Showing papers on "Inter frame published in 2012"

A Colon Video Analysis Framework for Polyp Detection

Abstract: This paper presents an automated video analysis framework for the detection of colonic polyps in optical colonoscopy. Our proposed framework departs from previous methods in that we include spatial frame-based analysis and temporal video analysis using time-course image sequences. We also provide a video quality assessment scheme including two measures of frame quality. We extract colon-specific anatomical features from different image regions using a windowing approach for intraframe spatial analysis. Anatomical features are described using an eigentissue model. We apply a conditional random field to model interframe dependences in tissue types and handle variations in imaging conditions and modalities. We validate our method by comparing our polyp detection results to colonoscopy reports from physicians. Our method displays promising preliminary results and shows strong invariance when applied to both white light and narrow-band video. Our proposed video analysis system can provide objective diagnostic support to physicians by locating polyps during colon cancer screening exams. Furthermore, our system can be used as a cost-effective video annotation solution for the large backlog of existing colonoscopy videos.

A novel video inter-frame forgery model detection scheme based on optical flow consistency

Abstract: In this paper, a novel video inter-frame forgery detection scheme based on optical flow consistency is proposed. It is based on the finding that inter-frame forgery will disturb the optical flow consistency. This paper noticed the subtle difference between frame insertion and deletion, and proposed different detection schemes for them. A window based rough detection method and binary searching scheme are proposed to detect frame insertion forgery. Frame-to-frame optical flows and double adaptive thresholds are applied to detect frame deletion forgery. This paper not only detects video forgery, but also identifies the forgery model. Experiments show that our scheme achieves a good performance in identifying frame insertion and deletion model.

Multiple Hypotheses Bayesian Frame Rate Up-Conversion by Adaptive Fusion of Motion-Compensated Interpolations

Abstract: Frame rate up-conversion (FRUC) improves the viewing experience of a video because the motion in a FRUC-constructed high frame-rate video looks more smooth and continuous. This paper proposes a multiple hypotheses Bayesian FRUC scheme for estimating the intermediate frame with maximum a posteriori probability, in which both temporal motion model and spatial image model are incorporated into the optimization criterion. The image model describes the spatial structure of neighboring pixels while the motion model describes the temporal correlation of pixels along motion trajectories. Instead of employing a single uniquely optimal motion, multiple “optimal” motion trajectories are utilized to form a group of motion hypotheses. To obtain accurate estimation for the pixels in missing intermediate frames, the motion-compensated interpolations generated by all these motion hypotheses are adaptively fused according to the reliability of each hypothesis. We revealed by numerical analysis that this reliability (i.e., the variance of interpolation errors along the hypothesized motion trajectory) can be measured by the variation of reference pixels along the motion trajectory. To obtain the multiple motion fields, a set of block-matching sizes is used and the motion fields are estimated by progressively reducing the size of matching block. Experimental results show that the proposed method can significantly improve both the objective and the subjective quality of the constructed high frame rate video.

Method and device for encoding a depth map of multi viewpoint video data, and method and device for decoding the encoded depth map

Abstract: A method and apparatus for decoding the depth map of multi-view video data are provided. The method includes splitting a block of restored multi-view color video frame into a partition based on a pixel value of the block of the prediction-encoded and restored multi-view color video frame; obtaining a parameter indicating correlation between block partitions of the multi-view color video frame and block partitions of the depth map frame using peripheral pixel values of the block partitions of the multi-view color video frame and peripheral pixel values of the block partitions of the depth map frame corresponding to the block partitions of the multi-view color video frame with respect to each of the block partitions of the restored multi-view color video frame; and obtaining prediction values of corresponding block partitions of the depth map frame from the block partitions of the restored multi-view color video frame using the obtained parameter.

Reduced-Reference Video Quality Assessment of Compressed Video Sequences

Abstract: In this paper, a novel reduced-reference (RR) video quality assessment (VQA) is proposed by exploiting the spatial information loss and the temporal statistical characteristics of the interframe histogram. From the spatial perspective, an energy variation descriptor (EVD) is proposed to measure the energy change of each individual encoded frame, which results from the quantization process. Besides depicting the energy change, EVD can further simulate the texture masking property of the human visual system (HVS). From the temporal perspective, the generalized Gaussian density (GGD) function is employed to capture the natural statistics of the interframe histogram distribution. The city-block distance (CBD) is used to calculate the histogram distance between the original video sequence and the encoded one. For simplicity, the difference image between adjacent frames is employed to characterize the temporal interframe relationship. By combining the spatial EVD together with the temporal CBD, an efficient RR VQA is developed. Evaluation on the subjective quality video database demonstrates that the proposed method outperforms the representative RR video quality metric and the full-reference VQAs, such as peak signal-to-noise ratio and structure similarity index in matching subjective ratings. This means that the proposed metric is more consistent with the HVS perception. Furthermore, as only a small number of RR features are extracted for representing the original video sequence (each frame requires only one parameter for describing EVD and three parameters for recording GGD), the RR features can be embedded into the video sequences or transmitted through the ancillary data channel, which can be used in the video quality monitoring system.

WaveCast: Wavelet based wireless video broadcast using lossy transmission

Abstract: Wireless video broadcasting is a popular application of mobile network. However, the traditional approaches have limited supports to the accommodation of users with diverse channel conditions. The newly emerged Softcast approach provides smooth multicast performance but is not very efficient in inter frame compression. In this work, we propose a new video multicast approach: WaveCast. Different from softcast, WaveCast utilizes motion compensated temporal filter (MCTF) to exploit inter frame redundancy, and utilizes conventional framework to transmit motion information such that the MVs can be reconstructed losslessly. Meanwhile, WaveCast transmits the transform coefficients in lossy mode and performs gracefully in multicast. In experiments, Wave-Cast outperforms softcast 2dB in video PSNR at low channel SNR, and outperforms H.264 based framework up to 8dB in broadcast.

Distributed Soft Video Broadcast (DCAST) with Explicit Motion

Abstract: Video broadcasting is a popular application of wireless network. However, the existing layered approaches can hardly accommodate users with diverse channel conditions as analog communication can do. The newly emerged `soft cast' approach, utilizing soft broadcast, provides smooth multicast performance but is not very efficient in inter frame compression. In this work, we propose a motion-aligned wireless video multicast scheme DCAST. Instead of using conventional close loop prediction (CLP), DCAST is based on distributed source coding (DSC) theory. This helps DCAST to avoid error propagation but still achieve high compression efficiency in inter frame coding. DCAST outperforms soft cast 5dB in video PSNR while maintaining the similar graceful degradation feature as soft cast.

Quadtree Based Nonsquare Block Structure for Inter Frame Coding in High Efficiency Video Coding

Abstract: A concept of a quadtree based nonsquare block coding structure is presented in this paper for the emerging High Efficiency Video Coding standard, which includes a quadtree based asymmetric motion partitioning scheme and a nonsquare quadtree transform (NSQT) algorithm. Nonsquare motion partitioning in inter frame coding provides the possibility of getting more accurate prediction results by splitting one coding block into two nonsquare prediction blocks. Contrary to the traditional symmetric motion partitions (SMP), asymmetric motion partitions (AMP) are proposed to improve the coding efficiency, especially for the coding blocks with irregular object boundaries. NSQT is designed for nonsquare prediction blocks (SMP and AMP), which combines square and nonsquare transform blocks in a unified transform structure. It exploits the directional characteristic of an image block to improve the transform efficiency. The combination of nonsquare partitions and NSQT provides high coding flexibility and low implementation cost for both encoder and decoder design. Simulation results show that about 0.9%-2.8% bit-rate saving can be achieved in terms of different configurations, and subjective quality can also be improved.

Method of analysing a video of sports motion

Abstract: The invention is directed to a method, apparatus, system and computer program product for analysing video images of a sports motion and, in particular, to identification of key motion positions within a video and automatic extraction of segments of a video containing a sports motion. Video data displaying a sports motion comprises data representative of a number of image frames. For a number of image frames, one or more frame difference measures are calculated between the image frame and another image frame. The frame difference measures are analysed to identify a plurality of image frames that each show a key position of the sports motion. The segment of the video containing the sports motion showing the sports motion is between two of the image frames showing the key positions. Frame difference measures may be calculated based on pixel difference measures or optical flow techniques.

Video encoding and decoding

Abstract: A temporal motion vector predictor is includable, together with one or more spatial motion vector predictors, in a set of motion vector predictors for a block to encode of a current frame. A method of determining the temporal motion vector predictor comprises selecting as the temporal predictor one motion vector from among motion vectors in a reference block of a reference frame different from the current frame. The reference block is a block of the reference frame collocated with the block to encode or a block of the reference frame neighboring the collocated block. The selection is based on a diversity criterion for achieving diversity among the predictors of the set. This can reduce the motion vector memory requirements with no or no significant additional coding efficiency penalty. Alternatively, even if the motion vector memory is not reduced in size, coding efficiency improvements can be achieved.

Inter-frame complex oct data analysis techniques

Abstract: Techniques for collecting and processing complex OCT data to detect localized motion contrast information with enhanced accuracy and sensitivity are presented. In a preferred embodiment, vector differences between complex OCT signals taken at the same location on the sample are used to detect blood flow in the retina. Additional embodiments involving non-linear intensity weighting of the motion contrast information, normalization of the vector difference amplitudes, and calculating the absolute value of the standard deviation of Doppler signal are described. Image processing techniques to enhance the images resulting from these motion contrast techniques are also presented.

MOTION VECTOR PREDICTORS (MVPs) FOR BI-PREDICTIVE INTER MODE IN VIDEO CODING

Abstract: This disclosure describes video coding techniques applicable to a bipredictive intermode that uses adaptive motion vector prediction (AMVP). In particular, this disclosure describes techniques for encoding or decoding video data in which AMVP is used to code a first motion vector and a second motion vector associated with a current video block that is coded in the bipredictive inter mode. More specifically, this disclosure describes techniques in which one motion vector of a bipredictive video block can be used to define a candidate motion vector predictor (MVP) for predicting another motion vector of the bipredictive video block. In many examples, a scaled version of the first motion vector of the bipredictive video block is used as the MVP for the second motion vector of the bipredictive video block. By defining an additional MVP candidate for the second motion vector of a bipredictive video block, improved compression may be achieved.

Controlling a video content system

Abstract: According to examples of the presently disclosed subject matter, a method of controlling a video content system can include: obtaining a current input frame and a preceding input frame from an input video sequence and obtaining a current degraded frame and a preceding degraded frame from a degraded video sequence corresponding to the input video sequence; computing a first differences value from the current input and the preceding input frames and a second differences value from the current degraded frame and the preceding degraded frame, comparing the first and second differences values, giving rise to an inter-frame quality score; computing an intra-frame quality score using an intra-frame quality measure that is applied in the pixel-domain of the current degraded frame and the current input frame and providing a configuration instruction to the video content system based on a quality criterion related to the inter-frame and the intra-frame quality scores.

Efficient Frame Concealment for Depth Image-Based 3-D Video Transmission

Abstract: In depth image-based 3-D video transmission, the compressed video stream is very likely to be corrupted by channel errors. Due to the high compression ratio of H.264/AVC, it is often common that an entire coded picture is packetized into one packet. Thus the loss of a packet may result in the loss of the whole video frame. Currently, most of the frame concealment methods are mainly for 2-D video transmission. In this paper, we have proposed an efficient frame concealment algorithm for depth image-based 3-D video transmission, which is able to provide accurate estimation for the motion vectors of the lost frame with the help of the depth information. Simulation results show that it is highly effective and significantly outperforms other existing frame recovery methods by up to 2.91 dB.

Keyframe Based Video Summarization Using Automatic Threshold & Edge Matching Rate

Abstract: Shot boundary detection and Keyframe Extraction is a fundamental step for organization of large video data. Key frame extraction has been recognized as one of the important research issues in video information retrieval. Video shot boundary detection, which segments a video by detecting boundaries between camera shots, is usually the first and important step for content based video retrieval and video summarization. This paper discusses the importance of key frame extraction; briefly review and evaluate the existing approaches, to overcome the shortcomings of the existing approaches. This paper also proposes a new approach for key frame extraction based on the block based Histogram difference and edge matching rate. Firstly, the Histogram difference of every frame is calculated, and then the edges of the candidate key frames are extracted by Prewitt operator. At last, the edges of adjacent frames are matched. If the edge matching rate is above average edge matching rate, the current frame is deemed to the redundant key frame and should be discarded. Histogram based algorithms are very applicable to SBD; They provide global information about the video content and are faster without any performance degradations.

Techniques to perform fast motion estimation

Abstract: Techniques to perform fast motion estimation are described An apparatus may comprise a motion estimator operative to receive as input a current frame and a reference frame from a digital video sequence The motion estimator may generate and output a motion vector The motion vector may represent a change in position between a current block of the current frame and a matching reference block of the reference frame The motion estimator may utilize an enhanced block matching technique to perform block matching based on stationary and spatially proximate blocks Other embodiments are described and claimed

Video inter-frame compression coding method based on macroblock features and statistical properties

Abstract: The invention discloses a video inter-frame compression coding method based on macroblock features and statistical properties and relates to the field of video compression coding. The method comprises the following steps: firstly extracting brightness information of the current coding macroblock from original video data, adopting the dual-layer prejudgment criteria for determining the optimal inter-frame coding mode according to the statistical properties of the optimal inter-frame mode selected by the current coding macroblock, further utilizing the time-space relevant features of the current coding macroblock for selectively carrying out intra-frame coding, comparing the optimal inter-frame coding mode with the optimal intra-frame coding mode according to a rate distortion cost function, determining the final inter-frame coding mode and coding the current macroblock. Compared with the ergodic full-search inter-frame predictive coding method adopted in video coding standard H.264, the method has almost no loss of video quality, strictly controls the increase of code rate, keeps the excellent performance of high compression ratio of the original standard algorithm and can greatly improve the inter-frame coding speed.

Key frame extraction of online video based on optimized frame difference

Abstract: Key frame extraction is a basic technology of online video retrieval and abstract establishing. Efficient key frame extraction technology can promote the development of widely-used video browsing technology. In this paper, we first reviewed some commonly-used key frame extraction technology, and then proposed a key frame extraction technology based on optimized frame difference, which measures the similarity of two adjacent frames' contents in terms of the information of frame difference, and extracts key frames after optimizing the frame difference. The experiment results show that the proposed algorithm can extract key information of online video efficiently, and has a good description in the aspect of changes in the movement of the lens.

Early termination of coding unit splitting for HEVC

Abstract: The emerging high-efficiency video coding (HEVC) standard employs a new coding structure characterized by coding unit (CU), prediction unit (PU) and transform unit (TU) It improves the coding efficiency significantly, but also introduces great computation complexity on the decision of optimal CU, PU and TU sizes To reduce the encoding complexity, we propose a CU splitting early termination scheme for inter frame coding In the proposed scheme, the characteristics of prediction residuals are utilized to early terminate the CU splitting Specifically, the Mean Square Error (MSE) between the prediction block and the origin block for each CU level is obtained and then compared with an adaptive threshold The recursive CU splitting process is early terminated according to the threshold Experimental results demonstrate that, the proposed algorithm achieves up to 3483% total encoding time reduction with less than 025% BD-rate increase on average

Adaptive bitrate management on progressive download with indexed media files

Abstract: A method includes receiving streaming media data having an original media frame and an original frame index referencing the original media frame; determining an optimal session bitrate, wherein the optimal session bitrate is based on the available network bandwidth between a server and a terminal; allocating a frame budget for an output media frame by estimating a frame size of the output media frame based on the original frame index and the optimal session bitrate; generating the output media frame by processing the original media frame based on first encoding parameters and, if the allocated frame budget is greater than a frame size of the processed media frame, padding the processed media frame; and providing the output media frame.

Multiview video data encoding method and device, and decoding method and device

Abstract: Disclosed are a multiview video data encoding method and device and decoding method and device. A multiview video data encoding method according to one embodiment of the present invention acquires a multiview colour video frame and a depth map frame which corresponds to the multiview colour video frame, prediction encodes the acquired multiview colour video frame, and, using the encoding result of the prediction encoded multiview colour video frame, prediction encodes the corresponding depth map frame.

Method, computer program product, and system for multi-threaded video encoding

Abstract: A method, computer program product, and system are provided for multi-threaded video encoding. The method includes the steps of generating a set of motion vectors in a hardware video encoder based on a current frame of a video stream and a reference frame of the video stream, dividing the current frame into a number of slices, encoding each slice of the current frame based on the set of motion vectors, and combining the encoded slices to generate an encoded bitstream.

News video scene generating method

Abstract: The invention discloses a news video scene generating method which comprises the following steps: firstly sampling a news video sequence according to a preset interval; calculating the similarity of color histograms of two adjacent video image frames according to the color histogram of a sampled video image; determining a shot boundary sequence according to interframe similarity, the preset high threshold value, the preset low threshold value and the preset lowest threshold value of length of a dissolve shot of the whole news video sequence; then judging with a flashlight; selecting a first frame of each shot as a shot key frame and outputting a boundary sequence of the scene according to the similarity among shot key frames and a corner distribution figure in a subtitle area. With the adoption of the technical scheme, the problem that partitioning algorithm of the double threshold value shot is higher in complexity and the partitioning result is affected by the flashlight can be solved, and continuous shots with same subtitle and the similar visions can be merged to a same video scene when the video scene is generated.

System and method for adaptive frame re-compression in video processing system

Abstract: Method and system of video decoding incorporating frame compression to reduce frame buffer size are disclosed. The method adjusts parameters of the frame compression according to decoder system information or syntax element in the video bitstream. The decoder system information may be selected from a group consisting of system status, system parameter and a combination of system status and system parameter. The decoder system information may include system bandwidth, frame buffer size, frame buffer status, system power consumption, and system processing load. The syntax element comprises reference frame indicator, initial picture QP (quantization parameter), picture type, and picture size. The adaptive frame compression may be applied to adjust compression ratio. Furthermore, the adaptive frame compression may be applied to a decoder for a scalable video coding system or a multi-layer video coding system.

Effective Search Point Reduction Algorithm and its VLSI Design for HDTV H.264/AVC Variable Block Size Motion Estimation

Abstract: Variable block size motion estimation (VBSME) in H.264/AVC has greatly led to achieve an optimal inter frame encoding. However, the computation burden of the VBSME becomes the bottleneck of the H.264/AVC encoders. The conventional architecture in hardware realization is hard to adopt a fast software algorithm suitable to reduce the VBSME computation burden. Therefore, this paper presents a search point reduction (SPR) algorithm with an efficient hardware design, able to decrease the motion estimation time while maintaining the coding performance of H.264. The effectiveness of the proposed method is compared with those of existing methods with respect to chip area, operation frequency, and throughput rate. The proposed SPR algorithm increases the coding speed by around 90%; with a peak signal-to-noise ratio drop of less than 0.1 dB than that achieved by the JM reference software. The proposed SPR algorithm can operate at 200 MHz with 191 k gate count, which supports high-definition television 1280nn720 format.

Partial frame utilization in video codecs

Abstract: Embodiments of the present invention provide techniques for efficiently coding/decoding video data during circumstances where a decoder only requires or utilizes a portion of coded frames. A coder may exchange signaling with a decoder to identify unused areas of frames and prediction modes for the unused areas. An input frame may be parsed into a used area and an unused area based on the exchanged signaling. If motion vectors of the input frame are not limited to the used areas of the reference frames, the unused area of the input frame may be coded using low complexity. If the motion vectors of the input frame are limited to the used areas of the reference frames, the pixel blocks in the unused area of the input frame may not be coded, or the unused area of the input frame may be filled with gray, white, or black pixel blocks.

Automated tripod detection and handling in video stabilization

Abstract: An apparatus, method, and computer-readable medium for motion sensor-based video stabilization A motion sensor may capture motion data of a video sequence A controller may compute instantaneous motion of the camera for a current frame of the video sequence The controller may compare the instantaneous motion to a threshold value representing a still condition and reduce a video stabilization strength parameter for the current frame if the instantaneous motion is less than the threshold value A video stabilization unit may perform video stabilization on the current frame according to the frame's strength parameter

Method for detecting abnormal behavior during video monitoring

Abstract: The invention discloses a method for detecting an abnormal behavior during video monitoring. By using the current detection method, there is one single consideration factor and misinformation is easy to be generated. By using the method of the invention, the above problem can be solved. The method comprises the following steps: a. reading a video image frame and converting a video image into a grayscale image; b. detecting a motion object in the grayscale image; c. tracking the motion object, determining and analyzing the motion object; d. calculating and analyzing an interframe variation entropy value of the motion object and simultaneously carrying out motion object characteristic point extraction, calculating a motion speed and a direction of the each characteristic point and calculating motion energy of the motion object; e. according to the interframe variation entropy value of the motion object and the motion energy, carrying out a fighting decision, giving an alarm if there is a fight.

Motion compensation based on tangent distance prediction for video compression

Abstract: We present a new algorithm for motion compensation that uses a motion estimation method based on tangent distance. The method is compared with a Block-Matching based approach in various common situations. Whereas Block-Matching algorithms usually only predict positions of blocks over time, our method also predicts the evolution of pixels into these blocks. The prediction error is then drastically decreased. The method is implemented into the Theora codec proving that this algorithm improves the video codec performances. Highlights? Provides a new motion compensation algorithm for video compression. ? Compares offered method with classical block matching strategy. ? Improves compression rates on Theora codec.

Robust non-local regularization framework for motion compensated dynamic imaging without explicit motion estimation

Abstract: We introduce an regularized reconstruction scheme to recover dynamic imaging datasets with significant inter frame motion from undersampled Fourier data. The proposed nonlocal regularization penalty is an unweighted sum of distances between image patch pairs in the 3-D dataset. We use robust distance metrics to compute the distance between image patches; these metrics encourage the smoothing between similar patches, while discouraging the averaging of dissimilar patches. Hence, this algorithm is capable of exploiting the similarities between patch pairs in adjacent frames even when they are well separated due to motion, eventhough it does not perform explicit motion estimation. Unlike current non-local regularization schemes, the proposed penalty does not need good initial guesses to estimate the weights. Hence, this approach is readily applicable to accelerated dynamic imaging problems, where good initial guesses are challenging to obtain. The validation of the proposed scheme on numerical phantoms and dynamic MRI datasets demonstrate the superior performance of the proposed scheme over current dynamic imaging schemes.