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error-resilient video coding using long-term memory prediction and feedback channel

SIGNAL PROCESSING-IMAGE COMMUNICATION 2002年第8期17卷 597-609页

作者： Jung, HS Kim, RC Lee, SU Seoul Natl Univ Sch Elect Engn & Comp Sci Inst New Media & Comm Gwanak Gu Seoul 151742 South Korea Seoul Natl Univ Dept Elect & Comp Engn Seoul South Korea

The MC-DCT-based video coding has been generally used for its efficiency and easy implementation, but it is very vulnerable in error-prone environments. In this paper, we address an error-resilient video coding using multiple reference frame, based on the long-term memory motion compensated prediction (LTMP) (IEEE Trans. Circuits Syst. video Technol. 9 (1) (1999) 70), and an error concealment technique associated with the proposed technique. The rate-distortion optimization of T. Wiegand et al. (1999) is modified by adding dispersion measure of the temporal motion vectors in order to provide the error-resiliency and much improved error concealment performance. Also, the proposed algorithm confines the temporal error propagation using negative acknowledgement in feedback channel, in which both the corrupted area by channel errors and the error-propagated area are estimated and removed from the search region for the motion compensation. Thus, the proposed algorithm yields the similar performance to the forced intra update (FIU) in terms of the PSNR, but avoids the abrupt increase in the bitrate, resulting in more efficient network utilization than the FIU. By the computer simulations, we shall demonstrate that the proposed technique provides an acceptable performance both subjectively and objectively in error-prone environments, as compared with H.263 and LTMP, with or without the feedback messages. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： error-resilient video coding multiple reference frame long-term memory prediction error concealment feedback channel dispersion measure of the temporal motion vectors

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error-resilient image and video coding for wireless communication systems

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ELECTRONICS & COMMUNICATION ENGINEERING JOURNAL 1998年第4期10卷 181-190页

作者： Redmill, DW Bull, DR Chung-How, JT Kingsbury, NG Univ Bristol Dept Elect & Elect Engn Ctr Commun Res Bristol BS8 1UB Avon England Univ Cambridge Dept Engn Cambridge CB2 1PZ England

Current techniques for coding images and video sources with resilience to channel errors can remove much of the need for complex high-redundancy channel coding and provide a graceful degradation of performance with decreasing channel quality. The main function of these error-resilient techniques is to reduce the propagation of errors within the decoded data. Two main techniques are discussed in detail in this paper: the error-resilient entropy code (EREC) and pyramid vector quantisation (PVQ). The paper concludes with a brief comparison of the relative merits of these systems and areas for further consideration.

关键词： error-resilient video coding ARQ protocol channel coding Pattern recognition PVQ error propagation performance error-resilient image coding Codes channel errors channel quality EREC entropy codes video sources error-resilient entropy code image coding Optical information, image and video signal processing pyramid vector quantisation decoded data Computer vision and image processing techniques radiocommunication wireless communication systems vector quantisation coding errors video coding

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An enhanced two-stage multiple description video coder with drift reduction

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2004年第1期14卷 122-127页

作者： Lee, YC Altunbasak, Y Mersereau, RM Georgia Inst Technol Sch Elect & Comp Engn Ctr Signal & Image Proc Atlanta GA 30332 USA

Multiple description coding (MDC) is a source coding technique that exploits path diversity to increase the robustness of transmitting a compressed signal over error-prone channels. However, the application of MDC to video coding is still problematic because a prediction mismatch problem, called drift, may occur at the decoder when one description is lost. In the literature, it has been shown that drift can be effectively prevented by encoding this prediction mismatch and sending it as side information in a three-prediction-loop structure. However, this side information is totally redundant when both descriptions are received. In this paper, we propose a very simple, but efficient two-stage MDC in the central prediction loop based on Reibman's three-prediction-loop structure. In our design, an additional multiple description scalar quantizer is introduced into the central prediction loop. The encoding of the side information is modified in such a way that it can be used to improve the video quality when no drift occurs, but All maintain drift prevention capability. The simulation results with different video sequences at various packet loss rates demonstrate that the proposed two-stage MDC structure indeed enhances the quality when the channel is error-free, yet effectively avoids drift when one description is completely lost.

关键词： drift problem error-resilient video coding motion-compensated multiple description prediction multiple description coding (MDC) multiple description scalar quantization (MDSQ) video streaming

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An efficient motion compensation algorithm based on double reference frame method

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2002年第8期17卷 635-649页

作者： Kim, SH Kim, CS Lee, SU Seoul Natl Univ Inst New Media & Commun Sch Elect Engn & Comp Sci Seoul 151742 South Korea

Recently, several techniques based on the multiple reference frame scheme (Proceedings of the Dada Compression Conference, March 1998, pp. 239-248;Proceedings of the European Signal Processing Conference, September 1998, pp. 253-256;Proceedings of the International Symposium on Information Theory, August 1998, pp. 409-418;IEEE Trans. Circuits Systems video Technol. 9(1) (February 1999) 70-84;Proceedings of the IEEE International Conference on Image Processing, October 1997, pp. 17-20) have been proposed to improve the motion prediction gain. Though these techniques yield higher prediction gain than the single reference frame scheme, they cannot maintain acceptable image quality at very low bitrate. Besides, the blocking artifacts may be visible along the block boundaries, since each block is predicted independently of its neighbors. And they require tremendous computational complexity for the motion search. To overcome these drawbacks, this paper proposes a novel motion compensation algorithm, based on the double reference frame, the double motion vector, and the searching position shifting (SPS) schemes. First, to reduce the motion vector bitrate and the computational complexity of motion search, we constrain the number of reference frames to 2, and use only two motion vectors per block. Second, to alleviate the blocking artifacts and to yield better prediction performance, the SPS scheme is introduced. Experimental results demonstrate that the proposed algorithm yields about 3-4 dB higher prediction gain than the single reference frame scheme. Subjective quality is also improved by alleviating the blocking artifacts. In addition, the proposed algorithm can be combined with a robust video transmission scheme. Thus, even if the channel experiences errors during the transmission, the proposed algorithm can efficiently protect the image quality. (C) 2002 Published by Elsevier Science B.V.

关键词： motion compensation very low bitrate video coding multiple reference frame multiple motion vector searching position shifting scheme error-resilient video coding

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Advances in channel-adaptive video streaming

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WIRELESS COMMUNICATIONS & MOBILE COMPUTING 2002年第6期2卷 573-584页

作者： Girod, B Kalman, M Liang, YJ Zhang, R Stanford Univ Dept Elect Engn Informat Syst Lab Stanford CA 94305 USA

Despite the well-known challenges of variations in throughput, delay, and packet loss over the Internet, video streaming has experienced phenomenal growth, owing to the extensive research in video coding and transmission. In this paper, we review several recent advances for channel-adaptive video streaming that, we believe, will benefit the design of video streaming systems in the future. Employed in different components of the system, these techniques have the common objective of providing efficient, robust, scalable, and low-latency streaming video. Firstly, by allowing the client to control the rate at which it consumes data, adaptive media playout can be used to reduce receiver buffering and therefore average latency, and provide limited rate scalability. Secondly, rate-distortion optimized packet scheduling, a transport technique, provides a flexible framework to determine the best packet to send, given the channel behaviors, the packets' deadlines, their transmission histories, the distortion reduction associated with sending each packet, and the interpacket dependencies. Thirdly, at the source encoder, channel-adaptive packet-dependency control can greatly improve the error resilience of streaming video and reduce latency. Finally, we address the specific additional challenges for wireless video streaming. We consider three architectures for wireless video and discuss the utility of the reviewed techniques for each architecture. Copyright (C) 2002 John Wiley Sons, Ltd.

关键词： multimedia communication video streaming wireless video error-resilient video coding low latency rate distortion scalability source-channel coding

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Performance of Spatial and Temporal error Concealment Method for 3D DWT video coding in Packet Loss Channel

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2012年第11期E95A卷 2015-2022页

作者： Tanaka, Hirokazu Kim, Sunmi Ogawa, Takahiro Haseyama, Miki Toshiba Co Ltd Minato Ku Tokyo 1058001 Japan Hokkaido Univ Grad Sch Informat Sci & Technol Sapporo Hokkaido 0600814 Japan

A new spatial and temporal error concealment method for three-dimensional discrete wavelet transform (3D DWT) video coding is analyzed. 3D DWT video coding employing dispersive grouping (DG) and two-step error concealment is an efficient method in a packet loss channel [20], [21]. In the two-step error concealment method, the interpolations are only spatially applied however, higher efficiency of the interpolation can be expected by utilizing spatial and temporal similarities. In this paper, we propose an enhanced spatial and temporal error concealment method in order to achieve higher error concealment (EC) performance in packet loss networks. In the temporal error concealment method, structural similarity (SSIM) index is employed for inter group of pictures (GOP) EC and minimum mean square error (MMSE) is used for intra GOP EC. Experimental results show that the proposed method can obtain remarkable performance compared with the conventional methods.

关键词： 3D wavelet video coding error-resilient video coding structural similarity index error concealment

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error-resilient H.264/AVC video Transmission Using Two-Way Decodable Variable Length Data Block

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2010年第3期20卷 340-350页

作者： Gao, Shaoshuai Ma, Kai-Kuang Chinese Acad Sci Grad Univ Sch Informat Sci & Engn Beijing 100049 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

Standard video coders utilize variable length coding (VLC) to obtain more data compression in addition to what lossy coding has achieved at the expense of making the compressed bitstream very vulnerable to channel errors. Even a 1-bit error incurred in the bitstream may cause the follow-up bitstream to be either erroneously decoded or completely undecodable, and this could further result in error propagation. To mitigate this phenomenon, a new VLC coding scheme is proposed in this paper, called the two-way decodable variable length data block (TDVLDB), which allows the compressed bitstream to be bidirectionally decodable without exploiting data partitioning. The proposed TDVLDB scheme is able to effectively recover more uncorrupted data from the corrupted packets. Furthermore, it is able to correct some, if not all, channel errors of a finite-length burst error. To effectively identify the location of the first actual error incurred within the current slice, a bitstream similarity measurement (BSM) algorithm is proposed. Note that the proposed TDVLDB scheme is generic in the sense that it can be exploited in any image or video coding framework as long as it involves the use of VLC and requires error-resilience capability. In this paper, the proposed TDVLDB is incorporated into the H.264/advanced video coding (AVC) coder to evaluate its error-resilience performance in terms of rate-distortion coding efficiency. Compared with the baseline H.264/AVC coding, the TDVLDB-incorporated H.264/AVC-based coding scheme has demonstrated significant objective and subjective video quality improvements when the bitstream is transmitted over error-prone channels.

关键词： Bidirectional decoding error concealment error-resilient video coding H.264/AVC resynchronization reversible variable length coding two-way decoding wireless video transmission

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H.264/AVC in wireless environments

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2003年第7期13卷 657-673页

作者： Stockhammer, T Hannuksela, MM Wiegand, T Tech Univ Munich Inst Commun Engn D-80290 Munich Germany Heinrich Hertz Inst Nachrichtentech Berlin GmbH Fraunhofer Inst Telecommun D-10587 Berlin Germany Nokia Electr Ltd Tampere 33721 Finland

video transmission in wireless environments is a challenging task calling for high-compression efficiency as well as a network friendly design. Both have been major goals of the H.264/AVC standardization effort addressing "conversational" (i.e., video telephony) and "nonconversational" (i.e., storage, broadcast, or streaming) applications. The video compression performance of the H.264/AVC video coding layer typically provides a significant improvement. The network-friendly design goal of H.264/AVC is addressed via the network abstraction layer that has been developed to transport the coded video data over any existing and future networks including wireless systems. The main objective of this paper is to provide an overview over the tools which are likely to be used in wireless environments and discusses the most challenging application, wireless conversational services in greater detail. Appropriate justifications for the application of different tools based on experimental results are presented.

关键词： error concealment error-resilient video coding H.264/AVC multiple reference frames rate-distortion optimization video coding standards wireless video transmission

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Enhanced MIMO wireless video communication using multiple-description coding

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2008年第4期23卷 325-336页

作者： Tesanovic, Milos Bull, David Doufexi, Angela Nix, Andrew Univ Bristol Ctr Commun Res Bristol Avon England

Significant enhancements in spectral efficiency and error-resilience must be obtained from emerging wireless video systems if high-quality multimedia transmission is to become cost-effective. MIMO (multiple-input-multiple-output) technology promises to deliver the sustainable high transmission quality required for such applications. MIMO is a generic technology which, depending on the actual architecture deployed and the channel conditions encountered, produces variable error conditions. In particular, the way these errors interact with the transmitted data will depend on both the data source and the coding mechanism employed. In this context, this paper focuses on the interactions when MIMO systems are used to transmit compressed video. In terms of multimedia transmission, spatial multiplexing (SM) has often been proposed as the most suitable MIMO technique. Most SM-based video transport schemes focus on the advantages of multiplexing gain, which are achieved at the expense of relatively high SNR values. This paper proposes the use of multiple-description video coding (MDC) as a means of emulating the spatial diversity lacking in SM systems, to provide a new class of wireless video transmission algorithm. Singular value decomposition (SVD) is employed to create orthogonal sub-channels which provide an efficient means of mapping video content to the wireless channels. Extensive simulations demonstrate the effectiveness of MDC as a video decomposition which couples well with the underpinning SVD architecture. In addition, resource allocation in MIMO-SVD systems is examined in the context of transmitted video quality, and further enhancements have been achieved for low SNR values. Results indicate improvements in average PSNR of the decoded test sequences of around 5-7 dB, compared to standard, single-description video transmission. This is further enhanced by an additional 2-3 dB in the case of channels with low SNR values through the use of unequal power allocation.

关键词： multimedia communication MIMO systems video processing error-resilient video coding multiple-description coding (MDC) video mapping

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A Robust error Detection Mechanism for H.264/AVC Coded video Sequences Based on Support Vector Machines

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2008年第12期18卷 1766-1770页

作者： Farrugia, Reuben A. Debono, Carl James Univ Malta Dept Commun & Comp Engn Msida 2080 MSD Malta

Current trends in wireless communications provide fast and location-independent access to multimedia services. Due to its high compression efficiency, H.264/AVC is expected to become the dominant underlying technology in the delivery of future wireless video applications. The error resilient mechanisms adopted by this standard alleviate the problem of spatio-temporal propagation of visual artifacts caused by transmission errors by dropping and concealing all macroblocks (MBs) contained within corrupted segments, including uncorrupted MBs. Concealing these uncorrupted MBs generally causes a reduction in quality of the reconstructed video sequence. This paper presents a novel error detection algorithm which employs the checksum of the transport layer protocol to detect corrupted segments. Each MB within the corrupted segment is passed through a support vector machine (SVM) classifier to detect and localize visually distorted MBs. The proposed solution was tested on a wide range of video sequences, where on average 95.25% of the residual corrupted MBs which provide annoying visual artifacts were detected. This method reduces the number of uncorrupted MBs to be concealed resulting in a significant gain in quality compared to the standard H.264/AVC decoder.

关键词： error-resilient video coding H.264/AVC learning systems video coding wireless video transmission

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