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Multilayered protection of embedded video bitstreams over binary symmetric and packet erasure channels

JOURNAL OF VISUAL COMMUNICATION AND IMAGE REPRESENTATION 2005年第3期16卷 359-378页

作者： Cho, SD Pearlman, WA Rensselaer Polytech Inst Ctr Image Proc Res Dept Elect Comp & Syst Engn Troy NY 12180 USA

This paper presents a multilayered protection of embedded video bitstreams over bit errors and packet erasure channels using Error Resilient and Error Concealment 3-D SPIHT (ERC-SPIHT) algorithm, which is based on the 3-D SPIHT concepts. A robust source coder is created to give error resilience in source level of the codestream. This robustness is achieved by partitioning the wavelet coefficients into many independent sub-bitstreams while maintaining spatio-temporal tree structures. For higher protection against channel noise, we use a product code. In each packet, the concatenation of a rate compatible punctured convolutional (RCPC) code and an error detecting parity check (CRC) code is used. Across the packets, Reed-Solomon codes are used. These steps provide the robust source coder with additional layers of protection against channel noise. Finally, in the decoder side, an error concealment function is performed for the lost blocks. Simulations show that the multilayered protection of 3-D SPIHT outperforms the methods that use single layer protection in terms of average PSNRs and the PSNR ranges, and provides higher average PSNR's and lower PSNR variances. (C) 2004 Elsevier Inc. All rights reserved.

关键词： video compression video transmission robust source coding error resilient transmission joint source and channel coding 3-D wavelet transform embedded wavelet coding

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An unequal error protection method for progressively transmitted 3-D models

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IEEE TRANSACTIONS ON MULTIMEDIA 2005年第4期7卷 766-776页

作者： AlRegib, G Altunbasak, Y Rossignac, J Georgia Tech Ctr Signal & Image Proc Atlanta GA 30332 USA Georgia Inst Technol Sch Elect & Comp Engn Savannah GA 31407 USA Georgia Inst Technol Coll Comp Atlanta GA 30332 USA Georgia Inst Technol GVU Ctr Atlanta GA 30332 USA

In this paper, we present a packet-loss resilient system for the transmission of progressively compressed three-dimensional (3-D) models. It is based on a joint source and channel coding approach that trades off geometry precision for increased error resiliency to optimize the decoded model quality on the client side. We derive a theoretical framework for the overall system by which the channel packet loss behavior and the channel bandwidth can be directly related to the decoded model quality at the receiver. First, the 3-D model is progressively compressed into a base mesh and a number of refinement layers. Then, we assign optimal forward error correction code rates to protect these layers according to their importance to the decoded model quality. Experimental results show that with the proposed unequal error protection approach, the decoded model quality degrades more gracefully (compared to either no error protection or equal error protection methods) as the packet-loss rate increases.

关键词： joint source and channel coding multimedia networking packet loss resilient transmission unequal error protection (UEP) virtual reality over IP networks 3-D graphics streaming

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An integrated source and channel rate allocation scheme for robust video coding and transmission over wireless channels

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EURASIP JOURNAL ON APPLIED SIGNAL PROCESSING 2004年第2期2004卷 304-316页

作者： Song, J Liu, KJR Media Connect Div Agere Syst Holmdel NJ 07733 USA Univ Maryland Dept Elect & Comp Engn College Pk MD 20742 USA

A new integrated framework for source and channel rate allocation is presented for video coding and transmission over wireless channels without feedback channels available. For a fixed total channel bit rate and a finite number of channel coding rates, the proposed scheme can obtain the near-optimal source and channel coding pair and corresponding robust video coding scheme such that the expected end-to-end distortion of video signals can be minimized. With the assumption that the encoder has the stochastic information such as average SNR and Doppler frequency of the wireless channel, the proposed scheme takes into account robust video coding, channel coding, packetization, and error concealment techniques altogether. An improved method is proposed to recursively estimate the end-to-end distortion of video coding for transmission over error-prone channels. The proposed estimation is about 1-3 dB more accurate compared to the existing integer-pel-based method. Rate-distortion-optimized video coding is employed for the trade-off between coding efficiency and robustness to transmission errors.

关键词： multimedia communications joint source and channel coding wireless video

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Information and signal processing for sensor networks

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2004年第10期E87A卷 2599-2606页

作者： Ogawa, A Yamazato, T Ohtsuki, T Meijo Univ Dept Informat Engn Nagoya Aichi 4688502 Japan Nagoya Univ Ctr Informat Media Studies Nagoya Aichi 4648603 Japan Tokyo Univ Sci Dept Elect Engn Noda Chiba 2788510 Japan

Sensor networks, in which a large number of sensor nodes are connected with each other through communication networks, are potential to provide extensive new applications with various research and technical challenges and attracting much attention all over the world. In this paper we describe information and signal processing for sensor networks with emphasis on the concepts of collaboration and fusion as one of the most important issues for the sensor networks. We also review some basic aspects of sensor networks in terms of their features and the network architecture.

关键词： sensor networks collaborative infonnation and signal processing joint source and channel coding deterministic and statistic collaboration cooperative diversity

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Ensuring quality of service for image transmission: Hybrid loss protection

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2004年第6期13卷 751-757页

作者： Grangetto, M Magli, E Olmo, G Politecn Torino Dipartimento Elettron Ctr Multimedia Radio Commun CERCOM I-10129 Turin Italy

We present hybrid loss protection as a new channel coding and packetization scheme for image transmission over nonprioritized lossy packet networks. The scheme employs an interleaver-based structure, and attempts to maximize the expected peak signal-to-noise ratio (PSNR) at the receiver given the constraint that the probability of failure, i.e., the probability that the PSNR of the decoded image is below a given threshold, is upper-bounded by a user-defined value. A new code-allocation algorithm is proposed, which employs Gilbert-Elliot modeling of the network statistics. Experimental results are provided in the case of transmission of images encoded by SPIHT and JPEG 2000 over a wireline, as well as a wireless UNITS-based Internet connection.

关键词： image transmission joint source and channel coding JPEG 2000 multiple description coding quality of service SPIHT unequal loss protection

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Subspace algorithms for error localization with quantized DFT codes

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IEEE TRANSACTIONS ON COMMUNICATIONS 2004年第12期52卷 2115-2124页

作者： Rath, G Guillemot, C INRIA IRISA F-35042 Rennes France

Recently, a class of real-number Bose-Chaudbuiri-Hocquengem codes known as discrete Fourier transform (DFT) codes have been considered as joint source and channel codes for providing robustness to erasures and errors over wireless networks. In this paper, we propose three subspace algorithms for error localization with quantized DFT codes. The algorithms are similar to the MUSIC, the minimum-norm, and the ESPRIT algorithms used in. array signal processing for direction-of-arrival estimation. They provide different but related formulations of the error localizations by first partitioning a vector space into the channel error subspace and its orthogonal complement, the noise subspace. The locations of the errors are determined from either the error subspace eigenvectors or the. noise subspace eigenvectors. We also present a brief performance analysis of the localization error in terms of the perturbation of the error subspace due to quantization. Simulation results show that their localization performances are similar, and they perform better than the coding-theoretic approach over a broad range of channel-error-to-quantization-noise ratios.

关键词： discrete Fourier transform (DFT) codes error correction joint source and channel coding subspace algorithms

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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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Clustering source output bits and equalizing bit error sensitivity to improve the quality and robustness of transmitted images over wireless channels

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2003年第10期18卷 947-956页

作者： Fang, JT Shyu, WL Wu, CS Chen, KJ Natl Chung Cheng Univ Dept Elect Engn Chiayi 621 Taiwan

A joint design of source coding and channel coding is proposed to transmit images over error-prone wireless channels. First, the importance of each source output bit is quantified in bit error sensitivity (BES). Next, clustered set partitioning in hierarchical trees (C-SPIHT) is adopted to cluster SPIHT output bits so that the resultant bit-clusters have distinct BES. Then, we prove that equalizing the mean BES of bit-clusters provides the optimal assignment of channel coding rates for the unequal error protection. Besides, to achieve the best PSNR performance under a transmission rate, we use a heuristic method to allocate the source coding rate and channel coding rate. Simulation results show that, under different channel bit error rates, our design not only improves the mean PSNR performance, but also reduces the variations of PSNR performance, i.e. the robustness of PSNR to the channel noise interference is improved. (C) 2003 Published by Elsevier B.V.

关键词： wireless multimedia communications joint source and channel coding rate-distortion bit error sensitivity unequal error protection

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A unified architecture for real-time video-coding systems

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 2003年第6期13卷 472-487页

作者： Li, ZG Zhu, C Ling, N Yang, XK Feng, GN Wu, S Pan, F Inst InfoComm Res Div Med Singapore 119613 Singapore Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Santa Clara Univ Dept Comp Engn Santa Clara CA 95053 USA

This paper presents a unified architecture for a live video over the Internet with emphasis on solving some challenging problems such as network bandwidth adaptation for rate and congestion, loss packet recovery, joint source and channel coding, and packetization. In our architecture, a time-varying bit rate for the source coding and time-varying ratios for the channel coding are simultaneously computed by a new congestion-control protocol. An adaptive rate-control scheme is then proposed to calculate quantization parameters and to determine the number of skipping frames corresponding to the bit rate. An adaptive unequal error-control scheme is also provided to protect the bitstream. Furthermore, a simple and MPEG-4 standard compatible algorithm is designed to packetize generated bitstream at the SyncLayer by using the existing resynchronization marker approach. With the proposed architecture, the coding efficiency and the robustness of the whole system are improved greatly.

关键词： adaptive rate control congestion control joint source and channel coding packetization unequal error control video over the Internet

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Corrupted video quality analysis of Error-Resilient 3-D SPIHT vs. MPEG-2

Corrupted video quality analysis of Error-Resilient 3-D SPIH...

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Conference on Visual Information Processing XII

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

ISBN: (纸本)0819449687

A great deal of digital video quality measurement research has been performed to quantify human visual perception with compressed video clips. Since transmitted video quality is heavily dependent on the bit-rate, error rate and dropped packet rate, a new measurement paradigm is required to analyze the corrupted video. Fast eigen-based video quality metric (VQM) and visualization techniques have been developed to measure and analyze the corrupted video qualities objectively. 3-D SPIHT and MPEG-2 with for-ward error correction (FEC) had been tested over a Video CODEC RF Test-bed. The experimental results indicate that the proposed scheme is useful for a low complexity VQM.

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

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