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Robust and Scalable P2P Live Streaming

Journal of Donghua University(English Edition) 2009年第5期26卷 482-488页

作者：陈锬熊馨 State Key Laboratory of Software Development Environment School of Computer Science and EngineeringBeijing University of Aeronautics and Astronautics College of Computer Sciences Beijing University of Technology College of Computer and Communication Engineering Zhengzhou Institute of Light Industry

Distributing real-time video stream in large scale group communication over Interuet poses several challenging problems due to the complex network dynamics, stringent requirement of delay and loss. This paper proposes a novel peer-to-peer scheme, named TeamCast, to combat with these issues. Constructing multiple diverse application layer multicast （ALM） trees to transmit multiple independent complementary descriptions produced by multiple description coding （MDC） simultaneously, TeamCast improves error resilient ability in the presence of various levels of packet loss caused by unpredictable congestion of Internet and node failure, as well as enlarges system capacity. The results of extensive simulations indicate that TeamCast achieves low latency, scalability, and fault tolerance for the delivery of live media stream.

关键词： path diversity multiple description coding application layer multicast media streaming topologyuware

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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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A GAME THEORY BASED CLASSIFICATION FOR DISTRIBUTED DOWNLOADING OF multiple description CODED VIDEO

A GAME THEORY BASED CLASSIFICATION FOR DISTRIBUTED DOWNLOADI...

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16th IEEE International Conference on Image Processing

作者： Milani, S. Calvagno, G. Univ Padua Dept Informat Engn I-35131 Padua Italy

ISBN: (纸本)9781424456536

Recent works have shown how multiple description coding (MDC) proves to be an effective solution for the multimedia transmission over Peer-to-Peer and Content Delivery Networks. However, despite the flexibility and scalability of these novel transmission paradigms, packet streams are still affected by losses, and an effective packet labelling that differentiates the QoS levels for the transmitted data is required. The paper presents a Game Theory based approach to classify the MDC coded video packets that are downloaded from a set of terminals spread throughout the network. The proposed approach improves the quality of the reconstructed sequence with limited feedback information from the network.

关键词： multiple description coding game theory packet classification Content Delivery Network Peer-to-Peer network

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Adaptive Inter-Frame Interleaving for Cross-Layer Diversity Techniques in Multimedia Transmission

Adaptive Inter-Frame Interleaving for Cross-Layer Diversity ...

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3rd International Conference on Signal Processing and Communication Systems

作者： Toni, Laura Rossi, Lorenzo Fontaine, Jean-Guy Italian Inst Technol TERA Lab Genoa Italy

ISBN: (纸本)9781424444731

In multimedia transmission over wireless channel, cross-layer diversity techniques, able to take advantage of both application and physical layer diversity, highly improve the overall system performance. Although the optimization of source and channel coding to the diversity orders available from the channel can deeply improve the system performance, low quality image are received at the decreasing of these diversity orders. In this work, we propose an adaptive interleaving technique able to increase the cross-layer diversity gain in the transmission of embedded images/video bitstream over orthogonal frequency diversity multiplexing systems. We construct multiple independent descriptions using a FEC-based strategy, and we analyze the interleaver depth optimization based on the diversity order available in both time and frequency domain. Then, we provide results of the proposed method, and we demonstrate its superior performance in progressive image transmissions. Finally we extend the inter-frame interleaver technique to video transmission in multiuser scenario. The flexibility of the method is able to increase the cross-layer diversity gain, meeting in the meanwhile each user requirements.

关键词： Inter-frame interleaver cross-layer design frequency diversity time diversity multimedia communications multiple description coding orthogonal frequency division multiplexing (OFDM) progressive transmission wireless video

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Coded Wireless Video Broadcast/Multicast

Coded Wireless Video Broadcast/Multicast

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作者： She, James University of Waterloo

学位级别：master

Advancements in video coding, compact media display, and communication devices, particularly in emerging broadband wireless access networks, have created many foreseeable and exciting applications of video broadcast/multicast over the wireless meidum. For efficient and robust wireless video broadcast/multicast under fading, this thesis presents and examines a novel cross-layer framework that exploits the interplay between applying protections on a successively refinable video source and transmitting through a layered broadcast/multicast channel. The framework is realistically achieved and evaluated by using multiple description coding (MDC) on a scalable video source and using superposition coding (SPC) for layered broadcast/multicast transmissions. An analytical model using the total received/recovered video bitstreams from each coded wireless broadcast/multicast signal is developed, which serves as a metric of video quality for the system analysis and optimization. An efficient methodology has demonstrated that optimal power allocations and modulation selections can be practically determined to improve the broadcast/multicast video quality. From the information-theoretical perspective, a general closed-form formula is derived for the end-to-end distortion analysis of the proposed framework, which is applicable to any (n, k) protection code applied on a successive refinable source with a Gaussian distribution over layered Gaussian broadcast channels. The results reveal the scenarios for the proposed framework to lead to a lower distortion than a legacy system without any protection. By analyzing the characteristics of the closed-form formula, an efficient O(n log n) algorithm is developed to determine optimal k values in the (n, k) protection codes that minimize the distortion under the framework. Finally, a cross-layer design of logical SPC modulation is introduced to achieve layered broadcast/multicast for scalable video. It serves as an alternative for practical

关键词： wireless video broadcast/multicast cross-layer design successive refinement gaussian broadcast channel multiple description coding protection

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Optimal Power Allocation for a Successive Refinable Source with multiple descriptions over a Fading Relay Channel Using Broadcast/Multicast Strategies

Optimal Power Allocation for a Successive Refinable Source w...

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作者： Shi, Kun University of Waterloo

学位级别：master

In a wireless fading relay system with multicast/broadcast transmission, one of the most crucial challenges is the optimization of a transmission rate under multiuser channel diversity. Previously reported solutions for mitigating the vicious effect due to multi-user channel diversity have been mainly based on superposition coded multicast, where an optimal power allocation to each layer of modulated signals is determined. Many previous studies investigated a harmonic interplay between the successively re nable (SR) content source and a layered modulation via superposition coding (SPC) over the multicast/broadcast channels. By jointly considering the successive re nement characteristic at the source and the dependency of the layered modulation at the channel, a graceful fexibility can be achieved on a group of users with di erent channel realizations. Here most of the receivers are supposed to obtain the base quality layer information modulated in a lower rate, while the receivers with better channel realizations will obtain more information by re ning the base quality layer information using the enhancement quality layer information. In particular, the optimal power allocation for a SR source over a fading relay channel using broadcast/multicast strategy can be determined such that the minimum distortion of total received information is ***, a quality layer of data in a successively refined source may not be decodable if there is any loss of channel codewords, even if the corresponding longterm channel realization is su cient for decoding. To overcome this problem, one of the previous studies introduced a framework of coded video multicast, where multiple description coding (MDC) is applied to an SR content source and is further mapped into a layered modulation via SPC at the channel. Up till now, there has not been a rigorous proof provided on the bene t of manipulating the two coding techniques, (i.e. MDC and SPC), nor has any systematic optimization

关键词： power allocation multiple description coding relay channel broadcast/multicast strategy

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FEC-based scalable multiple description coding for overlay network streaming

FEC-based scalable multiple description coding for overlay n...

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2nd IEEE Consumer Communications and Networking Conference

作者： Wang, GJ Futemma, S Itakura, E Information Technology Lab. Sony Japan

ISBN: (纸本)0780387848

We consider the problem of distributing video data from a server to a population of interested clients. Deploying overlay network with application-layer multicast, we propose it FEC-based scalable multiple description coding (SMDC) scheme to arrive at the solution to the problem. Without the performance penalty on each receiver, our SMDC can achieve optimal performance of each client with different net-work conditions as simply as additional assembling and truncating operations. In the mean time, a R-D allocation algorithm is presented to decide the rates of the source and channel. Simulation shows that our SMDC have better quality for heterogeneous receivers than traditional scheme.

关键词： multiple description coding overlay network scalable video streaming

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A SYSTEM FOR STREAMING MEDIA BASED ON SYNCHRONIZED multiple descriptionS coding

A SYSTEM FOR STREAMING MEDIA BASED ON SYNCHRONIZED MULTIPLE ...

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2nd IEEE International Conference on Broadband Network and Multimedia Technology

作者： Zhang Youwei Wu Chanle Wuhan Univ Natl Engn Res Ctr Multimedia Software Wuhan 430072 Peoples R China

ISBN: (纸本)9781424450053

Nowadays, many application layer multicast protocols (ALM) in which multiple description coding (MDC) is introduced have been proved to be more scalable and stable than traditional multicast protocols in practical environment. In this paper, we propose an ALM system called SMSD based on synchronized MDC for streaming media to address the synchronization of available descriptions. SMSD focuses on the video quality, firstly hosts can join the different overlay trees in different layers simultaneously, then the maximum covering set is worked out based on acquired descriptions information to achieve the best video quality, the quality management module with much low overhead is responsible for monitoring the variation of cached content due to departure of parents and activating the re-join procedure. Simulations implemented on Internet-like topology indicate that SMSD achieves higher video quality, lower control traffic than traditional ALM protocols, and comparable latency, link stress and robustness are achieved as well.

关键词： application layer multicast overlay tree streaming media synchronization video quality multiple description coding

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Channel coding for Progressive Images in a 2-D Time-Frequency OFDM Block With Channel Estimation Errors

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IEEE TRANSACTIONS ON IMAGE PROCESSING 2009年第11期18卷 2476-2490页

作者： Toni, Laura Chan, Yee Sin Cosman, Pamela C. Milstein, Laurence B. Italian Inst Technol TERA Genoa Italy Univ Bologna WiLab Bologna Italy Verizon Corp Technol Walnut Creek CA 94597 USA Univ Calif San Diego Dept Elect & Comp Engn La Jolla CA 92093 USA

coding and diversity are very effective techniques for improving transmission reliability in a mobile wireless environment. The use of diversity is particularly important for multimedia communications over fading channels. In this work, we study the transmission of progressive image bitstreams using channel coding in a 2-D time-frequency resource block in an OFDM network, employing time and frequency diversities simultaneously. In particular, in the frequency domain, based on the order of diversity and the correlation of individual subcarriers, we construct symmetric n-channel FEC-based multiple descriptions using channel erasure codes combined with embedded image coding. In the time domain, a concatenation of RCPC codes and CRC codes is employed to protect individual descriptions. We consider the physical channel conditions arising from various coherence bandwidths and coherence times, leading to a range of orders of diversities available in the time and frequency domains. We investigate the effects of different error patterns on the delivered image quality due to various fade rates. We also study the tradeoffs and compare the relative effectiveness associated with the use of erasure codes in the frequency domain and convolutional codes in the time domain under different physical environments. Both the effects of intercarrier interference and channel estimation errors are included in our study. Specifically, the effects of channel estimation errors, frequency selectivity and the rate of the channel variations are taken into consideration for the construction of the 2-D time-frequency block. We provide results showing the gain that the proposed model achieves compared to a system without temporal coding. In one example, for a system experiencing flat fading, low Doppler, and imperfect CSI, we find that the increase in PSNR compared to a system without time diversity is as much as 9.4 dB.

关键词： Channel coding cross-layer design diversity multimedia communications multiple description coding orthogonal frequency division multiplexing (OFDM) progressive transmission wireless video

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multiple description SCALAR QUANTIZATION WITH SUCCESSIVE REFINEMENT

MULTIPLE DESCRIPTION SCALAR QUANTIZATION WITH SUCCESSIVE REF...

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European signal processing conference

作者： Muhammad Majid Charith Abhayaratne Department of Electronic and Electrical Engineering The University of Sheffield Sheffield SI 3JD United Kingdom

ISBN: (纸本)9781617388767

This work presents a framework for multiple description coding (MDC) based scalable image coding. The paper starts with defining the conditions for deviating from the conventional multiple description scalar quantization (MDSQ) by extending the MDSQ into multiple-channel (more than 2) unbalanced descriptions. These two conditions are extended to define the new framework for MDSQ with successive refinement. We propose that the split or refinement factor for each of the refinement side quantizers should be greater than the number of diagonals filled in the index assignment matrix of the side quantizer design and should not be integer multiples of each other, in order to reduce the distortion in joint decoding when the number of descriptions included in joint decoding is increased. Proofs and verification by simulations of these propositions are are shown in the paper. Experimental results show high robustness of the proposed scheme compared to single description scalable image coding.

关键词： image coding integer multiple Quantization quantizer Refining scalar quantization Scalability DEcoding Frameworks MULTICHANNEL Diagonal multiple description coding

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