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Dynamic peer buffer adjustment to improve service availability on peer-to-peer on-demand streaming networks

PEER-TO-PEER NETWORKING AND APPLICATIONS 2014年第1期7卷 1-15页

作者： Lin, Chow-Sing Yan, Meng-Jia Natl Univ Tainan Dept Comp Sci & Informat Engn Tainan 70005 Taiwan

In general, on-demand video services enable clients to watch videos from beginning to end. As long as clients are able to buffer the initial part of the video they are watching, on-demand service can provide access to the video to the next clients who request to watch it. Therefore, the key challenge is how to keep the initial part of a video in a peer's buffer for as long as possible, and thus maximize the service availability of a video for stream relay. In our previous research work, we proposed a novel caching scheme for peer-to-peer on-demand streaming, called Dynamic Buffering. The dynamic buffering relies on the feature of multiple description coding to gradually reduce the number of cached descriptions held in a peer's buffers, once the buffer is full. In this paper, we proposed three description dropping policies for dynamic buffering, called sequence dropping, m-dropping, and binary dropping. In addition, mathematical formulas of the reduced number of buffer adjustments of descriptions and the reduction of the average number of selectable descriptions for m-dropping and binary dropping by factors of the number of receiving descriptions (n) and the number of discarded descriptions (m) are established. Experimental results showed that the m-dropping, generally outperformed m-dropping, and binary dropping in terms of service availability. Even though the accumulated reduction of buffer adjustments for m-dropping policies was less than that for binary dropping, the average number of selectable descriptions for m-dropping was much greater than that for binary dropping. Furthermore, Compared with the sequence dropping, the m-dropping, , would have much less number of buffer adjustments with little difference of the number of selectable descriptions.

关键词： Dynamic buffering Service availability multiple description coding Peer-to-peer Streaming

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Non-Asymptotic Converse Bounds and Refined Asymptotics for Two Source coding Problems

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IEEE TRANSACTIONS ON INFORMATION THEORY 2019年第10期65卷 6414-6440页

作者： Zhou, Lin Motani, Mehul Natl Univ Singapore Dept Elect & Comp Engn Singapore 117583 Singapore Univ Michigan Dept Elect Engn & Comp Sci Ann Arbor MI 48109 USA

In this paper, we revisit two multi-terminal lossy source coding problems: the lossy source coding problem with side information available at the encoder and one of the two decoders, which we term as the Kaspi problem (Kaspi, 1994), and the multiple description coding problem with one semi-deterministic distortion measure, which we refer to as the Fu-Yeung problem (Fu and Yeung, 2002). For the Kaspi problem, we first present the properties of optimal test channels. Subsequently, we generalize the notion of the distortion-tilted information density for the lossy source coding problem to the Kaspi problem and prove a non-asymptotic converse bound using the properties of optimal test channels and the well-defined distortion-tilted information density. Finally, for discrete memoryless sources, we derive refined asymptotics which includes the second-order, large, and moderate deviations asymptotics. In the converse proof of second-order asymptotics, we apply the Berry-Esseen theorem to the derived non-asymptotic converse bound. The achievability proof follows by first proving a type-covering lemma tailored to the Kaspi problem, then properly Taylor expanding the well-defined distortion-tilted information densities and finally applying the Berry-Esseen theorem. We then generalize the methods used in the Kaspi problem to the Fu-Yeung problem. As a result, we obtain the properties of optimal test channels for the minimum sum-rate function, a non-asymptotic converse bound and refined asymptotics for discrete memoryless sources. Since the successive refinement problem is a special case of the Fu-Yeung problem, as a by-product, we obtain a non-asymptotic converse bound for the successive refinement problem, which is a strict generalization of the non-asymptotic converse bound for successively refinable sources (Zhou, Tan, and Motani, 2017).

关键词： Lossy source coding multiple description coding non-asymptotic converse bound second-order asymptotics large deviations moderate deviations

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Source-channel diversity for parallel channels

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IEEE TRANSACTIONS ON INFORMATION THEORY 2005年第10期51卷 3518-3539页

作者： Laneman, JN Martinian, E Wornell, GW Apostolopoulos, JG Univ Notre Dame Dept Elect Engn Notre Dame IN 46556 USA Mitsubishi Elect Res Labs Cambridge MA 02139 USA MIT Dept Elect Engn & Comp Sci Cambridge MA 02139 USA Hewlett Packard Labs Palo Alto CA 94304 USA

We consider transmitting a source across a pair of independent, nonergodic channels with random states (e.g., slow-fading channels) so as to minimize the average distortion. The general problem is unsolved. Hence, we focus on comparing two commonly used source and channel encoding systems which correspond to exploiting diversity either at the physical layer through parallel channel coding or at the application layer through multiple description (MD) source coding. For on-off channel models, source coding diversity offers better performance. For channels with a continuous range of reception quality, we show the reverse is true. Specifically,. we introduce a new figure of merit called the distortion exponent which measures how fast the average distortion decays with signal-to-noise ratio. For continuous-state models such as additive white Gaussian noise (AWGN) channels with multiplicative Rayleigh fading, optimal channel coding diversity at the physical layer is more efficient than source coding diversity at the application layer in that the former achieves a better distortion exponent. Finally, we consider a third decoding architecture: MD encoding with joint source-channel decoding. We show that this architecture achieves the same distortion exponent as systems with optimal channel coding diversity for continuous-state channels, and maintains the advantages of MD systems for on-off channels. Thus, the MD system with joint decoding achieves the best performance from among the three architectures considered, on both continuous-state and on-off channels.

关键词： application layer diversity diversity joint source-channel coding multiple description coding parallel channels

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M-description Lattice Vector Quantization: Index Assignment and Analysis

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2009年第6期57卷 2258-2274页

作者： Liu, Minglei Zhu, Ce Chongqing Univ Posts & Telecommun Sch Commun & Informat Engn Chongqing 400065 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

In this paper, we investigate the design of symmetric entropy-constrained multiple description lattice vector quantization (MDLVQ), more specifically, MDLVQ index assignment. We consider a fine lattice containing clean similar sublattices with S-similarity. Due to the S-similarity of the sublattices, an M-fraction lattice can be used to regularly partition the fine lattice with smaller Voronoi cells than a sublattice does. With the partition, the MDLVQ index assignment design can be translated into a transportation problem in operations research. Both greedy and general algorithms are developed to pursue optimality of the index assignment. Under high-resolution assumption, we compare the proposed schemes with other relevant techniques in terms of optimality and complexity. Following our index assignment design, we also obtain an asymptotical close-form expression of k-description side distortion. Simulation results on coding different sources of Gaussian, speech and image are presented to validate the effectiveness of the proposed schemes.

关键词： Index assignment lattice lattice vector quantization multiple description coding sublattice transportation problem

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Two-stage multiple description image coders: Analysis and comparative study

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SIGNAL PROCESSING-IMAGE COMMUNICATION 2006年第8期21卷 609-625页

作者： Norkin, Andrey Gotchev, Atanas Egiazarian, Karen Astola, Jaakko Tampere Univ Technol Inst Signal Proc FIN-33101 Tampere Finland

A general two-stage multiple description coding (MDC) scheme using whitening transform is analyzed. It represents the original image in a form of a coarse image approximation and a residual image. The coarse approximation is subsequently duplicated and combined with the residual image further split into two descriptions using a checkerboard block transform coefficients rearrangement. We identify the importance of a good coarse approximation and explore different approaches for changing its resolution and coding it. We also propose different approaches for coding the residual signal. The coder scheme is quite simple and yet achieves high performance comparable with other MDC methods. (C) 2006 Elsevier B.V. All rights reserved.

关键词： multiple description coding error resilience bit allocation

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A high quality image reconstruction method based on nonconvex decoding

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Science China(Information Sciences) 2013年第11期56卷 184-193页

作者： ZHAO GuangHui SHEN FangFang WANG ZhengYang WU WeiJia SHI GuangMing LIU DanHua School of Electronic Engineering Xidian University

The article proposes a fast reconstruction algorithm for l0≤p≤1 norm nonconvex model,called Gradient projection nonconvex sparse recovery(GPNSR),which makes a good performance in high-quality image *** apply the GPNSR into canonical multiple description coding theory and propose a robust high-quality compressed sensing-based coding *** with iterative weighted technique and fast gradient descent method,the proposed method implicitly implements matrix inverse operations to highly reduce the storage *** the weighted norm method is taken to optimize the descent steps,which highly increases convergent speed of the *** an image has sparse Fourier representations as an example,the paper presents the detailed image sparse coding and fast reconstruction *** integrating the compressive sensing multi-description coding framework,the simulation demonstrates the superior reconstruction performance of the proposed *** importantly,with p close to zero,the reconstruction performance of GPNSR can approximate that of l0 norm optimization result.

关键词： l0≤p≤1 norm nonconvex decoding multiple description coding iteration weighting

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Iterative decoding of differentially space-time coded multiple descriptions of images

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IEEE SIGNAL PROCESSING LETTERS 2004年第8期11卷 686-689页

作者： Sun, Y Xiong, ZX Wang, XD Texas A&M Univ Dept Elect Engn College Stn TX 77843 USA Columbia Univ Dept Elect Engn New York NY 10027 USA

We consider transporting images over wireless fading channels rather than the on-off channels considered in most works related to multiple description (MD) coding. The new idea is to use iterative (turbo) decoding techniques developed for serially concatenated coding systems to improve the performance of the receiver in successive decoding iterations. We treat MD coding, realized by embedded image coding plus unequal error protection (e.g., product code structure), as the outer constituent code and use a differential space-time code as the inner constituent code. Experimental results show that our iterative scheme can effectively improve the system performance. Furthermore, most of the gain in PSNR is achieved with only one iteration in the low SNR range, e.g., 0-20 dB.

关键词： differential space-time coding image transmission iterative decoding multiple description coding wireless fading channel

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The orchard algorithm building multicast trees for P2P video multicasting without free-riding

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IEEE TRANSACTIONS ON MULTIMEDIA 2007年第8期9卷 1593-1604页

作者： Mol, Jan David Epema, Dick H. P. Sips, Henk J. Delft Univ Technol Dept Comp Sci NL-2628 CD Delft Netherlands

The main purpose of many current peer-to-peer (P2P) networks is off-line file sharing. However, a potentially very promising use of such networks is to share video streams (e.g., TV programs) in real time. In order to do so, the peers in a P2P network who are interested in the same video stream may employ Application Level Multicasting (ALM). In existing P2P networks, peers may exhibit behavior which is problematic for ALM: they are not always willing to donate! resources (free-riding), and they may arrive and depart at a high rate (churn). In this paper we propose the Orchard algorithm for creating and maintaining ALM trees in P2P networks, which deals with both these problems. By employing a technique called multiple description coding, we split a video stream into several substreams. Orchard creates a dynamic spanning tree for each of these substreams in such a way that in the resulting forest, no peer has to forward more substreams than it receives. Based on an analysis of the expected performance of Orchard and on experiments in a real system, we find that Orchard is capable of maintaining a multicast forest, even when peers join and leave the forest at a high rate.

关键词： distributed algorithms free-riding multicast channels multiple description coding peer-to-peer

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Maximum minimal distance partitioning of the Z² lattice

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IEEE TRANSACTIONS ON INFORMATION THEORY 2003年第4期49卷 981-992页

作者： Bajic, IV Woods, JW Rensselaer Polytech Inst Dept Syst & Comp Engn Ctr Image Proc Res & Elect Troy NY 12180 USA

We study the problem of dividing the Z(2) lattice into partitions so that minimal intra-partition distance between the points is maximized. We show that this problem is analogous to the problem of sphere packing. An upper bound on the achievable intra-partition distances for a given number of partitions follows naturally from this observation, since the optimal sphere packing in two dimensions is achieved by the hexagonal lattice. Specific instances of this problem, when the number of partitions is 2, were treated in trellis-coded modulation (TCM) code design by Ungerboeck and others. It will be seen that methods previously used for set partitioning in TCM code design are asymptotically suboptimal as the number of partitions increases. We propose an algorithm for solving the Z(2) lattice partitioning problem for an arbitrary number of partitions.

关键词： lattice partitioning multiple description coding set partitioning trellis-coded modulation (TCM)

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Optimized mesh routing with intermediate recovery for error resilient delivery of MD coded image/video content

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COMPUTER COMMUNICATIONS 2018年 118卷 148-162页

作者： Singhal, Chetna De, Swades Moravapalle, Uma Parthavi IIT Kharagpur Dept Elect & Elect Commum Engn Kharagpur W Bengal India IIT Delhi Dept Elect Engn New Delhi India IIT Delhi Bharti Sch Telecom New Delhi India Georgia Inst Technol Dept Elect & Comp Engn Atlanta GA 30332 USA

multiple description (MD) source coding is a technique that breaks a media stream into equally important sub streams which can be sent over different paths for protection against wireless channel errors. In this paper, we explore the possibility of sending these descriptions through different paths that merge at some specific intermediate nodes, where the corrupted descriptions are recovered from the uncorrupted ones, thereby increasing the quality of received image/video at the destination. To quantify the gain with intermediate recovery, we first devise an analytic model with simplifying assumptions on the network system for quantifying end-to-end distortion of MD coded data as a function of path parameters, and demonstrate that on a Lena image transmitted over long multipath routes, one intermediate recovery stage offers up to 9.2% reduction in distortion compared to the traditional multipath transport. Next, accounting the random network topology we formulate mesh route construction as a cross-layer optimization problem to balance between end-to-end packet delivery delay and distortion. Since this problem is highly complex, we propose two alternative delay/distortion minimization heuristics. Further, a jointly delay and distortion optimizing genetic algorithm based meta-heuristic route construction technique is suggested for networks with highly varying link quality. NS2-based simulations of a realistic network scenario demonstrate that, in terms of peak signal-to-noise ratio the intermediate recovery approach results in substantial improvement, close to 15 dB, in quality of video delivery.

关键词： multiple description coding Multipath routing Intermediate recovery Multihop wireless networks Genetic algorithm Cross layer optimization

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