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Permuted smoothed descriptions and refinement coding for images

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2000年第6期18卷 915-926页

作者： Ridge, J Ware, FW Gibson, JD So Methodist Univ Dept Elect Engn Dallas TX 75275 USA Texas A&M Univ College Stn TX USA

We consider the problem of transmitting compressed still images over lossy channels. In particular, we examine the situation where the data stream is partitioned into two independent channels, as is often considered in the multiple descriptions approach to image compression. In this paper, we introduce a coder design called smoothed descriptions, which matches a data partitioning method utilized at the encoder to the error concealment technique employed at the decoder. This approach has the advantage of inserting minimal overhead into the transmitted data streams, so that system performance is undiminished when there are no packet losses over the channel, We show that, by using a combination of DC averaging and maximal smoothing to conceal errors, performance comparable to or better than multiple descriptions can be achieved for packet loss rates up to 5%. By adding a feedback loop that requests retransmission of important data, we also demonstrate the need to exploit latency whenever possible.

关键词： error resiliency image compression image partitioning multiple description coding robustness

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Robust Multiresolution coding

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IEEE TRANSACTIONS ON COMMUNICATIONS 2010年第11期58卷 3186-3195页

作者： Chen, Jun Dumitrescu, Sorina Zhang, Ying Wang, Jia McMaster Univ Dept Elect & Comp Engn Hamilton ON L8S 4K1 Canada Shanghai Jiao Tong Univ Dept Elect Engn Shanghai 200240 Peoples R China

In multiresolution coding a source sequence is encoded into a base layer and a refinement layer. The refinement layer, constructed using a conditional codebook, is in general not decodable without the correct reception of the base layer. By relating multiresolution coding with multiple description coding, we show that it is in fact possible to construct multiresolution codes in certain ways so that the refinement layer alone can be used to reconstruct the source to achieve a nontrivial distortion. As a consequence, one can improve the robustness of the existing multiresolution coding schemes without sacrificing the efficiency. Specifically, we obtain an explicit expression of the minimum distortion achievable by the refinement layer for arbitrary finite alphabet sources with Hamming distortion measure. Experimental results show that the information-theoretic limits can be approached using a practical robust multiresolution coding scheme based on low-density generator matrix codes.

关键词： Low-density generator matrix message-passing algorithm multiple description coding multiresolution coding successive refinement

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A content-centric framework for effective data dissemination in opportunistic networks

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2008年第5期26卷 761-772页

作者： Chen, Ling-Jyh Yu, Chen-Hung Tseng, Cheng-Long Chu, Hao-hua Chou, Cheng-Fu Acad Sinica Inst Informat Sci Taipei Taiwan Natl Taiwan Univ Dept Comp Sci & Informat Engn Taipei 10764 Taiwan Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei Taiwan

In this paper, we address the challenges of content transfer in opportunistic networks, and propose techniques to better facilitate data dissemination based on the characteristics of the content. To investigate this problem from its origins, we propose three message scheduling algorithms: Sequential Forwarding (SF), Full Interleaving (FI), and Block-based Interleaving (III). Each algorithm is embedded in a specially tailored data dissemination technique to evaluate the benefits of applying it to different types of content and data dissemination methods. Three types of content (file, video and web) are considered and evaluated, and the dissemination methods considered are Layered multiple description coding (LMDC) based and file-based. Using simulations as well as both synthetic and realistic network scenarios, we evaluate the proposed schemes in terms of latency and user perceived quality, and demonstrate how the schemes can achieve much better latency performance for file transfers. Furthermore, we show that using LMDC-based techniques leads to higher user perceived quality, since the end user is allowed to "preview" video file or web content, even before the data has been completely transferred. The effectiveness and robustness of our message scheduling algorithms and their corresponding content dissemination techniques make them ideal solutions that can go a long way toward effective data dissemination in opportunistic networks.

关键词： opportunistic networks delay/disruption tolerant networks routing multiple description coding layered coding

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Energy-Efficient Video Multicast in 4G Wireless Systems

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IEEE TRANSACTIONS ON MOBILE COMPUTING 2012年第10期11卷 1508-1522页

作者： Yu, Ya-Ju Hsiu, Pi-Cheng Pang, Ai-Chun Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei 106 Taiwan Acad Sinica Res Ctr Informat Technol Innovat CITI Taipei 115 Taiwan Acad Sinica IIS Taipei 115 Taiwan Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei 106 Taiwan Natl Taiwan Univ Dept Comp Sci & Informat Engn Taipei 106 Taiwan

Layer-based video coding, together with adaptive modulation and coding, is a promising technique for providing real-time video multicast services on heterogeneous mobile devices. With the rapid growth of data communications for emerging applications, reducing the energy consumption of mobile devices is a major challenge. This paper addresses the problem of resource allocation for video multicast in fourth-generation wireless systems, with the objective of minimizing the total energy consumption for data reception. First, we consider the problem when scalable video coding is applied. We prove that the problem is NP-hard and propose a 2-approximation algorithm to solve it. Then, we investigate the problem under multiple description coding, and show that it is also NP-hard and cannot be approximated in polynomial time with a ratio better than 2, unless P = NP. To solve this case, we develop a pseudopolynomial time 2-approximation algorithm. The results of simulations conducted to compare the proposed algorithms with a brute-force optimal algorithm and a conventional approach are very encouraging.

关键词： Energy efficiency video multicast scalable video coding multiple description coding adaptive modulation and coding 4G wireless systems

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On joint routing and server selection for MD video streaming in ad hoc networks

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2007年第1期6卷 338-347页

作者： Mao, Shiwen Cheng, Xiaolin Hou, Y. Thomas Sherali, Hanif D. Reed, Jeffrey H. Auburn Univ Dept Elect & Comp Engn Auburn AL 36849 USA Virginia Tech Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA Univ Calif Davis Dept Comp Sci Davis CA 95616 USA Virginia Tech Grado Dept Ind & Syst Engn Blacksburg VA 24061 USA

For media streaming in ad hoc networks, service replication has been demonstrated to be a quite effective countermeasure to streaming interruptions caused by fragile-paths and dynamic topology. In this paper, we study the problem of joint routing and server selection for double description (DD) video streaming in ad hoc networks. We formulate the task as a combinatorial optimization problem and present tight lower and upper bounds for the achievable distortion. The upper bound provides a feasible solution to the formulated problem. Our extensive numerical results show that the bounds are very close to each other for all the cases studied, indicating the near-global optimality of the derived upper bounding solution. Moreover, we observe significant gains in video quality achieved by the proposed approach over existing server selection schemes. This justifies the importance of jointly considering routing and server selection for optimal MD video streaming.

关键词： ad hoc network multiple description coding routing video streaming server diversity

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A fine-grained balancing scheme for improved scalability in P2P streaming

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MULTIMEDIA TOOLS AND APPLICATIONS 2010年第1期46卷 71-90页

作者： Lin, Chow-Sing Syu, Wei-Ting Natl Univ Tainan Dept Comp Sci & Informat Engn Tainan 700 Taiwan So Taiwan Univ Dept Informat Management Yung Kang 710 Tainan Shien Taiwan

In this paper, we relax the restriction imposed in our previously proposed balancing scheme that a peer is allowed to forward only one specific description to others, and propose the fine-grained balancing scheme to further improve the scalability of P2P live streaming systems based on multiple description coding (MDC) techniques. Like the balancing scheme, the fine-grained balancing scheme is capable of balancing the distribution of descriptions and streaming workload among peers by means of a centralized description allocation scheme. Moreover, relaxing the restriction on peers' description provision enables the proposed fine-grained balancing scheme to utilize peers' outbound bandwidth more flexibly and efficiently than the balancing scheme. The experiment results show that with the proposed scheme the utilization of peers' bandwidth can be greatly improved, thereby reducing the server bandwidth consumption and the rejection rate. As a result, more peers can be served and peers are enabled to recover from failure mostly by themselves with little server involvement.

关键词： Peer-to-peer Streaming multiple description coding Load balancing Scalability

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Optimal correlating transform for erasure channels

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IEEE SIGNAL PROCESSING LETTERS 2005年第10期12卷 677-680页

作者： Romano, G Rossi, PS Palmieri, F Univ Naples 2 Dipartimento Ingn Informaz I-81031 Aversa CE Italy Univ Naples Federico II Dipartimento Informat & Sistemist I-80125 Naples Italy

In this letter, we derive a gradient-based algorithm for computing the optimal transform when coefficients are transmitted over an erasure channel whose statistics are known. The discrete transform introduces correlation among the coefficients with consequent performance improvement against losses. Simulations show appreciable improvements over standard schemes and also good robustness when loss probabilities are only roughly estimated.

关键词： erasure channel multiple description coding transform coding

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A Two-description Distributed Video coding

A Two-Description Distributed Video Coding

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The Fifth International Conference on Information Assurance and Security(第五届信息保障与安全国际会议)

作者： Anhong Wang Yao Zhao Zhihong Li Institute of Information Science Beijing Jiaotong University BeijingChina School of Electronic Information Engineering Taiyuan University of Science and Technology TaiyuanCh

ISBN: (纸本)9780769537443

In this paper, a two-description distributed video coding (2D-DVC) is proposed to address the robust video transmission of low-power captures. The odd/even framesplitting partitions a video into two subsequences to produce two descriptions. Each description consists of two parts, where part 1 is a zero-motion based H.264 coded bitstream of a subsequence and part 2 is a Wyner-Ziv coded bitstream of the other subsequence. As the redundant part, the Wyner-Ziv coded bitstream guarantees the lost subsequence is recovered when one description is lost. On the other hand, the redundancy degrades the rate-distortion performance as no loss occurs. Therefore, a residual 2D-DVC is employed to reduce the redundancy, where the difference of two subsequences is Wyner-Ziv encoded to generate the part 2 in each description. The experimental results show that the proposed schemes achieve better performance than the referenced one especially when the video motion is low. Moreover, our schemes maintain low-complexity encoding.

关键词： distributed video coding multiple description coding low-complezity encoding robust transmission

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Relay-Assisted Rateless Layered multiple description Video Delivery

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2013年第8期31卷 1629-1637页

作者： Nazir, Sajid Stankovic, Vladimir Attar, Hani Stankovic, Lina Cheng, Samuel Univ Strathclyde Dept Elect & Elect Engn Glasgow G1 1XW Lanark Scotland Univ Oklahoma Sch Elect & Comp Engn Tulsa OK 74135 USA

multiple description coding (MDC) has been proposed as a possible solution to real-time video delivery over relay-assisted wireless networks to exploit path diversity. In this paper, we study layered multiple description video over relay-assisted mobile networks, such as LTE-A, and develop a framework that routes packets to different relays based on source-channel-relay parameters. The proposed system comprises, besides layered MDC, (i) application-layer forward error correction via Random linear codes (RLC) that are very suitable in the relaying scenarios, due to their rateless nature, (ii) unequal error protection (UEP), using the recently proposed expanding window technique, that relies on probabilistic scheduling of layered packets. We generate layered multiple descriptions using data slicing and data partitioning features of H. 264/AVC and conduct simulations by modelling a two-relay LTE-A setup with the finite state Markov chain model. Simulation results show benefits of relaying with optimized routing and UEP.

关键词： Multipath video wireless relaying multiple description coding

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Layered coded vs. multiple description coded video over error-prone networks

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2003年第5期18卷 337-356页

作者： Lee, YC Kim, J Altunbasak, Y Mersereau, RM Georgia Inst Technol Sch Elect & Comp Engn Atlanta GA 30332 USA

Layered (LC) and multiple description coding (MDC) have been proposed as source coding techniques that are robust to channel errors for video transmission. LC and MDC have similar characteristics: they both generate multiple sub-bitstreams, and it is permissible to drop some portion of the data from the sub-bitstreams during transmission for both methods. However, they are different in the sense that the sub-bitstreams for LC have different levels of importance while all sub-bitstreams for MDC are equally important. Since these two encoding techniques have similar properties, some performance comparisons between LC and MDC have recently been reported. However, these studies are still not conclusive because several scenarios have not been carefully considered. Furthermore, they have been performed in different environments. In this paper, we further investigate the error-resilience capabilities of these two encoding techniques through extensive experimentation. Although some of our conclusions agree with those in the literature, we believe that this paper provides the most comprehensive performance comparison yet between LC and MDC. (C) 2003 Elsevier Science B.V. All rights reserved.

关键词： layered coding multiple description coding error-resilient video communications MPEG video

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