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A Practical Code Rate Decision Scheme Based on Playable Bitrate Model for error-resilient Joint Source-Channel coding

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IEICE TRANSACTIONS ON COMMUNICATIONS 2011年第3期E94B卷 676-685页

作者： Jeong, Yo-Won Seo, Kwang-Deok Park, Kyu Ho Korea Adv Inst Sci & Technol Dept Elect Engn Taejon 305701 South Korea Yonsei Univ Comp & Telecommun Engn Div Wonju 220710 Gangwon South Korea

Joint source-channel coding (JSCC) is a method to jointly allocate the given total transmission bitrate to the source coding and channel coding to maximize the video quality at the receiving end. In this paper, we propose a practical model for efficiently determining a near-optimal code rate for JSCC in real-time video communications. The conventional code rate decision schemes using analytical source coding distortion model and channel-induced distortion model are usually complex, and typically employ the process of model parameter training which involves potentially high computational complexity and implementation cost. To avoid the complex modeling procedure, we introduce a very simple video quality model based on the playable bitrate which is defined as the total bit amount per unit time that is not affected by the channel loss during transmission including correctly recovered bits by the channel decoder. Because the video quality at the receiving end is clearly commensurate with the playable bitrate, we can easily determine the quality-oriented near-optimal code rate by finding the code rate that maximizes the playable bitrate at the sender side. The proposed playable bitrate model is very simple because it does not require the complex training procedure for obtaining model parameters, which is usually required in the conventional code rate decision method. It is shown by simulations that the proposed code rate decision scheme based on the playable bitrate model can efficiently determine the near-optimal code rate for JSCC in terms of high accuracy on the optimal code rate.

关键词： joint source-channel coding code rate decision error-resilient video coding forward error correction

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Rate distortion optimized coding mode selection for H.264/AVC in wireless environments

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IEICE TRANSACTIONS ON COMMUNICATIONS 2004年第7期E87B卷 2057-2060页

作者： Zhang, W Zhou, YH Shanghai Jiao Tong Univ Inst Image Commun & Informat Proc Shanghai 200030 Peoples R China

A flexible and robust rate-distortion optimization algorithm is presented to select macroblock coding mode for H.264/AVC transmission over wireless channels subject to burst errors. A two-state Markov model is used to describe the burst errors on the packet level. With the feedback information from the receiver and the estimation of the channel errors, the algorithm analyzes the distortion of the reconstructed macroblock at the decoder due to the channel errors and spatial and temporal error propagation. The optimal coding mode is chosen for each macroblock in rate-distortion (R-D)-based framework. Experimental results using the H.264/AVC test model show a significant performance of resilience to the burst errors.

关键词： coding mode error-resilient video coding H.264/AVC rate-distortion optimization wireless video transmission

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Towards robust AV conferencing on next-generation networks

Towards robust AV conferencing on next-generation networks

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Conference on Multimedia Computing and Networking 2005

作者： Liu, HN Cheng, L El Zarki, M Univ Calif Irvine Sch Informat & Comp Sci Irvine CA 92697 USA

ISBN: (纸本)0819456535

In order to enable a truly pervasive computing environment, next generation networks (including B3G and 4G) will merge the broadband wireless and wireline networking infrastructure. However, due to the tremendous complexity in administration and the unreliability of the wireless channel, provision of hard-guarantees for services on such networks will not happen in the foreseeable future. This consequently makes it particularly challenging to offer viable AV conferencing services due to their stringent synchronization, delay and data fidelity requirements. We propose in this paper a robust application-level solution for wireless mobile AV conferencing on B3G/4G networks. Expecting no special treatment from the network, we apply a novel adaptive delay and synchronization control mechanism to maintain the synchronization and reduce the latency as much as possible. We also employ a robust video coding technique that has better error-resilience capability. We investigate the performance of the proposed solution through simulations using a three-state hidden Markov chain as the generic end-to-end transport channel model. The results show that our scheme yields tight synchronization performance, relatively low end-to-end latency and satisfactory presentation quality. The scheme successfully provides a fairly robust AV conferencing service.

关键词： B3G/4G networks AV conferencing adaptive delay and synchronization control error-resilient video coding

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Reliable video communication over lossy packet networks using multiple state encoding and path diversity

Reliable video communication over lossy packet networks usin...

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Conference on Visual Communications and Image Processing 2001

作者： Apostolopoulos, JG Hewlett Packard Labs Palo Alto CA 94304 USA

ISBN: (纸本)0819439886

video communication over lossy packet networks such as the Internet is hampered by limited bandwidth and packet loss. This paper presents a system for providing reliable video communication over these networks, where the system is composed of two subsystems: (1) multiple state video encoder/decoder and (2) a path diversity transmission system. Multiple state video coding combats the problem of error propagation at the decoder by coding the video into multiple independently decodable streams, each with its own prediction process and state. If one stream is lost the other streams can still be decoded to produce usable video, and furthermore, the correctly received streams provide bidirectional (previous and future) information that enables improved state recovery for the corrupted stream. This video coder is a form of multiple description coding (MDC), and its novelty lies in its use of information from the multiple streams to perform state recovery at the decoder. The path diversity transmission. system explicitly sends different subsets of packets over different paths, as opposed to the default scenarios where the packets proceed along a single path, thereby enabling the end-to-end video application to effectively see an average path behavior. We refer to this as path diversity. Generally, seeing this average path behavior provides better performance than seeing the behavior of any individual random path. For example, the probability that all of the multiple paths are simultaneously congested is much less than the probability that a single path is congested. The resulting path diversity provides the multiple state video decoder with an appropriate virtual channel to assist in recovering from lost packets, and can also simplify system design, e.g. FEC design. We propose two architectures for achieving path diversity, and examine the effectiveness of path diversity in communicating video over a lossy packet network.

关键词： error-resilient video coding video streaming multiple description coding path diversity packet video wireless video

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Robust low-delay video transmission using H.264/AVC redundant slices and flexible macroblock ordering

Robust low-delay video transmission using H.264/AVC redundan...

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IEEE International Conference on Image Processing (ICIP 2007)

作者： Baccichet, Pierpaolo Rane, Shantanu Chimienti, Antonio Girod, Bernd Max Planck Ctr Visual Comp & Commun Stanford CA 94305 USA Stanford Univ Informat Syst Lab Stanford CA 94305 USA IEIIT Natl Res Council Turin Italy

ISBN: (纸本)9781424414369

This paper proposes a scheme for low-delay robust transmission of video signals over packet erasure channels. In applications such as video conferencing, the permissible delay between encoding and playback may be too low to allow retransmission or channel coding approaches which require buffering several video packets. For such a scenario, we present a scheme that provides error robustness using redundant video descriptions applied to pertinent portions of the video signal. In the H.264/AVC specification, this can be efficiently implemented using redundant slices and Flexible Macroblock Ordering (FMO). We describe a model that determines the bit rate of the redundant descriptions such that the expected distortion at the decoder is minimized. Across all the video test sequences used, the average video quality delivered by the proposed scheme is 3.7 dB higher than decoder-based error concealment, and 1.2 dB higher than encoder-based loss-aware rate-distortion optimization.

关键词： error-resilient video coding H.264/AVC flexible macroblock ordering redundant slices

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Performance Improvement of error-resilient 3D DWT video Transmission Using Invertible Codes

Performance Improvement of Error-Resilient 3D DWT Video Tran...

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38th Symposium on Information Theory and its Applications (SITA)

作者： Omura, Kotoku Yamasaki, Shoichiro Matsushima, Tomoko K. Tanaka, Hirokazu Haseyama, Miki Polytech Univ Kodaira Tokyo 1870035 Japan Hiroshima City Univ Grad Sch Informat Sci Hiroshima 7313194 Japan Hokkaido Univ Grad Sch Informat Sci & Technol Sapporo Hokkaido 0600814 Japan

Many studies have applied the three-dimensional discrete wavelet transform (3D DWT) to video coding. It is known that corruptions of the lowest frequency sub-band (LL) coefficients of 3D DWT severely affect the visual quality of video. Recently, we proposed an error resilient 3D DWT video coding method (the conventional method) that employs dispersive grouping and an error concealment (EC). The EC scheme of our conventional method adopts a replacement technique of the lost LL coefficients. In this paper, we propose a new 3D DWT video transmission method in order to enhance error resilience. The proposed method adopts an error correction scheme using invertible codes to protect LL coefficients. We use half-rate Reed-Solomon (RS) codes as invertible codes. Additionally, to improve performance by using the effect of interleave, we adopt a new configuration scheme at the RS encoding stage. The evaluation by computer simulation compares the performance of the proposed method with that of other EC methods, and indicates the advantage of the proposed method.

关键词： 3D DWT video coding error-resilient video coding error concealment Reed-Solomon codes

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H.264-based multiple description video coder and its DSP implementation

H.264-based multiple description video coder and its DSP imp...

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IEEE International Conference on Image Processing (ICIP 2006)

作者： Wei, Zhe Cai, Canhui Ma, Kai-Kuang Huaqiao Univ Inst Informat Sci & Engn Quanzhou 362021 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

ISBN: (纸本)9781424404810

In this paper, a novel H.264-based multiple description coding (MDC) framework, called the prediction-based spatial polyphase transform (PSPT) multiple description video coding, is introduced to enhance the error-resilience ability and reduce the computational complexity of the H.264 codec. The proposed PSPT-MDC down-samples each input frame in both the horizontal and the vertical directions, forming four subframes. Instead of directly coding and transporting all the four subframes, two of them are predicted from the other two subframes. The proposed H.264-based PSPT-MDC video codec is then implemented on the TI TMS320C6416 digital signal processor with some optimizations to demonstrate its feasibility and attractive performance, in terms of the decoded video quality and error-resilience capability.

关键词： h.264 multiple description coding error-resilient video coding digital signal processor codec cache memory

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Systematic lossy error protection of video based on H.264/AVC redundant slices

Systematic lossy error protection of video based on H.264/AV...

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Conferenceon Visual Communications and Image Processing 2006

作者： Rane, S Girod, B Stanford Univ Informat Syst Lab Stanford CA 94305 USA

ISBN: (纸本)0819461172

We propose the use of H.264 redundant slices for Systematic Lossy error Protection (SLEP) of a video signal transmitted over an error-prone channel. In SLEP, the video signal is transmitted to the decoder without channel coding. Additionally, a Wyner-Ziv encoded version of the video signal is transmitted in order to provide error-resilience. In the event of channel errors, the Wyner-Ziv description is decoded as a substitute for the error-prone portions of the primary video signal. Since the Wyner-Ziv description is typically coarser than the primary video signal, SLEP is a lossy error protection technique which trades-off residual quantization distortion for improved error-resilience properties, such as graceful degradation of decoder picture quality. We describe how H.264 redundant slices can be used to generate the Wyner-Ziv description, and present simulation results to demonstrate the advantages of this method over traditional methods such as FEC.

关键词： systematic lossy source-channel coding systematic lossy error protection Wyner-Ziv coding Slepian-Wolf coding side information redundant slices error-resilient video coding distributed video coding

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Network-adaptive video communication using packet path diversity and rate-distortion optimized reference picture selection

Network-adaptive video communication using packet path diver...

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5th IEEE Workshop on Multimedia Signal Processing (MMSP 2002)

作者： Liang, YJ Setton, E Girod, B Stanford Univ Dept Elect Engn Informat Syst Lab Stanford CA 94305 USA

In this paper, we present error-resilient Internet video transmission using path diversity and rate-distortion optimized reference picture selection. Under this scheme, the optimal packet dependency is determined adapting to network characteristics and video content, to achieve a better trade-off between coding efficiency and forming independent streams to increase error-resilience. The optimization is achieved within a rate-distortion framework, so that the expected end-to-end distortion is minimized under the given rate constraint. The expected distortion is calculated based on an accurate binary tree modeling with the effects of channel loss and error concealment taken into account. With the aid of active probing, packets are sent across multiple available paths according to a transmission policy which takes advantage of path diversity and seeks to minimize the loss rate. Experiments demonstrate that the proposed scheme provides significant diversity gain, as well as gains over video redundancy coding and the NACK mode of conventional reference picture selection.

关键词： Path diversity network-adaptive video coding error-resilient video coding source-channel coding reference picture selection low-latency rate-distortion optimization video streaming

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ISMA MPEG-4 video quality analysis

ISMA MPEG-4 video quality analysis

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Conference on Ultrahigh- and High-Speed Photography, Photonics and videography

作者： Han, KJ Suter, BW Air Force Res Lab Informat Directorate Ctr Integrated Transmiss & Exploitat Rome NY 13441 USA

ISBN: (纸本)0819450839

Transporting MPEG-4 video over the Internet is expected to be an important component of many multimedia applications. The ISMA (Internet Streaming Media Alliance) has defined two hierarchical profiles to stream video content on wireless and narrow band networks, and over broadband quality networks. The evaluation mechanisms to assess the quality of video will play a major role in the overall design of video communication. However, the ISMA (Internet Streaming Media Alliance) MPEG-4 video quality analysis has not been reported. This paper presents statistical video quality analysis for the ISMA MPEG-4 video clips. Shannon entropies and principle components are used to interpret the degraded video quality in video sequences. Moreover, the current trends in error resilient video coding techniques and the error control/resilience solutions will be discussed.

关键词： video quality metric (VQM) video communication error-resilient video coding MPEG-2 MPEG-4 3-D SPIHT Shannon Entropy synchronization variable length codes fixed-length codes high compression joint source and channel coding burst errors forward error correction (FEC) principal component analysis Eigen

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