multiple description coding (MDC) of video is a useful technique for robust video transmission over unreliable networks. MDC not only provides at least acceptable quality of video in error-prone network but it also ef...
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ISBN:
(纸本)9781424414369
multiple description coding (MDC) of video is a useful technique for robust video transmission over unreliable networks. MDC not only provides at least acceptable quality of video in error-prone network but it also efficiently utilizes the multipath nature of internet and wireless networks. In this paper, multipledescription video coding with 3-D Set Partitioning in Hierarchical Tree (3D-SPIHT) codec has been proposed. In particular, we propose branch-pruning technique to generate multipledescriptions. We then propose a new tree structure for 3D-SPIHT which is particularly efficient for MDC. Experimental results prove the effectiveness of the proposed method.
multiple description coding is a source coding technique that produces several descriptions of a single information source, such that various reconstruction qualities are obtained from different subsets of the descrip...
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multiple description coding is a source coding technique that produces several descriptions of a single information source, such that various reconstruction qualities are obtained from different subsets of the descriptions. It thus can provide error resilience to information transmitted on lossy networks. Among previous works, MDs for image coding were generated via polyphase transform and selective quantization, performed in the wavelet domain. In this pa- per, we present an effective way to exploit the special statistical properties of the wavelet decomposition to provide improved coding efficiency, in the same general framework. We propose a novel coding scheme that efficiently utilizes contextual information, extracted from another polyphase component, to improve the coding efficiency of each redundant component. Our experimental results demonstrate that the proposed coder outperforms its predecessor across the entire redundancy range, and that the improvement in coding efficiency can indeed be attributed primarily to the effective utilization of contextual information.
For state estimation over a communication network, efficiency and reliability of the network are critical issues. The presence of packet dropping and communication delay can greatly impair our ability to measure and p...
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For state estimation over a communication network, efficiency and reliability of the network are critical issues. The presence of packet dropping and communication delay can greatly impair our ability to measure and predict the state of a dynamic process. In this paper, multipledescription (MD) codes, a type of network source codes, are used to compensate for this effect on Kalman filtering. We consider two packet dropping models: in one model, packet dropping occurs according to an independent and identically distributed (i.i.d.) Bernoulli random process and in the other model, packet dropping is bursty and occurs according to a Markov chain. We show that MD codes greatly improve the statistical stability and performance of Kalman filter over a large set of packet loss scenarios in both cases. Our conclusions are verified by simulation results. (C) 2006 Elsevier Ltd. All rights reserved.
Real-time delivery of video over best-effort error-prone packet networks requires scalable erasure-resilient compression systems in order to 1) meet the users' requirements in terms of quality, resolution, and fra...
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Real-time delivery of video over best-effort error-prone packet networks requires scalable erasure-resilient compression systems in order to 1) meet the users' requirements in terms of quality, resolution, and frame-rate;2) dynamically adapt the rate to the available channel capacity;and 3) provide robustness to data losses, as retransmission is often impractical. Furthermore, the employed erasure-resilience mechanisms should be scalable in order to adapt the degree of resiliency against transmission errors to the varying channel conditions. Driven by these constraints, we propose in this paper a novel design for scalable erasure-resilient video coding that couples the compression efficiency of the open-loop architecture with the robustness provided by multiple description coding. In our approach, scalability and packet-erasure resilience are jointly provided via embedded multipledescription scalar quantization. Furthermore, a novel channel-aware rate-allocation technique is proposed that allows for shaping on-the-fly the output bit rate and the degree of resiliency without resorting to channel coding. As a result, robustness to data losses is traded for better visual quality when transmission occurs over reliable channels, while erasure resilience is introduced when noisy links are involved. Numerical results clearly demonstrate the advantages of the proposed approach over equivalent codec instantiations employing 1) no erasure-resilience mechanisms, 2) erasure-resilience with nonscalable redundancy, or 3) data-partitioning principles.
This paper presents TURINstream, a novel P2P video streaming architecture designed to jointly achieve low delay, robustness to peer churning, limited protocol overhead, and quality-of-service differentiation based on ...
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This paper presents TURINstream, a novel P2P video streaming architecture designed to jointly achieve low delay, robustness to peer churning, limited protocol overhead, and quality-of-service differentiation based on peers cooperation. Separate control and video overlays are maintained by peers organized in clusters that represent sets of collaborating peers. Clusters are created by means of a distributed algorithm and permit the exploitation of the participant nodes upload capacity. The video is conveyed with a push mechanism by exploiting the advantages of multiple description coding. TURINstream design has been optimized through an event driven overlay simulator able to scale up to tens of thousands of peers. A complete prototype of TURINstream has been developed, deployed, and tested on PlanetLab. We tested our prototype under varying degree of peer churn, flash crowd arrivals, sudden massive departures, and limited upload bandwidth resources. TURINstream fulfills our initial design goals, showing low average connection, startup, and playback delays, high continuity index, low control overhead, and effective quality-of-service differentiation in all tested scenarios.
In this paper, we address the problem of video multicast over Ad hoc wireless networks. Multicasting is an efficient means of one-to-many communication and is typically implemented by creating a multicast tree. Video ...
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In this paper, we address the problem of video multicast over Ad hoc wireless networks. Multicasting is an efficient means of one-to-many communication and is typically implemented by creating a multicast tree. Video multicasting demands high quality of service with a continuous delivery to receivers. However, most of the existing multicast solutions do not guarantee this because they are not resilient to mobility of the nodes and do not exploit error-resilient nature of recently available video coding techniques. Uninterrupted video transmission requires continuous reachability to receivers which emphasizes the usage of path-diversity. Hence, we propose a multiple tree multicast protocol which maintains maximally node-disjoint multicast trees in the network to attain robustness against path breaks. We further enhance the robustness by using the error-resilient multiple description coding (MDC) for video encoding. We prove that finding a given number of node-disjoint multicast trees for a multicast session in a given network is NP-Hard. Then we propose a protocol called K-Tree which maintains the maximal node-disjointedness property of K trees by using a distributed online heuristic. Through extensive simulation experiments, we show how the proposed protocol improves the video quality as we use two or three trees instead of a single tree for multicasting video stream. We also show, through simulations, that the protocol efficiently, in terms of overhead, provides high quality video as compared to an existing two tree video multicast protocol and a well known mesh-based multicast protocol. (C) 2010 Elsevier B.V. All rights reserved.
multiple description coding (MDC) makes use of redundant representations of multimedia data to achieve resiliency. descriptions should be generated so that the quality obtained when decoding a subset of them only depe...
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multiple description coding (MDC) makes use of redundant representations of multimedia data to achieve resiliency. descriptions should be generated so that the quality obtained when decoding a subset of them only depends on their number and not on the particular received subset. In this paper, we propose a method based on the principle of encoding the source at several rates, and properly blending the data encoded at different rates to generate the descriptions. The aim is to achieve efficient redundancy exploitation, and easy adaptation to different network scenarios by means of fine tuning of the encoder parameters. We apply this principle to both JPEG 2000 images and H.264/AVC video data. We consider as the reference scenario the distribution of contents on application-layer overlays with multiple-tree topology. The experimental results reveal that our method favorably compares with state-of-art MDC techniques.
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 receptio...
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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.
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 f...
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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.
This paper proposes a multiple description coding scheme based on a multi-loop structure, which prevents drift distortion accumulation in intra predicted slices. The drift is compensated by generating a controlled amo...
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ISBN:
(纸本)9781424456536
This paper proposes a multiple description coding scheme based on a multi-loop structure, which prevents drift distortion accumulation in intra predicted slices. The drift is compensated by generating a controlled amount of side information used by the decoder whenever any description is lost in the corresponding network path. The experimental results show that intra predicted slices do not suffer from drift and their quality is significantly improved (e.g., 6-8 dB) at reduced redundancy cost, (e.g., 0.2-0.25), in comparison with the open loop implementation. Error propagation in subsequent frames is also evaluated when one description is lost for a whole frame and for two rows of macroblocks. In both cases the overall video quality is significantly improved and considering normal GOP sizes the redundancy introduced by the proposed scheme is negligible.
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