NASA Astrophysics Data System (ADS)
Tornow, Ralf P.; Milczarek, Aleksandra; Odstrcilik, Jan; Kolar, Radim
2017-07-01
A parallel video ophthalmoscope was developed to acquire short video sequences (25 fps, 250 frames) of both eyes simultaneously with exact synchronization. Video sequences were registered off-line to compensate for eye movements. From registered video sequences dynamic parameters like cardiac cycle induced reflection changes and eye movements can be calculated and compared between eyes.
NASA Astrophysics Data System (ADS)
Walton, James S.; Hodgson, Peter; Hallamasek, Karen; Palmer, Jake
2003-07-01
4DVideo is creating a general purpose capability for capturing and analyzing kinematic data from video sequences in near real-time. The core element of this capability is a software package designed for the PC platform. The software ("4DCapture") is designed to capture and manipulate customized AVI files that can contain a variety of synchronized data streams -- including audio, video, centroid locations -- and signals acquired from more traditional sources (such as accelerometers and strain gauges.) The code includes simultaneous capture or playback of multiple video streams, and linear editing of the images (together with the ancilliary data embedded in the files). Corresponding landmarks seen from two or more views are matched automatically, and photogrammetric algorithms permit multiple landmarks to be tracked in two- and three-dimensions -- with or without lens calibrations. Trajectory data can be processed within the main application or they can be exported to a spreadsheet where they can be processed or passed along to a more sophisticated, stand-alone, data analysis application. Previous attempts to develop such applications for high-speed imaging have been limited in their scope, or by the complexity of the application itself. 4DVideo has devised a friendly ("FlowStack") user interface that assists the end-user to capture and treat image sequences in a natural progression. 4DCapture employs the AVI 2.0 standard and DirectX technology which effectively eliminates the file size limitations found in older applications. In early tests, 4DVideo has streamed three RS-170 video sources to disk for more than an hour without loss of data. At this time, the software can acquire video sequences in three ways: (1) directly, from up to three hard-wired cameras supplying RS-170 (monochrome) signals; (2) directly, from a single camera or video recorder supplying an NTSC (color) signal; and (3) by importing existing video streams in the AVI 1.0 or AVI 2.0 formats. The latter is particularly useful for high-speed applications where the raw images are often captured and stored by the camera before being downloaded. Provision has been made to synchronize data acquired from any combination of these video sources using audio and visual "tags." Additional "front-ends," designed for digital cameras, are anticipated.
Mapping wide row crops with video sequences acquired from a tractor moving at treatment speed.
Sainz-Costa, Nadir; Ribeiro, Angela; Burgos-Artizzu, Xavier P; Guijarro, María; Pajares, Gonzalo
2011-01-01
This paper presents a mapping method for wide row crop fields. The resulting map shows the crop rows and weeds present in the inter-row spacing. Because field videos are acquired with a camera mounted on top of an agricultural vehicle, a method for image sequence stabilization was needed and consequently designed and developed. The proposed stabilization method uses the centers of some crop rows in the image sequence as features to be tracked, which compensates for the lateral movement (sway) of the camera and leaves the pitch unchanged. A region of interest is selected using the tracked features, and an inverse perspective technique transforms the selected region into a bird's-eye view that is centered on the image and that enables map generation. The algorithm developed has been tested on several video sequences of different fields recorded at different times and under different lighting conditions, with good initial results. Indeed, lateral displacements of up to 66% of the inter-row spacing were suppressed through the stabilization process, and crop rows in the resulting maps appear straight.
NASA Astrophysics Data System (ADS)
Zingoni, Andrea; Diani, Marco; Corsini, Giovanni
2016-10-01
We developed an algorithm for automatically detecting small and poorly contrasted (dim) moving objects in real-time, within video sequences acquired through a steady infrared camera. The algorithm is suitable for different situations since it is independent of the background characteristics and of changes in illumination. Unlike other solutions, small objects of any size (up to single-pixel), either hotter or colder than the background, can be successfully detected. The algorithm is based on accurately estimating the background at the pixel level and then rejecting it. A novel approach permits background estimation to be robust to changes in the scene illumination and to noise, and not to be biased by the transit of moving objects. Care was taken in avoiding computationally costly procedures, in order to ensure the real-time performance even using low-cost hardware. The algorithm was tested on a dataset of 12 video sequences acquired in different conditions, providing promising results in terms of detection rate and false alarm rate, independently of background and objects characteristics. In addition, the detection map was produced frame by frame in real-time, using cheap commercial hardware. The algorithm is particularly suitable for applications in the fields of video-surveillance and computer vision. Its reliability and speed permit it to be used also in critical situations, like in search and rescue, defence and disaster monitoring.
Anomaly Detection in Moving-Camera Video Sequences Using Principal Subspace Analysis
Thomaz, Lucas A.; Jardim, Eric; da Silva, Allan F.; ...
2017-10-16
This study presents a family of algorithms based on sparse decompositions that detect anomalies in video sequences obtained from slow moving cameras. These algorithms start by computing the union of subspaces that best represents all the frames from a reference (anomaly free) video as a low-rank projection plus a sparse residue. Then, they perform a low-rank representation of a target (possibly anomalous) video by taking advantage of both the union of subspaces and the sparse residue computed from the reference video. Such algorithms provide good detection results while at the same time obviating the need for previous video synchronization. However,more » this is obtained at the cost of a large computational complexity, which hinders their applicability. Another contribution of this paper approaches this problem by using intrinsic properties of the obtained data representation in order to restrict the search space to the most relevant subspaces, providing computational complexity gains of up to two orders of magnitude. The developed algorithms are shown to cope well with videos acquired in challenging scenarios, as verified by the analysis of 59 videos from the VDAO database that comprises videos with abandoned objects in a cluttered industrial scenario.« less
Anomaly Detection in Moving-Camera Video Sequences Using Principal Subspace Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thomaz, Lucas A.; Jardim, Eric; da Silva, Allan F.
This study presents a family of algorithms based on sparse decompositions that detect anomalies in video sequences obtained from slow moving cameras. These algorithms start by computing the union of subspaces that best represents all the frames from a reference (anomaly free) video as a low-rank projection plus a sparse residue. Then, they perform a low-rank representation of a target (possibly anomalous) video by taking advantage of both the union of subspaces and the sparse residue computed from the reference video. Such algorithms provide good detection results while at the same time obviating the need for previous video synchronization. However,more » this is obtained at the cost of a large computational complexity, which hinders their applicability. Another contribution of this paper approaches this problem by using intrinsic properties of the obtained data representation in order to restrict the search space to the most relevant subspaces, providing computational complexity gains of up to two orders of magnitude. The developed algorithms are shown to cope well with videos acquired in challenging scenarios, as verified by the analysis of 59 videos from the VDAO database that comprises videos with abandoned objects in a cluttered industrial scenario.« less
Peña, Raul; Ávila, Alfonso; Muñoz, David; Lavariega, Juan
2015-01-01
The recognition of clinical manifestations in both video images and physiological-signal waveforms is an important aid to improve the safety and effectiveness in medical care. Physicians can rely on video-waveform (VW) observations to recognize difficult-to-spot signs and symptoms. The VW observations can also reduce the number of false positive incidents and expand the recognition coverage to abnormal health conditions. The synchronization between the video images and the physiological-signal waveforms is fundamental for the successful recognition of the clinical manifestations. The use of conventional equipment to synchronously acquire and display the video-waveform information involves complex tasks such as the video capture/compression, the acquisition/compression of each physiological signal, and the video-waveform synchronization based on timestamps. This paper introduces a data hiding technique capable of both enabling embedding channels and synchronously hiding samples of physiological signals into encoded video sequences. Our data hiding technique offers large data capacity and simplifies the complexity of the video-waveform acquisition and reproduction. The experimental results revealed successful embedding and full restoration of signal's samples. Our results also demonstrated a small distortion in the video objective quality, a small increment in bit-rate, and embedded cost savings of -2.6196% for high and medium motion video sequences.
Heart rate measurement based on face video sequence
NASA Astrophysics Data System (ADS)
Xu, Fang; Zhou, Qin-Wu; Wu, Peng; Chen, Xing; Yang, Xiaofeng; Yan, Hong-jian
2015-03-01
This paper proposes a new non-contact heart rate measurement method based on photoplethysmography (PPG) theory. With this method we can measure heart rate remotely with a camera and ambient light. We collected video sequences of subjects, and detected remote PPG signals through video sequences. Remote PPG signals were analyzed with two methods, Blind Source Separation Technology (BSST) and Cross Spectral Power Technology (CSPT). BSST is a commonly used method, and CSPT is used for the first time in the study of remote PPG signals in this paper. Both of the methods can acquire heart rate, but compared with BSST, CSPT has clearer physical meaning, and the computational complexity of CSPT is lower than that of BSST. Our work shows that heart rates detected by CSPT method have good consistency with the heart rates measured by a finger clip oximeter. With good accuracy and low computational complexity, the CSPT method has a good prospect for the application in the field of home medical devices and mobile health devices.
Tracking Algorithm of Multiple Pedestrians Based on Particle Filters in Video Sequences
Liu, Yun; Wang, Chuanxu; Zhang, Shujun; Cui, Xuehong
2016-01-01
Pedestrian tracking is a critical problem in the field of computer vision. Particle filters have been proven to be very useful in pedestrian tracking for nonlinear and non-Gaussian estimation problems. However, pedestrian tracking in complex environment is still facing many problems due to changes of pedestrian postures and scale, moving background, mutual occlusion, and presence of pedestrian. To surmount these difficulties, this paper presents tracking algorithm of multiple pedestrians based on particle filters in video sequences. The algorithm acquires confidence value of the object and the background through extracting a priori knowledge thus to achieve multipedestrian detection; it adopts color and texture features into particle filter to get better observation results and then automatically adjusts weight value of each feature according to current tracking environment. During the process of tracking, the algorithm processes severe occlusion condition to prevent drift and loss phenomena caused by object occlusion and associates detection results with particle state to propose discriminated method for object disappearance and emergence thus to achieve robust tracking of multiple pedestrians. Experimental verification and analysis in video sequences demonstrate that proposed algorithm improves the tracking performance and has better tracking results. PMID:27847514
What Pace Is Best? Assessing Adults' Learning from Slideshows and Video
ERIC Educational Resources Information Center
Sage, Kara
2014-01-01
When acquiring information from a 2D platform, self-control and/or optimal pacing may help reduce cognitive load and enhance learning outcomes. In the present research, adults viewed novel action sequences via one of four learning media: (1) self-paced slideshows, where viewers advanced through slides at their own pace by clicking a mouse, (2)…
Learning to count begins in infancy: evidence from 18 month olds' visual preferences.
Slaughter, Virginia; Itakura, Shoji; Kutsuki, Aya; Siegal, Michael
2011-10-07
We used a preferential looking paradigm to evaluate infants' preferences for correct versus incorrect counting. Infants viewed a video depicting six fish. In the correct counting sequence, a hand pointed to each fish in turn, accompanied by verbal counting up to six. In the incorrect counting sequence, the hand moved between two of the six fish while there was still verbal counting to six, thereby violating the one-to-one correspondence principle of correct counting. Experiment 1 showed that Australian 18 month olds, but not 15 month olds, significantly preferred to watch the correct counting sequence. In experiment 2, Australian infants' preference for correct counting disappeared when the count words were replaced by beeps or by Japanese count words. In experiment 3, Japanese 18 month olds significantly preferred the correct counting video only when counting was in Japanese. These results show that infants start to acquire the abstract principles governing correct counting prior to producing any counting behaviour.
Learning to count begins in infancy: evidence from 18 month olds' visual preferences
Slaughter, Virginia; Itakura, Shoji; Kutsuki, Aya; Siegal, Michael
2011-01-01
We used a preferential looking paradigm to evaluate infants' preferences for correct versus incorrect counting. Infants viewed a video depicting six fish. In the correct counting sequence, a hand pointed to each fish in turn, accompanied by verbal counting up to six. In the incorrect counting sequence, the hand moved between two of the six fish while there was still verbal counting to six, thereby violating the one-to-one correspondence principle of correct counting. Experiment 1 showed that Australian 18 month olds, but not 15 month olds, significantly preferred to watch the correct counting sequence. In experiment 2, Australian infants' preference for correct counting disappeared when the count words were replaced by beeps or by Japanese count words. In experiment 3, Japanese 18 month olds significantly preferred the correct counting video only when counting was in Japanese. These results show that infants start to acquire the abstract principles governing correct counting prior to producing any counting behaviour. PMID:21325331
Measurement of an Evaporating Drop on a Reflective Substrate
NASA Technical Reports Server (NTRS)
Chao, David F.; Zhang, Nengli
2004-01-01
A figure depicts an apparatus that simultaneously records magnified ordinary top-view video images and laser shadowgraph video images of a sessile drop on a flat, horizontal substrate that can be opaque or translucent and is at least partially specularly reflective. The diameter, contact angle, and rate of evaporation of the drop as functions of time can be calculated from the apparent diameters of the drop in sequences of the images acquired at known time intervals, and the shadowgrams that contain flow patterns indicative of thermocapillary convection (if any) within the drop. These time-dependent parameters and flow patterns are important for understanding the physical processes involved in the spreading and evaporation of drops. The apparatus includes a source of white light and a laser (both omitted from the figure), which are used to form the ordinary image and the shadowgram, respectively. Charge-coupled-device (CCD) camera 1 (with zoom) acquires the ordinary video images, while CCD camera 2 acquires the shadowgrams. With respect to the portion of laser light specularly reflected from the substrate, the drop acts as a plano-convex lens, focusing the laser beam to a shadowgram on the projection screen in front of CCD camera 2. The equations for calculating the diameter, contact angle, and rate of evaporation of the drop are readily derived on the basis of Snell s law of refraction and the geometry of the optics.
Coding visual features extracted from video sequences.
Baroffio, Luca; Cesana, Matteo; Redondi, Alessandro; Tagliasacchi, Marco; Tubaro, Stefano
2014-05-01
Visual features are successfully exploited in several applications (e.g., visual search, object recognition and tracking, etc.) due to their ability to efficiently represent image content. Several visual analysis tasks require features to be transmitted over a bandwidth-limited network, thus calling for coding techniques to reduce the required bit budget, while attaining a target level of efficiency. In this paper, we propose, for the first time, a coding architecture designed for local features (e.g., SIFT, SURF) extracted from video sequences. To achieve high coding efficiency, we exploit both spatial and temporal redundancy by means of intraframe and interframe coding modes. In addition, we propose a coding mode decision based on rate-distortion optimization. The proposed coding scheme can be conveniently adopted to implement the analyze-then-compress (ATC) paradigm in the context of visual sensor networks. That is, sets of visual features are extracted from video frames, encoded at remote nodes, and finally transmitted to a central controller that performs visual analysis. This is in contrast to the traditional compress-then-analyze (CTA) paradigm, in which video sequences acquired at a node are compressed and then sent to a central unit for further processing. In this paper, we compare these coding paradigms using metrics that are routinely adopted to evaluate the suitability of visual features in the context of content-based retrieval, object recognition, and tracking. Experimental results demonstrate that, thanks to the significant coding gains achieved by the proposed coding scheme, ATC outperforms CTA with respect to all evaluation metrics.
Model-Based Analysis of Flow-Mediated Dilation and Intima-Media Thickness
Bartoli, G.; Menegaz, G.; Lisi, M.; Di Stolfo, G.; Dragoni, S.; Gori, T.
2008-01-01
We present an end-to-end system for the automatic measurement of flow-mediated dilation (FMD) and intima-media thickness (IMT) for the assessment of the arterial function. The video sequences are acquired from a B-mode echographic scanner. A spline model (deformable template) is fitted to the data to detect the artery boundaries and track them all along the video sequence. The a priori knowledge about the image features and its content is exploited. Preprocessing is performed to improve both the visual quality of video frames for visual inspection and the performance of the segmentation algorithm without affecting the accuracy of the measurements. The system allows real-time processing as well as a high level of interactivity with the user. This is obtained by a graphical user interface (GUI) enabling the cardiologist to supervise the whole process and to eventually reset the contour extraction at any point in time. The system was validated and the accuracy, reproducibility, and repeatability of the measurements were assessed with extensive in vivo experiments. Jointly with the user friendliness, low cost, and robustness, this makes the system suitable for both research and daily clinical use. PMID:19360110
Using video modeling to teach reciprocal pretend play to children with autism.
MacDonald, Rebecca; Sacramone, Shelly; Mansfield, Renee; Wiltz, Kristine; Ahearn, William H
2009-01-01
The purpose of the present study was to use video modeling to teach children with autism to engage in reciprocal pretend play with typically developing peers. Scripted play scenarios involving various verbalizations and play actions with adults as models were videotaped. Two children with autism were each paired with a typically developing child, and a multiple-probe design across three play sets was used to evaluate the effects of the video modeling procedure. Results indicated that both children with autism and the typically developing peers acquired the sequences of scripted verbalizations and play actions quickly and maintained this performance during follow-up probes. In addition, probes indicated an increase in the mean number of unscripted verbalizations as well as reciprocal verbal interactions and cooperative play. These findings are discussed as they relate to the development of reciprocal pretend-play repertoires in young children with autism.
Using Video Modeling to Teach Reciprocal Pretend Play to Children with Autism
MacDonald, Rebecca; Sacramone, Shelly; Mansfield, Renee; Wiltz, Kristine; Ahearn, William H
2009-01-01
The purpose of the present study was to use video modeling to teach children with autism to engage in reciprocal pretend play with typically developing peers. Scripted play scenarios involving various verbalizations and play actions with adults as models were videotaped. Two children with autism were each paired with a typically developing child, and a multiple-probe design across three play sets was used to evaluate the effects of the video modeling procedure. Results indicated that both children with autism and the typically developing peers acquired the sequences of scripted verbalizations and play actions quickly and maintained this performance during follow-up probes. In addition, probes indicated an increase in the mean number of unscripted verbalizations as well as reciprocal verbal interactions and cooperative play. These findings are discussed as they relate to the development of reciprocal pretend-play repertoires in young children with autism. PMID:19721729
Preliminary study of synthetic aperture tissue harmonic imaging on in-vivo data
NASA Astrophysics Data System (ADS)
Rasmussen, Joachim H.; Hemmsen, Martin C.; Madsen, Signe S.; Hansen, Peter M.; Nielsen, Michael B.; Jensen, Jørgen A.
2013-03-01
A method for synthetic aperture tissue harmonic imaging is investigated. It combines synthetic aperture sequen- tial beamforming (SASB) with tissue harmonic imaging (THI) to produce an increased and more uniform spatial resolution and improved side lobe reduction compared to conventional B-mode imaging. Synthetic aperture sequential beamforming tissue harmonic imaging (SASB-THI) was implemented on a commercially available BK 2202 Pro Focus UltraView ultrasound system and compared to dynamic receive focused tissue harmonic imag- ing (DRF-THI) in clinical scans. The scan sequence that was implemented on the UltraView system acquires both SASB-THI and DRF-THI simultaneously. Twenty-four simultaneously acquired video sequences of in-vivo abdominal SASB-THI and DRF-THI scans on 3 volunteers of 4 different sections of liver and kidney tissues were created. Videos of the in-vivo scans were presented in double blinded studies to two radiologists for image quality performance scoring. Limitations to the systems transmit stage prevented user defined transmit apodization to be applied. Field II simulations showed that side lobes in SASB could be improved by using Hanning transmit apodization. Results from the image quality study show, that in the current configuration on the UltraView system, where no transmit apodization was applied, SASB-THI and DRF-THI produced equally good images. It is expected that given the use of transmit apodization, SASB-THI could be further improved.
NASA Astrophysics Data System (ADS)
Dan, Luo; Ohya, Jun
2010-02-01
Recognizing hand gestures from the video sequence acquired by a dynamic camera could be a useful interface between humans and mobile robots. We develop a state based approach to extract and recognize hand gestures from moving camera images. We improved Human-Following Local Coordinate (HFLC) System, a very simple and stable method for extracting hand motion trajectories, which is obtained from the located human face, body part and hand blob changing factor. Condensation algorithm and PCA-based algorithm was performed to recognize extracted hand trajectories. In last research, this Condensation Algorithm based method only applied for one person's hand gestures. In this paper, we propose a principal component analysis (PCA) based approach to improve the recognition accuracy. For further improvement, temporal changes in the observed hand area changing factor are utilized as new image features to be stored in the database after being analyzed by PCA. Every hand gesture trajectory in the database is classified into either one hand gesture categories, two hand gesture categories, or temporal changes in hand blob changes. We demonstrate the effectiveness of the proposed method by conducting experiments on 45 kinds of sign language based Japanese and American Sign Language gestures obtained from 5 people. Our experimental recognition results show better performance is obtained by PCA based approach than the Condensation algorithm based method.
Dynamic visual attention: motion direction versus motion magnitude
NASA Astrophysics Data System (ADS)
Bur, A.; Wurtz, P.; Müri, R. M.; Hügli, H.
2008-02-01
Defined as an attentive process in the context of visual sequences, dynamic visual attention refers to the selection of the most informative parts of video sequence. This paper investigates the contribution of motion in dynamic visual attention, and specifically compares computer models designed with the motion component expressed either as the speed magnitude or as the speed vector. Several computer models, including static features (color, intensity and orientation) and motion features (magnitude and vector) are considered. Qualitative and quantitative evaluations are performed by comparing the computer model output with human saliency maps obtained experimentally from eye movement recordings. The model suitability is evaluated in various situations (synthetic and real sequences, acquired with fixed and moving camera perspective), showing advantages and inconveniences of each method as well as preferred domain of application.
Wavelet Fusion for Concealed Object Detection Using Passive Millimeter Wave Sequence Images
NASA Astrophysics Data System (ADS)
Chen, Y.; Pang, L.; Liu, H.; Xu, X.
2018-04-01
PMMW imaging system can create interpretable imagery on the objects concealed under clothing, which gives the great advantage to the security check system. Paper addresses wavelet fusion to detect concealed objects using passive millimeter wave (PMMW) sequence images. According to PMMW real-time imager acquired image characteristics and storage methods firstly, using the sum of squared difference (SSD) as the image-related parameters to screen the sequence images. Secondly, the selected images are optimized using wavelet fusion algorithm. Finally, the concealed objects are detected by mean filter, threshold segmentation and edge detection. The experimental results show that this method improves the detection effect of concealed objects by selecting the most relevant images from PMMW sequence images and using wavelet fusion to enhance the information of the concealed objects. The method can be effectively applied to human body concealed object detection in millimeter wave video.
NASA Astrophysics Data System (ADS)
Saur, Günter; Krüger, Wolfgang
2016-06-01
Change detection is an important task when using unmanned aerial vehicles (UAV) for video surveillance. We address changes of short time scale using observations in time distances of a few hours. Each observation (previous and current) is a short video sequence acquired by UAV in near-Nadir view. Relevant changes are, e.g., recently parked or moved vehicles. Examples for non-relevant changes are parallaxes caused by 3D structures of the scene, shadow and illumination changes, and compression or transmission artifacts. In this paper we present (1) a new feature based approach to change detection, (2) a combination with extended image differencing (Saur et al., 2014), and (3) the application to video sequences using temporal filtering. In the feature based approach, information about local image features, e.g., corners, is extracted in both images. The label "new object" is generated at image points, where features occur in the current image and no or weaker features are present in the previous image. The label "vanished object" corresponds to missing or weaker features in the current image and present features in the previous image. This leads to two "directed" change masks and differs from image differencing where only one "undirected" change mask is extracted which combines both label types to the single label "changed object". The combination of both algorithms is performed by merging the change masks of both approaches. A color mask showing the different contributions is used for visual inspection by a human image interpreter.
Real-Time Digital Bright Field Technology for Rapid Antibiotic Susceptibility Testing.
Canali, Chiara; Spillum, Erik; Valvik, Martin; Agersnap, Niels; Olesen, Tom
2018-01-01
Optical scanning through bacterial samples and image-based analysis may provide a robust method for bacterial identification, fast estimation of growth rates and their modulation due to the presence of antimicrobial agents. Here, we describe an automated digital, time-lapse, bright field imaging system (oCelloScope, BioSense Solutions ApS, Farum, Denmark) for rapid and higher throughput antibiotic susceptibility testing (AST) of up to 96 bacteria-antibiotic combinations at a time. The imaging system consists of a digital camera, an illumination unit and a lens where the optical axis is tilted 6.25° relative to the horizontal plane of the stage. Such tilting grants more freedom of operation at both high and low concentrations of microorganisms. When considering a bacterial suspension in a microwell, the oCelloScope acquires a sequence of 6.25°-tilted images to form an image Z-stack. The stack contains the best-focus image, as well as the adjacent out-of-focus images (which contain progressively more out-of-focus bacteria, the further the distance from the best-focus position). The acquisition process is repeated over time, so that the time-lapse sequence of best-focus images is used to generate a video. The setting of the experiment, image analysis and generation of time-lapse videos can be performed through a dedicated software (UniExplorer, BioSense Solutions ApS). The acquired images can be processed for online and offline quantification of several morphological parameters, microbial growth, and inhibition over time.
NASA Astrophysics Data System (ADS)
Stovall, Stephanie; Midgett, Madeline; Thornburg, Kent; Rugonyi, Sandra
2016-11-01
Abnormal blood flow during early cardiovascular development has been identified as a key factor in the pathogenesis of congenital heart disease; however, the mechanisms by which altered hemodynamics induce cardiac malformations are poorly understood. This study used outflow tract (OFT) banding to model increased afterload, pressure, and blood flow velocities at tubular stages of heart development and characterized the immediate changes in cardiac wall motion due to banding in chicken embryo models with light microscopy-based video densitometry. Optical videos were used to acquire two-dimensional heart image sequences over the cardiac cycle, from which intensity data were extracted along the heart centerline at several locations in the heart ventricle and OFT. While no changes were observed in the synchronous contraction of the ventricle with banding, the peristaltic-like wall motion in the OFT was significantly affected. Our data provide valuable insight into early cardiac biomechanics and its characterization using a simple light microscopy-based imaging modality.
ESTABLISHING VERBAL REPERTOIRES IN CHILDREN WITH AUTISM USING FUNCTION-BASED VIDEO MODELING
Plavnick, Joshua B; Ferreri, Summer J
2011-01-01
Previous research suggests that language-training procedures for children with autism might be enhanced following an assessment of conditions that evoke emerging verbal behavior. The present investigation examined a methodology to teach recognizable mands based on environmental variables known to evoke participants' idiosyncratic communicative responses in the natural environment. An alternating treatments design was used during Experiment 1 to identify the variables that were functionally related to gestures emitted by 4 children with autism. Results showed that gestures functioned as requests for attention for 1 participant and as requests for assistance to obtain a preferred item or event for 3 participants. Video modeling was used during Experiment 2 to compare mand acquisition when video sequences were either related or unrelated to the results of the functional analysis. An alternating treatments within multiple probe design showed that participants repeatedly acquired mands during the function-based condition but not during the nonfunction-based condition. In addition, generalization of the response was observed during the former but not the latter condition. PMID:22219527
Evaluation of a HDR image sensor with logarithmic response for mobile video-based applications
NASA Astrophysics Data System (ADS)
Tektonidis, Marco; Pietrzak, Mateusz; Monnin, David
2017-10-01
The performance of mobile video-based applications using conventional LDR (Low Dynamic Range) image sensors highly depends on the illumination conditions. As an alternative, HDR (High Dynamic Range) image sensors with logarithmic response are capable to acquire illumination-invariant HDR images in a single shot. We have implemented a complete image processing framework for a HDR sensor, including preprocessing methods (nonuniformity correction (NUC), cross-talk correction (CTC), and demosaicing) as well as tone mapping (TM). We have evaluated the HDR sensor for video-based applications w.r.t. the display of images and w.r.t. image analysis techniques. Regarding the display we have investigated the image intensity statistics over time, and regarding image analysis we assessed the number of feature correspondences between consecutive frames of temporal image sequences. For the evaluation we used HDR image data recorded from a vehicle on outdoor or combined outdoor/indoor itineraries, and we performed a comparison with corresponding conventional LDR image data.
Establishing verbal repertoires in children with autism using function-based video modeling.
Plavnick, Joshua B; Ferreri, Summer J
2011-01-01
Previous research suggests that language-training procedures for children with autism might be enhanced following an assessment of conditions that evoke emerging verbal behavior. The present investigation examined a methodology to teach recognizable mands based on environmental variables known to evoke participants' idiosyncratic communicative responses in the natural environment. An alternating treatments design was used during Experiment 1 to identify the variables that were functionally related to gestures emitted by 4 children with autism. Results showed that gestures functioned as requests for attention for 1 participant and as requests for assistance to obtain a preferred item or event for 3 participants. Video modeling was used during Experiment 2 to compare mand acquisition when video sequences were either related or unrelated to the results of the functional analysis. An alternating treatments within multiple probe design showed that participants repeatedly acquired mands during the function-based condition but not during the nonfunction-based condition. In addition, generalization of the response was observed during the former but not the latter condition.
Video Image Stabilization and Registration
NASA Technical Reports Server (NTRS)
Hathaway, David H. (Inventor); Meyer, Paul J. (Inventor)
2002-01-01
A method of stabilizing and registering a video image in multiple video fields of a video sequence provides accurate determination of the image change in magnification, rotation and translation between video fields, so that the video fields may be accurately corrected for these changes in the image in the video sequence. In a described embodiment, a key area of a key video field is selected which contains an image which it is desired to stabilize in a video sequence. The key area is subdivided into nested pixel blocks and the translation of each of the pixel blocks from the key video field to a new video field is determined as a precursor to determining change in magnification, rotation and translation of the image from the key video field to the new video field.
Video Image Stabilization and Registration
NASA Technical Reports Server (NTRS)
Hathaway, David H. (Inventor); Meyer, Paul J. (Inventor)
2003-01-01
A method of stabilizing and registering a video image in multiple video fields of a video sequence provides accurate determination of the image change in magnification, rotation and translation between video fields, so that the video fields may be accurately corrected for these changes in the image in the video sequence. In a described embodiment, a key area of a key video field is selected which contains an image which it is desired to stabilize in a video sequence. The key area is subdivided into nested pixel blocks and the translation of each of the pixel blocks from the key video field to a new video field is determined as a precursor to determining change in magnification, rotation and translation of the image from the key video field to the new video field.
NASA Astrophysics Data System (ADS)
Wade, P.; Courtney, A.
2010-12-01
Students enrolled in an undergraduate non-science majors’ Energy Perspectives course created 10-15 minute video documentaries on topics related to Energy Resources and the Environment. Video project topics included wave, biodiesel, clean coal, hydro, solar and “off-the-grid” energy technologies. No student had any prior experience with creating video projects. Students had Liberal Arts academic backgrounds that included Anthropology, Theater Arts, International Studies, English and Early Childhood Education. Students were required to: 1) select a topic, 2) conduct research, 3) write a narrative, 4) construct a project storyboard, 5) shoot or acquire video and photos (from legal sources), 6) record the narrative, and 7) construct the video documentary. This study describes the instructional approach of using student created video documentaries as projects in an undergraduate non-science majors’ science course. Two knowledge survey instruments were used for assessment purposes. Each instrument was administered Pre-, Mid- and Post course. One survey focused on the skills necessary to research and produce video documentaries. Results showed students acquired enhanced technology skills especially with regard to research techniques, writing skills and video editing. The second survey assessed students’ content knowledge acquired from each documentary. Results indicated students’ increased their content knowledge of energy resource topics. Students reported very favorable evaluations concerning their experience with creating “Ken Burns” video project documentaries.
Real-time moving objects detection and tracking from airborne infrared camera
NASA Astrophysics Data System (ADS)
Zingoni, Andrea; Diani, Marco; Corsini, Giovanni
2017-10-01
Detecting and tracking moving objects in real-time from an airborne infrared (IR) camera offers interesting possibilities in video surveillance, remote sensing and computer vision applications, such as monitoring large areas simultaneously, quickly changing the point of view on the scene and pursuing objects of interest. To fully exploit such a potential, versatile solutions are needed, but, in the literature, the majority of them works only under specific conditions about the considered scenario, the characteristics of the moving objects or the aircraft movements. In order to overcome these limitations, we propose a novel approach to the problem, based on the use of a cheap inertial navigation system (INS), mounted on the aircraft. To exploit jointly the information contained in the acquired video sequence and the data provided by the INS, a specific detection and tracking algorithm has been developed. It consists of three main stages performed iteratively on each acquired frame. The detection stage, in which a coarse detection map is computed, using a local statistic both fast to calculate and robust to noise and self-deletion of the targeted objects. The registration stage, in which the position of the detected objects is coherently reported on a common reference frame, by exploiting the INS data. The tracking stage, in which the steady objects are rejected, the moving objects are tracked, and an estimation of their future position is computed, to be used in the subsequent iteration. The algorithm has been tested on a large dataset of simulated IR video sequences, recreating different environments and different movements of the aircraft. Promising results have been obtained, both in terms of detection and false alarm rate, and in terms of accuracy in the estimation of position and velocity of the objects. In addition, for each frame, the detection and tracking map has been generated by the algorithm, before the acquisition of the subsequent frame, proving its capability to work in real-time.
NASA Technical Reports Server (NTRS)
Kasturi, Rangachar; Devadiga, Sadashiva; Tang, Yuan-Liang
1994-01-01
This research was initiated as a part of the Advanced Sensor and Imaging System Technology (ASSIST) program at NASA Langley Research Center. The primary goal of this research is the development of image analysis algorithms for the detection of runways and other objects using an on-board camera. Initial effort was concentrated on images acquired using a passive millimeter wave (PMMW) sensor. The images obtained using PMMW sensors under poor visibility conditions due to atmospheric fog are characterized by very low spatial resolution but good image contrast compared to those images obtained using sensors operating in the visible spectrum. Algorithms developed for analyzing these images using a model of the runway and other objects are described in Part 1 of this report. Experimental verification of these algorithms was limited to a sequence of images simulated from a single frame of PMMW image. Subsequent development and evaluation of algorithms was done using video image sequences. These images have better spatial and temporal resolution compared to PMMW images. Algorithms for reliable recognition of runways and accurate estimation of spatial position of stationary objects on the ground have been developed and evaluated using several image sequences. These algorithms are described in Part 2 of this report. A list of all publications resulting from this work is also included.
Computer-aided system for detecting runway incursions
NASA Astrophysics Data System (ADS)
Sridhar, Banavar; Chatterji, Gano B.
1994-07-01
A synthetic vision system for enhancing the pilot's ability to navigate and control the aircraft on the ground is described. The system uses the onboard airport database and images acquired by external sensors. Additional navigation information needed by the system is provided by the Inertial Navigation System and the Global Positioning System. The various functions of the system, such as image enhancement, map generation, obstacle detection, collision avoidance, guidance, etc., are identified. The available technologies, some of which were developed at NASA, that are applicable to the aircraft ground navigation problem are noted. Example images of a truck crossing the runway while the aircraft flies close to the runway centerline are described. These images are from a sequence of images acquired during one of the several flight experiments conducted by NASA to acquire data to be used for the development and verification of the synthetic vision concepts. These experiments provide a realistic database including video and infrared images, motion states from the Inertial Navigation System and the Global Positioning System, and camera parameters.
Evolving discriminators for querying video sequences
NASA Astrophysics Data System (ADS)
Iyengar, Giridharan; Lippman, Andrew B.
1997-01-01
In this paper we present a framework for content based query and retrieval of information from large video databases. This framework enables content based retrieval of video sequences by characterizing the sequences using motion, texture and colorimetry cues. This characterization is biologically inspired and results in a compact parameter space where every segment of video is represented by an 8 dimensional vector. Searching and retrieval is done in real- time with accuracy in this parameter space. Using this characterization, we then evolve a set of discriminators using Genetic Programming Experiments indicate that these discriminators are capable of analyzing and characterizing video. The VideoBook is able to search and retrieve video sequences with 92% accuracy in real-time. Experiments thus demonstrate that the characterization is capable of extracting higher level structure from raw pixel values.
Video monitoring of oxygen saturation during controlled episodes of acute hypoxia.
Addison, Paul S; Foo, David M H; Jacquel, Dominique; Borg, Ulf
2016-08-01
A method for extracting video photoplethysmographic information from an RGB video stream is tested on data acquired during a porcine model of acute hypoxia. Cardiac pulsatile information was extracted from the acquired signals and processed to determine a continuously reported oxygen saturation (SvidO2). A high degree of correlation was found to exist between the video and a reference from a pulse oximeter. The calculated mean bias and accuracy across all eight desaturation episodes were -0.03% (range: -0.21% to 0.24%) and accuracy 4.90% (range: 3.80% to 6.19%) respectively. The results support the hypothesis that oxygen saturation trending can be evaluated accurately from a video system during acute hypoxia.
Yang, Yang; Stanković, Vladimir; Xiong, Zixiang; Zhao, Wei
2009-03-01
Following recent works on the rate region of the quadratic Gaussian two-terminal source coding problem and limit-approaching code designs, this paper examines multiterminal source coding of two correlated, i.e., stereo, video sequences to save the sum rate over independent coding of both sequences. Two multiterminal video coding schemes are proposed. In the first scheme, the left sequence of the stereo pair is coded by H.264/AVC and used at the joint decoder to facilitate Wyner-Ziv coding of the right video sequence. The first I-frame of the right sequence is successively coded by H.264/AVC Intracoding and Wyner-Ziv coding. An efficient stereo matching algorithm based on loopy belief propagation is then adopted at the decoder to produce pixel-level disparity maps between the corresponding frames of the two decoded video sequences on the fly. Based on the disparity maps, side information for both motion vectors and motion-compensated residual frames of the right sequence are generated at the decoder before Wyner-Ziv encoding. In the second scheme, source splitting is employed on top of classic and Wyner-Ziv coding for compression of both I-frames to allow flexible rate allocation between the two sequences. Experiments with both schemes on stereo video sequences using H.264/AVC, LDPC codes for Slepian-Wolf coding of the motion vectors, and scalar quantization in conjunction with LDPC codes for Wyner-Ziv coding of the residual coefficients give a slightly lower sum rate than separate H.264/AVC coding of both sequences at the same video quality.
Real-Time Acquisition and Display of Data and Video
NASA Technical Reports Server (NTRS)
Bachnak, Rafic; Chakinarapu, Ramya; Garcia, Mario; Kar, Dulal; Nguyen, Tien
2007-01-01
This paper describes the development of a prototype that takes in an analog National Television System Committee (NTSC) video signal generated by a video camera and data acquired by a microcontroller and display them in real-time on a digital panel. An 8051 microcontroller is used to acquire power dissipation by the display panel, room temperature, and camera zoom level. The paper describes the major hardware components and shows how they are interfaced into a functional prototype. Test data results are presented and discussed.
ERIC Educational Resources Information Center
Levac, Danielle; Miller, Patricia; Missiuna, Cheryl
2012-01-01
Little is known about how therapists promote learning of functional motor skills for children with acquired brain injuries. This study explores physiotherapists' description of these interventions in comparison to virtual reality (VR) video game-based therapy. Six physiotherapists employed at a children's rehabilitation center participated in…
Use of Internet Resources in the Biology Lecture Classroom.
ERIC Educational Resources Information Center
Francis, Joseph W.
2000-01-01
Introduces internet resources that are available for instructional use in biology classrooms. Provides information on video-based technologies to create and capture video sequences, interactive web sites that allow interaction with biology simulations, online texts, and interactive videos that display animated video sequences. (YDS)
Sequence to Sequence - Video to Text
2015-12-11
Saenko, and S. Guadarrama. Generating natural-language video descriptions using text - mined knowledge. In AAAI, July 2013. 2 [20] P. Kuznetsova, V...Sequence to Sequence – Video to Text Subhashini Venugopalan1 Marcus Rohrbach2,4 Jeff Donahue2 Raymond Mooney1 Trevor Darrell2 Kate Saenko3...1. Introduction Describing visual content with natural language text has recently received increased interest, especially describing images with a
NASA Astrophysics Data System (ADS)
Lee, Feifei; Kotani, Koji; Chen, Qiu; Ohmi, Tadahiro
2010-02-01
In this paper, a fast search algorithm for MPEG-4 video clips from video database is proposed. An adjacent pixel intensity difference quantization (APIDQ) histogram is utilized as the feature vector of VOP (video object plane), which had been reliably applied to human face recognition previously. Instead of fully decompressed video sequence, partially decoded data, namely DC sequence of the video object are extracted from the video sequence. Combined with active search, a temporal pruning algorithm, fast and robust video search can be realized. The proposed search algorithm has been evaluated by total 15 hours of video contained of TV programs such as drama, talk, news, etc. to search for given 200 MPEG-4 video clips which each length is 15 seconds. Experimental results show the proposed algorithm can detect the similar video clip in merely 80ms, and Equal Error Rate (ERR) of 2 % in drama and news categories are achieved, which are more accurately and robust than conventional fast video search algorithm.
OceanVideoLab: A Tool for Exploring Underwater Video
NASA Astrophysics Data System (ADS)
Ferrini, V. L.; Morton, J. J.; Wiener, C.
2016-02-01
Video imagery acquired with underwater vehicles is an essential tool for characterizing seafloor ecosystems and seafloor geology. It is a fundamental component of ocean exploration that facilitates real-time operations, augments multidisciplinary scientific research, and holds tremendous potential for public outreach and engagement. Acquiring, documenting, managing, preserving and providing access to large volumes of video acquired with underwater vehicles presents a variety of data stewardship challenges to the oceanographic community. As a result, only a fraction of underwater video content collected with research submersibles is documented, discoverable and/or viewable online. With more than 1 billion users, YouTube offers infrastructure that can be leveraged to help address some of the challenges associated with sharing underwater video with a broad global audience. Anyone can post content to YouTube, and some oceanographic organizations, such as the Schmidt Ocean Institute, have begun live-streaming video directly from underwater vehicles. OceanVideoLab (oceanvideolab.org) was developed to help improve access to underwater video through simple annotation, browse functionality, and integration with related environmental data. Any underwater video that is publicly accessible on YouTube can be registered with OceanVideoLab by simply providing a URL. It is strongly recommended that a navigational file also be supplied to enable geo-referencing of observations. Once a video is registered, it can be viewed and annotated using a simple user interface that integrates observations with vehicle navigation data if provided. This interface includes an interactive map and a list of previous annotations that allows users to jump to times of specific observations in the video. Future enhancements to OceanVideoLab will include the deployment of a search interface, the development of an application program interface (API) that will drive the search and enable querying of content by other systems/tools, the integration of related environmental data from complementary data systems (e.g. temperature, bathymetry), and the expansion of infrastructure to enable broad crowdsourcing of annotations.
Extended image differencing for change detection in UAV video mosaics
NASA Astrophysics Data System (ADS)
Saur, Günter; Krüger, Wolfgang; Schumann, Arne
2014-03-01
Change detection is one of the most important tasks when using unmanned aerial vehicles (UAV) for video reconnaissance and surveillance. We address changes of short time scale, i.e. the observations are taken in time distances from several minutes up to a few hours. Each observation is a short video sequence acquired by the UAV in near-nadir view and the relevant changes are, e.g., recently parked or moved vehicles. In this paper we extend our previous approach of image differencing for single video frames to video mosaics. A precise image-to-image registration combined with a robust matching approach is needed to stitch the video frames to a mosaic. Additionally, this matching algorithm is applied to mosaic pairs in order to align them to a common geometry. The resulting registered video mosaic pairs are the input of the change detection procedure based on extended image differencing. A change mask is generated by an adaptive threshold applied to a linear combination of difference images of intensity and gradient magnitude. The change detection algorithm has to distinguish between relevant and non-relevant changes. Examples for non-relevant changes are stereo disparity at 3D structures of the scene, changed size of shadows, and compression or transmission artifacts. The special effects of video mosaicking such as geometric distortions and artifacts at moving objects have to be considered, too. In our experiments we analyze the influence of these effects on the change detection results by considering several scenes. The results show that for video mosaics this task is more difficult than for single video frames. Therefore, we extended the image registration by estimating an elastic transformation using a thin plate spline approach. The results for mosaics are comparable to that of single video frames and are useful for interactive image exploitation due to a larger scene coverage.
Real-time UAV trajectory generation using feature points matching between video image sequences
NASA Astrophysics Data System (ADS)
Byun, Younggi; Song, Jeongheon; Han, Dongyeob
2017-09-01
Unmanned aerial vehicles (UAVs), equipped with navigation systems and video capability, are currently being deployed for intelligence, reconnaissance and surveillance mission. In this paper, we present a systematic approach for the generation of UAV trajectory using a video image matching system based on SURF (Speeded up Robust Feature) and Preemptive RANSAC (Random Sample Consensus). Video image matching to find matching points is one of the most important steps for the accurate generation of UAV trajectory (sequence of poses in 3D space). We used the SURF algorithm to find the matching points between video image sequences, and removed mismatching by using the Preemptive RANSAC which divides all matching points to outliers and inliers. The inliers are only used to determine the epipolar geometry for estimating the relative pose (rotation and translation) between image sequences. Experimental results from simulated video image sequences showed that our approach has a good potential to be applied to the automatic geo-localization of the UAVs system
26 CFR 1.181-3 - Qualified film or television production.
Code of Federal Regulations, 2012 CFR
2012-04-01
... any motion picture film or video tape (including digital video) production the production costs of... person acquires a completed motion picture film or video tape (including digital video) that the seller... include property for which records are required to be maintained under 18 U.S.C. 2257. (c) Compensation...
26 CFR 1.181-3 - Qualified film or television production.
Code of Federal Regulations, 2014 CFR
2014-04-01
... any motion picture film or video tape (including digital video) production the production costs of... person acquires a completed motion picture film or video tape (including digital video) that the seller... include property for which records are required to be maintained under 18 U.S.C. 2257. (c) Compensation...
26 CFR 1.181-3 - Qualified film or television production.
Code of Federal Regulations, 2013 CFR
2013-04-01
... any motion picture film or video tape (including digital video) production the production costs of... person acquires a completed motion picture film or video tape (including digital video) that the seller... include property for which records are required to be maintained under 18 U.S.C. 2257. (c) Compensation...
2005-01-01
Sequencing of the human genome has ushered in a new era of biology. The technologies developed to facilitate the sequencing of the human genome are now being applied to the sequencing of other genomes. In 2004, a partnership was formed between Washington University School of Medicine Genome Sequencing Center's Outreach Program and Washington University Department of Biology Science Outreach to create a video tour depicting the processes involved in large-scale sequencing. “Sequencing a Genome: Inside the Washington University Genome Sequencing Center” is a tour of the laboratory that follows the steps in the sequencing pipeline, interspersed with animated explanations of the scientific procedures used at the facility. Accompanying interviews with the staff illustrate different entry levels for a career in genome science. This video project serves as an example of how research and academic institutions can provide teachers and students with access and exposure to innovative technologies at the forefront of biomedical research. Initial feedback on the video from undergraduate students, high school teachers, and high school students provides suggestions for use of this video in a classroom setting to supplement present curricula. PMID:16341256
Comparing light sensitivity, linearity and step response of electronic cameras for ophthalmology.
Kopp, O; Markert, S; Tornow, R P
2002-01-01
To develop and test a procedure to measure and compare light sensitivity, linearity and step response of electronic cameras. The pixel value (PV) of digitized images as a function of light intensity (I) was measured. The sensitivity was calculated from the slope of the P(I) function, the linearity was estimated from the correlation coefficient of this function. To measure the step response, a short sequence of images was acquired. During acquisition, a light source was switched on and off using a fast shutter. The resulting PV was calculated for each video field of the sequence. A CCD camera optimized for the near-infrared (IR) spectrum showed the highest sensitivity for both, visible and IR light. There are little differences in linearity. The step response depends on the procedure of integration and read out.
NASA Astrophysics Data System (ADS)
Lee, Seungwon; Park, Ilkwon; Kim, Manbae; Byun, Hyeran
2006-10-01
As digital broadcasting technologies have been rapidly progressed, users' expectations for realistic and interactive broadcasting services also have been increased. As one of such services, 3D multi-view broadcasting has received much attention recently. In general, all the view sequences acquired at the server are transmitted to the client. Then, the user can select a part of views or all the views according to display capabilities. However, this kind of system requires high processing power of the server as well as the client, thus posing a difficulty in practical applications. To overcome this problem, a relatively simple method is to transmit only two view-sequences requested by the client in order to deliver a stereoscopic video. In this system, effective communication between the server and the client is one of important aspects. In this paper, we propose an efficient multi-view system that transmits two view-sequences and their depth maps according to user's request. The view selection process is integrated into MPEG-21 DIA (Digital Item Adaptation) so that our system is compatible to MPEG-21 multimedia framework. DIA is generally composed of resource adaptation and descriptor adaptation. It is one of merits that SVA (stereoscopic video adaptation) descriptors defined in DIA standard are used to deliver users' preferences and device capabilities. Furthermore, multi-view descriptions related to multi-view camera and system are newly introduced. The syntax of the descriptions and their elements is represented in XML (eXtensible Markup Language) schema. If the client requests an adapted descriptor (e.g., view numbers) to the server, then the server sends its associated view sequences. Finally, we present a method which can reduce user's visual discomfort that might occur while viewing stereoscopic video. This phenomenon happens when view changes as well as when a stereoscopic image produces excessive disparity caused by a large baseline between two cameras. To solve for the former, IVR (intermediate view reconstruction) is employed for smooth transition between two stereoscopic view sequences. As well, a disparity adjustment scheme is used for the latter. Finally, from the implementation of testbed and the experiments, we can show the valuables and possibilities of our system.
Problematic topic transitions in dysarthric conversation.
Bloch, Steven; Saldert, Charlotta; Ferm, Ulrika
2015-01-01
This study examined the nature of topic transition problems associated with acquired progressive dysarthric speech in the everyday conversation of people with motor neurone disease. Using conversation analytic methods, a video collection of five naturally occurring problematic topic transitions was identified, transcribed and analysed. These were extracted from a main collection of over 200 other-initiated repair sequences and a sub-set of 15 problematic topic transition sequences. The sequences were analysed with reference to how the participants both identified and resolved the problems. Analysis revealed that topic transition by people with dysarthria can prove problematic. Conversation partners may find transitions problematic not only because of speech intelligibility but also because of a sequential disjuncture between the dysarthric speech turn and whatever topic has come prior. In addition the treatment of problematic topic transition as a complaint reveals the potential vulnerability of people with dysarthria to judgements of competence. These findings have implications for how dysarthria is conceptualized and how specific actions in conversation, such as topic transition, might be suitable targets for clinical intervention.
(abstract) Synthesis of Speaker Facial Movements to Match Selected Speech Sequences
NASA Technical Reports Server (NTRS)
Scott, Kenneth C.
1994-01-01
We are developing a system for synthesizing image sequences the simulate the facial motion of a speaker. To perform this synthesis, we are pursuing two major areas of effort. We are developing the necessary computer graphics technology to synthesize a realistic image sequence of a person speaking selected speech sequences. Next, we are developing a model that expresses the relation between spoken phonemes and face/mouth shape. A subject is video taped speaking an arbitrary text that contains expression of the full list of desired database phonemes. The subject is video taped from the front speaking normally, recording both audio and video detail simultaneously. Using the audio track, we identify the specific video frames on the tape relating to each spoken phoneme. From this range we digitize the video frame which represents the extreme of mouth motion/shape. Thus, we construct a database of images of face/mouth shape related to spoken phonemes. A selected audio speech sequence is recorded which is the basis for synthesizing a matching video sequence; the speaker need not be the same as used for constructing the database. The audio sequence is analyzed to determine the spoken phoneme sequence and the relative timing of the enunciation of those phonemes. Synthesizing an image sequence corresponding to the spoken phoneme sequence is accomplished using a graphics technique known as morphing. Image sequence keyframes necessary for this processing are based on the spoken phoneme sequence and timing. We have been successful in synthesizing the facial motion of a native English speaker for a small set of arbitrary speech segments. Our future work will focus on advancement of the face shape/phoneme model and independent control of facial features.
Zelinková, Jana; Shaw, Daniel J; Mareček, Radek; Mikl, Michal; Urbánek, Tomáš; Havlíčková, Darina; Zámečník, Petr; Haitová, Petra; Brázdil, Milan
2014-08-12
Acting appropriately within social contexts requires an ability to appreciate others' mental and emotional states. Indeed, some campaign programs designed to reduce anti-social behaviour seek to elicit empathy for the victims. The effectiveness of these campaigns can be evaluated according to the degree to which they induce such responses, but by applying neuroscientific techniques this can be done at the behavioural and neurophysiological level. Neuroimaging studies aimed at identifying the neural mechanisms behind such socio-cognitive and -emotional processes frequently reveal the role of the superior temporal sulcus (STS). We applied this knowledge to assess the effectiveness of traffic-awareness campaign adverts to induce empathic expression. Functional magnetic resonance imaging (fMRI) data were acquired from 20 healthy male volunteers as they watched these campaign videos consisting of a dramatic sequence of events and catastrophic endings, and control videos without such dramatic endings. Among other structures, a significantly greater neural response was observed within bilateral STS, particularly within the right hemisphere, during the observation of campaign relative to control videos. Furthermore, activation in these brain regions correlated with the subjects' empathic expression. Our results develop our understanding of the role of STS in social cognition. Moreover, our data demonstrate the utility of neuroscientific methods when evaluating the effectiveness of campaign videos in terms of their ability to elicit empathic responses. Our study also demonstrates the utility of these specific stimuli for future neuroscientific research.
2014-01-01
Acting appropriately within social contexts requires an ability to appreciate others’ mental and emotional states. Indeed, some campaign programs designed to reduce anti-social behaviour seek to elicit empathy for the victims. The effectiveness of these campaigns can be evaluated according to the degree to which they induce such responses, but by applying neuroscientific techniques this can be done at the behavioural and neurophysiological level. Neuroimaging studies aimed at identifying the neural mechanisms behind such socio-cognitive and -emotional processes frequently reveal the role of the superior temporal sulcus (STS). We applied this knowledge to assess the effectiveness of traffic-awareness campaign adverts to induce empathic expression. Functional magnetic resonance imaging (fMRI) data were acquired from 20 healthy male volunteers as they watched these campaign videos consisting of a dramatic sequence of events and catastrophic endings, and control videos without such dramatic endings. Among other structures, a significantly greater neural response was observed within bilateral STS, particularly within the right hemisphere, during the observation of campaign relative to control videos. Furthermore, activation in these brain regions correlated with the subjects’ empathic expression. Our results develop our understanding of the role of STS in social cognition. Moreover, our data demonstrate the utility of neuroscientific methods when evaluating the effectiveness of campaign videos in terms of their ability to elicit empathic responses. Our study also demonstrates the utility of these specific stimuli for future neuroscientific research. PMID:25118071
Ultra High Definition Video from the International Space Station (Reel 1)
2015-06-15
The view of life in space is getting a major boost with the introduction of 4K Ultra High-Definition (UHD) video, providing an unprecedented look at what it's like to live and work aboard the International Space Station. This important new capability will allow researchers to acquire high resolution - high frame rate video to provide new insight into the vast array of experiments taking place every day. It will also bestow the most breathtaking views of planet Earth and space station activities ever acquired for consumption by those still dreaming of making the trip to outer space.
Open-source telemedicine platform for wireless medical video communication.
Panayides, A; Eleftheriou, I; Pantziaris, M
2013-01-01
An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN) and 3.5G high-speed packet access (HSPA) wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD) algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings.
Open-Source Telemedicine Platform for Wireless Medical Video Communication
Panayides, A.; Eleftheriou, I.; Pantziaris, M.
2013-01-01
An m-health system for real-time wireless communication of medical video based on open-source software is presented. The objective is to deliver a low-cost telemedicine platform which will allow for reliable remote diagnosis m-health applications such as emergency incidents, mass population screening, and medical education purposes. The performance of the proposed system is demonstrated using five atherosclerotic plaque ultrasound videos. The videos are encoded at the clinically acquired resolution, in addition to lower, QCIF, and CIF resolutions, at different bitrates, and four different encoding structures. Commercially available wireless local area network (WLAN) and 3.5G high-speed packet access (HSPA) wireless channels are used to validate the developed platform. Objective video quality assessment is based on PSNR ratings, following calibration using the variable frame delay (VFD) algorithm that removes temporal mismatch between original and received videos. Clinical evaluation is based on atherosclerotic plaque ultrasound video assessment protocol. Experimental results show that adequate diagnostic quality wireless medical video communications are realized using the designed telemedicine platform. HSPA cellular networks provide for ultrasound video transmission at the acquired resolution, while VFD algorithm utilization bridges objective and subjective ratings. PMID:23573082
Bernard, Florian; Deuter, Christian Eric; Gemmar, Peter; Schachinger, Hartmut
2013-10-01
Using the positions of the eyelids is an effective and contact-free way for the measurement of startle induced eye-blinks, which plays an important role in human psychophysiological research. To the best of our knowledge, no methods for an efficient detection and tracking of the exact eyelid contours in image sequences captured at high-speed exist that are conveniently usable by psychophysiological researchers. In this publication a semi-automatic model-based eyelid contour detection and tracking algorithm for the analysis of high-speed video recordings from an eye tracker is presented. As a large number of images have been acquired prior to method development it was important that our technique is able to deal with images that are recorded without any special parametrisation of the eye tracker. The method entails pupil detection, specular reflection removal and makes use of dynamic model adaption. In a proof-of-concept study we could achieve a correct detection rate of 90.6%. With this approach, we provide a feasible method to accurately assess eye-blinks from high-speed video recordings. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
High-Speed Video Analysis of Damped Harmonic Motion
ERIC Educational Resources Information Center
Poonyawatpornkul, J.; Wattanakasiwich, P.
2013-01-01
In this paper, we acquire and analyse high-speed videos of a spring-mass system oscillating in glycerin at different temperatures. Three cases of damped harmonic oscillation are investigated and analysed by using high-speed video at a rate of 120 frames s[superscript -1] and Tracker Video Analysis (Tracker) software. We present empirical data for…
The Use of Video-Tacheometric Technology for Documenting and Analysing Geometric Features of Objects
NASA Astrophysics Data System (ADS)
Woźniak, Marek; Świerczyńska, Ewa; Jastrzębski, Sławomir
2015-12-01
This paper analyzes selected aspects of the use of video-tacheometric technology for inventorying and documenting geometric features of objects. Data was collected with the use of the video-tacheometer Topcon Image Station IS-3 and the professional camera Canon EOS 5D Mark II. During the field work and the development of data the following experiments have been performed: multiple determination of the camera interior orientation parameters and distortion parameters of five lenses with different focal lengths, reflectorless measurements of profiles for the elevation and inventory of decorative surface wall of the building of Warsaw Ballet School. During the research the process of acquiring and integrating video-tacheometric data was analysed as well as the process of combining "point cloud" acquired by using video-tacheometer in the scanning process with independent photographs taken by a digital camera. On the basis of tests performed, utility of the use of video-tacheometric technology in geodetic surveys of geometrical features of buildings has been established.
Writing Assignments in Disguise: Lessons Learned Using Video Projects in the Classroom
NASA Astrophysics Data System (ADS)
Wade, P.; Courtney, A.
2012-12-01
This study describes the instructional approach of using student-created video documentaries as projects in an undergraduate non-science majors' Energy Perspectives science course. Four years of teaching this course provided many reflective teaching moments from which we have enhanced our instructional approach to teaching students how to construct a quality Ken Burn's style science video. Fundamental to a good video documentary is the story told via a narrative which involves significant writing, editing and rewriting. Many students primarily associate a video documentary with visual imagery and do not realize the importance of writing in the production of the video. Required components of the student-created video include: 1) select a topic, 2) conduct research, 3) write an outline, 4) write a narrative, 5) construct a project storyboard, 6) shoot or acquire video and photos (from legal sources), 7) record the narrative, 8) construct the video documentary, 9) edit and 10) finalize the project. Two knowledge survey instruments (administered pre- and post) were used for assessment purposes. One survey focused on the skills necessary to research and produce video documentaries and the second survey assessed students' content knowledge acquired from each documentary. This talk will focus on the components necessary for video documentaries and the instructional lessons learned over the years. Additionally, results from both surveys and student reflections of the video project will be shared.
Which button will I press? Preference for correctly ordered counting sequences in 18-month-olds.
Ip, Martin Ho Kwan; Imuta, Kana; Slaughter, Virginia
2018-04-16
Correct counting respects the stable order principle whereby the count terms are recited in a fixed order every time. The 4 experiments reported here tested whether precounting infants recognize and prefer correct stable-ordered counting. The authors introduced a novel preference paradigm in which infants could freely press two buttons to activate videos of counting events. In the "correct" counting video, number words were always recited in the canonical order ("1, 2, 3, 4, 5, 6"). The "incorrect" counting video was identical except that the number words were recited in a random order (e.g., "5, 3, 1, 6, 4, 2"). In Experiment 1, 18-month-olds (n = 21), but not 15-month-olds (n = 24), significantly preferred to press the button that activated correct counting events. Experiment 2 revealed that English-learning 18-month-olds' (n = 21) preference for stable-ordered counting disappeared when the counting was done in Japanese. By contrast, Experiment 3 showed that multilingual 18-month-olds (n = 24) preferred correct stable-ordered counting in an unfamiliar foreign language. In Experiment 4, multilingual 18-month-olds (N = 21) showed no preference for stable-ordered alphabet sequences, ruling out some alternative explanations for the Experiment 3 results. Overall these findings are consistent with the idea that implicit recognition of the stable order principle of counting is acquired by 18 months of age, and that learning more than one language may accelerate infants' understanding of abstract counting principles. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
NASA Astrophysics Data System (ADS)
Jenkins, Colleen; Jordan, Jay; Carlson, Jeff
2007-02-01
This paper presents parameter estimation techniques useful for detecting background changes in a video sequence with extreme foreground activity. A specific application of interest is automated detection of the covert placement of threats (e.g., a briefcase bomb) inside crowded public facilities. We propose that a histogram of pixel intensity acquired from a fixed mounted camera over time for a series of images will be a mixture of two Gaussian functions: the foreground probability distribution function and background probability distribution function. We will use Pearson's Method of Moments to separate the two probability distribution functions. The background function can then be "remembered" and changes in the background can be detected. Subsequent comparisons of background estimates are used to detect changes. Changes are flagged to alert security forces to the presence and location of potential threats. Results are presented that indicate the significant potential for robust parameter estimation techniques as applied to video surveillance.
Evaluation of experimental UAV video change detection
NASA Astrophysics Data System (ADS)
Bartelsen, J.; Saur, G.; Teutsch, C.
2016-10-01
During the last ten years, the availability of images acquired from unmanned aerial vehicles (UAVs) has been continuously increasing due to the improvements and economic success of flight and sensor systems. From our point of view, reliable and automatic image-based change detection may contribute to overcoming several challenging problems in military reconnaissance, civil security, and disaster management. Changes within a scene can be caused by functional activities, i.e., footprints or skid marks, excavations, or humidity penetration; these might be recognizable in aerial images, but are almost overlooked when change detection is executed manually. With respect to the circumstances, these kinds of changes may be an indication of sabotage, terroristic activity, or threatening natural disasters. Although image-based change detection is possible from both ground and aerial perspectives, in this paper we primarily address the latter. We have applied an extended approach to change detection as described by Saur and Kruger,1 and Saur et al.2 and have built upon the ideas of Saur and Bartelsen.3 The commercial simulation environment Virtual Battle Space 3 (VBS3) is used to simulate aerial "before" and "after" image acquisition concerning flight path, weather conditions and objects within the scene and to obtain synthetic videos. Video frames, which depict the same part of the scene, including "before" and "after" changes and not necessarily from the same perspective, are registered pixel-wise against each other by a photogrammetric concept, which is based on a homography. The pixel-wise registration is used to apply an automatic difference analysis, which, to a limited extent, is able to suppress typical errors caused by imprecise frame registration, sensor noise, vegetation and especially parallax effects. The primary concern of this paper is to seriously evaluate the possibilities and limitations of our current approach for image-based change detection with respect to the flight path, viewpoint change and parametrization. Hence, based on synthetic "before" and "after" videos of a simulated scene, we estimated the precision and recall of automatically detected changes. In addition and based on our approach, we illustrate the results showing the change detection in short, but real video sequences. Future work will improve the photogrammetric approach for frame registration, and extensive real video material, capable of change detection, will be acquired.
Video-Based Fingerprint Verification
Qin, Wei; Yin, Yilong; Liu, Lili
2013-01-01
Conventional fingerprint verification systems use only static information. In this paper, fingerprint videos, which contain dynamic information, are utilized for verification. Fingerprint videos are acquired by the same capture device that acquires conventional fingerprint images, and the user experience of providing a fingerprint video is the same as that of providing a single impression. After preprocessing and aligning processes, “inside similarity” and “outside similarity” are defined and calculated to take advantage of both dynamic and static information contained in fingerprint videos. Match scores between two matching fingerprint videos are then calculated by combining the two kinds of similarity. Experimental results show that the proposed video-based method leads to a relative reduction of 60 percent in the equal error rate (EER) in comparison to the conventional single impression-based method. We also analyze the time complexity of our method when different combinations of strategies are used. Our method still outperforms the conventional method, even if both methods have the same time complexity. Finally, experimental results demonstrate that the proposed video-based method can lead to better accuracy than the multiple impressions fusion method, and the proposed method has a much lower false acceptance rate (FAR) when the false rejection rate (FRR) is quite low. PMID:24008283
Localizing Target Structures in Ultrasound Video
Kwitt, R.; Vasconcelos, N.; Razzaque, S.; Aylward, S.
2013-01-01
The problem of localizing specific anatomic structures using ultrasound (US) video is considered. This involves automatically determining when an US probe is acquiring images of a previously defined object of interest, during the course of an US examination. Localization using US is motivated by the increased availability of portable, low-cost US probes, which inspire applications where inexperienced personnel and even first-time users acquire US data that is then sent to experts for further assessment. This process is of particular interest for routine examinations in underserved populations as well as for patient triage after natural disasters and large-scale accidents, where experts may be in short supply. The proposed localization approach is motivated by research in the area of dynamic texture analysis and leverages several recent advances in the field of activity recognition. For evaluation, we introduce an annotated and publicly available database of US video, acquired on three phantoms. Several experiments reveal the challenges of applying video analysis approaches to US images and demonstrate that good localization performance is possible with the proposed solution. PMID:23746488
Geographic Video 3d Data Model And Retrieval
NASA Astrophysics Data System (ADS)
Han, Z.; Cui, C.; Kong, Y.; Wu, H.
2014-04-01
Geographic video includes both spatial and temporal geographic features acquired through ground-based or non-ground-based cameras. With the popularity of video capture devices such as smartphones, the volume of user-generated geographic video clips has grown significantly and the trend of this growth is quickly accelerating. Such a massive and increasing volume poses a major challenge to efficient video management and query. Most of the today's video management and query techniques are based on signal level content extraction. They are not able to fully utilize the geographic information of the videos. This paper aimed to introduce a geographic video 3D data model based on spatial information. The main idea of the model is to utilize the location, trajectory and azimuth information acquired by sensors such as GPS receivers and 3D electronic compasses in conjunction with video contents. The raw spatial information is synthesized to point, line, polygon and solid according to the camcorder parameters such as focal length and angle of view. With the video segment and video frame, we defined the three categories geometry object using the geometry model of OGC Simple Features Specification for SQL. We can query video through computing the spatial relation between query objects and three categories geometry object such as VFLocation, VSTrajectory, VSFOView and VFFovCone etc. We designed the query methods using the structured query language (SQL) in detail. The experiment indicate that the model is a multiple objective, integration, loosely coupled, flexible and extensible data model for the management of geographic stereo video.
Video quality assesment using M-SVD
NASA Astrophysics Data System (ADS)
Tao, Peining; Eskicioglu, Ahmet M.
2007-01-01
Objective video quality measurement is a challenging problem in a variety of video processing application ranging from lossy compression to printing. An ideal video quality measure should be able to mimic the human observer. We present a new video quality measure, M-SVD, to evaluate distorted video sequences based on singular value decomposition. A computationally efficient approach is developed for full-reference (FR) video quality assessment. This measure is tested on the Video Quality Experts Group (VQEG) phase I FR-TV test data set. Our experiments show the graphical measure displays the amount of distortion as well as the distribution of error in all frames of the video sequence while the numerical measure has a good correlation with perceived video quality outperforms PSNR and other objective measures by a clear margin.
Merkel, Daniel; Brinkmann, Eckard; Kämmer, Joerg C; Köhler, Miriam; Wiens, Daniel; Derwahl, Karl-Michael
2015-09-01
The electronic colorization of grayscale B-mode sonograms using various color schemes aims to enhance the adaptability and practicability of B-mode sonography in daylight conditions. The purpose of this study was to determine the diagnostic effectiveness and importance of colorized B-mode sonography. Fifty-three video sequences of sonographic examinations of the liver were digitized and subsequently colorized in 2 different color combinations (yellow-brown and blue-white). The set of 53 images consisted of 33 with isoechoic masses, 8 with obvious lesions of the liver (hypoechoic or hyperechoic), and 12 with inconspicuous reference images of the liver. The video sequences were combined in a random order and edited into half-hour video clips. Isoechoic liver lesions were successfully detected in 58% of the yellow-brown video sequences and in 57% of the grayscale video sequences (P = .74, not significant). Fifty percent of the isoechoic liver lesions were successfully detected in the blue-white video sequences, as opposed to a 55% detection rate in the corresponding grayscale video sequences (P= .11, not significant). In 2 subgroups, significantly more liver lesions were detected with grayscale sonography compared to blue-white sonography. Yellow-brown-colorized B-mode sonography appears to be similarly effective for detection of isoechoic parenchymal liver lesions as traditional grayscale sonography. Blue-white colorization in B-mode sonography is probably not as effective as grayscale sonography, although a statistically significant disadvantage was shown only in the subgroup of hyperechoic liver lesions. © 2015 by the American Institute of Ultrasound in Medicine.
Human body motion capture from multi-image video sequences
NASA Astrophysics Data System (ADS)
D'Apuzzo, Nicola
2003-01-01
In this paper is presented a method to capture the motion of the human body from multi image video sequences without using markers. The process is composed of five steps: acquisition of video sequences, calibration of the system, surface measurement of the human body for each frame, 3-D surface tracking and tracking of key points. The image acquisition system is currently composed of three synchronized progressive scan CCD cameras and a frame grabber which acquires a sequence of triplet images. Self calibration methods are applied to gain exterior orientation of the cameras, the parameters of internal orientation and the parameters modeling the lens distortion. From the video sequences, two kinds of 3-D information are extracted: a three-dimensional surface measurement of the visible parts of the body for each triplet and 3-D trajectories of points on the body. The approach for surface measurement is based on multi-image matching, using the adaptive least squares method. A full automatic matching process determines a dense set of corresponding points in the triplets. The 3-D coordinates of the matched points are then computed by forward ray intersection using the orientation and calibration data of the cameras. The tracking process is also based on least squares matching techniques. Its basic idea is to track triplets of corresponding points in the three images through the sequence and compute their 3-D trajectories. The spatial correspondences between the three images at the same time and the temporal correspondences between subsequent frames are determined with a least squares matching algorithm. The results of the tracking process are the coordinates of a point in the three images through the sequence, thus the 3-D trajectory is determined by computing the 3-D coordinates of the point at each time step by forward ray intersection. Velocities and accelerations are also computed. The advantage of this tracking process is twofold: it can track natural points, without using markers; and it can track local surfaces on the human body. In the last case, the tracking process is applied to all the points matched in the region of interest. The result can be seen as a vector field of trajectories (position, velocity and acceleration). The last step of the process is the definition of selected key points of the human body. A key point is a 3-D region defined in the vector field of trajectories, whose size can vary and whose position is defined by its center of gravity. The key points are tracked in a simple way: the position at the next time step is established by the mean value of the displacement of all the trajectories inside its region. The tracked key points lead to a final result comparable to the conventional motion capture systems: 3-D trajectories of key points which can be afterwards analyzed and used for animation or medical purposes.
ERIC Educational Resources Information Center
Burton, Cami E.; Anderson, Darlene H.; Prater, Mary Anne; Dyches, Tina T.
2013-01-01
Researchers suggest that video-based interventions can provide increased opportunity for students with disabilities to acquire important academic and functional skills; however, little research exists regarding video-based interventions on the academic skills of students with autism and intellectual disability. We used a…
Method and Apparatus for Evaluating the Visual Quality of Processed Digital Video Sequences
NASA Technical Reports Server (NTRS)
Watson, Andrew B. (Inventor)
2002-01-01
A Digital Video Quality (DVQ) apparatus and method that incorporate a model of human visual sensitivity to predict the visibility of artifacts. The DVQ method and apparatus are used for the evaluation of the visual quality of processed digital video sequences and for adaptively controlling the bit rate of the processed digital video sequences without compromising the visual quality. The DVQ apparatus minimizes the required amount of memory and computation. The input to the DVQ apparatus is a pair of color image sequences: an original (R) non-compressed sequence, and a processed (T) sequence. Both sequences (R) and (T) are sampled, cropped, and subjected to color transformations. The sequences are then subjected to blocking and discrete cosine transformation, and the results are transformed to local contrast. The next step is a time filtering operation which implements the human sensitivity to different time frequencies. The results are converted to threshold units by dividing each discrete cosine transform coefficient by its respective visual threshold. At the next stage the two sequences are subtracted to produce an error sequence. The error sequence is subjected to a contrast masking operation, which also depends upon the reference sequence (R). The masked errors can be pooled in various ways to illustrate the perceptual error over various dimensions, and the pooled error can be converted to a visual quality measure.
NASA Astrophysics Data System (ADS)
Kerekes, Ryan A.; Gleason, Shaun S.; Trivedi, Niraj; Solecki, David J.
2010-03-01
Segmentation, tracking, and tracing of neurons in video imagery are important steps in many neuronal migration studies and can be inaccurate and time-consuming when performed manually. In this paper, we present an automated method for tracing the leading and trailing processes of migrating neurons in time-lapse image stacks acquired with a confocal fluorescence microscope. In our approach, we first locate and track the soma of the cell of interest by smoothing each frame and tracking the local maxima through the sequence. We then trace the leading process in each frame by starting at the center of the soma and stepping repeatedly in the most likely direction of the leading process. This direction is found at each step by examining second derivatives of fluorescent intensity along curves of constant radius around the current point. Tracing terminates after a fixed number of steps or when fluorescent intensity drops below a fixed threshold. We evolve the resulting trace to form an improved trace that more closely follows the approximate centerline of the leading process. We apply a similar algorithm to the trailing process of the cell by starting the trace in the opposite direction. We demonstrate our algorithm on two time-lapse confocal video sequences of migrating cerebellar granule neurons (CGNs). We show that the automated traces closely approximate ground truth traces to within 1 or 2 pixels on average. Additionally, we compute line intensity profiles of fluorescence along the automated traces and quantitatively demonstrate their similarity to manually generated profiles in terms of fluorescence peak locations.
Yao, Guangle; Lei, Tao; Zhong, Jiandan; Jiang, Ping; Jia, Wenwu
2017-01-01
Background subtraction (BS) is one of the most commonly encountered tasks in video analysis and tracking systems. It distinguishes the foreground (moving objects) from the video sequences captured by static imaging sensors. Background subtraction in remote scene infrared (IR) video is important and common to lots of fields. This paper provides a Remote Scene IR Dataset captured by our designed medium-wave infrared (MWIR) sensor. Each video sequence in this dataset is identified with specific BS challenges and the pixel-wise ground truth of foreground (FG) for each frame is also provided. A series of experiments were conducted to evaluate BS algorithms on this proposed dataset. The overall performance of BS algorithms and the processor/memory requirements were compared. Proper evaluation metrics or criteria were employed to evaluate the capability of each BS algorithm to handle different kinds of BS challenges represented in this dataset. The results and conclusions in this paper provide valid references to develop new BS algorithm for remote scene IR video sequence, and some of them are not only limited to remote scene or IR video sequence but also generic for background subtraction. The Remote Scene IR dataset and the foreground masks detected by each evaluated BS algorithm are available online: https://github.com/JerryYaoGl/BSEvaluationRemoteSceneIR. PMID:28837112
Co-Located Collaborative Learning Video Game with Single Display Groupware
ERIC Educational Resources Information Center
Infante, Cristian; Weitz, Juan; Reyes, Tomas; Nussbaum, Miguel; Gomez, Florencia; Radovic, Darinka
2010-01-01
Role Game is a co-located CSCL video game played by three students sitting at one machine sharing a single screen, each with their own input device. Inspired by video console games, Role Game enables students to learn by doing, acquiring social abilities and mastering subject matter in a context of co-located collaboration. After describing the…
Constructing storyboards based on hierarchical clustering analysis
NASA Astrophysics Data System (ADS)
Hasebe, Satoshi; Sami, Mustafa M.; Muramatsu, Shogo; Kikuchi, Hisakazu
2005-07-01
There are growing needs for quick preview of video contents for the purpose of improving accessibility of video archives as well as reducing network traffics. In this paper, a storyboard that contains a user-specified number of keyframes is produced from a given video sequence. It is based on hierarchical cluster analysis of feature vectors that are derived from wavelet coefficients of video frames. Consistent use of extracted feature vectors is the key to avoid a repetition of computationally-intensive parsing of the same video sequence. Experimental results suggest that a significant reduction in computational time is gained by this strategy.
Tracing cell lineages in videos of lens-free microscopy.
Rempfler, Markus; Stierle, Valentin; Ditzel, Konstantin; Kumar, Sanjeev; Paulitschke, Philipp; Andres, Bjoern; Menze, Bjoern H
2018-06-05
In vitro experiments with cultured cells are essential for studying their growth and migration pattern and thus, for gaining a better understanding of cancer progression and its treatment. Recent progress in lens-free microscopy (LFM) has rendered it an inexpensive tool for label-free, continuous live cell imaging, yet there is only little work on analysing such time-lapse image sequences. We propose (1) a cell detector for LFM images based on fully convolutional networks and residual learning, and (2) a probabilistic model based on moral lineage tracing that explicitly handles multiple detections and temporal successor hypotheses by clustering and tracking simultaneously. (3) We benchmark our method in terms of detection and tracking scores on a dataset of three annotated sequences of several hours of LFM, where we demonstrate our method to produce high quality lineages. (4) We evaluate its performance on a somewhat more challenging problem: estimating cell lineages from the LFM sequence as would be possible from a corresponding fluorescence microscopy sequence. We present experiments on 16 LFM sequences for which we acquired fluorescence microscopy in parallel and generated annotations from them. Finally, (5) we showcase our methods effectiveness for quantifying cell dynamics in an experiment with skin cancer cells. Copyright © 2018 Elsevier B.V. All rights reserved.
Multimodal Speaker Diarization.
Noulas, A; Englebienne, G; Krose, B J A
2012-01-01
We present a novel probabilistic framework that fuses information coming from the audio and video modality to perform speaker diarization. The proposed framework is a Dynamic Bayesian Network (DBN) that is an extension of a factorial Hidden Markov Model (fHMM) and models the people appearing in an audiovisual recording as multimodal entities that generate observations in the audio stream, the video stream, and the joint audiovisual space. The framework is very robust to different contexts, makes no assumptions about the location of the recording equipment, and does not require labeled training data as it acquires the model parameters using the Expectation Maximization (EM) algorithm. We apply the proposed model to two meeting videos and a news broadcast video, all of which come from publicly available data sets. The results acquired in speaker diarization are in favor of the proposed multimodal framework, which outperforms the single modality analysis results and improves over the state-of-the-art audio-based speaker diarization.
Detection and tracking of gas plumes in LWIR hyperspectral video sequence data
NASA Astrophysics Data System (ADS)
Gerhart, Torin; Sunu, Justin; Lieu, Lauren; Merkurjev, Ekaterina; Chang, Jen-Mei; Gilles, Jérôme; Bertozzi, Andrea L.
2013-05-01
Automated detection of chemical plumes presents a segmentation challenge. The segmentation problem for gas plumes is difficult due to the diffusive nature of the cloud. The advantage of considering hyperspectral images in the gas plume detection problem over the conventional RGB imagery is the presence of non-visual data, allowing for a richer representation of information. In this paper we present an effective method of visualizing hyperspectral video sequences containing chemical plumes and investigate the effectiveness of segmentation techniques on these post-processed videos. Our approach uses a combination of dimension reduction and histogram equalization to prepare the hyperspectral videos for segmentation. First, Principal Components Analysis (PCA) is used to reduce the dimension of the entire video sequence. This is done by projecting each pixel onto the first few Principal Components resulting in a type of spectral filter. Next, a Midway method for histogram equalization is used. These methods redistribute the intensity values in order to reduce icker between frames. This properly prepares these high-dimensional video sequences for more traditional segmentation techniques. We compare the ability of various clustering techniques to properly segment the chemical plume. These include K-means, spectral clustering, and the Ginzburg-Landau functional.
NASA Astrophysics Data System (ADS)
Chen, Xinyuan; Song, Li; Yang, Xiaokang
2016-09-01
Video denoising can be described as the problem of mapping from a specific length of noisy frames to clean one. We propose a deep architecture based on Recurrent Neural Network (RNN) for video denoising. The model learns a patch-based end-to-end mapping between the clean and noisy video sequences. It takes the corrupted video sequences as the input and outputs the clean one. Our deep network, which we refer to as deep Recurrent Neural Networks (deep RNNs or DRNNs), stacks RNN layers where each layer receives the hidden state of the previous layer as input. Experiment shows (i) the recurrent architecture through temporal domain extracts motion information and does favor to video denoising, and (ii) deep architecture have large enough capacity for expressing mapping relation between corrupted videos as input and clean videos as output, furthermore, (iii) the model has generality to learned different mappings from videos corrupted by different types of noise (e.g., Poisson-Gaussian noise). By training on large video databases, we are able to compete with some existing video denoising methods.
Human silhouette matching based on moment invariants
NASA Astrophysics Data System (ADS)
Sun, Yong-Chao; Qiu, Xian-Jie; Xia, Shi-Hong; Wang, Zhao-Qi
2005-07-01
This paper aims to apply the method of silhouette matching based on moment invariants to infer the human motion parameters from video sequences of single monocular uncalibrated camera. Currently, there are two ways of tracking human motion: Marker and Markerless. While a hybrid framework is introduced in this paper to recover the input video contents. A standard 3D motion database is built up by marker technique in advance. Given a video sequences, human silhouettes are extracted as well as the viewpoint information of the camera which would be utilized to project the standard 3D motion database onto the 2D one. Therefore, the video recovery problem is formulated as a matching issue of finding the most similar body pose in standard 2D library with the one in video image. The framework is applied to the special trampoline sport where we can obtain the complicated human motion parameters in the single camera video sequences, and a lot of experiments are demonstrated that this approach is feasible in the field of monocular video-based 3D motion reconstruction.
Woo, Kevin L; Rieucau, Guillaume
2008-07-01
The increasing use of the video playback technique in behavioural ecology reveals a growing need to ensure better control of the visual stimuli that focal animals experience. Technological advances now allow researchers to develop computer-generated animations instead of using video sequences of live-acting demonstrators. However, care must be taken to match the motion characteristics (speed and velocity) of the animation to the original video source. Here, we presented a tool based on the use of an optic flow analysis program to measure the resemblance of motion characteristics of computer-generated animations compared to videos of live-acting animals. We examined three distinct displays (tail-flick (TF), push-up body rock (PUBR), and slow arm wave (SAW)) exhibited by animations of Jacky dragons (Amphibolurus muricatus) that were compared to the original video sequences of live lizards. We found no significant differences between the motion characteristics of videos and animations across all three displays. Our results showed that our animations are similar the speed and velocity features of each display. Researchers need to ensure that similar motion characteristics in animation and video stimuli are represented, and this feature is a critical component in the future success of the video playback technique.
ERIC Educational Resources Information Center
Robson, Diane; Durkee, Patrick
2012-01-01
The work of collection development in academic video game collections is at a crucial point of transformation--gaming librarians are ready to expand beyond console games collected in disc and cartridge format to the world of Internet games. At the same time, forms and genres of video games such as serious and independent games are increasingly…
Performance evaluation of the intra compression in the video coding standards
NASA Astrophysics Data System (ADS)
Abramowski, Andrzej
2015-09-01
The article presents a comparison of the Intra prediction algorithms in the current state-of-the-art video coding standards, including MJPEG 2000, VP8, VP9, H.264/AVC and H.265/HEVC. The effectiveness of techniques employed by each standard is evaluated in terms of compression efficiency and average encoding time. The compression efficiency is measured using BD-PSNR and BD-RATE metrics with H.265/HEVC results as an anchor. Tests are performed on a set of video sequences, composed of sequences gathered by Joint Collaborative Team on Video Coding during the development of the H.265/HEVC standard and 4K sequences provided by Ultra Video Group. According to results, H.265/HEVC provides significant bit-rate savings at the expense of computational complexity, while VP9 may be regarded as a compromise between the efficiency and required encoding time.
Video-assisted segmentation of speech and audio track
NASA Astrophysics Data System (ADS)
Pandit, Medha; Yusoff, Yusseri; Kittler, Josef; Christmas, William J.; Chilton, E. H. S.
1999-08-01
Video database research is commonly concerned with the storage and retrieval of visual information invovling sequence segmentation, shot representation and video clip retrieval. In multimedia applications, video sequences are usually accompanied by a sound track. The sound track contains potential cues to aid shot segmentation such as different speakers, background music, singing and distinctive sounds. These different acoustic categories can be modeled to allow for an effective database retrieval. In this paper, we address the problem of automatic segmentation of audio track of multimedia material. This audio based segmentation can be combined with video scene shot detection in order to achieve partitioning of the multimedia material into semantically significant segments.
Video enhancement workbench: an operational real-time video image processing system
NASA Astrophysics Data System (ADS)
Yool, Stephen R.; Van Vactor, David L.; Smedley, Kirk G.
1993-01-01
Video image sequences can be exploited in real-time, giving analysts rapid access to information for military or criminal investigations. Video-rate dynamic range adjustment subdues fluctuations in image intensity, thereby assisting discrimination of small or low- contrast objects. Contrast-regulated unsharp masking enhances differentially shadowed or otherwise low-contrast image regions. Real-time removal of localized hotspots, when combined with automatic histogram equalization, may enhance resolution of objects directly adjacent. In video imagery corrupted by zero-mean noise, real-time frame averaging can assist resolution and location of small or low-contrast objects. To maximize analyst efficiency, lengthy video sequences can be screened automatically for low-frequency, high-magnitude events. Combined zoom, roam, and automatic dynamic range adjustment permit rapid analysis of facial features captured by video cameras recording crimes in progress. When trying to resolve small objects in murky seawater, stereo video places the moving imagery in an optimal setting for human interpretation.
Video change detection for fixed wing UAVs
NASA Astrophysics Data System (ADS)
Bartelsen, Jan; Müller, Thomas; Ring, Jochen; Mück, Klaus; Brüstle, Stefan; Erdnüß, Bastian; Lutz, Bastian; Herbst, Theresa
2017-10-01
In this paper we proceed the work of Bartelsen et al.1 We present the draft of a process chain for an image based change detection which is designed for videos acquired by fixed wing unmanned aerial vehicles (UAVs). From our point of view, automatic video change detection for aerial images can be useful to recognize functional activities which are typically caused by the deployment of improvised explosive devices (IEDs), e.g. excavations, skid marks, footprints, left-behind tooling equipment, and marker stones. Furthermore, in case of natural disasters, like flooding, imminent danger can be recognized quickly. Due to the necessary flight range, we concentrate on fixed wing UAVs. Automatic change detection can be reduced to a comparatively simple photogrammetric problem when the perspective change between the "before" and "after" image sets is kept as small as possible. Therefore, the aerial image acquisition demands a mission planning with a clear purpose including flight path and sensor configuration. While the latter can be enabled simply by a fixed and meaningful adjustment of the camera, ensuring a small perspective change for "before" and "after" videos acquired by fixed wing UAVs is a challenging problem. Concerning this matter, we have performed tests with an advanced commercial off the shelf (COTS) system which comprises a differential GPS and autopilot system estimating the repetition accuracy of its trajectory. Although several similar approaches have been presented,23 as far as we are able to judge, the limits for this important issue are not estimated so far. Furthermore, we design a process chain to enable the practical utilization of video change detection. It consists of a front-end of a database to handle large amounts of video data, an image processing and change detection implementation, and the visualization of the results. We apply our process chain on the real video data acquired by the advanced COTS fixed wing UAV and synthetic data. For the image processing and change detection, we use the approach of Muller.4 Although it was developed for unmanned ground vehicles (UGVs), it enables a near real time video change detection for aerial videos. Concluding, we discuss the demands on sensor systems in the matter of change detection.
Standardized access, display, and retrieval of medical video
NASA Astrophysics Data System (ADS)
Bellaire, Gunter; Steines, Daniel; Graschew, Georgi; Thiel, Andreas; Bernarding, Johannes; Tolxdorff, Thomas; Schlag, Peter M.
1999-05-01
The system presented here enhances documentation and data- secured, second-opinion facilities by integrating video sequences into DICOM 3.0. We present an implementation for a medical video server extended by a DICOM interface. Security mechanisms conforming with DICOM are integrated to enable secure internet access. Digital video documents of diagnostic and therapeutic procedures should be examined regarding the clip length and size necessary for second opinion and manageable with today's hardware. Image sources relevant for this paper include 3D laparoscope, 3D surgical microscope, 3D open surgery camera, synthetic video, and monoscopic endoscopes, etc. The global DICOM video concept and three special workplaces of distinct applications are described. Additionally, an approach is presented to analyze the motion of the endoscopic camera for future automatic video-cutting. Digital stereoscopic video sequences are especially in demand for surgery . Therefore DSVS are also integrated into the DICOM video concept. Results are presented describing the suitability of stereoscopic display techniques for the operating room.
Algorithm for Video Summarization of Bronchoscopy Procedures
2011-01-01
Background The duration of bronchoscopy examinations varies considerably depending on the diagnostic and therapeutic procedures used. It can last more than 20 minutes if a complex diagnostic work-up is included. With wide access to videobronchoscopy, the whole procedure can be recorded as a video sequence. Common practice relies on an active attitude of the bronchoscopist who initiates the recording process and usually chooses to archive only selected views and sequences. However, it may be important to record the full bronchoscopy procedure as documentation when liability issues are at stake. Furthermore, an automatic recording of the whole procedure enables the bronchoscopist to focus solely on the performed procedures. Video recordings registered during bronchoscopies include a considerable number of frames of poor quality due to blurry or unfocused images. It seems that such frames are unavoidable due to the relatively tight endobronchial space, rapid movements of the respiratory tract due to breathing or coughing, and secretions which occur commonly in the bronchi, especially in patients suffering from pulmonary disorders. Methods The use of recorded bronchoscopy video sequences for diagnostic, reference and educational purposes could be considerably extended with efficient, flexible summarization algorithms. Thus, the authors developed a prototype system to create shortcuts (called summaries or abstracts) of bronchoscopy video recordings. Such a system, based on models described in previously published papers, employs image analysis methods to exclude frames or sequences of limited diagnostic or education value. Results The algorithm for the selection or exclusion of specific frames or shots from video sequences recorded during bronchoscopy procedures is based on several criteria, including automatic detection of "non-informative", frames showing the branching of the airways and frames including pathological lesions. Conclusions The paper focuses on the challenge of generating summaries of bronchoscopy video recordings. PMID:22185344
Motion video analysis using planar parallax
NASA Astrophysics Data System (ADS)
Sawhney, Harpreet S.
1994-04-01
Motion and structure analysis in video sequences can lead to efficient descriptions of objects and their motions. Interesting events in videos can be detected using such an analysis--for instance independent object motion when the camera itself is moving, figure-ground segregation based on the saliency of a structure compared to its surroundings. In this paper we present a method for 3D motion and structure analysis that uses a planar surface in the environment as a reference coordinate system to describe a video sequence. The motion in the video sequence is described as the motion of the reference plane, and the parallax motion of all the non-planar components of the scene. It is shown how this method simplifies the otherwise hard general 3D motion analysis problem. In addition, a natural coordinate system in the environment is used to describe the scene which can simplify motion based segmentation. This work is a part of an ongoing effort in our group towards video annotation and analysis for indexing and retrieval. Results from a demonstration system being developed are presented.
47 CFR 76.503 - National subscriber limits.
Code of Federal Regulations, 2010 CFR
2010-10-01
... in an incumbent cable franchise. (g) Prior to acquiring additional multichannel video-programming..., directly or indirectly, in the management or operation of the video programming-related activities of the... interest holder is not materially involved, directly or indirectly, in the management or operation of the...
Synthesis of Speaker Facial Movement to Match Selected Speech Sequences
NASA Technical Reports Server (NTRS)
Scott, K. C.; Kagels, D. S.; Watson, S. H.; Rom, H.; Wright, J. R.; Lee, M.; Hussey, K. J.
1994-01-01
A system is described which allows for the synthesis of a video sequence of a realistic-appearing talking human head. A phonic based approach is used to describe facial motion; image processing rather than physical modeling techniques are used to create video frames.
The MaizeGDB Genome Browser tutorial: one example of database outreach to biologists via video.
Harper, Lisa C; Schaeffer, Mary L; Thistle, Jordan; Gardiner, Jack M; Andorf, Carson M; Campbell, Darwin A; Cannon, Ethalinda K S; Braun, Bremen L; Birkett, Scott M; Lawrence, Carolyn J; Sen, Taner Z
2011-01-01
Video tutorials are an effective way for researchers to quickly learn how to use online tools offered by biological databases. At MaizeGDB, we have developed a number of video tutorials that demonstrate how to use various tools and explicitly outline the caveats researchers should know to interpret the information available to them. One such popular video currently available is 'Using the MaizeGDB Genome Browser', which describes how the maize genome was sequenced and assembled as well as how the sequence can be visualized and interacted with via the MaizeGDB Genome Browser. Database
NASA Astrophysics Data System (ADS)
Bulan, Orhan; Bernal, Edgar A.; Loce, Robert P.; Wu, Wencheng
2013-03-01
Video cameras are widely deployed along city streets, interstate highways, traffic lights, stop signs and toll booths by entities that perform traffic monitoring and law enforcement. The videos captured by these cameras are typically compressed and stored in large databases. Performing a rapid search for a specific vehicle within a large database of compressed videos is often required and can be a time-critical life or death situation. In this paper, we propose video compression and decompression algorithms that enable fast and efficient vehicle or, more generally, event searches in large video databases. The proposed algorithm selects reference frames (i.e., I-frames) based on a vehicle having been detected at a specified position within the scene being monitored while compressing a video sequence. A search for a specific vehicle in the compressed video stream is performed across the reference frames only, which does not require decompression of the full video sequence as in traditional search algorithms. Our experimental results on videos captured in a local road show that the proposed algorithm significantly reduces the search space (thus reducing time and computational resources) in vehicle search tasks within compressed video streams, particularly those captured in light traffic volume conditions.
Variability sensitivity of dynamic texture based recognition in clinical CT data
NASA Astrophysics Data System (ADS)
Kwitt, Roland; Razzaque, Sharif; Lowell, Jeffrey; Aylward, Stephen
2014-03-01
Dynamic texture recognition using a database of template models has recently shown promising results for the task of localizing anatomical structures in Ultrasound video. In order to understand its clinical value, it is imperative to study the sensitivity with respect to inter-patient variability as well as sensitivity to acquisition parameters such as Ultrasound probe angle. Fully addressing patient and acquisition variability issues, however, would require a large database of clinical Ultrasound from many patients, acquired in a multitude of controlled conditions, e.g., using a tracked transducer. Since such data is not readily attainable, we advocate an alternative evaluation strategy using abdominal CT data as a surrogate. In this paper, we describe how to replicate Ultrasound variabilities by extracting subvolumes from CT and interpreting the image material as an ordered sequence of video frames. Utilizing this technique, and based on a database of abdominal CT from 45 patients, we report recognition results on an organ (kidney) recognition task, where we try to discriminate kidney subvolumes/videos from a collection of randomly sampled negative instances. We demonstrate that (1) dynamic texture recognition is relatively insensitive to inter-patient variation while (2) viewing angle variability needs to be accounted for in the template database. Since naively extending the template database to counteract variability issues can lead to impractical database sizes, we propose an alternative strategy based on automated identification of a small set of representative models.
Evaluation of privacy in high dynamic range video sequences
NASA Astrophysics Data System (ADS)
Řeřábek, Martin; Yuan, Lin; Krasula, Lukáš; Korshunov, Pavel; Fliegel, Karel; Ebrahimi, Touradj
2014-09-01
The ability of high dynamic range (HDR) to capture details in environments with high contrast has a significant impact on privacy in video surveillance. However, the extent to which HDR imaging affects privacy, when compared to a typical low dynamic range (LDR) imaging, is neither well studied nor well understood. To achieve such an objective, a suitable dataset of images and video sequences is needed. Therefore, we have created a publicly available dataset of HDR video for privacy evaluation PEViD-HDR, which is an HDR extension of an existing Privacy Evaluation Video Dataset (PEViD). PEViD-HDR video dataset can help in the evaluations of privacy protection tools, as well as for showing the importance of HDR imaging in video surveillance applications and its influence on the privacy-intelligibility trade-off. We conducted a preliminary subjective experiment demonstrating the usability of the created dataset for evaluation of privacy issues in video. The results confirm that a tone-mapped HDR video contains more privacy sensitive information and details compared to a typical LDR video.
Deriving video content type from HEVC bitstream semantics
NASA Astrophysics Data System (ADS)
Nightingale, James; Wang, Qi; Grecos, Christos; Goma, Sergio R.
2014-05-01
As network service providers seek to improve customer satisfaction and retention levels, they are increasingly moving from traditional quality of service (QoS) driven delivery models to customer-centred quality of experience (QoE) delivery models. QoS models only consider metrics derived from the network however, QoE models also consider metrics derived from within the video sequence itself. Various spatial and temporal characteristics of a video sequence have been proposed, both individually and in combination, to derive methods of classifying video content either on a continuous scale or as a set of discrete classes. QoE models can be divided into three broad categories, full reference, reduced reference and no-reference models. Due to the need to have the original video available at the client for comparison, full reference metrics are of limited practical value in adaptive real-time video applications. Reduced reference metrics often require metadata to be transmitted with the bitstream, while no-reference metrics typically operate in the decompressed domain at the client side and require significant processing to extract spatial and temporal features. This paper proposes a heuristic, no-reference approach to video content classification which is specific to HEVC encoded bitstreams. The HEVC encoder already makes use of spatial characteristics to determine partitioning of coding units and temporal characteristics to determine the splitting of prediction units. We derive a function which approximates the spatio-temporal characteristics of the video sequence by using the weighted averages of the depth at which the coding unit quadtree is split and the prediction mode decision made by the encoder to estimate spatial and temporal characteristics respectively. Since the video content type of a sequence is determined by using high level information parsed from the video stream, spatio-temporal characteristics are identified without the need for full decoding and can be used in a timely manner to aid decision making in QoE oriented adaptive real time streaming.
High efficiency video coding for ultrasound video communication in m-health systems.
Panayides, A; Antoniou, Z; Pattichis, M S; Pattichis, C S; Constantinides, A G
2012-01-01
Emerging high efficiency video compression methods and wider availability of wireless network infrastructure will significantly advance existing m-health applications. For medical video communications, the emerging video compression and network standards support low-delay and high-resolution video transmission, at the clinically acquired resolution and frame rates. Such advances are expected to further promote the adoption of m-health systems for remote diagnosis and emergency incidents in daily clinical practice. This paper compares the performance of the emerging high efficiency video coding (HEVC) standard to the current state-of-the-art H.264/AVC standard. The experimental evaluation, based on five atherosclerotic plaque ultrasound videos encoded at QCIF, CIF, and 4CIF resolutions demonstrates that 50% reductions in bitrate requirements is possible for equivalent clinical quality.
Telesign: a videophone system for sign language distant communication
NASA Astrophysics Data System (ADS)
Mozelle, Gerard; Preteux, Francoise J.; Viallet, Jean-Emmanuel
1998-09-01
This paper presents a low bit rate videophone system for deaf people communicating by means of sign language. Classic video conferencing systems have focused on head and shoulders sequences which are not well-suited for sign language video transmission since hearing impaired people also use their hands and arms to communicate. To address the above-mentioned functionality, we have developed a two-step content-based video coding system based on: (1) A segmentation step. Four or five video objects (VO) are extracted using a cooperative approach between color-based and morphological segmentation. (2) VO coding are achieved by using a standardized MPEG-4 video toolbox. Results of encoded sign language video sequences, presented for three target bit rates (32 kbits/s, 48 kbits/s and 64 kbits/s), demonstrate the efficiency of the approach presented in this paper.
Non-mydriatic, wide field, fundus video camera
NASA Astrophysics Data System (ADS)
Hoeher, Bernhard; Voigtmann, Peter; Michelson, Georg; Schmauss, Bernhard
2014-02-01
We describe a method we call "stripe field imaging" that is capable of capturing wide field color fundus videos and images of the human eye at pupil sizes of 2mm. This means that it can be used with a non-dilated pupil even with bright ambient light. We realized a mobile demonstrator to prove the method and we could acquire color fundus videos of subjects successfully. We designed the demonstrator as a low-cost device consisting of mass market components to show that there is no major additional technical outlay to realize the improvements we propose. The technical core idea of our method is breaking the rotational symmetry in the optical design that is given in many conventional fundus cameras. By this measure we could extend the possible field of view (FOV) at a pupil size of 2mm from a circular field with 20° in diameter to a square field with 68° by 18° in size. We acquired a fundus video while the subject was slightly touching and releasing the lid. The resulting video showed changes at vessels in the region of the papilla and a change of the paleness of the papilla.
Use of video in the Virginia Highway and Transportation Research Council.
DOT National Transportation Integrated Search
1984-01-01
Described in this report is the video equipment recently acquired by the Council and how it has been used to date. Also discussed are the many other ways this equipment can and probably will be used in the future, not only at the Council, but in oper...
Xu, Yilei; Roy-Chowdhury, Amit K
2007-05-01
In this paper, we present a theory for combining the effects of motion, illumination, 3D structure, albedo, and camera parameters in a sequence of images obtained by a perspective camera. We show that the set of all Lambertian reflectance functions of a moving object, at any position, illuminated by arbitrarily distant light sources, lies "close" to a bilinear subspace consisting of nine illumination variables and six motion variables. This result implies that, given an arbitrary video sequence, it is possible to recover the 3D structure, motion, and illumination conditions simultaneously using the bilinear subspace formulation. The derivation builds upon existing work on linear subspace representations of reflectance by generalizing it to moving objects. Lighting can change slowly or suddenly, locally or globally, and can originate from a combination of point and extended sources. We experimentally compare the results of our theory with ground truth data and also provide results on real data by using video sequences of a 3D face and the entire human body with various combinations of motion and illumination directions. We also show results of our theory in estimating 3D motion and illumination model parameters from a video sequence.
The MaizeGDB Genome Browser tutorial: one example of database outreach to biologists via video
Harper, Lisa C.; Schaeffer, Mary L.; Thistle, Jordan; Gardiner, Jack M.; Andorf, Carson M.; Campbell, Darwin A.; Cannon, Ethalinda K.S.; Braun, Bremen L.; Birkett, Scott M.; Lawrence, Carolyn J.; Sen, Taner Z.
2011-01-01
Video tutorials are an effective way for researchers to quickly learn how to use online tools offered by biological databases. At MaizeGDB, we have developed a number of video tutorials that demonstrate how to use various tools and explicitly outline the caveats researchers should know to interpret the information available to them. One such popular video currently available is ‘Using the MaizeGDB Genome Browser’, which describes how the maize genome was sequenced and assembled as well as how the sequence can be visualized and interacted with via the MaizeGDB Genome Browser. Database URL: http://www.maizegdb.org/ PMID:21565781
Ns-scaled time-gated fluorescence lifetime imaging for forensic document examination
NASA Astrophysics Data System (ADS)
Zhong, Xin; Wang, Xinwei; Zhou, Yan
2018-01-01
A method of ns-scaled time-gated fluorescence lifetime imaging (TFLI) is proposed to distinguish different fluorescent substances in forensic document examination. Compared with Video Spectral Comparator (VSC) which can examine fluorescence intensity images only, TFLI can detect questioned documents like falsification or alteration. TFLI system can enhance weak signal by accumulation method. The two fluorescence intensity images of the interval delay time tg are acquired by ICCD and fitted into fluorescence lifetime image. The lifetimes of fluorescence substances are represented by different colors, which make it easy to detect the fluorescent substances and the sequence of handwritings. It proves that TFLI is a powerful tool for forensic document examination. Furthermore, the advantages of TFLI system are ns-scaled precision preservation and powerful capture capability.
Innovative Video Diagnostic Equipment for Material Science
NASA Technical Reports Server (NTRS)
Capuano, G.; Titomanlio, D.; Soellner, W.; Seidel, A.
2012-01-01
Materials science experiments under microgravity increasingly rely on advanced optical systems to determine the physical properties of the samples under investigation. This includes video systems with high spatial and temporal resolution. The acquisition, handling, storage and transmission to ground of the resulting video data are very challenging. Since the available downlink data rate is limited, the capability to compress the video data significantly without compromising the data quality is essential. We report on the development of a Digital Video System (DVS) for EML (Electro Magnetic Levitator) which provides real-time video acquisition, high compression using advanced Wavelet algorithms, storage and transmission of a continuous flow of video with different characteristics in terms of image dimensions and frame rates. The DVS is able to operate with the latest generation of high-performance cameras acquiring high resolution video images up to 4Mpixels@60 fps or high frame rate video images up to about 1000 fps@512x512pixels.
Weber, Uwe; Constantinescu, Mihai A; Woermann, Ulrich; Schmitz, Felix; Schnabel, Kai
2016-01-01
Various different learning methods are available for planning tuition regarding the introduction to surgical hand disinfection. These learning methods should help to organise and deal with this topic. The use of a video film is an alternative to conventional tuition due to the real presentation possibilities of practical demonstration. This study examines by way of comparison which form of communication is more effective for learning and applying surgical hand disinfection for medical students in their first year of studies: video-based instruction or conventional tuition. A total of 50 first-year medical students were randomly allocated either to the "Conventional Instruction" (CI) study group or to the "Video-based Instruction" (VI) study group. The conventional instruction was carried out by an experienced nurse preceptor/nurse educator for the operating theatre who taught the preparatory measures and the actual procedure in a two-minute lesson. The second group watched a two-minute video sequence with identical content. Afterwards, both groups demonstrated practically the knowledge they had acquired at an individual practical test station. The quality (a) of the preparation and (b) of the procedure as well as (c) the quality of the results was assessed by 6 blind experts using a check list. The acceptability of the respective teaching method was also asked about using a questionnaire. The group performance did not differ either in the preparation (t=-78, p<0.44) or in the quality (t=-99, p<0.34). With respect to performance, it was possible to demonstrate a strong treatment effect. In the practical (t=-3.33, p<0.002, d=0.943) and in the total score (t=-2.65, p<0.011, d=0.751), the group with video-based instruction achieved a significantly better result. In response to the question as to which of the two learning methods they would prefer, the significant majority (60.4%) of students stated video instruction. In this study, the use of the video-based instruction emerged as the more effective teaching method for learning surgical hand disinfection for medical students and is preferable to conventional instruction. The video instruction is associated with a higher learning effectiveness, efficiency and acceptability.
NASA Astrophysics Data System (ADS)
Bartolini, Franco; Pasquini, Cristina; Piva, Alessandro
2001-04-01
The recent development of video compression algorithms allowed the diffusion of systems for the transmission of video sequences over data networks. However, the transmission over error prone mobile communication channels is yet an open issue. In this paper, a system developed for the real time transmission of H263 video coded sequences over TETRA mobile networks is presented. TETRA is an open digital trunked radio standard defined by the European Telecommunications Standardization Institute developed for professional mobile radio users, providing full integration of voice and data services. Experimental tests demonstrate that, in spite of the low frame rate allowed by the SW only implementation of the decoder and by the low channel rate a video compression technique such as that complying with the H263 standard, is still preferable to a simpler but less effective frame based compression system.
Mosaicking Techniques for Deep Submergence Vehicle Video Imagery - Applications to Ridge2000 Science
NASA Astrophysics Data System (ADS)
Mayer, L.; Rzhanov, Y.; Fornari, D. J.; Soule, A.; Shank, T. M.; Beaulieu, S. E.; Schouten, H.; Tivey, M.
2004-12-01
Severe attenuation of visible light and limited power capabilities of many submersible vehicles require acquisition of imagery from short ranges, rarely exceeding 8-10 meters. Although modern video- and photo-equipment makes high-resolution video surveying possible, the field of view of each image remains relatively narrow. To compensate for the deficiencies in light and field of view researchers have been developing techniques allowing for combining images into larger composite images i.e., mosaicking. A properly constructed, accurate mosaic has a number of well-known advantages in comparison with the original sequence of images, the most notable being improved situational awareness. We have developed software strategies for PC-based computers that permit conversion of video imagery acquired from any underwater vehicle, operated within both absolute (e.g. LBL or USBL) or relative (e.g. Doppler Velocity Log-DVL) navigation networks, to quickly produce a set of geo-referenced photomosaics which can then be directly incorporated into a Geographic Information System (GIS) data base. The timescale of processing is rapid enough to permit analysis of the resulting mosaics between submersible dives thus enhancing the efficiency of deep-sea research. Commercial imaging processing packages usually handle cases where there is no or little parallax - an unlikely situation for undersea world where terrain has pronounced 3D content and imagery is acquired from moving platforms. The approach we have taken is optimized for situations in which there is significant relief and thus parallax in the imagery (e.g. seafloor fault scarps or constructional volcanic escarpments and flow fronts). The basis of all mosaicking techniques is a pair-wise image registration method that finds a transformation relating pixels of two consecutive image frames. We utilize a "rigid affine model" with four degrees of freedom for image registration that allows for camera translation in all directions and camera rotation about its optical axis. The coefficients of the transformation can be determined robustly using the well-established and powerful "featureless Fourier domain-based technique" (FFDT), which is an extension of the FFT-based correlation approach. While calculation of cross-correlation allows the recovery of only two parameters of the transformation (translation in 2D), FFDT uses the "Phase shift" theorem of the Fourier Transform as well as a log-polar transform of the Fourier magnitude spectrum to recover all four transformation coefficients required for the rigid affine model. Examples of results of our video mosaicking data processing for the East Pacific Rise ISS will be presented.
Video denoising using low rank tensor decomposition
NASA Astrophysics Data System (ADS)
Gui, Lihua; Cui, Gaochao; Zhao, Qibin; Wang, Dongsheng; Cichocki, Andrzej; Cao, Jianting
2017-03-01
Reducing noise in a video sequence is of vital important in many real-world applications. One popular method is block matching collaborative filtering. However, the main drawback of this method is that noise standard deviation for the whole video sequence is known in advance. In this paper, we present a tensor based denoising framework that considers 3D patches instead of 2D patches. By collecting the similar 3D patches non-locally, we employ the low-rank tensor decomposition for collaborative filtering. Since we specify the non-informative prior over the noise precision parameter, the noise variance can be inferred automatically from observed video data. Therefore, our method is more practical, which does not require knowing the noise variance. The experimental on video denoising demonstrates the effectiveness of our proposed method.
Multicore-based 3D-DWT video encoder
NASA Astrophysics Data System (ADS)
Galiano, Vicente; López-Granado, Otoniel; Malumbres, Manuel P.; Migallón, Hector
2013-12-01
Three-dimensional wavelet transform (3D-DWT) encoders are good candidates for applications like professional video editing, video surveillance, multi-spectral satellite imaging, etc. where a frame must be reconstructed as quickly as possible. In this paper, we present a new 3D-DWT video encoder based on a fast run-length coding engine. Furthermore, we present several multicore optimizations to speed-up the 3D-DWT computation. An exhaustive evaluation of the proposed encoder (3D-GOP-RL) has been performed, and we have compared the evaluation results with other video encoders in terms of rate/distortion (R/D), coding/decoding delay, and memory consumption. Results show that the proposed encoder obtains good R/D results for high-resolution video sequences with nearly in-place computation using only the memory needed to store a group of pictures. After applying the multicore optimization strategies over the 3D DWT, the proposed encoder is able to compress a full high-definition video sequence in real-time.
Characterizing popularity dynamics of online videos
NASA Astrophysics Data System (ADS)
Ren, Zhuo-Ming; Shi, Yu-Qiang; Liao, Hao
2016-07-01
Online popularity has a major impact on videos, music, news and other contexts in online systems. Characterizing online popularity dynamics is nature to explain the observed properties in terms of the already acquired popularity of each individual. In this paper, we provide a quantitative, large scale, temporal analysis of the popularity dynamics in two online video-provided websites, namely MovieLens and Netflix. The two collected data sets contain over 100 million records and even span a decade. We characterize that the popularity dynamics of online videos evolve over time, and find that the dynamics of the online video popularity can be characterized by the burst behaviors, typically occurring in the early life span of a video, and later restricting to the classic preferential popularity increase mechanism.
3D Reconstruction of Static Human Body with a Digital Camera
NASA Astrophysics Data System (ADS)
Remondino, Fabio
2003-01-01
Nowadays the interest in 3D reconstruction and modeling of real humans is one of the most challenging problems and a topic of great interest. The human models are used for movies, video games or ergonomics applications and they are usually created with 3D scanner devices. In this paper a new method to reconstruct the shape of a static human is presented. Our approach is based on photogrammetric techniques and uses a sequence of images acquired around a standing person with a digital still video camera or with a camcorder. First the images are calibrated and orientated using a bundle adjustment. After the establishment of a stable adjusted image block, an image matching process is performed between consecutive triplets of images. Finally the 3D coordinates of the matched points are computed with a mean accuracy of ca 2 mm by forward ray intersection. The obtained point cloud can then be triangulated to generate a surface model of the body or a virtual human model can be fitted to the recovered 3D data. Results of the 3D human point cloud with pixel color information are presented.
USDA-ARS?s Scientific Manuscript database
This record contains videos of apple trees acquired from a ground vehicle throughout the growing season at the USDA-ARS, Appalachian Fruit Research Station. Research in precision management methods in orchard crops revolve around locating objects of interest, namely flowers, fruitlets, and fruit, a...
NASA Technical Reports Server (NTRS)
Childers, Brooks A.; Snow, Walter L.
1990-01-01
Considerations for acquiring and analyzing 30 Hz video frames from charge coupled device (CCD) cameras mounted in the wing tips of a Beech T-34 aircraft are described. Particular attention is given to the characterization and correction of optical distortions inherent in the data.
Violent Video Games as Exemplary Teachers: A Conceptual Analysis
ERIC Educational Resources Information Center
Gentile, Douglas A.; Gentile, J. Ronald
2008-01-01
This article presents conceptual and empirical analyses of several of the "best practices" of learning and instruction, and demonstrates how violent video games use them effectively to motivate learners to persevere in acquiring and mastering a number of skills, to navigate through complex problems and changing environments, and to experiment with…
Teaching the blind to find their way by playing video games.
Merabet, Lotfi B; Connors, Erin C; Halko, Mark A; Sánchez, Jaime
2012-01-01
Computer based video games are receiving great interest as a means to learn and acquire new skills. As a novel approach to teaching navigation skills in the blind, we have developed Audio-based Environment Simulator (AbES); a virtual reality environment set within the context of a video game metaphor. Despite the fact that participants were naïve to the overall purpose of the software, we found that early blind users were able to acquire relevant information regarding the spatial layout of a previously unfamiliar building using audio based cues alone. This was confirmed by a series of behavioral performance tests designed to assess the transfer of acquired spatial information to a large-scale, real-world indoor navigation task. Furthermore, learning the spatial layout through a goal directed gaming strategy allowed for the mental manipulation of spatial information as evidenced by enhanced navigation performance when compared to an explicit route learning strategy. We conclude that the immersive and highly interactive nature of the software greatly engages the blind user to actively explore the virtual environment. This in turn generates an accurate sense of a large-scale three-dimensional space and facilitates the learning and transfer of navigation skills to the physical world.
Sanderson, Saskia C.; Suckiel, Sabrina A.; Zweig, Micol; Bottinger, Erwin P.; Jabs, Ethylin Wang; Richardson, Lynne D.
2016-01-01
Background: As whole-genome sequencing (WGS) increases in availability, WGS educational aids are needed for research participants, patients, and the general public. Our aim was therefore to develop an accessible and scalable WGS educational aid. Genet Med 18 5, 501–512. Methods: We engaged multiple stakeholders in an iterative process over a 1-year period culminating in the production of a novel 10-minute WGS educational animated video, “Whole Genome Sequencing and You” (https://goo.gl/HV8ezJ). We then presented the animated video to 281 online-survey respondents (the video-information group). There were also two comparison groups: a written-information group (n = 281) and a no-information group (n = 300). Genet Med 18 5, 501–512. Results: In the video-information group, 79% reported the video was easy to understand, satisfaction scores were high (mean 4.00 on 1–5 scale, where 5 = high satisfaction), and knowledge increased significantly. There were significant differences in knowledge compared with the no-information group but few differences compared with the written-information group. Intention to receive personal results from WGS and decisional conflict in response to a hypothetical scenario did not differ between the three groups. Genet Med 18 5, 501–512. Conclusions: The educational animated video, “Whole Genome Sequencing and You,” was well received by this sample of online-survey respondents. Further work is needed to evaluate its utility as an aid to informed decision making about WGS in other populations. Genet Med 18 5, 501–512. PMID:26334178
ERIC Educational Resources Information Center
Casinghino, Carl
2015-01-01
Teaching advanced video production is an art that requires great sensitivity to the process of providing feedback that helps students to learn and grow. Some students experience difficulty in developing narrative sequences or cause-and-effect strings of motion picture sequences. But when students learn to work collaboratively through the revision…
ERIC Educational Resources Information Center
Yakubova, Gulnoza; Hughes, Elizabeth M.; Shinaberry, Megan
2016-01-01
The purpose of this study was to determine the effectiveness of a video modeling intervention with concrete-representational-abstract instructional sequence in teaching mathematics concepts to students with autism spectrum disorder (ASD). A multiple baseline across skills design of single-case experimental methodology was used to determine the…
Collision count in rugby union: A comparison of micro-technology and video analysis methods.
Reardon, Cillian; Tobin, Daniel P; Tierney, Peter; Delahunt, Eamonn
2017-10-01
The aim of our study was to determine if there is a role for manipulation of g force thresholds acquired via micro-technology for accurately detecting collisions in rugby union. In total, 36 players were recruited from an elite Guinness Pro12 rugby union team. Player movement profiles and collisions were acquired via individual global positioning system (GPS) micro-technology units. Players were assigned to a sub-category of positions in order to determine positional collision demands. The coding of collisions by micro-technology at g force thresholds between 2 and 5.5 g (0.5 g increments) was compared with collision coding by an expert video analyst using Bland-Altman assessments. The most appropriate g force threshold (smallest mean difference compared with video analyst coding) was lower for all forwards positions (2.5 g) than for all backs positions (3.5 g). The Bland-Altman 95% limits of agreement indicated that there may be a substantial over- or underestimation of collisions coded via GPS micro-technology when using expert video analyst coding as the reference comparator. The manipulation of the g force thresholds applied to data acquired by GPS micro-technology units based on incremental thresholds of 0.5 g does not provide a reliable tool for the accurate coding of collisions in rugby union. Future research should aim to investigate smaller g force threshold increments and determine the events that cause coding of false positives.
ERIC Educational Resources Information Center
Scheflen, Sarah Clifford; Freeman, Stephanny F. N.; Paparella, Tanya
2012-01-01
Four children with autism were taught play skills through the use of video modeling. Video instruction was used to model play and appropriate language through a developmental sequence of play levels integrated with language techniques. Results showed that children with autism could successfully use video modeling to learn how to play appropriately…
Vierling, L.A.; Fersdahl, M.; Chen, X.; Li, Z.; Zimmerman, P.
2006-01-01
We describe a new remote sensing system called the Short Wave Aerostat-Mounted Imager (SWAMI). The SWAMI is designed to acquire co-located video imagery and hyperspectral data to study basic remote sensing questions and to link landscape level trace gas fluxes with spatially and temporally appropriate spectral observations. The SWAMI can fly at altitudes up to 2 km above ground level to bridge the spatial gap between radiometric measurements collected near the surface and those acquired by other aircraft or satellites. The SWAMI platform consists of a dual channel hyperspectral spectroradiometer, video camera, GPS, thermal infrared sensor, and several meteorological and control sensors. All SWAMI functions (e.g. data acquisition and sensor pointing) can be controlled from the ground via wireless transmission. Sample data from the sampling platform are presented, along with several potential scientific applications of SWAMI data.
An Effective Profile Based Video Browsing System for e-Learning
ERIC Educational Resources Information Center
Premaratne, S. C.; Karunaratna, D. D.; Hewagamage, K. P.
2007-01-01
E-learning has acquired a prime place in many discussions recently. A number of research efforts around the world are trying to enhance education and training through improving e-learning facilities. This paper briefly explains one such attempt aimed at designing a system to support video clips in e-learning and explains how profiles of the…
Lehmann, Ronny; Seitz, Anke; Bosse, Hans Martin; Lutz, Thomas; Huwendiek, Sören
2016-11-01
Physical examination skills are crucial for a medical doctor. The physical examination of children differs significantly from that of adults. Students often have only limited contact with pediatric patients to practice these skills. In order to improve the acquisition of pediatric physical examination skills during bedside teaching, we have developed a combined video-based training concept, subsequently evaluating its use and perception. Fifteen videos were compiled, demonstrating defined physical examination sequences in children of different ages. Students were encouraged to use these videos as preparation for bedside teaching during their pediatric clerkship. After bedside teaching, acceptance of this approach was evaluated using a 10-item survey, asking for the frequency of video use and the benefits to learning, self-confidence, and preparation of bedside teaching as well as the concluding OSCE. N=175 out of 299 students returned survey forms (58.5%). Students most frequently used videos, either illustrating complete examination sequences or corresponding focus examinations frequently assessed in the OSCE. Students perceived the videos as a helpful method of conveying the practical process and preparation for bedside teaching as well as the OSCE, and altogether considered them a worthwhile learning experience. Self-confidence at bedside teaching was enhanced by preparation with the videos. The demonstration of a defined standardized procedural sequence, explanatory comments, and demonstration of infrequent procedures and findings were perceived as particularly supportive. Long video segments, poor alignment with other curricular learning activities, and technical problems were perceived as less helpful. Students prefer an optional individual use of the videos, with easy technical access, thoughtful combination with the bedside teaching, and consecutive standardized practice of demonstrated procedures. Preparation with instructional videos combined with bedside teaching, were perceived to improve the acquisition of pediatric physical examination skills. Copyright © 2016 Elsevier GmbH. All rights reserved.
Cerina, Luca; Iozzia, Luca; Mainardi, Luca
2017-11-14
In this paper, common time- and frequency-domain variability indexes obtained by pulse rate variability (PRV) series extracted from video-photoplethysmographic signal (vPPG) were compared with heart rate variability (HRV) parameters calculated from synchronized ECG signals. The dual focus of this study was to analyze the effect of different video acquisition frame-rates starting from 60 frames-per-second (fps) down to 7.5 fps and different video compression techniques using both lossless and lossy codecs on PRV parameters estimation. Video recordings were acquired through an off-the-shelf GigE Sony XCG-C30C camera on 60 young, healthy subjects (age 23±4 years) in the supine position. A fully automated, signal extraction method based on the Kanade-Lucas-Tomasi (KLT) algorithm for regions of interest (ROI) detection and tracking, in combination with a zero-phase principal component analysis (ZCA) signal separation technique was employed to convert the video frames sequence to a pulsatile signal. The frame-rate degradation was simulated on video recordings by directly sub-sampling the ROI tracking and signal extraction modules, to correctly mimic videos recorded at a lower speed. The compression of the videos was configured to avoid any frame rejection caused by codec quality leveling, FFV1 codec was used for lossless compression and H.264 with variable quality parameter as lossy codec. The results showed that a reduced frame-rate leads to inaccurate tracking of ROIs, increased time-jitter in the signals dynamics and local peak displacements, which degrades the performances in all the PRV parameters. The root mean square of successive differences (RMSSD) and the proportion of successive differences greater than 50 ms (PNN50) indexes in time-domain and the low frequency (LF) and high frequency (HF) power in frequency domain were the parameters which highly degraded with frame-rate reduction. Such a degradation can be partially mitigated by up-sampling the measured signal at a higher frequency (namely 60 Hz). Concerning the video compression, the results showed that compression techniques are suitable for the storage of vPPG recordings, although lossless or intra-frame compression are to be preferred over inter-frame compression methods. FFV1 performances are very close to the uncompressed (UNC) version with less than 45% disk size. H.264 showed a degradation of the PRV estimation directly correlated with the increase of the compression ratio.
Video image stabilization and registration--plus
NASA Technical Reports Server (NTRS)
Hathaway, David H. (Inventor)
2009-01-01
A method of stabilizing a video image displayed in multiple video fields of a video sequence includes the steps of: subdividing a selected area of a first video field into nested pixel blocks; determining horizontal and vertical translation of each of the pixel blocks in each of the pixel block subdivision levels from the first video field to a second video field; and determining translation of the image from the first video field to the second video field by determining a change in magnification of the image from the first video field to the second video field in each of horizontal and vertical directions, and determining shear of the image from the first video field to the second video field in each of the horizontal and vertical directions.
The emerging High Efficiency Video Coding standard (HEVC)
NASA Astrophysics Data System (ADS)
Raja, Gulistan; Khan, Awais
2013-12-01
High definition video (HDV) is becoming popular day by day. This paper describes the performance analysis of latest upcoming video standard known as High Efficiency Video Coding (HEVC). HEVC is designed to fulfil all the requirements for future high definition videos. In this paper, three configurations (intra only, low delay and random access) of HEVC are analyzed using various 480p, 720p and 1080p high definition test video sequences. Simulation results show the superior objective and subjective quality of HEVC.
Moving object detection and tracking in videos through turbulent medium
NASA Astrophysics Data System (ADS)
Halder, Kalyan Kumar; Tahtali, Murat; Anavatti, Sreenatha G.
2016-06-01
This paper addresses the problem of identifying and tracking moving objects in a video sequence having a time-varying background. This is a fundamental task in many computer vision applications, though a very challenging one because of turbulence that causes blurring and spatiotemporal movements of the background images. Our proposed approach involves two major steps. First, a moving object detection algorithm that deals with the detection of real motions by separating the turbulence-induced motions using a two-level thresholding technique is used. In the second step, a feature-based generalized regression neural network is applied to track the detected objects throughout the frames in the video sequence. The proposed approach uses the centroid and area features of the moving objects and creates the reference regions instantly by selecting the objects within a circle. Simulation experiments are carried out on several turbulence-degraded video sequences and comparisons with an earlier method confirms that the proposed approach provides a more effective tracking of the targets.
Effects of blurring and vertical misalignment on visual fatigue of stereoscopic displays
NASA Astrophysics Data System (ADS)
Baek, Sangwook; Lee, Chulhee
2015-03-01
In this paper, we investigate two error issues in stereo images, which may produce visual fatigue. When two cameras are used to produce 3D video sequences, vertical misalignment can be a problem. Although this problem may not occur in professionally produced 3D programs, it is still a major issue in many low-cost 3D programs. Recently, efforts have been made to produce 3D video programs using smart phones or tablets, which may present the vertical alignment problem. Also, in 2D-3D conversion techniques, the simulated frame may have blur effects, which can also introduce visual fatigue in 3D programs. In this paper, to investigate the relationship between these two errors (vertical misalignment and blurring in one image), we performed a subjective test using simulated 3D video sequences that include stereo video sequences with various vertical misalignments and blurring in a stereo image. We present some analyses along with objective models to predict the degree of visual fatigue from vertical misalignment and blurring.
Content-based video retrieval by example video clip
NASA Astrophysics Data System (ADS)
Dimitrova, Nevenka; Abdel-Mottaleb, Mohamed
1997-01-01
This paper presents a novel approach for video retrieval from a large archive of MPEG or Motion JPEG compressed video clips. We introduce a retrieval algorithm that takes a video clip as a query and searches the database for clips with similar contents. Video clips are characterized by a sequence of representative frame signatures, which are constructed from DC coefficients and motion information (`DC+M' signatures). The similarity between two video clips is determined by using their respective signatures. This method facilitates retrieval of clips for the purpose of video editing, broadcast news retrieval, or copyright violation detection.
Using Video Modeling to Teach Complex Social Sequences to Children with Autism
ERIC Educational Resources Information Center
Nikopoulos, Christos K.; Keenan, Mickey
2007-01-01
This study comprised of two experiments was designed to teach complex social sequences to children with autism. Experimental control was achieved by collecting data using means of within-system design methodology. Across a number of conditions children were taken to a room to view one of the four short videos of two people engaging in a simple…
Digital readout for image converter cameras
NASA Astrophysics Data System (ADS)
Honour, Joseph
1991-04-01
There is an increasing need for fast and reliable analysis of recorded sequences from image converter cameras so that experimental information can be readily evaluated without recourse to more time consuming photographic procedures. A digital readout system has been developed using a randomly triggerable high resolution CCD camera, the output of which is suitable for use with IBM AT compatible PC. Within half a second from receipt of trigger pulse, the frame reformatter displays the image and transfer to storage media can be readily achieved via the PC and dedicated software. Two software programmes offer different levels of image manipulation which includes enhancement routines and parameter calculations with accuracy down to pixel levels. Hard copy prints can be acquired using a specially adapted Polaroid printer, outputs for laser and video printer extend the overall versatility of the system.
Source-Adaptation-Based Wireless Video Transport: A Cross-Layer Approach
NASA Astrophysics Data System (ADS)
Qu, Qi; Pei, Yong; Modestino, James W.; Tian, Xusheng
2006-12-01
Real-time packet video transmission over wireless networks is expected to experience bursty packet losses that can cause substantial degradation to the transmitted video quality. In wireless networks, channel state information is hard to obtain in a reliable and timely manner due to the rapid change of wireless environments. However, the source motion information is always available and can be obtained easily and accurately from video sequences. Therefore, in this paper, we propose a novel cross-layer framework that exploits only the motion information inherent in video sequences and efficiently combines a packetization scheme, a cross-layer forward error correction (FEC)-based unequal error protection (UEP) scheme, an intracoding rate selection scheme as well as a novel intraframe interleaving scheme. Our objective and subjective results demonstrate that the proposed approach is very effective in dealing with the bursty packet losses occurring on wireless networks without incurring any additional implementation complexity or delay. Thus, the simplicity of our proposed system has important implications for the implementation of a practical real-time video transmission system.
Visual Attention Modeling for Stereoscopic Video: A Benchmark and Computational Model.
Fang, Yuming; Zhang, Chi; Li, Jing; Lei, Jianjun; Perreira Da Silva, Matthieu; Le Callet, Patrick
2017-10-01
In this paper, we investigate the visual attention modeling for stereoscopic video from the following two aspects. First, we build one large-scale eye tracking database as the benchmark of visual attention modeling for stereoscopic video. The database includes 47 video sequences and their corresponding eye fixation data. Second, we propose a novel computational model of visual attention for stereoscopic video based on Gestalt theory. In the proposed model, we extract the low-level features, including luminance, color, texture, and depth, from discrete cosine transform coefficients, which are used to calculate feature contrast for the spatial saliency computation. The temporal saliency is calculated by the motion contrast from the planar and depth motion features in the stereoscopic video sequences. The final saliency is estimated by fusing the spatial and temporal saliency with uncertainty weighting, which is estimated by the laws of proximity, continuity, and common fate in Gestalt theory. Experimental results show that the proposed method outperforms the state-of-the-art stereoscopic video saliency detection models on our built large-scale eye tracking database and one other database (DML-ITRACK-3D).
Digital video steganalysis exploiting collusion sensitivity
NASA Astrophysics Data System (ADS)
Budhia, Udit; Kundur, Deepa
2004-09-01
In this paper we present an effective steganalyis technique for digital video sequences based on the collusion attack. Steganalysis is the process of detecting with a high probability and low complexity the presence of covert data in multimedia. Existing algorithms for steganalysis target detecting covert information in still images. When applied directly to video sequences these approaches are suboptimal. In this paper, we present a method that overcomes this limitation by using redundant information present in the temporal domain to detect covert messages in the form of Gaussian watermarks. Our gains are achieved by exploiting the collusion attack that has recently been studied in the field of digital video watermarking, and more sophisticated pattern recognition tools. Applications of our scheme include cybersecurity and cyberforensics.
Trends in Video Game Play through Childhood, Adolescence, and Emerging Adulthood
Ream, Geoffrey L.; Elliott, Luther C.; Dunlap, Eloise
2013-01-01
This study explored the relationship between video gaming and age during childhood, adolescence, and emerging adulthood. It also examined whether “role incompatibility,” the theory that normative levels of substance use decrease through young adulthood as newly acquired adult roles create competing demands, generalizes to video gaming. Emerging adult video gamers (n = 702) recruited from video gaming contexts in New York City completed a computer-assisted personal interview and life-history calendar. All four video gaming indicators—days/week played, school/work day play, nonschool/work day play, and problem play—had significant curvilinear relationships with age. The “shape” of video gaming's relationship with age is, therefore, similar to that of substance use, but video gaming appears to peak earlier in life than substance use, that is, in late adolescence rather than emerging adulthood. Of the four video gaming indicators, role incompatibility only significantly affected school/work day play, the dimension with the clearest potential to interfere with life obligations. PMID:24236277
Video Kills the Lecturing Star: New Technologies and the Teaching of Meterology.
ERIC Educational Resources Information Center
Sumner, Graham
1984-01-01
The educational potential of time-lapse video sequences and weather data obtained using a conventional microcomputer are considered in the light of recent advances in both fields. Illustrates how videos and microcomputers can be used to study clouds in meteorology classes. (RM)
NASA Astrophysics Data System (ADS)
Barnett, Barry S.; Bovik, Alan C.
1995-04-01
This paper presents a real time full motion video conferencing system based on the Visual Pattern Image Sequence Coding (VPISC) software codec. The prototype system hardware is comprised of two personal computers, two camcorders, two frame grabbers, and an ethernet connection. The prototype system software has a simple structure. It runs under the Disk Operating System, and includes a user interface, a video I/O interface, an event driven network interface, and a free running or frame synchronous video codec that also acts as the controller for the video and network interfaces. Two video coders have been tested in this system. Simple implementations of Visual Pattern Image Coding and VPISC have both proven to support full motion video conferencing with good visual quality. Future work will concentrate on expanding this prototype to support the motion compensated version of VPISC, as well as encompassing point-to-point modem I/O and multiple network protocols. The application will be ported to multiple hardware platforms and operating systems. The motivation for developing this prototype system is to demonstrate the practicality of software based real time video codecs. Furthermore, software video codecs are not only cheaper, but are more flexible system solutions because they enable different computer platforms to exchange encoded video information without requiring on-board protocol compatible video codex hardware. Software based solutions enable true low cost video conferencing that fits the `open systems' model of interoperability that is so important for building portable hardware and software applications.
Using Video Prompting to Teach Cooking Skills to Secondary Students with Moderate Disabilities
ERIC Educational Resources Information Center
Graves, Tara B.; Collins, Belva C.; Schuster, John W.; Kleinert, Harold
2005-01-01
Three secondary students with moderate disabilities acquired cooking skills through a constant time delay procedure used with video prompting. A multiple probe design was used to evaluate effectiveness of the procedure to teach preparation of a food item (a) on a stove, (b) in a microwave, and (c) on a counter top. The procedure was effective for…
Teaching the Blind to Find Their Way by Playing Video Games
Merabet, Lotfi B.; Connors, Erin C.; Halko, Mark A.; Sánchez, Jaime
2012-01-01
Computer based video games are receiving great interest as a means to learn and acquire new skills. As a novel approach to teaching navigation skills in the blind, we have developed Audio-based Environment Simulator (AbES); a virtual reality environment set within the context of a video game metaphor. Despite the fact that participants were naïve to the overall purpose of the software, we found that early blind users were able to acquire relevant information regarding the spatial layout of a previously unfamiliar building using audio based cues alone. This was confirmed by a series of behavioral performance tests designed to assess the transfer of acquired spatial information to a large-scale, real-world indoor navigation task. Furthermore, learning the spatial layout through a goal directed gaming strategy allowed for the mental manipulation of spatial information as evidenced by enhanced navigation performance when compared to an explicit route learning strategy. We conclude that the immersive and highly interactive nature of the software greatly engages the blind user to actively explore the virtual environment. This in turn generates an accurate sense of a large-scale three-dimensional space and facilitates the learning and transfer of navigation skills to the physical world. PMID:23028703
Subjective quality evaluation of low-bit-rate video
NASA Astrophysics Data System (ADS)
Masry, Mark; Hemami, Sheila S.; Osberger, Wilfried M.; Rohaly, Ann M.
2001-06-01
A subjective quality evaluation was performed to qualify vie4wre responses to visual defects that appear in low bit rate video at full and reduced frame rates. The stimuli were eight sequences compressed by three motion compensated encoders - Sorenson Video, H.263+ and a Wavelet based coder - operating at five bit/frame rate combinations. The stimulus sequences exhibited obvious coding artifacts whose nature differed across the three coders. The subjective evaluation was performed using the Single Stimulus Continuos Quality Evaluation method of UTI-R Rec. BT.500-8. Viewers watched concatenated coded test sequences and continuously registered the perceived quality using a slider device. Data form 19 viewers was colleted. An analysis of their responses to the presence of various artifacts across the range of possible coding conditions and content is presented. The effects of blockiness and blurriness on perceived quality are examined. The effects of changes in frame rate on perceived quality are found to be related to the nature of the motion in the sequence.
Heterogeneity image patch index and its application to consumer video summarization.
Dang, Chinh T; Radha, Hayder
2014-06-01
Automatic video summarization is indispensable for fast browsing and efficient management of large video libraries. In this paper, we introduce an image feature that we refer to as heterogeneity image patch (HIP) index. The proposed HIP index provides a new entropy-based measure of the heterogeneity of patches within any picture. By evaluating this index for every frame in a video sequence, we generate a HIP curve for that sequence. We exploit the HIP curve in solving two categories of video summarization applications: key frame extraction and dynamic video skimming. Under the key frame extraction frame-work, a set of candidate key frames is selected from abundant video frames based on the HIP curve. Then, a proposed patch-based image dissimilarity measure is used to create affinity matrix of these candidates. Finally, a set of key frames is extracted from the affinity matrix using a min–max based algorithm. Under video skimming, we propose a method to measure the distance between a video and its skimmed representation. The video skimming problem is then mapped into an optimization framework and solved by minimizing a HIP-based distance for a set of extracted excerpts. The HIP framework is pixel-based and does not require semantic information or complex camera motion estimation. Our simulation results are based on experiments performed on consumer videos and are compared with state-of-the-art methods. It is shown that the HIP approach outperforms other leading methods, while maintaining low complexity.
ERIC Educational Resources Information Center
Celis Nova, Jonnathan; Onatra Chavarro, Clara Isabel; Zubieta Córdoba, Any Tatiana
2017-01-01
The following paper seeks to develop a proposal, observing to what extent educational videos and affective learning can strengthen vocabulary in an EFL setting. This action research study was done with fifth grade students belonging to a public school, who showed a low degree of motivation in the English class, making it difficult to acquire the…
Onboard Systems Record Unique Videos of Space Missions
NASA Technical Reports Server (NTRS)
2010-01-01
Ecliptic Enterprises Corporation, headquartered in Pasadena, California, provided onboard video systems for rocket and space shuttle launches before it was tasked by Ames Research Center to craft the Data Handling Unit that would control sensor instruments onboard the Lunar Crater Observation and Sensing Satellite (LCROSS) spacecraft. The technological capabilities the company acquired on this project, as well as those gained developing a high-speed video system for monitoring the parachute deployments for the Orion Pad Abort Test Program at Dryden Flight Research Center, have enabled the company to offer high-speed and high-definition video for geosynchronous satellites and commercial space missions, providing remarkable footage that both informs engineers and inspires the imagination of the general public.
Robust video super-resolution with registration efficiency adaptation
NASA Astrophysics Data System (ADS)
Zhang, Xinfeng; Xiong, Ruiqin; Ma, Siwei; Zhang, Li; Gao, Wen
2010-07-01
Super-Resolution (SR) is a technique to construct a high-resolution (HR) frame by fusing a group of low-resolution (LR) frames describing the same scene. The effectiveness of the conventional super-resolution techniques, when applied on video sequences, strongly relies on the efficiency of motion alignment achieved by image registration. Unfortunately, such efficiency is limited by the motion complexity in the video and the capability of adopted motion model. In image regions with severe registration errors, annoying artifacts usually appear in the produced super-resolution video. This paper proposes a robust video super-resolution technique that adapts itself to the spatially-varying registration efficiency. The reliability of each reference pixel is measured by the corresponding registration error and incorporated into the optimization objective function of SR reconstruction. This makes the SR reconstruction highly immune to the registration errors, as outliers with higher registration errors are assigned lower weights in the objective function. In particular, we carefully design a mechanism to assign weights according to registration errors. The proposed superresolution scheme has been tested with various video sequences and experimental results clearly demonstrate the effectiveness of the proposed method.
NASA Astrophysics Data System (ADS)
Boumehrez, Farouk; Brai, Radhia; Doghmane, Noureddine; Mansouri, Khaled
2018-01-01
Recently, video streaming has attracted much attention and interest due to its capability to process and transmit large data. We propose a quality of experience (QoE) model relying on high efficiency video coding (HEVC) encoder adaptation scheme, in turn based on the multiple description coding (MDC) for video streaming. The main contributions of the paper are (1) a performance evaluation of the new and emerging video coding standard HEVC/H.265, which is based on the variation of quantization parameter (QP) values depending on different video contents to deduce their influence on the sequence to be transmitted, (2) QoE support multimedia applications in wireless networks are investigated, so we inspect the packet loss impact on the QoE of transmitted video sequences, (3) HEVC encoder parameter adaptation scheme based on MDC is modeled with the encoder parameter and objective QoE model. A comparative study revealed that the proposed MDC approach is effective for improving the transmission with a peak signal-to-noise ratio (PSNR) gain of about 2 to 3 dB. Results show that a good choice of QP value can compensate for transmission channel effects and improve received video quality, although HEVC/H.265 is also sensitive to packet loss. The obtained results show the efficiency of our proposed method in terms of PSNR and mean-opinion-score.
Dual-Layer Video Encryption using RSA Algorithm
NASA Astrophysics Data System (ADS)
Chadha, Aman; Mallik, Sushmit; Chadha, Ankit; Johar, Ravdeep; Mani Roja, M.
2015-04-01
This paper proposes a video encryption algorithm using RSA and Pseudo Noise (PN) sequence, aimed at applications requiring sensitive video information transfers. The system is primarily designed to work with files encoded using the Audio Video Interleaved (AVI) codec, although it can be easily ported for use with Moving Picture Experts Group (MPEG) encoded files. The audio and video components of the source separately undergo two layers of encryption to ensure a reasonable level of security. Encryption of the video component involves applying the RSA algorithm followed by the PN-based encryption. Similarly, the audio component is first encrypted using PN and further subjected to encryption using the Discrete Cosine Transform. Combining these techniques, an efficient system, invulnerable to security breaches and attacks with favorable values of parameters such as encryption/decryption speed, encryption/decryption ratio and visual degradation; has been put forth. For applications requiring encryption of sensitive data wherein stringent security requirements are of prime concern, the system is found to yield negligible similarities in visual perception between the original and the encrypted video sequence. For applications wherein visual similarity is not of major concern, we limit the encryption task to a single level of encryption which is accomplished by using RSA, thereby quickening the encryption process. Although some similarity between the original and encrypted video is observed in this case, it is not enough to comprehend the happenings in the video.
High-Definition Television (HDTV) Images for Earth Observations and Earth Science Applications
NASA Technical Reports Server (NTRS)
Robinson, Julie A.; Holland, S. Douglas; Runco, Susan K.; Pitts, David E.; Whitehead, Victor S.; Andrefouet, Serge M.
2000-01-01
As part of Detailed Test Objective 700-17A, astronauts acquired Earth observation images from orbit using a high-definition television (HDTV) camcorder, Here we provide a summary of qualitative findings following completion of tests during missions STS (Space Transport System)-93 and STS-99. We compared HDTV imagery stills to images taken using payload bay video cameras, Hasselblad film camera, and electronic still camera. We also evaluated the potential for motion video observations of changes in sunlight and the use of multi-aspect viewing to image aerosols. Spatial resolution and color quality are far superior in HDTV images compared to National Television Systems Committee (NTSC) video images. Thus, HDTV provides the first viable option for video-based remote sensing observations of Earth from orbit. Although under ideal conditions, HDTV images have less spatial resolution than medium-format film cameras, such as the Hasselblad, under some conditions on orbit, the HDTV image acquired compared favorably with the Hasselblad. Of particular note was the quality of color reproduction in the HDTV images HDTV and electronic still camera (ESC) were not compared with matched fields of view, and so spatial resolution could not be compared for the two image types. However, the color reproduction of the HDTV stills was truer than colors in the ESC images. As HDTV becomes the operational video standard for Space Shuttle and Space Station, HDTV has great potential as a source of Earth-observation data. Planning for the conversion from NTSC to HDTV video standards should include planning for Earth data archiving and distribution.
Thin-slice vision: inference of confidence measure from perceptual video quality
NASA Astrophysics Data System (ADS)
Hameed, Abdul; Balas, Benjamin; Dai, Rui
2016-11-01
There has been considerable research on thin-slice judgments, but no study has demonstrated the predictive validity of confidence measures when assessors watch videos acquired from communication systems, in which the perceptual quality of videos could be degraded by limited bandwidth and unreliable network conditions. This paper studies the relationship between high-level thin-slice judgments of human behavior and factors that contribute to perceptual video quality. Based on a large number of subjective test results, it has been found that the confidence of a single individual present in all the videos, called speaker's confidence (SC), could be predicted by a list of features that contribute to perceptual video quality. Two prediction models, one based on artificial neural network and the other based on a decision tree, were built to predict SC. Experimental results have shown that both prediction models can result in high correlation measures.
Video games and surgical ability: a literature review.
Lynch, Jeremy; Aughwane, Paul; Hammond, Toby M
2010-01-01
Surgical training is rapidly evolving because of reduced training hours and the reduction of training opportunities due to patient safety concerns. There is a popular conception that video game usage might be linked to improved operating ability especially those techniques involving endoscopic modalities. If true this might suggest future directions for training. A search was made of the MEDLINE databases for the MeSH term, "Video Games," combined with the terms "Surgical Procedures, Operative," "Endoscopy," "Robotics," "Education," "Learning," "Simulators," "Computer Simulation," "Psychomotor Performance," and "Surgery, Computer-Assisted,"encompassing all journal articles before November 2009. References of articles were searched for further studies. Twelve relevant journal articles were discovered. Video game usage has been studied in relationship to laparoscopic, gastrointestinal endoscopic, endovascular, and robotic surgery. Video game users acquire endoscopic but not robotic techniques quicker, and training on video games appears to improve performance. Copyright (c) 2010 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Pande, Paritosh; Shelton, Ryan L; Monroy, Guillermo L; Nolan, Ryan M; Boppart, Stephen A
2016-10-01
The thickness of the human tympanic membrane (TM) is known to vary considerably across different regions of the TM. Quantitative determination of the thickness distribution and mapping of the TM is of significant importance in hearing research, particularly in mathematical modeling of middle-ear dynamics. Change in TM thickness is also associated with several middle-ear pathologies. Determination of the TM thickness distribution could therefore also enable a more comprehensive diagnosis of various otologic diseases. Despite its importance, very limited data on human TM thickness distribution, obtained almost exclusively from ex vivo samples, are available in the literature. In this study, the thickness distribution for the in vivo human TM is reported for the first time. A hand-held imaging system, which combines a low coherence interferometry (LCI) technique for single-point thickness measurement, with video-otoscopy for recording the image of the TM, was used to collect the data used in this study. Data were acquired by pointing the imaging probe over different regions of the TM, while simultaneously recording the LCI and concomitant TM surface video image data from an average of 500 locations on the TM. TM thickness distribution maps were obtained by mapping the LCI imaging sites onto an anatomically accurate wide-field image of the TM, which was generated by mosaicking the sequence of multiple small field-of-view video-otoscopy images. Descriptive statistics of the thickness measurements obtained from the different regions of the TM are presented, and the general thickness distribution trends are discussed.
BNU-LSVED: a multimodal spontaneous expression database in educational environment
NASA Astrophysics Data System (ADS)
Sun, Bo; Wei, Qinglan; He, Jun; Yu, Lejun; Zhu, Xiaoming
2016-09-01
In the field of pedagogy or educational psychology, emotions are treated as very important factors, which are closely associated with cognitive processes. Hence, it is meaningful for teachers to analyze students' emotions in classrooms, thus adjusting their teaching activities and improving students ' individual development. To provide a benchmark for different expression recognition algorithms, a large collection of training and test data in classroom environment has become an acute problem that needs to be resolved. In this paper, we present a multimodal spontaneous database in real learning environment. To collect the data, students watched seven kinds of teaching videos and were simultaneously filmed by a camera. Trained coders made one of the five learning expression labels for each image sequence extracted from the captured videos. This subset consists of 554 multimodal spontaneous expression image sequences (22,160 frames) recorded in real classrooms. There are four main advantages in this database. 1) Due to recorded in the real classroom environment, viewer's distance from the camera and the lighting of the database varies considerably between image sequences. 2) All the data presented are natural spontaneous responses to teaching videos. 3) The multimodal database also contains nonverbal behavior including eye movement, head posture and gestures to infer a student ' s affective state during the courses. 4) In the video sequences, there are different kinds of temporal activation patterns. In addition, we have demonstrated the labels for the image sequences are in high reliability through Cronbach's alpha method.
Dual Temporal Scale Convolutional Neural Network for Micro-Expression Recognition.
Peng, Min; Wang, Chongyang; Chen, Tong; Liu, Guangyuan; Fu, Xiaolan
2017-01-01
Facial micro-expression is a brief involuntary facial movement and can reveal the genuine emotion that people try to conceal. Traditional methods of spontaneous micro-expression recognition rely excessively on sophisticated hand-crafted feature design and the recognition rate is not high enough for its practical application. In this paper, we proposed a Dual Temporal Scale Convolutional Neural Network (DTSCNN) for spontaneous micro-expressions recognition. The DTSCNN is a two-stream network. Different of stream of DTSCNN is used to adapt to different frame rate of micro-expression video clips. Each stream of DSTCNN consists of independent shallow network for avoiding the overfitting problem. Meanwhile, we fed the networks with optical-flow sequences to ensure that the shallow networks can further acquire higher-level features. Experimental results on spontaneous micro-expression databases (CASME I/II) showed that our method can achieve a recognition rate almost 10% higher than what some state-of-the-art method can achieve.
A novel multiple description scalable coding scheme for mobile wireless video transmission
NASA Astrophysics Data System (ADS)
Zheng, Haifeng; Yu, Lun; Chen, Chang Wen
2005-03-01
We proposed in this paper a novel multiple description scalable coding (MDSC) scheme based on in-band motion compensation temporal filtering (IBMCTF) technique in order to achieve high video coding performance and robust video transmission. The input video sequence is first split into equal-sized groups of frames (GOFs). Within a GOF, each frame is hierarchically decomposed by discrete wavelet transform. Since there is a direct relationship between wavelet coefficients and what they represent in the image content after wavelet decomposition, we are able to reorganize the spatial orientation trees to generate multiple bit-streams and employed SPIHT algorithm to achieve high coding efficiency. We have shown that multiple bit-stream transmission is very effective in combating error propagation in both Internet video streaming and mobile wireless video. Furthermore, we adopt the IBMCTF scheme to remove the redundancy for inter-frames along the temporal direction using motion compensated temporal filtering, thus high coding performance and flexible scalability can be provided in this scheme. In order to make compressed video resilient to channel error and to guarantee robust video transmission over mobile wireless channels, we add redundancy to each bit-stream and apply error concealment strategy for lost motion vectors. Unlike traditional multiple description schemes, the integration of these techniques enable us to generate more than two bit-streams that may be more appropriate for multiple antenna transmission of compressed video. Simulate results on standard video sequences have shown that the proposed scheme provides flexible tradeoff between coding efficiency and error resilience.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lupinetti, F.
1988-01-01
This paper outlines a video communication system capable of non-line-of-sight (NLOS), secure, low-probability of intercept (LPI), antijam, real time transmission and reception of video information in a tactical enviroment. An introduction to a class of ternary PN sequences is presented to familiarize the reader with yet another avenue for spreading and despreading baseband information. The use of the high frequency (HF) band (1.5 to 30 MHz) for real time video transmission is suggested to allow NLOS communication. The spreading of the baseband information by means of multiple nontrivially different ternary pseudonoise (PN) sequence is used in order to assure encryptionmore » of the signal, enhanced security, a good degree of LPI, and good antijam features. 18 refs., 3 figs., 1 tab.« less
Video Denoising via Dynamic Video Layering
NASA Astrophysics Data System (ADS)
Guo, Han; Vaswani, Namrata
2018-07-01
Video denoising refers to the problem of removing "noise" from a video sequence. Here the term "noise" is used in a broad sense to refer to any corruption or outlier or interference that is not the quantity of interest. In this work, we develop a novel approach to video denoising that is based on the idea that many noisy or corrupted videos can be split into three parts - the "low-rank layer", the "sparse layer", and a small residual (which is small and bounded). We show, using extensive experiments, that our denoising approach outperforms the state-of-the-art denoising algorithms.
Compression of computer generated phase-shifting hologram sequence using AVC and HEVC
NASA Astrophysics Data System (ADS)
Xing, Yafei; Pesquet-Popescu, Béatrice; Dufaux, Frederic
2013-09-01
With the capability of achieving twice the compression ratio of Advanced Video Coding (AVC) with similar reconstruction quality, High Efficiency Video Coding (HEVC) is expected to become the newleading technique of video coding. In order to reduce the storage and transmission burden of digital holograms, in this paper we propose to use HEVC for compressing the phase-shifting digital hologram sequences (PSDHS). By simulating phase-shifting digital holography (PSDH) interferometry, interference patterns between illuminated three dimensional( 3D) virtual objects and the stepwise phase changed reference wave are generated as digital holograms. The hologram sequences are obtained by the movement of the virtual objects and compressed by AVC and HEVC. The experimental results show that AVC and HEVC are efficient to compress PSDHS, with HEVC giving better performance. Good compression rate and reconstruction quality can be obtained with bitrate above 15000kbps.
Human action classification using procrustes shape theory
NASA Astrophysics Data System (ADS)
Cho, Wanhyun; Kim, Sangkyoon; Park, Soonyoung; Lee, Myungeun
2015-02-01
In this paper, we propose new method that can classify a human action using Procrustes shape theory. First, we extract a pre-shape configuration vector of landmarks from each frame of an image sequence representing an arbitrary human action, and then we have derived the Procrustes fit vector for pre-shape configuration vector. Second, we extract a set of pre-shape vectors from tanning sample stored at database, and we compute a Procrustes mean shape vector for these preshape vectors. Third, we extract a sequence of the pre-shape vectors from input video, and we project this sequence of pre-shape vectors on the tangent space with respect to the pole taking as a sequence of mean shape vectors corresponding with a target video. And we calculate the Procrustes distance between two sequences of the projection pre-shape vectors on the tangent space and the mean shape vectors. Finally, we classify the input video into the human action class with minimum Procrustes distance. We assess a performance of the proposed method using one public dataset, namely Weizmann human action dataset. Experimental results reveal that the proposed method performs very good on this dataset.
Pre-processing SAR image stream to facilitate compression for transport on bandwidth-limited-link
Rush, Bobby G.; Riley, Robert
2015-09-29
Pre-processing is applied to a raw VideoSAR (or similar near-video rate) product to transform the image frame sequence into a product that resembles more closely the type of product for which conventional video codecs are designed, while sufficiently maintaining utility and visual quality of the product delivered by the codec.
Real-time image sequence segmentation using curve evolution
NASA Astrophysics Data System (ADS)
Zhang, Jun; Liu, Weisong
2001-04-01
In this paper, we describe a novel approach to image sequence segmentation and its real-time implementation. This approach uses the 3D structure tensor to produce a more robust frame difference signal and uses curve evolution to extract whole objects. Our algorithm is implemented on a standard PC running the Windows operating system with video capture from a USB camera that is a standard Windows video capture device. Using the Windows standard video I/O functionalities, our segmentation software is highly portable and easy to maintain and upgrade. In its current implementation on a Pentium 400, the system can perform segmentation at 5 frames/sec with a frame resolution of 160 by 120.
Video Salient Object Detection via Fully Convolutional Networks.
Wang, Wenguan; Shen, Jianbing; Shao, Ling
This paper proposes a deep learning model to efficiently detect salient regions in videos. It addresses two important issues: 1) deep video saliency model training with the absence of sufficiently large and pixel-wise annotated video data and 2) fast video saliency training and detection. The proposed deep video saliency network consists of two modules, for capturing the spatial and temporal saliency information, respectively. The dynamic saliency model, explicitly incorporating saliency estimates from the static saliency model, directly produces spatiotemporal saliency inference without time-consuming optical flow computation. We further propose a novel data augmentation technique that simulates video training data from existing annotated image data sets, which enables our network to learn diverse saliency information and prevents overfitting with the limited number of training videos. Leveraging our synthetic video data (150K video sequences) and real videos, our deep video saliency model successfully learns both spatial and temporal saliency cues, thus producing accurate spatiotemporal saliency estimate. We advance the state-of-the-art on the densely annotated video segmentation data set (MAE of .06) and the Freiburg-Berkeley Motion Segmentation data set (MAE of .07), and do so with much improved speed (2 fps with all steps).This paper proposes a deep learning model to efficiently detect salient regions in videos. It addresses two important issues: 1) deep video saliency model training with the absence of sufficiently large and pixel-wise annotated video data and 2) fast video saliency training and detection. The proposed deep video saliency network consists of two modules, for capturing the spatial and temporal saliency information, respectively. The dynamic saliency model, explicitly incorporating saliency estimates from the static saliency model, directly produces spatiotemporal saliency inference without time-consuming optical flow computation. We further propose a novel data augmentation technique that simulates video training data from existing annotated image data sets, which enables our network to learn diverse saliency information and prevents overfitting with the limited number of training videos. Leveraging our synthetic video data (150K video sequences) and real videos, our deep video saliency model successfully learns both spatial and temporal saliency cues, thus producing accurate spatiotemporal saliency estimate. We advance the state-of-the-art on the densely annotated video segmentation data set (MAE of .06) and the Freiburg-Berkeley Motion Segmentation data set (MAE of .07), and do so with much improved speed (2 fps with all steps).
A teledentistry system for the second opinion.
Gambino, Orazio; Lima, Fausto; Pirrone, Roberto; Ardizzone, Edoardo; Campisi, Giuseppina; di Fede, Olga
2014-01-01
In this paper we present a Teledentistry system aimed to the Second Opinion task. It make use of a particular camera called intra-oral camera, also called dental camera, in order to perform the photo shooting and real-time video of the inner part of the mouth. The pictures acquired by the Operator with such a device are sent to the Oral Medicine Expert (OME) by means of a current File Transfer Protocol (FTP) service and the real-time video is channeled into a video streaming thanks to the VideoLan client/server (VLC) application. It is composed by a HTML5 web-pages generated by PHP and allows to perform the Second Opinion both when Operator and OME are logged and when one of them is offline.
Extraction of Blebs in Human Embryonic Stem Cell Videos.
Guan, Benjamin X; Bhanu, Bir; Talbot, Prue; Weng, Nikki Jo-Hao
2016-01-01
Blebbing is an important biological indicator in determining the health of human embryonic stem cells (hESC). Especially, areas of a bleb sequence in a video are often used to distinguish two cell blebbing behaviors in hESC: dynamic and apoptotic blebbings. This paper analyzes various segmentation methods for bleb extraction in hESC videos and introduces a bio-inspired score function to improve the performance in bleb extraction. Full bleb formation consists of bleb expansion and retraction. Blebs change their size and image properties dynamically in both processes and between frames. Therefore, adaptive parameters are needed for each segmentation method. A score function derived from the change of bleb area and orientation between consecutive frames is proposed which provides adaptive parameters for bleb extraction in videos. In comparison to manual analysis, the proposed method provides an automated fast and accurate approach for bleb sequence extraction.
Still-to-video face recognition in unconstrained environments
NASA Astrophysics Data System (ADS)
Wang, Haoyu; Liu, Changsong; Ding, Xiaoqing
2015-02-01
Face images from video sequences captured in unconstrained environments usually contain several kinds of variations, e.g. pose, facial expression, illumination, image resolution and occlusion. Motion blur and compression artifacts also deteriorate recognition performance. Besides, in various practical systems such as law enforcement, video surveillance and e-passport identification, only a single still image per person is enrolled as the gallery set. Many existing methods may fail to work due to variations in face appearances and the limit of available gallery samples. In this paper, we propose a novel approach for still-to-video face recognition in unconstrained environments. By assuming that faces from still images and video frames share the same identity space, a regularized least squares regression method is utilized to tackle the multi-modality problem. Regularization terms based on heuristic assumptions are enrolled to avoid overfitting. In order to deal with the single image per person problem, we exploit face variations learned from training sets to synthesize virtual samples for gallery samples. We adopt a learning algorithm combining both affine/convex hull-based approach and regularizations to match image sets. Experimental results on a real-world dataset consisting of unconstrained video sequences demonstrate that our method outperforms the state-of-the-art methods impressively.
A novel visual saliency detection method for infrared video sequences
NASA Astrophysics Data System (ADS)
Wang, Xin; Zhang, Yuzhen; Ning, Chen
2017-12-01
Infrared video applications such as target detection and recognition, moving target tracking, and so forth can benefit a lot from visual saliency detection, which is essentially a method to automatically localize the ;important; content in videos. In this paper, a novel visual saliency detection method for infrared video sequences is proposed. Specifically, for infrared video saliency detection, both the spatial saliency and temporal saliency are considered. For spatial saliency, we adopt a mutual consistency-guided spatial cues combination-based method to capture the regions with obvious luminance contrast and contour features. For temporal saliency, a multi-frame symmetric difference approach is proposed to discriminate salient moving regions of interest from background motions. Then, the spatial saliency and temporal saliency are combined to compute the spatiotemporal saliency using an adaptive fusion strategy. Besides, to highlight the spatiotemporal salient regions uniformly, a multi-scale fusion approach is embedded into the spatiotemporal saliency model. Finally, a Gestalt theory-inspired optimization algorithm is designed to further improve the reliability of the final saliency map. Experimental results demonstrate that our method outperforms many state-of-the-art saliency detection approaches for infrared videos under various backgrounds.
Automatic summarization of soccer highlights using audio-visual descriptors.
Raventós, A; Quijada, R; Torres, Luis; Tarrés, Francesc
2015-01-01
Automatic summarization generation of sports video content has been object of great interest for many years. Although semantic descriptions techniques have been proposed, many of the approaches still rely on low-level video descriptors that render quite limited results due to the complexity of the problem and to the low capability of the descriptors to represent semantic content. In this paper, a new approach for automatic highlights summarization generation of soccer videos using audio-visual descriptors is presented. The approach is based on the segmentation of the video sequence into shots that will be further analyzed to determine its relevance and interest. Of special interest in the approach is the use of the audio information that provides additional robustness to the overall performance of the summarization system. For every video shot a set of low and mid level audio-visual descriptors are computed and lately adequately combined in order to obtain different relevance measures based on empirical knowledge rules. The final summary is generated by selecting those shots with highest interest according to the specifications of the user and the results of relevance measures. A variety of results are presented with real soccer video sequences that prove the validity of the approach.
Kätsyri, Jari; Hari, Riitta; Ravaja, Niklas; Nummenmaa, Lauri
2013-01-01
Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players' active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins) and failures (losses) in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing) and watched a pre-recorded gameplay video (vicarious playing) while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI). Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC) during winning than losing, both during active and vicarious playing. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing. PMID:23781195
Kätsyri, Jari; Hari, Riitta; Ravaja, Niklas; Nummenmaa, Lauri
2013-01-01
Although the multimodal stimulation provided by modern audiovisual video games is pleasing by itself, the rewarding nature of video game playing depends critically also on the players' active engagement in the gameplay. The extent to which active engagement influences dopaminergic brain reward circuit responses remains unsettled. Here we show that striatal reward circuit responses elicited by successes (wins) and failures (losses) in a video game are stronger during active than vicarious gameplay. Eleven healthy males both played a competitive first-person tank shooter game (active playing) and watched a pre-recorded gameplay video (vicarious playing) while their hemodynamic brain activation was measured with 3-tesla functional magnetic resonance imaging (fMRI). Wins and losses were paired with symmetrical monetary rewards and punishments during active and vicarious playing so that the external reward context remained identical during both conditions. Brain activation was stronger in the orbitomedial prefrontal cortex (omPFC) during winning than losing, both during active and vicarious playing. In contrast, both wins and losses suppressed activations in the midbrain and striatum during active playing; however, the striatal suppression, particularly in the anterior putamen, was more pronounced during loss than win events. Sensorimotor confounds related to joystick movements did not account for the results. Self-ratings indicated losing to be more unpleasant during active than vicarious playing. Our findings demonstrate striatum to be selectively sensitive to self-acquired rewards, in contrast to frontal components of the reward circuit that process both self-acquired and passively received rewards. We propose that the striatal responses to repeated acquisition of rewards that are contingent on game related successes contribute to the motivational pull of video-game playing.
On continuous user authentication via typing behavior.
Roth, Joseph; Liu, Xiaoming; Metaxas, Dimitris
2014-10-01
We hypothesize that an individual computer user has a unique and consistent habitual pattern of hand movements, independent of the text, while typing on a keyboard. As a result, this paper proposes a novel biometric modality named typing behavior (TB) for continuous user authentication. Given a webcam pointing toward a keyboard, we develop real-time computer vision algorithms to automatically extract hand movement patterns from the video stream. Unlike the typical continuous biometrics, such as keystroke dynamics (KD), TB provides a reliable authentication with a short delay, while avoiding explicit key-logging. We collect a video database where 63 unique subjects type static text and free text for multiple sessions. For one typing video, the hands are segmented in each frame and a unique descriptor is extracted based on the shape and position of hands, as well as their temporal dynamics in the video sequence. We propose a novel approach, named bag of multi-dimensional phrases, to match the cross-feature and cross-temporal pattern between a gallery sequence and probe sequence. The experimental results demonstrate a superior performance of TB when compared with KD, which, together with our ultrareal-time demo system, warrant further investigation of this novel vision application and biometric modality.
Leszczuk, Mikołaj; Dudek, Łukasz; Witkowski, Marcin
The VQiPS (Video Quality in Public Safety) Working Group, supported by the U.S. Department of Homeland Security, has been developing a user guide for public safety video applications. According to VQiPS, five parameters have particular importance influencing the ability to achieve a recognition task. They are: usage time-frame, discrimination level, target size, lighting level, and level of motion. These parameters form what are referred to as Generalized Use Classes (GUCs). The aim of our research was to develop algorithms that would automatically assist classification of input sequences into one of the GUCs. Target size and lighting level parameters were approached. The experiment described reveals the experts' ambiguity and hesitation during the manual target size determination process. However, the automatic methods developed for target size classification make it possible to determine GUC parameters with 70 % compliance to the end-users' opinion. Lighting levels of the entire sequence can be classified with an efficiency reaching 93 %. To make the algorithms available for use, a test application has been developed. It is able to process video files and display classification results, the user interface being very simple and requiring only minimal user interaction.
A Content Analysis of YouTubeTM Videos Related to Prostate Cancer.
Basch, Corey H; Menafro, Anthony; Mongiovi, Jennifer; Hillyer, Grace Clarke; Basch, Charles E
2016-09-29
In the United States, prostate cancer is the most common type of cancer in men after skin cancer. There is a paucity of research devoted to the types of prostate cancer information available on social media outlets. YouTube TM is a widely used video sharing website, which is emerging as commonplace for information related to health. The purpose of this study was to describe the most widely viewed YouTube TM videos related to prostate cancer. The 100 videos were watched a total of 50,278,770 times. The majority of videos were uploaded by consumers (45.0%) and medical or government professionals (30%). The purpose of most videos (78.0%) was to provide information, followed by discussions of prostate cancer treatment (51%) and prostate-specific antigen testing and routine screening (26%). All videos uploaded by medical and government professionals and 93.8% of videos uploaded by news sources provided information compared with about two thirds of consumer and less than one half of commercial and advertisement videos (p < .001). As society becomes increasingly technology-based, there is a need to help consumers acquire knowledge and skills to identify credible information to help inform their decisions. © The Author(s) 2016.
Artificial Neural Network applied to lightning flashes
NASA Astrophysics Data System (ADS)
Gin, R. B.; Guedes, D.; Bianchi, R.
2013-05-01
The development of video cameras enabled cientists to study lightning discharges comportment with more precision. The main goal of this project is to create a system able to detect images of lightning discharges stored in videos and classify them using an Artificial Neural Network (ANN)using C Language and OpenCV libraries. The developed system, can be split in two different modules: detection module and classification module. The detection module uses OpenCV`s computer vision libraries and image processing techniques to detect if there are significant differences between frames in a sequence, indicating that something, still not classified, occurred. Whenever there is a significant difference between two consecutive frames, two main algorithms are used to analyze the frame image: brightness and shape algorithms. These algorithms detect both shape and brightness of the event, removing irrelevant events like birds, as well as detecting the relevant events exact position, allowing the system to track it over time. The classification module uses a neural network to classify the relevant events as horizontal or vertical lightning, save the event`s images and calculates his number of discharges. The Neural Network was implemented using the backpropagation algorithm, and was trained with 42 training images , containing 57 lightning events (one image can have more than one lightning). TheANN was tested with one to five hidden layers, with up to 50 neurons each. The best configuration achieved a success rate of 95%, with one layer containing 20 neurons (33 test images with 42 events were used in this phase). This configuration was implemented in the developed system to analyze 20 video files, containing 63 lightning discharges previously manually detected. Results showed that all the lightning discharges were detected, many irrelevant events were unconsidered, and the event's number of discharges was correctly computed. The neural network used in this project achieved a success rate of 90%. The videos used in this experiment were acquired by seven video cameras installed in São Bernardo do Campo, Brazil, that continuously recorded lightning events during the summer. The cameras were disposed in a 360 loop, recording all data at a time resolution of 33ms. During this period, several convective storms were recorded.
NASA Astrophysics Data System (ADS)
Witt, Tanja; Walter, Thomas R.
2017-01-01
Lava fountains are a common eruptive feature of basaltic volcanoes. Many lava fountains result from fissure eruptions and are associated with the alignment of active vents and rising gas bubbles in the conduit. Visual reports suggest that lava fountain pulses may occur in chorus at adjacent vents. The mechanisms behind such a chorus of lava fountains and the underlying processes are, however, not fully understood. The March 2011 eruption at Pu'u 'Ō'ō (Kilauea volcano) was an exceptional fissure eruption that was well monitored and could be closely approached by field geologists. The fissure eruption occurred along groups of individual vents aligned above the feeding dyke. We investigate video data acquired during the early stages of the eruption to measure the height, width and velocity of the ejecta leaving eight vents. Using a Sobel edge-detection algorithm, the activity level of the lava fountains at the vents was determined, revealing a similarity in the eruption height and frequency. Based on this lava fountain time series, we estimate the direction and degree of correlation between the different vents. We find that the height and velocity of the eruptions display a small but systematic shift in time along the vents, indicating a lateral migration of lava fountaining at a rate of 11 m/s from W to E. This finding is in agreement with a propagation model of a pressure wave originating at the Kilauea volcano and propagating through the dyke at 10 m/s from W to E. Based on this approach from videos only 30 s long, we are able to obtain indirect constraints on the physical dyke parameters, with important implications for lateral magma flow processes at depth. This work shows that the recording and analysis of video data provide important constraints on the mechanisms of lava fountain pulses. Even though the video sequence is short, it allows for the confirmation of the magma propagation direction and a first-order estimation of the dyke dimensions.
A robust coding scheme for packet video
NASA Technical Reports Server (NTRS)
Chen, Y. C.; Sayood, Khalid; Nelson, D. J.
1991-01-01
We present a layered packet video coding algorithm based on a progressive transmission scheme. The algorithm provides good compression and can handle significant packet loss with graceful degradation in the reconstruction sequence. Simulation results for various conditions are presented.
A robust coding scheme for packet video
NASA Technical Reports Server (NTRS)
Chen, Yun-Chung; Sayood, Khalid; Nelson, Don J.
1992-01-01
A layered packet video coding algorithm based on a progressive transmission scheme is presented. The algorithm provides good compression and can handle significant packet loss with graceful degradation in the reconstruction sequence. Simulation results for various conditions are presented.
Image and Video Compression with VLSI Neural Networks
NASA Technical Reports Server (NTRS)
Fang, W.; Sheu, B.
1993-01-01
An advanced motion-compensated predictive video compression system based on artificial neural networks has been developed to effectively eliminate the temporal and spatial redundancy of video image sequences and thus reduce the bandwidth and storage required for the transmission and recording of the video signal. The VLSI neuroprocessor for high-speed high-ratio image compression based upon a self-organization network and the conventional algorithm for vector quantization are compared. The proposed method is quite efficient and can achieve near-optimal results.
Lossless Video Sequence Compression Using Adaptive Prediction
NASA Technical Reports Server (NTRS)
Li, Ying; Sayood, Khalid
2007-01-01
We present an adaptive lossless video compression algorithm based on predictive coding. The proposed algorithm exploits temporal, spatial, and spectral redundancies in a backward adaptive fashion with extremely low side information. The computational complexity is further reduced by using a caching strategy. We also study the relationship between the operational domain for the coder (wavelet or spatial) and the amount of temporal and spatial redundancy in the sequence being encoded. Experimental results show that the proposed scheme provides significant improvements in compression efficiencies.
Science documentary video slides to enhance education and communication
NASA Astrophysics Data System (ADS)
Byrne, J. M.; Little, L. J.; Dodgson, K.
2010-12-01
Documentary production can convey powerful messages using a combination of authentic science and reinforcing video imagery. Conventional documentary production contains too much information for many viewers to follow; hence many powerful points may be lost. But documentary productions that are re-edited into short video sequences and made available through web based video servers allow the teacher/viewer to access the material as video slides. Each video slide contains one critical discussion segment of the larger documentary. A teacher/viewer can review the documentary one segment at a time in a class room, public forum, or in the comfort of home. The sequential presentation of the video slides allows the viewer to best absorb the documentary message. The website environment provides space for additional questions and discussion to enhance the video message.
Activity recognition using Video Event Segmentation with Text (VEST)
NASA Astrophysics Data System (ADS)
Holloway, Hillary; Jones, Eric K.; Kaluzniacki, Andrew; Blasch, Erik; Tierno, Jorge
2014-06-01
Multi-Intelligence (multi-INT) data includes video, text, and signals that require analysis by operators. Analysis methods include information fusion approaches such as filtering, correlation, and association. In this paper, we discuss the Video Event Segmentation with Text (VEST) method, which provides event boundaries of an activity to compile related message and video clips for future interest. VEST infers meaningful activities by clustering multiple streams of time-sequenced multi-INT intelligence data and derived fusion products. We discuss exemplar results that segment raw full-motion video (FMV) data by using extracted commentary message timestamps, FMV metadata, and user-defined queries.
NASA's Myriad Uses of Digital Video
NASA Technical Reports Server (NTRS)
Grubbs, Rodney; Lindblom, Walt; George, Sandy
1999-01-01
Since it's inception, NASA has created many of the most memorable images seen this Century. From the fuzzy video of Neil Armstrong taking that first step on the moon, to images of the Mars surface available to all on the internet, NASA has provided images to inspire a generation, all because a scientist or researcher had a requirement to see something unusual. Digital Television technology will give NASA unprecedented new tools for acquiring, analyzing, and distributing video. This paper will explore NASA's DTV future. The agency has a requirement to move video from one NASA Center to another, in real time. Specifics will be provided relating to the NASA video infrastructure, including video from the Space Shuttle and from the various Centers. A comparison of the pros and cons of interlace and progressive scanned images will be presented. Film is a major component of NASA's image acquisition for analysis usage. The future of film within the context of DTV will be explored.
Marcos, Ma Shiela Angeli; David, Laura; Peñaflor, Eileen; Ticzon, Victor; Soriano, Maricor
2008-10-01
We introduce an automated benthic counting system in application for rapid reef assessment that utilizes computer vision on subsurface underwater reef video. Video acquisition was executed by lowering a submersible bullet-type camera from a motor boat while moving across the reef area. A GPS and echo sounder were linked to the video recorder to record bathymetry and location points. Analysis of living and non-living components was implemented through image color and texture feature extraction from the reef video frames and classification via Linear Discriminant Analysis. Compared to common rapid reef assessment protocols, our system can perform fine scale data acquisition and processing in one day. Reef video was acquired in Ngedarrak Reef, Koror, Republic of Palau. Overall success performance ranges from 60% to 77% for depths of 1 to 3 m. The development of an automated rapid reef classification system is most promising for reef studies that need fast and frequent data acquisition of percent cover of living and nonliving components.
NASA Astrophysics Data System (ADS)
Fritz, H. M.; Phillips, D. A.; Okayasu, A.; Shimozono, T.; Liu, H.; Takeda, S.; Mohammed, F.; Skanavis, V.; Synolakis, C. E.; Takahashi, T.
2012-12-01
The March 11, 2011, magnitude Mw 9.0 earthquake off the coast of the Tohoku region caused catastrophic damage and loss of life in Japan. The mid-afternoon tsunami arrival combined with survivors equipped with cameras on top of vertical evacuation buildings provided spontaneous spatially and temporally resolved inundation recordings. This report focuses on the surveys at 9 tsunami eyewitness video recording locations in Myako, Kamaishi, Kesennuma and Yoriisohama along Japan's Sanriku coast and the subsequent video image calibration, processing, tsunami hydrograph and flow velocity analysis. Selected tsunami video recording sites were explored, eyewitnesses interviewed and some ground control points recorded during the initial tsunami reconnaissance in April, 2011. A follow-up survey in June, 2011 focused on terrestrial laser scanning (TLS) at locations with high quality eyewitness videos. We acquired precise topographic data using TLS at the video sites producing a 3-dimensional "point cloud" dataset. A camera mounted on the Riegl VZ-400 scanner yields photorealistic 3D images. Integrated GPS measurements allow accurate georeferencing. The original video recordings were recovered from eyewitnesses and the Japanese Coast Guard (JCG). The analysis of the tsunami videos follows an adapted four step procedure originally developed for the analysis of 2004 Indian Ocean tsunami videos at Banda Aceh, Indonesia (Fritz et al., 2006). The first step requires the calibration of the sector of view present in the eyewitness video recording based on ground control points measured in the LiDAR data. In a second step the video image motion induced by the panning of the video camera was determined from subsequent images by particle image velocimetry (PIV) applied to fixed objects. The third step involves the transformation of the raw tsunami video images from image coordinates to world coordinates with a direct linear transformation (DLT) procedure. Finally, the instantaneous tsunami surface current and flooding velocity vector maps are determined by applying the digital PIV analysis method to the rectified tsunami video images with floating debris clusters. Tsunami currents up to 11 m/s per second were measured in Kesennuma Bay making navigation impossible. Tsunami hydrographs are derived from the videos based on water surface elevations at surface piercing objects identified in the acquired topographic TLS data. Apart from a dominant tsunami crest the hydrograph at Kamaishi also reveals a subsequent draw down to -10m exposing the harbor bottom. In some cases ship moorings resist the main tsunami crest only to be broken by the extreme draw down and setting vessels a drift for hours. Further we discuss the complex effects of coastal structures on inundation and outflow hydrographs and flow velocities.;
Automatic video segmentation and indexing
NASA Astrophysics Data System (ADS)
Chahir, Youssef; Chen, Liming
1999-08-01
Indexing is an important aspect of video database management. Video indexing involves the analysis of video sequences, which is a computationally intensive process. However, effective management of digital video requires robust indexing techniques. The main purpose of our proposed video segmentation is twofold. Firstly, we develop an algorithm that identifies camera shot boundary. The approach is based on the use of combination of color histograms and block-based technique. Next, each temporal segment is represented by a color reference frame which specifies the shot similarities and which is used in the constitution of scenes. Experimental results using a variety of videos selected in the corpus of the French Audiovisual National Institute are presented to demonstrate the effectiveness of performing shot detection, the content characterization of shots and the scene constitution.
Video bioinformatics analysis of human embryonic stem cell colony growth.
Lin, Sabrina; Fonteno, Shawn; Satish, Shruthi; Bhanu, Bir; Talbot, Prue
2010-05-20
Because video data are complex and are comprised of many images, mining information from video material is difficult to do without the aid of computer software. Video bioinformatics is a powerful quantitative approach for extracting spatio-temporal data from video images using computer software to perform dating mining and analysis. In this article, we introduce a video bioinformatics method for quantifying the growth of human embryonic stem cells (hESC) by analyzing time-lapse videos collected in a Nikon BioStation CT incubator equipped with a camera for video imaging. In our experiments, hESC colonies that were attached to Matrigel were filmed for 48 hours in the BioStation CT. To determine the rate of growth of these colonies, recipes were developed using CL-Quant software which enables users to extract various types of data from video images. To accurately evaluate colony growth, three recipes were created. The first segmented the image into the colony and background, the second enhanced the image to define colonies throughout the video sequence accurately, and the third measured the number of pixels in the colony over time. The three recipes were run in sequence on video data collected in a BioStation CT to analyze the rate of growth of individual hESC colonies over 48 hours. To verify the truthfulness of the CL-Quant recipes, the same data were analyzed manually using Adobe Photoshop software. When the data obtained using the CL-Quant recipes and Photoshop were compared, results were virtually identical, indicating the CL-Quant recipes were truthful. The method described here could be applied to any video data to measure growth rates of hESC or other cells that grow in colonies. In addition, other video bioinformatics recipes can be developed in the future for other cell processes such as migration, apoptosis, and cell adhesion.
Microbial evolution of sulphate reduction when lateral gene transfer is geographically restricted.
Chi Fru, E
2011-07-01
Lateral gene transfer (LGT) is an important mechanism by which micro-organisms acquire new functions. This process has been suggested to be central to prokaryotic evolution in various environments. However, the influence of geographical constraints on the evolution of laterally acquired genes in microbial metabolic evolution is not yet well understood. In this study, the influence of geographical isolation on the evolution of laterally acquired dissimilatory sulphite reductase (dsr) gene sequences in the sulphate-reducing micro-organisms (SRM) was investigated. Sequences on four continental blocks related to SRM known to have received dsr by LGT were analysed using standard phylogenetic and multidimensional statistical methods. Sequences related to lineages with large genetic diversity correlated positively with habitat divergence. Those affiliated to Thermodesulfobacterium indicated strong biogeographical delineation; hydrothermal-vent sequences clustered independently from hot-spring sequences. Some of the hydrothermal-vent and hot-spring sequences suggested to have been acquired from a common ancestral source may have diverged upon isolation within distinct habitats. In contrast, analysis of some Desulfotomaculum sequences indicated they could have been transferred from different ancestral sources but converged upon isolation within the same niche. These results hint that, after lateral acquisition of dsr genes, barriers to gene flow probably play a strong role in their subsequent evolution.
Influence of violent video gaming on determinants of the acquired capability for suicide.
Teismann, Tobias; Förtsch, Eva-Maria A D; Baumgart, Patrick; Het, Serkan; Michalak, Johannes
2014-01-30
The interpersonal theory of suicidal behavior proposes that fearlessness of death and physical pain insensitivity is a necessary requisite for self-inflicted lethal self-harm. Repeated experiences with painful and provocative events are supposed to cause an incremental increase in acquired capability. The present study examined whether playing a first-person shooter-game in contrast to a first-person racing game increases pain tolerance, a dimension of the acquired capability construct, and risk-taking behavior, a risk factor for developing acquired capability. N=81 male participants were randomly assigned to either play an action-shooter or a racing game before engaging in a game on risk-taking behavior and performing a cold pressor task (CPT). Participants exhibited higher pain tolerance after playing an action shooter game than after playing a racing game. Furthermore, playing an action shooter was generally associated with heightened risk-taking behavior. Group-differences were not attributable to the effects of the different types of games on self-reported mood and arousal. Overall these results indicate that action-shooter gaming alters pain tolerance and risk-taking behavior. Therefore, it may well be that long-term consumption of violent video games increases a person's capability to enact lethal self-harm. © 2013 Published by Elsevier Ireland Ltd.
Landsat 3 return beam vidicon response artifacts
,; Clark, B.
1981-01-01
The return beam vidicon (RBV) sensing systems employed aboard Landsats 1, 2, and 3 have all been similar in that they have utilized vidicon tube cameras. These are not mirror-sweep scanning devices such as the multispectral scanner (MSS) sensors that have also been carried aboard the Landsat satellites. The vidicons operate more like common television cameras, using an electron gun to read images from a photoconductive faceplate.In the case of Landsats 1 and 2, the RBV system consisted of three such vidicons which collected remote sensing data in three distinct spectral bands. Landsat 3, however, utilizes just two vidicon cameras, both of which sense data in a single broad band. The Landsat 3 RBV system additionally has a unique configuration. As arranged, the two cameras can be shuttered alternately, twice each, in the same time it takes for one MSS scene to be acquired. This shuttering sequence results in four RBV "subscenes" for every MSS scene acquired, similar to the four quadrants of a square. See Figure 1. Each subscene represents a ground area of approximately 98 by 98 km. The subscenes are designated A, B, C, and D, for the northwest, northeast, southwest, and southeast quarters of the full scene, respectively. RBV data products are normally ordered, reproduced, and sold on a subscene basis and are in general referred to in this way. Each exposure from the RBV camera system presents an image which is 98 km on a side. When these analog video data are subsequently converted to digital form, the picture element, or pixel, that results is 19 m on a side with an effective resolution element of 30 m. This pixel size is substantially smaller than that obtainable in MSS images (the MSS has an effective resolution element of 73.4 m), and, when RBV images are compared to equivalent MSS images, better resolution in the RBV data is clearly evident. It is for this reason that the RBV system can be a valuable tool for remote sensing of earth resources.Until recently, RBV imagery was processed directly from wideband video tape data onto 70-mm film. This changed in September 1980 when digital production of RBV data at the NASA Goddard Space Flight Center (GSFC) began. The wideband video tape data are now subjected to analog-to-digital preprocessing and corrected both radiometrically and geometrically to produce high-density digital tapes (HDT's). The HDT data are subsequently transmitted via satellite (Domsat) to the EROS Data Center (EDC) where they are used to generate 241-mm photographic images at a scale of 1:500,000. Computer-compatible tapes of the data are also generated as digital products. Of the RBV data acquired since September 1, 1980, approximately 2,800 subscenes per month have been processed at EDC.
NASA Astrophysics Data System (ADS)
Froehlich, Jan; Grandinetti, Stefan; Eberhardt, Bernd; Walter, Simon; Schilling, Andreas; Brendel, Harald
2014-03-01
High quality video sequences are required for the evaluation of tone mapping operators and high dynamic range (HDR) displays. We provide scenic and documentary scenes with a dynamic range of up to 18 stops. The scenes are staged using professional film lighting, make-up and set design to enable the evaluation of image and material appearance. To address challenges for HDR-displays and temporal tone mapping operators, the sequences include highlights entering and leaving the image, brightness changing over time, high contrast skin tones, specular highlights and bright, saturated colors. HDR-capture is carried out using two cameras mounted on a mirror-rig. To achieve a cinematic depth of field, digital motion picture cameras with Super-35mm size sensors are used. We provide HDR-video sequences to serve as a common ground for the evaluation of temporal tone mapping operators and HDR-displays. They are available to the scientific community for further research.
Automated frame selection process for high-resolution microendoscopy
NASA Astrophysics Data System (ADS)
Ishijima, Ayumu; Schwarz, Richard A.; Shin, Dongsuk; Mondrik, Sharon; Vigneswaran, Nadarajah; Gillenwater, Ann M.; Anandasabapathy, Sharmila; Richards-Kortum, Rebecca
2015-04-01
We developed an automated frame selection algorithm for high-resolution microendoscopy video sequences. The algorithm rapidly selects a representative frame with minimal motion artifact from a short video sequence, enabling fully automated image analysis at the point-of-care. The algorithm was evaluated by quantitative comparison of diagnostically relevant image features and diagnostic classification results obtained using automated frame selection versus manual frame selection. A data set consisting of video sequences collected in vivo from 100 oral sites and 167 esophageal sites was used in the analysis. The area under the receiver operating characteristic curve was 0.78 (automated selection) versus 0.82 (manual selection) for oral sites, and 0.93 (automated selection) versus 0.92 (manual selection) for esophageal sites. The implementation of fully automated high-resolution microendoscopy at the point-of-care has the potential to reduce the number of biopsies needed for accurate diagnosis of precancer and cancer in low-resource settings where there may be limited infrastructure and personnel for standard histologic analysis.
van der Kuil, Milan N. A.; Visser-Meily, Johanna M. A.; Evers, Andrea W. M.; van der Ham, Ineke J. M.
2018-01-01
Acquired brain injury patients often report navigation impairments. A cognitive rehabilitation therapy has been designed in the form of a serious game. The aim of the serious game is to aid patients in the development of compensatory navigation strategies by providing exercises in 3D virtual environments on their home computers. The objective of this study was to assess the usability of three critical gaming attributes: movement control in 3D virtual environments, instruction modality and feedback timing. Thirty acquired brain injury patients performed three tasks in which objective measures of usability were obtained. Mouse controlled movement was compared to keyboard controlled movement in a navigation task. Text-based instructions were compared to video-based instructions in a knowledge acquisition task. The effect of feedback timing on performance and motivation was examined in a navigation training game. Subjective usability ratings of all design options were assessed using questionnaires. Results showed that mouse controlled interaction in 3D environments is more effective than keyboard controlled interaction. Patients clearly preferred video-based instructions over text-based instructions, even though video-based instructions were not more effective in context of knowledge acquisition and comprehension. No effect of feedback timing was found on performance and motivation in games designed to train navigation abilities. Overall appreciation of the serious game was positive. The results provide valuable insights in the design choices that facilitate the transfer of skills from serious games to real-life situations. PMID:29922196
van der Kuil, Milan N A; Visser-Meily, Johanna M A; Evers, Andrea W M; van der Ham, Ineke J M
2018-01-01
Acquired brain injury patients often report navigation impairments. A cognitive rehabilitation therapy has been designed in the form of a serious game. The aim of the serious game is to aid patients in the development of compensatory navigation strategies by providing exercises in 3D virtual environments on their home computers. The objective of this study was to assess the usability of three critical gaming attributes: movement control in 3D virtual environments, instruction modality and feedback timing. Thirty acquired brain injury patients performed three tasks in which objective measures of usability were obtained. Mouse controlled movement was compared to keyboard controlled movement in a navigation task. Text-based instructions were compared to video-based instructions in a knowledge acquisition task. The effect of feedback timing on performance and motivation was examined in a navigation training game. Subjective usability ratings of all design options were assessed using questionnaires. Results showed that mouse controlled interaction in 3D environments is more effective than keyboard controlled interaction. Patients clearly preferred video-based instructions over text-based instructions, even though video-based instructions were not more effective in context of knowledge acquisition and comprehension. No effect of feedback timing was found on performance and motivation in games designed to train navigation abilities. Overall appreciation of the serious game was positive. The results provide valuable insights in the design choices that facilitate the transfer of skills from serious games to real-life situations.
Subjective evaluation of H.265/HEVC based dynamic adaptive video streaming over HTTP (HEVC-DASH)
NASA Astrophysics Data System (ADS)
Irondi, Iheanyi; Wang, Qi; Grecos, Christos
2015-02-01
The Dynamic Adaptive Streaming over HTTP (DASH) standard is becoming increasingly popular for real-time adaptive HTTP streaming of internet video in response to unstable network conditions. Integration of DASH streaming techniques with the new H.265/HEVC video coding standard is a promising area of research. The performance of HEVC-DASH systems has been previously evaluated by a few researchers using objective metrics, however subjective evaluation would provide a better measure of the user's Quality of Experience (QoE) and overall performance of the system. This paper presents a subjective evaluation of an HEVC-DASH system implemented in a hardware testbed. Previous studies in this area have focused on using the current H.264/AVC (Advanced Video Coding) or H.264/SVC (Scalable Video Coding) codecs and moreover, there has been no established standard test procedure for the subjective evaluation of DASH adaptive streaming. In this paper, we define a test plan for HEVC-DASH with a carefully justified data set employing longer video sequences that would be sufficient to demonstrate the bitrate switching operations in response to various network condition patterns. We evaluate the end user's real-time QoE online by investigating the perceived impact of delay, different packet loss rates, fluctuating bandwidth, and the perceived quality of using different DASH video stream segment sizes on a video streaming session using different video sequences. The Mean Opinion Score (MOS) results give an insight into the performance of the system and expectation of the users. The results from this study show the impact of different network impairments and different video segments on users' QoE and further analysis and study may help in optimizing system performance.
Keyhole imaging method for dynamic objects behind the occlusion area
NASA Astrophysics Data System (ADS)
Hao, Conghui; Chen, Xi; Dong, Liquan; Zhao, Yuejin; Liu, Ming; Kong, Lingqin; Hui, Mei; Liu, Xiaohua; Wu, Hong
2018-01-01
A method of keyhole imaging based on camera array is realized to obtain the video image behind a keyhole in shielded space at a relatively long distance. We get the multi-angle video images by using a 2×2 CCD camera array to take the images behind the keyhole in four directions. The multi-angle video images are saved in the form of frame sequences. This paper presents a method of video frame alignment. In order to remove the non-target area outside the aperture, we use the canny operator and morphological method to realize the edge detection of images and fill the images. The image stitching of four images is accomplished on the basis of the image stitching algorithm of two images. In the image stitching algorithm of two images, the SIFT method is adopted to accomplish the initial matching of images, and then the RANSAC algorithm is applied to eliminate the wrong matching points and to obtain a homography matrix. A method of optimizing transformation matrix is proposed in this paper. Finally, the video image with larger field of view behind the keyhole can be synthesized with image frame sequence in which every single frame is stitched. The results show that the screen of the video is clear and natural, the brightness transition is smooth. There is no obvious artificial stitching marks in the video, and it can be applied in different engineering environment .
Dynamic Textures Modeling via Joint Video Dictionary Learning.
Wei, Xian; Li, Yuanxiang; Shen, Hao; Chen, Fang; Kleinsteuber, Martin; Wang, Zhongfeng
2017-04-06
Video representation is an important and challenging task in the computer vision community. In this paper, we consider the problem of modeling and classifying video sequences of dynamic scenes which could be modeled in a dynamic textures (DT) framework. At first, we assume that image frames of a moving scene can be modeled as a Markov random process. We propose a sparse coding framework, named joint video dictionary learning (JVDL), to model a video adaptively. By treating the sparse coefficients of image frames over a learned dictionary as the underlying "states", we learn an efficient and robust linear transition matrix between two adjacent frames of sparse events in time series. Hence, a dynamic scene sequence is represented by an appropriate transition matrix associated with a dictionary. In order to ensure the stability of JVDL, we impose several constraints on such transition matrix and dictionary. The developed framework is able to capture the dynamics of a moving scene by exploring both sparse properties and the temporal correlations of consecutive video frames. Moreover, such learned JVDL parameters can be used for various DT applications, such as DT synthesis and recognition. Experimental results demonstrate the strong competitiveness of the proposed JVDL approach in comparison with state-of-the-art video representation methods. Especially, it performs significantly better in dealing with DT synthesis and recognition on heavily corrupted data.
Smartphone based automatic organ validation in ultrasound video.
Vaish, Pallavi; Bharath, R; Rajalakshmi, P
2017-07-01
Telesonography involves transmission of ultrasound video from remote areas to the doctors for getting diagnosis. Due to the lack of trained sonographers in remote areas, the ultrasound videos scanned by these untrained persons do not contain the proper information that is required by a physician. As compared to standard methods for video transmission, mHealth driven systems need to be developed for transmitting valid medical videos. To overcome this problem, we are proposing an organ validation algorithm to evaluate the ultrasound video based on the content present. This will guide the semi skilled person to acquire the representative data from patient. Advancement in smartphone technology allows us to perform high medical image processing on smartphone. In this paper we have developed an Application (APP) for a smartphone which can automatically detect the valid frames (which consist of clear organ visibility) in an ultrasound video and ignores the invalid frames (which consist of no-organ visibility), and produces a compressed sized video. This is done by extracting the GIST features from the Region of Interest (ROI) of the frame and then classifying the frame using SVM classifier with quadratic kernel. The developed application resulted with the accuracy of 94.93% in classifying valid and invalid images.
Semantic-based surveillance video retrieval.
Hu, Weiming; Xie, Dan; Fu, Zhouyu; Zeng, Wenrong; Maybank, Steve
2007-04-01
Visual surveillance produces large amounts of video data. Effective indexing and retrieval from surveillance video databases are very important. Although there are many ways to represent the content of video clips in current video retrieval algorithms, there still exists a semantic gap between users and retrieval systems. Visual surveillance systems supply a platform for investigating semantic-based video retrieval. In this paper, a semantic-based video retrieval framework for visual surveillance is proposed. A cluster-based tracking algorithm is developed to acquire motion trajectories. The trajectories are then clustered hierarchically using the spatial and temporal information, to learn activity models. A hierarchical structure of semantic indexing and retrieval of object activities, where each individual activity automatically inherits all the semantic descriptions of the activity model to which it belongs, is proposed for accessing video clips and individual objects at the semantic level. The proposed retrieval framework supports various queries including queries by keywords, multiple object queries, and queries by sketch. For multiple object queries, succession and simultaneity restrictions, together with depth and breadth first orders, are considered. For sketch-based queries, a method for matching trajectories drawn by users to spatial trajectories is proposed. The effectiveness and efficiency of our framework are tested in a crowded traffic scene.
Impact of an active video game on healthy children's physical activity.
Baranowski, Tom; Abdelsamad, Dina; Baranowski, Janice; O'Connor, Teresia Margareta; Thompson, Debbe; Barnett, Anthony; Cerin, Ester; Chen, Tzu-An
2012-03-01
This naturalistic study tests whether children receiving a new (to them) active video game spontaneously engage in more physical activity than those receiving an inactive video game, and whether the effect would be greater among children in unsafe neighborhoods, who might not be allowed to play outside. Participants were children 9 to 12 years of age, with a BMI >50th percentile, but <99th percentile; none of these children a medical condition that would preclude physical activity or playing video games. A randomized clinical trial assigned children to receiving 2 active or 2 inactive video games, the peripherals necessary to run the games, and a Wii console. Physical activity was monitored by using accelerometers for 5 weeks over the course of a 13-week experiment. Neighborhood safety was assessed with a 12 item validated questionnaire. There was no evidence that children receiving the active video games were more active in general, or at anytime, than children receiving the inactive video games. The outcomes were not moderated by parent perceived neighborhood safety, child BMI z score, or other demographic characteristics. These results provide no reason to believe that simply acquiring an active video game under naturalistic circumstances provides a public health benefit to children.
ERIC Educational Resources Information Center
Flowers, Susan K.; Easter, Carla; Holmes, Andrea; Cohen, Brian; Bednarski, April E.; Mardis, Elaine R.; Wilson, Richard K.; Elgin, Sarah C. R.
2005-01-01
Sequencing of the human genome has ushered in a new era of biology. The technologies developed to facilitate the sequencing of the human genome are now being applied to the sequencing of other genomes. In 2004, a partnership was formed between Washington University School of Medicine Genome Sequencing Center's Outreach Program and Washington…
Non-mydriatic video ophthalmoscope to measure fast temporal changes of the human retina
NASA Astrophysics Data System (ADS)
Tornow, Ralf P.; Kolář, Radim; Odstrčilík, Jan
2015-07-01
The analysis of fast temporal changes of the human retina can be used to get insight to normal physiological behavior and to detect pathological deviations. This can be important for the early detection of glaucoma and other eye diseases. We developed a small, lightweight, USB powered video ophthalmoscope that allows taking video sequences of the human retina with at least 25 frames per second without dilating the pupil. Short sequences (about 10 s) of the optic nerve head (20° x 15°) are recorded from subjects and registered offline using two-stage process (phase correlation and Lucas-Kanade approach) to compensate for eye movements. From registered video sequences, different parameters can be calculated. Two applications are described here: measurement of (i) cardiac cycle induced pulsatile reflection changes and (ii) eye movements and fixation pattern. Cardiac cycle induced pulsatile reflection changes are caused by changing blood volume in the retina. Waveform and pulse parameters like amplitude and rise time can be measured in any selected areas within the retinal image. Fixation pattern ΔY(ΔX) can be assessed from eye movements during video acquisition. The eye movements ΔX[t], ΔY[t] are derived from image registration results with high temporal (40 ms) and spatial (1,86 arcmin) resolution. Parameters of pulsatile reflection changes and fixation pattern can be affected in beginning glaucoma and the method described here may support early detection of glaucoma and other eye disease.
Object detection in cinematographic video sequences for automatic indexing
NASA Astrophysics Data System (ADS)
Stauder, Jurgen; Chupeau, Bertrand; Oisel, Lionel
2003-06-01
This paper presents an object detection framework applied to cinematographic post-processing of video sequences. Post-processing is done after production and before editing. At the beginning of each shot of a video, a slate (also called clapperboard) is shown. The slate contains notably an electronic audio timecode that is necessary for audio-visual synchronization. This paper presents an object detection framework to detect slates in video sequences for automatic indexing and post-processing. It is based on five steps. The first two steps aim to reduce drastically the video data to be analyzed. They ensure high recall rate but have low precision. The first step detects images at the beginning of a shot possibly showing up a slate while the second step searches in these images for candidates regions with color distribution similar to slates. The objective is to not miss any slate while eliminating long parts of video without slate appearance. The third and fourth steps are statistical classification and pattern matching to detected and precisely locate slates in candidate regions. These steps ensure high recall rate and high precision. The objective is to detect slates with very little false alarms to minimize interactive corrections. In a last step, electronic timecodes are read from slates to automize audio-visual synchronization. The presented slate detector has a recall rate of 89% and a precision of 97,5%. By temporal integration, much more than 89% of shots in dailies are detected. By timecode coherence analysis, the precision can be raised too. Issues for future work are to accelerate the system to be faster than real-time and to extend the framework for several slate types.
Video quality pooling adaptive to perceptual distortion severity.
Park, Jincheol; Seshadrinathan, Kalpana; Lee, Sanghoon; Bovik, Alan Conrad
2013-02-01
It is generally recognized that severe video distortions that are transient in space and/or time have a large effect on overall perceived video quality. In order to understand this phenomena, we study the distribution of spatio-temporally local quality scores obtained from several video quality assessment (VQA) algorithms on videos suffering from compression and lossy transmission over communication channels. We propose a content adaptive spatial and temporal pooling strategy based on the observed distribution. Our method adaptively emphasizes "worst" scores along both the spatial and temporal dimensions of a video sequence and also considers the perceptual effect of large-area cohesive motion flow such as egomotion. We demonstrate the efficacy of the method by testing it using three different VQA algorithms on the LIVE Video Quality database and the EPFL-PoliMI video quality database.
Method of determining the necessary number of observations for video stream documents recognition
NASA Astrophysics Data System (ADS)
Arlazarov, Vladimir V.; Bulatov, Konstantin; Manzhikov, Temudzhin; Slavin, Oleg; Janiszewski, Igor
2018-04-01
This paper discusses a task of document recognition on a sequence of video frames. In order to optimize the processing speed an estimation is performed of stability of recognition results obtained from several video frames. Considering identity document (Russian internal passport) recognition on a mobile device it is shown that significant decrease is possible of the number of observations necessary for obtaining precise recognition result.
Selective encryption for H.264/AVC video coding
NASA Astrophysics Data System (ADS)
Shi, Tuo; King, Brian; Salama, Paul
2006-02-01
Due to the ease with which digital data can be manipulated and due to the ongoing advancements that have brought us closer to pervasive computing, the secure delivery of video and images has become a challenging problem. Despite the advantages and opportunities that digital video provide, illegal copying and distribution as well as plagiarism of digital audio, images, and video is still ongoing. In this paper we describe two techniques for securing H.264 coded video streams. The first technique, SEH264Algorithm1, groups the data into the following blocks of data: (1) a block that contains the sequence parameter set and the picture parameter set, (2) a block containing a compressed intra coded frame, (3) a block containing the slice header of a P slice, all the headers of the macroblock within the same P slice, and all the luma and chroma DC coefficients belonging to the all the macroblocks within the same slice, (4) a block containing all the ac coefficients, and (5) a block containing all the motion vectors. The first three are encrypted whereas the last two are not. The second method, SEH264Algorithm2, relies on the use of multiple slices per coded frame. The algorithm searches the compressed video sequence for start codes (0x000001) and then encrypts the next N bits of data.
Visual content highlighting via automatic extraction of embedded captions on MPEG compressed video
NASA Astrophysics Data System (ADS)
Yeo, Boon-Lock; Liu, Bede
1996-03-01
Embedded captions in TV programs such as news broadcasts, documentaries and coverage of sports events provide important information on the underlying events. In digital video libraries, such captions represent a highly condensed form of key information on the contents of the video. In this paper we propose a scheme to automatically detect the presence of captions embedded in video frames. The proposed method operates on reduced image sequences which are efficiently reconstructed from compressed MPEG video and thus does not require full frame decompression. The detection, extraction and analysis of embedded captions help to capture the highlights of visual contents in video documents for better organization of video, to present succinctly the important messages embedded in the images, and to facilitate browsing, searching and retrieval of relevant clips.
Mahu, M; Pasmans, F; Vranckx, K; De Pauw, N; Vande Maele, L; Vyt, Philip; Vandersmissen, Tamara; Martel, A; Haesebrouck, F; Boyen, F
2017-08-01
Swine dysentery (SD) is an economically important disease for which antimicrobial treatment still occupies an important place to control outbreaks. However, acquired antimicrobial resistance is increasingly observed in Brachyspira hyodysenteriae. In this study, the Minimal Inhibitory Concentrations (MIC) of six antimicrobial compounds for 30 recent Belgian B. hyodysenteriae isolates were determined using a broth microdilution method. In addition, relevant regions of the 16S rRNA, 23S rRNA and the L3 protein encoding genes were sequenced to reveal mutations associated with acquired resistance. Finally, a phylogeny was reconstructed using minimal spanning tree analysis of multi locus sequence typing of the isolates. For lincomycin, doxycycline, tylosin and tylvalosin, at least 70% of the isolates did not belong to the wild-type population and were considered to have acquired resistance. For valnemulin and tiamulin, this was over 50%. In all isolates with acquired resistance to doxycycline, the G1058C mutation was present in their 16S rRNA gene. All isolates showing acquired resistance to lincomycin and both macrolides displayed the A2058T mutation in their 23S rRNA gene. Other mutations in this gene and the N148S mutation in the L3 protein were present in both wild-type isolates and isolates considered to have acquired resistance. Multi locus sequence analysis revealed a previously undescribed clonal complex, with 4 novel sequence types in which the majority of isolates showed acquired resistance to all tested antimicrobial products. In conclusion, acquired antimicrobial resistance is widespread among Belgian B. hyodysenteriae isolates. The emergence of multi-resistant clonal complexes can pose a threat to swine industry. Copyright © 2017 Elsevier B.V. All rights reserved.
Multilevel analysis of sports video sequences
NASA Astrophysics Data System (ADS)
Han, Jungong; Farin, Dirk; de With, Peter H. N.
2006-01-01
We propose a fully automatic and flexible framework for analysis and summarization of tennis broadcast video sequences, using visual features and specific game-context knowledge. Our framework can analyze a tennis video sequence at three levels, which provides a broad range of different analysis results. The proposed framework includes novel pixel-level and object-level tennis video processing algorithms, such as a moving-player detection taking both the color and the court (playing-field) information into account, and a player-position tracking algorithm based on a 3-D camera model. Additionally, we employ scene-level models for detecting events, like service, base-line rally and net-approach, based on a number real-world visual features. The system can summarize three forms of information: (1) all court-view playing frames in a game, (2) the moving trajectory and real-speed of each player, as well as relative position between the player and the court, (3) the semantic event segments in a game. The proposed framework is flexible in choosing the level of analysis that is desired. It is effective because the framework makes use of several visual cues obtained from the real-world domain to model important events like service, thereby increasing the accuracy of the scene-level analysis. The paper presents attractive experimental results highlighting the system efficiency and analysis capabilities.
Gear Shifting of Quadriceps during Isometric Knee Extension Disclosed Using Ultrasonography.
Zhang, Shu; Huang, Weijian; Zeng, Yu; Shi, Wenxiu; Diao, Xianfen; Wei, Xiguang; Ling, Shan
2018-01-01
Ultrasonography has been widely employed to estimate the morphological changes of muscle during contraction. To further investigate the motion pattern of quadriceps during isometric knee extensions, we studied the relative motion pattern between femur and quadriceps under ultrasonography. An interesting observation is that although the force of isometric knee extension can be controlled to change almost linearly, femur in the simultaneously captured ultrasound video sequences has several different piecewise moving patterns. This phenomenon is like quadriceps having several forward gear ratios like a car starting from rest towards maximal voluntary contraction (MVC) and then returning to rest. Therefore, to verify this assumption, we captured several ultrasound video sequences of isometric knee extension and collected the torque/force signal simultaneously. Then we extract the shapes of femur from these ultrasound video sequences using video processing techniques and study the motion pattern both qualitatively and quantitatively. The phenomenon can be seen easier via a comparison between the torque signal and relative spatial distance between femur and quadriceps. Furthermore, we use cluster analysis techniques to study the process and the clustering results also provided preliminary support to the conclusion that, during both ramp increasing and decreasing phases, quadriceps contraction may have several forward gear ratios relative to femur.
Parting Moon Shots from NASAs GRAIL Mission
2013-01-10
Video of the moon taken by the NASA GRAIL mission's MoonKam (Moon Knowledge Acquired by Middle School Students) camera aboard the Ebb spacecraft on Dec. 14, 2012. Features forward-facing and rear-facing views.
NASA Astrophysics Data System (ADS)
Chen, H.; Ye, Sh.; Nedzvedz, O. V.; Ablameyko, S. V.
2018-03-01
Study of crowd movement is an important practical problem, and its solution is used in video surveillance systems for preventing various emergency situations. In the general case, a group of fast-moving people is of more interest than a group of stationary or slow-moving people. We propose a new method for crowd movement analysis using a video sequence, based on integral optical flow. We have determined several characteristics of a moving crowd such as density, speed, direction of motion, symmetry, and in/out index. These characteristics are used for further analysis of a video scene.
Online tracking of outdoor lighting variations for augmented reality with moving cameras.
Liu, Yanli; Granier, Xavier
2012-04-01
In augmented reality, one of key tasks to achieve a convincing visual appearance consistency between virtual objects and video scenes is to have a coherent illumination along the whole sequence. As outdoor illumination is largely dependent on the weather, the lighting condition may change from frame to frame. In this paper, we propose a full image-based approach for online tracking of outdoor illumination variations from videos captured with moving cameras. Our key idea is to estimate the relative intensities of sunlight and skylight via a sparse set of planar feature-points extracted from each frame. To address the inevitable feature misalignments, a set of constraints are introduced to select the most reliable ones. Exploiting the spatial and temporal coherence of illumination, the relative intensities of sunlight and skylight are finally estimated by using an optimization process. We validate our technique on a set of real-life videos and show that the results with our estimations are visually coherent along the video sequences.
Navy Budget: Potential Reductions for Research, Development, Test, and Evaluation
1990-11-01
available for use in future Navy programs, including the MK-50 tor- pedo and Vertical Launch Antisubmarine Rocket. A total of $49.9 million of fiscal...346 Travel 03 07 + 04 Support 224 225 + 01 Total Requested $122.61 $122.61 -0- In addition, the Navy plans to acquire six Acoustic Video Processor...units at $2.4 million in fiscal year 1991. The Acoustic Video Processor pro- gram is experiencing development problems, and the full-scale develop- ment
Video-modelling to improve task completion in a child with autism.
Rayner, Christopher Stephen
2010-01-01
To evaluate the use of video modelling as an intervention for increasing task completion for individuals with autism who have high support needs. A 12-year-old-boy with autism received video modelling intervention on two routines (unpacking his bag and brushing his teeth). Use of the video modelling intervention led to rapid increases in the percentage of steps performed in the unpacking his bag sequence and these gains generalized to packing his bag prior to departure from school. There was limited success in the use of the video modelling intervention for teaching the participant to brush his teeth. Video modelling can be successfully applied to enhance daily functioning in a classroom environment for students with autism and high support needs.
Takeda, Naohito; Takeuchi, Isao; Haruna, Mitsumasa
2007-12-01
In order to develop an e-learning system that promotes self-learning, lectures and basic operations in laboratory practice of chemistry were recorded and edited on DVD media, consisting of 8 streaming videos as learning materials. Twenty-six students wanted to watch the DVD, and answered the following questions after they had watched it: "Do you think the video would serve to encourage you to study independently in the laboratory practice?" Almost all students (95%) approved of its usefulness, and more than 60% of them watched the videos repeatedly in order to acquire deeper knowledge and skill of the experimental operations. More than 60% answered that the demonstration-experiment should be continued in the laboratory practice, in spite of distribution of the DVD media.
Video model deformation system for the National Transonic Facility
NASA Technical Reports Server (NTRS)
Burner, A. W.; Snow, W. L.; Goad, W. K.
1983-01-01
A photogrammetric closed circuit television system to measure model deformation at the National Transonic Facility is described. The photogrammetric approach was chosen because of its inherent rapid data recording of the entire object field. Video cameras are used to acquire data instead of film cameras due to the inaccessibility of cameras which must be housed within the cryogenic, high pressure plenum of this facility. A rudimentary theory section is followed by a description of the video-based system and control measures required to protect cameras from the hostile environment. Preliminary results obtained with the same camera placement as planned for NTF are presented and plans for facility testing with a specially designed test wing are discussed.
Storage, retrieval, and edit of digital video using Motion JPEG
NASA Astrophysics Data System (ADS)
Sudharsanan, Subramania I.; Lee, D. H.
1994-04-01
In a companion paper we describe a Micro Channel adapter card that can perform real-time JPEG (Joint Photographic Experts Group) compression of a 640 by 480 24-bit image within 1/30th of a second. Since this corresponds to NTSC video rates at considerably good perceptual quality, this system can be used for real-time capture and manipulation of continuously fed video. To facilitate capturing the compressed video in a storage medium, an IBM Bus master SCSI adapter with cache is utilized. Efficacy of the data transfer mechanism is considerably improved using the System Control Block architecture, an extension to Micro Channel bus masters. We show experimental results that the overall system can perform at compressed data rates of about 1.5 MBytes/second sustained and with sporadic peaks to about 1.8 MBytes/second depending on the image sequence content. We also describe mechanisms to access the compressed data very efficiently through special file formats. This in turn permits creation of simpler sequence editors. Another advantage of the special file format is easy control of forward, backward and slow motion playback. The proposed method can be extended for design of a video compression subsystem for a variety of personal computing systems.
Final Report on Video Log Data Mining Project
DOT National Transportation Integrated Search
2012-06-01
This report describes the development of an automated computer vision system that identities and inventories road signs : from imagery acquired from the Kansas Department of Transportations road profiling system that takes images every 26.4 : feet...
Levac, Danielle; Miller, Patricia; Missiuna, Cheryl
2012-05-01
Little is known about how therapists promote learning of functional motor skills for children with acquired brain injuries. This study explores physiotherapists' description of these interventions in comparison to virtual reality (VR) video game-based therapy. Six physiotherapists employed at a children's rehabilitation center participated in semi-structured interviews, which were transcribed and analyzed using thematic analysis. Physiotherapists describe using interventions that motivate children to challenge performance quality and optimize real-life functioning. Intervention strategies are influenced by characteristics of the child, parent availability to practice skills outside therapy, and therapist experience. VR use motivates children to participate, but can influence therapist use of verbal strategies and complicate interventions. Physiotherapists consider unique characteristics of this population when providing interventions that promote learning of motor skills. The VR technology has advantageous features but its use with this population can be challenging; further research is recommended.
Increased fMRI Sensitivity at Equal Data Burden Using Averaged Shifted Echo Acquisition
Witt, Suzanne T.; Warntjes, Marcel; Engström, Maria
2016-01-01
There is growing evidence as to the benefits of collecting BOLD fMRI data with increased sampling rates. However, many of the newly developed acquisition techniques developed to collect BOLD data with ultra-short TRs require hardware, software, and non-standard analytic pipelines that may not be accessible to all researchers. We propose to incorporate the method of shifted echo into a standard multi-slice, gradient echo EPI sequence to achieve a higher sampling rate with a TR of <1 s with acceptable spatial resolution. We further propose to incorporate temporal averaging of consecutively acquired EPI volumes to both ameliorate the reduced temporal signal-to-noise inherent in ultra-fast EPI sequences and reduce the data burden. BOLD data were collected from 11 healthy subjects performing a simple, event-related visual-motor task with four different EPI sequences: (1) reference EPI sequence with TR = 1440 ms, (2) shifted echo EPI sequence with TR = 700 ms, (3) shifted echo EPI sequence with every two consecutively acquired EPI volumes averaged and effective TR = 1400 ms, and (4) shifted echo EPI sequence with every four consecutively acquired EPI volumes averaged and effective TR = 2800 ms. Both the temporally averaged sequences exhibited increased temporal signal-to-noise over the shifted echo EPI sequence. The shifted echo sequence with every two EPI volumes averaged also had significantly increased BOLD signal change compared with the other three sequences, while the shifted echo sequence with every four EPI volumes averaged had significantly decreased BOLD signal change compared with the other three sequences. The results indicated that incorporating the method of shifted echo into a standard multi-slice EPI sequence is a viable method for achieving increased sampling rate for collecting event-related BOLD data. Further, consecutively averaging every two consecutively acquired EPI volumes significantly increased the measured BOLD signal change and the subsequently calculated activation map statistics. PMID:27932947
NASA Astrophysics Data System (ADS)
Fritz, Hermann M.; Phillips, David A.; Okayasu, Akio; Shimozono, Takenori; Liu, Haijiang; Takeda, Seiichi; Mohammed, Fahad; Skanavis, Vassilis; Synolakis, Costas E.; Takahashi, Tomoyuki
2013-04-01
The March 11, 2011, magnitude Mw 9.0 earthquake off the Tohoku coast of Japan caused catastrophic damage and loss of life to a tsunami aware population. The mid-afternoon tsunami arrival combined with survivors equipped with cameras on top of vertical evacuation buildings provided fragmented spatially and temporally resolved inundation recordings. This report focuses on the surveys at 9 tsunami eyewitness video recording locations in Myako, Kamaishi, Kesennuma and Yoriisohama along Japan's Sanriku coast and the subsequent video image calibration, processing, tsunami hydrograph and flow velocity analysis. Selected tsunami video recording sites were explored, eyewitnesses interviewed and some ground control points recorded during the initial tsunami reconnaissance in April, 2011. A follow-up survey in June, 2011 focused on terrestrial laser scanning (TLS) at locations with high quality eyewitness videos. We acquired precise topographic data using TLS at the video sites producing a 3-dimensional "point cloud" dataset. A camera mounted on the Riegl VZ-400 scanner yields photorealistic 3D images. Integrated GPS measurements allow accurate georeferencing. The original video recordings were recovered from eyewitnesses and the Japanese Coast Guard (JCG). The analysis of the tsunami videos follows an adapted four step procedure originally developed for the analysis of 2004 Indian Ocean tsunami videos at Banda Aceh, Indonesia (Fritz et al., 2006). The first step requires the calibration of the sector of view present in the eyewitness video recording based on ground control points measured in the LiDAR data. In a second step the video image motion induced by the panning of the video camera was determined from subsequent images by particle image velocimetry (PIV) applied to fixed objects. The third step involves the transformation of the raw tsunami video images from image coordinates to world coordinates with a direct linear transformation (DLT) procedure. Finally, the instantaneous tsunami surface current and flooding velocity vector maps are determined by applying the digital PIV analysis method to the rectified tsunami video images with floating debris clusters. Tsunami currents up to 11 m/s were measured in Kesennuma Bay making navigation impossible (Fritz et al., 2012). Tsunami hydrographs are derived from the videos based on water surface elevations at surface piercing objects identified in the acquired topographic TLS data. Apart from a dominant tsunami crest the hydrograph at Kamaishi also reveals a subsequent draw down to minus 10m exposing the harbor bottom. In some cases ship moorings resist the main tsunami crest only to be broken by the extreme draw down and setting vessels a drift for hours. Further we discuss the complex effects of coastal structures on inundation and outflow hydrographs and flow velocities. Lastly a perspective on the recovery and reconstruction process is provided based on numerous revisits of identical sites between April 2011 and July 2012.
[Development of a video image system for wireless capsule endoscopes based on DSP].
Yang, Li; Peng, Chenglin; Wu, Huafeng; Zhao, Dechun; Zhang, Jinhua
2008-02-01
A video image recorder to record video picture for wireless capsule endoscopes was designed. TMS320C6211 DSP of Texas Instruments Inc. is the core processor of this system. Images are periodically acquired from Composite Video Broadcast Signal (CVBS) source and scaled by video decoder (SAA7114H). Video data is transported from high speed buffer First-in First-out (FIFO) to Digital Signal Processor (DSP) under the control of Complex Programmable Logic Device (CPLD). This paper adopts JPEG algorithm for image coding, and the compressed data in DSP was stored to Compact Flash (CF) card. TMS320C6211 DSP is mainly used for image compression and data transporting. Fast Discrete Cosine Transform (DCT) algorithm and fast coefficient quantization algorithm are used to accelerate operation speed of DSP and decrease the executing code. At the same time, proper address is assigned for each memory, which has different speed;the memory structure is also optimized. In addition, this system uses plenty of Extended Direct Memory Access (EDMA) to transport and process image data, which results in stable and high performance.
Dual Temporal Scale Convolutional Neural Network for Micro-Expression Recognition
Peng, Min; Wang, Chongyang; Chen, Tong; Liu, Guangyuan; Fu, Xiaolan
2017-01-01
Facial micro-expression is a brief involuntary facial movement and can reveal the genuine emotion that people try to conceal. Traditional methods of spontaneous micro-expression recognition rely excessively on sophisticated hand-crafted feature design and the recognition rate is not high enough for its practical application. In this paper, we proposed a Dual Temporal Scale Convolutional Neural Network (DTSCNN) for spontaneous micro-expressions recognition. The DTSCNN is a two-stream network. Different of stream of DTSCNN is used to adapt to different frame rate of micro-expression video clips. Each stream of DSTCNN consists of independent shallow network for avoiding the overfitting problem. Meanwhile, we fed the networks with optical-flow sequences to ensure that the shallow networks can further acquire higher-level features. Experimental results on spontaneous micro-expression databases (CASME I/II) showed that our method can achieve a recognition rate almost 10% higher than what some state-of-the-art method can achieve. PMID:29081753
Human body motion tracking based on quantum-inspired immune cloning algorithm
NASA Astrophysics Data System (ADS)
Han, Hong; Yue, Lichuan; Jiao, Licheng; Wu, Xing
2009-10-01
In a static monocular camera system, to gain a perfect 3D human body posture is a great challenge for Computer Vision technology now. This paper presented human postures recognition from video sequences using the Quantum-Inspired Immune Cloning Algorithm (QICA). The algorithm included three parts. Firstly, prior knowledge of human beings was used, the key joint points of human could be detected automatically from the human contours and skeletons which could be thinning from the contours; And due to the complexity of human movement, a forecasting mechanism of occlusion joint points was addressed to get optimum 2D key joint points of human body; And then pose estimation recovered by optimizing between the 2D projection of 3D human key joint points and 2D detection key joint points using QICA, which recovered the movement of human body perfectly, because this algorithm could acquire not only the global optimal solution, but the local optimal solution.
A bio-inspired system for spatio-temporal recognition in static and video imagery
NASA Astrophysics Data System (ADS)
Khosla, Deepak; Moore, Christopher K.; Chelian, Suhas
2007-04-01
This paper presents a bio-inspired method for spatio-temporal recognition in static and video imagery. It builds upon and extends our previous work on a bio-inspired Visual Attention and object Recognition System (VARS). The VARS approach locates and recognizes objects in a single frame. This work presents two extensions of VARS. The first extension is a Scene Recognition Engine (SCE) that learns to recognize spatial relationships between objects that compose a particular scene category in static imagery. This could be used for recognizing the category of a scene, e.g., office vs. kitchen scene. The second extension is the Event Recognition Engine (ERE) that recognizes spatio-temporal sequences or events in sequences. This extension uses a working memory model to recognize events and behaviors in video imagery by maintaining and recognizing ordered spatio-temporal sequences. The working memory model is based on an ARTSTORE1 neural network that combines an ART-based neural network with a cascade of sustained temporal order recurrent (STORE)1 neural networks. A series of Default ARTMAP classifiers ascribes event labels to these sequences. Our preliminary studies have shown that this extension is robust to variations in an object's motion profile. We evaluated the performance of the SCE and ERE on real datasets. The SCE module was tested on a visual scene classification task using the LabelMe2 dataset. The ERE was tested on real world video footage of vehicles and pedestrians in a street scene. Our system is able to recognize the events in this footage involving vehicles and pedestrians.
Integrated remotely sensed datasets for disaster management
NASA Astrophysics Data System (ADS)
McCarthy, Timothy; Farrell, Ronan; Curtis, Andrew; Fotheringham, A. Stewart
2008-10-01
Video imagery can be acquired from aerial, terrestrial and marine based platforms and has been exploited for a range of remote sensing applications over the past two decades. Examples include coastal surveys using aerial video, routecorridor infrastructures surveys using vehicle mounted video cameras, aerial surveys over forestry and agriculture, underwater habitat mapping and disaster management. Many of these video systems are based on interlaced, television standards such as North America's NTSC and European SECAM and PAL television systems that are then recorded using various video formats. This technology has recently being employed as a front-line, remote sensing technology for damage assessment post-disaster. This paper traces the development of spatial video as a remote sensing tool from the early 1980s to the present day. The background to a new spatial-video research initiative based at National University of Ireland, Maynooth, (NUIM) is described. New improvements are proposed and include; low-cost encoders, easy to use software decoders, timing issues and interoperability. These developments will enable specialists and non-specialists collect, process and integrate these datasets within minimal support. This integrated approach will enable decision makers to access relevant remotely sensed datasets quickly and so, carry out rapid damage assessment during and post-disaster.
Validation of a Video-based Game-Understanding Test Procedure in Badminton.
ERIC Educational Resources Information Center
Blomqvist, Minna T.; Luhtanen, Pekka; Laakso, Lauri; Keskinen, Esko
2000-01-01
Reports the development and validation of video-based game-understanding tests in badminton for elementary and secondary students. The tests included different sequences that simulated actual game situations. Players had to solve tactical problems by selecting appropriate solutions and arguments for their decisions. Results suggest that the test…
Aquatic Toxic Analysis by Monitoring Fish Behavior Using Computer Vision: A Recent Progress
Fu, Longwen; Liu, Zuoyi
2018-01-01
Video tracking based biological early warning system achieved a great progress with advanced computer vision and machine learning methods. Ability of video tracking of multiple biological organisms has been largely improved in recent years. Video based behavioral monitoring has become a common tool for acquiring quantified behavioral data for aquatic risk assessment. Investigation of behavioral responses under chemical and environmental stress has been boosted by rapidly developed machine learning and artificial intelligence. In this paper, we introduce the fundamental of video tracking and present the pioneer works in precise tracking of a group of individuals in 2D and 3D space. Technical and practical issues suffered in video tracking are explained. Subsequently, the toxic analysis based on fish behavioral data is summarized. Frequently used computational methods and machine learning are explained with their applications in aquatic toxicity detection and abnormal pattern analysis. Finally, advantages of recent developed deep learning approach in toxic prediction are presented. PMID:29849612
NASA Astrophysics Data System (ADS)
Shimada, Satoshi; Azuma, Shouzou; Teranaka, Sayaka; Kojima, Akira; Majima, Yukie; Maekawa, Yasuko
We developed the system that knowledge could be discovered and shared cooperatively in the organization based on the SECI model of knowledge management. This system realized three processes by the following method. (1)A video that expressed skill is segmented into a number of scenes according to its contents. Tacit knowledge is shared in each scene. (2)Tacit knowledge is extracted by bulletin board linked to each scene. (3)Knowledge is acquired by repeatedly viewing the video scene with the comment that shows the technical content to be practiced. We conducted experiments that the system was used by nurses working for general hospitals. Experimental results show that the nursing practical knack is able to be collected by utilizing bulletin board linked to video scene. Results of this study confirmed the possibility of expressing the tacit knowledge of nurses' empirical nursing skills sensitively with a clue of video images.
Multi-Sensor Fusion and Enhancement for Object Detection
NASA Technical Reports Server (NTRS)
Rahman, Zia-Ur
2005-01-01
This was a quick &week effort to investigate the ability to detect changes along the flight path of an unmanned airborne vehicle (UAV) over time. Video was acquired by the UAV during several passes over the same terrain. Concurrently, GPS data and UAV attitude data were also acquired. The purpose of the research was to use information from all of these sources to detect if any change had occurred in the terrain encompassed by the flight path.
NASA Astrophysics Data System (ADS)
Zhang, Xunxun; Xu, Hongke; Fang, Jianwu
2018-01-01
Along with the rapid development of the unmanned aerial vehicle technology, multiple vehicle tracking (MVT) in aerial video sequence has received widespread interest for providing the required traffic information. Due to the camera motion and complex background, MVT in aerial video sequence poses unique challenges. We propose an efficient MVT algorithm via driver behavior-based Kalman filter (DBKF) and an improved deterministic data association (IDDA) method. First, a hierarchical image registration method is put forward to compensate the camera motion. Afterward, to improve the accuracy of the state estimation, we propose the DBKF module by incorporating the driver behavior into the Kalman filter, where artificial potential field is introduced to reflect the driver behavior. Then, to implement the data association, a local optimization method is designed instead of global optimization. By introducing the adaptive operating strategy, the proposed IDDA method can also deal with the situation in which the vehicles suddenly appear or disappear. Finally, comprehensive experiments on the DARPA VIVID data set and KIT AIS data set demonstrate that the proposed algorithm can generate satisfactory and superior results.
Recognition of Indian Sign Language in Live Video
NASA Astrophysics Data System (ADS)
Singha, Joyeeta; Das, Karen
2013-05-01
Sign Language Recognition has emerged as one of the important area of research in Computer Vision. The difficulty faced by the researchers is that the instances of signs vary with both motion and appearance. Thus, in this paper a novel approach for recognizing various alphabets of Indian Sign Language is proposed where continuous video sequences of the signs have been considered. The proposed system comprises of three stages: Preprocessing stage, Feature Extraction and Classification. Preprocessing stage includes skin filtering, histogram matching. Eigen values and Eigen Vectors were considered for feature extraction stage and finally Eigen value weighted Euclidean distance is used to recognize the sign. It deals with bare hands, thus allowing the user to interact with the system in natural way. We have considered 24 different alphabets in the video sequences and attained a success rate of 96.25%.
Variable disparity-motion estimation based fast three-view video coding
NASA Astrophysics Data System (ADS)
Bae, Kyung-Hoon; Kim, Seung-Cheol; Hwang, Yong Seok; Kim, Eun-Soo
2009-02-01
In this paper, variable disparity-motion estimation (VDME) based 3-view video coding is proposed. In the encoding, key-frame coding (KFC) based motion estimation and variable disparity estimation (VDE) for effectively fast three-view video encoding are processed. These proposed algorithms enhance the performance of 3-D video encoding/decoding system in terms of accuracy of disparity estimation and computational overhead. From some experiments, stereo sequences of 'Pot Plant' and 'IVO', it is shown that the proposed algorithm's PSNRs is 37.66 and 40.55 dB, and the processing time is 0.139 and 0.124 sec/frame, respectively.
Application of M-JPEG compression hardware to dynamic stimulus production.
Mulligan, J B
1997-01-01
Inexpensive circuit boards have appeared on the market which transform a normal micro-computer's disk drive into a video disk capable of playing extended video sequences in real time. This technology enables the performance of experiments which were previously impossible, or at least prohibitively expensive. The new technology achieves this capability using special-purpose hardware to compress and decompress individual video frames, enabling a video stream to be transferred over relatively low-bandwidth disk interfaces. This paper will describe the use of such devices for visual psychophysics and present the technical issues that must be considered when evaluating individual products.
Impact of an Active Video Game on Healthy Children’s Physical Activity
Abdelsamad, Dina; Baranowski, Janice; O’Connor, Teresia Margareta; Thompson, Debbe; Barnett, Anthony; Cerin, Ester; Chen, Tzu-An
2012-01-01
OBJECTIVE: This naturalistic study tests whether children receiving a new (to them) active video game spontaneously engage in more physical activity than those receiving an inactive video game, and whether the effect would be greater among children in unsafe neighborhoods, who might not be allowed to play outside. METHODS: Participants were children 9 to 12 years of age, with a BMI >50th percentile, but <99th percentile; none of these children a medical condition that would preclude physical activity or playing video games. A randomized clinical trial assigned children to receiving 2 active or 2 inactive video games, the peripherals necessary to run the games, and a Wii console. Physical activity was monitored by using accelerometers for 5 weeks over the course of a 13-week experiment. Neighborhood safety was assessed with a 12 item validated questionnaire. RESULTS: There was no evidence that children receiving the active video games were more active in general, or at anytime, than children receiving the inactive video games. The outcomes were not moderated by parent perceived neighborhood safety, child BMI z score, or other demographic characteristics. CONCLUSIONS: These results provide no reason to believe that simply acquiring an active video game under naturalistic circumstances provides a public health benefit to children. PMID:22371457
Selecting salient frames for spatiotemporal video modeling and segmentation.
Song, Xiaomu; Fan, Guoliang
2007-12-01
We propose a new statistical generative model for spatiotemporal video segmentation. The objective is to partition a video sequence into homogeneous segments that can be used as "building blocks" for semantic video segmentation. The baseline framework is a Gaussian mixture model (GMM)-based video modeling approach that involves a six-dimensional spatiotemporal feature space. Specifically, we introduce the concept of frame saliency to quantify the relevancy of a video frame to the GMM-based spatiotemporal video modeling. This helps us use a small set of salient frames to facilitate the model training by reducing data redundancy and irrelevance. A modified expectation maximization algorithm is developed for simultaneous GMM training and frame saliency estimation, and the frames with the highest saliency values are extracted to refine the GMM estimation for video segmentation. Moreover, it is interesting to find that frame saliency can imply some object behaviors. This makes the proposed method also applicable to other frame-related video analysis tasks, such as key-frame extraction, video skimming, etc. Experiments on real videos demonstrate the effectiveness and efficiency of the proposed method.
A no-reference image and video visual quality metric based on machine learning
NASA Astrophysics Data System (ADS)
Frantc, Vladimir; Voronin, Viacheslav; Semenishchev, Evgenii; Minkin, Maxim; Delov, Aliy
2018-04-01
The paper presents a novel visual quality metric for lossy compressed video quality assessment. High degree of correlation with subjective estimations of quality is due to using of a convolutional neural network trained on a large amount of pairs video sequence-subjective quality score. We demonstrate how our predicted no-reference quality metric correlates with qualitative opinion in a human observer study. Results are shown on the EVVQ dataset with comparison existing approaches.
NASA Astrophysics Data System (ADS)
Gohatre, Umakant Bhaskar; Patil, Venkat P.
2018-04-01
In computer vision application, the multiple object detection and tracking, in real-time operation is one of the important research field, that have gained a lot of attentions, in last few years for finding non stationary entities in the field of image sequence. The detection of object is advance towards following the moving object in video and then representation of object is step to track. The multiple object recognition proof is one of the testing assignment from detection multiple objects from video sequence. The picture enrollment has been for quite some time utilized as a reason for the location the detection of moving multiple objects. The technique of registration to discover correspondence between back to back casing sets in view of picture appearance under inflexible and relative change. The picture enrollment is not appropriate to deal with event occasion that can be result in potential missed objects. In this paper, for address such problems, designs propose novel approach. The divided video outlines utilizing area adjancy diagram of visual appearance and geometric properties. Then it performed between graph sequences by using multi graph matching, then getting matching region labeling by a proposed graph coloring algorithms which assign foreground label to respective region. The plan design is robust to unknown transformation with significant improvement in overall existing work which is related to moving multiple objects detection in real time parameters.
NASA Astrophysics Data System (ADS)
Adedayo, Bada; Wang, Qi; Alcaraz Calero, Jose M.; Grecos, Christos
2015-02-01
The recent explosion in video-related Internet traffic has been driven by the widespread use of smart mobile devices, particularly smartphones with advanced cameras that are able to record high-quality videos. Although many of these devices offer the facility to record videos at different spatial and temporal resolutions, primarily with local storage considerations in mind, most users only ever use the highest quality settings. The vast majority of these devices are optimised for compressing the acquired video using a single built-in codec and have neither the computational resources nor battery reserves to transcode the video to alternative formats. This paper proposes a new low-complexity dynamic resource allocation engine for cloud-based video transcoding services that are both scalable and capable of being delivered in real-time. Firstly, through extensive experimentation, we establish resource requirement benchmarks for a wide range of transcoding tasks. The set of tasks investigated covers the most widely used input formats (encoder type, resolution, amount of motion and frame rate) associated with mobile devices and the most popular output formats derived from a comprehensive set of use cases, e.g. a mobile news reporter directly transmitting videos to the TV audience of various video format requirements, with minimal usage of resources both at the reporter's end and at the cloud infrastructure end for transcoding services.
An Imaging And Graphics Workstation For Image Sequence Analysis
NASA Astrophysics Data System (ADS)
Mostafavi, Hassan
1990-01-01
This paper describes an application-specific engineering workstation designed and developed to analyze imagery sequences from a variety of sources. The system combines the software and hardware environment of the modern graphic-oriented workstations with the digital image acquisition, processing and display techniques. The objective is to achieve automation and high throughput for many data reduction tasks involving metric studies of image sequences. The applications of such an automated data reduction tool include analysis of the trajectory and attitude of aircraft, missile, stores and other flying objects in various flight regimes including launch and separation as well as regular flight maneuvers. The workstation can also be used in an on-line or off-line mode to study three-dimensional motion of aircraft models in simulated flight conditions such as wind tunnels. The system's key features are: 1) Acquisition and storage of image sequences by digitizing real-time video or frames from a film strip; 2) computer-controlled movie loop playback, slow motion and freeze frame display combined with digital image sharpening, noise reduction, contrast enhancement and interactive image magnification; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored image sequence; 4) automatic and manual field-of-view and spatial calibration; 5) image sequence data base generation and management, including the measurement data products; 6) off-line analysis software for trajectory plotting and statistical analysis; 7) model-based estimation and tracking of object attitude angles; and 8) interface to a variety of video players and film transport sub-systems.
Anchor Node Localization for Wireless Sensor Networks Using Video and Compass Information Fusion
Pescaru, Dan; Curiac, Daniel-Ioan
2014-01-01
Distributed sensing, computing and communication capabilities of wireless sensor networks require, in most situations, an efficient node localization procedure. In the case of random deployments in harsh or hostile environments, a general localization process within global coordinates is based on a set of anchor nodes able to determine their own position using GPS receivers. In this paper we propose another anchor node localization technique that can be used when GPS devices cannot accomplish their mission or are considered to be too expensive. This novel technique is based on the fusion of video and compass data acquired by the anchor nodes and is especially suitable for video- or multimedia-based wireless sensor networks. For these types of wireless networks the presence of video cameras is intrinsic, while the presence of digital compasses is also required for identifying the cameras' orientations. PMID:24594614
Video Imaging System Particularly Suited for Dynamic Gear Inspection
NASA Technical Reports Server (NTRS)
Broughton, Howard (Inventor)
1999-01-01
A digital video imaging system that captures the image of a single tooth of interest of a rotating gear is disclosed. The video imaging system detects the complete rotation of the gear and divide that rotation into discrete time intervals so that each tooth of interest of the gear is precisely determined when it is at a desired location that is illuminated in unison with a digital video camera so as to record a single digital image for each tooth. The digital images are available to provide instantaneous analysis of the tooth of interest, or to be stored and later provide images that yield a history that may be used to predict gear failure, such as gear fatigue. The imaging system is completely automated by a controlling program so that it may run for several days acquiring images without supervision from the user.
Getting the Bigger Picture With Digital Surveillance
NASA Technical Reports Server (NTRS)
2002-01-01
Through a Space Act Agreement, Diebold, Inc., acquired the exclusive rights to Glenn Research Center's patented video observation technology, originally designed to accelerate video image analysis for various ongoing and future space applications. Diebold implemented the technology into its AccuTrack digital, color video recorder, a state-of- the-art surveillance product that uses motion detection for around-the- clock monitoring. AccuTrack captures digitally signed images and transaction data in real-time. This process replaces the onerous tasks involved in operating a VCR-based surveillance system, and subsequently eliminates the need for central viewing and tape archiving locations altogether. AccuTrack can monitor an entire bank facility, including four automated teller machines, multiple teller lines, and new account areas, all from one central location.
Video Analysis in Cross-Cultural Environments and Methodological Issues
ERIC Educational Resources Information Center
Montandon, Christiane
2015-01-01
This paper addresses the use of videography combined with group interviews, as a way to better understand the informal learnings of 11-12 year old children in cross-cultural encounters during French-German school exchanges. The complete, consistent video data required the researchers to choose the most significant sequences to highlight the…
ERIC Educational Resources Information Center
Martin, James E.; And Others
1992-01-01
This study examined the effects of two indirect corrective feedback procedures (picture and video referencing involving instructor prompting) on the assembly skills of five secondary students with moderate mental retardation. Picture and video referencing conditions were more effective than assembly photographs, sequenced pictures, sequenced…
NASA Astrophysics Data System (ADS)
Kushwaha, Alok Kumar Singh; Srivastava, Rajeev
2015-09-01
An efficient view invariant framework for the recognition of human activities from an input video sequence is presented. The proposed framework is composed of three consecutive modules: (i) detect and locate people by background subtraction, (ii) view invariant spatiotemporal template creation for different activities, (iii) and finally, template matching is performed for view invariant activity recognition. The foreground objects present in a scene are extracted using change detection and background modeling. The view invariant templates are constructed using the motion history images and object shape information for different human activities in a video sequence. For matching the spatiotemporal templates for various activities, the moment invariants and Mahalanobis distance are used. The proposed approach is tested successfully on our own viewpoint dataset, KTH action recognition dataset, i3DPost multiview dataset, MSR viewpoint action dataset, VideoWeb multiview dataset, and WVU multiview human action recognition dataset. From the experimental results and analysis over the chosen datasets, it is observed that the proposed framework is robust, flexible, and efficient with respect to multiple views activity recognition, scale, and phase variations.
Self-expressive Dictionary Learning for Dynamic 3D Reconstruction.
Zheng, Enliang; Ji, Dinghuang; Dunn, Enrique; Frahm, Jan-Michael
2017-08-22
We target the problem of sparse 3D reconstruction of dynamic objects observed by multiple unsynchronized video cameras with unknown temporal overlap. To this end, we develop a framework to recover the unknown structure without sequencing information across video sequences. Our proposed compressed sensing framework poses the estimation of 3D structure as the problem of dictionary learning, where the dictionary is defined as an aggregation of the temporally varying 3D structures. Given the smooth motion of dynamic objects, we observe any element in the dictionary can be well approximated by a sparse linear combination of other elements in the same dictionary (i.e. self-expression). Our formulation optimizes a biconvex cost function that leverages a compressed sensing formulation and enforces both structural dependency coherence across video streams, as well as motion smoothness across estimates from common video sources. We further analyze the reconstructability of our approach under different capture scenarios, and its comparison and relation to existing methods. Experimental results on large amounts of synthetic data as well as real imagery demonstrate the effectiveness of our approach.
Thompson, Joseph J; McColeman, C M; Stepanova, Ekaterina R; Blair, Mark R
2017-04-01
Many theories of complex cognitive-motor skill learning are built on the notion that basic cognitive processes group actions into easy-to-perform sequences. The present work examines predictions derived from laboratory-based studies of motor chunking and motor preparation using data collected from the real-time strategy video game StarCraft 2. We examined 996,163 action sequences in the telemetry data of 3,317 players across seven levels of skill. As predicted, the latency to the first action (thought to be the beginning of a chunked sequence) is delayed relative to the other actions in the group. Other predictions, inspired by the memory drum theory of Henry and Rogers, received only weak support. Copyright © 2017 Cognitive Science Society, Inc.
Estimation of velocities via optical flow
NASA Astrophysics Data System (ADS)
Popov, A.; Miller, A.; Miller, B.; Stepanyan, K.
2017-02-01
This article presents an approach to the optical flow (OF) usage as a general navigation means providing the information about the linear and angular vehicle's velocities. The term of "OF" came from opto-electronic devices where it corresponds to a video sequence of images related to the camera motion either over static surfaces or set of objects. Even if the positions of these objects are unknown in advance, one can estimate the camera motion provided just by video sequence itself and some metric information, such as distance between the objects or the range to the surface. This approach is applicable to any passive observation system which is able to produce a sequence of images, such as radio locator or sonar. Here the UAV application of the OF is considered since it is historically
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shepard, A; Matrosic, C; Zagzebski, J
Purpose: To develop an advanced testbed that combines a 3D motion stage and ultrasound phantom to optimize and validate 2D and 3D tracking algorithms for real-time motion management during radiation therapy. Methods: A Siemens S2000 Ultrasound scanner utilizing a 9L4 transducer was coupled with the Washington University 4D Phantom to simulate patient motion. The transducer was securely fastened to the 3D stage and positioned to image three cylinders of varying contrast in a Gammex 404GS LE phantom. The transducer was placed within a water bath above the phantom in order to maintain sufficient coupling for the entire range of simulatedmore » motion. A programmed motion sequence was used to move the transducer during image acquisition and a cine video was acquired for one minute to allow for long sequence tracking. Images were analyzed using a normalized cross-correlation block matching tracking algorithm and compared to the known motion of the transducer relative to the phantom. Results: The setup produced stable ultrasound motion traces consistent with those programmed into the 3D motion stage. The acquired ultrasound images showed minimal artifacts and an image quality that was more than suitable for tracking algorithm verification. Comparisons of a block matching tracking algorithm with the known motion trace for the three features resulted in an average tracking error of 0.59 mm. Conclusion: The high accuracy and programmability of the 4D phantom allows for the acquisition of ultrasound motion sequences that are highly customizable; allowing for focused analysis of some common pitfalls of tracking algorithms such as partial feature occlusion or feature disappearance, among others. The design can easily be modified to adapt to any probe such that the process can be extended to 3D acquisition. Further development of an anatomy specific phantom better resembling true anatomical landmarks could lead to an even more robust validation. This work is partially funded by NIH grant R01CA190298.« less
Image sequence analysis workstation for multipoint motion analysis
NASA Astrophysics Data System (ADS)
Mostafavi, Hassan
1990-08-01
This paper describes an application-specific engineering workstation designed and developed to analyze motion of objects from video sequences. The system combines the software and hardware environment of a modem graphic-oriented workstation with the digital image acquisition, processing and display techniques. In addition to automation and Increase In throughput of data reduction tasks, the objective of the system Is to provide less invasive methods of measurement by offering the ability to track objects that are more complex than reflective markers. Grey level Image processing and spatial/temporal adaptation of the processing parameters is used for location and tracking of more complex features of objects under uncontrolled lighting and background conditions. The applications of such an automated and noninvasive measurement tool include analysis of the trajectory and attitude of rigid bodies such as human limbs, robots, aircraft in flight, etc. The system's key features are: 1) Acquisition and storage of Image sequences by digitizing and storing real-time video; 2) computer-controlled movie loop playback, freeze frame display, and digital Image enhancement; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored Image sequence; 4) model-based estimation and tracking of the six degrees of freedom of a rigid body: 5) field-of-view and spatial calibration: 6) Image sequence and measurement data base management; and 7) offline analysis software for trajectory plotting and statistical analysis.
Chess-playing epilepsy: a case report with video-EEG and back averaging.
Mann, M W; Gueguen, B; Guillou, S; Debrand, E; Soufflet, C
2004-12-01
A patient suffering from juvenile myoclonic epilepsy experienced myoclonic jerks, fairly regularly, while playing chess. The myoclonus appeared particularly when he had to plan his strategy, to choose between two solutions or while raising the arm to move a chess figure. Video-EEG-polygraphy was performed, with back averaging of the myoclonus registered during a chess match and during neuropsychological testing with Kohs cubes. The EEG spike wave complexes were localised in the fronto-central region. [Published with video sequences].
Video enhancement method with color-protection post-processing
NASA Astrophysics Data System (ADS)
Kim, Youn Jin; Kwak, Youngshin
2015-01-01
The current study is aimed to propose a post-processing method for video enhancement by adopting a color-protection technique. The color-protection intends to attenuate perceptible artifacts due to over-enhancements in visually sensitive image regions such as low-chroma colors, including skin and gray objects. In addition, reducing the loss in color texture caused by the out-of-color-gamut signals is also taken into account. Consequently, color reproducibility of video sequences could be remarkably enhanced while the undesirable visual exaggerations are minimized.
Performance analysis of medical video streaming over mobile WiMAX.
Alinejad, Ali; Philip, N; Istepanian, R H
2010-01-01
Wireless medical ultrasound streaming is considered one of the emerging application within the broadband mobile healthcare domain. These applications are considered as bandwidth demanding services that required high data rates with acceptable diagnostic quality of the transmitted medical images. In this paper, we present the performance analysis of a medical ultrasound video streaming acquired via special robotic ultrasonography system over emulated WiMAX wireless network. The experimental set-up of this application is described together with the performance of the relevant medical quality of service (m-QoS) metrics.
Embed dynamic content in your poster.
Hutchins, B Ian
2013-01-29
A new technology has emerged that will facilitate the presentation of dynamic or otherwise inaccessible data on posters at scientific meetings. Video, audio, or other digital files hosted on mobile-friendly sites can be linked to through a quick response (QR) code, a two-dimensional barcode that can be scanned by smartphones, which then display the content. This approach is more affordable than acquiring tablet computers for playing dynamic content and can reach many users at large conferences. This resource details how to host videos, generate QR codes, and view the associated files on mobile devices.
Highly Protable Airborne Multispectral Imaging System
NASA Technical Reports Server (NTRS)
Lehnemann, Robert; Mcnamee, Todd
2001-01-01
A portable instrumentation system is described that includes and airborne and a ground-based subsytem. It can acquire multispectral image data over swaths of terrain ranging in width from about 1.5 to 1 km. The system was developed especially for use in coastal environments and is well suited for performing remote sensing and general environmental monitoring. It includes a small,munpilotaed, remotely controlled airplance that carries a forward-looking camera for navigation, three downward-looking monochrome video cameras for imaging terrain in three spectral bands, a video transmitter, and a Global Positioning System (GPS) reciever.
The recovery and utilization of space suit range-of-motion data
NASA Technical Reports Server (NTRS)
Reinhardt, AL; Walton, James S.
1988-01-01
A technique for recovering data for the range of motion of a subject wearing a space suit is described along with the validation of this technique on an EVA space suit. Digitized data are automatically acquired from video images of the subject; three-dimensional trajectories are recovered from these data, and can be displayed using three-dimensional computer graphics. Target locations are recovered using a unique video processor and close-range photogrammetry. It is concluded that such data can be used in such applications as the animation of anthropometric computer models.
About subjective evaluation of adaptive video streaming
NASA Astrophysics Data System (ADS)
Tavakoli, Samira; Brunnström, Kjell; Garcia, Narciso
2015-03-01
The usage of HTTP Adaptive Streaming (HAS) technology by content providers is increasing rapidly. Having available the video content in multiple qualities, using HAS allows to adapt the quality of downloaded video to the current network conditions providing smooth video-playback. However, the time-varying video quality by itself introduces a new type of impairment. The quality adaptation can be done in different ways. In order to find the best adaptation strategy maximizing users perceptual quality it is necessary to investigate about the subjective perception of adaptation-related impairments. However, the novelties of these impairments and their comparably long time duration make most of the standardized assessment methodologies fall less suited for studying HAS degradation. Furthermore, in traditional testing methodologies, the quality of the video in audiovisual services is often evaluated separated and not in the presence of audio. Nevertheless, the requirement of jointly evaluating the audio and the video within a subjective test is a relatively under-explored research field. In this work, we address the research question of determining the appropriate assessment methodology to evaluate the sequences with time-varying quality due to the adaptation. This was done by studying the influence of different adaptation related parameters through two different subjective experiments using a methodology developed to evaluate long test sequences. In order to study the impact of audio presence on quality assessment by the test subjects, one of the experiments was done in the presence of audio stimuli. The experimental results were subsequently compared with another experiment using the standardized single stimulus Absolute Category Rating (ACR) methodology.
[An fMRI study on brain activation patterns of males and females during video sexual stimulation].
Yang, Bo; Zhang, Jin-shan; Wang, Tao; Zhou, Yi-cheng; Liu, Ji-hong; Ma, Lin
2007-08-01
To investigate the difference in the brain activation patterns of males and females during video sexual stimulation by functional magnetic resonance imaging (fMRI). The participants were 20 adult males and 20 adult females, all healthy, right-handed, and with no history of sexual function disorder and physical, psychiatric or neurological diseases. Blood-oxygen-level-dependent fMRI was performed using a 1.5 T MR scanner. Three-dimensional anatomical image of the entire brain were obtained by using a T1-weighted three-dimensional anatomical image spoiled gradient echo pulse sequence. Each person was shown neutral and erotic video sequences for 60 s each in a block-study fashion, i.e. neutral scenes--erotic scenes--neutral scenes, and so on. The total scanning time was approximately 7 minutes, with a 12 s interval between two subsequent video sequences in order to avoid any overlapping between erotic and neutral information. The video sexual stimulation produced different results in the men and women. The females showed activation both in the left and the right amygdala, greater in the former than in the latter ([220.52 +/- 17.09] mm3 vs. [155.45 +/- 18.34] mm3, P < 0.05), but in the males only the left amygdala was activated. The males showed greater brain activation than the females in the left anterior cingulate gyrus ([420.75 +/- 19.37] mm3 vs. [310.67 +/- 10.53] mm3, P < 0.05), but less than the females in the splenium of the corpus callosum ([363.32 +/- 13.30] mm3 vs. [473.45 +/- 14.92] mm3, P < 0.01). Brain activation patterns of males and females during video sexual stimulation are different, underlying which is presumably the difference in both the structure and function of the brain between men and women.
3D video coding: an overview of present and upcoming standards
NASA Astrophysics Data System (ADS)
Merkle, Philipp; Müller, Karsten; Wiegand, Thomas
2010-07-01
An overview of existing and upcoming 3D video coding standards is given. Various different 3D video formats are available, each with individual pros and cons. The 3D video formats can be separated into two classes: video-only formats (such as stereo and multiview video) and depth-enhanced formats (such as video plus depth and multiview video plus depth). Since all these formats exist of at least two video sequences and possibly additional depth data, efficient compression is essential for the success of 3D video applications and technologies. For the video-only formats the H.264 family of coding standards already provides efficient and widely established compression algorithms: H.264/AVC simulcast, H.264/AVC stereo SEI message, and H.264/MVC. For the depth-enhanced formats standardized coding algorithms are currently being developed. New and specially adapted coding approaches are necessary, as the depth or disparity information included in these formats has significantly different characteristics than video and is not displayed directly, but used for rendering. Motivated by evolving market needs, MPEG has started an activity to develop a generic 3D video standard within the 3DVC ad-hoc group. Key features of the standard are efficient and flexible compression of depth-enhanced 3D video representations and decoupling of content creation and display requirements.
Shadow Detection Based on Regions of Light Sources for Object Extraction in Nighttime Video
Lee, Gil-beom; Lee, Myeong-jin; Lee, Woo-Kyung; Park, Joo-heon; Kim, Tae-Hwan
2017-01-01
Intelligent video surveillance systems detect pre-configured surveillance events through background modeling, foreground and object extraction, object tracking, and event detection. Shadow regions inside video frames sometimes appear as foreground objects, interfere with ensuing processes, and finally degrade the event detection performance of the systems. Conventional studies have mostly used intensity, color, texture, and geometric information to perform shadow detection in daytime video, but these methods lack the capability of removing shadows in nighttime video. In this paper, a novel shadow detection algorithm for nighttime video is proposed; this algorithm partitions each foreground object based on the object’s vertical histogram and screens out shadow objects by validating their orientations heading toward regions of light sources. From the experimental results, it can be seen that the proposed algorithm shows more than 93.8% shadow removal and 89.9% object extraction rates for nighttime video sequences, and the algorithm outperforms conventional shadow removal algorithms designed for daytime videos. PMID:28327515
Markerless video analysis for movement quantification in pediatric epilepsy monitoring.
Lu, Haiping; Eng, How-Lung; Mandal, Bappaditya; Chan, Derrick W S; Ng, Yen-Ling
2011-01-01
This paper proposes a markerless video analytic system for quantifying body part movements in pediatric epilepsy monitoring. The system utilizes colored pajamas worn by a patient in bed to extract body part movement trajectories, from which various features can be obtained for seizure detection and analysis. Hence, it is non-intrusive and it requires no sensor/marker to be attached to the patient's body. It takes raw video sequences as input and a simple user-initialization indicates the body parts to be examined. In background/foreground modeling, Gaussian mixture models are employed in conjunction with HSV-based modeling. Body part detection follows a coarse-to-fine paradigm with graph-cut-based segmentation. Finally, body part parameters are estimated with domain knowledge guidance. Experimental studies are reported on sequences captured in an Epilepsy Monitoring Unit at a local hospital. The results demonstrate the feasibility of the proposed system in pediatric epilepsy monitoring and seizure detection.
Automated 3D trajectory measuring of large numbers of moving particles.
Wu, Hai Shan; Zhao, Qi; Zou, Danping; Chen, Yan Qiu
2011-04-11
Complex dynamics of natural particle systems, such as insect swarms, bird flocks, fish schools, has attracted great attention of scientists for years. Measuring 3D trajectory of each individual in a group is vital for quantitative study of their dynamic properties, yet such empirical data is rare mainly due to the challenges of maintaining the identities of large numbers of individuals with similar visual features and frequent occlusions. We here present an automatic and efficient algorithm to track 3D motion trajectories of large numbers of moving particles using two video cameras. Our method solves this problem by formulating it as three linear assignment problems (LAP). For each video sequence, the first LAP obtains 2D tracks of moving targets and is able to maintain target identities in the presence of occlusions; the second one matches the visually similar targets across two views via a novel technique named maximum epipolar co-motion length (MECL), which is not only able to effectively reduce matching ambiguity but also further diminish the influence of frequent occlusions; the last one links 3D track segments into complete trajectories via computing a globally optimal assignment based on temporal and kinematic cues. Experiment results on simulated particle swarms with various particle densities validated the accuracy and robustness of the proposed method. As real-world case, our method successfully acquired 3D flight paths of fruit fly (Drosophila melanogaster) group comprising hundreds of freely flying individuals. © 2011 Optical Society of America
A deep learning pipeline for Indian dance style classification
NASA Astrophysics Data System (ADS)
Dewan, Swati; Agarwal, Shubham; Singh, Navjyoti
2018-04-01
In this paper, we address the problem of dance style classification to classify Indian dance or any dance in general. We propose a 3-step deep learning pipeline. First, we extract 14 essential joint locations of the dancer from each video frame, this helps us to derive any body region location within the frame, we use this in the second step which forms the main part of our pipeline. Here, we divide the dancer into regions of important motion in each video frame. We then extract patches centered at these regions. Main discriminative motion is captured in these patches. We stack the features from all such patches of a frame into a single vector and form our hierarchical dance pose descriptor. Finally, in the third step, we build a high level representation of the dance video using the hierarchical descriptors and train it using a Recurrent Neural Network (RNN) for classification. Our novelty also lies in the way we use multiple representations for a single video. This helps us to: (1) Overcome the RNN limitation of learning small sequences over big sequences such as dance; (2) Extract more data from the available dataset for effective deep learning by training multiple representations. Our contributions in this paper are three-folds: (1) We provide a deep learning pipeline for classification of any form of dance; (2) We prove that a segmented representation of a dance video works well with sequence learning techniques for recognition purposes; (3) We extend and refine the ICD dataset and provide a new dataset for evaluation of dance. Our model performs comparable or better in some cases than the state-of-the-art on action recognition benchmarks.
Video and LAN solutions for a digital OR: the Varese experience
NASA Astrophysics Data System (ADS)
Nocco, Umberto; Cocozza, Eugenio; Sivo, Monica; Peta, Giancarlo
2007-03-01
Purpose: build 20 ORs equipped with independent video acquisition and broadcasting systems and a powerful LAN connectivity. Methods: a digital PC controlled video matrix has been installed in each OR. The LAN connectivity has been developed to grant data entering the OR and high speed connectivity to a server and to broadcasting devices. Video signals are broadcasted within the OR. Fixed inputs and five additional video inputs have been placed in the OR. Images can be stored locally on a high capacity HDD and a DVD recorder. Images can be also stored in a central archive for future acquisition and reference. Ethernet plugs have been placed within the OR to acquire images and data from the Hospital LAN; the OR is connected to the server/archive using a dedicated optical fiber. Results: 20 independent digital ORs have been built. Each OR is "self contained" and images can be digitally managed and broadcasted. Security issues concerning both image visualization and electrical safety have been fulfilled and each OR is fully integrated in the Hospital LAN. Conclusions: Digital ORs were fully implemented, they fulfill surgeons needs in terms of video acquisition and distribution and grant high quality video for each kind of surgery in a major hospital.
Presentation of 3D Scenes Through Video Example.
Baldacci, Andrea; Ganovelli, Fabio; Corsini, Massimiliano; Scopigno, Roberto
2017-09-01
Using synthetic videos to present a 3D scene is a common requirement for architects, designers, engineers or Cultural Heritage professionals however it is usually time consuming and, in order to obtain high quality results, the support of a film maker/computer animation expert is necessary. We introduce an alternative approach that takes the 3D scene of interest and an example video as input, and automatically produces a video of the input scene that resembles the given video example. In other words, our algorithm allows the user to "replicate" an existing video, on a different 3D scene. We build on the intuition that a video sequence of a static environment is strongly characterized by its optical flow, or, in other words, that two videos are similar if their optical flows are similar. We therefore recast the problem as producing a video of the input scene whose optical flow is similar to the optical flow of the input video. Our intuition is supported by a user-study specifically designed to verify this statement. We have successfully tested our approach on several scenes and input videos, some of which are reported in the accompanying material of this paper.
Fernández-Aranda, Fernando; Jiménez-Murcia, Susana; Santamaría, Juan J; Gunnard, Katarina; Soto, Antonio; Kalapanidas, Elias; Bults, Richard G A; Davarakis, Costas; Ganchev, Todor; Granero, Roser; Konstantas, Dimitri; Kostoulas, Theodoros P; Lam, Tony; Lucas, Mikkel; Masuet-Aumatell, Cristina; Moussa, Maher H; Nielsen, Jeppe; Penelo, Eva
2012-08-01
Previous review studies have suggested that computer games can serve as an alternative or additional form of treatment in several areas (schizophrenia, asthma or motor rehabilitation). Although several naturalistic studies have been conducted showing the usefulness of serious video games in the treatment of some abnormal behaviours, there is a lack of serious games specially designed for treating mental disorders. The purpose of our project was to develop and evaluate a serious video game designed to remediate attitudinal, behavioural and emotional processes of patients with impulse-related disorders. The video game was created and developed within the European research project PlayMancer. It aims to prove potential capacity to change underlying attitudinal, behavioural and emotional processes of patients with impulse-related disorders. New interaction modes were provided by newly developed components, such as emotion recognition from speech, face and physiological reactions, while specific impulsive reactions were elicited. The video game uses biofeedback for helping patients to learn relaxation skills, acquire better self-control strategies and develop new emotional regulation strategies. In this article, we present a description of the video game used, rationale, user requirements, usability and preliminary data, in several mental disorders.
Enhanced visual short-term memory in action video game players.
Blacker, Kara J; Curby, Kim M
2013-08-01
Visual short-term memory (VSTM) is critical for acquiring visual knowledge and shows marked individual variability. Previous work has illustrated a VSTM advantage among action video game players (Boot et al. Acta Psychologica 129:387-398, 2008). A growing body of literature has suggested that action video game playing can bolster visual cognitive abilities in a domain-general manner, including abilities related to visual attention and the speed of processing, providing some potential bases for this VSTM advantage. In the present study, we investigated the VSTM advantage among video game players and assessed whether enhanced processing speed can account for this advantage. Experiment 1, using simple colored stimuli, revealed that action video game players demonstrate a similar VSTM advantage over nongamers, regardless of whether they are given limited or ample time to encode items into memory. Experiment 2, using complex shapes as the stimuli to increase the processing demands of the task, replicated this VSTM advantage, irrespective of encoding duration. These findings are inconsistent with a speed-of-processing account of this advantage. An alternative, attentional account, grounded in the existing literature on the visuo-cognitive consequences of video game play, is discussed.
T1 weighted fat/water separated PROPELLER acquired with dual bandwidths.
Rydén, Henric; Berglund, Johan; Norbeck, Ola; Avventi, Enrico; Skare, Stefan
2018-04-24
To describe a fat/water separated dual receiver bandwidth (rBW) spin echo PROPELLER sequence that eliminates the dead time associated with single rBW sequences. A nonuniform noise whitening by regularization of the fat/water inverse problem is proposed, to enable dual rBW reconstructions. Bipolar, flyback, and dual spin echo sequences were developed. All sequences acquire two echoes with different rBW without dead time. Chemical shift displacement was corrected by performing the fat/water separation in k-space, prior to gridding. The proposed sequences were compared to fat saturation, and single rBW sequences, in terms of SNR and CNR efficiency, using clinically relevant acquisition parameters. The impact of motion was investigated. Chemical shift correction greatly improved the image quality, especially at high resolution acquired with low rBW, and also improved motion estimates. SNR efficiency of the dual spin echo sequence was up to 20% higher than the single rBW acquisition, while CNR efficiency was 50% higher for the bipolar acquisition. Noise whitening was deemed necessary for all dual rBW acquisitions, rendering high image quality with strong and homogenous fat suppression. Dual rBW sequences eliminate the dead time present in single rBW sequences, which improves SNR efficiency. In combination with the proposed regularization, this enables highly efficient T1-weighted PROPELLER images without chemical shift displacement. © 2018 International Society for Magnetic Resonance in Medicine.
Prinz, A; Bolz, M; Findl, O
2005-11-01
Owing to the complex topographical aspects of ophthalmic surgery, teaching with conventional surgical videos has led to a poor understanding among medical students. A novel multimedia three dimensional (3D) computer animated program, called "Ophthalmic Operation Vienna" has been developed, where surgical videos are accompanied by 3D animated sequences of all surgical steps for five operations. The aim of the study was to assess the effect of 3D animations on the understanding of cataract and glaucoma surgery among medical students. Set in the Medical University of Vienna, Department of Ophthalmology, 172 students were randomised into two groups: a 3D group (n=90), that saw the 3D animations and video sequences, and a control group (n=82), that saw only the surgical videos. The narrated text was identical for both groups. After the presentation, students were questioned and tested using multiple choice questions. Students in the 3D group found the interactive multimedia teaching methods to be a valuable supplement to the conventional surgical videos. The 3D group outperformed the control group not only in topographical understanding by 16% (p<0.0001), but also in theoretical understanding by 7% (p<0.003). Women in the 3D group gained most by 19% over the control group (p<0.0001). The use of 3D animations lead to a better understanding of difficult surgical topics among medical students, especially for female users. Gender related benefits of using multimedia should be further explored.
NASA Astrophysics Data System (ADS)
Cicala, L.; Angelino, C. V.; Ruatta, G.; Baccaglini, E.; Raimondo, N.
2015-08-01
Unmanned Aerial Vehicles (UAVs) are often employed to collect high resolution images in order to perform image mosaicking and/or 3D reconstruction. Images are usually stored on board and then processed with on-ground desktop software. In such a way the computational load, and hence the power consumption, is moved on ground, leaving on board only the task of storing data. Such an approach is important in the case of small multi-rotorcraft UAVs because of their low endurance due to the short battery life. Images can be stored on board with either still image or video data compression. Still image system are preferred when low frame rates are involved, because video coding systems are based on motion estimation and compensation algorithms which fail when the motion vectors are significantly long and when the overlapping between subsequent frames is very small. In this scenario, UAVs attitude and position metadata from the Inertial Navigation System (INS) can be employed to estimate global motion parameters without video analysis. A low complexity image analysis can be still performed in order to refine the motion field estimated using only the metadata. In this work, we propose to use this refinement step in order to improve the position and attitude estimation produced by the navigation system in order to maximize the encoder performance. Experiments are performed on both simulated and real world video sequences.
Yakubova, Gulnoza; Hughes, Elizabeth M; Shinaberry, Megan
2016-07-01
The purpose of this study was to determine the effectiveness of a video modeling intervention with concrete-representational-abstract instructional sequence in teaching mathematics concepts to students with autism spectrum disorder (ASD). A multiple baseline across skills design of single-case experimental methodology was used to determine the effectiveness of the intervention on the acquisition and maintenance of addition, subtraction, and number comparison skills for four elementary school students with ASD. Findings supported the effectiveness of the intervention in improving skill acquisition and maintenance at a 3-week follow-up. Implications for practice and future research are discussed.
Qin, Lei; Snoussi, Hichem; Abdallah, Fahed
2014-01-01
We propose a novel approach for tracking an arbitrary object in video sequences for visual surveillance. The first contribution of this work is an automatic feature extraction method that is able to extract compact discriminative features from a feature pool before computing the region covariance descriptor. As the feature extraction method is adaptive to a specific object of interest, we refer to the region covariance descriptor computed using the extracted features as the adaptive covariance descriptor. The second contribution is to propose a weakly supervised method for updating the object appearance model during tracking. The method performs a mean-shift clustering procedure among the tracking result samples accumulated during a period of time and selects a group of reliable samples for updating the object appearance model. As such, the object appearance model is kept up-to-date and is prevented from contamination even in case of tracking mistakes. We conducted comparing experiments on real-world video sequences, which confirmed the effectiveness of the proposed approaches. The tracking system that integrates the adaptive covariance descriptor and the clustering-based model updating method accomplished stable object tracking on challenging video sequences. PMID:24865883
Dactyl Alphabet Gesture Recognition in a Video Sequence Using Microsoft Kinect
NASA Astrophysics Data System (ADS)
Artyukhin, S. G.; Mestetskiy, L. M.
2015-05-01
This paper presents an efficient framework for solving the problem of static gesture recognition based on data obtained from the web cameras and depth sensor Kinect (RGB-D - data). Each gesture given by a pair of images: color image and depth map. The database store gestures by it features description, genereated by frame for each gesture of the alphabet. Recognition algorithm takes as input a video sequence (a sequence of frames) for marking, put in correspondence with each frame sequence gesture from the database, or decide that there is no suitable gesture in the database. First, classification of the frame of the video sequence is done separately without interframe information. Then, a sequence of successful marked frames in equal gesture is grouped into a single static gesture. We propose a method combined segmentation of frame by depth map and RGB-image. The primary segmentation is based on the depth map. It gives information about the position and allows to get hands rough border. Then, based on the color image border is specified and performed analysis of the shape of the hand. Method of continuous skeleton is used to generate features. We propose a method of skeleton terminal branches, which gives the opportunity to determine the position of the fingers and wrist. Classification features for gesture is description of the position of the fingers relative to the wrist. The experiments were carried out with the developed algorithm on the example of the American Sign Language. American Sign Language gesture has several components, including the shape of the hand, its orientation in space and the type of movement. The accuracy of the proposed method is evaluated on the base of collected gestures consisting of 2700 frames.
De Ley, Paul; De Ley, Irma Tandingan; Morris, Krystalynne; Abebe, Eyualem; Mundo-Ocampo, Manuel; Yoder, Melissa; Heras, Joseph; Waumann, Dora; Rocha-Olivares, Axayácatl; Jay Burr, A.H; Baldwin, James G; Thomas, W. Kelley
2005-01-01
Molecular surveys of meiofaunal diversity face some interesting methodological challenges when it comes to interstitial nematodes from soils and sediments. Morphology-based surveys are greatly limited in processing speed, while barcoding approaches for nematodes are hampered by difficulties of matching sequence data with traditional taxonomy. Intermediate technology is needed to bridge the gap between both approaches. An example of such technology is video capture and editing microscopy, which consists of the recording of taxonomically informative multifocal series of microscopy images as digital video clips. The integration of multifocal imaging with sequence analysis of the D2D3 region of large subunit (LSU) rDNA is illustrated here in the context of a combined morphological and barcode sequencing survey of marine nematodes from Baja California and California. The resulting video clips and sequence data are made available online in the database NemATOL (http://nematol.unh.edu/). Analyses of 37 barcoded nematodes suggest that these represent at least 32 species, none of which matches available D2D3 sequences in public databases. The recorded multifocal vouchers allowed us to identify most specimens to genus, and will be used to match specimens with subsequent species identifications and descriptions of preserved specimens. Like molecular barcodes, multifocal voucher archives are part of a wider effort at structuring and changing the process of biodiversity discovery. We argue that data-rich surveys and phylogenetic tools for analysis of barcode sequences are an essential component of the exploration of phyla with a high fraction of undiscovered species. Our methods are also directly applicable to other meiofauna such as for example gastrotrichs and tardigrades. PMID:16214752
Haakma, Ineke; Janssen, Marleen; Minnaert, Alexander
2016-01-01
Because little is known about teacher-student relationships that involve students with acquired deafblindness, the authors performed a multiple case study with a multiple-method design to investigate the relationship between need-supportive teaching behaviors and student engagement. Using self-determination theory (Deci & Ryan, 2000), they analyzed video observations of interactions. It was found that teachers' provision of structure, autonomy support, and involvement often cooccurs with higher levels of student engagement. Moreover, varying degrees of need support over time seem to result in varying levels of student engagement. Examples are provided of need-supportive teaching behaviors that can be used to foster the motivation of students with acquired deafblindness.
Lip-reading enhancement for law enforcement
NASA Astrophysics Data System (ADS)
Theobald, Barry J.; Harvey, Richard; Cox, Stephen J.; Lewis, Colin; Owen, Gari P.
2006-09-01
Accurate lip-reading techniques would be of enormous benefit for agencies involved in counter-terrorism and other law-enforcement areas. Unfortunately, there are very few skilled lip-readers, and it is apparently a difficult skill to transmit, so the area is under-resourced. In this paper we investigate the possibility of making the lip-reading task more amenable to a wider range of operators by enhancing lip movements in video sequences using active appearance models. These are generative, parametric models commonly used to track faces in images and video sequences. The parametric nature of the model allows a face in an image to be encoded in terms of a few tens of parameters, while the generative nature allows faces to be re-synthesised using the parameters. The aim of this study is to determine if exaggerating lip-motions in video sequences by amplifying the parameters of the model improves lip-reading ability. We also present results of lip-reading tests undertaken by experienced (but non-expert) adult subjects who claim to use lip-reading in their speech recognition process. The results, which are comparisons of word error-rates on unprocessed and processed video, are mixed. We find that there appears to be the potential to improve the word error rate but, for the method to improve the intelligibility there is need for more sophisticated tracking and visual modelling. Our technique can also act as an expression or visual gesture amplifier and so has applications to animation and the presentation of information via avatars or synthetic humans.
NASA Astrophysics Data System (ADS)
Wang, Guanxi; Tie, Yun; Qi, Lin
2017-07-01
In this paper, we propose a novel approach based on Depth Maps and compute Multi-Scale Histograms of Oriented Gradient (MSHOG) from sequences of depth maps to recognize actions. Each depth frame in a depth video sequence is projected onto three orthogonal Cartesian planes. Under each projection view, the absolute difference between two consecutive projected maps is accumulated through a depth video sequence to form a Depth Map, which is called Depth Motion Trail Images (DMTI). The MSHOG is then computed from the Depth Maps for the representation of an action. In addition, we apply L2-Regularized Collaborative Representation (L2-CRC) to classify actions. We evaluate the proposed approach on MSR Action3D dataset and MSRGesture3D dataset. Promising experimental result demonstrates the effectiveness of our proposed method.
The Culturally Competent Art Educator.
ERIC Educational Resources Information Center
Andrus, Lucy
2001-01-01
Focuses on the importance of preparing teachers to be culturally competent art educators, addresses the qualities of a culturally competent teacher, delineates Mazrui's seven functions of culture, and explores how to comprehend multicultural practice. Discusses how teachers can acquire cultural knowledge through literature, films and videos, and…
Pediatric head and neck lesions: assessment of vascularity by MR digital subtraction angiography.
Chooi, Weng Kong; Woodhouse, Neil; Coley, Stuart C; Griffiths, Paul D
2004-08-01
Pediatric head and neck lesions can be difficult to characterize on clinical grounds alone. We investigated the use of dynamic MR digital subtraction angiography as a noninvasive adjunct for the assessment of the vascularity of these abnormalities. Twelve patients (age range, 2 days to 16 years) with known or suspected vascular abnormalities were studied. Routine MR imaging, time-of-flight MR angiography, and MR digital subtraction angiography were performed in all patients. The dynamic sequence was acquired in two planes at one frame per second by using a thick section (6-10 cm) selective radio-frequency spoiled fast gradient-echo sequence and an IV administered bolus of contrast material. The images were subtracted from a preliminary mask sequence and viewed as a video-inverted cine loop. In all cases, MR digital subtraction angiography was successfully performed. The technique showed the following: 1) slow flow lesions (two choroidal angiomas, eyelid hemangioma, and scalp venous malformation); 2) high flow lesions that were not always suspected by clinical examination alone (parotid hemangioma, scalp, occipital, and eyelid arteriovenous malformations plus a palatal teratoma); 3) a hypovascular tumor for which a biopsy could be safely performed (Burkitt lymphoma); and 4) a hypervascular tumor of the palate (cystic teratoma). Our early experience suggests that MR digital subtraction angiography can be reliably performed in children of all ages without complication. The technique provided a noninvasive assessment of the vascularity of each lesion that could not always have been predicted on the basis of clinical examination or routine MR imaging alone.
Gandini, C. L.; Sanchez-Puerta, M. V.
2017-01-01
Angiosperm mitochondrial genomes (mtDNA) exhibit variable quantities of alien sequences. Many of these sequences are acquired by intracellular gene transfer (IGT) from the plastid. In addition, frequent events of horizontal gene transfer (HGT) between mitochondria of different species also contribute to their expanded genomes. In contrast, alien sequences are rarely found in plastid genomes. Most of the plant-to-plant HGT events involve mitochondrion-to-mitochondrion transfers. Occasionally, foreign sequences in mtDNAs are plastid-derived (MTPT), raising questions about their origin, frequency, and mechanism of transfer. The rising number of complete mtDNAs allowed us to address these questions. We identified 15 new foreign MTPTs, increasing significantly the number of those previously reported. One out of five of the angiosperm species analyzed contained at least one foreign MTPT, suggesting a remarkable frequency of HGT among plants. By analyzing the flanking regions of the foreign MTPTs, we found strong evidence for mt-to-mt transfers in 65% of the cases. We hypothesize that plastid sequences were initially acquired by the native mtDNA via IGT and then transferred to a distantly-related plant via mitochondrial HGT, rather than directly from a foreign plastid to the mitochondrial genome. Finally, we describe three novel putative cases of mitochondrial-derived sequences among angiosperm plastomes. PMID:28262720
CVD2014-A Database for Evaluating No-Reference Video Quality Assessment Algorithms.
Nuutinen, Mikko; Virtanen, Toni; Vaahteranoksa, Mikko; Vuori, Tero; Oittinen, Pirkko; Hakkinen, Jukka
2016-07-01
In this paper, we present a new video database: CVD2014-Camera Video Database. In contrast to previous video databases, this database uses real cameras rather than introducing distortions via post-processing, which results in a complex distortion space in regard to the video acquisition process. CVD2014 contains a total of 234 videos that are recorded using 78 different cameras. Moreover, this database contains the observer-specific quality evaluation scores rather than only providing mean opinion scores. We have also collected open-ended quality descriptions that are provided by the observers. These descriptions were used to define the quality dimensions for the videos in CVD2014. The dimensions included sharpness, graininess, color balance, darkness, and jerkiness. At the end of this paper, a performance study of image and video quality algorithms for predicting the subjective video quality is reported. For this performance study, we proposed a new performance measure that accounts for observer variance. The performance study revealed that there is room for improvement regarding the video quality assessment algorithms. The CVD2014 video database has been made publicly available for the research community. All video sequences and corresponding subjective ratings can be obtained from the CVD2014 project page (http://www.helsinki.fi/psychology/groups/visualcognition/).
Auto-tracking system for human lumbar motion analysis.
Sui, Fuge; Zhang, Da; Lam, Shing Chun Benny; Zhao, Lifeng; Wang, Dongjun; Bi, Zhenggang; Hu, Yong
2011-01-01
Previous lumbar motion analyses suggest the usefulness of quantitatively characterizing spine motion. However, the application of such measurements is still limited by the lack of user-friendly automatic spine motion analysis systems. This paper describes an automatic analysis system to measure lumbar spine disorders that consists of a spine motion guidance device, an X-ray imaging modality to acquire digitized video fluoroscopy (DVF) sequences and an automated tracking module with a graphical user interface (GUI). DVF sequences of the lumbar spine are recorded during flexion-extension under a guidance device. The automatic tracking software utilizing a particle filter locates the vertebra-of-interest in every frame of the sequence, and the tracking result is displayed on the GUI. Kinematic parameters are also extracted from the tracking results for motion analysis. We observed that, in a bone model test, the maximum fiducial error was 3.7%, and the maximum repeatability error in translation and rotation was 1.2% and 2.6%, respectively. In our simulated DVF sequence study, the automatic tracking was not successful when the noise intensity was greater than 0.50. In a noisy situation, the maximal difference was 1.3 mm in translation and 1° in the rotation angle. The errors were calculated in translation (fiducial error: 2.4%, repeatability error: 0.5%) and in the rotation angle (fiducial error: 1.0%, repeatability error: 0.7%). However, the automatic tracking software could successfully track simulated sequences contaminated by noise at a density ≤ 0.5 with very high accuracy, providing good reliability and robustness. A clinical trial with 10 healthy subjects and 2 lumbar spondylolisthesis patients were enrolled in this study. The measurement with auto-tacking of DVF provided some information not seen in the conventional X-ray. The results proposed the potential use of the proposed system for clinical applications.
Molinari, Luisa; Mameli, Consuelo; Gnisci, Augusto
2013-09-01
A sequential analysis of classroom discourse is needed to investigate the conditions under which the triadic initiation-response-feedback (IRF) pattern may host different teaching orientations. The purpose of the study is twofold: first, to describe the characteristics of classroom discourse and, second, to identify and explore the different interactive sequences that can be captured with a sequential statistical analysis. Twelve whole-class activities were video recorded in three Italian primary schools. We observed classroom interaction as it occurs naturally on an everyday basis. In total, we collected 587 min of video recordings. Subsequently, 828 triadic IRF patterns were extracted from this material and analysed with the programme Generalized Sequential Query (GSEQ). The results indicate that classroom discourse may unfold in different ways. In particular, we identified and described four types of sequences. Dialogic sequences were triggered by authentic questions, and continued through further relaunches. Monologic sequences were directed to fulfil the teachers' pre-determined didactic purposes. Co-constructive sequences fostered deduction, reasoning, and thinking. Scaffolding sequences helped and sustained children with difficulties. The application of sequential analyses allowed us to show that interactive sequences may account for a variety of meanings, thus making a significant contribution to the literature and research practice in classroom discourse. © 2012 The British Psychological Society.
Fries, Peter; Runge, Val M; Kirchin, Miles A; Stemmer, Alto; Naul, L Gill; Wiliams, Kenneth D; Reith, Wolfgang; Bücker, Arno; Schneider, Günther
2009-06-01
To compare diffusion-weighted imaging (DWI) based on a fast spin echo (FSE) sequence using BLADE (PROPELLER) with conventional DWI-echoplanar imaging (EPI) techniques at 3 T and to demonstrate the influence of hardware developments on signal-to-noise ratio (SNR) with these techniques using 12- and 32-channel head coils. Fourteen patients with brain ischemia were evaluated with DWI using EPI and FSE BLADE sequences, with a 12-channel head coil, in the axial plane and 1 additional plane (either sagittal or coronal). SNR and CNR were calculated from region-of-interest measurements. Scans were evaluated in a blinded fashion by 2 experienced neuroradiologists. SNR of both DWI techniques was evaluated in 12 healthy volunteers using different parallel imaging (PI) factors (for the EPI sequence) and both the 12- and 32-channel coils. DWI-BLADE sequences acquired with the 12-channel coil revealed a significant reduction in SNR (mean +/- SD) of ischemic lesions (SNR(lesion) [5.0 +/- 2.5]), normal brain (SNR(brain) [3.0 +/- 1.9]), and subsequently in CNR (3.0 +/- 1.8) as compared with the DWI-EPI sequence (SNR(lesion) [9.3 +/- 5.2], SNR(brain) [7.7 +/- 3.5], CNR [6.1 +/- 2.8], P < 0.001). Despite this reduction in SNR and CNR, the blinded read revealed a marked preference for the DWI-BLADE sequence, or equality between the sequences, in the majority of patients because lesion detection was degraded by susceptibility artifacts on axial DWI-EPI scans in 14% to 43% of cases (but in no instance with the DWI-BLADE sequence). In particular, preference for the DWI-BLADE sequence or equality between the 2 techniques for lesion detection in the brainstem and cerebellum was observed. On some DWI-BLADE scans, in the additional plane, radial-like artifacts degraded lesion detection.In volunteers, SNR was significantly improved using the 32-channel coil, irrespective of scan technique. Comparing DWI-EPI acquired with the 12-channel coil (iPAT = 2) to DWI-BLADE acquired with the 32-channel coil, comparable SNR values were obtained. The 32-channel coil also makes feasible, with DWI-EPI, an increase in the PI factor to 4, which allows for a further reduction of bulk susceptibility artifacts. However, still DWI-BLADE sequences performed better because of absence of bulk susceptibility artifacts at comparable SNR values. Despite lower SNR at comparable PI factors, DWI-BLADE sequences acquired using the 12-channel coil are preferable in most instances, as compared with DWI-EPI sequences, because of the absence of susceptibility artifacts and subsequently improved depiction of ischemic lesions in the brainstem and cerebellum. With the 32-channel coil, recently FDA approved, DWI-BLADE acquired with an iPAT = 2 provides comparable SNR without bulk susceptibility artifacts as compared with the DWI-EPI sequences acquired for clinical routine to date and has the potential to replace the standard DWI technique for special indications like DWI of the cerebellum and the brainstem or in presence of metallic implants or hemorrhage.
Scrambling for anonymous visual communications
NASA Astrophysics Data System (ADS)
Dufaux, Frederic; Ebrahimi, Touradj
2005-08-01
In this paper, we present a system for anonymous visual communications. Target application is an anonymous video chat. The system is identifying faces in the video sequence by means of face detection or skin detection. The corresponding regions are subsequently scrambled. We investigate several approaches for scrambling, either in the image-domain or in the transform-domain. Experiment results show the effectiveness of the proposed system.
Fingerprint multicast in secure video streaming.
Zhao, H Vicky; Liu, K J Ray
2006-01-01
Digital fingerprinting is an emerging technology to protect multimedia content from illegal redistribution, where each distributed copy is labeled with unique identification information. In video streaming, huge amount of data have to be transmitted to a large number of users under stringent latency constraints, so the bandwidth-efficient distribution of uniquely fingerprinted copies is crucial. This paper investigates the secure multicast of anticollusion fingerprinted video in streaming applications and analyzes their performance. We first propose a general fingerprint multicast scheme that can be used with most spread spectrum embedding-based multimedia fingerprinting systems. To further improve the bandwidth efficiency, we explore the special structure of the fingerprint design and propose a joint fingerprint design and distribution scheme. From our simulations, the two proposed schemes can reduce the bandwidth requirement by 48% to 87%, depending on the number of users, the characteristics of video sequences, and the network and computation constraints. We also show that under the constraint that all colluders have the same probability of detection, the embedded fingerprints in the two schemes have approximately the same collusion resistance. Finally, we propose a fingerprint drift compensation scheme to improve the quality of the reconstructed sequences at the decoder's side without introducing extra communication overhead.
Motion adaptive Kalman filter for super-resolution
NASA Astrophysics Data System (ADS)
Richter, Martin; Nasse, Fabian; Schröder, Hartmut
2011-01-01
Superresolution is a sophisticated strategy to enhance image quality of both low and high resolution video, performing tasks like artifact reduction, scaling and sharpness enhancement in one algorithm, all of them reconstructing high frequency components (above Nyquist frequency) in some way. Especially recursive superresolution algorithms can fulfill high quality aspects because they control the video output using a feed-back loop and adapt the result in the next iteration. In addition to excellent output quality, temporal recursive methods are very hardware efficient and therefore even attractive for real-time video processing. A very promising approach is the utilization of Kalman filters as proposed by Farsiu et al. Reliable motion estimation is crucial for the performance of superresolution. Therefore, robust global motion models are mainly used, but this also limits the application of superresolution algorithm. Thus, handling sequences with complex object motion is essential for a wider field of application. Hence, this paper proposes improvements by extending the Kalman filter approach using motion adaptive variance estimation and segmentation techniques. Experiments confirm the potential of our proposal for ideal and real video sequences with complex motion and further compare its performance to state-of-the-art methods like trainable filters.
Construction of a multimodal CT-video chest model
NASA Astrophysics Data System (ADS)
Byrnes, Patrick D.; Higgins, William E.
2014-03-01
Bronchoscopy enables a number of minimally invasive chest procedures for diseases such as lung cancer and asthma. For example, using the bronchoscope's continuous video stream as a guide, a physician can navigate through the lung airways to examine general airway health, collect tissue samples, or administer a disease treatment. In addition, physicians can now use new image-guided intervention (IGI) systems, which draw upon both three-dimensional (3D) multi-detector computed tomography (MDCT) chest scans and bronchoscopic video, to assist with bronchoscope navigation. Unfortunately, little use is made of the acquired video stream, a potentially invaluable source of information. In addition, little effort has been made to link the bronchoscopic video stream to the detailed anatomical information given by a patient's 3D MDCT chest scan. We propose a method for constructing a multimodal CT-video model of the chest. After automatically computing a patient's 3D MDCT-based airway-tree model, the method next parses the available video data to generate a positional linkage between a sparse set of key video frames and airway path locations. Next, a fusion/mapping of the video's color mucosal information and MDCT-based endoluminal surfaces is performed. This results in the final multimodal CT-video chest model. The data structure constituting the model provides a history of those airway locations visited during bronchoscopy. It also provides for quick visual access to relevant sections of the airway wall by condensing large portions of endoscopic video into representative frames containing important structural and textural information. When examined with a set of interactive visualization tools, the resulting fused data structure provides a rich multimodal data source. We demonstrate the potential of the multimodal model with both phantom and human data.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-25
...) requires limited partners, Registered Limited Liability Partnerships (``RLLPs''), and Limited Liability... limited partnership interest. 47 CFR 76.503(g) states ``Prior to acquiring additional multichannel video... for limited partners who are not materially involved, directly or indirectly, in the management or...
Teaching Helping to Adolescents with Autism
ERIC Educational Resources Information Center
Day-Watkins, Jessica; Murray, Rachel; Connell, James E.
2014-01-01
This study is a replication and extension of Reeve, Reeve, Townsend, and Poulson (2007) evaluating the effects of a treatment package that included multiple-exemplar training, video modeling, prompting, and reinforcement on helping of 3 adolescents with autism. Results demonstrated that all participants acquired the helping responses. Probes…
SAFE: Stopping AIDS through Functional Education.
ERIC Educational Resources Information Center
Hylton, Judith
This functional curriculum is intended to teach people with developmental disabilities or other learning problems how to prevent infection with HIV/AIDS (Human Immunodeficiency Virus/Acquired Immune Deficiency Syndrome). The entire curriculum includes six video segments, four illustrated brochures, 28 slides and illustrations, as well as a guide…
Automated multiple target detection and tracking in UAV videos
NASA Astrophysics Data System (ADS)
Mao, Hongwei; Yang, Chenhui; Abousleman, Glen P.; Si, Jennie
2010-04-01
In this paper, a novel system is presented to detect and track multiple targets in Unmanned Air Vehicles (UAV) video sequences. Since the output of the system is based on target motion, we first segment foreground moving areas from the background in each video frame using background subtraction. To stabilize the video, a multi-point-descriptor-based image registration method is performed where a projective model is employed to describe the global transformation between frames. For each detected foreground blob, an object model is used to describe its appearance and motion information. Rather than immediately classifying the detected objects as targets, we track them for a certain period of time and only those with qualified motion patterns are labeled as targets. In the subsequent tracking process, a Kalman filter is assigned to each tracked target to dynamically estimate its position in each frame. Blobs detected at a later time are used as observations to update the state of the tracked targets to which they are associated. The proposed overlap-rate-based data association method considers the splitting and merging of the observations, and therefore is able to maintain tracks more consistently. Experimental results demonstrate that the system performs well on real-world UAV video sequences. Moreover, careful consideration given to each component in the system has made the proposed system feasible for real-time applications.
Vladescu, Jason C; Carroll, Regina; Paden, Amber; Kodak, Tiffany M
2012-01-01
The present study replicates and extends previous research on the use of video modeling (VM) with voiceover instruction to train staff to implement discrete-trial instruction (DTI). After staff trainees reached the mastery criterion when teaching an adult confederate with VM, they taught a child with a developmental disability using DTI. The results showed that the staff trainees' accurate implementation of DTI remained high, and both child participants acquired new skills. These findings provide additional support that VM may be an effective method to train staff members to conduct DTI. PMID:22844149
Vladescu, Jason C; Carroll, Regina; Paden, Amber; Kodak, Tiffany M
2012-01-01
The present study replicates and extends previous research on the use of video modeling (VM) with voiceover instruction to train staff to implement discrete-trial instruction (DTI). After staff trainees reached the mastery criterion when teaching an adult confederate with VM, they taught a child with a developmental disability using DTI. The results showed that the staff trainees' accurate implementation of DTI remained high, and both child participants acquired new skills. These findings provide additional support that VM may be an effective method to train staff members to conduct DTI.
Unattended real-time re-establishment of visibility in high dynamic range video and stills
NASA Astrophysics Data System (ADS)
Abidi, B.
2014-05-01
We describe a portable unattended persistent surveillance system that corrects for harsh illumination conditions, where bright sun light creates mixed contrast effects, i.e., heavy shadows and washouts. These effects result in high dynamic range scenes, where illuminance can vary from few luxes to a 6 figure value. When using regular monitors and cameras, such wide span of illuminations can only be visualized if the actual range of values is compressed, leading to the creation of saturated and/or dark noisy areas and a loss of information in these areas. Images containing extreme mixed contrast cannot be fully enhanced from a single exposure, simply because all information is not present in the original data. The active intervention in the acquisition process is required. A software package, capable of integrating multiple types of COTS and custom cameras, ranging from Unmanned Aerial Systems (UAS) data links to digital single-lens reflex cameras (DSLR), is described. Hardware and software are integrated via a novel smart data acquisition algorithm, which communicates to the camera the parameters that would maximize information content in the final processed scene. A fusion mechanism is then applied to the smartly acquired data, resulting in an enhanced scene where information in both dark and bright areas is revealed. Multi-threading and parallel processing are exploited to produce automatic real time full motion corrected video. A novel enhancement algorithm was also devised to process data from legacy and non-controllable cameras. The software accepts and processes pre-recorded sequences and stills, enhances visible, night vision, and Infrared data, and successfully applies to night time and dark scenes. Various user options are available, integrating custom functionalities of the application into intuitive and easy to use graphical interfaces. The ensuing increase in visibility in surveillance video and intelligence imagery will expand the performance and timely decision making of the human analyst, as well as that of unmanned systems performing automatic data exploitation, such as target detection and identification.
Prinz, A; Bolz, M; Findl, O
2005-01-01
Background/aim: Owing to the complex topographical aspects of ophthalmic surgery, teaching with conventional surgical videos has led to a poor understanding among medical students. A novel multimedia three dimensional (3D) computer animated program, called “Ophthalmic Operation Vienna” has been developed, where surgical videos are accompanied by 3D animated sequences of all surgical steps for five operations. The aim of the study was to assess the effect of 3D animations on the understanding of cataract and glaucoma surgery among medical students. Method: Set in the Medical University of Vienna, Department of Ophthalmology, 172 students were randomised into two groups: a 3D group (n = 90), that saw the 3D animations and video sequences, and a control group (n = 82), that saw only the surgical videos. The narrated text was identical for both groups. After the presentation, students were questioned and tested using multiple choice questions. Results: Students in the 3D group found the interactive multimedia teaching methods to be a valuable supplement to the conventional surgical videos. The 3D group outperformed the control group not only in topographical understanding by 16% (p<0.0001), but also in theoretical understanding by 7% (p<0.003). Women in the 3D group gained most by 19% over the control group (p<0.0001). Conclusions: The use of 3D animations lead to a better understanding of difficult surgical topics among medical students, especially for female users. Gender related benefits of using multimedia should be further explored. PMID:16234460
Besera, Ghenet T; Cox, Shanna; Malotte, C Kevin; Rietmeijer, Cornelis A; Klausner, Jeffrey D; O'Donnell, Lydia; Margolis, Andrew D; Warner, Lee
2016-09-01
Safe in the City, a video intervention for clinic waiting rooms, was previously shown to reduce sexually transmitted disease (STD) incidence. However, little is known about patients' recall of exposure to the intervention. Using data from a nested study of patients attending clinics during the trial, we assessed whether participants recalled Safe in the City, and, if so, how the intervention affected subsequent attitudes and behaviors. Analyses were restricted to responses to a 3-month follow-up questionnaire among participants who were exposed to the video (n = 708). Impact was measured as participants' reports of the video's effect on behaviors and attitudes. Associations were evaluated using multivariable logistic regression. Of participants who were exposed, 685 (97%) recalled viewing the video, and 68% recalled all three vignettes. After watching the video, participants felt more positive about condoms (69%) and comfortable acquiring condoms (56%), were reminded of important information about STDs and condoms (90%), and tried to apply what they learned to their lives (59%). Compared with those who recalled viewing one or two vignettes, participants who recalled viewing all three vignettes reported more positive attitudes toward condoms and peer/provider communication. These findings demonstrate that a low-resource video intervention for waiting rooms can provide sufficient exposure to positively influence STD-related attitudes/behaviors. © 2016 Society for Public Health Education.
Real-time filtering and detection of dynamics for compression of HDTV
NASA Technical Reports Server (NTRS)
Sauer, Ken D.; Bauer, Peter
1991-01-01
The preprocessing of video sequences for data compressing is discussed. The end goal associated with this is a compression system for HDTV capable of transmitting perceptually lossless sequences at under one bit per pixel. Two subtopics were emphasized to prepare the video signal for more efficient coding: (1) nonlinear filtering to remove noise and shape the signal spectrum to take advantage of insensitivities of human viewers; and (2) segmentation of each frame into temporally dynamic/static regions for conditional frame replenishment. The latter technique operates best under the assumption that the sequence can be modelled as a superposition of active foreground and static background. The considerations were restricted to monochrome data, since it was expected to use the standard luminance/chrominance decomposition, which concentrates most of the bandwidth requirements in the luminance. Similar methods may be applied to the two chrominance signals.
Dynamic video encryption algorithm for H.264/AVC based on a spatiotemporal chaos system.
Xu, Hui; Tong, Xiao-Jun; Zhang, Miao; Wang, Zhu; Li, Ling-Hao
2016-06-01
Video encryption schemes mostly employ the selective encryption method to encrypt parts of important and sensitive video information, aiming to ensure the real-time performance and encryption efficiency. The classic block cipher is not applicable to video encryption due to the high computational overhead. In this paper, we propose the encryption selection control module to encrypt video syntax elements dynamically which is controlled by the chaotic pseudorandom sequence. A novel spatiotemporal chaos system and binarization method is used to generate a key stream for encrypting the chosen syntax elements. The proposed scheme enhances the resistance against attacks through the dynamic encryption process and high-security stream cipher. Experimental results show that the proposed method exhibits high security and high efficiency with little effect on the compression ratio and time cost.
Automated Production of Movies on a Cluster of Computers
NASA Technical Reports Server (NTRS)
Nail, Jasper; Le, Duong; Nail, William L.; Nail, William
2008-01-01
A method of accelerating and facilitating production of video and film motion-picture products, and software and generic designs of computer hardware to implement the method, are undergoing development. The method provides for automation of most of the tedious and repetitive tasks involved in editing and otherwise processing raw digitized imagery into final motion-picture products. The method was conceived to satisfy requirements, in industrial and scientific testing, for rapid processing of multiple streams of simultaneously captured raw video imagery into documentation in the form of edited video imagery and video derived data products for technical review and analysis. In the production of such video technical documentation, unlike in production of motion-picture products for entertainment, (1) it is often necessary to produce multiple video derived data products, (2) there are usually no second chances to repeat acquisition of raw imagery, (3) it is often desired to produce final products within minutes rather than hours, days, or months, and (4) consistency and quality, rather than aesthetics, are the primary criteria for judging the products. In the present method, the workflow has both serial and parallel aspects: processing can begin before all the raw imagery has been acquired, each video stream can be subjected to different stages of processing simultaneously on different computers that may be grouped into one or more cluster(s), and the final product may consist of multiple video streams. Results of processing on different computers are shared, so that workers can collaborate effectively.
The Concrete-Representational-Abstract Sequence of Instruction in Mathematics Classrooms
ERIC Educational Resources Information Center
Mudaly, Vimolan; Naidoo, Jayaluxmi
2015-01-01
The purpose of this paper is to explore how master mathematics teachers use the concrete-representational-abstract (CRA) sequence of instruction in mathematics classrooms. Data was collected from a convenience sample of six master teachers by observations, video recordings of their teaching, and semi-structured interviews. Data collection also…
Teacher Deployment of "Oh" in Known-Answer Question Sequences
ERIC Educational Resources Information Center
Hosoda, Yuri
2016-01-01
This conversation analytic study describes some specific interactional contexts in which native English-speaking teachers produce "oh" in known-answer question sequences in English language classes. The data for this study come from 10 video-recorded Japanese primary school English language class sessions. The analysis identified three…
Underwater video enhancement using multi-camera super-resolution
NASA Astrophysics Data System (ADS)
Quevedo, E.; Delory, E.; Callicó, G. M.; Tobajas, F.; Sarmiento, R.
2017-12-01
Image spatial resolution is critical in several fields such as medicine, communications or satellite, and underwater applications. While a large variety of techniques for image restoration and enhancement has been proposed in the literature, this paper focuses on a novel Super-Resolution fusion algorithm based on a Multi-Camera environment that permits to enhance the quality of underwater video sequences without significantly increasing computation. In order to compare the quality enhancement, two objective quality metrics have been used: PSNR (Peak Signal-to-Noise Ratio) and the SSIM (Structural SIMilarity) index. Results have shown that the proposed method enhances the objective quality of several underwater sequences, avoiding the appearance of undesirable artifacts, with respect to basic fusion Super-Resolution algorithms.
Phase-based motion magnification video for monitoring of vital signals using the Hermite transform
NASA Astrophysics Data System (ADS)
Brieva, Jorge; Moya-Albor, Ernesto
2017-11-01
In this paper we present a new Eulerian phase-based motion magnification technique using the Hermite Transform (HT) decomposition that is inspired in the Human Vision System (HVS). We test our method in one sequence of the breathing of a newborn baby and on a video sequence that shows the heartbeat on the wrist. We detect and magnify the heart pulse applying our technique. Our motion magnification approach is compared to the Laplacian phase based approach by means of quantitative metrics (based on the RMS error and the Fourier transform) to measure the quality of both reconstruction and magnification. In addition a noise robustness analysis is performed for the two methods.
Connors, Erin C; Chrastil, Elizabeth R; Sánchez, Jaime; Merabet, Lotfi B
2014-01-01
For individuals who are blind, navigating independently in an unfamiliar environment represents a considerable challenge. Inspired by the rising popularity of video games, we have developed a novel approach to train navigation and spatial cognition skills in adolescents who are blind. Audio-based Environment Simulator (AbES) is a software application that allows for the virtual exploration of an existing building set in an action video game metaphor. Using this ludic-based approach to learning, we investigated the ability and efficacy of adolescents with early onset blindness to acquire spatial information gained from the exploration of a target virtual indoor environment. Following game play, participants were assessed on their ability to transfer and mentally manipulate acquired spatial information on a set of navigation tasks carried out in the real environment. Success in transfer of navigation skill performance was markedly high suggesting that interacting with AbES leads to the generation of an accurate spatial mental representation. Furthermore, there was a positive correlation between success in game play and navigation task performance. The role of virtual environments and gaming in the development of mental spatial representations is also discussed. We conclude that this game based learning approach can facilitate the transfer of spatial knowledge and further, can be used by individuals who are blind for the purposes of navigation in real-world environments.
Connors, Erin C.; Chrastil, Elizabeth R.; Sánchez, Jaime; Merabet, Lotfi B.
2014-01-01
For individuals who are blind, navigating independently in an unfamiliar environment represents a considerable challenge. Inspired by the rising popularity of video games, we have developed a novel approach to train navigation and spatial cognition skills in adolescents who are blind. Audio-based Environment Simulator (AbES) is a software application that allows for the virtual exploration of an existing building set in an action video game metaphor. Using this ludic-based approach to learning, we investigated the ability and efficacy of adolescents with early onset blindness to acquire spatial information gained from the exploration of a target virtual indoor environment. Following game play, participants were assessed on their ability to transfer and mentally manipulate acquired spatial information on a set of navigation tasks carried out in the real environment. Success in transfer of navigation skill performance was markedly high suggesting that interacting with AbES leads to the generation of an accurate spatial mental representation. Furthermore, there was a positive correlation between success in game play and navigation task performance. The role of virtual environments and gaming in the development of mental spatial representations is also discussed. We conclude that this game based learning approach can facilitate the transfer of spatial knowledge and further, can be used by individuals who are blind for the purposes of navigation in real-world environments. PMID:24653690
Classroom Social Signal Analysis
ERIC Educational Resources Information Center
Raca, Mirko; Dillenbourg, Pierre
2014-01-01
We present our efforts towards building an observational system for measuring classroom activity. The goal is to explore visual cues which can be acquired with a system of video cameras and automatically processed to enrich the teacher's perception of the audience. The paper will give a brief overview of our methodology, explored features, and…
NASA Astrophysics Data System (ADS)
Zhang, Hanqing; Stangner, Tim; Wiklund, Krister; Rodriguez, Alvaro; Andersson, Magnus
2017-10-01
We present a versatile and fast MATLAB program (UmUTracker) that automatically detects and tracks particles by analyzing video sequences acquired by either light microscopy or digital in-line holographic microscopy. Our program detects the 2D lateral positions of particles with an algorithm based on the isosceles triangle transform, and reconstructs their 3D axial positions by a fast implementation of the Rayleigh-Sommerfeld model using a radial intensity profile. To validate the accuracy and performance of our program, we first track the 2D position of polystyrene particles using bright field and digital holographic microscopy. Second, we determine the 3D particle position by analyzing synthetic and experimentally acquired holograms. Finally, to highlight the full program features, we profile the microfluidic flow in a 100 μm high flow chamber. This result agrees with computational fluid dynamic simulations. On a regular desktop computer UmUTracker can detect, analyze, and track multiple particles at 5 frames per second for a template size of 201 ×201 in a 1024 × 1024 image. To enhance usability and to make it easy to implement new functions we used object-oriented programming. UmUTracker is suitable for studies related to: particle dynamics, cell localization, colloids and microfluidic flow measurement. Program Files doi : http://dx.doi.org/10.17632/fkprs4s6xp.1 Licensing provisions : Creative Commons by 4.0 (CC by 4.0) Programming language : MATLAB Nature of problem: 3D multi-particle tracking is a common technique in physics, chemistry and biology. However, in terms of accuracy, reliable particle tracking is a challenging task since results depend on sample illumination, particle overlap, motion blur and noise from recording sensors. Additionally, the computational performance is also an issue if, for example, a computationally expensive process is executed, such as axial particle position reconstruction from digital holographic microscopy data. Versatile robust tracking programs handling these concerns and providing a powerful post-processing option are significantly limited. Solution method: UmUTracker is a multi-functional tool to extract particle positions from long video sequences acquired with either light microscopy or digital holographic microscopy. The program provides an easy-to-use graphical user interface (GUI) for both tracking and post-processing that does not require any programming skills to analyze data from particle tracking experiments. UmUTracker first conduct automatic 2D particle detection even under noisy conditions using a novel circle detector based on the isosceles triangle sampling technique with a multi-scale strategy. To reduce the computational load for 3D tracking, it uses an efficient implementation of the Rayleigh-Sommerfeld light propagation model. To analyze and visualize the data, an efficient data analysis step, which can for example show 4D flow visualization using 3D trajectories, is included. Additionally, UmUTracker is easy to modify with user-customized modules due to the object-oriented programming style Additional comments: Program obtainable from https://sourceforge.net/projects/umutracker/
NASA Astrophysics Data System (ADS)
Mantel, Claire; Korhonen, Jari; Pedersen, Jesper M.; Bech, Søren; Andersen, Jakob Dahl; Forchhammer, Søren
2015-01-01
This paper focuses on the influence of ambient light on the perceived quality of videos displayed on Liquid Crystal Display (LCD) with local backlight dimming. A subjective test assessing the quality of videos with two backlight dimming methods and three lighting conditions, i.e. no light, low light level (5 lux) and higher light level (60 lux) was organized to collect subjective data. Results show that participants prefer the method exploiting local dimming possibilities to the conventional full backlight but that this preference varies depending on the ambient light level. The clear preference for one method at the low light conditions decreases at the high ambient light, confirming that the ambient light significantly attenuates the perception of the leakage defect (light leaking through dark pixels). Results are also highly dependent on the content of the sequence, which can modulate the effect of the ambient light from having an important influence on the quality grades to no influence at all.
Fernández-Aranda, Fernando; Jiménez-Murcia, Susana; Santamaría, Juan J.; Gunnard, Katarina; Soto, Antonio; Kalapanidas, Elias; Bults, Richard G. A.; Davarakis, Costas; Ganchev, Todor; Granero, Roser; Konstantas, Dimitri; Kostoulas, Theodoros P.; Lam, Tony; Lucas, Mikkel; Masuet-Aumatell, Cristina; Moussa, Maher H.; Nielsen, Jeppe; Penelo, Eva
2012-01-01
Background: Previous review studies have suggested that computer games can serve as an alternative or additional form of treatment in several areas (schizophrenia, asthma or motor rehabilitation). Although several naturalistic studies have been conducted showing the usefulness of serious video games in the treatment of some abnormal behaviours, there is a lack of serious games specially designed for treating mental disorders. Aim: The purpose of our project was to develop and evaluate a serious video game designed to remediate attitudinal, behavioural and emotional processes of patients with impulse-related disorders. Method and results: The video game was created and developed within the European research project PlayMancer. It aims to prove potential capacity to change underlying attitudinal, behavioural and emotional processes of patients with impulse-related disorders. New interaction modes were provided by newly developed components, such as emotion recognition from speech, face and physiological reactions, while specific impulsive reactions were elicited. The video game uses biofeedback for helping patients to learn relaxation skills, acquire better self-control strategies and develop new emotional regulation strategies. In this article, we present a description of the video game used, rationale, user requirements, usability and preliminary data, in several mental disorders. PMID:22548300
Costa, Tarcila Lima da; Souza, Olivia Mesquita Vieira de; Carneiro, Homero Aferri; Chiquito Netto, Cristianne; Pegoraro-Krook, Maria Inês; Dutka, Jeniffer de Cássia Rillo
2016-01-01
The objective of this study was to describe the process of elaboration and evaluation of multimedia material for caregivers about velopharynx, speech, and primary palatoplasty in babies with cleft lip and palate. The elaboration of the material involved an interdisciplinary relationship between the fields of Speech Language Pathology and Audiology, Dentistry and Arts. The definition and execution of the following activities were based on the principles of art education involving the following: characterization of audience, characterization of content, identification and elaboration of illustrations, characterization of educational approach, elaboration of text and narratives, definition of audiovisual sequence, and video preparation. The material was evaluated with the participation of 41 caregivers of patients with cleft lip and palate involving the comparison between acquired knowledge using an evaluation script applied before and after presenting the material. An increase was observed in correct responses regarding the role of velopharynx and the importance of primary palatoplasty for speech. The multimedia was effective in optimizing the knowledge of caregivers, suggesting the importance of such material during orientation.
Zhao, Zijian; Voros, Sandrine; Weng, Ying; Chang, Faliang; Li, Ruijian
2017-12-01
Worldwide propagation of minimally invasive surgeries (MIS) is hindered by their drawback of indirect observation and manipulation, while monitoring of surgical instruments moving in the operated body required by surgeons is a challenging problem. Tracking of surgical instruments by vision-based methods is quite lucrative, due to its flexible implementation via software-based control with no need to modify instruments or surgical workflow. A MIS instrument is conventionally split into a shaft and end-effector portions, while a 2D/3D tracking-by-detection framework is proposed, which performs the shaft tracking followed by the end-effector one. The former portion is described by line features via the RANSAC scheme, while the latter is depicted by special image features based on deep learning through a well-trained convolutional neural network. The method verification in 2D and 3D formulation is performed through the experiments on ex-vivo video sequences, while qualitative validation on in-vivo video sequences is obtained. The proposed method provides robust and accurate tracking, which is confirmed by the experimental results: its 3D performance in ex-vivo video sequences exceeds those of the available state-of -the-art methods. Moreover, the experiments on in-vivo sequences demonstrate that the proposed method can tackle the difficult condition of tracking with unknown camera parameters. Further refinements of the method will refer to the occlusion and multi-instrumental MIS applications.
Analysis on the use of Multi-Sequence MRI Series for Segmentation of Abdominal Organs
NASA Astrophysics Data System (ADS)
Selver, M. A.; Selvi, E.; Kavur, E.; Dicle, O.
2015-01-01
Segmentation of abdominal organs from MRI data sets is a challenging task due to various limitations and artefacts. During the routine clinical practice, radiologists use multiple MR sequences in order to analyze different anatomical properties. These sequences have different characteristics in terms of acquisition parameters (such as contrast mechanisms and pulse sequence designs) and image properties (such as pixel spacing, slice thicknesses and dynamic range). For a complete understanding of the data, computational techniques should combine the information coming from these various MRI sequences. These sequences are not acquired in parallel but in a sequential manner (one after another). Therefore, patient movements and respiratory motions change the position and shape of the abdominal organs. In this study, the amount of these effects is measured using three different symmetric surface distance metrics performed to three dimensional data acquired from various MRI sequences. The results are compared to intra and inter observer differences and discussions on using multiple MRI sequences for segmentation and the necessities for registration are presented.
NASA Technical Reports Server (NTRS)
Snow, Walter L.; Childers, Brooks A.; Jones, Stephen B.; Fremaux, Charles M.
1993-01-01
A model space positioning system (MSPS), a state-of-the-art, real-time tracking system to provide the test engineer with on line model pitch and spin rate information, is described. It is noted that the six-degree-of-freedom post processor program will require additional programming effort both in the automated tracking mode for high spin rates and in accuracy to meet the measurement objectives. An independent multicamera system intended to augment the MSPS is studied using laboratory calibration methods based on photogrammetry to characterize the losses in various recording options. Data acquired to Super VHS tape encoded with Vertical Interval Time Code and transcribed to video disk are considered to be a reasonable priced choice for post editing and processing video data.
In-network adaptation of SHVC video in software-defined networks
NASA Astrophysics Data System (ADS)
Awobuluyi, Olatunde; Nightingale, James; Wang, Qi; Alcaraz Calero, Jose Maria; Grecos, Christos
2016-04-01
Software Defined Networks (SDN), when combined with Network Function Virtualization (NFV) represents a paradigm shift in how future networks will behave and be managed. SDN's are expected to provide the underpinning technologies for future innovations such as 5G mobile networks and the Internet of Everything. The SDN architecture offers features that facilitate an abstracted and centralized global network view in which packet forwarding or dropping decisions are based on application flows. Software Defined Networks facilitate a wide range of network management tasks, including the adaptation of real-time video streams as they traverse the network. SHVC, the scalable extension to the recent H.265 standard is a new video encoding standard that supports ultra-high definition video streams with spatial resolutions of up to 7680×4320 and frame rates of 60fps or more. The massive increase in bandwidth required to deliver these U-HD video streams dwarfs the bandwidth requirements of current high definition (HD) video. Such large bandwidth increases pose very significant challenges for network operators. In this paper we go substantially beyond the limited number of existing implementations and proposals for video streaming in SDN's all of which have primarily focused on traffic engineering solutions such as load balancing. By implementing and empirically evaluating an SDN enabled Media Adaptation Network Entity (MANE) we provide a valuable empirical insight into the benefits and limitations of SDN enabled video adaptation for real time video applications. The SDN-MANE is the video adaptation component of our Video Quality Assurance Manager (VQAM) SDN control plane application, which also includes an SDN monitoring component to acquire network metrics and a decision making engine using algorithms to determine the optimum adaptation strategy for any real time video application flow given the current network conditions. Our proposed VQAM application has been implemented and evaluated on an SDN allowing us to provide important benchmarks for video streaming over SDN and for SDN control plane latency.
NASA Astrophysics Data System (ADS)
Huber, Samuel; Dunau, Patrick; Wellig, Peter; Stein, Karin
2017-10-01
Background: In target detection, the success rates depend strongly on human observer performances. Two prior studies tested the contributions of target detection algorithms and prior training sessions. The aim of this Swiss-German cooperation study was to evaluate the dependency of human observer performance on the quality of supporting image analysis algorithms. Methods: The participants were presented 15 different video sequences. Their task was to detect all targets in the shortest possible time. Each video sequence showed a heavily cluttered simulated public area from a different viewing angle. In each video sequence, the number of avatars in the area was altered to 100, 150 and 200 subjects. The number of targets appearing was kept at 10%. The number of marked targets varied from 0, 5, 10, 20 up to 40 marked subjects while keeping the positive predictive value of the detection algorithm at 20%. During the task, workload level was assessed by applying an acoustic secondary task. Detection rates and detection times for the targets were analyzed using inferential statistics. Results: The study found Target Detection Time to increase and Target Detection Rates to decrease with increasing numbers of avatars. The same is true for the Secondary Task Reaction Time while there was no effect on Secondary Task Hit Rate. Furthermore, we found a trend for a u-shaped correlation between the numbers of markings and RTST indicating increased workload. Conclusion: The trial results may indicate useful criteria for the design of training and support of observers in observational tasks.
Tezer, Fadime Irsel; Agan, Kadriye; Borggraefe, Ingo; Noachtar, Soheyl
2013-09-01
This patient report demonstrates the importance of seizure evolution in the localising value of seizure semiology. Spread of epileptic activity from frontal to temporal lobe, as demonstrated by invasive recordings, was reflected by change from hyperkinetic movements to arrest of activity with mild oral and manual automatisms. [Published with video sequences].
Classification and Weakly Supervised Pain Localization using Multiple Segment Representation.
Sikka, Karan; Dhall, Abhinav; Bartlett, Marian Stewart
2014-10-01
Automatic pain recognition from videos is a vital clinical application and, owing to its spontaneous nature, poses interesting challenges to automatic facial expression recognition (AFER) research. Previous pain vs no-pain systems have highlighted two major challenges: (1) ground truth is provided for the sequence, but the presence or absence of the target expression for a given frame is unknown, and (2) the time point and the duration of the pain expression event(s) in each video are unknown. To address these issues we propose a novel framework (referred to as MS-MIL) where each sequence is represented as a bag containing multiple segments, and multiple instance learning (MIL) is employed to handle this weakly labeled data in the form of sequence level ground-truth. These segments are generated via multiple clustering of a sequence or running a multi-scale temporal scanning window, and are represented using a state-of-the-art Bag of Words (BoW) representation. This work extends the idea of detecting facial expressions through 'concept frames' to 'concept segments' and argues through extensive experiments that algorithms such as MIL are needed to reap the benefits of such representation. The key advantages of our approach are: (1) joint detection and localization of painful frames using only sequence-level ground-truth, (2) incorporation of temporal dynamics by representing the data not as individual frames but as segments, and (3) extraction of multiple segments, which is well suited to signals with uncertain temporal location and duration in the video. Extensive experiments on UNBC-McMaster Shoulder Pain dataset highlight the effectiveness of the approach by achieving competitive results on both tasks of pain classification and localization in videos. We also empirically evaluate the contributions of different components of MS-MIL. The paper also includes the visualization of discriminative facial patches, important for pain detection, as discovered by our algorithm and relates them to Action Units that have been associated with pain expression. We conclude the paper by demonstrating that MS-MIL yields a significant improvement on another spontaneous facial expression dataset, the FEEDTUM dataset.
Comparative study of methods for recognition of an unknown person's action from a video sequence
NASA Astrophysics Data System (ADS)
Hori, Takayuki; Ohya, Jun; Kurumisawa, Jun
2009-02-01
This paper proposes a Tensor Decomposition Based method that can recognize an unknown person's action from a video sequence, where the unknown person is not included in the database (tensor) used for the recognition. The tensor consists of persons, actions and time-series image features. For the observed unknown person's action, one of the actions stored in the tensor is assumed. Using the motion signature obtained from the assumption, the unknown person's actions are synthesized. The actions of one of the persons in the tensor are replaced by the synthesized actions. Then, the core tensor for the replaced tensor is computed. This process is repeated for the actions and persons. For each iteration, the difference between the replaced and original core tensors is computed. The assumption that gives the minimal difference is the action recognition result. For the time-series image features to be stored in the tensor and to be extracted from the observed video sequence, the human body silhouette's contour shape based feature is used. To show the validity of our proposed method, our proposed method is experimentally compared with Nearest Neighbor rule and Principal Component analysis based method. Experiments using 33 persons' seven kinds of action show that our proposed method achieves better recognition accuracies for the seven actions than the other methods.
NASA Astrophysics Data System (ADS)
Hasan, Taufiq; Bořil, Hynek; Sangwan, Abhijeet; L Hansen, John H.
2013-12-01
The ability to detect and organize `hot spots' representing areas of excitement within video streams is a challenging research problem when techniques rely exclusively on video content. A generic method for sports video highlight selection is presented in this study which leverages both video/image structure as well as audio/speech properties. Processing begins where the video is partitioned into small segments and several multi-modal features are extracted from each segment. Excitability is computed based on the likelihood of the segmental features residing in certain regions of their joint probability density function space which are considered both exciting and rare. The proposed measure is used to rank order the partitioned segments to compress the overall video sequence and produce a contiguous set of highlights. Experiments are performed on baseball videos based on signal processing advancements for excitement assessment in the commentators' speech, audio energy, slow motion replay, scene cut density, and motion activity as features. Detailed analysis on correlation between user excitability and various speech production parameters is conducted and an effective scheme is designed to estimate the excitement level of commentator's speech from the sports videos. Subjective evaluation of excitability and ranking of video segments demonstrate a higher correlation with the proposed measure compared to well-established techniques indicating the effectiveness of the overall approach.
Video-based face recognition via convolutional neural networks
NASA Astrophysics Data System (ADS)
Bao, Tianlong; Ding, Chunhui; Karmoshi, Saleem; Zhu, Ming
2017-06-01
Face recognition has been widely studied recently while video-based face recognition still remains a challenging task because of the low quality and large intra-class variation of video captured face images. In this paper, we focus on two scenarios of video-based face recognition: 1)Still-to-Video(S2V) face recognition, i.e., querying a still face image against a gallery of video sequences; 2)Video-to-Still(V2S) face recognition, in contrast to S2V scenario. A novel method was proposed in this paper to transfer still and video face images to an Euclidean space by a carefully designed convolutional neural network, then Euclidean metrics are used to measure the distance between still and video images. Identities of still and video images that group as pairs are used as supervision. In the training stage, a joint loss function that measures the Euclidean distance between the predicted features of training pairs and expanding vectors of still images is optimized to minimize the intra-class variation while the inter-class variation is guaranteed due to the large margin of still images. Transferred features are finally learned via the designed convolutional neural network. Experiments are performed on COX face dataset. Experimental results show that our method achieves reliable performance compared with other state-of-the-art methods.
McCormick, Paul C
2014-09-01
Dumbbell tumors of the cervical spine can present considerable management challenges related to adequate exposure of both intraspinal and paraspinal tumor components, potential injury to the vertebral artery, and spinal stability. This video demonstrates the microsurgical removal of a large cervical dumbbell schwannoma with instrumented fusion via a single stage extended posterior approach. The video shows patient positioning, tumor exposure, and the sequence and techniques of tumor resection, vertebral artery identification and protection, and dural repair. The video can be found here: http://youtu.be/3lIVfKEcxss.
Self-induced stretch syncope of adolescence: a video-EEG documentation.
Mazzuca, Michel; Thomas, Pierre
2007-12-01
We present the first video-EEG documentation, with ECG and EMG features, of stretch syncope of adolescence in a young, healthy 16-year-old boy. Stretch syncope of adolescence is a rarely reported, benign cause of fainting in young patients, which can be confused with epileptic seizures. In our patient, syncopes were self-induced to avoid school. Dynamic transcranial Doppler showed evidence of blood flow decrease in both posterior cerebral arteries mimicking effects of a Valsalva manoeuvre. Dynamic angiogram of the vertebral arteries was normal. Hypotheses concerning the physiopathology are discussed. [Published with video sequences].
Registration of retinal sequences from new video-ophthalmoscopic camera.
Kolar, Radim; Tornow, Ralf P; Odstrcilik, Jan; Liberdova, Ivana
2016-05-20
Analysis of fast temporal changes on retinas has become an important part of diagnostic video-ophthalmology. It enables investigation of the hemodynamic processes in retinal tissue, e.g. blood-vessel diameter changes as a result of blood-pressure variation, spontaneous venous pulsation influenced by intracranial-intraocular pressure difference, blood-volume changes as a result of changes in light reflection from retinal tissue, and blood flow using laser speckle contrast imaging. For such applications, image registration of the recorded sequence must be performed. Here we use a new non-mydriatic video-ophthalmoscope for simple and fast acquisition of low SNR retinal sequences. We introduce a novel, two-step approach for fast image registration. The phase correlation in the first stage removes large eye movements. Lucas-Kanade tracking in the second stage removes small eye movements. We propose robust adaptive selection of the tracking points, which is the most important part of tracking-based approaches. We also describe a method for quantitative evaluation of the registration results, based on vascular tree intensity profiles. The achieved registration error evaluated on 23 sequences (5840 frames) is 0.78 ± 0.67 pixels inside the optic disc and 1.39 ± 0.63 pixels outside the optic disc. We compared the results with the commonly used approaches based on Lucas-Kanade tracking and scale-invariant feature transform, which achieved worse results. The proposed method can efficiently correct particular frames of retinal sequences for shift and rotation. The registration results for each frame (shift in X and Y direction and eye rotation) can also be used for eye-movement evaluation during single-spot fixation tasks.
Picardi, N
1999-01-01
The facility of the tape recording of a surgical operation, by means of simple manageable apparatuses and at low costs, especially in comparison with the former cinematography, makes it possible for all surgeons to record their own operative activity. Therefore at present the demonstration in video of surgical interventions is very common, but very often the video-tapes show surgical events only in straight chronological succession, as for facts of chronicle news. The simplification of the otherwise sophisticated digital technology of informatics elaboration of images makes more convenient and advisable to assemble the more meaningful sequences for a final product of higher scientific value. The digital technology gives at the best its contribution during the phase of post-production of the video-tape, where the surgeon himself can assemble an end product of more value because aimed to a scientific and rational communication. Thanks to such an elaboration the video-tape can aim not simply to become a good documentary, but also to achieve an educational purpose or becomes a truly scientific film. The initial video will be recorded following a specific project, the script, foreseeing and programming what has to be demonstrated of the surgical operation, establishing therefore in advance the most important steps of the intervention. The sequences recorded will then be assembled not necessarily in a chronological succession but integrating the moving images with static pictures, as drawings, schemes, tables, aside the picture-in picture technique, and besides the vocal descriptive comment. The cinema language has accustomed us to a series of passages among the different sequences as fading, cross-over, "flash-back", aiming to stimulate the psychological associative powers and encourage those critical. The video-tape can be opportunely shortened, paying attention to show only the essential phases of the operation for demonstrate only the core of the problem and utilize at the best the physiological period of active attention of the observer. The informatic digital elaboration has become so easy that the surgeon himself can be able to elaborate personally on his personal computer, with professional and scientific attitude, the sequences of his surgical activity in a product of more general value. His personal engagement also in the phase of post-production gives him the possibility to demonstrate uprightly with images the complex surgical experience of science, skill and ability to communicate, perhaps better than he is able to do with words.
NASA Astrophysics Data System (ADS)
Taj-Eddin, Islam A. T. F.; Afifi, Mahmoud; Korashy, Mostafa; Ahmed, Ali H.; Cheng, Ng Yoke; Hernandez, Evelyng; Abdel-Latif, Salma M.
2017-11-01
Plant aliveness is proven through laboratory experiments and special scientific instruments. We aim to detect the degree of animation of plants based on the magnification of the small color changes in the plant's green leaves using the Eulerian video magnification. Capturing the video under a controlled environment, e.g., using a tripod and direct current light sources, reduces camera movements and minimizes light fluctuations; we aim to reduce the external factors as much as possible. The acquired video is then stabilized and a proposed algorithm is used to reduce the illumination variations. Finally, the Euler magnification is utilized to magnify the color changes on the light invariant video. The proposed system does not require any special purpose instruments as it uses a digital camera with a regular frame rate. The results of magnified color changes on both natural and plastic leaves show that the live green leaves have color changes in contrast to the plastic leaves. Hence, we can argue that the color changes of the leaves are due to biological operations, such as photosynthesis. To date, this is possibly the first work that focuses on interpreting visually, some biological operations of plants without any special purpose instruments.
Detection of artery interfaces: a real-time system and its clinical applications
NASA Astrophysics Data System (ADS)
Faita, Francesco; Gemignani, Vincenzo; Bianchini, Elisabetta; Giannarelli, Chiara; Ghiadoni, Lorenzo; Demi, Marcello
2008-03-01
Analyzing the artery mechanics is a crucial issue because of its close relationship with several cardiovascular risk factors, such as hypertension and diabetes. Moreover, most of the work can be carried out by analyzing image sequences obtained with ultrasounds, that is with a non-invasive technique which allows a real-time visualization of the observed structures. For this reason, therefore, an accurate temporal localization of the main vessel interfaces becomes a central task for which the manual approach should be avoided since such a method is rather unreliable and time consuming. Real-time automatic systems are advantageously used to automatically locate the arterial interfaces. The automatic measurement reduces the inter/intra-observer variability with respect to the manual measurement which unavoidably depends on the experience of the operator. The real-time visual feedback, moreover, guides physicians when looking for the best position of the ultrasound probe, thus increasing the global robustness of the system. The automatic system which we developed is a stand-alone video processing system which acquires the analog video signal from the ultrasound equipment, performs all the measurements and shows the results in real-time. The localization algorithm of the artery tunics is based on a new mathematical operator (the first order absolute moment) and on a pattern recognition approach. Various clinical applications have been developed on board and validated through a comparison with gold-standard techniques: the assessment of intima-media thickness, the arterial distension, the flow-mediated dilation and the pulse wave velocity. With this paper, the results obtained on clinical trials are presented.
Human recognition based on head-shoulder contour extraction and BP neural network
NASA Astrophysics Data System (ADS)
Kong, Xiao-fang; Wang, Xiu-qin; Gu, Guohua; Chen, Qian; Qian, Wei-xian
2014-11-01
In practical application scenarios like video surveillance and human-computer interaction, human body movements are uncertain because the human body is a non-rigid object. Based on the fact that the head-shoulder part of human body can be less affected by the movement, and will seldom be obscured by other objects, in human detection and recognition, a head-shoulder model with its stable characteristics can be applied as a detection feature to describe the human body. In order to extract the head-shoulder contour accurately, a head-shoulder model establish method with combination of edge detection and the mean-shift algorithm in image clustering has been proposed in this paper. First, an adaptive method of mixture Gaussian background update has been used to extract targets from the video sequence. Second, edge detection has been used to extract the contour of moving objects, and the mean-shift algorithm has been combined to cluster parts of target's contour. Third, the head-shoulder model can be established, according to the width and height ratio of human head-shoulder combined with the projection histogram of the binary image, and the eigenvectors of the head-shoulder contour can be acquired. Finally, the relationship between head-shoulder contour eigenvectors and the moving objects will be formed by the training of back-propagation (BP) neural network classifier, and the human head-shoulder model can be clustered for human detection and recognition. Experiments have shown that the method combined with edge detection and mean-shift algorithm proposed in this paper can extract the complete head-shoulder contour, with low calculating complexity and high efficiency.
Video-tracker trajectory analysis: who meets whom, when and where
NASA Astrophysics Data System (ADS)
Jäger, U.; Willersinn, D.
2010-04-01
Unveiling unusual or hostile events by observing manifold moving persons in a crowd is a challenging task for human operators, especially when sitting in front of monitor walls for hours. Typically, hostile events are rare. Thus, due to tiredness and negligence the operator may miss important events. In such situations, an automatic alarming system is able to support the human operator. The system incorporates a processing chain consisting of (1) people tracking, (2) event detection, (3) data retrieval, and (4) display of relevant video sequence overlaid by highlighted regions of interest. In this paper we focus on the event detection stage of the processing chain mentioned above. In our case, the selected event of interest is the encounter of people. Although being based on a rather simple trajectory analysis, this kind of event embodies great practical importance because it paves the way to answer the question "who meets whom, when and where". This, in turn, forms the basis to detect potential situations where e.g. money, weapons, drugs etc. are handed over from one person to another in crowded environments like railway stations, airports or busy streets and places etc.. The input to the trajectory analysis comes from a multi-object video-based tracking system developed at IOSB which is able to track multiple individuals within a crowd in real-time [1]. From this we calculate the inter-distances between all persons on a frame-to-frame basis. We use a sequence of simple rules based on the individuals' kinematics to detect the event mentioned above to output the frame number, the persons' IDs from the tracker and the pixel coordinates of the meeting position. Using this information, a data retrieval system may extract the corresponding part of the recorded video image sequence and finally allows for replaying the selected video clip with a highlighted region of interest to attract the operator's attention for further visual inspection.
Temporal flicker reduction and denoising in video using sparse directional transforms
NASA Astrophysics Data System (ADS)
Kanumuri, Sandeep; Guleryuz, Onur G.; Civanlar, M. Reha; Fujibayashi, Akira; Boon, Choong S.
2008-08-01
The bulk of the video content available today over the Internet and over mobile networks suffers from many imperfections caused during acquisition and transmission. In the case of user-generated content, which is typically produced with inexpensive equipment, these imperfections manifest in various ways through noise, temporal flicker and blurring, just to name a few. Imperfections caused by compression noise and temporal flicker are present in both studio-produced and user-generated video content transmitted at low bit-rates. In this paper, we introduce an algorithm designed to reduce temporal flicker and noise in video sequences. The algorithm takes advantage of the sparse nature of video signals in an appropriate transform domain that is chosen adaptively based on local signal statistics. When the signal corresponds to a sparse representation in this transform domain, flicker and noise, which are spread over the entire domain, can be reduced easily by enforcing sparsity. Our results show that the proposed algorithm reduces flicker and noise significantly and enables better presentation of compressed videos.
Video documentation of experiments at the USGS debris-flow flume 1992–2017
Logan, Matthew; Iverson, Richard M.
2007-11-23
This set of videos presents about 18 hours of footage documenting the 163 experiments conducted at the USGS debris-flow flume from 1992 to 2017. Owing to improvements in video technology over the years, the quality of footage from recent experiments generally exceeds that from earlier experiments.Use the list below to access the individual videos, which are mostly grouped by date and subject matter. When a video is selected from the list, multiple video sequences are generally shown in succession, beginning with a far-field overview and proceeding to close-up views and post-experiment documentation.Interpretations and data from experiments at the USGS debris-flow flume are not provided here but can be found in published reports, many of which are available online at: https://profile.usgs.gov/riverson/A brief introduction to the flume facility is also available online in USGS Open-File Report 92–483 [http://pubs.er.usgs.gov/usgspubs/ofr/ofr92483].
NASA Astrophysics Data System (ADS)
Duplaga, M.; Leszczuk, M. I.; Papir, Z.; Przelaskowski, A.
2008-12-01
Wider dissemination of medical digital video libraries is affected by two correlated factors, resource effective content compression that directly influences its diagnostic credibility. It has been proved that it is possible to meet these contradictory requirements halfway for long-lasting and low motion surgery recordings at compression ratios close to 100 (bronchoscopic procedures were a case study investigated). As the main supporting assumption, it has been accepted that the content can be compressed as far as clinicians are not able to sense a loss of video diagnostic fidelity (a visually lossless compression). Different market codecs were inspected by means of the combined subjective and objective tests toward their usability in medical video libraries. Subjective tests involved a panel of clinicians who had to classify compressed bronchoscopic video content according to its quality under the bubble sort algorithm. For objective tests, two metrics (hybrid vector measure and hosaka Plots) were calculated frame by frame and averaged over a whole sequence.
Authoring Data-Driven Videos with DataClips.
Amini, Fereshteh; Riche, Nathalie Henry; Lee, Bongshin; Monroy-Hernandez, Andres; Irani, Pourang
2017-01-01
Data videos, or short data-driven motion graphics, are an increasingly popular medium for storytelling. However, creating data videos is difficult as it involves pulling together a unique combination of skills. We introduce DataClips, an authoring tool aimed at lowering the barriers to crafting data videos. DataClips allows non-experts to assemble data-driven "clips" together to form longer sequences. We constructed the library of data clips by analyzing the composition of over 70 data videos produced by reputable sources such as The New York Times and The Guardian. We demonstrate that DataClips can reproduce over 90% of our data videos corpus. We also report on a qualitative study comparing the authoring process and outcome achieved by (1) non-experts using DataClips, and (2) experts using Adobe Illustrator and After Effects to create data-driven clips. Results indicated that non-experts are able to learn and use DataClips with a short training period. In the span of one hour, they were able to produce more videos than experts using a professional editing tool, and their clips were rated similarly by an independent audience.
Detection of distorted frames in retinal video-sequences via machine learning
NASA Astrophysics Data System (ADS)
Kolar, Radim; Liberdova, Ivana; Odstrcilik, Jan; Hracho, Michal; Tornow, Ralf P.
2017-07-01
This paper describes detection of distorted frames in retinal sequences based on set of global features extracted from each frame. The feature vector is consequently used in classification step, in which three types of classifiers are tested. The best classification accuracy 96% has been achieved with support vector machine approach.
Authentic L2 Interactions as Material for a Pragmatic Awareness-Raising Activity
ERIC Educational Resources Information Center
Cheng, Tsui-Ping
2016-01-01
This study draws on conversation analysis to explore the pedagogical possibility of using audiovisual depictions of authentic disagreement sequences from L2 interactions as sources for an awareness-raising activity in an English as a Second Language (ESL) classroom. Video excerpts of disagreement sequences collected from two ESL classes were used…
Using video-oriented instructions to speed up sequence comparison.
Wozniak, A
1997-04-01
This document presents an implementation of the well-known Smith-Waterman algorithm for comparison of proteic and nucleic sequences, using specialized video instructions. These instructions, SIMD-like in their design, make possible parallelization of the algorithm at the instruction level. Benchmarks on an ULTRA SPARC running at 167 MHz show a speed-up factor of two compared to the same algorithm implemented with integer instructions on the same machine. Performance reaches over 18 million matrix cells per second on a single processor, giving to our knowledge the fastest implementation of the Smith-Waterman algorithm on a workstation. The accelerated procedure was introduced in LASSAP--a LArge Scale Sequence compArison Package software developed at INRIA--which handles parallelism at higher level. On a SUN Enterprise 6000 server with 12 processors, a speed of nearly 200 million matrix cells per second has been obtained. A sequence of length 300 amino acids is scanned against SWISSPROT R33 (1,8531,385 residues) in 29 s. This procedure is not restricted to databank scanning. It applies to all cases handled by LASSAP (intra- and inter-bank comparisons, Z-score computation, etc.
Hierarchical structure for audio-video based semantic classification of sports video sequences
NASA Astrophysics Data System (ADS)
Kolekar, M. H.; Sengupta, S.
2005-07-01
A hierarchical structure for sports event classification based on audio and video content analysis is proposed in this paper. Compared to the event classifications in other games, those of cricket are very challenging and yet unexplored. We have successfully solved cricket video classification problem using a six level hierarchical structure. The first level performs event detection based on audio energy and Zero Crossing Rate (ZCR) of short-time audio signal. In the subsequent levels, we classify the events based on video features using a Hidden Markov Model implemented through Dynamic Programming (HMM-DP) using color or motion as a likelihood function. For some of the game-specific decisions, a rule-based classification is also performed. Our proposed hierarchical structure can easily be applied to any other sports. Our results are very promising and we have moved a step forward towards addressing semantic classification problems in general.
Privacy enabling technology for video surveillance
NASA Astrophysics Data System (ADS)
Dufaux, Frédéric; Ouaret, Mourad; Abdeljaoued, Yousri; Navarro, Alfonso; Vergnenègre, Fabrice; Ebrahimi, Touradj
2006-05-01
In this paper, we address the problem privacy in video surveillance. We propose an efficient solution based on transformdomain scrambling of regions of interest in a video sequence. More specifically, the sign of selected transform coefficients is flipped during encoding. We address more specifically the case of Motion JPEG 2000. Simulation results show that the technique can be successfully applied to conceal information in regions of interest in the scene while providing with a good level of security. Furthermore, the scrambling is flexible and allows adjusting the amount of distortion introduced. This is achieved with a small impact on coding performance and negligible computational complexity increase. In the proposed video surveillance system, heterogeneous clients can remotely access the system through the Internet or 2G/3G mobile phone network. Thanks to the inherently scalable Motion JPEG 2000 codestream, the server is able to adapt the resolution and bandwidth of the delivered video depending on the usage environment of the client.
Design and implementation of a non-linear symphonic soundtrack of a video game
NASA Astrophysics Data System (ADS)
Sporka, Adam J.; Valta, Jan
2017-10-01
The music in the contemporary video games is often interactive. The music playback is based on transitions between pieces of available music material. These transitions happen in response to evolving gameplay. This paradigm is referred to as the adaptive music. Our challenge was to design, create, and implement the soundtrack of the upcoming video game Kingdom Come: Deliverance. Our soundtrack is a collection of compositions with symphonic orchestration. Per our design decision, our intention was to implement the adaptive music in a way which respected the nature of the orchestral film score. We created our own adaptive music middleware, called Sequence Music Engine, implementing a high-level music logic as well as the low-level playback infrastructure. Our system can handle hours of video game music, helps maintain the relevance of the music throughout the video game, and minimises the repetitiveness of the individual pieces.
Library orientation on videotape: production planning and administrative support.
Shedlock, J; Tawyea, E W
1989-01-01
New student-faculty-staff orientation is an important public service in a medical library and demands creativity, imagination, teaching skill, coordination, and cooperation on the part of public services staff. The Northwestern University Medical Library (NUML) implemented a video production service in the spring of 1986 and used the new service to produce an orientation videotape for incoming students, new faculty, and medical center staff. Planning is an important function in video production, and the various phases of outlining topics, drafting scripts, matching video sequences, and actual taping of video, voice, and music are described. The NUML orientation videotape demonstrates how reference and audiovisual services merge talent and skills to benefit the library user. Videotape production, however, cannot happen in a vacuum of good intentions and high ideals. This paper also presents the management support and cost analysis needed to make video production services a reality for use by public service departments.
Video watermarking for mobile phone applications
NASA Astrophysics Data System (ADS)
Mitrea, M.; Duta, S.; Petrescu, M.; Preteux, F.
2005-08-01
Nowadays, alongside with the traditional voice signal, music, video, and 3D characters tend to become common data to be run, stored and/or processed on mobile phones. Hence, to protect their related intellectual property rights also becomes a crucial issue. The video sequences involved in such applications are generally coded at very low bit rates. The present paper starts by presenting an accurate statistical investigation on such a video as well as on a very dangerous attack (the StirMark attack). The obtained results are turned into practice when adapting a spread spectrum watermarking method to such applications. The informed watermarking approach was also considered: an outstanding method belonging to this paradigm has been adapted and re evaluated under the low rate video constraint. The experimental results were conducted in collaboration with the SFR mobile services provider in France. They also allow a comparison between the spread spectrum and informed embedding techniques.
Characterization, adaptive traffic shaping, and multiplexing of real-time MPEG II video
NASA Astrophysics Data System (ADS)
Agrawal, Sanjay; Barry, Charles F.; Binnai, Vinay; Kazovsky, Leonid G.
1997-01-01
We obtain network traffic model for real-time MPEG-II encoded digital video by analyzing video stream samples from real-time encoders from NUKO Information Systems. MPEG-II sample streams include a resolution intensive movie, City of Joy, an action intensive movie, Aliens, a luminance intensive (black and white) movie, Road To Utopia, and a chrominance intensive (color) movie, Dick Tracy. From our analysis we obtain a heuristic model for the encoded video traffic which uses a 15-stage Markov process to model the I,B,P frame sequences within a group of pictures (GOP). A jointly-correlated Gaussian process is used to model the individual frame sizes. Scene change arrivals are modeled according to a gamma process. Simulations show that our MPEG-II traffic model generates, I,B,P frame sequences and frame sizes that closely match the sample MPEG-II stream traffic characteristics as they relate to latency and buffer occupancy in network queues. To achieve high multiplexing efficiency we propose a traffic shaping scheme which sets preferred 1-frame generation times among a group of encoders so as to minimize the overall variation in total offered traffic while still allowing the individual encoders to react to scene changes. Simulations show that our scheme results in multiplexing gains of up to 10% enabling us to multiplex twenty 6 Mbps MPEG-II video streams instead of 18 streams over an ATM/SONET OC3 link without latency or cell loss penalty. This scheme is due for a patent.
Quality and noise measurements in mobile phone video capture
NASA Astrophysics Data System (ADS)
Petrescu, Doina; Pincenti, John
2011-02-01
The quality of videos captured with mobile phones has become increasingly important particularly since resolutions and formats have reached a level that rivals the capabilities available in the digital camcorder market, and since many mobile phones now allow direct playback on large HDTVs. The video quality is determined by the combined quality of the individual parts of the imaging system including the image sensor, the digital color processing, and the video compression, each of which has been studied independently. In this work, we study the combined effect of these elements on the overall video quality. We do this by evaluating the capture under various lighting, color processing, and video compression conditions. First, we measure full reference quality metrics between encoder input and the reconstructed sequence, where the encoder input changes with light and color processing modifications. Second, we introduce a system model which includes all elements that affect video quality, including a low light additive noise model, ISP color processing, as well as the video encoder. Our experiments show that in low light conditions and for certain choices of color processing the system level visual quality may not improve when the encoder becomes more capable or the compression ratio is reduced.
Research on compression performance of ultrahigh-definition videos
NASA Astrophysics Data System (ADS)
Li, Xiangqun; He, Xiaohai; Qing, Linbo; Tao, Qingchuan; Wu, Di
2017-11-01
With the popularization of high-definition (HD) images and videos (1920×1080 pixels and above), there are even 4K (3840×2160) television signals and 8 K (8192×4320) ultrahigh-definition videos. The demand for HD images and videos is increasing continuously, along with the increasing data volume. The storage and transmission cannot be properly solved only by virtue of the expansion capacity of hard disks and the update and improvement of transmission devices. Based on the full use of the coding standard high-efficiency video coding (HEVC), super-resolution reconstruction technology, and the correlation between the intra- and the interprediction, we first put forward a "division-compensation"-based strategy to further improve the compression performance of a single image and frame I. Then, by making use of the above thought and HEVC encoder and decoder, a video compression coding frame is designed. HEVC is used inside the frame. Last, with the super-resolution reconstruction technology, the reconstructed video quality is further improved. The experiment shows that by the proposed compression method for a single image (frame I) and video sequence here, the performance is superior to that of HEVC in a low bit rate environment.
A preliminary experiment definition for video landmark acquisition and tracking
NASA Technical Reports Server (NTRS)
Schappell, R. T.; Tietz, J. C.; Hulstrom, R. L.; Cunningham, R. A.; Reel, G. M.
1976-01-01
Six scientific objectives/experiments were derived which consisted of agriculture/forestry/range resources, land use, geology/mineral resources, water resources, marine resources and environmental surveys. Computer calculations were then made of the spectral radiance signature of each of 25 candidate targets as seen by a satellite sensor system. An imaging system capable of recognizing, acquiring and tracking specific generic type surface features was defined. A preliminary experiment definition and design of a video Landmark Acquisition and Tracking system is given. This device will search a 10-mile swath while orbiting the earth, looking for land/water interfaces such as coastlines and rivers.
Doulamis, A; Doulamis, N; Ntalianis, K; Kollias, S
2003-01-01
In this paper, an unsupervised video object (VO) segmentation and tracking algorithm is proposed based on an adaptable neural-network architecture. The proposed scheme comprises: 1) a VO tracking module and 2) an initial VO estimation module. Object tracking is handled as a classification problem and implemented through an adaptive network classifier, which provides better results compared to conventional motion-based tracking algorithms. Network adaptation is accomplished through an efficient and cost effective weight updating algorithm, providing a minimum degradation of the previous network knowledge and taking into account the current content conditions. A retraining set is constructed and used for this purpose based on initial VO estimation results. Two different scenarios are investigated. The first concerns extraction of human entities in video conferencing applications, while the second exploits depth information to identify generic VOs in stereoscopic video sequences. Human face/ body detection based on Gaussian distributions is accomplished in the first scenario, while segmentation fusion is obtained using color and depth information in the second scenario. A decision mechanism is also incorporated to detect time instances for weight updating. Experimental results and comparisons indicate the good performance of the proposed scheme even in sequences with complicated content (object bending, occlusion).
Fire behavior sensor package remote trigger design
Dan Jimenez; Jason Forthofer; James Reardon; Bret Butler
2007-01-01
Fire behavior characteristics (such as temperature, radiant and total heat flux, 2- and 3-dimensional velocities, and air flow) are extremely difficult to measure insitu. Although insitu sensor packages are capable of such measurements in realtime, it is also essential to acquire video documentation as a means of better understanding the fire behavior data recorded by...
Tse, Karen; Grant, Claire; Keerie, Amy; Simpson, David J.; Pedersen, John C.; Rimmer, Victoria; Leslie, Lauren; Klein, Stephanie K.; Karp, Natasha A.; Sillito, Rowland; Chartsias, Agis; Lukins, Tim; Heward, James; Vickers, Catherine; Chapman, Kathryn; Armstrong, J. Douglas
2017-01-01
Measuring the activity and temperature of rats is commonly required in biomedical research. Conventional approaches necessitate single housing, which affects their behavior and wellbeing. We have used a subcutaneous radiofrequency identification (RFID) transponder to measure ambulatory activity and temperature of individual rats when group-housed in conventional, rack-mounted home cages. The transponder location and temperature is detected by a matrix of antennae in a baseplate under the cage. An infrared high-definition camera acquires side-view video of the cage and also enables automated detection of vertical activity. Validation studies showed that baseplate-derived ambulatory activity correlated well with manual tracking and with side-view whole-cage video pixel movement. This technology enables individual behavioral and temperature data to be acquired continuously from group-housed rats in their familiar, home cage environment. We demonstrate its ability to reliably detect naturally occurring behavioral effects, extending beyond the capabilities of routine observational tests and conventional monitoring equipment. It has numerous potential applications including safety pharmacology, toxicology, circadian biology, disease models and drug discovery. PMID:28877172
NASA Astrophysics Data System (ADS)
Terzopoulos, Demetri; Qureshi, Faisal Z.
Computer vision and sensor networks researchers are increasingly motivated to investigate complex multi-camera sensing and control issues that arise in the automatic visual surveillance of extensive, highly populated public spaces such as airports and train stations. However, they often encounter serious impediments to deploying and experimenting with large-scale physical camera networks in such real-world environments. We propose an alternative approach called "Virtual Vision", which facilitates this type of research through the virtual reality simulation of populated urban spaces, camera sensor networks, and computer vision on commodity computers. We demonstrate the usefulness of our approach by developing two highly automated surveillance systems comprising passive and active pan/tilt/zoom cameras that are deployed in a virtual train station environment populated by autonomous, lifelike virtual pedestrians. The easily reconfigurable virtual cameras distributed in this environment generate synthetic video feeds that emulate those acquired by real surveillance cameras monitoring public spaces. The novel multi-camera control strategies that we describe enable the cameras to collaborate in persistently observing pedestrians of interest and in acquiring close-up videos of pedestrians in designated areas.
Redfern, William S; Tse, Karen; Grant, Claire; Keerie, Amy; Simpson, David J; Pedersen, John C; Rimmer, Victoria; Leslie, Lauren; Klein, Stephanie K; Karp, Natasha A; Sillito, Rowland; Chartsias, Agis; Lukins, Tim; Heward, James; Vickers, Catherine; Chapman, Kathryn; Armstrong, J Douglas
2017-01-01
Measuring the activity and temperature of rats is commonly required in biomedical research. Conventional approaches necessitate single housing, which affects their behavior and wellbeing. We have used a subcutaneous radiofrequency identification (RFID) transponder to measure ambulatory activity and temperature of individual rats when group-housed in conventional, rack-mounted home cages. The transponder location and temperature is detected by a matrix of antennae in a baseplate under the cage. An infrared high-definition camera acquires side-view video of the cage and also enables automated detection of vertical activity. Validation studies showed that baseplate-derived ambulatory activity correlated well with manual tracking and with side-view whole-cage video pixel movement. This technology enables individual behavioral and temperature data to be acquired continuously from group-housed rats in their familiar, home cage environment. We demonstrate its ability to reliably detect naturally occurring behavioral effects, extending beyond the capabilities of routine observational tests and conventional monitoring equipment. It has numerous potential applications including safety pharmacology, toxicology, circadian biology, disease models and drug discovery.
Introduction to study and simulation of low rate video coding schemes
NASA Technical Reports Server (NTRS)
1992-01-01
During this period, the development of simulators for the various HDTV systems proposed to the FCC were developed. These simulators will be tested using test sequences from the MPEG committee. The results will be extrapolated to HDTV video sequences. Currently, the simulator for the compression aspects of the Advanced Digital Television (ADTV) was completed. Other HDTV proposals are at various stages of development. A brief overview of the ADTV system is given. Some coding results obtained using the simulator are discussed. These results are compared to those obtained using the CCITT H.261 standard. These results in the context of the CCSDS specifications are evaluated and some suggestions as to how the ADTV system could be implemented in the NASA network are made.
SIRSALE: integrated video database management tools
NASA Astrophysics Data System (ADS)
Brunie, Lionel; Favory, Loic; Gelas, J. P.; Lefevre, Laurent; Mostefaoui, Ahmed; Nait-Abdesselam, F.
2002-07-01
Video databases became an active field of research during the last decade. The main objective in such systems is to provide users with capabilities to friendly search, access and playback distributed stored video data in the same way as they do for traditional distributed databases. Hence, such systems need to deal with hard issues : (a) video documents generate huge volumes of data and are time sensitive (streams must be delivered at a specific bitrate), (b) contents of video data are very hard to be automatically extracted and need to be humanly annotated. To cope with these issues, many approaches have been proposed in the literature including data models, query languages, video indexing etc. In this paper, we present SIRSALE : a set of video databases management tools that allow users to manipulate video documents and streams stored in large distributed repositories. All the proposed tools are based on generic models that can be customized for specific applications using ad-hoc adaptation modules. More precisely, SIRSALE allows users to : (a) browse video documents by structures (sequences, scenes, shots) and (b) query the video database content by using a graphical tool, adapted to the nature of the target video documents. This paper also presents an annotating interface which allows archivists to describe the content of video documents. All these tools are coupled to a video player integrating remote VCR functionalities and are based on active network technology. So, we present how dedicated active services allow an optimized video transport for video streams (with Tamanoir active nodes). We then describe experiments of using SIRSALE on an archive of news video and soccer matches. The system has been demonstrated to professionals with a positive feedback. Finally, we discuss open issues and present some perspectives.
Ethernet direct display: a new dimension for in-vehicle video connectivity solutions
NASA Astrophysics Data System (ADS)
Rowley, Vincent
2009-05-01
To improve the local situational awareness (LSA) of personnel in light or heavily armored vehicles, most military organizations recognize the need to equip their fleets with high-resolution digital video systems. Several related upgrade programs are already in progress and, almost invariably, COTS IP/Ethernet is specified as the underlying transport mechanism. The high bandwidths, long reach, networking flexibility, scalability, and affordability of IP/Ethernet make it an attractive choice. There are significant technical challenges, however, in achieving high-performance, real-time video connectivity over the IP/Ethernet platform. As an early pioneer in performance-oriented video systems based on IP/Ethernet, Pleora Technologies has developed core expertise in meeting these challenges and applied a singular focus to innovating within the required framework. The company's field-proven iPORTTM Video Connectivity Solution is deployed successfully in thousands of real-world applications for medical, military, and manufacturing operations. Pleora's latest innovation is eDisplayTM, a smallfootprint, low-power, highly efficient IP engine that acquires video from an Ethernet connection and sends it directly to a standard HDMI/DVI monitor for real-time viewing. More costly PCs are not required. This paper describes Pleora's eDisplay IP Engine in more detail. It demonstrates how - in concert with other elements of the end-to-end iPORT Video Connectivity Solution - the engine can be used to build standards-based, in-vehicle video systems that increase the safety and effectiveness of military personnel while fully leveraging the advantages of the lowcost COTS IP/Ethernet platform.
Knowledge-based understanding of aerial surveillance video
NASA Astrophysics Data System (ADS)
Cheng, Hui; Butler, Darren
2006-05-01
Aerial surveillance has long been used by the military to locate, monitor and track the enemy. Recently, its scope has expanded to include law enforcement activities, disaster management and commercial applications. With the ever-growing amount of aerial surveillance video acquired daily, there is an urgent need for extracting actionable intelligence in a timely manner. Furthermore, to support high-level video understanding, this analysis needs to go beyond current approaches and consider the relationships, motivations and intentions of the objects in the scene. In this paper we propose a system for interpreting aerial surveillance videos that automatically generates a succinct but meaningful description of the observed regions, objects and events. For a given video, the semantics of important regions and objects, and the relationships between them, are summarised into a semantic concept graph. From this, a textual description is derived that provides new search and indexing options for aerial video and enables the fusion of aerial video with other information modalities, such as human intelligence, reports and signal intelligence. Using a Mixture-of-Experts video segmentation algorithm an aerial video is first decomposed into regions and objects with predefined semantic meanings. The objects are then tracked and coerced into a semantic concept graph and the graph is summarized spatially, temporally and semantically using ontology guided sub-graph matching and re-writing. The system exploits domain specific knowledge and uses a reasoning engine to verify and correct the classes, identities and semantic relationships between the objects. This approach is advantageous because misclassifications lead to knowledge contradictions and hence they can be easily detected and intelligently corrected. In addition, the graph representation highlights events and anomalies that a low-level analysis would overlook.
Effects of action video game training on visual working memory.
Blacker, Kara J; Curby, Kim M; Klobusicky, Elizabeth; Chein, Jason M
2014-10-01
The ability to hold visual information in mind over a brief delay is critical for acquiring information and navigating a complex visual world. Despite the ubiquitous nature of visual working memory (VWM) in our everyday lives, this system is fundamentally limited in capacity. Therefore, the potential to improve VWM through training is a growing area of research. An emerging body of literature suggests that extensive experience playing action video games yields a myriad of perceptual and attentional benefits. Several lines of converging work suggest that action video game play may influence VWM as well. The current study utilized a training paradigm to examine whether action video games cause improvements to the quantity and/or the quality of information stored in VWM. The results suggest that VWM capacity, as measured by a change detection task, is increased after action video game training, as compared with training on a control game, and that some improvement to VWM precision occurs with action game training as well. However, these findings do not appear to extend to a complex span measure of VWM, which is often thought to tap into higher-order executive skills. The VWM improvements seen in individuals trained on an action video game cannot be accounted for by differences in motivation or engagement, differential expectations, or baseline differences in demographics as compared with the control group used. In sum, action video game training represents a potentially unique and engaging platform by which this severely capacity-limited VWM system might be enhanced.
2016-01-01
A novel method of extracting heart rate and oxygen saturation from a video-based biosignal is described. The method comprises a novel modular continuous wavelet transform approach which includes: performing the transform, undertaking running wavelet archetyping to enhance the pulse information, extraction of the pulse ridge time–frequency information [and thus a heart rate (HRvid) signal], creation of a wavelet ratio surface, projection of the pulse ridge onto the ratio surface to determine the ratio of ratios from which a saturation trending signal is derived, and calibrating this signal to provide an absolute saturation signal (SvidO2). The method is illustrated through its application to a video photoplethysmogram acquired during a porcine model of acute desaturation. The modular continuous wavelet transform-based approach is advocated by the author as a powerful methodology to deal with noisy, non-stationary biosignals in general. PMID:27382479
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henk, C.; Garner, J.; Wandersee, J.H.
1994-12-31
We acquired and loaned several durable, easy-to use, though expensive video-probe microscopes. This hand-held, automatically focusing instrument can be used by a five year old and provides instant, excellent, in-focus images up to 200X on a video screen visible to all students simultaneously. The teacher is thus freed from the technical and logistic considerations involved in conventional classroom microscopy. K-12 teachers preview our videotape on probe utilization. They assemble and demonstrate the unit in the presence of our personnel, then check out the probe for use in their own classrooms. Extremely enthusiastic students examine samples ranging from their own fingerprintsmore » and clothing (on TV!) to pond water, prepared microscope slides, and microscope polarizing light phenomena. Teachers report heightened interest in conventional microscope use once the {open_quotes}microscopy connection{close_quotes} has been made.« less
Stereo-Video Data Reduction of Wake Vortices and Trailing Aircrafts
NASA Technical Reports Server (NTRS)
Alter-Gartenberg, Rachel
1998-01-01
This report presents stereo image theory and the corresponding image processing software developed to analyze stereo imaging data acquired for the wake-vortex hazard flight experiment conducted at NASA Langley Research Center. In this experiment, a leading Lockheed C-130 was equipped with wing-tip smokers to visualize its wing vortices, while a trailing Boeing 737 flew into the wake vortices of the leading airplane. A Rockwell OV-10A airplane, fitted with video cameras under its wings, flew at 400 to 1000 feet above and parallel to the wakes, and photographed the wake interception process for the purpose of determining the three-dimensional location of the trailing aircraft relative to the wake. The report establishes the image-processing tools developed to analyze the video flight-test data, identifies sources of potential inaccuracies, and assesses the quality of the resultant set of stereo data reduction.
Cervinka, Miroslav; Cervinková, Zuzana; Novák, Jan; Spicák, Jan; Rudolf, Emil; Peychl, Jan
2004-06-01
Alternatives and their teaching are an essential part of the curricula at the Faculty of Medicine. Dynamic screen-based video recordings are the most important type of alternative models employed for teaching purposes. Currently, the majority of teaching materials for this purpose are based on PowerPoint presentations, which are very popular because of their high versatility and visual impact. Furthermore, current developments in the field of image capturing devices and software enable the use of digitised video streams, tailored precisely to the specific situation. Here, we demonstrate that with reasonable financial resources, it is possible to prepare video sequences and to introduce them into the PowerPoint presentation, thereby shaping the teaching process according to individual students' needs and specificities.
Weighted-MSE based on saliency map for assessing video quality of H.264 video streams
NASA Astrophysics Data System (ADS)
Boujut, H.; Benois-Pineau, J.; Hadar, O.; Ahmed, T.; Bonnet, P.
2011-01-01
Human vision system is very complex and has been studied for many years specifically for purposes of efficient encoding of visual, e.g. video content from digital TV. There have been physiological and psychological evidences which indicate that viewers do not pay equal attention to all exposed visual information, but only focus on certain areas known as focus of attention (FOA) or saliency regions. In this work, we propose a novel based objective quality assessment metric, for assessing the perceptual quality of decoded video sequences affected by transmission errors and packed loses. The proposed method weights the Mean Square Error (MSE), Weighted-MSE (WMSE), according to the calculated saliency map at each pixel. Our method was validated trough subjective quality experiments.
a Comparison Between Active and Passive Techniques for Underwater 3d Applications
NASA Astrophysics Data System (ADS)
Bianco, G.; Gallo, A.; Bruno, F.; Muzzupappa, M.
2011-09-01
In the field of 3D scanning, there is an increasing need for more accurate technologies to acquire 3D models of close range objects. Underwater exploration, for example, is very hard to perform due to the hostile conditions and the bad visibility of the environment. Some application fields, like underwater archaeology, require to recover tridimensional data of objects that cannot be moved from their site or touched in order to avoid possible damages. Photogrammetry is widely used for underwater 3D acquisition, because it requires just one or two digital still or video cameras to acquire a sequence of images taken from different viewpoints. Stereo systems composed by a pair of cameras are often employed on underwater robots (i.e. ROVs, Remotely Operated Vehicles) and used by scuba divers, in order to survey archaeological sites, reconstruct complex 3D structures in aquatic environment, estimate in situ the length of marine organisms, etc. The stereo 3D reconstruction is based on the triangulation of corresponding points on the two views. This requires to find in both images common points and to match them (correspondence problem), determining a plane that contains the 3D point on the object. Another 3D technique, frequently used in air acquisition, solves this point-matching problem by projecting structured lighting patterns to codify the acquired scene. The corresponding points are identified associating a binary code in both images. In this work we have tested and compared two whole-field 3D imaging techniques (active and passive) based on stereo vision, in underwater environment. A 3D system has been designed, composed by a digital projector and two still cameras mounted in waterproof housing, so that it can perform the various acquisitions without changing the configuration of optical devices. The tests were conducted in a water tank in different turbidity conditions, on objects with different surface properties. In order to simulate a typical seafloor, we used various concentrations of clay. The performances of the two techniques are described and discussed. In particular, the point clouds obtained are compared in terms of number of acquired 3D points and geometrical deviation.
Video Guidance Sensors Using Remotely Activated Targets
NASA Technical Reports Server (NTRS)
Bryan, Thomas C.; Howard, Richard T.; Book, Michael L.
2004-01-01
Four updated video guidance sensor (VGS) systems have been proposed. As described in a previous NASA Tech Briefs article, a VGS system is an optoelectronic system that provides guidance for automated docking of two vehicles. The VGS provides relative position and attitude (6-DOF) information between the VGS and its target. In the original intended application, the two vehicles would be spacecraft, but the basic principles of design and operation of the system are applicable to aircraft, robots, objects maneuvered by cranes, or other objects that may be required to be aligned and brought together automatically or under remote control. In the first two of the four VGS systems as now proposed, the tracked vehicle would include active targets that would light up on command from the tracking vehicle, and a video camera on the tracking vehicle would be synchronized with, and would acquire images of, the active targets. The video camera would also acquire background images during the periods between target illuminations. The images would be digitized and the background images would be subtracted from the illuminated-target images. Then the position and orientation of the tracked vehicle relative to the tracking vehicle would be computed from the known geometric relationships among the positions of the targets in the image, the positions of the targets relative to each other and to the rest of the tracked vehicle, and the position and orientation of the video camera relative to the rest of the tracking vehicle. The major difference between the first two proposed systems and prior active-target VGS systems lies in the techniques for synchronizing the flashing of the active targets with the digitization and processing of image data. In the prior active-target VGS systems, synchronization was effected, variously, by use of either a wire connection or the Global Positioning System (GPS). In three of the proposed VGS systems, the synchronizing signal would be generated on, and transmitted from, the tracking vehicle. In the first proposed VGS system, the tracking vehicle would transmit a pulse of light. Upon reception of the pulse, circuitry on the tracked vehicle would activate the target lights. During the pulse, the target image acquired by the camera would be digitized. When the pulse was turned off, the target lights would be turned off and the background video image would be digitized. The second proposed system would function similarly to the first proposed system, except that the transmitted synchronizing signal would be a radio pulse instead of a light pulse. In this system, the signal receptor would be a rectifying antenna. If the signal contained sufficient power, the output of the rectifying antenna could be used to activate the target lights, making it unnecessary to include a battery or other power supply for the targets on the tracked vehicle.
MPEG-4 ASP SoC receiver with novel image enhancement techniques for DAB networks
NASA Astrophysics Data System (ADS)
Barreto, D.; Quintana, A.; García, L.; Callicó, G. M.; Núñez, A.
2007-05-01
This paper presents a system for real-time video reception in low-power mobile devices using Digital Audio Broadcast (DAB) technology for transmission. A demo receiver terminal is designed into a FPGA platform using the Advanced Simple Profile (ASP) MPEG-4 standard for video decoding. In order to keep the demanding DAB requirements, the bandwidth of the encoded sequence must be drastically reduced. In this sense, prior to the MPEG-4 coding stage, a pre-processing stage is performed. It is firstly composed by a segmentation phase according to motion and texture based on the Principal Component Analysis (PCA) of the input video sequence, and secondly by a down-sampling phase, which depends on the segmentation results. As a result of the segmentation task, a set of texture and motion maps are obtained. These motion and texture maps are also included into the bit-stream as user data side-information and are therefore known to the receiver. For all bit-rates, the whole encoder/decoder system proposed in this paper exhibits higher image visual quality than the alternative encoding/decoding method, assuming equal image sizes. A complete analysis of both techniques has also been performed to provide the optimum motion and texture maps for the global system, which has been finally validated for a variety of video sequences. Additionally, an optimal HW/SW partition for the MPEG-4 decoder has been studied and implemented over a Programmable Logic Device with an embedded ARM9 processor. Simulation results show that a throughput of 15 QCIF frames per second can be achieved with low area and low power implementation.
Combining 3D structure of real video and synthetic objects
NASA Astrophysics Data System (ADS)
Kim, Man-Bae; Song, Mun-Sup; Kim, Do-Kyoon
1998-04-01
This paper presents a new approach of combining real video and synthetic objects. The purpose of this work is to use the proposed technology in the fields of advanced animation, virtual reality, games, and so forth. Computer graphics has been used in the fields previously mentioned. Recently, some applications have added real video to graphic scenes for the purpose of augmenting the realism that the computer graphics lacks in. This approach called augmented or mixed reality can produce more realistic environment that the entire use of computer graphics. Our approach differs from the virtual reality and augmented reality in the manner that computer- generated graphic objects are combined to 3D structure extracted from monocular image sequences. The extraction of the 3D structure requires the estimation of 3D depth followed by the construction of a height map. Graphic objects are then combined to the height map. The realization of our proposed approach is carried out in the following steps: (1) We derive 3D structure from test image sequences. The extraction of the 3D structure requires the estimation of depth and the construction of a height map. Due to the contents of the test sequence, the height map represents the 3D structure. (2) The height map is modeled by Delaunay triangulation or Bezier surface and each planar surface is texture-mapped. (3) Finally, graphic objects are combined to the height map. Because 3D structure of the height map is already known, Step (3) is easily manipulated. Following this procedure, we produced an animation video demonstrating the combination of the 3D structure and graphic models. Users can navigate the realistic 3D world whose associated image is rendered on the display monitor.
Besera, Ghenet T.; Cox, Shanna; Malotte, C. Kevin; Rietmeijer, Cornelis A.; Klausner, Jeffrey D.; O’Donnell, Lydia; Margolis, Andrew D.; Warner, Lee
2016-01-01
Safe in the City , a video intervention for clinic waiting rooms, was previously shown to reduce sexually transmitted disease (STD) incidence. However, little is known about patients’ recall of exposure to the intervention. Using data from a nested study of patients attending clinics during the trial, we assessed whether participants recalled Safe in the City, and, if so, how the intervention affected subsequent attitudes and behaviors. Analyses were restricted to responses to a 3-month follow-up questionnaire among participants who were exposed to the video (n = 708). Impact was measured as participants’ reports of the video’s effect on behaviors and attitudes. Associations were evaluated using multivariable logistic regression. Of participants who were exposed, 685 (97%) recalled viewing the video, and 68% recalled all three vignettes. After watching the video, participants felt more positive about condoms (69%) and comfortable acquiring condoms (56%), were reminded of important information about STDs and condoms (90%), and tried to apply what they learned to their lives (59%). Compared with those who recalled viewing one or two vignettes, participants who recalled viewing all three vignettes reported more positive attitudes toward condoms and peer/provider communication. These findings demonstrate that a low-resource video intervention for waiting rooms can provide sufficient exposure to positively influence STD-related attitudes/behaviors. PMID:27091608
Efficient stereoscopic contents file format on the basis of ISO base media file format
NASA Astrophysics Data System (ADS)
Kim, Kyuheon; Lee, Jangwon; Suh, Doug Young; Park, Gwang Hoon
2009-02-01
A lot of 3D contents haven been widely used for multimedia services, however, real 3D video contents have been adopted for a limited applications such as a specially designed 3D cinema. This is because of the difficulty of capturing real 3D video contents and the limitation of display devices available in a market. However, diverse types of display devices for stereoscopic video contents for real 3D video contents have been recently released in a market. Especially, a mobile phone with a stereoscopic camera has been released in a market, which provides a user as a consumer to have more realistic experiences without glasses, and also, as a content creator to take stereoscopic images or record the stereoscopic video contents. However, a user can only store and display these acquired stereoscopic contents with his/her own devices due to the non-existence of a common file format for these contents. This limitation causes a user not share his/her contents with any other users, which makes it difficult the relevant market to stereoscopic contents is getting expanded. Therefore, this paper proposes the common file format on the basis of ISO base media file format for stereoscopic contents, which enables users to store and exchange pure stereoscopic contents. This technology is also currently under development for an international standard of MPEG as being called as a stereoscopic video application format.
Senile myoclonic epilepsy in Down syndrome: a video and EEG presentation of two cases.
De Simone, Roberto; Daquin, Géraldine; Genton, Pierre
2006-09-01
Myoclonic epilepsy is being increasingly recognized as a late-onset complication in middle-aged or elderly patients with Down syndrome, in association with cognitive decline. We show video and EEG recordings of two patients, both aged 56 years, diagnosed with this condition. At onset, myoclonic epilepsy in elderly DS patients may resemble, in its clinical expression, the classical juvenile myoclonic epilepsy with the characteristic occurrence of jerks on awakening. It is clearly associated with an Alzheimer-type dementia, and may also occur in non-DS patients with Alzheimer's disease: hence the possible denomination of "senile myoclonic epilepsy". [Published with video sequences].
Logo recognition in video by line profile classification
NASA Astrophysics Data System (ADS)
den Hollander, Richard J. M.; Hanjalic, Alan
2003-12-01
We present an extension to earlier work on recognizing logos in video stills. The logo instances considered here are rigid planar objects observed at a distance in the scene, so the possible perspective transformation can be approximated by an affine transformation. For this reason we can classify the logos by matching (invariant) line profiles. We enhance our previous method by considering multiple line profiles instead of a single profile of the logo. The positions of the lines are based on maxima in the Hough transform space of the segmented logo foreground image. Experiments are performed on MPEG1 sport video sequences to show the performance of the proposed method.
Vector representation of user's view using self-organizing map
NASA Astrophysics Data System (ADS)
Ae, Tadashi; Yamaguchi, Tomohisa; Monden, Eri; Kawabata, Shunji; Kamitani, Motoki
2004-05-01
There exist various objects, such as pictures, music, texts, etc., around our environment. We have a view for these objects by looking, reading or listening. Our view is concerned with our behaviors deeply, and is very important to understand our behaviors. Therefore, we propose a method which acquires a view as a vector, and apply the vector to sequence generation. We focus on sequences of the data of which a user selects from a multimedia database containing pictures, music, movie, etc.. These data cannot be stereotyped because user's view for them changes by each user. Therefore, we represent the structure of the multimedia database as the vector representing user's view and the stereotyped vector, and acquire sequences containing the structure as elements. We demonstrate a city-sequence generation system which reflects user's intension as an application of sequence generation containing user's view. We apply the self-organizing map to this system to represent user's view.
Digital Watermarking: From Concepts to Real-Time Video Applications
1999-01-01
includes still- image , video, audio, and geometry data among others-the fundamental con- cept of steganography can be transferred from the field of...size of the message, which should be as small as possible. Some commercially available algorithms for image watermarking forego the secure-watermarking... image compres- sion.’ The image’s luminance component is divided into 8 x 8 pixel blocks. The algorithm selects a sequence of blocks and applies the
Test and Evaluation of Teleconferencing Video Codecs Transmitting at 1.5 Mbps.
1985-08-01
video teleconferencing codecs on the market as of November 1984 to facilitate the choice of an appropriate frame format and data compression algorithm...Engineer, computer company, male 5. Chapter Officer, national civic organization, female Group Y: 6. Marketing Representative, communication systems...both mon:tors to C4ve t e evi uators an idea what kind of cictures they will have to ; ucge . Special suggestions were given regardinc the sequences witn
Evaluation of MRI sequences for quantitative T1 brain mapping
NASA Astrophysics Data System (ADS)
Tsialios, P.; Thrippleton, M.; Glatz, A.; Pernet, C.
2017-11-01
T1 mapping constitutes a quantitative MRI technique finding significant application in brain imaging. It allows evaluation of contrast uptake, blood perfusion, volume, providing a more specific biomarker of disease progression compared to conventional T1-weighted images. While there are many techniques for T1-mapping there is a wide range of reported T1-values in tissues, raising the issue of protocols reproducibility and standardization. The gold standard for obtaining T1-maps is based on acquiring IR-SE sequence. Widely used alternative sequences are IR-SE-EPI, VFA (DESPOT), DESPOT-HIFI and MP2RAGE that speed up scanning and fitting procedures. A custom MRI phantom was used to assess the reproducibility and accuracy of the different methods. All scans were performed using a 3T Siemens Prisma scanner. The acquired data processed using two different codes. The main difference was observed for VFA (DESPOT) which grossly overestimated T1 relaxation time by 214 ms [126 270] compared to the IR-SE sequence. MP2RAGE and DESPOT-HIFI sequences gave slightly shorter time than IR-SE (~20 to 30ms) and can be considered as alternative and time-efficient methods for acquiring accurate T1 maps of the human brain, while IR-SE-EPI gave identical result, at a cost of a lower image quality.
NASA Astrophysics Data System (ADS)
Zhang, Dong Ping; Edwards, Eddie; Mei, Lin; Rueckert, Daniel
2009-02-01
In this paper, we present a novel approach for coronary artery motion modeling from cardiac Computed Tomography( CT) images. The aim of this work is to develop a 4D motion model of the coronaries for image guidance in robotic-assisted totally endoscopic coronary artery bypass (TECAB) surgery. To utilize the pre-operative cardiac images to guide the minimally invasive surgery, it is essential to have a 4D cardiac motion model to be registered with the stereo endoscopic images acquired intraoperatively using the da Vinci robotic system. In this paper, we are investigating the extraction of the coronary arteries and the modelling of their motion from a dynamic sequence of cardiac CT. We use a multi-scale vesselness filter to enhance vessels in the cardiac CT images. The centerlines of the arteries are extracted using a ridge traversal algorithm. Using this method the coronaries can be extracted in near real-time as only local information is used in vessel tracking. To compute the deformation of the coronaries due to cardiac motion, the motion is extracted from a dynamic sequence of cardiac CT. Each timeframe in this sequence is registered to the end-diastole timeframe of the sequence using a non-rigid registration algorithm based on free-form deformations. Once the images have been registered a dynamic motion model of the coronaries can be obtained by applying the computed free-form deformations to the extracted coronary arteries. To validate the accuracy of the motion model we compare the actual position of the coronaries in each time frame with the predicted position of the coronaries as estimated from the non-rigid registration. We expect that this motion model of coronaries can facilitate the planning of TECAB surgery, and through the registration with real-time endoscopic video images it can reduce the conversion rate from TECAB to conventional procedures.
NASA Astrophysics Data System (ADS)
Debon, Renaud; Le Guillou, Clara; Cauvin, Jean-Michel; Solaiman, Basel; Roux, Christian
2001-08-01
Medical domain makes intensive use of information fusion. In particular, the gastro-enterology is a discipline where physicians have the choice between several imagery modalities that offer complementary advantages. Among all existing systems, videoendoscopy (based on a CCD sensor) and echoendoscopy (based on an ultrasound sensor) are the most efficient. The use of each system corresponds to a given step in the physician diagnostic elaboration. Nowadays, several works aim to achieve automatic interpretation of videoendoscopic sequences. These systems can quantify color and superficial textures of the digestive tube. Unfortunately the relief information, which is important for the diagnostic, is very difficult to retrieve. On the other hand, some studies have proved that 3D information can be easily quantified using echoendoscopy image sequences. That is why the idea to combine these information, acquired from two very different points of view, can be considered as a real challenge for the medical image fusion topic. In this paper, after a review of actual works concerning numerical exploitation of videoendoscopy and echoendoscopy, the following question will be discussed: how can the use of complementary aspects of the different systems ease the automatic exploitation of videoendoscopy ? In a second time, we will evaluate the feasibility of the achievement of a realistic 3D reconstruction based both on information given by echoendoscopy (relief) and videoendoscopy (texture). Enumeration of potential applications of such a fusion system will then follow. Further discussions and perspectives will conclude this first study.
Adaptive metric learning with deep neural networks for video-based facial expression recognition
NASA Astrophysics Data System (ADS)
Liu, Xiaofeng; Ge, Yubin; Yang, Chao; Jia, Ping
2018-01-01
Video-based facial expression recognition has become increasingly important for plenty of applications in the real world. Despite that numerous efforts have been made for the single sequence, how to balance the complex distribution of intra- and interclass variations well between sequences has remained a great difficulty in this area. We propose the adaptive (N+M)-tuplet clusters loss function and optimize it with the softmax loss simultaneously in the training phrase. The variations introduced by personal attributes are alleviated using the similarity measurements of multiple samples in the feature space with many fewer comparison times as conventional deep metric learning approaches, which enables the metric calculations for large data applications (e.g., videos). Both the spatial and temporal relations are well explored by a unified framework that consists of an Inception-ResNet network with long short term memory and the two fully connected layer branches structure. Our proposed method has been evaluated with three well-known databases, and the experimental results show that our method outperforms many state-of-the-art approaches.
Tracking flow of leukocytes in blood for drug analysis
NASA Astrophysics Data System (ADS)
Basharat, Arslan; Turner, Wesley; Stephens, Gillian; Badillo, Benjamin; Lumpkin, Rick; Andre, Patrick; Perera, Amitha
2011-03-01
Modern microscopy techniques allow imaging of circulating blood components under vascular flow conditions. The resulting video sequences provide unique insights into the behavior of blood cells within the vasculature and can be used as a method to monitor and quantitate the recruitment of inflammatory cells at sites of vascular injury/ inflammation and potentially serve as a pharmacodynamic biomarker, helping screen new therapies and individualize dose and combinations of drugs. However, manual analysis of these video sequences is intractable, requiring hours per 400 second video clip. In this paper, we present an automated technique to analyze the behavior and recruitment of human leukocytes in whole blood under physiological conditions of shear through a simple multi-channel fluorescence microscope in real-time. This technique detects and tracks the recruitment of leukocytes to a bioactive surface coated on a flow chamber. Rolling cells (cells which partially bind to the bioactive matrix) are detected counted, and have their velocity measured and graphed. The challenges here include: high cell density, appearance similarity, and low (1Hz) frame rate. Our approach performs frame differencing based motion segmentation, track initialization and online tracking of individual leukocytes.
CRISPR-Cas systems exploit viral DNA injection to establish and maintain adaptive immunity.
Modell, Joshua W; Jiang, Wenyan; Marraffini, Luciano A
2017-04-06
Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems provide protection against viral and plasmid infection by capturing short DNA sequences from these invaders and integrating them into the CRISPR locus of the prokaryotic host. These sequences, known as spacers, are transcribed into short CRISPR RNA guides that specify the cleavage site of Cas nucleases in the genome of the invader. It is not known when spacer sequences are acquired during viral infection. Here, to investigate this, we tracked spacer acquisition in Staphylococcus aureus cells harbouring a type II CRISPR-Cas9 system after infection with the staphylococcal bacteriophage ϕ12. We found that new spacers were acquired immediately after infection preferentially from the cos site, the viral free DNA end that is first injected into the cell. Analysis of spacer acquisition after infection with mutant phages demonstrated that most spacers are acquired during DNA injection, but not during other stages of the viral cycle that produce free DNA ends, such as DNA replication or packaging. Finally, we showed that spacers acquired from early-injected genomic regions, which direct Cas9 cleavage of the viral DNA immediately after infection, provide better immunity than spacers acquired from late-injected regions. Our results reveal that CRISPR-Cas systems exploit the phage life cycle to generate a pattern of spacer acquisition that ensures a successful CRISPR immune response.
Dissecting children's observational learning of complex actions through selective video displays.
Flynn, Emma; Whiten, Andrew
2013-10-01
Children can learn how to use complex objects by watching others, yet the relative importance of different elements they may observe, such as the interactions of the individual parts of the apparatus, a model's movements, and desirable outcomes, remains unclear. In total, 140 3-year-olds and 140 5-year-olds participated in a study where they observed a video showing tools being used to extract a reward item from a complex puzzle box. Conditions varied according to the elements that could be seen in the video: (a) the whole display, including the model's hands, the tools, and the box; (b) the tools and the box but not the model's hands; (c) the model's hands and the tools but not the box; (d) only the end state with the box opened; and (e) no demonstration. Children's later attempts at the task were coded to establish whether they imitated the hierarchically organized sequence of the model's actions, the action details, and/or the outcome. Children's successful retrieval of the reward from the box and the replication of hierarchical sequence information were reduced in all but the whole display condition. Only once children had attempted the task and witnessed a second demonstration did the display focused on the tools and box prove to be better for hierarchical sequence information than the display focused on the tools and hands only. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Bonanno, A.; Bozzo, G.; Sapia, P.
2017-11-01
In this work, we present a coherent sequence of experiments on electromagnetic (EM) induction and eddy currents, appropriate for university undergraduate students, based on a magnet falling through a drilled aluminum disk. The sequence, leveraging on the didactical interplay between the EM and mechanical aspects of the experiments, allows us to exploit the students’ awareness of mechanics to elicit their comprehension of EM phenomena. The proposed experiments feature two kinds of measurements: (i) kinematic measurements (performed by means of high-speed video analysis) give information on the system’s kinematics and, via appropriate numerical data processing, allow us to get dynamic information, in particular on energy dissipation; (ii) induced electromagnetic field (EMF) measurements (by using a homemade multi-coil sensor connected to a cheap data acquisition system) allow us to quantitatively determine the inductive effects of the moving magnet on its neighborhood. The comparison between experimental results and the predictions from an appropriate theoretical model (of the dissipative coupling between the moving magnet and the conducting disk) offers many educational hints on relevant topics related to EM induction, such as Maxwell’s displacement current, magnetic field flux variation, and the conceptual link between induced EMF and induced currents. Moreover, the didactical activity gives students the opportunity to be trained in video analysis, data acquisition and numerical data processing.
Space Shuttle Main Engine Propellant Path Leak Detection Using Sequential Image Processing
NASA Technical Reports Server (NTRS)
Smith, L. Montgomery; Malone, Jo Anne; Crawford, Roger A.
1995-01-01
Initial research in this study using theoretical radiation transport models established that the occurrence of a leak is accompanies by a sudden but sustained change in intensity in a given region of an image. In this phase, temporal processing of video images on a frame-by-frame basis was used to detect leaks within a given field of view. The leak detection algorithm developed in this study consists of a digital highpass filter cascaded with a moving average filter. The absolute value of the resulting discrete sequence is then taken and compared to a threshold value to produce the binary leak/no leak decision at each point in the image. Alternatively, averaging over the full frame of the output image produces a single time-varying mean value estimate that is indicative of the intensity and extent of a leak. Laboratory experiments were conducted in which artificially created leaks on a simulated SSME background were produced and recorded from a visible wavelength video camera. This data was processed frame-by-frame over the time interval of interest using an image processor implementation of the leak detection algorithm. In addition, a 20 second video sequence of an actual SSME failure was analyzed using this technique. The resulting output image sequences and plots of the full frame mean value versus time verify the effectiveness of the system.
Khanduja, Sumeet; Sampangi, Raju; Hemlatha, B C; Singh, Satvir; Lall, Ashish
2018-01-01
Purpose: The purpose of this study is to describe the use of commercial digital single light reflex (DSLR) for vitreoretinal surgery recording and compare it to standard 3-chip charged coupling device (CCD) camera. Methods: Simultaneous recording was done using Sony A7s2 camera and Sony high-definition 3-chip camera attached to each side of the microscope. The videos recorded from both the camera systems were edited and sequences of similar time frames were selected. Three sequences that selected for evaluation were (a) anterior segment surgery, (b) surgery under direct viewing system, and (c) surgery under indirect wide-angle viewing system. The videos of each sequence were evaluated and rated on a scale of 0-10 for color, contrast, and overall quality Results: Most results were rated either 8/10 or 9/10 for both the cameras. A noninferiority analysis by comparing mean scores of DSLR camera versus CCD camera was performed and P values were obtained. The mean scores of the two cameras were comparable for each other on all parameters assessed in the different videos except of color and contrast in posterior pole view and color on wide-angle view, which were rated significantly higher (better) in DSLR camera. Conclusion: Commercial DSLRs are an affordable low-cost alternative for vitreoretinal surgery recording and may be used for documentation and teaching. PMID:29283133
Khanduja, Sumeet; Sampangi, Raju; Hemlatha, B C; Singh, Satvir; Lall, Ashish
2018-01-01
The purpose of this study is to describe the use of commercial digital single light reflex (DSLR) for vitreoretinal surgery recording and compare it to standard 3-chip charged coupling device (CCD) camera. Simultaneous recording was done using Sony A7s2 camera and Sony high-definition 3-chip camera attached to each side of the microscope. The videos recorded from both the camera systems were edited and sequences of similar time frames were selected. Three sequences that selected for evaluation were (a) anterior segment surgery, (b) surgery under direct viewing system, and (c) surgery under indirect wide-angle viewing system. The videos of each sequence were evaluated and rated on a scale of 0-10 for color, contrast, and overall quality Results: Most results were rated either 8/10 or 9/10 for both the cameras. A noninferiority analysis by comparing mean scores of DSLR camera versus CCD camera was performed and P values were obtained. The mean scores of the two cameras were comparable for each other on all parameters assessed in the different videos except of color and contrast in posterior pole view and color on wide-angle view, which were rated significantly higher (better) in DSLR camera. Commercial DSLRs are an affordable low-cost alternative for vitreoretinal surgery recording and may be used for documentation and teaching.
Low-Latency Telerobotic Sample Return and Biomolecular Sequencing for Deep Space Gateway
NASA Astrophysics Data System (ADS)
Lupisella, M.; Bleacher, J.; Lewis, R.; Dworkin, J.; Wright, M.; Burton, A.; Rubins, K.; Wallace, S.; Stahl, S.; John, K.; Archer, D.; Niles, P.; Regberg, A.; Smith, D.; Race, M.; Chiu, C.; Russell, J.; Rampe, E.; Bywaters, K.
2018-02-01
Low-latency telerobotics, crew-assisted sample return, and biomolecular sequencing can be used to acquire and analyze lunar farside and/or Apollo landing site samples. Sequencing can also be used to monitor and study Deep Space Gateway environment and crew health.
Côrtes, Marina Farrel; Costa, Maiana OC; Lima, Nicholas CB; Souza, Rangel C; Almeida, Luiz GP; Guedes, Luciane Prioli Ciapina; Vasconcelos, Ana TR; Nicolás, Marisa F; Figueiredo, Agnes MS
2017-01-01
Staphylococcus aureus subsp. aureus, commonly referred as S. aureus, is an important bacterial pathogen frequently involved in hospital- and community-acquired infections in humans, ranging from skin infections to more severe diseases such as pneumonia, bacteraemia, endocarditis, osteomyelitis, and disseminated infections. Here, we report the complete closed genome sequence of a community-acquired methicillin-resistant S. aureus strain, USA400-0051, which is a prototype of the USA400 clone. PMID:29091141
Development and Testing of Harpoon-Based Approaches for Collecting Comet Samples (Video Supplement)
NASA Technical Reports Server (NTRS)
Purves, Lloyd (Compiler); Nuth, Joseph (Compiler); Amatucci, Edward (Compiler); Wegel, Donald; Smith, Walter; Leary, James; Kee, Lake; Hill, Stuart; Grebenstein, Markus; Voelk, Stefan;
2017-01-01
This video supplement contains a set of videos created during the approximately 10-year-long course of developing and testing the Goddard Space Flight Center (GSFC) harpoon-based approach for collecting comet samples. The purpose of the videos is to illustrate various design concepts used in this method of acquiring samples of comet material, the testing used to verify the concepts, and the evolution of designs and testing. To play the videos this PDF needs to be opened in the freeware Adobe Reader. They do not seem to play while within a browser. While this supplement can be used as a stand-alone document, it is intended to augment its parent document of the same title, Development and Testing of Harpoon-Based Approaches for Collecting Comet Samples (NASA/CR-2017-219018; this document is accessible from the website: https://ssed.gsfc.nasa.gov/harpoon/SAS_Paper-V1.pdf). The parent document, which only contains text and figures, describes the overall development and testing effort and contains references to each of the videos in this supplement. Thus, the videos are primarily intended to augment the information provided by the text and figures in the parent document. This approach was followed to allow the file size of the parent document to remain small enough to facilitate downloading and storage. Some of the videos were created by other organizations, Johns Hopkins University Applied Physics Laboratory (JHU APL) and the German Aerospace Center called, the Deutsches Zentrum für Luft- und Raumfahrt (DLR), who are partnering with GSFC on developing this technology. Each video is accompanied by text that provides a summary description of its nature and purpose, as well as the identity of the authors. All videos have been edited to only show key parts of the testing. Although not all videos have sound, the sound has been retained in those that have it. Also, each video has been given one or more title screens to clarify what is going in different phases of the video.
Are YouTube videos accurate and reliable on basic life support and cardiopulmonary resuscitation?
Yaylaci, Serpil; Serinken, Mustafa; Eken, Cenker; Karcioglu, Ozgur; Yilmaz, Atakan; Elicabuk, Hayri; Dal, Onur
2014-10-01
The objective of this study is to investigate reliability and accuracy of the information on YouTube videos related to CPR and BLS in accord with 2010 CPR guidelines. YouTube was queried using four search terms 'CPR', 'cardiopulmonary resuscitation', 'BLS' and 'basic life support' between 2011 and 2013. Sources that uploaded the videos, the record time, the number of viewers in the study period, inclusion of human or manikins were recorded. The videos were rated if they displayed the correct order of resuscitative efforts in full accord with 2010 CPR guidelines or not. Two hundred and nine videos meeting the inclusion criteria after the search in YouTube with four search terms ('CPR', 'cardiopulmonary resuscitation', 'BLS' and 'basic life support') comprised the study sample subjected to the analysis. Median score of the videos is 5 (IQR: 3.5-6). Only 11.5% (n = 24) of the videos were found to be compatible with 2010 CPR guidelines with regard to sequence of interventions. Videos uploaded by 'Guideline bodies' had significantly higher rates of download when compared with the videos uploaded by other sources. Sources of the videos and date of upload (year) were not shown to have any significant effect on the scores received (P = 0.615 and 0.513, respectively). The videos' number of downloads did not differ according to the videos compatible with the guidelines (P = 0.832). The videos downloaded more than 10,000 times had a higher score than the others (P = 0.001). The majority of You-Tube video clips purporting to be about CPR are not relevant educational material. Of those that are focused on teaching CPR, only a small minority optimally meet the 2010 Resucitation Guidelines. © 2014 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.
1999-12-01
was operated over a network of four distributed clients connected to a Windows NT 4.0 server. The CU- SeeMe software was selected over University of...Acquires From Cornell University Full Intellectual Property Ownership Rights to CU- SeeMe and MeetingPoint Technologies, http://www.wpine.com
ERIC Educational Resources Information Center
Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.
The Environmental Quality Instructional Resources Center acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. This publication contains abstracts and indexes to selected materials related…
Advancing Development of Intercultural Competence through Supporting Predictions in Narrative Video
ERIC Educational Resources Information Center
Ogan, Amy; Aleven, Vincent; Jones, Christopher
2009-01-01
Most successes in intelligent tutoring systems have come in well-defined domains like algebra or physics. We investigate how to support students in acquiring ill-defined skills of intercultural competence using an online environment that employs clips of feature films from a target culture. To test the effectiveness of a set of attention-focusing…
ERIC Educational Resources Information Center
Cullen, Jennifer M.; Simmons-Reed, Evette A.; Weaver, Lindy
2017-01-01
Barriers in acquiring, maintaining, and generalizing daily living skills are factors that contribute to discrepancies in independent living outcomes among transition age youth and young adults with intellectual and developmental disabilities (IDD). Acquisition and generalization of daily living skills empowers transition age youth and young adults…
Children's Acquisition of Science Terms: Simple Exposure Is Insufficient
ERIC Educational Resources Information Center
Dockrell, Julie E.; Braisby, Nick; Best, Rachel M.
2007-01-01
The ability of school children (N = 233) to acquire new scientific vocabulary was examined. Children from two age groups (M = 4.8 and M = 6.5) were introduced to previously unknown words in an educational video. Word knowledge was assessed through accuracy and latency for production and comprehension over a 9-month period. A draw and write task…
Lights, Camera, AG-Tion: Promoting Agricultural and Environmental Education on Camera
ERIC Educational Resources Information Center
Fuhrman, Nicholas E.
2016-01-01
Viewing of online videos and television segments has become a popular and efficient way for Extension audiences to acquire information. This article describes a unique approach to teaching on camera that may help Extension educators communicate their messages with comfort and personality. The S.A.L.A.D. approach emphasizes using relevant teaching…
Using Online Videos to Improve Speaking Abilities of EFL Learners
ERIC Educational Resources Information Center
Yükselir, Ceyhun; Kömür, Sevki
2017-01-01
There is a growing tendency among the researchers about how to assess and improve the ability of speaking. In spite of its complex nature, speaking is generally considered to be the most essential skill to acquire. With the onset of communicative language teaching, this inclination has encouraged researchers to carry out research and make…
ERIC Educational Resources Information Center
Fischer, Sheryl L.; Walker, April L.
This booklet outlines a comprehensive fire and burn injury prevention program which includes an instructor's manual, a videotape, and a test: the video provides additional information and examples of injury prevention techniques, and the test measures the amount of knowledge acquired. Following an introduction, the prevalence and extent of burn…
ERIC Educational Resources Information Center
Ko, Chao-Jung
2012-01-01
This study investigated the possibility that initial-level learners may acquire oral skills through synchronous computer-mediated communication (SCMC). Twelve Taiwanese French as a foreign language (FFL) students, divided into three groups, were required to conduct a variety of tasks in one of the three learning environments (video/audio, audio,…
NASA Astrophysics Data System (ADS)
Davies, Bob; Lienhart, Rainer W.; Yeo, Boon-Lock
1999-08-01
The metaphor of film and TV permeates the design of software to support video on the PC. Simply transplanting the non- interactive, sequential experience of film to the PC fails to exploit the virtues of the new context. Video ont eh PC should be interactive and non-sequential. This paper experiments with a variety of tools for using video on the PC that exploits the new content of the PC. Some feature are more successful than others. Applications that use these tools are explored, including primarily the home video archive but also streaming video servers on the Internet. The ability to browse, edit, abstract and index large volumes of video content such as home video and corporate video is a problem without appropriate solution in today's market. The current tools available are complex, unfriendly video editors, requiring hours of work to prepare a short home video, far more work that a typical home user can be expected to provide. Our proposed solution treats video like a text document, providing functionality similar to a text editor. Users can browse, interact, edit and compose one or more video sequences with the same ease and convenience as handling text documents. With this level of text-like composition, we call what is normally a sequential medium a 'video document'. An important component of the proposed solution is shot detection, the ability to detect when a short started or stopped. When combined with a spreadsheet of key frames, the host become a grid of pictures that can be manipulated and viewed in the same way that a spreadsheet can be edited. Multiple video documents may be viewed, joined, manipulated, and seamlessly played back. Abstracts of unedited video content can be produce automatically to create novel video content for export to other venues. Edited and raw video content can be published to the net or burned to a CD-ROM with a self-installing viewer for Windows 98 and Windows NT 4.0.
Design of a highly integrated video acquisition module for smart video flight unit development
NASA Astrophysics Data System (ADS)
Lebre, V.; Gasti, W.
2017-11-01
CCD and APS devices are widely used in space missions as instrument sensors and/or in Avionics units like star detectors/trackers. Therefore, various and numerous designs of video acquisition chains have been produced. Basically, a classical video acquisition chain is constituted of two main functional blocks: the Proximity Electronics (PEC), including detector drivers and the Analogue Processing Chain (APC) Electronics that embeds the ADC, a master sequencer and the host interface. Nowadays, low power technologies allow to improve the integration, radiometric performances and power budget optimisation of video units and to standardize video units design and development. To this end, ESA has initiated a development activity through a competitive process requesting the expertise of experienced actors in the field of high resolution electronics for earth observation and Scientific missions. THALES ALENIA SPACE has been granted this activity as a prime contractor through ESA contract called HIVAC that holds for Highly Integrated Video Acquisition Chain. This paper presents main objectives of the on going HIVAC project and focuses on the functionalities and performances offered by the usage of the under development HIVAC board for future optical instruments.
Kalwitzki, M; Beyer, C; Meller, C
2010-11-01
Whilst preparing undergraduate students for a clinical course in paediatric dentistry, four consecutive classes (n = 107) were divided into two groups. Seven behaviour-modifying techniques were introduced: systematic desensitization, operant conditioning, modelling, Tell, Show, Do-principle, substitution, change of roles and the active involvement of the patient. The behaviour-modifying techniques that had been taught to group one (n = 57) through lecturing were taught to group two (n = 50) through video sequences and vice versa in the following semester. Immediately after the presentations, students were asked by means of a questionnaire about their perceptions of ease of using the different techniques and their intention for clinical application of each technique. After completion of the clinical course, they were asked about which behaviour-modifying techniques they had actually used when dealing with patients. Concerning the perception of ease of using the different techniques, there were considerable differences for six of the seven techniques (P < 0.05). Whilst some techniques seemed more difficult to apply clinically after lecturing, others seemed more difficult after video-based teaching. Concerning the intention for clinical application and the actual clinical application, there were higher percentages for all techniques taught after video-based teaching. However, the differences were significant only for two techniques in each case (P < 0.05). It is concluded that the use of video based teaching enhances the intention for application and the actual clinical application only for a limited number of behaviour-modifying techniques. © 2010 John Wiley & Sons A/S.
Bimodal emotion congruency is critical to preverbal infants' abstract rule learning.
Tsui, Angeline Sin Mei; Ma, Yuen Ki; Ho, Anna; Chow, Hiu Mei; Tseng, Chia-huei
2016-05-01
Extracting general rules from specific examples is important, as we must face the same challenge displayed in various formats. Previous studies have found that bimodal presentation of grammar-like rules (e.g. ABA) enhanced 5-month-olds' capacity to acquire a rule that infants failed to learn when the rule was presented with visual presentation of the shapes alone (circle-triangle-circle) or auditory presentation of the syllables (la-ba-la) alone. However, the mechanisms and constraints for this bimodal learning facilitation are still unknown. In this study, we used audio-visual relation congruency between bimodal stimulation to disentangle possible facilitation sources. We exposed 8- to 10-month-old infants to an AAB sequence consisting of visual faces with affective expressions and/or auditory voices conveying emotions. Our results showed that infants were able to distinguish the learned AAB rule from other novel rules under bimodal stimulation when the affects in audio and visual stimuli were congruently paired (Experiments 1A and 2A). Infants failed to acquire the same rule when audio-visual stimuli were incongruently matched (Experiment 2B) and when only the visual (Experiment 1B) or the audio (Experiment 1C) stimuli were presented. Our results highlight that bimodal facilitation in infant rule learning is not only dependent on better statistical probability and redundant sensory information, but also the relational congruency of audio-visual information. A video abstract of this article can be viewed at https://m.youtube.com/watch?v=KYTyjH1k9RQ. © 2015 John Wiley & Sons Ltd.
Sekiya, Taki; Miwa, Zenzo; Tsuchihashi, Natsumi; Uehara, Naoko; Sugimoto, Kumiko
2015-03-30
Since the understanding of emotional changes induced by dental treatments is important for dentists to provide a safe and comfortable dental treatment, we analyzed physiological responses during watching video images of dental treatments to search for the appropriate objective indices reflecting emotional changes. Fifteen healthy young adult subjects voluntarily participated in the present study. Electrocardiogram (ECG), electroencephalogram (EEG) and corrugator muscle electromyogram (EMG) were recorded and changes of them by viewing videos of dental treatments were analyzed. The subjective discomfort level was acquired by Visual Analog Scale method. Analyses of autonomic nervous activities from ECG and four emotional factors (anger/stress, joy/satisfaction, sadness/depression and relaxation) from EEG demonstrated that increases in sympathetic nervous activity reflecting stress increase and decreases in relaxation level were induced by the videos of infiltration anesthesia and cavity excavation, but not intraoral examination. The corrugator muscle activity was increased by all three images regardless of video contents. The subjective discomfort during watching infiltration anesthesia and cavity excavation was higher than intraoral examination, showing that sympathetic activities and relaxation factor of emotion changed in a manner consistent with subjective emotional changes. These results suggest that measurement of autonomic nervous activities estimated from ECG and emotional factors analyzed from EEG is useful for objective evaluation of subjective emotion.
Bähr, Florian; Ritter, Alexander; Seidel, Gundula; Puta, Christian; Gabriel, Holger H W; Hamzei, Farsin
2018-01-01
Action observation (AO) allows access to a network that processes visuomotor and sensorimotor inputs and is believed to be involved in observational learning of motor skills. We conducted three consecutive experiments to examine the boosting effect of AO on the motor outcome of the untrained hand by either mirror visual feedback (MVF), video therapy (VT), or a combination of both. In the first experiment, healthy participants trained either with MVF or without mirror feedback while in the second experiment, participants either trained with VT or observed animal videos. In the third experiment, participants first observed video clips that were followed by either training with MVF or training without mirror feedback. The outcomes for the untrained hand were quantified by scores from five motor tasks. The results demonstrated that MVF and VT significantly increase the motor performance of the untrained hand by the use of AO. We found that MVF was the most effective approach to increase the performance of the target effector. On the contrary, the combination of MVF and VT turns out to be less effective looking from clinical perspective. The gathered results suggest that action-related motor competence with the untrained hand is acquired by both mirror-based and video-based AO.
Ritter, Alexander; Seidel, Gundula; Puta, Christian; Gabriel, Holger H. W.; Hamzei, Farsin
2018-01-01
Action observation (AO) allows access to a network that processes visuomotor and sensorimotor inputs and is believed to be involved in observational learning of motor skills. We conducted three consecutive experiments to examine the boosting effect of AO on the motor outcome of the untrained hand by either mirror visual feedback (MVF), video therapy (VT), or a combination of both. In the first experiment, healthy participants trained either with MVF or without mirror feedback while in the second experiment, participants either trained with VT or observed animal videos. In the third experiment, participants first observed video clips that were followed by either training with MVF or training without mirror feedback. The outcomes for the untrained hand were quantified by scores from five motor tasks. The results demonstrated that MVF and VT significantly increase the motor performance of the untrained hand by the use of AO. We found that MVF was the most effective approach to increase the performance of the target effector. On the contrary, the combination of MVF and VT turns out to be less effective looking from clinical perspective. The gathered results suggest that action-related motor competence with the untrained hand is acquired by both mirror-based and video-based AO. PMID:29849570
Subjective Quality Assessment of Underwater Video for Scientific Applications
Moreno-Roldán, José-Miguel; Luque-Nieto, Miguel-Ángel; Poncela, Javier; Díaz-del-Río, Víctor; Otero, Pablo
2015-01-01
Underwater video services could be a key application in the better scientific knowledge of the vast oceanic resources in our planet. However, limitations in the capacity of current available technology for underwater networks (UWSNs) raise the question of the feasibility of these services. When transmitting video, the main constraints are the limited bandwidth and the high propagation delays. At the same time the service performance depends on the needs of the target group. This paper considers the problems of estimations for the Mean Opinion Score (a standard quality measure) in UWSNs based on objective methods and addresses the topic of quality assessment in potential underwater video services from a subjective point of view. The experimental design and the results of a test planned according standardized psychometric methods are presented. The subjects used in the quality assessment test were ocean scientists. Video sequences were recorded in actual exploration expeditions and were processed to simulate conditions similar to those that might be found in UWSNs. Our experimental results show how videos are considered to be useful for scientific purposes even in very low bitrate conditions. PMID:26694400
A semi-automatic annotation tool for cooking video
NASA Astrophysics Data System (ADS)
Bianco, Simone; Ciocca, Gianluigi; Napoletano, Paolo; Schettini, Raimondo; Margherita, Roberto; Marini, Gianluca; Gianforme, Giorgio; Pantaleo, Giuseppe
2013-03-01
In order to create a cooking assistant application to guide the users in the preparation of the dishes relevant to their profile diets and food preferences, it is necessary to accurately annotate the video recipes, identifying and tracking the foods of the cook. These videos present particular annotation challenges such as frequent occlusions, food appearance changes, etc. Manually annotate the videos is a time-consuming, tedious and error-prone task. Fully automatic tools that integrate computer vision algorithms to extract and identify the elements of interest are not error free, and false positive and false negative detections need to be corrected in a post-processing stage. We present an interactive, semi-automatic tool for the annotation of cooking videos that integrates computer vision techniques under the supervision of the user. The annotation accuracy is increased with respect to completely automatic tools and the human effort is reduced with respect to completely manual ones. The performance and usability of the proposed tool are evaluated on the basis of the time and effort required to annotate the same video sequences.
Strategies for combining physics videos and virtual laboratories in the training of physics teachers
NASA Astrophysics Data System (ADS)
Dickman, Adriana; Vertchenko, Lev; Martins, Maria Inés
2007-03-01
Among the multimedia resources used in physics education, the most prominent are virtual laboratories and videos. On one hand, computer simulations and applets have very attractive graphic interfaces, showing an incredible amount of detail and movement. On the other hand, videos, offer the possibility of displaying high quality images, and are becoming more feasible with the increasing availability of digital resources. We believe it is important to discuss, throughout the teacher training program, both the functionality of information and communication technology (ICT) in physics education and, the varied applications of these resources. In our work we suggest the introduction of ICT resources in a sequence integrating these important tools in the teacher training program, as opposed to the traditional approach, in which virtual laboratories and videos are introduced separately. In this perspective, when we introduce and utilize virtual laboratory techniques we also provide for its use in videos, taking advantage of graphic interfaces. Thus the students in our program learn to use instructional software in the production of videos for classroom use.
Subjective Quality Assessment of Underwater Video for Scientific Applications.
Moreno-Roldán, José-Miguel; Luque-Nieto, Miguel-Ángel; Poncela, Javier; Díaz-del-Río, Víctor; Otero, Pablo
2015-12-15
Underwater video services could be a key application in the better scientific knowledge of the vast oceanic resources in our planet. However, limitations in the capacity of current available technology for underwater networks (UWSNs) raise the question of the feasibility of these services. When transmitting video, the main constraints are the limited bandwidth and the high propagation delays. At the same time the service performance depends on the needs of the target group. This paper considers the problems of estimations for the Mean Opinion Score (a standard quality measure) in UWSNs based on objective methods and addresses the topic of quality assessment in potential underwater video services from a subjective point of view. The experimental design and the results of a test planned according standardized psychometric methods are presented. The subjects used in the quality assessment test were ocean scientists. Video sequences were recorded in actual exploration expeditions and were processed to simulate conditions similar to those that might be found in UWSNs. Our experimental results show how videos are considered to be useful for scientific purposes even in very low bitrate conditions.
Detection of goal events in soccer videos
NASA Astrophysics Data System (ADS)
Kim, Hyoung-Gook; Roeber, Steffen; Samour, Amjad; Sikora, Thomas
2005-01-01
In this paper, we present an automatic extraction of goal events in soccer videos by using audio track features alone without relying on expensive-to-compute video track features. The extracted goal events can be used for high-level indexing and selective browsing of soccer videos. The detection of soccer video highlights using audio contents comprises three steps: 1) extraction of audio features from a video sequence, 2) event candidate detection of highlight events based on the information provided by the feature extraction Methods and the Hidden Markov Model (HMM), 3) goal event selection to finally determine the video intervals to be included in the summary. For this purpose we compared the performance of the well known Mel-scale Frequency Cepstral Coefficients (MFCC) feature extraction method vs. MPEG-7 Audio Spectrum Projection feature (ASP) extraction method based on three different decomposition methods namely Principal Component Analysis( PCA), Independent Component Analysis (ICA) and Non-Negative Matrix Factorization (NMF). To evaluate our system we collected five soccer game videos from various sources. In total we have seven hours of soccer games consisting of eight gigabytes of data. One of five soccer games is used as the training data (e.g., announcers' excited speech, audience ambient speech noise, audience clapping, environmental sounds). Our goal event detection results are encouraging.
An Attention-Information-Based Spatial Adaptation Framework for Browsing Videos via Mobile Devices
NASA Astrophysics Data System (ADS)
Li, Houqiang; Wang, Yi; Chen, Chang Wen
2007-12-01
With the growing popularity of personal digital assistant devices and smart phones, more and more consumers are becoming quite enthusiastic to appreciate videos via mobile devices. However, limited display size of the mobile devices has been imposing significant barriers for users to enjoy browsing high-resolution videos. In this paper, we present an attention-information-based spatial adaptation framework to address this problem. The whole framework includes two major parts: video content generation and video adaptation system. During video compression, the attention information in video sequences will be detected using an attention model and embedded into bitstreams with proposed supplement-enhanced information (SEI) structure. Furthermore, we also develop an innovative scheme to adaptively adjust quantization parameters in order to simultaneously improve the quality of overall encoding and the quality of transcoding the attention areas. When the high-resolution bitstream is transmitted to mobile users, a fast transcoding algorithm we developed earlier will be applied to generate a new bitstream for attention areas in frames. The new low-resolution bitstream containing mostly attention information, instead of the high-resolution one, will be sent to users for display on the mobile devices. Experimental results show that the proposed spatial adaptation scheme is able to improve both subjective and objective video qualities.
Bayesian Modeling of Temporal Coherence in Videos for Entity Discovery and Summarization.
Mitra, Adway; Biswas, Soma; Bhattacharyya, Chiranjib
2017-03-01
A video is understood by users in terms of entities present in it. Entity Discovery is the task of building appearance model for each entity (e.g., a person), and finding all its occurrences in the video. We represent a video as a sequence of tracklets, each spanning 10-20 frames, and associated with one entity. We pose Entity Discovery as tracklet clustering, and approach it by leveraging Temporal Coherence (TC): the property that temporally neighboring tracklets are likely to be associated with the same entity. Our major contributions are the first Bayesian nonparametric models for TC at tracklet-level. We extend Chinese Restaurant Process (CRP) to TC-CRP, and further to Temporally Coherent Chinese Restaurant Franchise (TC-CRF) to jointly model entities and temporal segments using mixture components and sparse distributions. For discovering persons in TV serial videos without meta-data like scripts, these methods show considerable improvement over state-of-the-art approaches to tracklet clustering in terms of clustering accuracy, cluster purity and entity coverage. The proposed methods can perform online tracklet clustering on streaming videos unlike existing approaches, and can automatically reject false tracklets. Finally we discuss entity-driven video summarization- where temporal segments of the video are selected based on the discovered entities, to create a semantically meaningful summary.
Video transmission on ATM networks. Ph.D. Thesis
NASA Technical Reports Server (NTRS)
Chen, Yun-Chung
1993-01-01
The broadband integrated services digital network (B-ISDN) is expected to provide high-speed and flexible multimedia applications. Multimedia includes data, graphics, image, voice, and video. Asynchronous transfer mode (ATM) is the adopted transport techniques for B-ISDN and has the potential for providing a more efficient and integrated environment for multimedia. It is believed that most broadband applications will make heavy use of visual information. The prospect of wide spread use of image and video communication has led to interest in coding algorithms for reducing bandwidth requirements and improving image quality. The major results of a study on the bridging of network transmission performance and video coding are: Using two representative video sequences, several video source models are developed. The fitness of these models are validated through the use of statistical tests and network queuing performance. A dual leaky bucket algorithm is proposed as an effective network policing function. The concept of the dual leaky bucket algorithm can be applied to a prioritized coding approach to achieve transmission efficiency. A mapping of the performance/control parameters at the network level into equivalent parameters at the video coding level is developed. Based on that, a complete set of principles for the design of video codecs for network transmission is proposed.
A polygon soup representation for free viewpoint video
NASA Astrophysics Data System (ADS)
Colleu, T.; Pateux, S.; Morin, L.; Labit, C.
2010-02-01
This paper presents a polygon soup representation for multiview data. Starting from a sequence of multi-view video plus depth (MVD) data, the proposed representation takes into account, in a unified manner, different issues such as compactness, compression, and intermediate view synthesis. The representation is built in two steps. First, a set of 3D quads is extracted using a quadtree decomposition of the depth maps. Second, a selective elimination of the quads is performed in order to reduce inter-view redundancies and thus provide a compact representation. Moreover, the proposed methodology for extracting the representation allows to reduce ghosting artifacts. Finally, an adapted compression technique is proposed that limits coding artifacts. The results presented on two real sequences show that the proposed representation provides a good trade-off between rendering quality and data compactness.
NASA Technical Reports Server (NTRS)
Scharf, R.
2014-01-01
The ISS External Survey integrates the requirements for photographic and video imagery of the International Space Station (ISS) for the engineering, operations, and science communities. An extensive photographic survey was performed on all Space Shuttle flights to the ISS and continues to be performed daily, though on a level much reduced by the limited available imagery. The acquired video and photo imagery is used for both qualitative and quantitative assessments of external deposition and contamination, surface degradation, dynamic events, and MMOD strikes. Many of these assessments provide important information about ISS surfaces and structural integrity as the ISS ages. The imagery is also used to assess and verify the physical configuration of ISS structure, appendages, and components.
Automatic Mrf-Based Registration of High Resolution Satellite Video Data
NASA Astrophysics Data System (ADS)
Platias, C.; Vakalopoulou, M.; Karantzalos, K.
2016-06-01
In this paper we propose a deformable registration framework for high resolution satellite video data able to automatically and accurately co-register satellite video frames and/or register them to a reference map/image. The proposed approach performs non-rigid registration, formulates a Markov Random Fields (MRF) model, while efficient linear programming is employed for reaching the lowest potential of the cost function. The developed approach has been applied and validated on satellite video sequences from Skybox Imaging and compared with a rigid, descriptor-based registration method. Regarding the computational performance, both the MRF-based and the descriptor-based methods were quite efficient, with the first one converging in some minutes and the second in some seconds. Regarding the registration accuracy the proposed MRF-based method significantly outperformed the descriptor-based one in all the performing experiments.
Reconstructing Interlaced High-Dynamic-Range Video Using Joint Learning.
Inchang Choi; Seung-Hwan Baek; Kim, Min H
2017-11-01
For extending the dynamic range of video, it is a common practice to capture multiple frames sequentially with different exposures and combine them to extend the dynamic range of each video frame. However, this approach results in typical ghosting artifacts due to fast and complex motion in nature. As an alternative, video imaging with interlaced exposures has been introduced to extend the dynamic range. However, the interlaced approach has been hindered by jaggy artifacts and sensor noise, leading to concerns over image quality. In this paper, we propose a data-driven approach for jointly solving two specific problems of deinterlacing and denoising that arise in interlaced video imaging with different exposures. First, we solve the deinterlacing problem using joint dictionary learning via sparse coding. Since partial information of detail in differently exposed rows is often available via interlacing, we make use of the information to reconstruct details of the extended dynamic range from the interlaced video input. Second, we jointly solve the denoising problem by tailoring sparse coding to better handle additive noise in low-/high-exposure rows, and also adopt multiscale homography flow to temporal sequences for denoising. We anticipate that the proposed method will allow for concurrent capture of higher dynamic range video frames without suffering from ghosting artifacts. We demonstrate the advantages of our interlaced video imaging compared with the state-of-the-art high-dynamic-range video methods.
Addison, Paul S; Jacquel, Dominique; Foo, David M H; Borg, Ulf R
2017-11-09
The robust monitoring of heart rate from the video-photoplethysmogram (video-PPG) during challenging conditions requires new analysis techniques. The work reported here extends current research in this area by applying a motion tolerant algorithm to extract high quality video-PPGs from a cohort of subjects undergoing marked heart rate changes during a hypoxic challenge, and exhibiting a full range of skin pigmentation types. High uptimes in reported video-based heart rate (HR vid ) were targeted, while retaining high accuracy in the results. Ten healthy volunteers were studied during a double desaturation hypoxic challenge. Video-PPGs were generated from the acquired video image stream and processed to generate heart rate. HR vid was compared to the pulse rate posted by a reference pulse oximeter device (HR p ). Agreement between video-based heart rate and that provided by the pulse oximeter was as follows: Bias = - 0.21 bpm, RMSD = 2.15 bpm, least squares fit gradient = 1.00 (Pearson R = 0.99, p < 0.0001), with a 98.78% reporting uptime. The difference between the HR vid and HR p exceeded 5 and 10 bpm, for 3.59 and 0.35% of the reporting time respectively, and at no point did these differences exceed 25 bpm. Excellent agreement was found between the HR vid and HR p in a study covering the whole range of skin pigmentation types (Fitzpatrick scales I-VI), using standard room lighting and with moderate subject motion. Although promising, further work should include a larger cohort with multiple subjects per Fitzpatrick class combined with a more rigorous motion and lighting protocol.
Games people play: How video games improve probabilistic learning.
Schenk, Sabrina; Lech, Robert K; Suchan, Boris
2017-09-29
Recent research suggests that video game playing is associated with many cognitive benefits. However, little is known about the neural mechanisms mediating such effects, especially with regard to probabilistic categorization learning, which is a widely unexplored area in gaming research. Therefore, the present study aimed to investigate the neural correlates of probabilistic classification learning in video gamers in comparison to non-gamers. Subjects were scanned in a 3T magnetic resonance imaging (MRI) scanner while performing a modified version of the weather prediction task. Behavioral data yielded evidence for better categorization performance of video gamers, particularly under conditions characterized by stronger uncertainty. Furthermore, a post-experimental questionnaire showed that video gamers had acquired higher declarative knowledge about the card combinations and the related weather outcomes. Functional imaging data revealed for video gamers stronger activation clusters in the hippocampus, the precuneus, the cingulate gyrus and the middle temporal gyrus as well as in occipital visual areas and in areas related to attentional processes. All these areas are connected with each other and represent critical nodes for semantic memory, visual imagery and cognitive control. Apart from this, and in line with previous studies, both groups showed activation in brain areas that are related to attention and executive functions as well as in the basal ganglia and in memory-associated regions of the medial temporal lobe. These results suggest that playing video games might enhance the usage of declarative knowledge as well as hippocampal involvement and enhances overall learning performance during probabilistic learning. In contrast to non-gamers, video gamers showed better categorization performance, independently of the uncertainty of the condition. Copyright © 2017 Elsevier B.V. All rights reserved.
Youk, Ji Hyun; Jung, Inkyung; Yoon, Jung Hyun; Kim, Sung Hun; Kim, You Me; Lee, Eun Hye; Jeong, Sun Hye; Kim, Min Jung
2016-09-01
Our aim was to compare the inter-observer variability and diagnostic performance of the Breast Imaging Reporting and Data System (BI-RADS) lexicon for breast ultrasound of static and video images. Ninety-nine breast masses visible on ultrasound examination from 95 women 19-81 y of age at five institutions were enrolled in this study. They were scheduled to undergo biopsy or surgery or had been stable for at least 2 y of ultrasound follow-up after benign biopsy results or typically benign findings. For each mass, representative long- and short-axis static ultrasound images were acquired; real-time long- and short-axis B-mode video images through the mass area were separately saved as cine clips. Each image was reviewed independently by five radiologists who were asked to classify ultrasound features according to the fifth edition of the BI-RADS lexicon. Inter-observer variability was assessed using kappa (κ) statistics. Diagnostic performance on static and video images was compared using the area under the receiver operating characteristic curve. No significant difference was found in κ values between static and video images for all descriptors, although κ values of video images were higher than those of static images for shape, orientation, margin and calcifications. After receiver operating characteristic curve analysis, the video images (0.83, range: 0.77-0.87) had higher areas under the curve than the static images (0.80, range: 0.75-0.83; p = 0.08). Inter-observer variability and diagnostic performance of video images was similar to that of static images on breast ultrasonography according to the new edition of BI-RADS. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Experimental studies of glass refining
NASA Technical Reports Server (NTRS)
Subramanian, R. S.; Cole, R.; Kondos, P.
1984-01-01
The basic components of the experimental apparatus were selected and acquired. Techniques were developed for the fabrication of the special crucibles necessary for the experiments. Arrangements were made for the analysis of glass and gas bubble samples for composition information. Donations of major equipment were received for this project from Owens, Illinois where a similar study had been conducted a few year ago. Decisions were made regarding the actual glass composition to be used, the gas to be used in the first experiments, and the temperatures at which the experiments should be conducted. A microcomputer was acquired, and work was begun on interfacing the video analyzer to it.
TRW Video News: Chandra X-ray Observatory
NASA Technical Reports Server (NTRS)
1999-01-01
This NASA Kennedy Space Center sponsored video release presents live footage of the Chandra X-ray Observatory prior to STS-93 as well as several short animations recreating some of its activities in space. These animations include a Space Shuttle fly-by with Chandra, two perspectives of Chandra's deployment from the Shuttle, the Chandra deployment orbit sequence, the Initial Upper Stage (IUS) first stage burn, and finally a "beauty shot", which represents another animated view of Chandra in space.
Audiovisual focus of attention and its application to Ultra High Definition video compression
NASA Astrophysics Data System (ADS)
Rerabek, Martin; Nemoto, Hiromi; Lee, Jong-Seok; Ebrahimi, Touradj
2014-02-01
Using Focus of Attention (FoA) as a perceptual process in image and video compression belongs to well-known approaches to increase coding efficiency. It has been shown that foveated coding, when compression quality varies across the image according to region of interest, is more efficient than the alternative coding, when all region are compressed in a similar way. However, widespread use of such foveated compression has been prevented due to two main conflicting causes, namely, the complexity and the efficiency of algorithms for FoA detection. One way around these is to use as much information as possible from the scene. Since most video sequences have an associated audio, and moreover, in many cases there is a correlation between the audio and the visual content, audiovisual FoA can improve efficiency of the detection algorithm while remaining of low complexity. This paper discusses a simple yet efficient audiovisual FoA algorithm based on correlation of dynamics between audio and video signal components. Results of audiovisual FoA detection algorithm are subsequently taken into account for foveated coding and compression. This approach is implemented into H.265/HEVC encoder producing a bitstream which is fully compliant to any H.265/HEVC decoder. The influence of audiovisual FoA in the perceived quality of high and ultra-high definition audiovisual sequences is explored and the amount of gain in compression efficiency is analyzed.
Subjective evaluation of HEVC in mobile devices
NASA Astrophysics Data System (ADS)
Garcia, Ray; Kalva, Hari
2013-03-01
Mobile compute environments provide a unique set of user needs and expectations that designers must consider. With increased multimedia use in mobile environments, video encoding methods within the smart phone market segment are key factors that contribute to positive user experience. Currently available display resolutions and expected cellular bandwidth are major factors the designer must consider when determining which encoding methods should be supported. The desired goal is to maximize the consumer experience, reduce cost, and reduce time to market. This paper presents a comparative evaluation of the quality of user experience when HEVC and AVC/H.264 video coding standards were used. The goal of the study was to evaluate any improvements in user experience when using HEVC. Subjective comparisons were made between H.264/AVC and HEVC encoding standards in accordance with Doublestimulus impairment scale (DSIS) as defined by ITU-R BT.500-13. Test environments are based on smart phone LCD resolutions and expected cellular bit rates, such as 200kbps and 400kbps. Subjective feedback shows both encoding methods are adequate at 400kbps constant bit rate. However, a noticeable consumer experience gap was observed for 200 kbps. Significantly less H.264 subjective quality is noticed with video sequences that have multiple objects moving and no single point of visual attraction. Video sequences with single points of visual attraction or few moving objects tended to have higher H.264 subjective quality.
Template-Based 3D Reconstruction of Non-rigid Deformable Object from Monocular Video
NASA Astrophysics Data System (ADS)
Liu, Yang; Peng, Xiaodong; Zhou, Wugen; Liu, Bo; Gerndt, Andreas
2018-06-01
In this paper, we propose a template-based 3D surface reconstruction system of non-rigid deformable objects from monocular video sequence. Firstly, we generate a semi-dense template of the target object with structure from motion method using a subsequence video. This video can be captured by rigid moving camera orienting the static target object or by a static camera observing the rigid moving target object. Then, with the reference template mesh as input and based on the framework of classical template-based methods, we solve an energy minimization problem to get the correspondence between the template and every frame to get the time-varying mesh to present the deformation of objects. The energy terms combine photometric cost, temporal and spatial smoothness cost as well as as-rigid-as-possible cost which can enable elastic deformation. In this paper, an easy and controllable solution to generate the semi-dense template for complex objects is presented. Besides, we use an effective iterative Schur based linear solver for the energy minimization problem. The experimental evaluation presents qualitative deformation objects reconstruction results with real sequences. Compare against the results with other templates as input, the reconstructions based on our template have more accurate and detailed results for certain regions. The experimental results show that the linear solver we used performs better efficiency compared to traditional conjugate gradient based solver.
The Interplay of Representations and Patterns of Classroom Discourse in Science Teaching Sequences
ERIC Educational Resources Information Center
Tang, Kok-Sing
2016-01-01
The purpose of this study is to examines the relationship between the communicative approach of classroom talk and the modes of representations used by science teachers. Based on video data from two physics classrooms in Singapore, a recurring pattern in the relationship was observed as the teaching sequence of a lesson unfolded. It was found that…
ERIC Educational Resources Information Center
de Milliano, Ilona; van Gelderen, Amos; Sleegers, Peter
2016-01-01
This study examines the relationship between types and sequences of self-regulated reading activities in task-oriented reading with quality of task achievement of 51 low-achieving adolescents (Grade 8). The study used think aloud combined with video observations to analyse the students' approach of a content-area reading task in the stages of…
ERIC Educational Resources Information Center
Shahrill, Masitah; Clarke, David J.
2014-01-01
A teachers' practice cannot be characterised by a single lesson, hence comparison is best made with lesson sequences that better sample the diversity of a teacher's practice. In this study, we video recorded lesson sequences in four Year 8 mathematics classrooms, as well as interviewed each of the four teachers in Brunei Darussalam. Because of our…
NASA Astrophysics Data System (ADS)
Ciaramello, Francis M.; Hemami, Sheila S.
2007-02-01
For members of the Deaf Community in the United States, current communication tools include TTY/TTD services, video relay services, and text-based communication. With the growth of cellular technology, mobile sign language conversations are becoming a possibility. Proper coding techniques must be employed to compress American Sign Language (ASL) video for low-rate transmission while maintaining the quality of the conversation. In order to evaluate these techniques, an appropriate quality metric is needed. This paper demonstrates that traditional video quality metrics, such as PSNR, fail to predict subjective intelligibility scores. By considering the unique structure of ASL video, an appropriate objective metric is developed. Face and hand segmentation is performed using skin-color detection techniques. The distortions in the face and hand regions are optimally weighted and pooled across all frames to create an objective intelligibility score for a distorted sequence. The objective intelligibility metric performs significantly better than PSNR in terms of correlation with subjective responses.
SCTP as scalable video coding transport
NASA Astrophysics Data System (ADS)
Ortiz, Jordi; Graciá, Eduardo Martínez; Skarmeta, Antonio F.
2013-12-01
This study presents an evaluation of the Stream Transmission Control Protocol (SCTP) for the transport of the scalable video codec (SVC), proposed by MPEG as an extension to H.264/AVC. Both technologies fit together properly. On the one hand, SVC permits to split easily the bitstream into substreams carrying different video layers, each with different importance for the reconstruction of the complete video sequence at the receiver end. On the other hand, SCTP includes features, such as the multi-streaming and multi-homing capabilities, that permit to transport robustly and efficiently the SVC layers. Several transmission strategies supported on baseline SCTP and its concurrent multipath transfer (CMT) extension are compared with the classical solutions based on the Transmission Control Protocol (TCP) and the Realtime Transmission Protocol (RTP). Using ns-2 simulations, it is shown that CMT-SCTP outperforms TCP and RTP in error-prone networking environments. The comparison is established according to several performance measurements, including delay, throughput, packet loss, and peak signal-to-noise ratio of the received video.
Multimodal flexible cystoscopy for creating co-registered panoramas of the bladder urothelium
NASA Astrophysics Data System (ADS)
Seibel, Eric J.; Soper, Timothy D.; Burkhardt, Matthew R.; Porter, Michael P.; Yoon, W. Jong
2012-02-01
Bladder cancer is the most expensive cancer to treat due to the high rate of recurrence. Though white light cystoscopy is the gold standard for bladder cancer surveillance, the advent of fluorescence biomarkers provides an opportunity to improve sensitivity for early detection and reduced recurrence resulting from more accurate excision. Ideally, fluorescence information could be combined with standard reflectance images to provide multimodal views of the bladder wall. The scanning fiber endoscope (SFE) of 1.2mm in diameter is able to acquire wide-field multimodal video from a bladder phantom with fluorescence cancer "hot-spots". The SFE generates images by scanning red, green, and blue (RGB) laser light and detects the backscatter signal for reflectance video of 500-line resolution at 30 frames per second. We imaged a bladder phantom with painted vessels and mimicked fluorescent lesions by applying green fluorescent microspheres to the surface. By eliminating the green laser illumination, simultaneous reflectance and fluorescence images can be acquired at the same field of view, resolution, and frame rate. Moreover, the multimodal SFE is combined with a robotic steering mechanism and image stitching software as part of a fully automated bladder surveillance system. Using this system, the SFE can be reliably articulated over the entire 360° bladder surface. Acquired images can then be stitched into a multimodal 3D panorama of the bladder using software developed in our laboratory. In each panorama, the fluorescence images are exactly co-registered with RGB reflectance.
Introduction: Intradural Spinal Surgery video supplement.
McCormick, Paul C
2014-09-01
This Neurosurgical Focus video supplement contains detailed narrated videos of a broad range of intradural pathology such as neoplasms, including intramedullary, extramedullary, and dumbbell tumors, vascular malformations, functional disorders, and rare conditions that are often overlooked or misdiagnosed such as arachnoid cysts, ventral spinal cord herniation, and dorsal arachnoid web. The intent of this supplement is to provide meaningful educational and instructional content at all levels of training and practice. As such, the selected video submissions each provide a comprehensive detailed narrative description and coordinated video that contains the entire spectrum of relevant information including imaging, operative setup and positioning, and exposure, as well as surgical strategies, techniques, and sequencing toward the safe and effective achievement of the operative objective. This level of detail often necessitated a more lengthy video duration than is typically presented in oral presentations or standard video clips from peer reviewed publications. Unfortunately, space limitations precluded the inclusion of several other excellent video submissions in this supplement. While most videos in this supplement reflect standard operative approaches and techniques there are also submissions that describe innovative exposures and techniques that have expanded surgical options such as ventral approaches, stereotactic guidance, and minimally invasive exposures. There is some redundancy in both the topics and techniques both to underscore fundamental surgical principles as well as to provide complementary perspective from different surgeons. It has been my privilege to serve as guest editor for this video supplement and I would like to extend my appreciation to Mark Bilsky, Bill Krauss, and Sander Connolly for reviewing the large number submitted videos. Most of all, I would like to thank the authors for their skill and effort in the preparation of the outstanding videos that constitute this video supplement.
A new method for digital video documentation in surgical procedures and minimally invasive surgery.
Wurnig, P N; Hollaus, P H; Wurnig, C H; Wolf, R K; Ohtsuka, T; Pridun, N S
2003-02-01
Documentation of surgical procedures is limited to the accuracy of description, which depends on the vocabulary and the descriptive prowess of the surgeon. Even analog video recording could not solve the problem of documentation satisfactorily due to the abundance of recorded material. By capturing the video digitally, most problems are solved in the circumstances described in this article. We developed a cheap and useful digital video capturing system that consists of conventional computer components. Video images and clips can be captured intraoperatively and are immediately available. The system is a commercial personal computer specially configured for digital video capturing and is connected by wire to the video tower. Filming was done with a conventional endoscopic video camera. A total of 65 open and endoscopic procedures were documented in an orthopedic and a thoracic surgery unit. The median number of clips per surgical procedure was 6 (range, 1-17), and the median storage volume was 49 MB (range, 3-360 MB) in compressed form. The median duration of a video clip was 4 min 25 s (range, 45 s to 21 min). Median time for editing a video clip was 12 min for an advanced user (including cutting, title for the movie, and compression). The quality of the clips renders them suitable for presentations. This digital video documentation system allows easy capturing of intraoperative video sequences in high quality. All possibilities of documentation can be performed. With the use of an endoscopic video camera, no compromises with respect to sterility and surgical elbowroom are necessary. The cost is much lower than commercially available systems, and setting changes can be performed easily without trained specialists.
NASA Astrophysics Data System (ADS)
Eaton, Adam; Vincely, Vinoin; Lloyd, Paige; Hugenberg, Kurt; Vishwanath, Karthik
2017-03-01
Video Photoplethysmography (VPPG) is a numerical technique to process standard RGB video data of exposed human skin and extracting the heart-rate (HR) from the skin areas. Being a non-contact technique, VPPG has the potential to provide estimates of subject's heart-rate, respiratory rate, and even the heart rate variability of human subjects with potential applications ranging from infant monitors, remote healthcare and psychological experiments, particularly given the non-contact and sensor-free nature of the technique. Though several previous studies have reported successful correlations in HR obtained using VPPG algorithms to HR measured using the gold-standard electrocardiograph, others have reported that these correlations are dependent on controlling for duration of the video-data analyzed, subject motion, and ambient lighting. Here, we investigate the ability of two commonly used VPPG-algorithms in extraction of human heart-rates under three different laboratory conditions. We compare the VPPG HR values extracted across these three sets of experiments to the gold-standard values acquired by using an electrocardiogram or a commercially available pulseoximeter. The two VPPG-algorithms were applied with and without KLT-facial feature tracking and detection algorithms from the Computer Vision MATLAB® toolbox. Results indicate that VPPG based numerical approaches have the ability to provide robust estimates of subject HR values and are relatively insensitive to the devices used to record the video data. However, they are highly sensitive to conditions of video acquisition including subject motion, the location, size and averaging techniques applied to regions-of-interest as well as to the number of video frames used for data processing.
Classification of a set of vectors using self-organizing map- and rule-based technique
NASA Astrophysics Data System (ADS)
Ae, Tadashi; Okaniwa, Kaishirou; Nosaka, Kenzaburou
2005-02-01
There exist various objects, such as pictures, music, texts, etc., around our environment. We have a view for these objects by looking, reading or listening. Our view is concerned with our behaviors deeply, and is very important to understand our behaviors. We have a view for an object, and decide the next action (data selection, etc.) with our view. Such a series of actions constructs a sequence. Therefore, we propose a method which acquires a view as a vector from several words for a view, and apply the vector to sequence generation. We focus on sequences of the data of which a user selects from a multimedia database containing pictures, music, movie, etc... These data cannot be stereotyped because user's view for them changes by each user. Therefore, we represent the structure of the multimedia database as the vector representing user's view and the stereotyped vector, and acquire sequences containing the structure as elements. Such a vector can be classified by SOM (Self-Organizing Map). Hidden Markov Model (HMM) is a method to generate sequences. Therefore, we use HMM of which a state corresponds to the representative vector of user's view, and acquire sequences containing the change of user's view. We call it Vector-state Markov Model (VMM). We introduce the rough set theory as a rule-base technique, which plays a role of classifying the sets of data such as the sets of "Tour".
A method for automatically abstracting visual documents
NASA Technical Reports Server (NTRS)
Rorvig, Mark E.
1994-01-01
Visual documents--motion sequences on film, videotape, and digital recording--constitute a major source of information for the Space Agency, as well as all other government and private sector entities. This article describes a method for automatically selecting key frames from visual documents. These frames may in turn be used to represent the total image sequence of visual documents in visual libraries, hypermedia systems, and training algorithm reduces 51 minutes of video sequences to 134 frames; a reduction of information in the range of 700:1.
Rimmer, James H; Vanderbom, Kerri A; Graham, Ian D
2016-04-01
Supporting the transition of people with newly acquired and existing disability from rehabilitation into community-based health/wellness programs, services, and venues requires rehabilitation professionals to build evidence by capturing successful strategies at the local level, finding innovative ways to translate successful practices to other communities, and ultimately to upgrade and maintain their applicability and currency for future scale-up. This article describes a knowledge-to-practice framework housed in a national resource and practice center that will support therapists and other rehabilitation professionals in building and maintaining a database of successful health/wellness guidelines, recommendations, and adaptations to promote community health inclusion for people with disabilities. A framework was developed in the National Center on Health, Physical Activity and Disability (NCHPAD) to systematically build and advance the evidence base of health/wellness programs, practices, and services applicable to people with disabilities. N-KATS (NCHPAD Knowledge Adaptation, Translation, and Scale-up) has 4 sequencing strategies: strategy 1-new evidence- and practice-based knowledge is collected and adapted for the local context (ie, community); strategy 2-customized resources are effectively disseminated to key stakeholders including rehabilitation professionals with appropriate training tools; strategy 3-NCHPAD staff serve as facilitators assisting key stakeholders in implementing recommendations; strategy 4-successful elements of practice (eg, guideline, recommendation, adaptation) are archived and scaled to other rehabilitation providers. The N-KATS framework supports the role of rehabilitation professionals as knowledge brokers, facilitators, and users in a collaborative, dynamic structure that will grow and be sustained over time through the NCHPAD.Video abstract available for additional insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A130).
Exploring Techniques for Vision Based Human Activity Recognition: Methods, Systems, and Evaluation
Xu, Xin; Tang, Jinshan; Zhang, Xiaolong; Liu, Xiaoming; Zhang, Hong; Qiu, Yimin
2013-01-01
With the wide applications of vision based intelligent systems, image and video analysis technologies have attracted the attention of researchers in the computer vision field. In image and video analysis, human activity recognition is an important research direction. By interpreting and understanding human activities, we can recognize and predict the occurrence of crimes and help the police or other agencies react immediately. In the past, a large number of papers have been published on human activity recognition in video and image sequences. In this paper, we provide a comprehensive survey of the recent development of the techniques, including methods, systems, and quantitative evaluation of the performance of human activity recognition. PMID:23353144
Optimal space communications techniques. [discussion of video signals and delta modulation
NASA Technical Reports Server (NTRS)
Schilling, D. L.
1974-01-01
The encoding of video signals using the Song Adaptive Delta Modulator (Song ADM) is discussed. The video signals are characterized as a sequence of pulses having arbitrary height and width. Although the ADM is suited to tracking signals having fast rise times, it was found that the DM algorithm (which permits an exponential rise for estimating an input step) results in a large overshoot and an underdamped response to the step. An overshoot suppression algorithm which significantly reduces the ringing while not affecting the rise time is presented along with formuli for the rise time and the settling time. Channel errors and their effect on the DM encoded bit stream were investigated.
NASA Astrophysics Data System (ADS)
Crone, T. J.; Mittelstaedt, E. L.; Fornari, D. J.
2014-12-01
Fluid flow rates through high-temperature mid-ocean ridge hydrothermal vents are likely quite sensitive to poroelastic forcing mechanisms such as tidal loading and tectonic activity. Because poroelastic deformation and flow perturbations are estimated to extend to considerable depths within young oceanic crust, observations of flow rate changes at seafloor vents have the potential to provide constraints on the flow geometry and permeability structure of the underlying hydrothermal systems, as well as the quantities of heat and chemicals they exchange with overlying ocean, and the potential biological productivity of ecosystems they host. To help provide flow rate measurements in these challenging environments, we have developed two new optical flow oriented technologies. The first is a new form of Optical Plume Velocimetry (OPV) which relies on single-frame temporal cross-correlation to obtain time-averaged image velocity fields from short video sequences. The second is the VentCam, a deep sea camera system that can collect high-frame-rate video sequences at focused hydrothermal vents suitable for analysis with OPV. During the July 2014 R/V Atlantis/Alvin expedition to Axial Seamount, we deployed the VentCam at the ~300C Phoenix vent within the ASHES vent field and positioned it with DSRV Alvin. We collected 24 seconds of video at 50 frames per second every half-hour for approximately 10 days beginning July 22nd. We are currently applying single-frame lag OPV to these videos to estimate relative and absolute fluid flow rates through this vent. To explore the relationship between focused and diffuse venting, we deployed a second optical flow camera, the Diffuse Effluent Measurement System (DEMS), adjacent to this vent at a fracture within the lava carapace where low-T (~30C) fluids were exiting. This system collected video sequences and diffuse flow measurements at overlapping time intervals. Here we present the preliminary results of our work with VentCam and OPV, and comparisons with results from the DEMS camera.
Serotype IV Sequence Type 468 Group B Streptococcus Neonatal Invasive Disease, Minnesota, USA.
Teatero, Sarah; Ferrieri, Patricia; Fittipaldi, Nahuel
2016-11-01
To further understand the emergence of serotype IV group B Streptococcus (GBS) invasive disease, we used whole-genome sequencing to characterize 3 sequence type 468 strains isolated from neonates in Minnesota, USA. We found that strains of tetracycline-resistant sequence type 468 GBS have acquired virulence genes from a putative clonal complex 17 GBS donor by recombination.
CRISPR interference and priming varies with individual spacer sequences
Xue, Chaoyou; Seetharam, Arun S.; Musharova, Olga; Severinov, Konstantin; J. Brouns, Stan J.; Severin, Andrew J.; Sashital, Dipali G.
2015-01-01
CRISPR–Cas (clustered regularly interspaced short palindromic repeats-CRISPR associated) systems allow bacteria to adapt to infection by acquiring ‘spacer’ sequences from invader DNA into genomic CRISPR loci. Cas proteins use RNAs derived from these loci to target cognate sequences for destruction through CRISPR interference. Mutations in the protospacer adjacent motif (PAM) and seed regions block interference but promote rapid ‘primed’ adaptation. Here, we use multiple spacer sequences to reexamine the PAM and seed sequence requirements for interference and priming in the Escherichia coli Type I-E CRISPR–Cas system. Surprisingly, CRISPR interference is far more tolerant of mutations in the seed and the PAM than previously reported, and this mutational tolerance, as well as priming activity, is highly dependent on spacer sequence. We identify a large number of functional PAMs that can promote interference, priming or both activities, depending on the associated spacer sequence. Functional PAMs are preferentially acquired during unprimed ‘naïve’ adaptation, leading to a rapid priming response following infection. Our results provide numerous insights into the importance of both spacer and target sequences for interference and priming, and reveal that priming is a major pathway for adaptation during initial infection. PMID:26586800
Wang, Haibin; Jiang, Jiafu; Chen, Sumei; Qi, Xiangyu; Peng, Hui; Li, Pirui; Song, Aiping; Guan, Zhiyong; Fang, Weimin; Liao, Yuan; Chen, Fadi
2013-01-01
Background Simple sequence repeats (SSRs) are ubiquitous in eukaryotic genomes. Chrysanthemum is one of the largest genera in the Asteraceae family. Only few Chrysanthemum expressed sequence tag (EST) sequences have been acquired to date, so the number of available EST-SSR markers is very low. Methodology/Principal Findings Illumina paired-end sequencing technology produced over 53 million sequencing reads from C. nankingense mRNA. The subsequent de novo assembly yielded 70,895 unigenes, of which 45,789 (64.59%) unigenes showed similarity to the sequences in NCBI database. Out of 45,789 sequences, 107 have hits to the Chrysanthemum Nr protein database; 679 and 277 sequences have hits to the database of Helianthus and Lactuca species, respectively. MISA software identified a large number of putative EST-SSRs, allowing 1,788 primer pairs to be designed from the de novo transcriptome sequence and a further 363 from archival EST sequence. Among 100 primer pairs randomly chosen, 81 markers have amplicons and 20 are polymorphic for genotypes analysis in Chrysanthemum. The results showed that most (but not all) of the assays were transferable across species and that they exposed a significant amount of allelic diversity. Conclusions/Significance SSR markers acquired by transcriptome sequencing are potentially useful for marker-assisted breeding and genetic analysis in the genus Chrysanthemum and its related genera. PMID:23626799
Hands-on Simulation versus Traditional Video-learning in Teaching Microsurgery Technique
SAKAMOTO, Yusuke; OKAMOTO, Sho; SHIMIZU, Kenzo; ARAKI, Yoshio; HIRAKAWA, Akihiro; WAKABAYASHI, Toshihiko
2017-01-01
Bench model hands-on learning may be more effective than traditional didactic practice in some surgical fields. However, this has not been reported for microsurgery. Our study objective was to demonstrate the efficacy of bench model hands-on learning in acquiring microsuturing skills. The secondary objective was to evaluate the aptitude for microsurgery based on personality assessment. Eighty-six medical students comprising 62 men and 24 women were randomly assigned to either 20 min of hands-on learning with a bench model simulator or 20 min of video-learning using an instructional video. They then practiced microsuturing for 40 min. Each student then made three knots, and the time to complete the task was recorded. The final products were scored by two independent graders in a blind fashion. All participants then took a personality test, and their microsuture test scores and the time to complete the task were compared. The time to complete the task was significantly shorter in the simulator group than in the video-learning group. The final product scores tended to be higher with simulator-learning than with video-learning, but the difference was not significant. Students with high “extraversion” scores on the personality inventory took a shorter time to complete the suturing test. Simulator-learning was more effective for microsurgery training than video instruction, especially in understanding the procedure. There was a weak association between personality traits and microsurgery skill. PMID:28381653
AIDS education video: Karate Kids.
Lowry, C
1993-01-01
Street Kids International, in cooperation with the World Health Organization and the National Film Board of Canada, has developed an animated action-adventure video, "Karate Kids," as part of a cross-cultural program of health education that concerns human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) and targets street children in developing countries. Simple, but explicit, information is delivered during the 22-minute cartoon; the package also includes a training book for educators, and a pocket comic book. Distributed in 17 languages (it is readily adapted to new language versions, independent of the original producers) in over 100 countries, the video is shown in community theaters, hospitals, schools, and prisons, and out of the backs of trucks. It is easily copied, which is encouraged. After 3 years in distribution, field evaluation has demonstrated that the greatest strength of the video is its ability to stimulate discussion where no discussion was taking place before. Critics include those who believe there is no need for it and those who feel it should be used alone. The results of one evaluation study showed use of the video alone was insufficient; those of a cross-cultural participatory evaluation survey indicated a significant impact on knowledge and attitudes when the video was followed by discussion. Another significant aspect of the project is that it treats street children with respect; they are actors, not victims, who have legitimate needs and rights. They become visible in a world that is often unaware of them.
Automatic acquisition of motion trajectories: tracking hockey players
NASA Astrophysics Data System (ADS)
Okuma, Kenji; Little, James J.; Lowe, David
2003-12-01
Computer systems that have the capability of analyzing complex and dynamic scenes play an essential role in video annotation. Scenes can be complex in such a way that there are many cluttered objects with different colors, shapes and sizes, and can be dynamic with multiple interacting moving objects and a constantly changing background. In reality, there are many scenes that are complex, dynamic, and challenging enough for computers to describe. These scenes include games of sports, air traffic, car traffic, street intersections, and cloud transformations. Our research is about the challenge of inventing a descriptive computer system that analyzes scenes of hockey games where multiple moving players interact with each other on a constantly moving background due to camera motions. Ultimately, such a computer system should be able to acquire reliable data by extracting the players" motion as their trajectories, querying them by analyzing the descriptive information of data, and predict the motions of some hockey players based on the result of the query. Among these three major aspects of the system, we primarily focus on visual information of the scenes, that is, how to automatically acquire motion trajectories of hockey players from video. More accurately, we automatically analyze the hockey scenes by estimating parameters (i.e., pan, tilt, and zoom) of the broadcast cameras, tracking hockey players in those scenes, and constructing a visual description of the data by displaying trajectories of those players. Many technical problems in vision such as fast and unpredictable players' motions and rapid camera motions make our challenge worth tackling. To the best of our knowledge, there have not been any automatic video annotation systems for hockey developed in the past. Although there are many obstacles to overcome, our efforts and accomplishments would hopefully establish the infrastructure of the automatic hockey annotation system and become a milestone for research in automatic video annotation in this domain.
Sumanapala, Dilini K; Walbrin, Jon; Kirsch, Louise P; Cross, Emily S
2018-01-01
Studies investigating human motor learning and movement perception have shown that similar sensorimotor brain regions are engaged when we observe or perform action sequences. However, the way these networks enable translation of complex observed actions into motor commands-such as in the context of dance-remains poorly understood. Emerging evidence suggests that the ability to encode specific visuospatial and kinematic movement properties encountered via different routes of sensorimotor experience may be an integral component of action learning throughout development. Using a video game-based dance training paradigm, we demonstrate that patterns of voxel activity in visual and sensorimotor brain regions when perceiving movements following training are related to the sensory modalities through which these movements were encountered during whole-body dance training. Compared to adolescents, young adults in this study demonstrated more distinctive patterns of voxel activity in visual cortices in relation to different types of sensorimotor experience. This finding suggests that cortical maturity might influence the extent to which prior sensorimotor experiences shape brain activity when watching others in action, and potentially impact how we acquire new motor skills. © 2018 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.
The Environmental Quality Instructional Resources Center in Columbus, Ohio, acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. This publication contains abstracts and indexes to selected…
ERIC Educational Resources Information Center
Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.
The Environmental Quality Instructional Resources Center in Columbus, Ohio, acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. In addition some materials related to hazardous materials,…
ERIC Educational Resources Information Center
Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.
The Environmental Quality Instructional Resources Center in Columbus, Ohio, acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. In addition some materials related to pesticides, hazardous…
ERIC Educational Resources Information Center
Ohio State Univ., Columbus, OH. Information Reference Center for Science, Mathematics, and Environmental Education.
The Environmental Quality Instructional Resources Center in Columbus, Ohio, acquires, reviews, indexes, and announces both print (books, modules, units, etc.) and non-print (films, slides, video tapes, etc.) materials related to water quality and water resources education and instruction. In addition some materials related to pesticides, hazardous…
Improving the Quality of Staff and Participant Interaction in an Acquired Brain Injury Organization
ERIC Educational Resources Information Center
Guercio, John M.; Dixon, Mark R.
2010-01-01
Weekly observations of direct-care staff in a facility for persons with brain injury yielded less than optimal interactional style with facility residents. Following an observational baseline, staff were asked to self-rate a 15-min video sample of their interaction behavior with participants on their unit. They were then asked to compare their…
February 1994 ice storm: forest resource damage assessment in northern Mississippi
Dennis M. Jacobs
2000-01-01
During February 8Â11, 1994, a severe winter storm moved from Texas and Oklahoma to the mid-Atlantic depositing in northern Mississippi a major ice accumulation of 3 to 6 inches. An assessment of forest resource damage was initiated immediately after the storm by performing an airborne video mission to acquire aerial imagery linked to global positioning coordinates....
Espinheira Gomes, Filipe; Ledbetter, Eric
2018-05-11
To describe an indirect funduscopy imaging technique for dogs and cats using low cost and widely available equipment: a smartphone, a three-dimensional (3D) printed indirect lens adapter, and a 40 diopters (D) indirect ophthalmoscopy lens. Fundus videography was performed in dogs and cats using a 40D indirect ophthalmoscopy lens and a smartphone fitted with a 3D printed indirect lens adapter. All animals were pharmacologically dilated with topical tropicamide 1% solution. Eyelid opening and video recording were performed using standard binocular indirect ophthalmoscopy technique. All videos were uploaded to a computer, and still images were selected and acquired for archiving purposes. Fundic images were manipulated to represent the true anatomy of the fundus. It was possible to promptly obtain good quality images from normal and diseased retinas using the nonpatented 3D printed, lens adapter for a smartphone. Fundic imaging using a smartphone can be performed with minimal investment. This simple imaging modality can be used by veterinary ophthalmologists and general practitioners to acquire, archive, and share images of the retina. The quality of images obtained will likely improve with developments in smartphone camera software and hardware. © 2018 American College of Veterinary Ophthalmologists.
Children's Acquisition of English Onset and Coda /l/: Articulatory Evidence
Demuth, Katherine
2015-01-01
Purpose The goal of this study was to better understand how and when onset /l/ (leap) and coda /l/ (peel) are acquired by children by examining both the articulations involved and adults' perceptions of the produced segments. Method Twenty-five typically developing Australian English–speaking children aged 3;0 (years;months) to 7;11 participated in an elicited imitation task, during which audio, video, and lingual ultrasound images were collected. Transcribers perceptually rated audio, whereas video and ultrasound images were visually examined for the presence of adult-like articulations. Results Data from this study establish that for Australian English–learning children, coda /l/s are acquired later than onset /l/s, and older children produce greater proportions of adultlike /l/s in both onset and coda positions, roughly following established norms for American English–speaking children. However, although perceptibility of coda /l/s was correlated with their articulations, onset /l/s were nearly uniformly perceived as adultlike despite substantial variation in the articulations used to produce them. Conclusions The disparity in the production and perception of children's singleton onset /l/s is linked to both physiological and phonological development. Suggestions are made for future research to tease these factors apart. PMID:25321384
Vogel, Adam P; Block, Susan; Kefalianos, Elaina; Onslow, Mark; Eadie, Patricia; Barth, Ben; Conway, Laura; Mundt, James C; Reilly, Sheena
2015-04-01
To investigate the feasibility of adopting automated interactive voice response (IVR) technology for remotely capturing standardized speech samples from stuttering children. Participants were 10 6-year-old stuttering children. Their parents called a toll-free number from their homes and were prompted to elicit speech from their children using a standard protocol involving conversation, picture description and games. The automated IVR system was implemented using an off-the-shelf telephony software program and delivered by a standard desktop computer. The software infrastructure utilizes voice over internet protocol. Speech samples were automatically recorded during the calls. Video recordings were simultaneously acquired in the home at the time of the call to evaluate the fidelity of the telephone collected samples. Key outcome measures included syllables spoken, percentage of syllables stuttered and an overall rating of stuttering severity using a 10-point scale. Data revealed a high level of relative reliability in terms of intra-class correlation between the video and telephone acquired samples on all outcome measures during the conversation task. Findings were less consistent for speech samples during picture description and games. Results suggest that IVR technology can be used successfully to automate remote capture of child speech samples.
Robustness of remote stress detection from visible spectrum recordings
NASA Astrophysics Data System (ADS)
Kaur, Balvinder; Moses, Sophia; Luthra, Megha; Ikonomidou, Vasiliki N.
2016-05-01
In our recent work, we have shown that it is possible to extract high fidelity timing information of the cardiac pulse wave from visible spectrum videos, which can then be used as a basis for stress detection. In that approach, we used both heart rate variability (HRV) metrics and the differential pulse transit time (dPTT) as indicators of the presence of stress. One of the main concerns in this analysis is its robustness in the presence of noise, as the remotely acquired signal that we call blood wave (BW) signal is degraded with respect to the signal acquired using contact sensors. In this work, we discuss the robustness of our metrics in the presence of multiplicative noise. Specifically, we study the effects of subtle motion due to respiration and changes in illumination levels due to light flickering on the BW signal, the HRV-driven features, and the dPTT. Our sensitivity study involved both Monte Carlo simulations and experimental data from human facial videos, and indicates that our metrics are robust even under moderate amounts of noise. Generated results will help the remote stress detection community with developing requirements for visual spectrum based stress detection systems.
Self Occlusion and Disocclusion in Causal Video Object Segmentation
2015-12-18
computation is parameter- free in contrast to [4, 32, 10]. Taylor et al . [30] perform layer segmentation in longer video sequences leveraging occlusion cues...shows that our method recovers from errors in the first frame (short of failed detection). 4413 image ground truth Lee et al . [19] Grundman et al . [14...Ochs et al . [23] Taylor et al . [30] ours Figure 7. Sample Visual Results on FBMS-59. Comparison of various state-of-the-art methods. Only a single
OpenMP Parallelization and Optimization of Graph-based Machine Learning Algorithms
2016-05-01
composed of hyper - spectral video sequences recording the release of chemical plumes at the Dugway Proving Ground. We use the 329 frames of the...video. Each frame is a hyper - spectral image with dimension 128 × 320 × 129, where 129 is the dimension of the channel of each pixel. The total number of...j=1 . Then we use the nested for- loop to calculate the values of WXY by the formula (1). We then put the corresponding value in an array which
An Adaptive Inpainting Algorithm Based on DCT Induced Wavelet Regularization
2013-01-01
research in image processing. Applications of image inpainting include old films restoration, video inpainting [4], de -interlacing of video sequences...show 5 (a) (b) (c) (d) (e) (f) Fig. 1. Performance of various inpainting algorithms for a cartoon image with text. (a) the original test image; (b...the test image with text; inpainted images by (c) SF (PSNR=37.38 dB); (d) SF-LDCT (PSNR=37.37 dB); (e) MCA (PSNR=37.04 dB); and (f) the proposed
Efficient Use of Video for 3d Modelling of Cultural Heritage Objects
NASA Astrophysics Data System (ADS)
Alsadik, B.; Gerke, M.; Vosselman, G.
2015-03-01
Currently, there is a rapid development in the techniques of the automated image based modelling (IBM), especially in advanced structure-from-motion (SFM) and dense image matching methods, and camera technology. One possibility is to use video imaging to create 3D reality based models of cultural heritage architectures and monuments. Practically, video imaging is much easier to apply when compared to still image shooting in IBM techniques because the latter needs a thorough planning and proficiency. However, one is faced with mainly three problems when video image sequences are used for highly detailed modelling and dimensional survey of cultural heritage objects. These problems are: the low resolution of video images, the need to process a large number of short baseline video images and blur effects due to camera shake on a significant number of images. In this research, the feasibility of using video images for efficient 3D modelling is investigated. A method is developed to find the minimal significant number of video images in terms of object coverage and blur effect. This reduction in video images is convenient to decrease the processing time and to create a reliable textured 3D model compared with models produced by still imaging. Two experiments for modelling a building and a monument are tested using a video image resolution of 1920×1080 pixels. Internal and external validations of the produced models are applied to find out the final predicted accuracy and the model level of details. Related to the object complexity and video imaging resolution, the tests show an achievable average accuracy between 1 - 5 cm when using video imaging, which is suitable for visualization, virtual museums and low detailed documentation.
Flanking sequence determination and specific PCR identification of transgenic wheat B102-1-2.
Cao, Jijuan; Xu, Junyi; Zhao, Tongtong; Cao, Dongmei; Huang, Xin; Zhang, Piqiao; Luan, Fengxia
2014-01-01
The exogenous fragment sequence and flanking sequence between the exogenous fragment and recombinant chromosome of transgenic wheat B102-1-2 were successfully acquired using genome walking technology. The newly acquired exogenous fragment encoded the full-length sequence of transformed genes with transformed plasmid and corresponding functional genes including ubi, vector pBANF-bar, vector pUbiGUSPlus, vector HSP, reporter vector pUbiGUSPlus, promoter ubiquitin, and coli DH1. A specific polymerase chain reaction (PCR) identification method for transgenic wheat B102-1-2 was established on the basis of designed primers according to flanking sequence. This established specific PCR strategy was validated by using transgenic wheat, transgenic corn, transgenic soybean, transgenic rice, and non-transgenic wheat. A specifically amplified target band was observed only in transgenic wheat B102-1-2. Therefore, this method is characterized by high specificity, high reproducibility, rapid identification, and excellent accuracy for the identification of transgenic wheat B102-1-2.
Doorbar-Baptist, Stuart; Adams, Roger; Rebbeck, Trudy
2017-04-01
This study documents a protocol designed to evaluate pelvic floor motor control in men with prostate cancer. It also aims to evaluate the reliability of therapists in rating motor control of pelvic floor muscles (PFMs) using real time ultrasound imaging (RUSI) video clips. We further determine predictors of acquiring motor control. Ninety-one men diagnosed with prostate cancer attending a physiotherapy clinic for pelvic floor exercises were taught detailed pelvic floor motor control exercises by a physiotherapist using trans-abdominal RUSI for biofeedback. A new protocol to rate motor control skill acquisition was developed. Three independent physiotherapists assessed motor control skill attainment by viewing RUSI videos of the contractions. Inter-rater reliability was evaluated using intra-class correlation coefficients. Logistic regression analysis was conducted to identify predictors of successful skill attainment. Acquisition of the skill was compared between pre- and post-operative participants using an independent-group t-test. There was good reliability for rating the RUSI video clips (ICC 0.73 (95%CI 0.59-0.82)) for experienced therapists. Having low BMI and being seen pre-operatively predicted motor skill attainment, accounting for 46.3% of the variance. Significantly more patients trained pre-operatively acquired the skill of pelvic floor control compared with patients initially seen post-operatively (OR 11.87, 95%CI 1.4 to 99.5, p = 0.02). A new protocol to evaluate attainment of pelvic floor control in men with prostate cancer can be assessed reliably from RUSI images, and is most effectively delivered pre-operatively.
Effects of learning context on the acquisition and processing of emotional words in bilinguals.
Brase, Julia; Mani, Nivedita
2017-06-01
Although bilinguals respond differently to emotionally valenced words in their first language (L1) relative to emotionally neutral words, similar effects of emotional valence are hard to come by in second language (L2) processing. We examine the extent to which these differences in first and second language processing are due to the context in which the 2 languages are acquired: L1 is typically acquired in more naturalistic settings (e.g., family) than L2 (e.g., at school). Fifty German-English bilinguals learned unfamiliar German and English negative and neutral words in 2 different learning conditions: One group (emotion video context) watched videos of a person providing definitions of the words with facial and gestural cues, whereas another group (neutral video context) received the same definitions without gestural and emotional cues. Subsequently, participants carried out an emotional Stroop task, a sentence completion task, and a recall task on the words they had just learned. We found that the effect of learning context on the influence of emotional valence on responding was modulated by a) language status, L1 versus L2, and b) task requirement. We suggest that a more nuanced approach is required to capture the differences in emotion effects in the speed versus accuracy of access to words across different learning contexts and different languages, in particular with regard to our finding that bilinguals respond to L2 words in a similar manner as L1 words provided that the learning context is naturalistic and incorporates emotional and prosodic cues. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
An in-line optical image translator with applications in x-ray videography.
Picot, P A; Cardinal, H N; Fenster, A
1990-01-01
Many applications in radiography require, or would benefit from, the ability to translate, i.e. move, an optical image in the detector plane. In this paper, we describe the design and characterization of a prism-based optical image translator for insertion into existing XRII-video imaging systems. A pair of prisms rotatable about the optical axis form a very compact in-line optical image translator for installation in the parallel light path between an x-ray image intensifier and its video camera. Rotation of the prisms translates the XRII optical image on the camera target. With the addition of x-ray and light collimators to limit the image to a single video line, x-ray streak images may be acquired. By rotating an object in the x-ray beam during a streak, a complete computed tomography (CT) data set may be acquired. This image translator can translate an image anywhere in the focal plane of a 50-mm-output lens within a 40-mm-diam circle. The prisms have an aperture of 50 mm, permitting an optical speed of F/2 with a 50-mm output lens. The design is insensitive to angular alignment errors. This image translator is achromatic, since the spectral width of the output phosphorus of image intensifiers is sufficient to introduce blurring in a nonacrhomatic design. A prism-based image translator introduces image distortion, since the prisms do not operate at minimum deviation. The distortion is less than 4% over all parts of a typical detector area, and less than 1% in the central region of the image.(ABSTRACT TRUNCATED AT 250 WORDS)
The use of open data from social media for the creation of 3D georeferenced modeling
NASA Astrophysics Data System (ADS)
Themistocleous, Kyriacos
2016-08-01
There is a great deal of open source video on the internet that is posted by users on social media sites. With the release of low-cost unmanned aerial vehicles, many hobbyists are uploading videos from different locations, especially in remote areas. Using open source data that is available on the internet, this study utilized structure to motion (SfM) as a range imaging technique to estimate 3 dimensional landscape features from 2 dimensional image sequences subtracted from video, applied image distortion correction and geo-referencing. This type of documentation may be necessary for cultural heritage sites that are inaccessible or documentation is difficult, where we can access video from Unmanned Aerial Vehicles (UAV). These 3D models can be viewed using Google Earth, create orthoimage, drawings and create digital terrain modeling for cultural heritage and archaeological purposes in remote or inaccessible areas.
Resolution enhancement of low-quality videos using a high-resolution frame
NASA Astrophysics Data System (ADS)
Pham, Tuan Q.; van Vliet, Lucas J.; Schutte, Klamer
2006-01-01
This paper proposes an example-based Super-Resolution (SR) algorithm of compressed videos in the Discrete Cosine Transform (DCT) domain. Input to the system is a Low-Resolution (LR) compressed video together with a High-Resolution (HR) still image of similar content. Using a training set of corresponding LR-HR pairs of image patches from the HR still image, high-frequency details are transferred from the HR source to the LR video. The DCT-domain algorithm is much faster than example-based SR in spatial domain 6 because of a reduction in search dimensionality, which is a direct result of the compact and uncorrelated DCT representation. Fast searching techniques like tree-structure vector quantization 16 and coherence search1 are also key to the improved efficiency. Preliminary results on MJPEG sequence show promising result of the DCT-domain SR synthesis approach.
A study on multiresolution lossless video coding using inter/intra frame adaptive prediction
NASA Astrophysics Data System (ADS)
Nakachi, Takayuki; Sawabe, Tomoko; Fujii, Tetsuro
2003-06-01
Lossless video coding is required in the fields of archiving and editing digital cinema or digital broadcasting contents. This paper combines a discrete wavelet transform and adaptive inter/intra-frame prediction in the wavelet transform domain to create multiresolution lossless video coding. The multiresolution structure offered by the wavelet transform facilitates interchange among several video source formats such as Super High Definition (SHD) images, HDTV, SDTV, and mobile applications. Adaptive inter/intra-frame prediction is an extension of JPEG-LS, a state-of-the-art lossless still image compression standard. Based on the image statistics of the wavelet transform domains in successive frames, inter/intra frame adaptive prediction is applied to the appropriate wavelet transform domain. This adaptation offers superior compression performance. This is achieved with low computational cost and no increase in additional information. Experiments on digital cinema test sequences confirm the effectiveness of the proposed algorithm.
Three-dimensional face pose detection and tracking using monocular videos: tool and application.
Dornaika, Fadi; Raducanu, Bogdan
2009-08-01
Recently, we have proposed a real-time tracker that simultaneously tracks the 3-D head pose and facial actions in monocular video sequences that can be provided by low quality cameras. This paper has two main contributions. First, we propose an automatic 3-D face pose initialization scheme for the real-time tracker by adopting a 2-D face detector and an eigenface system. Second, we use the proposed methods-the initialization and tracking-for enhancing the human-machine interaction functionality of an AIBO robot. More precisely, we show how the orientation of the robot's camera (or any active vision system) can be controlled through the estimation of the user's head pose. Applications based on head-pose imitation such as telepresence, virtual reality, and video games can directly exploit the proposed techniques. Experiments on real videos confirm the robustness and usefulness of the proposed methods.
Early forest fire detection using principal component analysis of infrared video
NASA Astrophysics Data System (ADS)
Saghri, John A.; Radjabi, Ryan; Jacobs, John T.
2011-09-01
A land-based early forest fire detection scheme which exploits the infrared (IR) temporal signature of fire plume is described. Unlike common land-based and/or satellite-based techniques which rely on measurement and discrimination of fire plume directly from its infrared and/or visible reflectance imagery, this scheme is based on exploitation of fire plume temporal signature, i.e., temperature fluctuations over the observation period. The method is simple and relatively inexpensive to implement. The false alarm rate is expected to be lower that of the existing methods. Land-based infrared (IR) cameras are installed in a step-stare-mode configuration in potential fire-prone areas. The sequence of IR video frames from each camera is digitally processed to determine if there is a fire within camera's field of view (FOV). The process involves applying a principal component transformation (PCT) to each nonoverlapping sequence of video frames from the camera to produce a corresponding sequence of temporally-uncorrelated principal component (PC) images. Since pixels that form a fire plume exhibit statistically similar temporal variation (i.e., have a unique temporal signature), PCT conveniently renders the footprint/trace of the fire plume in low-order PC images. The PC image which best reveals the trace of the fire plume is then selected and spatially filtered via simple threshold and median filter operations to remove the background clutter, such as traces of moving tree branches due to wind.
Adaptive low-rank subspace learning with online optimization for robust visual tracking.
Liu, Risheng; Wang, Di; Han, Yuzhuo; Fan, Xin; Luo, Zhongxuan
2017-04-01
In recent years, sparse and low-rank models have been widely used to formulate appearance subspace for visual tracking. However, most existing methods only consider the sparsity or low-rankness of the coefficients, which is not sufficient enough for appearance subspace learning on complex video sequences. Moreover, as both the low-rank and the column sparse measures are tightly related to all the samples in the sequences, it is challenging to incrementally solve optimization problems with both nuclear norm and column sparse norm on sequentially obtained video data. To address above limitations, this paper develops a novel low-rank subspace learning with adaptive penalization (LSAP) framework for subspace based robust visual tracking. Different from previous work, which often simply decomposes observations as low-rank features and sparse errors, LSAP simultaneously learns the subspace basis, low-rank coefficients and column sparse errors to formulate appearance subspace. Within LSAP framework, we introduce a Hadamard production based regularization to incorporate rich generative/discriminative structure constraints to adaptively penalize the coefficients for subspace learning. It is shown that such adaptive penalization can significantly improve the robustness of LSAP on severely corrupted dataset. To utilize LSAP for online visual tracking, we also develop an efficient incremental optimization scheme for nuclear norm and column sparse norm minimizations. Experiments on 50 challenging video sequences demonstrate that our tracker outperforms other state-of-the-art methods. Copyright © 2017 Elsevier Ltd. All rights reserved.
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.
Video-rate scanning two-photon excitation fluorescence microscopy and ratio imaging with cameleons.
Fan, G Y; Fujisaki, H; Miyawaki, A; Tsay, R K; Tsien, R Y; Ellisman, M H
1999-01-01
A video-rate (30 frames/s) scanning two-photon excitation microscope has been successfully tested. The microscope, based on a Nikon RCM 8000, incorporates a femtosecond pulsed laser with wavelength tunable from 690 to 1050 nm, prechirper optics for laser pulse-width compression, resonant galvanometer for video-rate point scanning, and a pair of nonconfocal detectors for fast emission ratioing. An increase in fluorescent emission of 1.75-fold is consistently obtained with the use of the prechirper optics. The nonconfocal detectors provide another 2.25-fold increase in detection efficiency. Ratio imaging and optical sectioning can therefore be performed more efficiently without confocal optics. Faster frame rates, at 60, 120, and 240 frames/s, can be achieved with proportionally reduced scan lines per frame. Useful two-photon images can be acquired at video rate with a laser power as low as 2.7 mW at specimen with the genetically modified green fluorescent proteins. Preliminary results obtained using this system confirm that the yellow "cameleons" exhibit similar optical properties as under one-photon excitation conditions. Dynamic two-photon images of cardiac myocytes and ratio images of yellow cameleon-2.1, -3.1, and -3.1nu are also presented. PMID:10233058
Gupta, Puneet; Bhowmick, Brojeshwar; Pal, Arpan
2017-07-01
Camera-equipped devices are ubiquitous and proliferating in the day-to-day life. Accurate heart rate (HR) estimation from the face videos acquired from the low cost cameras in a non-contact manner, can be used in many real-world scenarios and hence, require rigorous exploration. This paper has presented an accurate and near real-time HR estimation system using these face videos. It is based on the phenomenon that the color and motion variations in the face video are closely related to the heart beat. The variations also contain the noise due to facial expressions, respiration, eye blinking and environmental factors which are handled by the proposed system. Neither Eulerian nor Lagrangian temporal signals can provide accurate HR in all the cases. The cases where Eulerian temporal signals perform spuriously are determined using a novel poorness measure and then both the Eulerian and Lagrangian temporal signals are employed for better HR estimation. Such a fusion is referred as serial fusion. Experimental results reveal that the error introduced in the proposed algorithm is 1.8±3.6 which is significantly lower than the existing well known systems.
Draft genome sequences of 64 swine associated LA-MRSA ST5 isolates from the USA
USDA-ARS?s Scientific Manuscript database
Methicillin resistant Staphylococcus aureus colonizes humans and other animals such as swine. LA-MRSA sequence type (ST) 5 isolates are a public concern due to their pathogenicity and ability to acquire mobile genetic elements. This report presents draft genome sequences for 64 LA-MRSA ST5 isolates ...
Event-Related Potential Correlates of Declarative and Non-Declarative Sequence Knowledge
ERIC Educational Resources Information Center
Ferdinand, Nicola K.; Runger, Dennis; Frensch, Peter A.; Mecklinger, Axel
2010-01-01
The goal of the present study was to demonstrate that declarative and non-declarative knowledge acquired in an incidental sequence learning task contributes differentially to memory retrieval and leads to dissociable ERP signatures in a recognition memory task. For this purpose, participants performed a sequence learning task and were classified…
Chavhan, Govind B; Babyn, Paul S; Vasanawala, Shreyas S
2013-05-01
Familiarity with basic sequence properties and their trade-offs is necessary for radiologists performing abdominal magnetic resonance (MR) imaging. Acquiring diagnostic-quality MR images in the pediatric abdomen is challenging due to motion, inability to breath hold, varying patient size, and artifacts. Motion-compensation techniques (eg, respiratory gating, signal averaging, suppression of signal from moving tissue, swapping phase- and frequency-encoding directions, use of faster sequences with breath holding, parallel imaging, and radial k-space filling) can improve image quality. Each of these techniques is more suitable for use with certain sequences and acquisition planes and in specific situations and age groups. Different T1- and T2-weighted sequences work better in different age groups and with differing acquisition planes and have specific advantages and disadvantages. Dynamic imaging should be performed differently in younger children than in older children. In younger children, the sequence and the timing of dynamic phases need to be adjusted. Different sequences work better in smaller children and in older children because of differing breath-holding ability, breathing patterns, field of view, and use of sedation. Hence, specific protocols should be maintained for younger children and older children. Combining longer-higher-resolution sequences and faster-lower-resolution sequences helps acquire diagnostic-quality images in a reasonable time. © RSNA, 2013.
NASA Astrophysics Data System (ADS)
He, Qiang; Schultz, Richard R.; Chu, Chee-Hung Henry
2008-04-01
The concept surrounding super-resolution image reconstruction is to recover a highly-resolved image from a series of low-resolution images via between-frame subpixel image registration. In this paper, we propose a novel and efficient super-resolution algorithm, and then apply it to the reconstruction of real video data captured by a small Unmanned Aircraft System (UAS). Small UAS aircraft generally have a wingspan of less than four meters, so that these vehicles and their payloads can be buffeted by even light winds, resulting in potentially unstable video. This algorithm is based on a coarse-to-fine strategy, in which a coarsely super-resolved image sequence is first built from the original video data by image registration and bi-cubic interpolation between a fixed reference frame and every additional frame. It is well known that the median filter is robust to outliers. If we calculate pixel-wise medians in the coarsely super-resolved image sequence, we can restore a refined super-resolved image. The primary advantage is that this is a noniterative algorithm, unlike traditional approaches based on highly-computational iterative algorithms. Experimental results show that our coarse-to-fine super-resolution algorithm is not only robust, but also very efficient. In comparison with five well-known super-resolution algorithms, namely the robust super-resolution algorithm, bi-cubic interpolation, projection onto convex sets (POCS), the Papoulis-Gerchberg algorithm, and the iterated back projection algorithm, our proposed algorithm gives both strong efficiency and robustness, as well as good visual performance. This is particularly useful for the application of super-resolution to UAS surveillance video, where real-time processing is highly desired.
Video Super-Resolution via Bidirectional Recurrent Convolutional Networks.
Huang, Yan; Wang, Wei; Wang, Liang
2018-04-01
Super resolving a low-resolution video, namely video super-resolution (SR), is usually handled by either single-image SR or multi-frame SR. Single-Image SR deals with each video frame independently, and ignores intrinsic temporal dependency of video frames which actually plays a very important role in video SR. Multi-Frame SR generally extracts motion information, e.g., optical flow, to model the temporal dependency, but often shows high computational cost. Considering that recurrent neural networks (RNNs) can model long-term temporal dependency of video sequences well, we propose a fully convolutional RNN named bidirectional recurrent convolutional network for efficient multi-frame SR. Different from vanilla RNNs, 1) the commonly-used full feedforward and recurrent connections are replaced with weight-sharing convolutional connections. So they can greatly reduce the large number of network parameters and well model the temporal dependency in a finer level, i.e., patch-based rather than frame-based, and 2) connections from input layers at previous timesteps to the current hidden layer are added by 3D feedforward convolutions, which aim to capture discriminate spatio-temporal patterns for short-term fast-varying motions in local adjacent frames. Due to the cheap convolutional operations, our model has a low computational complexity and runs orders of magnitude faster than other multi-frame SR methods. With the powerful temporal dependency modeling, our model can super resolve videos with complex motions and achieve well performance.
Direct three-dimensional ultrasound-to-video registration using photoacoustic markers
NASA Astrophysics Data System (ADS)
Cheng, Alexis; Kang, Jin U.; Taylor, Russell H.; Boctor, Emad M.
2013-06-01
Modern surgical procedures often have a fusion of video and other imaging modalities to provide the surgeon with information support. This requires interventional guidance equipment and surgical navigation systems to register different tools and devices together, such as stereoscopic endoscopes and ultrasound (US) transducers. In this work, the focus is specifically on the registration between these two devices. Electromagnetic and optical trackers are typically used to acquire this registration, but they have various drawbacks typically leading to target registration errors (TRE) of approximately 3 mm. We introduce photoacoustic markers for direct three-dimensional (3-D) US-to-video registration. The feasibility of this method was demonstrated on synthetic and ex vivo porcine liver, kidney, and fat phantoms with an air-coupled laser and a motorized 3-D US probe. The resulting TRE for each experiment ranged from 380 to 850 μm with standard deviations ranging from 150 to 450 μm. We also discuss a roadmap to bring this system into the surgical setting and possible challenges along the way.
The AAPM/RSNA physics tutorial for residents: digital fluoroscopy.
Pooley, R A; McKinney, J M; Miller, D A
2001-01-01
A digital fluoroscopy system is most commonly configured as a conventional fluoroscopy system (tube, table, image intensifier, video system) in which the analog video signal is converted to and stored as digital data. Other methods of acquiring the digital data (eg, digital or charge-coupled device video and flat-panel detectors) will become more prevalent in the future. Fundamental concepts related to digital imaging in general include binary numbers, pixels, and gray levels. Digital image data allow the convenient use of several image processing techniques including last image hold, gray-scale processing, temporal frame averaging, and edge enhancement. Real-time subtraction of digital fluoroscopic images after injection of contrast material has led to widespread use of digital subtraction angiography (DSA). Additional image processing techniques used with DSA include road mapping, image fade, mask pixel shift, frame summation, and vessel size measurement. Peripheral angiography performed with an automatic moving table allows imaging of the peripheral vasculature with a single contrast material injection.
Multi-frame super-resolution with quality self-assessment for retinal fundus videos.
Köhler, Thomas; Brost, Alexander; Mogalle, Katja; Zhang, Qianyi; Köhler, Christiane; Michelson, Georg; Hornegger, Joachim; Tornow, Ralf P
2014-01-01
This paper proposes a novel super-resolution framework to reconstruct high-resolution fundus images from multiple low-resolution video frames in retinal fundus imaging. Natural eye movements during an examination are used as a cue for super-resolution in a robust maximum a-posteriori scheme. In order to compensate heterogeneous illumination on the fundus, we integrate retrospective illumination correction for photometric registration to the underlying imaging model. Our method utilizes quality self-assessment to provide objective quality scores for reconstructed images as well as to select regularization parameters automatically. In our evaluation on real data acquired from six human subjects with a low-cost video camera, the proposed method achieved considerable enhancements of low-resolution frames and improved noise and sharpness characteristics by 74%. In terms of image analysis, we demonstrate the importance of our method for the improvement of automatic blood vessel segmentation as an example application, where the sensitivity was increased by 13% using super-resolution reconstruction.
Shaw, S L; Salmon, E D; Quatrano, R S
1995-12-01
In this report, we describe a relatively inexpensive method for acquiring, storing and processing light microscope images that combines the advantages of video technology with the powerful medium now termed digital photography. Digital photography refers to the recording of images as digital files that are stored, manipulated and displayed using a computer. This report details the use of a gated video-rate charge-coupled device (CCD) camera and a frame grabber board for capturing 256 gray-level digital images from the light microscope. This camera gives high-resolution bright-field, phase contrast and differential interference contrast (DIC) images but, also, with gated on-chip integration, has the capability to record low-light level fluorescent images. The basic components of the digital photography system are described, and examples are presented of fluorescence and bright-field micrographs. Digital processing of images to remove noise, to enhance contrast and to prepare figures for printing is discussed.
Automatic colonic lesion detection and tracking in endoscopic videos
NASA Astrophysics Data System (ADS)
Li, Wenjing; Gustafsson, Ulf; A-Rahim, Yoursif
2011-03-01
The biology of colorectal cancer offers an opportunity for both early detection and prevention. Compared with other imaging modalities, optical colonoscopy is the procedure of choice for simultaneous detection and removal of colonic polyps. Computer assisted screening makes it possible to assist physicians and potentially improve the accuracy of the diagnostic decision during the exam. This paper presents an unsupervised method to detect and track colonic lesions in endoscopic videos. The aim of the lesion screening and tracking is to facilitate detection of polyps and abnormal mucosa in real time as the physician is performing the procedure. For colonic lesion detection, the conventional marker controlled watershed based segmentation is used to segment the colonic lesions, followed by an adaptive ellipse fitting strategy to further validate the shape. For colonic lesion tracking, a mean shift tracker with background modeling is used to track the target region from the detection phase. The approach has been tested on colonoscopy videos acquired during regular colonoscopic procedures and demonstrated promising results.
a Cloud-Based Architecture for Smart Video Surveillance
NASA Astrophysics Data System (ADS)
Valentín, L.; Serrano, S. A.; Oves García, R.; Andrade, A.; Palacios-Alonso, M. A.; Sucar, L. Enrique
2017-09-01
Turning a city into a smart city has attracted considerable attention. A smart city can be seen as a city that uses digital technology not only to improve the quality of people's life, but also, to have a positive impact in the environment and, at the same time, offer efficient and easy-to-use services. A fundamental aspect to be considered in a smart city is people's safety and welfare, therefore, having a good security system becomes a necessity, because it allows us to detect and identify potential risk situations, and then take appropriate decisions to help people or even prevent criminal acts. In this paper we present an architecture for automated video surveillance based on the cloud computing schema capable of acquiring a video stream from a set of cameras connected to the network, process that information, detect, label and highlight security-relevant events automatically, store the information and provide situational awareness in order to minimize response time to take the appropriate action.
Gleich, Tobias; Lorenz, Robert C; Gallinat, Jürgen; Kühn, Simone
2017-05-15
In the present longitudinal study, we aimed to investigate video game training associated neuronal changes in reward processing using functional magnetic resonance imaging (fMRI). We recruited 48 healthy young participants which were assigned to one of 2 groups: A group in which participants were instructed to play a commercial video game ("Super Mario 64 DS") on a portable Nintendo DS handheld console at least 30minutes a day over a period of two months (video gaming group; VG) or to a matched passive control group (CG). Before and after the training phase, in both groups, fMRI imaging was conducted during passively viewing reward and punishment-related videos sequences recorded from the trained video game. The results show that video game training may lead to reward related decrease in neuronal activation in the dorsolateral prefrontal cortex (DLPFC) and increase in the hippocampus. Additionally, the decrease in DLPFC activation was associated with gaming related parameters experienced during playing. Specifically, we found that in the VG, gaming related parameters like performance, experienced fun and frustration (assessed during the training period) were correlated to decrease in reward related DLPFC activity. Thus, neuronal changes in terms of video game training seem to be highly related to the appetitive character and reinforcement schedule of the game. Those neuronal changes may also be related to the often reported video game associated improvements in cognitive functions. Copyright © 2017 Elsevier Inc. All rights reserved.
McCamy, Michael B.; Otero-Millan, Jorge; Leigh, R. John; King, Susan A.; Schneider, Rosalyn M.; Macknik, Stephen L.; Martinez-Conde, Susana
2015-01-01
Human eyes move continuously, even during visual fixation. These “fixational eye movements” (FEMs) include microsaccades, intersaccadic drift and oculomotor tremor. Research in human FEMs has grown considerably in the last decade, facilitated by the manufacture of noninvasive, high-resolution/speed video-oculography eye trackers. Due to the small magnitude of FEMs, obtaining reliable data can be challenging, however, and depends critically on the sensitivity and precision of the eye tracking system. Yet, no study has conducted an in-depth comparison of human FEM recordings obtained with the search coil (considered the gold standard for measuring microsaccades and drift) and with contemporary, state-of-the art video trackers. Here we measured human microsaccades and drift simultaneously with the search coil and a popular state-of-the-art video tracker. We found that 95% of microsaccades detected with the search coil were also detected with the video tracker, and 95% of microsaccades detected with video tracking were also detected with the search coil, indicating substantial agreement between the two systems. Peak/mean velocities and main sequence slopes of microsaccades detected with video tracking were significantly higher than those of the same microsaccades detected with the search coil, however. Ocular drift was significantly correlated between the two systems, but drift speeds were higher with video tracking than with the search coil. Overall, our combined results suggest that contemporary video tracking now approaches the search coil for measuring FEMs. PMID:26035820
Biological function in the twilight zone of sequence conservation.
Ponting, Chris P
2017-08-16
Strong DNA conservation among divergent species is an indicator of enduring functionality. With weaker sequence conservation we enter a vast 'twilight zone' in which sequence subject to transient or lower constraint cannot be distinguished easily from neutrally evolving, non-functional sequence. Twilight zone functional sequence is illuminated instead by principles of selective constraint and positive selection using genomic data acquired from within a species' population. Application of these principles reveals that despite being biochemically active, most twilight zone sequence is not functional.
Exploiting semantics for sensor re-calibration in event detection systems
NASA Astrophysics Data System (ADS)
Vaisenberg, Ronen; Ji, Shengyue; Hore, Bijit; Mehrotra, Sharad; Venkatasubramanian, Nalini
2008-01-01
Event detection from a video stream is becoming an important and challenging task in surveillance and sentient systems. While computer vision has been extensively studied to solve different kinds of detection problems over time, it is still a hard problem and even in a controlled environment only simple events can be detected with a high degree of accuracy. Instead of struggling to improve event detection using image processing only, we bring in semantics to direct traditional image processing. Semantics are the underlying facts that hide beneath video frames, which can not be "seen" directly by image processing. In this work we demonstrate that time sequence semantics can be exploited to guide unsupervised re-calibration of the event detection system. We present an instantiation of our ideas by using an appliance as an example--Coffee Pot level detection based on video data--to show that semantics can guide the re-calibration of the detection model. This work exploits time sequence semantics to detect when re-calibration is required to automatically relearn a new detection model for the newly evolved system state and to resume monitoring with a higher rate of accuracy.
Advances in Measurement of Skin Friction in Airflow
NASA Technical Reports Server (NTRS)
Brown, James L.; Naughton, Jonathan W.
2006-01-01
The surface interferometric skin-friction (SISF) measurement system is an instrument for determining the distribution of surface shear stress (skin friction) on a wind-tunnel model. The SISF system utilizes the established oil-film interference method, along with advanced image-data-processing techniques and mathematical models that express the relationship between interferograms and skin friction, to determine the distribution of skin friction over an observed region of the surface of a model during a single wind-tunnel test. In the oil-film interference method, a wind-tunnel model is coated with a thin film of oil of known viscosity and is illuminated with quasi-monochromatic, collimated light, typically from a mercury lamp. The light reflected from the outer surface of the oil film interferes with the light reflected from the oil-covered surface of the model. In the present version of the oil-film interference method, a camera captures an image of the illuminated model and the image in the camera is modulated by the interference pattern. The interference pattern depends on the oil-thickness distribution on the observed surface, and this distribution can be extracted through analysis of the image acquired by the camera. The oil-film technique is augmented by a tracer technique for observing the streamline pattern. To make the streamlines visible, small dots of fluorescentchalk/oil mixture are placed on the model just before a test. During the test, the chalk particles are embedded in the oil flow and produce chalk streaks that mark the streamlines. The instantaneous rate of thinning of the oil film at a given position on the surface of the model can be expressed as a function of the instantaneous thickness, the skin-friction distribution on the surface, and the streamline pattern on the surface; the functional relationship is expressed by a mathematical model that is nonlinear in the oil-film thickness and is known simply as the thin-oil-film equation. From the image data acquired as described, the time-dependent oil-thickness distribution and streamline pattern are extracted and by inversion of the thin-oil-film equation it is then possible to determine the skin-friction distribution. In addition to a quasi-monochromatic light source, the SISF system includes a beam splitter and two video cameras equipped with filters for observing the same area on a model in different wavelength ranges, plus a frame grabber and a computer for digitizing the video images and processing the image data. One video camera acquires the interference pattern in a narrow wavelength range of the quasi-monochromatic source. The other video camera acquires the streamline image of fluorescence from the chalk in a nearby but wider wavelength range. The interference- pattern and fluorescence images are digitized, and the resulting data are processed by an algorithm that inverts the thin-oil-film equation to find the skin-friction distribution.
NASA Astrophysics Data System (ADS)
Murillo, Sergio; Pattichis, Marios; Soliz, Peter; Barriga, Simon; Loizou, C. P.; Pattichis, C. S.
2010-03-01
Motion estimation from digital video is an ill-posed problem that requires a regularization approach. Regularization introduces a smoothness constraint that can reduce the resolution of the velocity estimates. The problem is further complicated for ultrasound videos (US), where speckle noise levels can be significant. Motion estimation using optical flow models requires the modification of several parameters to satisfy the optical flow constraint as well as the level of imposed smoothness. Furthermore, except in simulations or mostly unrealistic cases, there is no ground truth to use for validating the velocity estimates. This problem is present in all real video sequences that are used as input to motion estimation algorithms. It is also an open problem in biomedical applications like motion analysis of US of carotid artery (CA) plaques. In this paper, we study the problem of obtaining reliable ultrasound video motion estimates for atherosclerotic plaques for use in clinical diagnosis. A global optimization framework for motion parameter optimization is presented. This framework uses actual carotid artery motions to provide optimal parameter values for a variety of motions and is tested on ten different US videos using two different motion estimation techniques.
Adaptive format conversion for scalable video coding
NASA Astrophysics Data System (ADS)
Wan, Wade K.; Lim, Jae S.
2001-12-01
The enhancement layer in many scalable coding algorithms is composed of residual coding information. There is another type of information that can be transmitted instead of (or in addition to) residual coding. Since the encoder has access to the original sequence, it can utilize adaptive format conversion (AFC) to generate the enhancement layer and transmit the different format conversion methods as enhancement data. This paper investigates the use of adaptive format conversion information as enhancement data in scalable video coding. Experimental results are shown for a wide range of base layer qualities and enhancement bitrates to determine when AFC can improve video scalability. Since the parameters needed for AFC are small compared to residual coding, AFC can provide video scalability at low enhancement layer bitrates that are not possible with residual coding. In addition, AFC can also be used in addition to residual coding to improve video scalability at higher enhancement layer bitrates. Adaptive format conversion has not been studied in detail, but many scalable applications may benefit from it. An example of an application that AFC is well-suited for is the migration path for digital television where AFC can provide immediate video scalability as well as assist future migrations.
Video quality assessment method motivated by human visual perception
NASA Astrophysics Data System (ADS)
He, Meiling; Jiang, Gangyi; Yu, Mei; Song, Yang; Peng, Zongju; Shao, Feng
2016-11-01
Research on video quality assessment (VQA) plays a crucial role in improving the efficiency of video coding and the performance of video processing. It is well acknowledged that the motion energy model generates motion energy responses in a middle temporal area by simulating the receptive field of neurons in V1 for the motion perception of the human visual system. Motivated by the biological evidence for the visual motion perception, a VQA method is proposed in this paper, which comprises the motion perception quality index and the spatial index. To be more specific, the motion energy model is applied to evaluate the temporal distortion severity of each frequency component generated from the difference of Gaussian filter bank, which produces the motion perception quality index, and the gradient similarity measure is used to evaluate the spatial distortion of the video sequence to get the spatial quality index. The experimental results of the LIVE, CSIQ, and IVP video databases demonstrate that the random forests regression technique trained by the generated quality indices is highly correspondent to human visual perception and has many significant improvements than comparable well-performing methods. The proposed method has higher consistency with subjective perception and higher generalization capability.
Analysis of Preoperative Airway Examination with the CMOS Video Rhino-laryngoscope.
Tsukamoto, Masanori; Hitosugi, Takashi; Yokoyama, Takeshi
2017-05-01
Endoscopy is one of the most useful clinical techniques in difficult airway management Comparing with the fibroptic endoscope, this compact device is easy to operate and can provide the clear image. In this study, we investigated its usefulness in the preoperative examination of endoscopy. Patients undergoing oral maxillofacial surgery were enrolled in this study. We performed preoperative airway examination by electronic endoscope (The CMOS video rhino-laryngoscope, KARL STORZ Endoscopy Japan, Tokyo). The system is composed of a videoendoscope, a compact video processor and a video recorder. In addition, the endoscope has a small color charge coupled device (CMOS) chip built into the tip of the endoscope. The outer diameter of the tip of this scope is 3.7 mm. In this study, electronic endoscope was used for preoperative airway examination in 7 patients. The preoperative airway examination with electronic endoscope was performed successfully in all the patients except one patient The patient had the symptoms such as nausea and vomiting at the examination. We could perform preoperative airway examination with excellent visualization and convenient recording of video sequence images with the CMOS video rhino-laryngoscope. It might be a especially useful device for the patients of difficult airways.
Video redaction: a survey and comparison of enabling technologies
NASA Astrophysics Data System (ADS)
Sah, Shagan; Shringi, Ameya; Ptucha, Raymond; Burry, Aaron; Loce, Robert
2017-09-01
With the prevalence of video recordings from smart phones, dash cams, body cams, and conventional surveillance cameras, privacy protection has become a major concern, especially in light of legislation such as the Freedom of Information Act. Video redaction is used to obfuscate sensitive and personally identifiable information. Today's typical workflow involves simple detection, tracking, and manual intervention. Automated methods rely on accurate detection mechanisms being paired with robust tracking methods across the video sequence to ensure the redaction of all sensitive information while minimizing spurious obfuscations. Recent studies have explored the use of convolution neural networks and recurrent neural networks for object detection and tracking. The present paper reviews the redaction problem and compares a few state-of-the-art detection, tracking, and obfuscation methods as they relate to redaction. The comparison introduces an evaluation metric that is specific to video redaction performance. The metric can be evaluated in a manner that allows balancing the penalty for false negatives and false positives according to the needs of particular application, thereby assisting in the selection of component methods and their associated hyperparameters such that the redacted video has fewer frames that require manual review.
Spherical rotation orientation indication for HEVC and JEM coding of 360 degree video
NASA Astrophysics Data System (ADS)
Boyce, Jill; Xu, Qian
2017-09-01
Omnidirectional (or "360 degree") video, representing a panoramic view of a spherical 360° ×180° scene, can be encoded using conventional video compression standards, once it has been projection mapped to a 2D rectangular format. Equirectangular projection format is currently used for mapping 360 degree video to a rectangular representation for coding using HEVC/JEM. However, video in the top and bottom regions of the image, corresponding to the "north pole" and "south pole" of the spherical representation, is significantly warped. We propose to perform spherical rotation of the input video prior to HEVC/JEM encoding in order to improve the coding efficiency, and to signal parameters in a supplemental enhancement information (SEI) message that describe the inverse rotation process recommended to be applied following HEVC/JEM decoding, prior to display. Experiment results show that up to 17.8% bitrate gain (using the WS-PSNR end-to-end metric) can be achieved for the Chairlift sequence using HM16.15 and 11.9% gain using JEM6.0, and an average gain of 2.9% for HM16.15 and 2.2% for JEM6.0.
Patient-Physician Communication About Code Status Preferences: A Randomized Controlled Trial
Rhondali, Wadih; Perez-Cruz, Pedro; Hui, David; Chisholm, Gary B.; Dalal, Shalini; Baile, Walter; Chittenden, Eva; Bruera, Eduardo
2013-01-01
Purpose Code status discussions are important in cancer care. The best modality for such discussions has not been established. Our objective was to determine the impact of a physician ending a code status discussion with a question (autonomy approach) versus a recommendation (beneficence approach) on patients' do-not-resuscitate (DNR) preference. Methods Patients in a supportive care clinic watched two videos showing a physician-patient discussion regarding code status. Both videos were identical except for the ending: one ended with the physician asking for the patient's code status preference and the other with the physician recommending DNR. Patients were randomly assigned to watch the videos in different sequences. The main outcome was the proportion of patients choosing DNR for the video patient. Results 78 patients completed the study. 74% chose DNR after the question video, 73% after the recommendation video. Median physician compassion score was very high and not different for both videos. 30/30 patients who had chosen DNR for themselves and 30/48 patients who had not chosen DNR for themselves chose DNR for the video patient (100% v/s 62%). Age (OR=1.1/year) and white ethnicity (OR=9.43) predicted DNR choice for the video patient. Conclusion Ending DNR discussions with a question or a recommendation did not impact DNR choice or perception of physician compassion. Therefore, both approaches are clinically appropriate. All patients who chose DNR for themselves and most patients who did not choose DNR for themselves chose DNR for the video patient. Age and race predicted DNR choice. PMID:23564395
Real-time CT-video registration for continuous endoscopic guidance
NASA Astrophysics Data System (ADS)
Merritt, Scott A.; Rai, Lav; Higgins, William E.
2006-03-01
Previous research has shown that CT-image-based guidance could be useful for the bronchoscopic assessment of lung cancer. This research drew upon the registration of bronchoscopic video images to CT-based endoluminal renderings of the airway tree. The proposed methods either were restricted to discrete single-frame registration, which took several seconds to complete, or required non-real-time buffering and processing of video sequences. We have devised a fast 2D/3D image registration method that performs single-frame CT-Video registration in under 1/15th of a second. This allows the method to be used for real-time registration at full video frame rates without significantly altering the physician's behavior. The method achieves its speed through a gradient-based optimization method that allows most of the computation to be performed off-line. During live registration, the optimization iteratively steps toward the locally optimal viewpoint at which a CT-based endoluminal view is most similar to a current bronchoscopic video frame. After an initial registration to begin the process (generally done in the trachea for bronchoscopy), subsequent registrations are performed in real-time on each incoming video frame. As each new bronchoscopic video frame becomes available, the current optimization is initialized using the previous frame's optimization result, allowing continuous guidance to proceed without manual re-initialization. Tests were performed using both synthetic and pre-recorded bronchoscopic video. The results show that the method is robust to initialization errors, that registration accuracy is high, and that continuous registration can proceed on real-time video at >15 frames per sec. with minimal user-intervention.
Prediction of shot success for basketball free throws: visual search strategy.
Uchida, Yusuke; Mizuguchi, Nobuaki; Honda, Masaaki; Kanosue, Kazuyuki
2014-01-01
In ball games, players have to pay close attention to visual information in order to predict the movements of both the opponents and the ball. Previous studies have indicated that players primarily utilise cues concerning the ball and opponents' body motion. The information acquired must be effective for observing players to select the subsequent action. The present study evaluated the effects of changes in the video replay speed on the spatial visual search strategy and ability to predict free throw success. We compared eye movements made while observing a basketball free throw by novices and experienced basketball players. Correct response rates were close to chance (50%) at all video speeds for the novices. The correct response rate of experienced players was significantly above chance (and significantly above that of the novices) at the normal speed, but was not different from chance at both slow and fast speeds. Experienced players gazed more on the lower part of the player's body when viewing a normal speed video than the novices. The players likely detected critical visual information to predict shot success by properly moving their gaze according to the shooter's movements. This pattern did not change when the video speed was decreased, but changed when it was increased. These findings suggest that temporal information is important for predicting action outcomes and that such outcomes are sensitive to video speed.
Minimally invasive video-assisted thyroid surgery: how can we improve the learning curve?
Castagnola, G; Giulii Cappone, M; Tierno, S M; Mezzetti, G; Centanini, F; Vetrone, I; Bellotti, C
2012-10-01
Minimally invasive video-assisted thyroidectomy (MIVAT) is a technically demanding procedure and requires a surgical team skilled in both endocrine and endoscopic surgery. A time consuming learning and training period is mandatory at the beginning of the experience. The aim of our report is to focus some aspects of the learning curve of the surgeon who practices video-assisted thyroid procedures for the first time, through the analysis of our preliminary series of 36 cases. From September 2004 to April 2005 we selected 36 patients for minimally invasive video-assisted surgery of the thyroid. The patients were considered eligible if they presented with a nodule not exceeding 35 mm in maximum diameter; total thyroid volume within normal range; absence of biochemical and echographic signs of thyroiditis. We analyzed surgical results, conversion rate, operating time, post-operative complications, hospital stay, cosmetic outcome of the series. We performed 36 total thyroidectomy. The procedure was successfully carried out in 33/36 cases. Post-operative complications included 3 transient recurrent nerve palsies and 2 transient hypocalcemias; no definitive hypoparathyroidism was registered. All patients were discharged 2 days after operation. The cosmetic result was considered excellent by most patients. Advances in skills and technology have enabled surgeons to reproduce most open surgical techniques with video-assistance or laparoscopically. Training is essential to acquire any new surgical technique and it should be organized in detail to exploit it completely.
A Novel Method for Real-Time Audio Recording With Intraoperative Video.
Sugamoto, Yuji; Hamamoto, Yasuyoshi; Kimura, Masayuki; Fukunaga, Toru; Tasaki, Kentaro; Asai, Yo; Takeshita, Nobuyoshi; Maruyama, Tetsuro; Hosokawa, Takashi; Tamachi, Tomohide; Aoyama, Hiromichi; Matsubara, Hisahiro
2015-01-01
Although laparoscopic surgery has become widespread, effective and efficient education in laparoscopic surgery is difficult. Instructive laparoscopy videos with appropriate annotations are ideal for initial training in laparoscopic surgery; however, the method we use at our institution for creating laparoscopy videos with audio is not generalized, and there have been no detailed explanations of any such method. Our objectives were to demonstrate the feasibility of low-cost simple methods for recording surgical videos with audio and to perform a preliminary safety evaluation when obtaining these recordings during operations. We devised a method for the synchronous recording of surgical video with real-time audio in which we connected an amplifier and a wireless microphone to an existing endoscopy system and its equipped video-recording device. We tested this system in 209 cases of laparoscopic surgery in operating rooms between August 2010 and July 2011 and prospectively investigated the results of the audiovisual recording method and examined intraoperative problems. Numazu City Hospital in Numazu city, Japan. Surgeons, instrument nurses, and medical engineers. In all cases, the synchronous input of audio and video was possible. The recording system did not cause any inconvenience to the surgeon, assistants, instrument nurse, sterilized equipment, or electrical medical equipment. Statistically significant differences were not observed between the audiovisual group and control group regarding the operating time, which had been divided into 2 slots-performed by the instructors or by trainees (p > 0.05). This recording method is feasible and considerably safe while posing minimal difficulty in terms of technology, time, and expense. We recommend this method for both surgical trainees who wish to acquire surgical skills effectively and medical instructors who wish to teach surgical skills effectively. Copyright © 2015 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Static hand gesture recognition from a video
NASA Astrophysics Data System (ADS)
Rokade, Rajeshree S.; Doye, Dharmpal
2011-10-01
A sign language (also signed language) is a language which, instead of acoustically conveyed sound patterns, uses visually transmitted sign patterns to convey meaning- "simultaneously combining hand shapes, orientation and movement of the hands". Sign languages commonly develop in deaf communities, which can include interpreters, friends and families of deaf people as well as people who are deaf or hard of hearing themselves. In this paper, we proposed a novel system for recognition of static hand gestures from a video, based on Kohonen neural network. We proposed algorithm to separate out key frames, which include correct gestures from a video sequence. We segment, hand images from complex and non uniform background. Features are extracted by applying Kohonen on key frames and recognition is done.
Study of Temporal Effects on Subjective Video Quality of Experience.
Bampis, Christos George; Zhi Li; Moorthy, Anush Krishna; Katsavounidis, Ioannis; Aaron, Anne; Bovik, Alan Conrad
2017-11-01
HTTP adaptive streaming is being increasingly deployed by network content providers, such as Netflix and YouTube. By dividing video content into data chunks encoded at different bitrates, a client is able to request the appropriate bitrate for the segment to be played next based on the estimated network conditions. However, this can introduce a number of impairments, including compression artifacts and rebuffering events, which can severely impact an end-user's quality of experience (QoE). We have recently created a new video quality database, which simulates a typical video streaming application, using long video sequences and interesting Netflix content. Going beyond previous efforts, the new database contains highly diverse and contemporary content, and it includes the subjective opinions of a sizable number of human subjects regarding the effects on QoE of both rebuffering and compression distortions. We observed that rebuffering is always obvious and unpleasant to subjects, while bitrate changes may be less obvious due to content-related dependencies. Transient bitrate drops were preferable over rebuffering only on low complexity video content, while consistently low bitrates were poorly tolerated. We evaluated different objective video quality assessment algorithms on our database and found that objective video quality models are unreliable for QoE prediction on videos suffering from both rebuffering events and bitrate changes. This implies the need for more general QoE models that take into account objective quality models, rebuffering-aware information, and memory. The publicly available video content as well as metadata for all of the videos in the new database can be found at http://live.ece.utexas.edu/research/LIVE_NFLXStudy/nflx_index.html.
NASA Astrophysics Data System (ADS)
Wu, Kaizhi; Zhang, Xuming; Chen, Guangxie; Weng, Fei; Ding, Mingyue
2013-10-01
Images acquired in free breathing using contrast enhanced ultrasound exhibit a periodic motion that needs to be compensated for if a further accurate quantification of the hepatic perfusion analysis is to be executed. In this work, we present an algorithm to compensate the respiratory motion by effectively combining the PCA (Principal Component Analysis) method and block matching method. The respiratory kinetics of the ultrasound hepatic perfusion image sequences was firstly extracted using the PCA method. Then, the optimal phase of the obtained respiratory kinetics was detected after normalizing the motion amplitude and determining the image subsequences of the original image sequences. The image subsequences were registered by the block matching method using cross-correlation as the similarity. Finally, the motion-compensated contrast images can be acquired by using the position mapping and the algorithm was evaluated by comparing the TICs extracted from the original image sequences and compensated image subsequences. Quantitative comparisons demonstrated that the average fitting error estimated of ROIs (region of interest) was reduced from 10.9278 +/- 6.2756 to 5.1644 +/- 3.3431 after compensating.