and automatic white balance, the camera is able to sufficiently compensate for the contrasting light environment of the operating room and capture high-resolution, detailed video. PMID:25750851
Computational photography with plenoptic camera and light field capture: tutorial.
Lam, Edmund Y
2015-11-01
Photography is a cornerstone of imaging. Ever since cameras became consumer products more than a century ago, we have witnessed great technological progress in optics and recording mediums, with digital sensors replacing photographic films in most instances. The latest revolution is computational photography, which seeks to make image reconstruction computation an integral part of the image formation process; in this way, there can be new capabilities or better performance in the overall imaging system. A leading effort in this area is called the plenoptic camera, which aims at capturing the light field of an object; proper reconstruction algorithms can then adjust the focus after the image capture. In this tutorial paper, we first illustrate the concept of plenoptic function and light field from the perspective of geometric optics. This is followed by a discussion on early attempts and recent advances in the construction of the plenoptic camera. We will then describe the imaging model and computational algorithms that can reconstruct images at different focus points, using mathematical tools from ray optics and Fourier optics. Last, but not least, we will consider the trade-off in spatial resolution and highlight some research work to increase the spatial resolution of the resulting images.
Passive stand-off terahertz imaging with 1 hertz frame rate
NASA Astrophysics Data System (ADS)
May, T.; Zieger, G.; Anders, S.; Zakosarenko, V.; Starkloff, M.; Meyer, H.-G.; Thorwirth, G.; Kreysa, E.
2008-04-01
Terahertz (THz) cameras are expected to be a powerful tool for future security applications. If such a technology shall be useful for typical security scenarios (e.g. airport check-in) it has to meet some minimum standards. A THz camera should record images with video rate from a safe distance (stand-off). Although active cameras are conceivable, a passive system has the benefit of concealed operation. Additionally, from an ethic perspective, the lack of exposure to a radiation source is a considerable advantage in public acceptance. Taking all these requirements into account, only cooled detectors are able to achieve the needed sensitivity. A big leap forward in the detector performance and scalability was driven by the astrophysics community. Superconducting bolometers and midsized arrays of them have been developed and are in routine use. Although devices with many pixels are foreseeable nowadays a device with an additional scanning optic is the straightest way to an imaging system with a useful resolution. We demonstrate the capabilities of a concept for a passive Terahertz video camera based on superconducting technology. The actual prototype utilizes a small Cassegrain telescope with a gyrating secondary mirror to record 2 kilopixel THz images with 1 second frame rate.
Plenoptic PIV: Towards simple, robust 3D flow measurements
NASA Astrophysics Data System (ADS)
Thurow, Brian; Fahringer, Tim
2013-11-01
In this work, we report on the recent development of plenoptic PIV for the measurement of 3D flow fields. Plenoptic PIV uses a plenoptic camera to record the 4D light-field generated by a volume of particles seeded into a flow field. Plenoptic cameras are primarily known for their ability to computational refocus or change the perspective of an image after it has been acquired. In this work, we use tomographic algorithms to reconstruct a 3D volume of the particle field and apply a cross-correlation algorithm to a pair of particle volumes to determine the 3D/3C velocity field. The primary advantage of plenoptic PIV over multi-camera techniques is that it only uses a single camera, which greatly reduces the cost and simplifies a typical experimental arrangement. In addition, plenoptic PIV is capable of making measurements over dimensions on the order of 100 mm × 100 mm × 100 mm. The spatial resolution and accuracy of the technique are presented along with examples of 3D velocity data acquired in turbulent boundary layers and supersonic jets. This work was primarily supported through an AFOSR grant.
A DirtI Application for LBT Commissioning Campaigns
NASA Astrophysics Data System (ADS)
Borelli, J. L.
2009-09-01
In order to characterize the Gregorian focal stations and test the performance achieved by the Large Binocular Telescope (LBT) adaptive optics system, two infrared test cameras were constructed within a joint project between INAF (Observatorio Astronomico di Bologna, Italy) and the Max Planck Institute for Astronomy (Germany). Is intended here to describe the functionality and successful results obtained with the Daemon for the Infrared Test Camera Interface (DirtI) during commissioning campaigns.
Polarimetry at millimeter wavelengths with the NIKA camera: calibration and performance
NASA Astrophysics Data System (ADS)
Ritacco, A.; Ponthieu, N.; Catalano, A.; Adam, R.; Ade, P.; André, P.; Beelen, A.; Benoît, A.; Bideaud, A.; Billot, N.; Bourrion, O.; Calvo, M.; Coiffard, G.; Comis, B.; Désert, F.-X.; Doyle, S.; Goupy, J.; Kramer, C.; Leclercq, S.; Macías-Pérez, J. F.; Mauskopf, P.; Maury, A.; Mayet, F.; Monfardini, A.; Pajot, F.; Pascale, E.; Perotto, L.; Pisano, G.; Rebolo-Iglesias, M.; Revéret, V.; Rodriguez, L.; Romero, C.; Ruppin, F.; Savini, G.; Schuster, K.; Sievers, A.; Thum, C.; Triqueneaux, S.; Tucker, C.; Zylka, R.
2017-03-01
Magnetic fields, which play a major role in a large number of astrophysical processes can be traced via observations of dust polarization. In particular, Planck low-resolution observations of dust polarization have demonstrated that Galactic filamentary structures, where star formation takes place, are associated to well organized magnetic fields. A better understanding of this process requires detailed observations of galactic dust polarization on scales of 0.01 to 0.1 pc. Such high-resolution polarization observations can be carried out at the IRAM 30 m telescope using the recently installed NIKA2 camera, which features two frequency bands at 260 and 150 GHz (respectively 1.15 and 2.05 mm), the 260 GHz band being polarization sensitive. NIKA2 so far in commissioning phase, has its focal plane filled with 3300 detectors to cover a Field of View (FoV) of 6.5 arcmin diameter. The NIKA camera, which consisted of two arrays of 132 and 224 Lumped Element Kinetic Inductance Detectors (LEKIDs) and a FWHM (Full-Width-Half-Maximum) of 12 and 18.2 arcsec at 1.15 and 2.05 mm respectively, has been operated at the IRAM 30 m telescope from 2012 to 2015 as a test-bench for NIKA2. NIKA was equipped of a room temperature polarization system (a half wave plate (HWP) and a grid polarizer facing the NIKA cryostat window). The fast and continuous rotation of the HWP permits the quasi simultaneous reconstruction of the three Stokes parameters, I, Q, and U at 150 and 260 GHz. This paper presents the first polarization measurements with KIDs and reports the polarization performance of the NIKA camera and the pertinence of the choice of the polarization setup in the perspective of NIKA2. We describe the polarized data reduction pipeline, specifically developed for this project and how the continuous rotation of the HWP permits to shift the polarized signal far from any low frequency noise. We also present the dedicated algorithm developed to correct systematic leakage effects. We report results on compact and extended sources obtained duringthe February 2015 technical campaign. These results demonstrate a good understanding of polarization systematics and state-of-the-art performance in terms of photometry, polarization degree and polarization angle reconstruction.
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.
Automatic Camera Calibration for Cultural Heritage Applications Using Unstructured Planar Objects
NASA Astrophysics Data System (ADS)
Adam, K.; Kalisperakis, I.; Grammatikopoulos, L.; Karras, G.; Petsa, E.
2013-07-01
As a rule, image-based documentation of cultural heritage relies today on ordinary digital cameras and commercial software. As such projects often involve researchers not familiar with photogrammetry, the question of camera calibration is important. Freely available open-source user-friendly software for automatic camera calibration, often based on simple 2D chess-board patterns, are an answer to the demand for simplicity and automation. However, such tools cannot respond to all requirements met in cultural heritage conservation regarding possible imaging distances and focal lengths. Here we investigate the practical possibility of camera calibration from unknown planar objects, i.e. any planar surface with adequate texture; we have focused on the example of urban walls covered with graffiti. Images are connected pair-wise with inter-image homographies, which are estimated automatically through a RANSAC-based approach after extracting and matching interest points with the SIFT operator. All valid points are identified on all images on which they appear. Provided that the image set includes a "fronto-parallel" view, inter-image homographies with this image are regarded as emulations of image-to-world homographies and allow computing initial estimates for the interior and exterior orientation elements. Following this initialization step, the estimates are introduced into a final self-calibrating bundle adjustment. Measures are taken to discard unsuitable images and verify object planarity. Results from practical experimentation indicate that this method may produce satisfactory results. The authors intend to incorporate the described approach into their freely available user-friendly software tool, which relies on chess-boards, to assist non-experts in their projects with image-based approaches.
The prototype cameras for trans-Neptunian automatic occultation survey
NASA Astrophysics Data System (ADS)
Wang, Shiang-Yu; Ling, Hung-Hsu; Hu, Yen-Sang; Geary, John C.; Chang, Yin-Chang; Chen, Hsin-Yo; Amato, Stephen M.; Huang, Pin-Jie; Pratlong, Jerome; Szentgyorgyi, Andrew; Lehner, Matthew; Norton, Timothy; Jorden, Paul
2016-08-01
The Transneptunian Automated Occultation Survey (TAOS II) is a three robotic telescope project to detect the stellar occultation events generated by TransNeptunian Objects (TNOs). TAOS II project aims to monitor about 10000 stars simultaneously at 20Hz to enable statistically significant event rate. The TAOS II camera is designed to cover the 1.7 degrees diameter field of view of the 1.3m telescope with 10 mosaic 4.5k×2k CMOS sensors. The new CMOS sensor (CIS 113) has a back illumination thinned structure and high sensitivity to provide similar performance to that of the back-illumination thinned CCDs. Due to the requirements of high performance and high speed, the development of the new CMOS sensor is still in progress. Before the science arrays are delivered, a prototype camera is developed to help on the commissioning of the robotic telescope system. The prototype camera uses the small format e2v CIS 107 device but with the same dewar and also the similar control electronics as the TAOS II science camera. The sensors, mounted on a single Invar plate, are cooled to the operation temperature of about 200K as the science array by a cryogenic cooler. The Invar plate is connected to the dewar body through a supporting ring with three G10 bipods. The control electronics consists of analog part and a Xilinx FPGA based digital circuit. One FPGA is needed to control and process the signal from a CMOS sensor for 20Hz region of interests (ROI) readout.
Spherical Images for Cultural Heritage: Survey and Documentation with the Nikon KM360
NASA Astrophysics Data System (ADS)
Gottardi, C.; Guerra, F.
2018-05-01
The work presented here focuses on the analysis of the potential of spherical images acquired with specific cameras for documentation and three-dimensional reconstruction of Cultural Heritage. Nowadays, thanks to the introduction of cameras able to generate panoramic images automatically, without the requirement of a stitching software to join together different photos, spherical images allow the documentation of spaces in an extremely fast and efficient way. In this particular case, the Nikon Key Mission 360 spherical camera was tested on the Tolentini's cloister, which used to be part of the convent of the close church and now location of the Iuav University of Venice. The aim of the research is based on testing the acquisition of spherical images with the KM360 and comparing the obtained photogrammetric models with data acquired from a laser scanning survey in order to test the metric accuracy and the level of detail achievable with this particular camera. This work is part of a wider research project that the Photogrammetry Laboratory of the Iuav University of Venice has been dealing with in the last few months; the final aim of this research project will be not only the comparison between 3D models obtained from spherical images and laser scanning survey's techniques, but also the examination of their reliability and accuracy with respect to the previous methods of generating spherical panoramas. At the end of the research work, we would like to obtain an operational procedure for spherical cameras applied to metric survey and documentation of Cultural Heritage.
ERIC Educational Resources Information Center
Davis, Heather A.; Summers, Jessica J.; Miller, Lauren M.
2012-01-01
Like having a hidden camera in other teachers' classrooms, An Interpersonal Approach to Classroom Management engages you from the start by contrasting how two teachers respond differently to common situations. The authors expertly bridge the gap between educational psychology and peer and student-teacher management from the perspectives of student…
2009-06-25
61A-200-003 (30 Oct 1985) --- A large format Linhof camera onboard the Space Shuttle Columbia provided this coastal view of Somalia. The perspective is looking north from Muqdisho (foreground) to Raas Xaafuun at the horizon. Cumulus clouds cover the Somali Desert. The elongated, thinner steak of clouds follows a topographically depressed area, a wash know as Webi Shibeli.
1999-08-25
Mosaic of Triton constructed from 16 individual images. After globally minimizing the camera pointing errors, the frames we reprocessed by map projections, photometric function removal and placement in the mosaic.
Full-parallax 3D display from stereo-hybrid 3D camera system
NASA Astrophysics Data System (ADS)
Hong, Seokmin; Ansari, Amir; Saavedra, Genaro; Martinez-Corral, Manuel
2018-04-01
In this paper, we propose an innovative approach for the production of the microimages ready to display onto an integral-imaging monitor. Our main contribution is using a stereo-hybrid 3D camera system, which is used for picking up a 3D data pair and composing a denser point cloud. However, there is an intrinsic difficulty in the fact that hybrid sensors have dissimilarities and therefore should be equalized. Handled data facilitate to generating an integral image after projecting computationally the information through a virtual pinhole array. We illustrate this procedure with some imaging experiments that provide microimages with enhanced quality. After projection of such microimages onto the integral-imaging monitor, 3D images are produced with great parallax and viewing angle.
Spirit's View Beside 'Home Plate' on Sol 1823 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11971 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11971 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,823rd Martian day, or sol, of Spirit's surface mission (Feb. 17, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The center of the view is toward the south-southwest. The rover had driven 7 meters (23 feet) eastward earlier on Sol 1823, part of maneuvering to get Spirit into a favorable position for climbing onto the low plateau called 'Home Plate.' However, after two driving attempts with negligible progress during the following three sols, the rover team changed its strategy for getting to destinations south of Home Plate. The team decided to drive Spirit at least partway around Home Plate, instead of ascending the northern edge and taking a shorter route across the top of the plateau. Layered rocks forming part of the northern edge of Home Plate can be seen near the center of the image. Rover wheel tracks are visible at the lower edge. This view is presented as a cylindrical-perspective projection with geometric seam correction.New Record Five-Wheel Drive, Spirit's Sol 1856 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11962 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11962 NASA's Mars Exploration Rover Spirit used its navigation camera to take the images that have been combined into this stereo, 180-degree view of the rover's surroundings during the 1,856th Martian day, or sol, of Spirit's surface mission (March 23, 2009). The center of the view is toward the west-southwest. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The rover had driven 25.82 meters (84.7 feet) west-northwestward earlier on Sol 1856. This is the longest drive on Mars so far by a rover using only five wheels. Spirit lost the use of its right-front wheel in March 2006. Before Sol 1856, the farthest Spirit had covered in a single sol's five-wheel drive was 24.83 meters (81.5 feet), on Sol 1363 (Nov. 3, 2007). The Sol 1856 drive made progress on a route planned for taking Spirit around the western side of the low plateau called 'Home Plate.' A portion of the northwestern edge of Home Plate is prominent in the left quarter of this image, toward the south. This view is presented as a cylindrical-perspective projection with geometric seam correction.Using turbulence scintillation to assist object ranging from a single camera viewpoint.
Wu, Chensheng; Ko, Jonathan; Coffaro, Joseph; Paulson, Daniel A; Rzasa, John R; Andrews, Larry C; Phillips, Ronald L; Crabbs, Robert; Davis, Christopher C
2018-03-20
Image distortions caused by atmospheric turbulence are often treated as unwanted noise or errors in many image processing studies. Our study, however, shows that in certain scenarios the turbulence distortion can be very helpful in enhancing image processing results. This paper describes a novel approach that uses the scintillation traits recorded on a video clip to perform object ranging with reasonable accuracy from a single camera viewpoint. Conventionally, a single camera would be confused by the perspective viewing problem, where a large object far away looks the same as a small object close by. When the atmospheric turbulence phenomenon is considered, the edge or texture pixels of an object tend to scintillate and vary more with increased distance. This turbulence induced signature can be quantitatively analyzed to achieve object ranging with reasonable accuracy. Despite the inevitable fact that turbulence will cause random blurring and deformation of imaging results, it also offers convenient solutions to some remote sensing and machine vision problems, which would otherwise be difficult.
NASA Astrophysics Data System (ADS)
Koskelo, Elise Anne C.; Flynn, Eric B.
2017-02-01
Inspection of and around joints, beams, and other three-dimensional structures is integral to practical nondestructive evaluation of large structures. Non-contact, scanning laser ultrasound techniques offer an automated means of physically accessing these regions. However, to realize the benefits of laser-scanning techniques, simultaneous inspection of multiple surfaces at different orientations to the scanner must not significantly degrade the signal level nor diminish the ability to distinguish defects from healthy geometric features. In this study, we evaluated the implementation of acoustic wavenumber spectroscopy for inspecting metal joints and crossbeams from interior angles. With this technique, we used a single-tone, steady-state, ultrasonic excitation to excite the joints via a single transducer attached to one surface. We then measured the full-field velocity responses using a scanning Laser Doppler vibrometer and produced maps of local wavenumber estimates. With the high signal level associated with steady-state excitation, scans could be performed at surface orientations of up to 45 degrees. We applied camera perspective projection transformations to remove the distortion in the scans due to a known projection angle, leading to a significant improvement in the local estimates of wavenumber. Projection leads to asymmetrical distortion in the wavenumber in one direction, making it possible to estimate view angle even when neither it nor the nominal wavenumber is known. Since plate thinning produces a purely symmetric increase in wavenumber, it also possible to independently estimate the degree of hidden corrosion. With a two-surface joint, using the wavenumber estimate maps, we were able to automatically calculate the orthographic projection component of each angled surface in the scan area.
The kinelite project. A new powerful motion analyser for spacelab and space station
NASA Astrophysics Data System (ADS)
Venet, M.; Pinard, H.; McIntyre, J.; Berthoz, A.; Lacquaniti, F.
The goal of the Kinelite Project is to develop a space qualified motion analysis system to be used in space by the scientific community, mainly to support neuroscience protocols. The measurement principle of the Kinelite is to determine, by triangulation mean, the 3D position of small, lightweight, reflective markers positionned at the different points of interest. The scene is illuminated by Infra Red flashes and the reflected light is acquired by up to 8 precalibrated and synchronized CCD cameras. The main characteristics of the system are: - Camera field of view: 45 °, - Number of cameras: 2 to 8, - Acquisition frequency: 25, 50, 100 or 200 Hz, - CCD format: 256 × 256, - Number of markers: up to 64, - 3D accuracy: 2 mm, - Main dimensions: 45 cm × 45 cm × 30 cm, - Mass: 23 kg, - Power consumption: less than 200 W. The Kinelite will first fly aboard the NASA Spacelab; it will be used, during the NEUROLAB mission (4/98), to support the "Frames of References and Internal Models" (Principal Investigator: Pr. A.BERTHOZ, Co Investigators: J. Mc INTYRE, F. LACQUANITI).
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.
Test Rover at JPL During Preparation for Mars Rover Low-Angle Selfie
2015-08-19
This view of a test rover at NASA's Jet Propulsion Laboratory, Pasadena, California, results from advance testing of arm positions and camera pointings for taking a low-angle self-portrait of NASA's Curiosity Mars rover. This rehearsal in California led to a dramatic Aug. 5, 2015, selfie of Curiosity, online at PIA19807. Curiosity's arm-mounted Mars Hand Lens Imager (MAHLI) camera took 92 of component images that were assembled into that mosaic. The rover team positioned the camera lower in relation to the rover body than for any previous full self-portrait of Curiosity. This practice version was taken at JPL's Mars Yard in July 2013, using the Vehicle System Test Bed (VSTB) rover, which has a test copy of MAHLI on its robotic arm. MAHLI was built by Malin Space Science Systems, San Diego. JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover. http://photojournal.jpl.nasa.gov/catalog/PIA19810
NASA Technical Reports Server (NTRS)
1994-01-01
In laparoscopic surgery, tiny incisions are made in the patient's body and a laparoscope (an optical tube with a camera at the end) is inserted. The camera's image is projected onto two video screens, whose views guide the surgeon through the procedure. AESOP, a medical robot developed by Computer Motion, Inc. with NASA assistance, eliminates the need for a human assistant to operate the camera. The surgeon uses a foot pedal control to move the device, allowing him to use both hands during the surgery. Miscommunication is avoided; AESOP's movement is smooth and steady, and the memory vision is invaluable. Operations can be completed more quickly, and the patient spends less time under anesthesia. AESOP has been approved by the FDA.
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 Astrophysics Data System (ADS)
Hatala, J.; Sonnentag, O.; Detto, M.; Runkle, B.; Vargas, R.; Kelly, M.; Baldocchi, D. D.
2009-12-01
Ground-based, visible light imagery has been used for different purposes in agricultural and ecological research. A series of recent studies explored the utilization of networked digital cameras to continuously monitor vegetation by taking oblique canopy images at fixed view angles and time intervals. In our contribution we combine high temporal resolution digital camera imagery, eddy-covariance, and meteorological measurements with weekly field-based hyperspectral and LAI measurements to gain new insights on temporal changes in canopy structure and functioning of two managed ecosystems in California’s Sacramento-San Joaquin River Delta: a pasture infested by the invasive perennial pepperweed (Lepidium latifolium) and a rice plantation (Oryza sativa). Specific questions we address are: a) how does year-round grazing affect pepperweed canopy development, b) is it possible to identify phenological key events of managed ecosystems (pepperweed: flowering; rice: heading) from the limited spectral information of digital camera imagery, c) is a simple greenness index derived from digital camera imagery sufficient to track leaf area index and canopy development of managed ecosystems, and d) what are the scales of temporal correlation between digital camera signals and carbon and water fluxes of managed ecosystems? Preliminary results for the pasture-pepperweed ecosystem show that year-round grazing inhibits the accumulation of dead stalks causing earlier green-up and that digital camera imagery is well suited to capture the onset of flowering and the associated decrease in photosynthetic CO2 uptake. Results from our analyses are of great relevance from both a global environmental change and land management perspective.
Hand-eye calibration using a target registration error model.
Chen, Elvis C S; Morgan, Isabella; Jayarathne, Uditha; Ma, Burton; Peters, Terry M
2017-10-01
Surgical cameras are prevalent in modern operating theatres and are often used as a surrogate for direct vision. Visualisation techniques (e.g. image fusion) made possible by tracking the camera require accurate hand-eye calibration between the camera and the tracking system. The authors introduce the concept of 'guided hand-eye calibration', where calibration measurements are facilitated by a target registration error (TRE) model. They formulate hand-eye calibration as a registration problem between homologous point-line pairs. For each measurement, the position of a monochromatic ball-tip stylus (a point) and its projection onto the image (a line) is recorded, and the TRE of the resulting calibration is predicted using a TRE model. The TRE model is then used to guide the placement of the calibration tool, so that the subsequent measurement minimises the predicted TRE. Assessing TRE after each measurement produces accurate calibration using a minimal number of measurements. As a proof of principle, they evaluated guided calibration using a webcam and an endoscopic camera. Their endoscopic camera results suggest that millimetre TRE is achievable when at least 15 measurements are acquired with the tracker sensor ∼80 cm away on the laparoscope handle for a target ∼20 cm away from the camera.
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.
Projective Structure from Two Uncalibrated Images: Structure from Motion and Recognition
1992-09-01
correspondence between points in Maybank 1990). The question, therefore, is why look for both views more of a problem, and hence, may make the...plane is fixed with respect to the 1987, Faugeras, Luong and Maybank 1992). The prob- camera coordinate frame. A rigid camera motion, there- lem of...the second reference Rieger-Lawton 1985, Faugeras and Maybank 1990, Hil- plane (assuming the four object points Pi, j = 1, ...,4, dreth 1991, Faugeras
D Animation Reconstruction from Multi-Camera Coordinates Transformation
NASA Astrophysics Data System (ADS)
Jhan, J. P.; Rau, J. Y.; Chou, C. M.
2016-06-01
Reservoir dredging issues are important to extend the life of reservoir. The most effective and cost reduction way is to construct a tunnel to desilt the bottom sediment. Conventional technique is to construct a cofferdam to separate the water, construct the intake of tunnel inside and remove the cofferdam afterwards. In Taiwan, the ZengWen reservoir dredging project will install an Elephant-trunk Steel Pipe (ETSP) in the water to connect the desilting tunnel without building the cofferdam. Since the installation is critical to the whole project, a 1:20 model was built to simulate the installation steps in a towing tank, i.e. launching, dragging, water injection, and sinking. To increase the construction safety, photogrammetry technic is adopted to record images during the simulation, compute its transformation parameters for dynamic analysis and reconstruct the 4D animations. In this study, several Australiscoded targets are fixed on the surface of ETSP for auto-recognition and measurement. The cameras orientations are computed by space resection where the 3D coordinates of coded targets are measured. Two approaches for motion parameters computation are proposed, i.e. performing 3D conformal transformation from the coordinates of cameras and relative orientation computation by the orientation of single camera. Experimental results show the 3D conformal transformation can achieve sub-mm simulation results, and relative orientation computation shows the flexibility for dynamic motion analysis which is easier and more efficiency.
A 3D camera for improved facial recognition
NASA Astrophysics Data System (ADS)
Lewin, Andrew; Orchard, David A.; Scott, Andrew M.; Walton, Nicholas A.; Austin, Jim
2004-12-01
We describe a camera capable of recording 3D images of objects. It does this by projecting thousands of spots onto an object and then measuring the range to each spot by determining the parallax from a single frame. A second frame can be captured to record a conventional image, which can then be projected onto the surface mesh to form a rendered skin. The camera is able of locating the images of the spots to a precision of better than one tenth of a pixel, and from this it can determine range to an accuracy of less than 1 mm at 1 meter. The data can be recorded as a set of two images, and is reconstructed by forming a 'wire mesh' of range points and morphing the 2 D image over this structure. The camera can be used to record the images of faces and reconstruct the shape of the face, which allows viewing of the face from various angles. This allows images to be more critically inspected for the purpose of identifying individuals. Multiple images can be stitched together to create full panoramic images of head sized objects that can be viewed from any direction. The system is being tested with a graph matching system capable of fast and accurate shape comparisons for facial recognition. It can also be used with "models" of heads and faces to provide a means of obtaining biometric data.
Astronaut Walz on flight deck with IMAX camera
1996-11-04
STS079-362-023 (16-26 Sept. 1996) --- Astronaut Carl E. Walz, mission specialist, positions the IMAX camera for a shoot on the flight deck of the Space Shuttle Atlantis. The IMAX project is a collaboration among NASA, the Smithsonian Institution's National Air and Space Museum, IMAX Systems Corporation and the Lockheed Corporation to document in motion picture format significant space activities and promote NASA's educational goals using the IMAX film medium. This system, developed by IMAX of Toronto, uses specially designed 65mm cameras and projectors to record and display very high definition color motion pictures which, accompanied by six-channel high fidelity sound, are displayed on screens in IMAX and OMNIMAX theaters that are up to ten times larger than a conventional screen, producing a feeling of "being there." The 65mm photography is transferred to 70mm motion picture films for showing in IMAX theaters. IMAX cameras have been flown on 14 previous missions.
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.
NASA Technical Reports Server (NTRS)
Almeida, Eduardo DeBrito
2012-01-01
This report discusses work completed over the summer at the Jet Propulsion Laboratory (JPL), California Institute of Technology. A system is presented to guide ground or aerial unmanned robots using computer vision. The system performs accurate camera calibration, camera pose refinement and surface extraction from images collected by a camera mounted on the vehicle. The application motivating the research is planetary exploration and the vehicles are typically rovers or unmanned aerial vehicles. The information extracted from imagery is used primarily for navigation, as robot location is the same as the camera location and the surfaces represent the terrain that rovers traverse. The processed information must be very accurate and acquired very fast in order to be useful in practice. The main challenge being addressed by this project is to achieve high estimation accuracy and high computation speed simultaneously, a difficult task due to many technical reasons.
To catch a comet: Technical overview of CAN DO G-324
NASA Technical Reports Server (NTRS)
Obrien, T. J. (Editor)
1986-01-01
The primary objective of the C. E. Williams Middle School Get Away Special CAN DO is the photographing of Comet Halley. The project will involve middle school students, grades 6 through 8, in the study and interpretation of astronomical photographs and techniques. G-324 is contained in a 5 cubic foot GAS Canister with an opening door and pyrex window for photography. It will be pressurized with one atmosphere of dry nitrogen. Three 35mm still cameras with 250 exposure film backs and different focal length lenses will be fired by a combination of automatic timer and an active comet detector. A lightweight 35mm movie camera will shoot single exposures at about 1/2 minute intervals to give an overlapping skymap of the mission. The fifth camera is a solid state television camera specially constructed for detection of the comet by microprocessor.
2017-10-16
Inside the Spectrum prototype unit, organisms in a Petri plate are exposed to blue excitation lighting. The device works by exposing organisms to different colors of fluorescent light while a camera records what's happening with time-lapse photography. Results from the Spectrum project will shed light on which living things are best suited for long-duration flights into deep space.
Audiovisual Physics Reports: Students' Video Production as a Strategy for the Didactic Laboratory
ERIC Educational Resources Information Center
Pereira, Marcus Vinicius; de Souza Barros, Susana; de Rezende Filho, Luiz Augusto C.; de A. Fauth, Leduc Hermeto
2012-01-01
Constant technological advancement has facilitated access to digital cameras and cell phones. Involving students in a video production project can work as a motivating aspect to make them active and reflective in their learning, intellectually engaged in a recursive process. This project was implemented in high school level physics laboratory…
2017-10-16
Inside the Spectrum prototype unit, organisms in a Petri plate are exposed to different colors of lighting. The device works by exposing organisms to different colors of fluorescent light while a camera records what's happening with time-lapse photography. Results from the Spectrum project will shed light on which living things are best suited for long-duration flights into deep space.
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.
Uncooled Terahertz real-time imaging 2D arrays developed at LETI: present status and perspectives
NASA Astrophysics Data System (ADS)
Simoens, François; Meilhan, Jérôme; Dussopt, Laurent; Nicolas, Jean-Alain; Monnier, Nicolas; Sicard, Gilles; Siligaris, Alexandre; Hiberty, Bruno
2017-05-01
As for other imaging sensor markets, whatever is the technology, the commercial spread of terahertz (THz) cameras has to fulfil simultaneously the criteria of high sensitivity and low cost and SWAP (size, weight and power). Monolithic silicon-based 2D sensors integrated in uncooled THz real-time cameras are good candidates to meet these requirements. Over the past decade, LETI has been studying and developing such arrays with two complimentary technological approaches, i.e. antenna-coupled silicon bolometers and CMOS Field Effect Transistors (FET), both being compatible to standard silicon microelectronics processes. LETI has leveraged its know-how in thermal infrared bolometer sensors in developing a proprietary architecture for THz sensing. High technological maturity has been achieved as illustrated by the demonstration of fast scanning of large field of view and the recent birth of a commercial camera. In the FET-based THz field, recent works have been focused on innovative CMOS read-out-integrated circuit designs. The studied architectures take advantage of the large pixel pitch to enhance the flexibility and the sensitivity: an embedded in-pixel configurable signal processing chain dramatically reduces the noise. Video sequences at 100 frames per second using our 31x31 pixels 2D Focal Plane Arrays (FPA) have been achieved. The authors describe the present status of these developments and perspectives of performance evolutions are discussed. Several experimental imaging tests are also presented in order to illustrate the capabilities of these arrays to address industrial applications such as non-destructive testing (NDT), security or quality control of food.
NASA Astrophysics Data System (ADS)
Rizzo, G.; Batignani, G.; Benkechkache, M. A.; Bettarini, S.; Casarosa, G.; Comotti, D.; Dalla Betta, G.-F.; Fabris, L.; Forti, F.; Grassi, M.; Lodola, L.; Malcovati, P.; Manghisoni, M.; Mendicino, R.; Morsani, F.; Paladino, A.; Pancheri, L.; Paoloni, E.; Ratti, L.; Re, V.; Traversi, G.; Vacchi, C.; Verzellesi, G.; Xu, H.
2016-07-01
The INFN PixFEL project is developing the fundamental building blocks for a large area X-ray imaging camera to be deployed at next generation free electron laser (FEL) facilities with unprecedented intensity. Improvement in performance beyond the state of art in imaging instrumentation will be explored adopting advanced technologies like active edge sensors, a 65 nm node CMOS process and vertical integration. These are the key ingredients of the PixFEL project to realize a seamless large area focal plane instrument composed by a matrix of multilayer four-side buttable tiles. In order to minimize the dead area and reduce ambiguities in image reconstruction, a fine pitch active edge thick sensor is being optimized to cope with very high intensity photon flux, up to 104 photons per pixel, in the range from 1 to 10 keV. A low noise analog front-end channel with this wide dynamic range and a novel dynamic compression feature, together with a low power 10 bit analog to digital conversion up to 5 MHz, has been realized in a 110 μm pitch with a 65 nm CMOS process. Vertical interconnection of two CMOS tiers will be also explored in the future to build a four-side buttable readout chip with high density memories. In the long run the objective of the PixFEL project is to build a flexible X-ray imaging camera for operation both in burst mode, like at the European X-FEL, or in continuous mode with the high frame rates anticipated for future FEL facilities.
Park, Jae Byung; Lee, Seung Hun; Lee, Il Jae
2009-01-01
In this study, we propose a precise 3D lug pose detection sensor for automatic robot welding of a lug to a huge steel plate used in shipbuilding, where the lug is a handle to carry the huge steel plate. The proposed sensor consists of a camera and four laser line diodes, and its design parameters are determined by analyzing its detectable range and resolution. For the lug pose acquisition, four laser lines are projected on both lug and plate, and the projected lines are detected by the camera. For robust detection of the projected lines against the illumination change, the vertical threshold, thinning, Hough transform and separated Hough transform algorithms are successively applied to the camera image. The lug pose acquisition is carried out by two stages: the top view alignment and the side view alignment. The top view alignment is to detect the coarse lug pose relatively far from the lug, and the side view alignment is to detect the fine lug pose close to the lug. After the top view alignment, the robot is controlled to move close to the side of the lug for the side view alignment. By this way, the precise 3D lug pose can be obtained. Finally, experiments with the sensor prototype are carried out to verify the feasibility and effectiveness of the proposed sensor. PMID:22400007
Tomographic Small-Animal Imaging Using a High-Resolution Semiconductor Camera
Kastis, GA; Wu, MC; Balzer, SJ; Wilson, DW; Furenlid, LR; Stevenson, G; Barber, HB; Barrett, HH; Woolfenden, JM; Kelly, P; Appleby, M
2015-01-01
We have developed a high-resolution, compact semiconductor camera for nuclear medicine applications. The modular unit has been used to obtain tomographic images of phantoms and mice. The system consists of a 64 x 64 CdZnTe detector array and a parallel-hole tungsten collimator mounted inside a 17 cm x 5.3 cm x 3.7 cm tungsten-aluminum housing. The detector is a 2.5 cm x 2.5 cm x 0.15 cm slab of CdZnTe connected to a 64 x 64 multiplexer readout via indium-bump bonding. The collimator is 7 mm thick, with a 0.38 mm pitch that matches the detector pixel pitch. We obtained a series of projections by rotating the object in front of the camera. The axis of rotation was vertical and about 1.5 cm away from the collimator face. Mouse holders were made out of acrylic plastic tubing to facilitate rotation and the administration of gas anesthetic. Acquisition times were varied from 60 sec to 90 sec per image for a total of 60 projections at an equal spacing of 6 degrees between projections. We present tomographic images of a line phantom and mouse bone scan and assess the properties of the system. The reconstructed images demonstrate spatial resolution on the order of 1–2 mm. PMID:26568676
Junocam: Juno's Outreach Camera
NASA Astrophysics Data System (ADS)
Hansen, C. J.; Caplinger, M. A.; Ingersoll, A.; Ravine, M. A.; Jensen, E.; Bolton, S.; Orton, G.
2017-11-01
Junocam is a wide-angle camera designed to capture the unique polar perspective of Jupiter offered by Juno's polar orbit. Junocam's four-color images include the best spatial resolution ever acquired of Jupiter's cloudtops. Junocam will look for convective clouds and lightning in thunderstorms and derive the heights of the clouds. Junocam will support Juno's radiometer experiment by identifying any unusual atmospheric conditions such as hotspots. Junocam is on the spacecraft explicitly to reach out to the public and share the excitement of space exploration. The public is an essential part of our virtual team: amateur astronomers will supply ground-based images for use in planning, the public will weigh in on which images to acquire, and the amateur image processing community will help process the data.
Filtered back-projection algorithm for Compton telescopes
Gunter, Donald L [Lisle, IL
2008-03-18
A method for the conversion of Compton camera data into a 2D image of the incident-radiation flux on the celestial sphere includes detecting coincident gamma radiation flux arriving from various directions of a 2-sphere. These events are mapped by back-projection onto the 2-sphere to produce a convolution integral that is subsequently stereographically projected onto a 2-plane to produce a second convolution integral which is deconvolved by the Fourier method to produce an image that is then projected onto the 2-sphere.
NASA Technical Reports Server (NTRS)
Holub, R.; Shenk, W. E.
1973-01-01
Four registered channels (0.2 to 4, 6.5 to 7, 10 to 11, and 20 to 23 microns) of the Nimbus 3 Medium Resolution Infrared Radiometer (MRIR) were used to study 24-hr changes in the structure of an extratropical cyclone during a 6-day period in May 1969. Use of a stereographic-horizon map projection insured that the storm was mapped with a single perspective throughout the series and allowed the convenient preparation of 24-hr difference maps of the infrared radiation fields. Single-channel and multispectral analysis techniques were employed to establish the positions and vertical slopes of jetstreams, large cloud systems, and major features of middle and upper tropospheric circulation. Use of these techniques plus the difference maps and continuity of observation allowed the early detection of secondary cyclones developing within the circulation of the primary cyclone. An automated, multispectral cloud-type identification technique was developed, and comparisons that were made with conventional ship reports and with high-resolution visual data from the image dissector camera system showed good agreement.
Results from an 8 Joule RMF-FRC Plasma Translation Experiment for Space Propulsion
NASA Astrophysics Data System (ADS)
Hill, Carrie; Uchizono, Nolan; Holmes, Michael
2017-10-01
Field-Reversed Configuration (FRC) thrusters are attractive for advanced in-space propulsion technology as their projected performance, low specific mass, and propellant flexibility offer significant benefits over state-of-the art thrusters. A benchtop experiment to evaluate FRC thruster behavior using a Rotating Magnetic Field (RMF) formation method was constructed at the Air Force Research Laboratory. This experiment generated an RMF-FRC in a conical geometry and accelerated the plasma into a field-free drift region, using 8 J of input energy. Downstream plasma probes in a time-of-flight array measured the exhaust contents of the plasma plume. Results from this diagnostic demonstrated that the ejected mass and ion exit velocities fell short of the desired specific impulse and momentum. Two high-speed cameras were installed to diagnose the gross plasma behavior from two perspectives. Results from these images are presented here. These images show that the plasma generated in the formation region for several different operating conditions was highly non-uniform and did not form a stable closed-field topology that is expected from RMF-FRC plasmas.
Global vision system in laparoscopy.
Rivas-Blanco, I; Sánchez-de-Badajoz, E; García-Morales, I; Lage-Sánchez, J M; Sánchez-Gallegos, P; Pérez-Del-Pulgar, C J; Muñoz, V F
2017-05-01
The main difficulty in laparoscopic or robot-assisted surgery is the narrow visual field, restricted by the endoscope's access port. This restriction is coupled with the difficulty of handling the instruments, which is due not only to the access port but also to the loss of depth of field and perspective due to the lack of natural lighting. In this article, we describe a global vision system and report on our initial experience in a porcine model. The global vision system consists of a series of intraabdominal devices, which increase the visual field and help recover perspective through the simulation of natural shadows. These devices are a series of high-definition cameras and LED lights, which are inserted and fixed to the wall using magnets. The system's efficacy was assessed in a varicocelectomy and nephrectomy. The various intraabdominal cameras offer a greater number of intuitive points of view of the surgical field compared with the conventional telescope and appear to provide a similar view as that in open surgery. Areas previously inaccessible to the standard telescope can now be reached. The additional light sources create shadows that increase the perspective of the surgical field. This system appears to increase the possibilities for laparoscopic or robot-assisted surgery because it offers an instant view of almost the entire abdomen, enabling more complex procedures, which currently require an open pathway. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.
GoPro as an Ethnographic Tool: A Wayfinding Study in an Academic Library
ERIC Educational Resources Information Center
Kinsley, Kirsten M.; Schoonover, Dan; Spitler, Jasmine
2016-01-01
In this study, researchers sought to capture students' authentic experience of finding books in the main library using a GoPro camera and the think-aloud protocol. The GoPro provided a first-person perspective and was an effective ethnographic tool for observing a student's individual experience, while also demonstrating what tools they use to…
Seabird acoustic communication at sea: a new perspective using bio-logging devices.
Thiebault, Andréa; Pistorius, Pierre; Mullers, Ralf; Tremblay, Yann
2016-08-05
Most seabirds are very noisy at their breeding colonies, when aggregated in high densities. Calls are used for individual recognition and also emitted during agonistic interactions. When at sea, many seabirds aggregate over patchily distributed resources and may benefit from foraging in groups. Because these aggregations are so common, it raises the question of whether seabirds use acoustic communication when foraging at sea? We deployed video-cameras with built in microphones on 36 Cape gannets (Morus capensis) during the breeding season of 2010-2011 at Bird Island (Algoa Bay, South Africa) to study their foraging behaviour and vocal activity at sea. Group formation was derived from the camera footage. During ~42 h, calls were recorded on 72 occasions from 16 birds. Vocalization exclusively took place in the presence of conspecifics, and mostly in feeding aggregations (81% of the vocalizations). From the observation of the behaviours of birds associated with the emission of calls, we suggest that the calls were emitted to avoid collisions between birds. Our observations show that at least some seabirds use acoustic communication when foraging at sea. These findings open up new perspectives for research on seabirds foraging ecology and their interactions at sea.
Seabird acoustic communication at sea: a new perspective using bio-logging devices
Thiebault, Andréa; Pistorius, Pierre; Mullers, Ralf; Tremblay, Yann
2016-01-01
Most seabirds are very noisy at their breeding colonies, when aggregated in high densities. Calls are used for individual recognition and also emitted during agonistic interactions. When at sea, many seabirds aggregate over patchily distributed resources and may benefit from foraging in groups. Because these aggregations are so common, it raises the question of whether seabirds use acoustic communication when foraging at sea? We deployed video-cameras with built in microphones on 36 Cape gannets (Morus capensis) during the breeding season of 2010–2011 at Bird Island (Algoa Bay, South Africa) to study their foraging behaviour and vocal activity at sea. Group formation was derived from the camera footage. During ~42 h, calls were recorded on 72 occasions from 16 birds. Vocalization exclusively took place in the presence of conspecifics, and mostly in feeding aggregations (81% of the vocalizations). From the observation of the behaviours of birds associated with the emission of calls, we suggest that the calls were emitted to avoid collisions between birds. Our observations show that at least some seabirds use acoustic communication when foraging at sea. These findings open up new perspectives for research on seabirds foraging ecology and their interactions at sea. PMID:27492779
Registration of multiple video images to preoperative CT for image-guided surgery
NASA Astrophysics Data System (ADS)
Clarkson, Matthew J.; Rueckert, Daniel; Hill, Derek L.; Hawkes, David J.
1999-05-01
In this paper we propose a method which uses multiple video images to establish the pose of a CT volume with respect to video camera coordinates for use in image guided surgery. The majority of neurosurgical procedures require the neurosurgeon to relate the pre-operative MR/CT data to the intra-operative scene. Registration of 2D video images to the pre-operative 3D image enables a perspective projection of the pre-operative data to be overlaid onto the video image. Our registration method is based on image intensity and uses a simple iterative optimization scheme to maximize the mutual information between a video image and a rendering from the pre-operative data. Video images are obtained from a stereo operating microscope, with a field of view of approximately 110 X 80 mm. We have extended an existing information theoretical framework for 2D-3D registration, so that multiple video images can be registered simultaneously to the pre-operative data. Experiments were performed on video and CT images of a skull phantom. We took three video images, and our algorithm registered these individually to the 3D image. The mean projection error varied between 4.33 and 9.81 millimeters (mm), and the mean 3D error varied between 4.47 and 11.92 mm. Using our novel techniques we then registered five video views simultaneously to the 3D model. This produced an accurate and robust registration with a mean projection error of 0.68 mm and a mean 3D error of 1.05 mm.
Calibration of an Outdoor Distributed Camera Network with a 3D Point Cloud
Ortega, Agustín; Silva, Manuel; Teniente, Ernesto H.; Ferreira, Ricardo; Bernardino, Alexandre; Gaspar, José; Andrade-Cetto, Juan
2014-01-01
Outdoor camera networks are becoming ubiquitous in critical urban areas of the largest cities around the world. Although current applications of camera networks are mostly tailored to video surveillance, recent research projects are exploiting their use to aid robotic systems in people-assisting tasks. Such systems require precise calibration of the internal and external parameters of the distributed camera network. Despite the fact that camera calibration has been an extensively studied topic, the development of practical methods for user-assisted calibration that minimize user intervention time and maximize precision still pose significant challenges. These camera systems have non-overlapping fields of view, are subject to environmental stress, and are likely to suffer frequent recalibration. In this paper, we propose the use of a 3D map covering the area to support the calibration process and develop an automated method that allows quick and precise calibration of a large camera network. We present two cases of study of the proposed calibration method: one is the calibration of the Barcelona Robot Lab camera network, which also includes direct mappings (homographies) between image coordinates and world points in the ground plane (walking areas) to support person and robot detection and localization algorithms. The second case consist of improving the GPS positioning of geo-tagged images taken with a mobile device in the Facultat de Matemàtiques i Estadística (FME) patio at the Universitat Politècnica de Catalunya (UPC). PMID:25076221
Calibration of an outdoor distributed camera network with a 3D point cloud.
Ortega, Agustín; Silva, Manuel; Teniente, Ernesto H; Ferreira, Ricardo; Bernardino, Alexandre; Gaspar, José; Andrade-Cetto, Juan
2014-07-29
Outdoor camera networks are becoming ubiquitous in critical urban areas of the largest cities around the world. Although current applications of camera networks are mostly tailored to video surveillance, recent research projects are exploiting their use to aid robotic systems in people-assisting tasks. Such systems require precise calibration of the internal and external parameters of the distributed camera network. Despite the fact that camera calibration has been an extensively studied topic, the development of practical methods for user-assisted calibration that minimize user intervention time and maximize precision still pose significant challenges. These camera systems have non-overlapping fields of view, are subject to environmental stress, and are likely to suffer frequent recalibration. In this paper, we propose the use of a 3D map covering the area to support the calibration process and develop an automated method that allows quick and precise calibration of a large camera network. We present two cases of study of the proposed calibration method: one is the calibration of the Barcelona Robot Lab camera network, which also includes direct mappings (homographies) between image coordinates and world points in the ground plane (walking areas) to support person and robot detection and localization algorithms. The second case consist of improving the GPS positioning of geo-tagged images taken with a mobile device in the Facultat de Matemàtiques i Estadística (FME) patio at the Universitat Politècnica de Catalunya (UPC).
Perspective: “The Financial Impact of Alternative Water Project Delivery Models” in the Water Sector
The Water Finance Center developed this companion perspective document to a UNC EFC report on Alternative Water Project Delivery Models to broaden understanding of this alternative procurement method.
Accuracy Analysis for Automatic Orientation of a Tumbling Oblique Viewing Sensor System
NASA Astrophysics Data System (ADS)
Stebner, K.; Wieden, A.
2014-03-01
Dynamic camera systems with moving parts are difficult to handle in photogrammetric workflow, because it is not ensured that the dynamics are constant over the recording period. Minimum changes of the camera's orientation greatly influence the projection of oblique images. In this publication these effects - originating from the kinematic chain of a dynamic camera system - are analysed and validated. A member of the Modular Airborne Camera System family - MACS-TumbleCam - consisting of a vertical viewing and a tumbling oblique camera was used for this investigation. Focus is on dynamic geometric modeling and the stability of the kinematic chain. To validate the experimental findings, the determined parameters are applied to the exterior orientation of an actual aerial image acquisition campaign using MACS-TumbleCam. The quality of the parameters is sufficient for direct georeferencing of oblique image data from the orientation information of a synchronously captured vertical image dataset. Relative accuracy for the oblique data set ranges from 1.5 pixels when using all images of the image block to 0.3 pixels when using only adjacent images.
NASA Astrophysics Data System (ADS)
Keane, Tommy P.; Saber, Eli; Rhody, Harvey; Savakis, Andreas; Raj, Jeffrey
2012-04-01
Contemporary research in automated panorama creation utilizes camera calibration or extensive knowledge of camera locations and relations to each other to achieve successful results. Research in image registration attempts to restrict these same camera parameters or apply complex point-matching schemes to overcome the complications found in real-world scenarios. This paper presents a novel automated panorama creation algorithm by developing an affine transformation search based on maximized mutual information (MMI) for region-based registration. Standard MMI techniques have been limited to applications with airborne/satellite imagery or medical images. We show that a novel MMI algorithm can approximate an accurate registration between views of realistic scenes of varying depth distortion. The proposed algorithm has been developed using stationary, color, surveillance video data for a scenario with no a priori camera-to-camera parameters. This algorithm is robust for strict- and nearly-affine-related scenes, while providing a useful approximation for the overlap regions in scenes related by a projective homography or a more complex transformation, allowing for a set of efficient and accurate initial conditions for pixel-based registration.
Motionless active depth from defocus system using smart optics for camera autofocus applications
NASA Astrophysics Data System (ADS)
Amin, M. Junaid; Riza, Nabeel A.
2016-04-01
This paper describes a motionless active Depth from Defocus (DFD) system design suited for long working range camera autofocus applications. The design consists of an active illumination module that projects a scene illuminating coherent conditioned optical radiation pattern which maintains its sharpness over multiple axial distances allowing an increased DFD working distance range. The imager module of the system responsible for the actual DFD operation deploys an electronically controlled variable focus lens (ECVFL) as a smart optic to enable a motionless imager design capable of effective DFD operation. An experimental demonstration is conducted in the laboratory which compares the effectiveness of the coherent conditioned radiation module versus a conventional incoherent active light source, and demonstrates the applicability of the presented motionless DFD imager design. The fast response and no-moving-parts features of the DFD imager design are especially suited for camera scenarios where mechanical motion of lenses to achieve autofocus action is challenging, for example, in the tiny camera housings in smartphones and tablets. Applications for the proposed system include autofocus in modern day digital cameras.
Bird's-Eye View of Opportunity at 'Erebus' (Polar)
NASA Technical Reports Server (NTRS)
2006-01-01
This view combines frames taken by the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity on the rover's 652nd through 663rd Martian days, or sols (Nov. 23 to Dec. 5, 2005), at the edge of 'Erebus Crater.' The mosaic is presented as a polar projection. This type of projection provides a kind of overhead view of all of the surrounding terrain. Opportunity examined targets on the outcrop called 'Rimrock' in front of the rover, testing the mobility and operation of Opportunity's robotic arm. The view shows examples of the dunes and ripples that Opportunity has been crossing as the rover drives on the Meridiani plains. This view is an approximate true color rendering composed of images taken through the camera's 750-nanometer, 530-nanometer and 430-nanometer filters.Interactive projection for aerial dance using depth sensing camera
NASA Astrophysics Data System (ADS)
Dubnov, Tammuz; Seldess, Zachary; Dubnov, Shlomo
2014-02-01
This paper describes an interactive performance system for oor and Aerial Dance that controls visual and sonic aspects of the presentation via a depth sensing camera (MS Kinect). In order to detect, measure and track free movement in space, 3 degree of freedom (3-DOF) tracking in space (on the ground and in the air) is performed using IR markers. Gesture tracking and recognition is performed using a simpli ed HMM model that allows robust mapping of the actor's actions to graphics and sound. Additional visual e ects are achieved by segmentation of the actor body based on depth information, allowing projection of separate imagery on the performer and the backdrop. Artistic use of augmented reality performance relative to more traditional concepts of stage design and dramaturgy are discussed.
Soft x-ray reduction camera for submicron lithography
Hawryluk, Andrew M.; Seppala, Lynn G.
1991-01-01
Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm.sup.2. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics.
Analytically based photon scatter modeling for a multipinhole cardiac SPECT camera.
Pourmoghaddas, Amir; Wells, R Glenn
2016-11-01
Dedicated cardiac SPECT scanners have improved performance over standard gamma cameras allowing reductions in acquisition times and/or injected activity. One approach to improving performance has been to use pinhole collimators, but this can cause position-dependent variations in attenuation, sensitivity, and spatial resolution. CT attenuation correction (AC) and an accurate system model can compensate for many of these effects; however, scatter correction (SC) remains an outstanding issue. In addition, in cameras using cadmium-zinc-telluride-based detectors, a large portion of unscattered photons is detected with reduced energy (low-energy tail). Consequently, application of energy-based SC approaches in these cameras leads to a higher increase in noise than with standard cameras due to the subtraction of true counts detected in the low-energy tail. Model-based approaches with parallel-hole collimator systems accurately calculate scatter based on the physics of photon interactions in the patient and camera and generate lower-noise estimates of scatter than energy-based SC. In this study, the accuracy of a model-based SC method was assessed using physical phantom studies on the GE-Discovery NM530c and its performance was compared to a dual energy window (DEW)-SC method. The analytical photon distribution (APD) method was used to calculate the distribution of probabilities that emitted photons will scatter in the surrounding scattering medium and be subsequently detected. APD scatter calculations for 99m Tc-SPECT (140 ± 14 keV) were validated with point-source measurements and 15 anthropomorphic cardiac-torso phantom experiments and varying levels of extra-cardiac activity causing scatter inside the heart. The activity inserted into the myocardial compartment of the phantom was first measured using a dose calibrator. CT images were acquired on an Infinia Hawkeye (GE Healthcare) SPECT/CT and coregistered with emission data for AC. For comparison, DEW scatter projections (120 ± 6 keV ) were also extracted from the acquired list-mode SPECT data. Either APD or DEW scatter projections were subtracted from corresponding 140 keV measured projections and then reconstructed with AC (APD-SC and DEW-SC). Quantitative accuracy of the activity measured in the heart for the APD-SC and DEW-SC images was assessed against dose calibrator measurements. The difference between modeled and acquired projections was measured as the root-mean-squared-error (RMSE). APD-modeled projections for a clinical cardiac study were also evaluated. APD-modeled projections showed good agreement with SPECT measurements and had reduced noise compared to DEW scatter estimates. APD-SC reduced mean error in activity measurement compared to DEW-SC in images and the reduction was statistically significant where the scatter fraction (SF) was large (mean SF = 28.5%, T-test p = 0.007). APD-SC reduced measurement uncertainties as well; however, the difference was not found to be statistically significant (F-test p > 0.5). RMSE comparisons showed that elevated levels of scatter did not significantly contribute to a change in RMSE (p > 0.2). Model-based APD scatter estimation is feasible for dedicated cardiac SPECT scanners with pinhole collimators. APD-SC images performed better than DEW-SC images and improved the accuracy of activity measurement in high-scatter scenarios.
ERIC Educational Resources Information Center
Koole, Marguerite
2018-01-01
This article is primarily a theoretical piece that uses a model of mobile learning, the FRAME model (Koole 2009), to explore a mobile teacher-training project that took place in Papua New Guinea: the SMS Story. The author takes a sociomaterial perspective, drawing upon Barad's agential realism and Sørensen's multiplicity perspective. As the author…
World's fastest and most sensitive astronomical camera
NASA Astrophysics Data System (ADS)
2009-06-01
The next generation of instruments for ground-based telescopes took a leap forward with the development of a new ultra-fast camera that can take 1500 finely exposed images per second even when observing extremely faint objects. The first 240x240 pixel images with the world's fastest high precision faint light camera were obtained through a collaborative effort between ESO and three French laboratories from the French Centre National de la Recherche Scientifique/Institut National des Sciences de l'Univers (CNRS/INSU). Cameras such as this are key components of the next generation of adaptive optics instruments of Europe's ground-based astronomy flagship facility, the ESO Very Large Telescope (VLT). ESO PR Photo 22a/09 The CCD220 detector ESO PR Photo 22b/09 The OCam camera ESO PR Video 22a/09 OCam images "The performance of this breakthrough camera is without an equivalent anywhere in the world. The camera will enable great leaps forward in many areas of the study of the Universe," says Norbert Hubin, head of the Adaptive Optics department at ESO. OCam will be part of the second-generation VLT instrument SPHERE. To be installed in 2011, SPHERE will take images of giant exoplanets orbiting nearby stars. A fast camera such as this is needed as an essential component for the modern adaptive optics instruments used on the largest ground-based telescopes. Telescopes on the ground suffer from the blurring effect induced by atmospheric turbulence. This turbulence causes the stars to twinkle in a way that delights poets, but frustrates astronomers, since it blurs the finest details of the images. Adaptive optics techniques overcome this major drawback, so that ground-based telescopes can produce images that are as sharp as if taken from space. Adaptive optics is based on real-time corrections computed from images obtained by a special camera working at very high speeds. Nowadays, this means many hundreds of times each second. The new generation instruments require these corrections to be done at an even higher rate, more than one thousand times a second, and this is where OCam is essential. "The quality of the adaptive optics correction strongly depends on the speed of the camera and on its sensitivity," says Philippe Feautrier from the LAOG, France, who coordinated the whole project. "But these are a priori contradictory requirements, as in general the faster a camera is, the less sensitive it is." This is why cameras normally used for very high frame-rate movies require extremely powerful illumination, which is of course not an option for astronomical cameras. OCam and its CCD220 detector, developed by the British manufacturer e2v technologies, solve this dilemma, by being not only the fastest available, but also very sensitive, making a significant jump in performance for such cameras. Because of imperfect operation of any physical electronic devices, a CCD camera suffers from so-called readout noise. OCam has a readout noise ten times smaller than the detectors currently used on the VLT, making it much more sensitive and able to take pictures of the faintest of sources. "Thanks to this technology, all the new generation instruments of ESO's Very Large Telescope will be able to produce the best possible images, with an unequalled sharpness," declares Jean-Luc Gach, from the Laboratoire d'Astrophysique de Marseille, France, who led the team that built the camera. "Plans are now underway to develop the adaptive optics detectors required for ESO's planned 42-metre European Extremely Large Telescope, together with our research partners and the industry," says Hubin. Using sensitive detectors developed in the UK, with a control system developed in France, with German and Spanish participation, OCam is truly an outcome of a European collaboration that will be widely used and commercially produced. More information The three French laboratories involved are the Laboratoire d'Astrophysique de Marseille (LAM/INSU/CNRS, Université de Provence; Observatoire Astronomique de Marseille Provence), the Laboratoire d'Astrophysique de Grenoble (LAOG/INSU/CNRS, Université Joseph Fourier; Observatoire des Sciences de l'Univers de Grenoble), and the Observatoire de Haute Provence (OHP/INSU/CNRS; Observatoire Astronomique de Marseille Provence). OCam and the CCD220 are the result of five years work, financed by the European commission, ESO and CNRS-INSU, within the OPTICON project of the 6th Research and Development Framework Programme of the European Union. The development of the CCD220, supervised by ESO, was undertaken by the British company e2v technologies, one of the world leaders in the manufacture of scientific detectors. The corresponding OPTICON activity was led by the Laboratoire d'Astrophysique de Grenoble, France. The OCam camera was built by a team of French engineers from the Laboratoire d'Astrophysique de Marseille, the Laboratoire d'Astrophysique de Grenoble and the Observatoire de Haute Provence. In order to secure the continuation of this successful project a new OPTICON project started in June 2009 as part of the 7th Research and Development Framework Programme of the European Union with the same partners, with the aim of developing a detector and camera with even more powerful functionality for use with an artificial laser star. This development is necessary to ensure the image quality of the future 42-metre European Extremely Large Telescope. ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".
NASA Technical Reports Server (NTRS)
Gradl, Paul
2016-01-01
Paired images were collected using a projected pattern instead of standard painting of the speckle pattern on her abdomen. High Speed cameras were post triggered after movements felt. Data was collected at 120 fps -limited due to 60hz frequency of projector. To ensure that kicks and movement data was real a background test was conducted with no baby movement (to correct for breathing and body motion).
Real Time Eye Tracking and Hand Tracking Using Regular Video Cameras for Human Computer Interaction
2011-01-01
Paperwork Reduction Project (0704-0188) Washington, DC 20503. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) January...understand us. More specifically, the computer should be able to infer what we wish to see, do , and interact with through our movements, gestures, and...in depth freedom. Our system differs from the majority of other systems in that we do not use infrared, stereo-cameras, specially-constructed
Liquid lens: advances in adaptive optics
NASA Astrophysics Data System (ADS)
Casey, Shawn Patrick
2010-12-01
'Liquid lens' technologies promise significant advancements in machine vision and optical communications systems. Adaptations for machine vision, human vision correction, and optical communications are used to exemplify the versatile nature of this technology. Utilization of liquid lens elements allows the cost effective implementation of optical velocity measurement. The project consists of a custom image processor, camera, and interface. The images are passed into customized pattern recognition and optical character recognition algorithms. A single camera would be used for both speed detection and object recognition.
HOT CELL BUILDING, TRA632. CONTEXTUAL VIEW ALONG WALLEYE AVENUE, CAMERA ...
HOT CELL BUILDING, TRA-632. CONTEXTUAL VIEW ALONG WALLEYE AVENUE, CAMERA FACING EASTERLY. HOT CELL BUILDING IS AT CENTER LEFT OF VIEW; THE LOW-BAY PROJECTION WITH LADDER IS THE TEST TRAIN ASSEMBLY FACILITY, ADDED IN 1968. MTR BUILDING IS IN LEFT OF VIEW. HIGH-BAY BUILDING AT RIGHT IS THE ENGINEERING TEST REACTOR BUILDING, TRA-642. INL NEGATIVE NO. HD46-32-1. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
Geometric, Kinematic and Radiometric Aspects of Image-Based Measurements
NASA Technical Reports Server (NTRS)
Liu, Tianshu
2002-01-01
This paper discusses theoretical foundations of quantitative image-based measurements for extracting and reconstructing geometric, kinematic and dynamic properties of observed objects. New results are obtained by using a combination of methods in perspective geometry, differential geometry. radiometry, kinematics and dynamics. Specific topics include perspective projection transformation. perspective developable conical surface, perspective projection under surface constraint, perspective invariants, the point correspondence problem. motion fields of curves and surfaces. and motion equations of image intensity. The methods given in this paper arc useful for determining morphology and motion fields of deformable bodies such as elastic bodies. viscoelastic mediums and fluids.
The History of the CONCAM Project: All Sky Monitors in the Digital Age
NASA Astrophysics Data System (ADS)
Nemiroff, Robert; Shamir, Lior; Pereira, Wellesley
2018-01-01
The CONtinuous CAMera (CONCAM) project, which ran from 2000 to (about) 2008, consisted of real-time, Internet-connected, fisheye cameras located at major astronomical observatories. At its peak, eleven CONCAMs around the globe monitored most of the night sky, most of the time. Initially designed to search for transients and stellar variability, CONCAMs gained initial notoriety as cloud monitors. As such, CONCAMs made -- and its successors continue to make -- ground-based astronomy more efficient. The original, compact, fisheye-observatory-in-a-suitcase design underwent several iterations, starting with CONCAM0 and with the last version dubbed CONCAM3. Although the CONCAM project itself concluded after centralized funding diminished, today more locally-operated, commercially-designed, CONCAM-like devices operate than ever before. It has even been shown that modern smartphones can operate in a CONCAM-like mode. It is speculated that the re-instatement of better global coordination of current wide-angle sky monitors could lead to better variability monitoring of the brightest stars and transients.
NASA Astrophysics Data System (ADS)
Lebedev, M. A.; Stepaniants, D. G.; Komarov, D. V.; Vygolov, O. V.; Vizilter, Yu. V.; Zheltov, S. Yu.
2014-08-01
The paper addresses a promising visualization concept related to combination of sensor and synthetic images in order to enhance situation awareness of a pilot during an aircraft landing. A real-time algorithm for a fusion of a sensor image, acquired by an onboard camera, and a synthetic 3D image of the external view, generated in an onboard computer, is proposed. The pixel correspondence between the sensor and the synthetic images is obtained by an exterior orientation of a "virtual" camera using runway points as a geospatial reference. The runway points are detected by the Projective Hough Transform, which idea is to project the edge map onto a horizontal plane in the object space (the runway plane) and then to calculate intensity projections of edge pixels on different directions of intensity gradient. The performed experiments on simulated images show that on a base glide path the algorithm provides image fusion with pixel accuracy, even in the case of significant navigation errors.
Computing camera heading: A study
NASA Astrophysics Data System (ADS)
Zhang, John Jiaxiang
2000-08-01
An accurate estimate of the motion of a camera is a crucial first step for the 3D reconstruction of sites, objects, and buildings from video. Solutions to the camera heading problem can be readily applied to many areas, such as robotic navigation, surgical operation, video special effects, multimedia, and lately even in internet commerce. From image sequences of a real world scene, the problem is to calculate the directions of the camera translations. The presence of rotations makes this problem very hard. This is because rotations and translations can have similar effects on the images, and are thus hard to tell apart. However, the visual angles between the projection rays of point pairs are unaffected by rotations, and their changes over time contain sufficient information to determine the direction of camera translation. We developed a new formulation of the visual angle disparity approach, first introduced by Tomasi, to the camera heading problem. Our new derivation makes theoretical analysis possible. Most notably, a theorem is obtained that locates all possible singularities of the residual function for the underlying optimization problem. This allows identifying all computation trouble spots beforehand, and to design reliable and accurate computational optimization methods. A bootstrap-jackknife resampling method simultaneously reduces complexity and tolerates outliers well. Experiments with image sequences show accurate results when compared with the true camera motion as measured with mechanical devices.
ERIC Educational Resources Information Center
McMillan, Samuel, Ed.; Quinto, Frances, Ed.
Designed as a teacher's guide to stimulate student interest, creativity, and achievement, this teaching guide includes 132 projects which involve the use of photography as an instructional tool. The volume is divided into subject areas with grade levels ranging from kindergarten through higher education. Most projects are multidisciplinary, and…
Snapshot retinal imaging Mueller matrix polarimeter
NASA Astrophysics Data System (ADS)
Wang, Yifan; Kudenov, Michael; Kashani, Amir; Schwiegerling, Jim; Escuti, Michael
2015-09-01
Early diagnosis of glaucoma, which is a leading cause for visual impairment, is critical for successful treatment. It has been shown that Imaging polarimetry has advantages in early detection of structural changes in the retina. Here, we theoretically and experimentally present a snapshot Mueller Matrix Polarimeter fundus camera, which has the potential to record the polarization-altering characteristics of retina with a single snapshot. It is made by incorporating polarization gratings into a fundus camera design. Complete Mueller Matrix data sets can be obtained by analyzing the polarization fringes projected onto the image plane. In this paper, we describe the experimental implementation of the snapshot retinal imaging Mueller matrix polarimeter (SRIMMP), highlight issues related to calibration, and provide preliminary images acquired from the camera.
Laser-Camera Vision Sensing for Spacecraft Mobile Robot Navigation
NASA Technical Reports Server (NTRS)
Maluf, David A.; Khalil, Ahmad S.; Dorais, Gregory A.; Gawdiak, Yuri
2002-01-01
The advent of spacecraft mobile robots-free-flyng sensor platforms and communications devices intended to accompany astronauts or remotely operate on space missions both inside and outside of a spacecraft-has demanded the development of a simple and effective navigation schema. One such system under exploration involves the use of a laser-camera arrangement to predict relative positioning of the mobile robot. By projecting laser beams from the robot, a 3D reference frame can be introduced. Thus, as the robot shifts in position, the position reference frame produced by the laser images is correspondingly altered. Using normalization and camera registration techniques presented in this paper, the relative translation and rotation of the robot in 3D are determined from these reference frame transformations.
Examining wildlife responses to phenology and wildfire using a landscape-scale camera trap network
Villarreal, Miguel L.; Gass, Leila; Norman, Laura; Sankeya, Joel B.; Wallace, Cynthia S.A.; McMacken, Dennis; Childs, Jack L.; Petrakis, Roy E.
2012-01-01
Between 2001 and 2009, the Borderlands Jaguar Detection Project deployed 174 camera traps in the mountains of southern Arizona to record jaguar activity. In addition to jaguars, the motion-activated cameras, placed along known wildlife travel routes, recorded occurrences of ~ 20 other animal species. We examined temporal relationships of white-tailed deer (Odocoileus virginianus) and javelina (Pecari tajacu) to landscape phenology (as measured by monthly Normalized Difference Vegetation Index data) and the timing of wildfire (Alambre Fire of 2007). Mixed model analyses suggest that temporal dynamics of these two species were related to vegetation phenology and natural disturbance in the Sky Island region, information important for wildlife managers faced with uncertainty regarding changing climate and disturbance regimes.
Family, maternal, and child health through photovoice.
Wang, Caroline C; Pies, Cheri A
2004-06-01
(1) To introduce photovoice, a participatory action research methodology, for use by MCH program managers to enhance community health assessments and program planning efforts, (2) to enable community people to use the photovoice methodology as a tool to record, reflect, and communicate their family, maternal, and child health assets and concerns, and (3) to educate community leaders about family, maternal, and child health issues from a grassroots perspective. Photovoice is based upon the theoretical literature on education for critical consciousness, feminist theory, and community-based approaches to documentary photography. Picture This Photovoice project took place in Contra Costa, an economically and ethnically diverse county in the San Francisco Bay area. Sixty county residents of ages 13-50 participated in 3 sessions during which they received training from the local health department in the techniques and process of photovoice. Residents were provided with disposable cameras and were encouraged to take photographs reflecting their views on family, maternal, and child health assets and concerns in their community, and then participated in group discussions about their photographs. Community events were held to enable participants to educate MCH staff and community leaders. The photovoice project provided MCH staff with information to supplement existing quantitative perinatal data and contributed to an understanding of key MCH issues that participating community residents would like to see addressed. Participants' concerns centered on the need for safe places for children's recreation and for improvement in the broader community environment within county neighborhoods. Participants' definitions of family, maternal, and child health assets and concerns differed from those that MCH professionals may typically view as MCH issues (low birth weight, maternal mortality, teen pregnancy prevention), which helped MCH program staff to expand priorities and include residents' foremost concerns. MCH professionals can apply photovoice as an innovative participatory research methodology to engage community members in needs assessment, asset mapping, and program planning, and in reaching policy makers to advocate strategies promoting family, maternal, and child health as informed from a grassroots perspective.
ERIC Educational Resources Information Center
George, Belinda Chantelle Richardson
2015-01-01
This phenomenological narrative study was to explore nine elementary teachers' perspectives of the integration of the JASON Project virtual field trip into the science curriculum. Study findings indicated that the teachers saw an increase in student participation when implementing the JASON Project virtual field trip. The most significant findings…
A Project Perspective on Doctoral Studies--A Student Point of View
ERIC Educational Resources Information Center
Backlund, Fredrik
2017-01-01
Purpose: Many doctoral students never obtain a doctoral degree, and many do not finish their studies in time. To promote aspects of effectiveness and efficiency in doctoral studies, the purpose of this paper is to explore a project perspective, more specifically how doctoral students experience their studies in terms of key dimensions of projects.…
The Role of Perspective in Mental Time Travel.
Ansuini, Caterina; Cavallo, Andrea; Pia, Lorenzo; Becchio, Cristina
2016-01-01
Recent years have seen accumulating evidence for the proposition that people process time by mapping it onto a linear spatial representation and automatically "project" themselves on an imagined mental time line. Here, we ask whether people can adopt the temporal perspective of another person when travelling through time. To elucidate similarities and differences between time travelling from one's own perspective or from the perspective of another person, we asked participants to mentally project themselves or someone else (i.e., a coexperimenter) to different time points. Three basic properties of mental time travel were manipulated: temporal location (i.e., where in time the travel originates: past, present, and future), motion direction (either backwards or forwards), and temporal duration (i.e., the distance to travel: one, three, or five years). We found that time travels originating in the present lasted longer in the self- than in the other-perspective. Moreover, for self-perspective, but not for other-perspective, time was differently scaled depending on where in time the travel originated. In contrast, when considering the direction and the duration of time travelling, no dissimilarities between the self- and the other-perspective emerged. These results suggest that self- and other-projection, despite some differences, share important similarities in structure.
Ortensi, Andrea; Panunzi, Andrea; Trombetta, Silvia; Cattaneo, Alberto; Sorrenti, Salvatore; D'Orazi, Valerio
2017-05-01
The aim of this study was to test two different video cameras and recording systems used in thyroid surgery in our Department. This is meant to be an attempt to record the real point of view of the magnified vision of surgeon, so as to make the viewer aware of the difference with the naked eye vision. In this retrospective study, we recorded and compared twenty thyroidectomies performed using loupes magnification and microsurgical technique: ten were recorded with GoPro ® 4 Session action cam (commercially available) and ten with our new prototype of head mounted video camera. Settings were selected before surgery for both cameras. The recording time is about from 1 to 2 h for GoPro ® and from 3 to 5 h for our prototype. The average time of preparation to fit the camera on the surgeon's head and set the functionality is about 5 min for GoPro ® and 7-8 min for the prototype, mostly due to HDMI wiring cable. Videos recorded with the prototype require no further editing, which is mandatory for videos recorded with GoPro ® to highlight the surgical details. the present study showed that our prototype of video camera, compared with GoPro ® 4 Session, guarantees best results in terms of surgical video recording quality, provides to the viewer the exact perspective of the microsurgeon and shows accurately his magnified view through the loupes in thyroid surgery. These recordings are surgical aids for teaching and education and might be a method of self-analysis of surgical technique. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.
Hershberger, W A; Stewart, M R; Laughlin, N K
1976-05-01
Motion projections (pictures) simulating a horizontal array of vertical lines rotating in depth about its central vertical line were observed by 24 college students who rotated a crank handle in the direction of apparent rotation. All displays incorporated contradictory motion perspective: Whereas the perspective transformation in the vertical (y) dimension stimulated one direction of rotation, the transformation in the horizontal (x) dimension simulated the opposite direction. The amount of perspective in each dimension was varied independently of the other by varying the projection ratio used for each dimension. We used the same five ratios for each dimension, combining them factorially to generate the 25 displays. Analysis of variance of the duration of crank turning which agreed with y-axis information yielded main effects of both x and y projection ratios but no interaction, revealing that x- and y-axis motion perspectives mediate kinetic depth effects which are functionally independent.
Comparing artistic and geometrical perspective depictions of space in the visual field
Baldwin, Joseph; Burleigh, Alistair; Pepperell, Robert
2014-01-01
Which is the most accurate way to depict space in our visual field? Linear perspective, a form of geometrical perspective, has traditionally been regarded as the correct method of depicting visual space. But artists have often found it is limited in the angle of view it can depict; wide-angle scenes require uncomfortably close picture viewing distances or impractical degrees of enlargement to be seen properly. Other forms of geometrical perspective, such as fisheye projections, can represent wider views but typically produce pictures in which objects appear distorted. In this study we created an artistic rendering of a hemispherical visual space that encompassed the full visual field. We compared it to a number of geometrical perspective projections of the same space by asking participants to rate which best matched their visual experience. We found the artistic rendering performed significantly better than the geometrically generated projections. PMID:26034563
Comparing artistic and geometrical perspective depictions of space in the visual field.
Baldwin, Joseph; Burleigh, Alistair; Pepperell, Robert
2014-01-01
Which is the most accurate way to depict space in our visual field? Linear perspective, a form of geometrical perspective, has traditionally been regarded as the correct method of depicting visual space. But artists have often found it is limited in the angle of view it can depict; wide-angle scenes require uncomfortably close picture viewing distances or impractical degrees of enlargement to be seen properly. Other forms of geometrical perspective, such as fisheye projections, can represent wider views but typically produce pictures in which objects appear distorted. In this study we created an artistic rendering of a hemispherical visual space that encompassed the full visual field. We compared it to a number of geometrical perspective projections of the same space by asking participants to rate which best matched their visual experience. We found the artistic rendering performed significantly better than the geometrically generated projections.
Hand–eye calibration using a target registration error model
Morgan, Isabella; Jayarathne, Uditha; Ma, Burton; Peters, Terry M.
2017-01-01
Surgical cameras are prevalent in modern operating theatres and are often used as a surrogate for direct vision. Visualisation techniques (e.g. image fusion) made possible by tracking the camera require accurate hand–eye calibration between the camera and the tracking system. The authors introduce the concept of ‘guided hand–eye calibration’, where calibration measurements are facilitated by a target registration error (TRE) model. They formulate hand–eye calibration as a registration problem between homologous point–line pairs. For each measurement, the position of a monochromatic ball-tip stylus (a point) and its projection onto the image (a line) is recorded, and the TRE of the resulting calibration is predicted using a TRE model. The TRE model is then used to guide the placement of the calibration tool, so that the subsequent measurement minimises the predicted TRE. Assessing TRE after each measurement produces accurate calibration using a minimal number of measurements. As a proof of principle, they evaluated guided calibration using a webcam and an endoscopic camera. Their endoscopic camera results suggest that millimetre TRE is achievable when at least 15 measurements are acquired with the tracker sensor ∼80 cm away on the laparoscope handle for a target ∼20 cm away from the camera. PMID:29184657
Mertens, Jan E.J.; Roie, Martijn Van; Merckx, Jonas; Dekoninck, Wouter
2017-01-01
Abstract Digitization of specimen collections has become a key priority of many natural history museums. The camera systems built for this purpose are expensive, providing a barrier in institutes with limited funding, and therefore hampering progress. An assessment is made on whether a low cost compact camera with image stacking functionality can help expedite the digitization process in large museums or provide smaller institutes and amateur entomologists with the means to digitize their collections. Images of a professional setup were compared with the Olympus Stylus TG-4 Tough, a low-cost compact camera with internal focus stacking functions. Parameters considered include image quality, digitization speed, price, and ease-of-use. The compact camera’s image quality, although inferior to the professional setup, is exceptional considering its fourfold lower price point. Producing the image slices in the compact camera is a matter of seconds and when optimal image quality is less of a priority, the internal stacking function omits the need for dedicated stacking software altogether, further decreasing the cost and speeding up the process. In general, it is found that, aware of its limitations, this compact camera is capable of digitizing entomological collections with sufficient quality. As technology advances, more institutes and amateur entomologists will be able to easily and affordably catalogue their specimens. PMID:29134038
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).
Introducing the depth transfer curve for 3D capture system characterization
NASA Astrophysics Data System (ADS)
Goma, Sergio R.; Atanassov, Kalin; Ramachandra, Vikas
2011-03-01
3D technology has recently made a transition from movie theaters to consumer electronic devices such as 3D cameras and camcorders. In addition to what 2D imaging conveys, 3D content also contains information regarding the scene depth. Scene depth is simulated through the strongest brain depth cue, namely retinal disparity. This can be achieved by capturing an image by horizontally separated cameras. Objects at different depths will be projected with different horizontal displacement on the left and right camera images. These images, when fed separately to either eye, leads to retinal disparity. Since the perception of depth is the single most important 3D imaging capability, an evaluation procedure is needed to quantify the depth capture characteristics. Evaluating depth capture characteristics subjectively is a very difficult task since the intended and/or unintended side effects from 3D image fusion (depth interpretation) by the brain are not immediately perceived by the observer, nor do such effects lend themselves easily to objective quantification. Objective evaluation of 3D camera depth characteristics is an important tool that can be used for "black box" characterization of 3D cameras. In this paper we propose a methodology to evaluate the 3D cameras' depth capture capabilities.
Constructing a Database from Multiple 2D Images for Camera Pose Estimation and Robot Localization
NASA Technical Reports Server (NTRS)
Wolf, Michael; Ansar, Adnan I.; Brennan, Shane; Clouse, Daniel S.; Padgett, Curtis W.
2012-01-01
The LMDB (Landmark Database) Builder software identifies persistent image features (landmarks) in a scene viewed multiple times and precisely estimates the landmarks 3D world positions. The software receives as input multiple 2D images of approximately the same scene, along with an initial guess of the camera poses for each image, and a table of features matched pair-wise in each frame. LMDB Builder aggregates landmarks across an arbitrarily large collection of frames with matched features. Range data from stereo vision processing can also be passed to improve the initial guess of the 3D point estimates. The LMDB Builder aggregates feature lists across all frames, manages the process to promote selected features to landmarks, and iteratively calculates the 3D landmark positions using the current camera pose estimations (via an optimal ray projection method), and then improves the camera pose estimates using the 3D landmark positions. Finally, it extracts image patches for each landmark from auto-selected key frames and constructs the landmark database. The landmark database can then be used to estimate future camera poses (and therefore localize a robotic vehicle that may be carrying the cameras) by matching current imagery to landmark database image patches and using the known 3D landmark positions to estimate the current pose.
Fringe projection profilometry with portable consumer devices
NASA Astrophysics Data System (ADS)
Liu, Danji; Pan, Zhipeng; Wu, Yuxiang; Yue, Huimin
2018-01-01
A fringe projection profilometry (FPP) using portable consumer devices is attractive because it can realize optical three dimensional (3D) measurement for ordinary consumers in their daily lives. We demonstrate a FPP using a camera in a smart mobile phone and a digital consumer mini projector. In our experiment of testing the smart phone (iphone7) camera performance, the rare-facing camera in the iphone7 causes the FPP to have a fringe contrast ratio of 0.546, nonlinear carrier phase aberration value of 0.6 rad, and nonlinear phase error of 0.08 rad and RMS random phase error of 0.033 rad. In contrast, the FPP using the industrial camera has a fringe contrast ratio of 0.715, nonlinear carrier phase aberration value of 0.5 rad, nonlinear phase error of 0.05 rad and RMS random phase error of 0.011 rad. Good performance is achieved by using the FPP composed of an iphone7 and a mini projector. 3D information of a facemask with a size for an adult is also measured by using the FPP that uses portable consumer devices. After the system calibration, the 3D absolute information of the facemask is obtained. The measured results are in good agreement with the ones that are carried out in a traditional way. Our results show that it is possible to use portable consumer devices to construct a good FPP, which is useful for ordinary people to get 3D information in their daily lives.
Apollo 11 stereo view showing lump of surface powder with glassy material
1969-07-20
AS11-45-6704 (20 July 1969) --- An Apollo stereo view showing a close-up of a small lump of lunar surface powder about a half inch across, with a splash of a glassy material over it. It seems that a drop of molten material fell on it, splashed and froze. The exposure was made by the Apollo 11 35mm stereo close-up camera. The camera was specially developed to get the highest possible resolution of a small area. A three-inch square area is photographed with a flash illumination and at a fixed distance. The camera is mounted on a walking stick, and the astronauts use it by holding it up against the object to be photographed and pulling the trigger. The pictures are in color and give a stereo view, enabling the fine detail to be seen very clearly. The project is under the direction of Professor T. Gold of Cornell University and Dr. F. Pearce of NASA. The camera was designed and built by Eastman Kodak. Professor E. Purcell of Harvard University and Dr. E. Land of the Polaroid Corporation have contributed to the project. The pictures brought back from the moon by the Apollo 11 crew are of excellent quality and allow fine detail of the undisturbed lunar surface to be seen. Scientists hope to be able to deduce from them some of the processes that have taken place that have shaped and modified the surface.
D Point Cloud Model Colorization by Dense Registration of Digital Images
NASA Astrophysics Data System (ADS)
Crombez, N.; Caron, G.; Mouaddib, E.
2015-02-01
Architectural heritage is a historic and artistic property which has to be protected, preserved, restored and must be shown to the public. Modern tools like 3D laser scanners are more and more used in heritage documentation. Most of the time, the 3D laser scanner is completed by a digital camera which is used to enrich the accurate geometric informations with the scanned objects colors. However, the photometric quality of the acquired point clouds is generally rather low because of several problems presented below. We propose an accurate method for registering digital images acquired from any viewpoints on point clouds which is a crucial step for a good colorization by colors projection. We express this image-to-geometry registration as a pose estimation problem. The camera pose is computed using the entire images intensities under a photometric visual and virtual servoing (VVS) framework. The camera extrinsic and intrinsic parameters are automatically estimated. Because we estimates the intrinsic parameters we do not need any informations about the camera which took the used digital image. Finally, when the point cloud model and the digital image are correctly registered, we project the 3D model in the digital image frame and assign new colors to the visible points. The performance of the approach is proven in simulation and real experiments on indoor and outdoor datasets of the cathedral of Amiens, which highlight the success of our method, leading to point clouds with better photometric quality and resolution.
NASA Technical Reports Server (NTRS)
Galibert, G.
1978-01-01
Aerial and ground photographs of Wallis mountains and of Dolomiti di Cortina d'Ampezzo in Italy were made using spectrozonal emulsions and optical multichannel filters. A metric camera was used in the perspective of the first Spacelab flight aboard the space shuttle. Elementary forms of alpine geomorphology and ice or snow phenomena are detectable on these metric scenes.
AMORE; The Advanced Multimedia Organizer for Requirements Elicitation
1993-06-01
terms of cinematic primitives, including: perspective, camera, sound, content, and context [Davenport 91]. Ambient sound can be used to provide...concept) [Dumais 88], [Salton 83]. Latent semantic indexing [Dumais 88] could improve the access to video shots described by cinematic primitives. As...into classes (includ- the cited articles) video source ing cinematic primi- tives) CMU/SEI-93-TR-12 33 A.6 Tree-Maps Retrieval Visualization
ERIC Educational Resources Information Center
Walker, Barbara M.
This paper reports on an integrated methodology adopted to help solve the problem of accessing boys' fleeting, mobile, and often unvoiced self-work during the process of constructing their gender identity. The study is part of a larger investigation examining the experience and education of boys and young men in relation to matters of sexual…
ERIC Educational Resources Information Center
Moyer, Judith; Onosko, Joseph; Forcey, Charles; Cobb, Casey
2003-01-01
This article discusses the History in Perspective Project (HIP), a collaborative project between the University of New Hampshire (UNH), its Supervisory Administration Unit #56 (SAU #56), and 13 other school districts. The authors' three-pronged plan was simple, straightforward, and, in some ways, experimental. From observation and experience, they…
The Implementation of Project Citizen in Bolivian Schools: Perspectives from Three Teacher Educators
ERIC Educational Resources Information Center
Medina-Jerez, William; Taylor, Carolyn; Bryant, Carol
2009-01-01
The central aim of the present paper is to examine, from the Social Studies, Modern Languages, and Science Education perspectives, the role of the Project Citizen initiative in school communities of Bolivia. To that end, Project Citizen in Bolivia, during its first three years of implementation will be discussed, followed by views from each field…
BEGIRA: Basque Educational Gate for Interactive and Remote Astronomy
NASA Astrophysics Data System (ADS)
Gorosabel, J.; Sánchez-Lavega, A.; Pérez Hoyos, S.; Hueso, R.
2015-05-01
The BEGIRA project consists in making available the 1.23 m Calar Alto (CAHA) telescope to students of the University of the Basque Country (UPV/EHU). The project is designed in such a way that undergraduate and graduate students of the Máster oficial en ciencia y tecnología espacial of the UPV/EHU can control remotely the 1.23 m CAHA telescope. The instrument used is the DLR camera, which based on its large field of view and high sensitivity, allows observations ranging from nearby solar system bodies to remote gamma-ray bursts. The students are also responsible of reducing and analyzing the resultant DLR data. The observations are conducted from the Aula Espazio Gela located at the Faculty of Engineering at Bilbao. The students can control remotely i) the 1.23 m telescope, ii) the DLR camera and iii) the autoguider. They have also continuous access to the observatory weather station, webcams, astrometric tools and the CAHA archive, so they can actually see in real-time what they are doing. The operations can be visualized by two light cannons which display the telescope and camera controls for the audience. In case of any emergency the students are backed up by the CAHA staff. The BEGIRA project shows the potential that remote control of professional telescopes has for educational purposes. As proven by the several discoveries carried out under BEGIRA, the educational activities can be complemented with cutting-edge research activities carried out by Master Students. In the coming years we plan to continue with the BEGIRA project. More information can be found at http://www.ehu.es/aula-espazio/begira/.
Color Imaging management in film processing
NASA Astrophysics Data System (ADS)
Tremeau, Alain; Konik, Hubert; Colantoni, Philippe
2003-12-01
The latest research projects in the laboratory LIGIV concerns capture, processing, archiving and display of color images considering the trichromatic nature of the Human Vision System (HSV). Among these projects one addresses digital cinematographic film sequences of high resolution and dynamic range. This project aims to optimize the use of content for the post-production operators and for the end user. The studies presented in this paper address the use of metadata to optimise the consumption of video content on a device of user's choice independent of the nature of the equipment that captured the content. Optimising consumption includes enhancing the quality of image reconstruction on a display. Another part of this project addresses the content-based adaptation of image display. Main focus is on Regions of Interest (ROI) operations, based on the ROI concepts of MPEG-7. The aim of this second part is to characterize and ensure the conditions of display even if display device or display media changes. This requires firstly the definition of a reference color space and the definition of bi-directional color transformations for each peripheral device (camera, display, film recorder, etc.). The complicating factor is that different devices have different color gamuts, depending on the chromaticity of their primaries and the ambient illumination under which they are viewed. To match the displayed image to the aimed appearance, all kind of production metadata (camera specification, camera colour primaries, lighting conditions) should be associated to the film material. Metadata and content build together rich content. The author is assumed to specify conditions as known from digital graphics arts. To control image pre-processing and image post-processing, these specifications should be contained in the film's metadata. The specifications are related to the ICC profiles but need additionally consider mesopic viewing conditions.
Vigie Ciel a collaborative project to study fireballs and organise meteorite recoveries
NASA Astrophysics Data System (ADS)
Colas, F.; Zanda, B.; Bouley, S.; Lewin, E.; Vaubaillon, J.; Marmo, C.; Rotaru, M.; Labenne, L.; Julien, J. F.; Linares, M.; Steinhausser, A.; Rault, J. L.; Vernazza, P.
2015-10-01
Research on fireballs and meteorites has always been of interest to the public, due to the beauty of shooting stars in the night sky and to the extraterrestrial origin of meteorites. A fireball observation network called FRIPON [1] (Colas et al, 2015) is currently being setup, funded by ANR (Agence Nationale pour la Recherche). It will cover France with 100 cameras and is expected to be operational for the end of 2015. FRIPON will detect fireballs and hence allow us to define meteorite strewn fields within 24h, so that meteorite searches can be launched very early on. Because of the need to search all over France, including in private land, it is important that the general public be aware of our project and be willing to help or participate. Indeed, as the main goal of FRIPON is to recover fresh meteorites (within a few days), our aim is to be able to organize a search with at least 50 persons to scan an area of a few km2 within a week. Help from the public would hence be most helpful but it is also important to have an operational and trained research team. This project thus appears as a unique occasion to involve the public in a scientific project while promoting informal scientific education. This prompted us to set up Vigie-Ciel, a citizen science network centered on meteorite recovery. FRIPON is an open network based on open-source software, it will accept citizenrun cameras. In addition to fireballs, it will allow scientists and Vigie-Ciel participants to study anything that can be observed by all-sky cameras: bird migrations, bats, clouds, lightning, etc. The data will be freely available to all.
BRDF-dependent accuracy of array-projection-based 3D sensors.
Heist, Stefan; Kühmstedt, Peter; Tünnermann, Andreas; Notni, Gunther
2017-03-10
In order to perform high-speed three-dimensional (3D) shape measurements with structured light systems, high-speed projectors are required. One possibility is an array projector, which allows pattern projection at several tens of kilohertz by switching on and off the LEDs of various slide projectors. The different projection centers require a separate analysis, as the intensity received by the cameras depends on the projection direction and the object's bidirectional reflectance distribution function (BRDF). In this contribution, we investigate the BRDF-dependent errors of array-projection-based 3D sensors and propose an error compensation process.
The Identification and Modeling of Visual Cue Usage in Manual Control Task Experiments
NASA Technical Reports Server (NTRS)
Sweet, Barbara Townsend; Trejo, Leonard J. (Technical Monitor)
1999-01-01
Many fields of endeavor require humans to conduct manual control tasks while viewing a perspective scene. Manual control refers to tasks in which continuous, or nearly continuous, control adjustments are required. Examples include flying an aircraft, driving a car, and riding a bicycle. Perspective scenes can arise through natural viewing of the world, simulation of a scene (as in flight simulators), or through imaging devices (such as the cameras on an unmanned aerospace vehicle). Designers frequently have some degree of control over the content and characteristics of a perspective scene; airport designers can choose runway markings, vehicle designers can influence the size and shape of windows, as well as the location of the pilot, and simulator database designers can choose scene complexity and content. Little theoretical framework exists to help designers determine the answers to questions related to perspective scene content. An empirical approach is most commonly used to determine optimum perspective scene configurations. The goal of the research effort described in this dissertation has been to provide a tool for modeling the characteristics of human operators conducting manual control tasks with perspective-scene viewing. This is done for the purpose of providing an algorithmic, as opposed to empirical, method for analyzing the effects of changing perspective scene content for closed-loop manual control tasks.
2012-08-17
The Curiosity engineering team created this cylindrical projection view from images taken by NASA Curiosity rover front hazard avoidance cameras underneath the rover deck on Sol 0. Pictured here are are the pigeon-toed the wheels.
ERIC Educational Resources Information Center
Clarke, Doug; Clarke, David; Roche, Anne; Chan, Man Ching Esther
2015-01-01
A central premise of this project is that teachers learn from the act of teaching a lesson and that this learning is evident in the planning and teaching of a subsequent lesson. In this project, the knowledge construction of mathematics teachers was examined utilising multi-camera research techniques during lesson planning, classroom interactions…
ERIC Educational Resources Information Center
Ford, Faye, Ed.
This book describes 119 award-winning projects from a program which established a national teachers' competition to select and disseminate superior teacher-planned and developed programs which use photography as an integral part of the K-12 school curriculum. All subject areas, grade levels, and states are represented in summaries of projects that…
UTOFIA: an underwater time-of-flight image acquisition system
NASA Astrophysics Data System (ADS)
Driewer, Adrian; Abrosimov, Igor; Alexander, Jonathan; Benger, Marc; O'Farrell, Marion; Haugholt, Karl Henrik; Softley, Chris; Thielemann, Jens T.; Thorstensen, Jostein; Yates, Chris
2017-10-01
In this article the development of a newly designed Time-of-Flight (ToF) image sensor for underwater applications is described. The sensor is developed as part of the project UTOFIA (underwater time-of-flight image acquisition) funded by the EU within the Horizon 2020 framework. This project aims to develop a camera based on range gating that extends the visible range compared to conventional cameras by a factor of 2 to 3 and delivers real-time range information by means of a 3D video stream. The principle of underwater range gating as well as the concept of the image sensor are presented. Based on measurements on a test image sensor a pixel structure that suits best to the requirements has been selected. Within an extensive characterization underwater the capability of distance measurements in turbid environments is demonstrated.
Soft x-ray reduction camera for submicron lithography
Hawryluk, A.M.; Seppala, L.G.
1991-03-26
Soft x-ray projection lithography can be performed using x-ray optical components and spherical imaging lenses (mirrors), which form an x-ray reduction camera. The x-ray reduction is capable of projecting a 5x demagnified image of a mask onto a resist coated wafer using 4.5 nm radiation. The diffraction limited resolution of this design is about 135 nm with a depth of field of about 2.8 microns and a field of view of 0.2 cm[sup 2]. X-ray reflecting masks (patterned x-ray multilayer mirrors) which are fabricated on thick substrates and can be made relatively distortion free are used, with a laser produced plasma for the source. Higher resolution and/or larger areas are possible by varying the optic figures of the components and source characteristics. 9 figures.
Canessa, Andrea; Gibaldi, Agostino; Chessa, Manuela; Fato, Marco; Solari, Fabio; Sabatini, Silvio P.
2017-01-01
Binocular stereopsis is the ability of a visual system, belonging to a live being or a machine, to interpret the different visual information deriving from two eyes/cameras for depth perception. From this perspective, the ground-truth information about three-dimensional visual space, which is hardly available, is an ideal tool both for evaluating human performance and for benchmarking machine vision algorithms. In the present work, we implemented a rendering methodology in which the camera pose mimics realistic eye pose for a fixating observer, thus including convergent eye geometry and cyclotorsion. The virtual environment we developed relies on highly accurate 3D virtual models, and its full controllability allows us to obtain the stereoscopic pairs together with the ground-truth depth and camera pose information. We thus created a stereoscopic dataset: GENUA PESTO—GENoa hUman Active fixation database: PEripersonal space STereoscopic images and grOund truth disparity. The dataset aims to provide a unified framework useful for a number of problems relevant to human and computer vision, from scene exploration and eye movement studies to 3D scene reconstruction. PMID:28350382
Mash, Bob; Powell, Di; du Plessis, Felicity; van Vuuren, Unita; Michalowska, Margaret; Levitt, Naomi
2007-12-01
In South Africa diabetes makes a significant contribution to the burden of disease. Diabetic retinopathy is a leading cause of adult blindness, and screening can reduce the incidence. This project aimed to implement and evaluate a new service for retinal screening that uses a non-mydriatic mobile fundal camera in primary care. This is the first time such a service has been evaluated in an African primary care context. The service was implemented as an operational research study at three community health centres and data were collected to evaluate the operational issues, screening, reporting and referral of patients. Out of 400 patients screened 84% had a significantly reduced visual acuity, 63% had retinopathy (22% severe nonproliferative, 6% proliferative and 15% maculopathy), 2% of eyes could not be screened and 14% of patients required dilatation. Referral was necessary in 27% of cases for cataracts, in 7% for laser treatment and in 4% for other specialist services. Repeat photography was needed in 8% and urgent follow-up in 12%. A SWOT analysis of the pilot project was completed and recommendations were made on how to integrate it into the district health system. Screening with a fundal camera improved the quality of care for diabetic patients and is feasible in the South African public sector, primary care setting. A single technician should be able to photograph almost 10,000 patients a year.
NASA Astrophysics Data System (ADS)
Feng, Shijie; Chen, Qian; Zuo, Chao; Sun, Jiasong; Yu, Shi Ling
2014-10-01
Optical three-dimensional (3-D) profilometry is gaining increasing attention for its simplicity, flexibility, high accuracy, and non-contact nature. Recent advances in imaging sensors and digital projection technology further its progress in high-speed, real-time applications, enabling 3-D shapes reconstruction of moving objects and dynamic scenes. However, the camera lens is never perfect and the lens distortion does influence the accuracy of the measurement result, which is often overlooked in the existing real-time 3-D shape measurement systems. To this end, here we present a novel high-speed real-time 3-D coordinates measuring technique based on fringe projection with the consideration of the camera lens distortion. A pixel mapping relation between a distorted image and a corrected one is pre-determined and stored in computer memory for real-time fringe correction. The out-of-plane height is obtained firstly and the acquisition for the two corresponding in-plane coordinates follows on the basis of the solved height. Besides, a method of lookup table (LUT) is introduced as well for fast data processing. Our experimental results reveal that the measurement error of the in-plane coordinates has been reduced by one order of magnitude and the accuracy of the out-plane coordinate been tripled after the distortions being eliminated. Moreover, owing to the generated LUTs, a 3-D reconstruction speed of 92.34 frames per second can be achieved.
Deviation rectification for dynamic measurement of rail wear based on coordinate sets projection
NASA Astrophysics Data System (ADS)
Wang, Chao; Ma, Ziji; Li, Yanfu; Zeng, Jiuzhen; Jin, Tan; Liu, Hongli
2017-10-01
Dynamic measurement of rail wear using a laser imaging system suffers from random vibrations in the laser-based imaging sensor which cause distorted rail profiles. In this paper, a simple and effective method for rectifying profile deviation is presented to address this issue. There are two main steps: profile recognition and distortion calibration. According to the constant camera and projector parameters, efficient recognition of measured profiles is achieved by analyzing the geometric difference between normal profiles and distorted ones. For a distorted profile, by constructing coordinate sets projecting from it to the standard one on triple projecting primitives, including the rail head inner line, rail waist curve and rail jaw, iterative extrinsic camera parameter self-compensation is implemented. The distortion is calibrated by projecting the distorted profile onto the x-y plane of a measuring coordinate frame, which is parallel to the rail cross section, to eliminate the influence of random vibrations in the laser-based imaging sensor. As well as evaluating the implementation with comprehensive experiments, we also compare our method with other published works. The results exhibit the effectiveness and superiority of our method for the dynamic measurement of rail wear.
Opportunity's View After Drive on Sol 1806 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11816 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11816 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, full-circle view of the rover's surroundings just after driving 60.86 meters (200 feet) on the 1,806th Martian day, or sol, of Opportunity's surface mission (Feb. 21, 2009). North is at the center; south at both ends. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Engineers designed the Sol 1806 drive to be driven backwards as a strategy to redistribute lubricant in the rovers wheels. The right-front wheel had been showing signs of increased friction. The rover's position after the Sol 1806 drive was about 2 kilometer (1.2 miles) south southwest of Victoria Crater. Cumulative odometry was 14.74 kilometers (9.16 miles) since landing in January 2004, including 2.96 kilometers (1.84 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a cylindrical-perspective projection with geometric seam correction.Opportunity's View After Long Drive on Sol 1770 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11791 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11791 NASA's Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, full-circle view of the rover's surroundings just after driving 104 meters (341 feet) on the 1,770th Martian day, or sol, of Opportunity's surface mission (January 15, 2009). This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. Tracks from the drive extend northward across dark-toned sand ripples and light-toned patches of exposed bedrock in the Meridiani Planum region of Mars. For scale, the distance between the parallel wheel tracks is about 1 meter (about 40 inches). Prior to the Sol 1770 drive, Opportunity had driven less than a meter since Sol 1713 (November 17, 2008), while it used the tools on its robotic arm first to examine a meteorite called 'Santorini' during weeks of restricted communication while the sun was nearly in line between Mars and Earth, then to examine bedrock and soil targets near Santorini. The rover's position after the Sol 1770 drive was about 1.1 kilometer (two-thirds of a mile) south southwest of Victoria Crater. Cumulative odometry was 13.72 kilometers (8.53 miles) since landing in January 2004, including 1.94 kilometers (1.21 miles) since climbing out of Victoria Crater on the west side of the crater on Sol 1634 (August 28, 2008). This view is presented as a cylindrical-perspective projection with geometric seam correction.Opportunity View During Exploration in 'Duck Bay,' Sols 1506-1510 (Stereo)
NASA Technical Reports Server (NTRS)
2009-01-01
[figure removed for brevity, see original site] Left-eye view of a color stereo pair for PIA11787 [figure removed for brevity, see original site] Right-eye view of a color stereo pair for PIA11787 NASA Mars Exploration Rover Opportunity used its navigation camera to take the images combined into this stereo, full-circle view of the rover's surroundings on the 1,506th through 1,510th Martian days, or sols, of Opportunity's mission on Mars (April 19-23, 2008). North is at the top. This view combines images from the left-eye and right-eye sides of the navigation camera. It appears three-dimensional when viewed through red-blue glasses with the red lens on the left. The site is within an alcove called 'Duck Bay' in the western portion of Victoria Crater. Victoria Crater is about 800 meters (half a mile) wide. Opportunity had descended into the crater at the top of Duck Bay 7 months earlier. By the time the rover acquired this view, it had examined rock layers inside the rim. Opportunity was headed for a closer look at the base of a promontory called 'Cape Verde,' the cliff at about the 2-o'clock position of this image, before leaving Victoria. The face of Cape Verde is about 6 meters (20 feet) tall. Just clockwise from Cape Verde is the main bowl of Victoria Crater, with sand dunes at the bottom. A promontory called 'Cabo Frio,' at the southern side of Duck Bay, stands near the 6-o'clock position of the image. This view is presented as a cylindrical-perspective projection with geometric seam correction.NASA Astrophysics Data System (ADS)
Abookasis, David; Moshe, Tomer
2014-11-01
This paper demonstrates the insertion of lens array in the front of a CCD camera in a laser speckle imaging (LSI) like-technique to acquire multiple speckle reflectance projections for imaging blood flow in an intact biological tissue. In some of LSI applications, flow imaging is obtained by thinning or removing of the upper tissue layers to access blood vessels. In contrast, with the proposed approach flow imaging can be achieved while the tissue is intact. In the system, each lens from an hexagonal lens array observed the sample from slightly different perspectives and captured with a CCD camera. In the computer, these multiview raw images are converted to speckled contrast maps. Then, a self-deconvolution shift-and-add algorithm is employed for processing yields high contrast flow information. The method is experimentally validated first with a plastic tube filled with scattering liquid running at different controlled flow rates hidden in a biological tissue and then extensively tested for imaging of cerebral blood flow in an intact rodent head experience different conditions. A total of fifteen mice were used in the experiments divided randomly into three groups as follows: Group 1 (n=5) consisted of injured mice experience hypoxic ischemic brain injury monitored for ~40 min. Group 2 (n=5) injured mice experience anoxic brain injury monitored up to 20 min. Group 3 (n=5) experience functional activation monitored up to ~35 min. To increase tissue transparency and the penetration depth of photons through head tissue layers, an optical clearing method was employed. To our knowledge, this work presents for the first time the use of lens array in LSI scheme.
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
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)
Nakagawa, M.; Akano, K.; Kobayashi, T.; Sekiguchi, Y.
2017-09-01
Image-based virtual reality (VR) is a virtual space generated with panoramic images projected onto a primitive model. In imagebased VR, realistic VR scenes can be generated with lower rendering cost, and network data can be described as relationships among VR scenes. The camera network data are generated manually or by an automated procedure using camera position and rotation data. When panoramic images are acquired in indoor environments, network data should be generated without Global Navigation Satellite Systems (GNSS) positioning data. Thus, we focused on image-based VR generation using a panoramic camera in indoor environments. We propose a methodology to automate network data generation using panoramic images for an image-based VR space. We verified and evaluated our methodology through five experiments in indoor environments, including a corridor, elevator hall, room, and stairs. We confirmed that our methodology can automatically reconstruct network data using panoramic images for image-based VR in indoor environments without GNSS position data.
NASA Astrophysics Data System (ADS)
Santos, C. Almeida; Costa, C. Oliveira; Batista, J.
2016-05-01
The paper describes a kinematic model-based solution to estimate simultaneously the calibration parameters of the vision system and the full-motion (6-DOF) of large civil engineering structures, namely of long deck suspension bridges, from a sequence of stereo images captured by digital cameras. Using an arbitrary number of images and assuming a smooth structure motion, an Iterated Extended Kalman Filter is used to recursively estimate the projection matrices of the cameras and the structure full-motion (displacement and rotation) over time, helping to meet the structure health monitoring fulfilment. Results related to the performance evaluation, obtained by numerical simulation and with real experiments, are reported. The real experiments were carried out in indoor and outdoor environment using a reduced structure model to impose controlled motions. In both cases, the results obtained with a minimum setup comprising only two cameras and four non-coplanar tracking points, showed a high accuracy results for on-line camera calibration and structure full motion estimation.
Single-Camera Stereoscopy Setup to Visualize 3D Dusty Plasma Flows
NASA Astrophysics Data System (ADS)
Romero-Talamas, C. A.; Lemma, T.; Bates, E. M.; Birmingham, W. J.; Rivera, W. F.
2016-10-01
A setup to visualize and track individual particles in multi-layered dusty plasma flows is presented. The setup consists of a single camera with variable frame rate, and a pair of adjustable mirrors that project the same field of view from two different angles to the camera, allowing for three-dimensional tracking of particles. Flows are generated by inclining the plane in which the dust is levitated using a specially designed setup that allows for external motion control without compromising vacuum. Dust illumination is achieved with an optics arrangement that includes a Powell lens that creates a laser fan with adjustable thickness and with approximately constant intensity everywhere. Both the illumination and the stereoscopy setup allow for the camera to be placed at right angles with respect to the levitation plane, in preparation for magnetized dusty plasma experiments in which there will be no direct optical access to the levitation plane. Image data and analysis of unmagnetized dusty plasma flows acquired with this setup are presented.
Light field geometry of a Standard Plenoptic Camera.
Hahne, Christopher; Aggoun, Amar; Haxha, Shyqyri; Velisavljevic, Vladan; Fernández, Juan Carlos Jácome
2014-11-03
The Standard Plenoptic Camera (SPC) is an innovation in photography, allowing for acquiring two-dimensional images focused at different depths, from a single exposure. Contrary to conventional cameras, the SPC consists of a micro lens array and a main lens projecting virtual lenses into object space. For the first time, the present research provides an approach to estimate the distance and depth of refocused images extracted from captures obtained by an SPC. Furthermore, estimates for the position and baseline of virtual lenses which correspond to an equivalent camera array are derived. On the basis of paraxial approximation, a ray tracing model employing linear equations has been developed and implemented using Matlab. The optics simulation tool Zemax is utilized for validation purposes. By designing a realistic SPC, experiments demonstrate that a predicted image refocusing distance at 3.5 m deviates by less than 11% from the simulation in Zemax, whereas baseline estimations indicate no significant difference. Applying the proposed methodology will enable an alternative to the traditional depth map acquisition by disparity analysis.
Advanced imaging research and development at DARPA
NASA Astrophysics Data System (ADS)
Dhar, Nibir K.; Dat, Ravi
2012-06-01
Advances in imaging technology have huge impact on our daily lives. Innovations in optics, focal plane arrays (FPA), microelectronics and computation have revolutionized camera design. As a result, new approaches to camera design and low cost manufacturing is now possible. These advances are clearly evident in visible wavelength band due to pixel scaling, improvements in silicon material and CMOS technology. CMOS cameras are available in cell phones and many other consumer products. Advances in infrared imaging technology have been slow due to market volume and many technological barriers in detector materials, optics and fundamental limits imposed by the scaling laws of optics. There is of course much room for improvements in both, visible and infrared imaging technology. This paper highlights various technology development projects at DARPA to advance the imaging technology for both, visible and infrared. Challenges and potentials solutions are highlighted in areas related to wide field-of-view camera design, small pitch pixel, broadband and multiband detectors and focal plane arrays.
Improved CPAS Photogrammetric Capabilities for Engineering Development Unit (EDU) Testing
NASA Technical Reports Server (NTRS)
Ray, Eric S.; Bretz, David R.
2013-01-01
This paper focuses on two key improvements to the photogrammetric analysis capabilities of the Capsule Parachute Assembly System (CPAS) for the Orion vehicle. The Engineering Development Unit (EDU) system deploys Drogue and Pilot parachutes via mortar, where an important metric is the muzzle velocity. This can be estimated using a high speed camera pointed along the mortar trajectory. The distance to the camera is computed from the apparent size of features of known dimension. This method was validated with a ground test and compares favorably with simulations. The second major photogrammetric product is measuring the geometry of the Main parachute cluster during steady-state descent using onboard cameras. This is challenging as the current test vehicles are suspended by a single-point attachment unlike earlier stable platforms suspended under a confluence fitting. The mathematical modeling of fly-out angles and projected areas has undergone significant revision. As the test program continues, several lessons were learned about optimizing the camera usage, installation, and settings to obtain the highest quality imagery possible.
Design of a high-numerical-aperture digital micromirror device camera with high dynamic range.
Qiao, Yang; Xu, Xiping; Liu, Tao; Pan, Yue
2015-01-01
A high-NA imaging system with high dynamic range is presented based on a digital micromirror device (DMD). The DMD camera consists of an objective imaging system and a relay imaging system, connected by a DMD chip. With the introduction of a total internal reflection prism system, the objective imaging system is designed with a working F/# of 1.97, breaking through the F/2.45 limitation of conventional DMD projection lenses. As for the relay imaging system, an off-axis design that could correct off-axis aberrations of the tilt relay imaging system is developed. This structure has the advantage of increasing the NA of the imaging system while maintaining a compact size. Investigation revealed that the dynamic range of a DMD camera could be greatly increased, by 2.41 times. We built one prototype DMD camera with a working F/# of 1.23, and the field experiments proved the validity and reliability our work.
A Structured Light Sensor System for Tree Inventory
NASA Technical Reports Server (NTRS)
Chien, Chiun-Hong; Zemek, Michael C.
2000-01-01
Tree Inventory is referred to measurement and estimation of marketable wood volume in a piece of land or forest for purposes such as investment or for loan applications. Exist techniques rely on trained surveyor conducting measurements manually using simple optical or mechanical devices, and hence are time consuming subjective and error prone. The advance of computer vision techniques makes it possible to conduct automatic measurements that are more efficient, objective and reliable. This paper describes 3D measurements of tree diameters using a uniquely designed ensemble of two line laser emitters rigidly mounted on a video camera. The proposed laser camera system relies on a fixed distance between two parallel laser planes and projections of laser lines to calculate tree diameters. Performance of the laser camera system is further enhanced by fusion of information induced from structured lighting and that contained in video images. Comparison will be made between the laser camera sensor system and a stereo vision system previously developed for measurements of tree diameters.
[Virtual reality in ophthalmological education].
Wagner, C; Schill, M; Hennen, M; Männer, R; Jendritza, B; Knorz, M C; Bender, H J
2001-04-01
We present a computer-based medical training workstation for the simulation of intraocular eye surgery. The surgeon manipulates two original instruments inside a mechanical model of the eye. The instrument positions are tracked by CCD cameras and monitored by a PC which renders the scenery using a computer-graphic model of the eye and the instruments. The simulator incorporates a model of the operation table, a mechanical eye, three CCD cameras for the position tracking, the stereo display, and a computer. The three cameras are mounted under the operation table from where they can observe the interior of the mechanical eye. Using small markers the cameras recognize the instruments and the eye. Their position and orientation in space is determined by stereoscopic back projection. The simulation runs with more than 20 frames per second and provides a realistic impression of the surgery. It includes the cold light source which can be moved inside the eye and the shadow of the instruments on the retina which is important for navigational purposes.
Projecting range-wide sun bear population trends using tree cover and camera-trap bycatch data.
Scotson, Lorraine; Fredriksson, Gabriella; Ngoprasert, Dusit; Wong, Wai-Ming; Fieberg, John
2017-01-01
Monitoring population trends of threatened species requires standardized techniques that can be applied over broad areas and repeated through time. Sun bears Helarctos malayanus are a forest dependent tropical bear found throughout most of Southeast Asia. Previous estimates of global population trends have relied on expert opinion and cannot be systematically replicated. We combined data from 1,463 camera traps within 31 field sites across sun bear range to model the relationship between photo catch rates of sun bears and tree cover. Sun bears were detected in all levels of tree cover above 20%, and the probability of presence was positively associated with the amount of tree cover within a 6-km2 buffer of the camera traps. We used the relationship between catch rates and tree cover across space to infer temporal trends in sun bear abundance in response to tree cover loss at country and global-scales. Our model-based projections based on this "space for time" substitution suggested that sun bear population declines associated with tree cover loss between 2000-2014 in mainland southeast Asia were ~9%, with declines highest in Cambodia and lowest in Myanmar. During the same period, sun bear populations in insular southeast Asia (Malaysia, Indonesia and Brunei) were projected to have declined at a much higher rate (22%). Cast forward over 30-years, from the year 2000, by assuming a constant rate of change in tree cover, we projected population declines in the insular region that surpassed 50%, meeting the IUCN criteria for endangered if sun bears were listed on the population level. Although this approach requires several assumptions, most notably that trends in abundance across space can be used to infer temporal trends, population projections using remotely sensed tree cover data may serve as a useful alternative (or supplement) to expert opinion. The advantages of this approach is that it is objective, data-driven, repeatable, and it requires that all assumptions be clearly stated.
High spatial resolution infrared camera as ISS external experiment
NASA Astrophysics Data System (ADS)
Eckehard, Lorenz; Frerker, Hap; Fitch, Robert Alan
High spatial resolution infrared camera as ISS external experiment for monitoring global climate changes uses ISS internal and external resources (eg. data storage). The optical experiment will consist of an infrared camera for monitoring global climate changes from the ISS. This technology was evaluated by the German small satellite mission BIRD and further developed in different ESA projects. Compared to BIRD the presended instrument uses proven sensor advanced technologies (ISS external) and ISS on board processing and storage capabili-ties (internal). The instrument will be equipped with a serial interfaces for TM/TC and several relay commands for the power supply. For data processing and storage a mass memory is re-quired. The access to actual attitude data is highly desired to produce geo referenced maps-if possible by an on board processing.
Image acquisition in the Pi-of-the-Sky project
NASA Astrophysics Data System (ADS)
Jegier, M.; Nawrocki, K.; Poźniak, K.; Sokołowski, M.
2006-10-01
Modern astronomical image acquisition systems dedicated for sky surveys provide large amount of data in a single measurement session. During one session that lasts a few hours it is possible to get as much as 100 GB of data. This large amount of data needs to be transferred from camera and processed. This paper presents some aspects of image acquisition in a sky survey image acquisition system. It describes a dedicated USB linux driver for the first version of the "Pi of The Sky" CCD camera (later versions have also Ethernet interface) and the test program for the camera together with a driver-wrapper providing core device functionality. Finally, the paper contains description of an algorithm for matching several images based on image features, i.e. star positions and their brightness.
Spacecraft hazard avoidance utilizing structured light
NASA Technical Reports Server (NTRS)
Liebe, Carl Christian; Padgett, Curtis; Chapsky, Jacob; Wilson, Daniel; Brown, Kenneth; Jerebets, Sergei; Goldberg, Hannah; Schroeder, Jeffrey
2006-01-01
At JPL, a <5 kg free-flying micro-inspector spacecraft is being designed for host-vehicle inspection. The spacecraft includes a hazard avoidance sensor to navigate relative to the vehicle being inspected. Structured light was selected for hazard avoidance because of its low mass and cost. Structured light is a method of remote sensing 3-dimensional structure of the proximity utilizing a laser, a grating, and a single regular APS camera. The laser beam is split into 400 different beams by a grating to form a regular spaced grid of laser beams that are projected into the field of view of an APS camera. The laser source and the APS camera are separated forming the base of a triangle. The distance to all beam intersections of the host are calculated based on triangulation.
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.
Miniaturized Autonomous Extravehicular Robotic Camera (Mini AERCam)
NASA Technical Reports Server (NTRS)
Fredrickson, Steven E.
2001-01-01
The NASA Johnson Space Center (JSC) Engineering Directorate is developing the Autonomous Extravehicular Robotic Camera (AERCam), a low-volume, low-mass free-flying camera system . AERCam project team personnel recently initiated development of a miniaturized version of AERCam known as Mini AERCam. The Mini AERCam target design is a spherical "nanosatellite" free-flyer 7.5 inches in diameter and weighing 1 0 pounds. Mini AERCam is building on the success of the AERCam Sprint STS-87 flight experiment by adding new on-board sensing and processing capabilities while simultaneously reducing volume by 80%. Achieving enhanced capability in a smaller package depends on applying miniaturization technology across virtually all subsystems. Technology innovations being incorporated include micro electromechanical system (MEMS) gyros, "camera-on-a-chip" CMOS imagers, rechargeable xenon gas propulsion system , rechargeable lithium ion battery, custom avionics based on the PowerPC 740 microprocessor, GPS relative navigation, digital radio frequency communications and tracking, micropatch antennas, digital instrumentation, and dense mechanical packaging. The Mini AERCam free-flyer will initially be integrated into an approximate flight-like configuration for demonstration on an airbearing table. A pilot-in-the-loop and hardware-in-the-loop simulation to simulate on-orbit navigation and dynamics will complement the airbearing table demonstration. The Mini AERCam lab demonstration is intended to form the basis for future development of an AERCam flight system that provides beneficial on-orbit views unobtainable from fixed cameras, cameras on robotic manipulators, or cameras carried by EVA crewmembers.
Optimum color filters for CCD digital cameras
NASA Astrophysics Data System (ADS)
Engelhardt, Kai; Kunz, Rino E.; Seitz, Peter; Brunner, Harald; Knop, Karl
1993-12-01
As part of the ESPRIT II project No. 2103 (MASCOT) a high performance prototype color CCD still video camera was developed. Intended for professional usage such as in the graphic arts, the camera provides a maximum resolution of 3k X 3k full color pixels. A high colorimetric performance was achieved through specially designed dielectric filters and optimized matrixing. The color transformation was obtained by computer simulation of the camera system and non-linear optimization which minimized the perceivable color errors as measured in the 1976 CIELUV uniform color space for a set of about 200 carefully selected test colors. The color filters were designed to allow perfect colorimetric reproduction in principle and at the same time with imperceptible color noise and with special attention to fabrication tolerances. The camera system includes a special real-time digital color processor which carries out the color transformation. The transformation can be selected from a set of sixteen matrices optimized for different illuminants and output devices. Because the actual filter design was based on slightly incorrect data the prototype camera showed a mean colorimetric error of 2.7 j.n.d. (CIELUV) in experiments. Using correct input data in the redesign of the filters, a mean colorimetric error of only 1 j.n.d. (CIELUV) seems to be feasible, implying that it is possible with such an optimized color camera to achieve such a high colorimetric performance that the reproduced colors in an image cannot be distinguished from the original colors in a scene, even in direct comparison.
Volunteers Help Decide Where to Point Mars Camera
2015-07-22
This series of images from NASA's Mars Reconnaissance Orbiter successively zooms into "spider" features -- or channels carved in the surface in radial patterns -- in the south polar region of Mars. In a new citizen-science project, volunteers will identify features like these using wide-scale images from the orbiter. Their input will then help mission planners decide where to point the orbiter's high-resolution camera for more detailed views of interesting terrain. Volunteers will start with images from the orbiter's Context Camera (CTX), which provides wide views of the Red Planet. The first two images in this series are from CTX; the top right image zooms into a portion of the image at left. The top right image highlights the geological spider features, which are carved into the terrain in the Martian spring when dry ice turns to gas. By identifying unusual features like these, volunteers will help the mission team choose targets for the orbiter's High Resolution Imaging Science Experiment (HiRISE) camera, which can reveal more detail than any other camera ever put into orbit around Mars. The final image is this series (bottom right) shows a HiRISE close-up of one of the spider features. http://photojournal.jpl.nasa.gov/catalog/PIA19823
NASA Technical Reports Server (NTRS)
Hunter, Stanley; deNolfo, G. A.; Barbier, L. M.; Link, J. T.; Son, S.; Floyd, S. R.; Guardala, N.; Skopec, M.; Stark, B.
2008-01-01
The Neutron Imaging Camera (NIC) is based on the Three-dimensional Track Imager (3DTI) technology developed at GSFC for gamma-ray astrophysics applications. The 3-DTI, a large volume time-projection chamber, provides accurate, approximately 0.4 mm resolution, 3-D tracking of charged particles. The incident direction of fast neutrons, En > 0.5 MeV, are reconstructed from the momenta and energies of the proton and triton fragments resulting from (sup 3)He(n,p) (sup 3)H interactions in the 3-DTI volume. The performance of the NIC from laboratory and accelerator tests is presented.
2007-03-01
arc at a substorm pseudo-breakup Sb. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHORS 5d. PROJECT NUMBER K. Yago ,, K. Shiokawa, K. Yumoto...Distribution Unlimited Simultaneous DMSP, all-sky camera, and IMAGE FUV observations of the brightening arc at a substorm pseudo-breakup K. Yago "•. K. Shiokawa...2003; Mende et al., particles, field-aligned currents, and plasma convection as- 2003: Yago et al., 2005: Shiokawa et al., 2005). These sociated with
Calibrating Images from the MINERVA Cameras
NASA Astrophysics Data System (ADS)
Mercedes Colón, Ana
2016-01-01
The MINiature Exoplanet Radial Velocity Array (MINERVA) consists of an array of robotic telescopes located on Mount Hopkins, Arizona with the purpose of performing transit photometry and spectroscopy to find Earth-like planets around Sun-like stars. In order to make photometric observations, it is necessary to perform calibrations on the CCD cameras of the telescopes to take into account possible instrument error on the data. In this project, we developed a pipeline that takes optical images, calibrates them using sky flats, darks, and biases to generate a transit light curve.
The Next Generation Space Telescope
NASA Technical Reports Server (NTRS)
Mather, John C.; Seery, Bernard (Technical Monitor)
2001-01-01
The Next Generation Space Telescope NGST is an 6-7 m class radiatively cooled telescope, planned for launch to the Lagrange point L2 in 2009, to be built by a partnership of NASA, ESA, and CSA. The NGST science program calls for three core instruments: 1) Near IR camera, 0.6 - 5 micrometer; 2) Near IR multiobject spectrometer, 1 - 5 micrometer, and 3) Mid IR camera and spectrometer, 5 - 28 micrometers. I will report on the scientific goals, project status, and the recent reduction in aperture from the target of 8 m.
THE BEAR BROOK WATERSHED MANIPULATION PROJECT: WATERSHED SCIENCE IN A POLICY PERSPECTIVE. (R825762)
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...
Involving Learners in Planning TNO Observations with SALT
NASA Astrophysics Data System (ADS)
Flanagan, C.; de Villiers, G.; Tlaka, C.
2006-03-01
We present a "real science project" at the Johannesburg Planetarium in which learners from less-well-resourced schools helped plan observations at SALT by "observing" home-made "minor planets" using cellphone cameras and photo-software.
DOT National Transportation Integrated Search
2015-01-01
This report documents the findings of the road condition reporting project where the feasibility of live reporting of the road : conditions with an Android camera and computer vision algorithms was tested. An app was developed that can collect videos...
Caltrans bridge inspection aerial robot.
DOT National Transportation Integrated Search
2008-10-01
The California Department of Transportation (Caltrans) project resulted in the development of a twin-motor, : single duct, electric-powered Aerobot designed of carrying video cameras up to 200 feet in elevation to enable : close inspection of bridges...
2017-10-16
Dr. Scott Shipley of Ascentech Enterprises makes an adjustment to the Spectrum unit. He is the project engineer for the effort working under the Engineering Services Contract at NASA's Kennedy Space Center. The device is being built for use aboard the International Space Station and is designed to expose different organisms to different color of fluorescent light while a camera records what's happening with time-laps imagery. Results from the Spectrum project will shed light on which living things are best suited for long-duration flights into deep space.
Mathematical expressions using fringe projections for transparent objects
NASA Astrophysics Data System (ADS)
Su, Wei-Hung; Cheng, Chau-Jern
2017-08-01
A setup using fringe projection techniques to perform 3D profile measurements for transparent objects is presented. The related mathematical equations are derived as well. A fringe pattern is illuminated onto the transparent object. Fringes passing through the inspected object are then projected onto a screen. A CCD camera is employed to record the transmitted fringes on the screen. Fringe on the screen are deformed by the refractive index and the surface structure, and therefore are desirable to describe the shape of the inspected sample.
Panoramic 3D Reconstruction by Fusing Color Intensity and Laser Range Data
NASA Astrophysics Data System (ADS)
Jiang, Wei; Lu, Jian
Technology for capturing panoramic (360 degrees) three-dimensional information in a real environment have many applications in fields: virtual and complex reality, security, robot navigation, and so forth. In this study, we examine an acquisition device constructed of a regular CCD camera and a 2D laser range scanner, along with a technique for panoramic 3D reconstruction using a data fusion algorithm based on an energy minimization framework. The acquisition device can capture two types of data of a panoramic scene without occlusion between two sensors: a dense spatio-temporal volume from a camera and distance information from a laser scanner. We resample the dense spatio-temporal volume for generating a dense multi-perspective panorama that has equal spatial resolution to that of the original images acquired using a regular camera, and also estimate a dense panoramic depth-map corresponding to the generated reference panorama by extracting trajectories from the dense spatio-temporal volume with a selecting camera. Moreover, for determining distance information robustly, we propose a data fusion algorithm that is embedded into an energy minimization framework that incorporates active depth measurements using a 2D laser range scanner and passive geometry reconstruction from an image sequence obtained using the CCD camera. Thereby, measurement precision and robustness can be improved beyond those available by conventional methods using either passive geometry reconstruction (stereo vision) or a laser range scanner. Experimental results using both synthetic and actual images show that our approach can produce high-quality panoramas and perform accurate 3D reconstruction in a panoramic environment.
Best practices to optimize intraoperative photography.
Gaujoux, Sébastien; Ceribelli, Cecilia; Goudard, Geoffrey; Khayat, Antoine; Leconte, Mahaut; Massault, Pierre-Philippe; Balagué, Julie; Dousset, Bertrand
2016-04-01
Intraoperative photography is used extensively for communication, research, or teaching. The objective of the present work was to define, using a standardized methodology and literature review, the best technical conditions for intraoperative photography. Using either a smartphone camera, a bridge camera, or a single-lens reflex (SLR) camera, photographs were taken under various standard conditions by a professional photographer. All images were independently assessed blinded to technical conditions to define the best shooting conditions and methods. For better photographs, an SLR camera with manual settings should be used. Photographs should be centered and taken vertically and orthogonal to the surgical field with a linear scale to avoid error in perspective. The shooting distance should be about 75 cm using an 80-100-mm focal lens. Flash should be avoided and scialytic low-powered light should be used without focus. The operative field should be clean, wet surfaces should be avoided, and metal instruments should be hidden to avoid reflections. For SLR camera, International Organization for Standardization speed should be as low as possible, autofocus area selection mode should be on single point AF, shutter speed should be above 1/100 second, and aperture should be as narrow as possible, above f/8. For smartphone, use high dynamic range setting if available, use of flash, digital filter, effect apps, and digital zoom is not recommended. If a few basic technical rules are known and applied, high-quality photographs can be taken by amateur photographers and fit the standards accepted in clinical practice, academic communication, and publications. Copyright © 2016 Elsevier Inc. All rights reserved.
QUALITY ASSURANCE PROJECT PLANS: A USELESS PAPER EXERCISE OR VALUABLE AID?
Two perspectives on the fundamental question "Are quality assurance project plans (QAPPS) a useless paper exercise or a valuable aid?" will be explored. These perspectives include those of a Branch Chief (i.e., the supervisor/manager) and an active researcher. As a Branch Chief, ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Van Esch, Patrick; Crisanti, Marta; Mutti, Paolo
2015-07-01
A research project is presented in which we aim at counting individual neutrons with CCD-like cameras. We explore theoretically a technique that allows us to use imaging detectors as counting detectors at lower counting rates, and transits smoothly to continuous imaging at higher counting rates. As such, the hope is to combine the good background rejection properties of standard neutron counting detectors with the absence of dead time of integrating neutron imaging cameras as well as their very good spatial resolution. Compared to Xray detection, the essence of thermal neutron detection is the nuclear conversion reaction. The released energies involvedmore » are of the order of a few MeV, while X-ray detection releases energies of the order of the photon energy, which is in the 10 KeV range. Thanks to advances in camera technology which have resulted in increased quantum efficiency, lower noise, as well as increased frame rate up to 100 fps for CMOS-type cameras, this more than 100-fold higher available detection energy implies that the individual neutron detection light signal can be significantly above the noise level, as such allowing for discrimination and individual counting, which is hard to achieve with X-rays. The time scale of CMOS-type cameras doesn't allow one to consider time-of-flight measurements, but kinetic experiments in the 10 ms range are possible. The theory is next confronted to the first experimental results. (authors)« less
Generalized assorted pixel camera: postcapture control of resolution, dynamic range, and spectrum.
Yasuma, Fumihito; Mitsunaga, Tomoo; Iso, Daisuke; Nayar, Shree K
2010-09-01
We propose the concept of a generalized assorted pixel (GAP) camera, which enables the user to capture a single image of a scene and, after the fact, control the tradeoff between spatial resolution, dynamic range and spectral detail. The GAP camera uses a complex array (or mosaic) of color filters. A major problem with using such an array is that the captured image is severely under-sampled for at least some of the filter types. This leads to reconstructed images with strong aliasing. We make four contributions in this paper: 1) we present a comprehensive optimization method to arrive at the spatial and spectral layout of the color filter array of a GAP camera. 2) We develop a novel algorithm for reconstructing the under-sampled channels of the image while minimizing aliasing artifacts. 3) We demonstrate how the user can capture a single image and then control the tradeoff of spatial resolution to generate a variety of images, including monochrome, high dynamic range (HDR) monochrome, RGB, HDR RGB, and multispectral images. 4) Finally, the performance of our GAP camera has been verified using extensive simulations that use multispectral images of real world scenes. A large database of these multispectral images has been made available at http://www1.cs.columbia.edu/CAVE/projects/gap_camera/ for use by the research community.
Jordt, Anne; Zelenka, Claudius; von Deimling, Jens Schneider; Koch, Reinhard; Köser, Kevin
2015-12-05
Several acoustic and optical techniques have been used for characterizing natural and anthropogenic gas leaks (carbon dioxide, methane) from the ocean floor. Here, single-camera based methods for bubble stream observation have become an important tool, as they help estimating flux and bubble sizes under certain assumptions. However, they record only a projection of a bubble into the camera and therefore cannot capture the full 3D shape, which is particularly important for larger, non-spherical bubbles. The unknown distance of the bubble to the camera (making it appear larger or smaller than expected) as well as refraction at the camera interface introduce extra uncertainties. In this article, we introduce our wide baseline stereo-camera deep-sea sensor bubble box that overcomes these limitations, as it observes bubbles from two orthogonal directions using calibrated cameras. Besides the setup and the hardware of the system, we discuss appropriate calibration and the different automated processing steps deblurring, detection, tracking, and 3D fitting that are crucial to arrive at a 3D ellipsoidal shape and rise speed of each bubble. The obtained values for single bubbles can be aggregated into statistical bubble size distributions or fluxes for extrapolation based on diffusion and dissolution models and large scale acoustic surveys. We demonstrate and evaluate the wide baseline stereo measurement model using a controlled test setup with ground truth information.