During the last years, video coding designers have proposed robust coding approaches that combine multiple description coding (MDC) schemes with Distributed Video coding (DVC) principles. In this way, it is possible t...
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During the last years, video coding designers have proposed robust coding approaches that combine multiple description coding (MDC) schemes with Distributed Video coding (DVC) principles. In this way, it is possible to obtain a better error resilience since the distortion drifting through the sequence is significantly mitigated by the DVC coding unit. The paper presents a multipledescription Distributed Video Coder (MDDVC) that codes the input video signal generating a set of "lossy" syndromes for each pixel block and creates different descriptions multiplexing primary and redundant video packets. Experimental results show that at high loss probabilities the proposed solution improves the results of the original MDC approach.
In this paper we address the problem of video transmission over unreliable networks. The proposed approach moves from the concept of multiple description coding (MDC) introducing some simple algorithms to obtain sub-s...
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ISBN:
(纸本)9789630626705
In this paper we address the problem of video transmission over unreliable networks. The proposed approach moves from the concept of multiple description coding (MDC) introducing some simple algorithms to obtain sub-streams introducing the concepts of either spatial, temporal, SNR adaptation. The proposed algorithms have been implemented as pre- post- processing of the basic H.264/SVC codec. Although in principle as many descriptions as desired can be generated, simulation results using only two description show good results both when all descriptions are received and when only one of the two is received. Analysis performed in case of either random or packet losses show the robustness of the algorithms.
A peer-to-peer (P2P) architecture for multipoint video conferencing using layered video coding at the end hosts is proposed. The system primarily targets end points with low bandwidth network connections and enables t...
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A peer-to-peer (P2P) architecture for multipoint video conferencing using layered video coding at the end hosts is proposed. The system primarily targets end points with low bandwidth network connections and enables them to create a multipoint video conference without any additional networking and computing resources beyond what is needed for a point-to-point conference. For P2P multipoint video conferencing applications, wide-area collaboration is significant for connecting participants from different parts around the globe to support collaborative work. In our system, peers collaborate for streaming video, and the motivation behind the use of layered video is to overcome the problem of denying video requests by peers and assure that each participant peer can view any other participant at any configuration. Layered video encoding techniques usable within this architecture are discussed. A protocol for operating the system has been developed, simulated and its performance has been analyzed. Furthermore, a multi-objective optimization approach has been developed to simultaneously minimize the number of base layer receivers and the delay experienced by the peers while maximizing the granted additional requests to support peers having multiple video input bandwidths. The use of the multi-objective optimization scheme is demonstrated through an example scenario and simulations. A prototype has also been implemented, and the system has been formally specified and verified. (C) 2010 Elsevier Ltd. All rights reserved.
In a peer-to-peer (P2P) network, peers not only receive services from the network, but also contribute their own resources to the network. The abundant resources brought by P2P networks have stimulated the wide deploy...
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In a peer-to-peer (P2P) network, peers not only receive services from the network, but also contribute their own resources to the network. The abundant resources brought by P2P networks have stimulated the wide deployment of resource-consuming multimedia streaming services over a P2P architecture. Allowing for the heterogeneity of peers in their upload and download bandwidth, most researches adopt the multiple description coding (MDC) technique to enable differentiated streaming services. However, due to the lack of a global view of description availability, they tend to cause the skewed distribution of descriptions and lead to the under-utilization of aggregated resources on P2P networks. In the paper, we propose a novel approach to balance the distribution of descriptions and available upload bandwidth in the P2P live streaming network. Based on the description distribution and available upload bandwidth, the proposed balancing scheme determines what descriptions a new peer should receive and their source peers such that better system scalability can be achieved. The simulation experiments indicate that our proposed balancing scheme can effectively reduce the server bandwidth consumption and rejection rate. Furthermore, abandoned peers can recover their lost descriptions mostly from the existing peers in the network instead of the server. Copyright (C) 2010 John Wiley & Sons, Ltd.
We propose a general N-channel MDC (multiple description coding) framework which can integrate the advantages of various low-dimensional MDC schemes. Given the operational rate-distortion functions of low-dimensional ...
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ISBN:
(纸本)9781424479948
We propose a general N-channel MDC (multiple description coding) framework which can integrate the advantages of various low-dimensional MDC schemes. Given the operational rate-distortion functions of low-dimensional codecs, we show how to optimize the proposed MDC framework. We prove that the optimization problem can be reduced to a combinatorial problem which in certain cases admits polynomial-time solutions. We then apply the proposed optimization algorithm to multipledescription image coding. Experiment results show the effectiveness of our approach.
Real-time multimedia streaming over MANETs is an active research field since this technology promises scalable and robust audio/video delivery without infrastructure. Even though this problem has several commune featu...
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Real-time multimedia streaming over MANETs is an active research field since this technology promises scalable and robust audio/video delivery without infrastructure. Even though this problem has several commune features with peer-to-peer routing, the additional sensible parameters of MANETs make wired solutions unfit to this case;therefore, we propose a content routing/delivery protocol inherently designed for the ad-hoc wireless case, exploiting the intrinsic broadcast property of the medium. We provided an implementation of this protocol and we tested it in several use-cases, observing how it assures availability, robustness and scalability.
Real-time video transcoding that is often needed for robust video broadcasting over heterogeneous networks is not supported in most existing devices. To address this problem, we propose a collaborative strategy that l...
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Real-time video transcoding that is often needed for robust video broadcasting over heterogeneous networks is not supported in most existing devices. To address this problem, we propose a collaborative strategy that leverages the peering architecture of peer-to-peer Internet protocol television networks and makes the computational resources of peers sharable. The video transcoding task is distributed among the peers and completed collaboratively. A prototype of the live video broadcasting system is evaluated over a 100-node testbed on the PlanetLab. The experimental results show that the proposed strategy works effectively even when the majority of the peers have limited computational resource and bandwidth.
Communication via the Internet spreads out nowadays. Multimedia data such as image or video are aimed to be sent over the Internet without error. multiple description coding (MDC) is an important coding/transmission m...
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We consider the problem of distributing video data from one sender to a population of interested clients. Deploying an overlay network with an application-layer multicast, we propose a scalable forward-error-correctio...
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We consider the problem of distributing video data from one sender to a population of interested clients. Deploying an overlay network with an application-layer multicast, we propose a scalable forward-error-correction-based, multiple-descriptioncoding packetization scheme to achieve optimal performance for each client.
In this paper, a novel multiple description coding technique is proposed, based on optimal Lagrangian rate allocation. The method assumes the coded data consists of independently coded blocks. Initially, all the block...
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In this paper, a novel multiple description coding technique is proposed, based on optimal Lagrangian rate allocation. The method assumes the coded data consists of independently coded blocks. Initially, all the blocks are coded at two different rates. Then blocks are split into two subsets with similar rate distortion characteristics;two balanced descriptions are generated by combining code blocks belonging to the two subsets encoded at opposite rates. A theoretical analysis of the approach is carried out, and the optimal rate distortion conditions are worked out. The method is successfully applied to the JPEG 2000 standard and simulation results show a noticeable performance improvement with respect to state-of-the art algorithms. The proposed technique enables easy tuning of the required coding redundancy. Moreover, the generated streams are fully compatible with Part I of the standard.
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