The Experts below are selected from a list of 1956 Experts worldwide ranked by ideXlab platform

Bernd Girod - One of the best experts on this subject based on the ideXlab platform.

  • background extraction and long term memory Motion Compensated Prediction for spatial random access enabled video coding
    Picture Coding Symposium, 2009
    Co-Authors: Aditya Mavlankar, Bernd Girod
    Abstract:

    Video streaming with virtual pan/tilt/zoom functionality allows the viewer to watch arbitrary regions of a high-spatial-resolution scene. A video coding scheme with random access to arbitrary regions of arbitrary zoom factors helps avoid transmission and/or decoding of the entire high-spatial-resolution video signal. The video coding scheme, proposed in our earlier work, creates a multi-resolution representation and uses P slices of H.264/AVC. The base layer, which provides a thumbnail overview of the entire scene, is encoded using Motion-Compensated Prediction (MCP) among temporally successive frames. To provide efficient random access, we avoid MCP among temporally successive frames of the higher resolution layers. Instead, upward Prediction from the reconstructed thumbnail frames is used for coding high-resolution P slices. In this paper, we show that background extraction and long-term memory Motion-Compensated Prediction can reduce the bitrate by up to 85% while retaining efficient random access capability.

  • PCS - Background extraction and long-term memory Motion-Compensated Prediction for spatial-random-access-enabled video coding
    2009 Picture Coding Symposium, 2009
    Co-Authors: Aditya Mavlankar, Bernd Girod
    Abstract:

    Video streaming with virtual pan/tilt/zoom functionality allows the viewer to watch arbitrary regions of a high-spatial-resolution scene. A video coding scheme with random access to arbitrary regions of arbitrary zoom factors helps avoid transmission and/or decoding of the entire high-spatial-resolution video signal. The video coding scheme, proposed in our earlier work, creates a multi-resolution representation and uses P slices of H.264/AVC. The base layer, which provides a thumbnail overview of the entire scene, is encoded using Motion-Compensated Prediction (MCP) among temporally successive frames. To provide efficient random access, we avoid MCP among temporally successive frames of the higher resolution layers. Instead, upward Prediction from the reconstructed thumbnail frames is used for coding high-resolution P slices. In this paper, we show that background extraction and long-term memory Motion-Compensated Prediction can reduce the bitrate by up to 85% while retaining efficient random access capability.

  • Affine multipicture Motion-Compensated Prediction
    IEEE Transactions on Circuits and Systems for Video Technology, 2005
    Co-Authors: Thomas Wiegand, Eckehard Steinbach, Bernd Girod
    Abstract:

    Affine Motion compensation is combined with long-term memory Motion-Compensated Prediction. The idea is to determine several affine Motion parameter sets on subareas of the image. Then, for each affine Motion parameter set, a complete reference picture is warped and inserted into the multipicture buffer. Given the multipicture buffer of decoded pictures and affine warped versions thereof, block-based translational Motion-Compensated Prediction and Lagrangian coder control are utilized. The affine Motion parameters are transmitted as side information requiring additional bit rate. Hence, the utility of each reference picture and, with that, each affine Motion parameter set is tested for its rate-distortion efficiency. The combination of affine and long-term memory Motion-Compensated Prediction provides a highly efficient video compression scheme in terms of rate-distortion performance. The two incorporated multipicture concepts complement each other well providing almost additive rate-distortion gains. When warping the prior decoded picture, average bit-rate savings of 15% against TMN-10, the test model of ITU-T Recommendation H.263, are reported for the case that 20 warped reference pictures are used. When employing 20 warped reference pictures and 10 decoded reference pictures, average bit-rate savings of 24% can be obtained for a set of eight test sequences. These bit-rate savings correspond to gains in PSNR between 0.8-3 dB. For some cases, the combination of affine and long-term memory Motion-Compensated Prediction provides more than additive gains.

  • Multi-Frame Motion-Compensated Prediction for Video Transmission
    2001
    Co-Authors: Thomas Wiegand, Bernd Girod
    Abstract:

    Preface. Introduction. 1. State-Of-The-Art Video Transmission. 2. Rate-Constrained Coder Control. 3. Long-Term Memory Motion-Compensated Prediction. 4. Affine Multi-Frame Motion-Compensated Prediction. 5. Fast Motion Estimation for Multi-Frame Prediction. 6. Error Resilient Video Transmission. 7. Conclusions. References. Index.

  • multihypothesis Motion Compensated Prediction with forward adaptive hypothesis switching
    2001
    Co-Authors: Markus Flierl, Bernd Girod
    Abstract:

    Multihypothesis Motion-compensating predictors combine several Motion-Compensated signals to predict the current frame signal. More than one Motion-Compensated signal, or hypothesis, is selected for transmission. Long-term memory Motion-Compensated Prediction is a further concept for e‐cient video compression and is an example for forward-adaptive hypothesis switching. One Motion-Compensated signal is selected from multiple reference frames for transmission. This paper extends the theory of multihypothesis Motion-Compensated Prediction to forward-adaptive hypothesis switching. Assume, that we combine N hypotheses. Each hypothesis that is used for the combination is selected from a set of Motion-Compensated signals of size M. We study the in∞uence of the hypothesis set size M on both the accuracy of Motion compensation of forward-adaptive hypothesis switching and the e‐ciency of multihypothesis Motion-Compensated Prediction. In both cases, we examine the noise-free limiting case. That is, we neglect signal components that are not predictable by Motion compensation. Selecting one hypothesis from a set of Motion-Compensated signals of size M, that is, switching among M hypotheses, will reduce the displacement error variance by factor M when we assume statistically independent displacement errors. Integrating forward-adaptive hypothesis switching into multihypothesis Motion-Compensated Prediction, that is, allowing a combination of switched hypotheses, increases the gain of multihypothesis MotionCompensated Prediction over the single hypothesis case for growing hypothesis set size M.

C C J Kuo - One of the best experts on this subject based on the ideXlab platform.

  • Low-complexity H.264/AVC Motion Compensated Prediction for mobile video applications
    Applications of Digital Image Processing XXXIII, 2010
    Co-Authors: Szu-wei Lee, C C J Kuo
    Abstract:

    The performance of the Motion-Compensated Prediction (MCP) in video coding is degraded by aliasing due to spatial sampling. To alleviate this problem in H.264/AVC, a low-pass filter is used by the fractional-pel Motion estimation (FME) to suppress the aliasing component. However, the FME demands higher computational complexity on H.264/AVC encoding. In this work, we first perform a joint quantization and aliasing analysis on the H.264/AVC MCP process and show that the impact of the aliasing component can be alleviated by the quantization process. Then, we propose a fast Motion estimation (ME) algorithm that uses the FME and the integer-pel Motion estimation (IME) adaptively. The adaptive FME/IME algorithm examines the coding modes of the reference block for the current coding block, and then decides whether the FME or the IME should be applied to the current coding block. Experimental results show that the proposed adaptive FME/IME algorithm can help the encoder generate a bit stream at much lower computational complexity with small degradation in the coding gain as compared with a pure FME algorithm.

  • Analysis of multihypothesis Motion Compensated Prediction (MHMCP) for robust visual communication
    IEEE Transactions on Circuits and Systems for Video Technology, 2006
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    A multihypothesis Motion Compensated Prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra-refreshing scheme.

  • Design and analysis of multihypothesis Motion-Compensated Prediction (MHMCP) codec for error-resilient visual communications
    Multimedia Systems and Applications VII, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    A multi-hypothesis Motion Compensated Prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks in the frame buffer, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra refreshing scheme. Simulation results are given to confirm the analysis. Finally, several design principles for the MHMCP coder are derived based on the analytical and experimental results.

  • error resilience analysis of multihypothesis Motion Compensated Prediction for video coding
    International Conference on Image Processing, 2004
    Co-Authors: W Y Kung, Changsu Kim, C C J Kuo
    Abstract:

    The relationship between the error propagation effect and the hypothesis coefficients of the multihypothesis Motion Compensated Prediction (MHMCP) is analyzed in this work. MHMCP enhances the error resilience of compressed video but demands a higher bit rate for the Motion information. We study the rate-distortion performance of MHMCP in an error prone environment and then perform extensive experiments to conform the analytical results. Several design guidelines for MHMCP coders are drawn based on the analytical and experimental results.

  • analysis of multihypothesis Motion Compensated Prediction for error resilient video transmission
    Visual Communications and Image Processing, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    Multi-hypothesis Motion Compensated Prediction (MHMCP) predicts a block from a weighted sum of multiple reference blocks in the frame buffer. By efficiently combining these reference blocks, MHMCP can provide less Prediction errors so as to reduce the coding bit rates. Although MHMCP was originally proposed to achieve high coding efficiency, it has been observed recently that MHMCP can also enhance the error resilient property of compressed video. In this work, we investigate the error propagation effect in the MHMCP coder. More specifically, we study how the multi-hypothesis number as well as hypothesis coefficients influence the strength of propagating errors. Simulation results are given to confirm our analysis. Finally, several design principles for the MHMCP coder are derived based on our analysis and simulation results.

Weiying Kung - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of multihypothesis Motion Compensated Prediction (MHMCP) for robust visual communication
    IEEE Transactions on Circuits and Systems for Video Technology, 2006
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    A multihypothesis Motion Compensated Prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra-refreshing scheme.

  • Design and analysis of multihypothesis Motion-Compensated Prediction (MHMCP) codec for error-resilient visual communications
    Multimedia Systems and Applications VII, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    A multi-hypothesis Motion Compensated Prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks in the frame buffer, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra refreshing scheme. Simulation results are given to confirm the analysis. Finally, several design principles for the MHMCP coder are derived based on the analytical and experimental results.

  • analysis of multi hypothesis Motion Compensated Prediction for robust video transmission
    International Symposium on Circuits and Systems, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C Jay C Kuo
    Abstract:

    The relationship between the error propagation effect and the hypothesis number of a multi-hypothesis Motion Compensated Prediction (MHMCP) coder is analyzed in this work. MHMCP enhances the error resilient property of compressed video but demands a higher bit rate for the coding of Motion information. We study the rate-distortion performance of MHMCP in an error prone environment, and then perform extensive experiments to confirm analytical results. Several design guidelines for the MHMCP coder are drawn based on the analytical and experimental results.

  • analysis of multihypothesis Motion Compensated Prediction for error resilient video transmission
    Visual Communications and Image Processing, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    Multi-hypothesis Motion Compensated Prediction (MHMCP) predicts a block from a weighted sum of multiple reference blocks in the frame buffer. By efficiently combining these reference blocks, MHMCP can provide less Prediction errors so as to reduce the coding bit rates. Although MHMCP was originally proposed to achieve high coding efficiency, it has been observed recently that MHMCP can also enhance the error resilient property of compressed video. In this work, we investigate the error propagation effect in the MHMCP coder. More specifically, we study how the multi-hypothesis number as well as hypothesis coefficients influence the strength of propagating errors. Simulation results are given to confirm our analysis. Finally, several design principles for the MHMCP coder are derived based on our analysis and simulation results.

  • VCIP - Analysis of multihypothesis Motion-Compensated Prediction for error resilient video transmission
    Visual Communications and Image Processing 2004, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C.-c.j. Kuo
    Abstract:

    Multi-hypothesis Motion Compensated Prediction (MHMCP) predicts a block from a weighted sum of multiple reference blocks in the frame buffer. By efficiently combining these reference blocks, MHMCP can provide less Prediction errors so as to reduce the coding bit rates. Although MHMCP was originally proposed to achieve high coding efficiency, it has been observed recently that MHMCP can also enhance the error resilient property of compressed video. In this work, we investigate the error propagation effect in the MHMCP coder. More specifically, we study how the multi-hypothesis number as well as hypothesis coefficients influence the strength of propagating errors. Simulation results are given to confirm our analysis. Finally, several design principles for the MHMCP coder are derived based on our analysis and simulation results.

Changsu Kim - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of multihypothesis Motion Compensated Prediction (MHMCP) for robust visual communication
    IEEE Transactions on Circuits and Systems for Video Technology, 2006
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    A multihypothesis Motion Compensated Prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra-refreshing scheme.

  • Design and analysis of multihypothesis Motion-Compensated Prediction (MHMCP) codec for error-resilient visual communications
    Multimedia Systems and Applications VII, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    A multi-hypothesis Motion Compensated Prediction (MHMCP) scheme, which predicts a block from a weighted superposition of more than one reference blocks in the frame buffer, is proposed and analyzed for error resilient visual communication in this research. By combining these reference blocks effectively, MHMCP can enhance the error resilient capability of compressed video as well as achieve a coding gain. In particular, we investigate the error propagation effect in the MHMCP coder and analyze the rate-distortion performance in terms of the hypothesis number and hypothesis coefficients. It is shown that MHMCP suppresses the short-term effect of error propagation more effectively than the intra refreshing scheme. Simulation results are given to confirm the analysis. Finally, several design principles for the MHMCP coder are derived based on the analytical and experimental results.

  • error resilience analysis of multihypothesis Motion Compensated Prediction for video coding
    International Conference on Image Processing, 2004
    Co-Authors: W Y Kung, Changsu Kim, C C J Kuo
    Abstract:

    The relationship between the error propagation effect and the hypothesis coefficients of the multihypothesis Motion Compensated Prediction (MHMCP) is analyzed in this work. MHMCP enhances the error resilience of compressed video but demands a higher bit rate for the Motion information. We study the rate-distortion performance of MHMCP in an error prone environment and then perform extensive experiments to conform the analytical results. Several design guidelines for MHMCP coders are drawn based on the analytical and experimental results.

  • analysis of multi hypothesis Motion Compensated Prediction for robust video transmission
    International Symposium on Circuits and Systems, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C Jay C Kuo
    Abstract:

    The relationship between the error propagation effect and the hypothesis number of a multi-hypothesis Motion Compensated Prediction (MHMCP) coder is analyzed in this work. MHMCP enhances the error resilient property of compressed video but demands a higher bit rate for the coding of Motion information. We study the rate-distortion performance of MHMCP in an error prone environment, and then perform extensive experiments to confirm analytical results. Several design guidelines for the MHMCP coder are drawn based on the analytical and experimental results.

  • analysis of multihypothesis Motion Compensated Prediction for error resilient video transmission
    Visual Communications and Image Processing, 2004
    Co-Authors: Weiying Kung, Changsu Kim, C C J Kuo
    Abstract:

    Multi-hypothesis Motion Compensated Prediction (MHMCP) predicts a block from a weighted sum of multiple reference blocks in the frame buffer. By efficiently combining these reference blocks, MHMCP can provide less Prediction errors so as to reduce the coding bit rates. Although MHMCP was originally proposed to achieve high coding efficiency, it has been observed recently that MHMCP can also enhance the error resilient property of compressed video. In this work, we investigate the error propagation effect in the MHMCP coder. More specifically, we study how the multi-hypothesis number as well as hypothesis coefficients influence the strength of propagating errors. Simulation results are given to confirm our analysis. Finally, several design principles for the MHMCP coder are derived based on our analysis and simulation results.

Kenneth Rose - One of the best experts on this subject based on the ideXlab platform.

  • an adaptive linear estimator based approach to bi directional Motion Compensated Prediction
    International Conference on Acoustics Speech and Signal Processing, 2020
    Co-Authors: Jingning Han, Kenneth Rose
    Abstract:

    Bi-directional Motion Compensated Prediction is widely utilized in video coding. Conventionally, the encoder searches for two Motion vectors pointing to reference frames in both directions, and transmits these Motion vectors to the decoder. Recognizing that the two reference frames are already available to the decoder, prior work proposed decoder-side Motion estimation to extract Motion information or optical flow, at the cost of dramatic increase in decoder complexity. This paper proposes a novel bi-directional Motion compensation mode that efficiently utilizes the Motion information that is already available to the decoder, without recourse to extensive search. An estimation theory based approach is proposed and utilized to provide a high quality Prediction, which adaptively combines contributions from multiple Motion-Compensated references. Experimental results show that the proposed method, while yielding a greatly reduced decoder side complexity, introduces a significant coding gain for a diverse set of video sequences.

  • ICASSP - An Adaptive Linear Estimator Based Approach to Bi-Directional Motion Compensated Prediction
    ICASSP 2020 - 2020 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2020
    Co-Authors: Jingning Han, Kenneth Rose
    Abstract:

    Bi-directional Motion Compensated Prediction is widely utilized in video coding. Conventionally, the encoder searches for two Motion vectors pointing to reference frames in both directions, and transmits these Motion vectors to the decoder. Recognizing that the two reference frames are already available to the decoder, prior work proposed decoder-side Motion estimation to extract Motion information or optical flow, at the cost of dramatic increase in decoder complexity. This paper proposes a novel bi-directional Motion compensation mode that efficiently utilizes the Motion information that is already available to the decoder, without recourse to extensive search. An estimation theory based approach is proposed and utilized to provide a high quality Prediction, which adaptively combines contributions from multiple Motion-Compensated references. Experimental results show that the proposed method, while yielding a greatly reduced decoder side complexity, introduces a significant coding gain for a diverse set of video sequences.

  • adaptive interpolated Motion Compensated Prediction with variable block partitioning
    Data Compression Conference, 2018
    Co-Authors: Weiting Lin, Tejaswi Nanjundaswamy, Kenneth Rose
    Abstract:

    Conventional video coders rely heavily on pixel-domain block matching to remove temporal redundancies. This Prediction structure constrains pixels within a block to use the same Motion vector, which is ineffective for blocks with complex Motion. To mitigate this shortcoming we recently proposed a new paradigm of adaptive interpolated Motion compensation (AIMC), wherein neighboring Motion vectors are considered as pointers to multiple estimation sources, which are linearly combined to form the final Prediction, with weights chosen from pre-trained K-sets to capture variations in statistics. While promising initial results were obtained for fixed block sizes, this paper extends the approach to the important setting of variable block size partitioning, which has become standard in state-of-the-art video coding. Specifically, we propose a non-trivial generalization of AIMC to account for arbitrary block partitioning by “virtually” breaking a block to match its non-causal neighbors, and creating an interpolation tree structure, whose nodes extend from the original partitioning. This provides multiple estimates at the leaf nodes of the tree and enables an effective AIMC implementation. Experimental results validate the proposed paradigm with significant bit rate savings over conventional Motion Compensated Prediction.

  • DCC - Adaptive Interpolated Motion-Compensated Prediction with Variable Block Partitioning
    2018 Data Compression Conference, 2018
    Co-Authors: Tejaswi Nanjundaswamy, Kenneth Rose
    Abstract:

    Conventional video coders rely heavily on pixel-domain block matching to remove temporal redundancies. This Prediction structure constrains pixels within a block to use the same Motion vector, which is ineffective for blocks with complex Motion. To mitigate this shortcoming we recently proposed a new paradigm of adaptive interpolated Motion compensation (AIMC), wherein neighboring Motion vectors are considered as pointers to multiple estimation sources, which are linearly combined to form the final Prediction, with weights chosen from pre-trained K-sets to capture variations in statistics. While promising initial results were obtained for fixed block sizes, this paper extends the approach to the important setting of variable block size partitioning, which has become standard in state-of-the-art video coding. Specifically, we propose a non-trivial generalization of AIMC to account for arbitrary block partitioning by “virtually” breaking a block to match its non-causal neighbors, and creating an interpolation tree structure, whose nodes extend from the original partitioning. This provides multiple estimates at the leaf nodes of the tree and enables an effective AIMC implementation. Experimental results validate the proposed paradigm with significant bit rate savings over conventional Motion Compensated Prediction.

  • DCC - Adaptive Interpolated Motion-Compensated Prediction with Variable Block Partitioning
    2018 Data Compression Conference, 2018
    Co-Authors: Weiting Lin, Tejaswi Nanjundaswamy, Kenneth Rose
    Abstract:

    Conventional video coders rely heavily on pixel-domain block matching to remove temporal redundancies. This Prediction structure constrains pixels within a block to use the same Motion vector, which is ineffective for blocks with complex Motion. To mitigate this shortcoming we recently proposed a new paradigm of adaptive interpolated Motion compensation (AIMC), wherein neighboring Motion vectors are considered as pointers to multiple estimation sources, which are linearly combined to form the final Prediction, with weights chosen from pre-trained K-sets to capture variations in statistics. While promising initial results were obtained for fixed block sizes, this paper extends the approach to the important setting of variable block size partitioning, which has become standard in state-of-the-art video coding. Specifically, we propose a non-trivial generalization of AIMC to account for arbitrary block partitioning by “virtually” breaking a block to match its non-causal neighbors, and creating an interpolation tree structure, whose nodes extend from the original partitioning. This provides multiple estimates at the leaf nodes of the tree and enables an effective AIMC implementation. Experimental results validate the proposed paradigm with significant bit rate savings over conventional Motion Compensated Prediction.