In peer-to-peer video-on-demand streaming networks, the alleviation of server load depends on reciprocal stream sharing among peers. In general, on-demand video services enable clients to watch videos from beginning t...
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In peer-to-peer video-on-demand streaming networks, the alleviation of server load depends on reciprocal stream sharing among peers. In general, on-demand video services enable clients to watch videos from beginning to the end in a pipeline fashion. As long as a client still caches the initial part of the video, it can provide on-demand service to the subsequent clients without intervention of a server. Therefore, the key challenge is how to maximize the availability of a video for stream relay by keeping the initial part of a video in a peer's buffer as long as possible. In addition, to address the issues of delivering data on lossy network and providing scalable video quality of services for clients, the adoption of multiple description coding has been proven as a feasible resolution by much research work. In this paper, we propose a novel caching scheme for P2P on-demand streaming called Balanced Dynamic Buffering with multiple description coding. The proposed balanced dynamic buffering gradually reduces the number of buffered descriptions once the buffer of a peer gets full. In addition, peers are grouped based on the number of descriptions cached in their buffer. The intra-group balancing and inter-group balancing are applied for well distributing descriptions and balancing their forwarding bandwidth on peer-to-peer on-demand streaming networks. In the paper, we also propose the failure recovery for the balanced dynamic buffering scheme. Simulation results showed that the balanced dynamic buffering significantly outperformed other dynamic buffering schemes and the CoopNet in server bandwidth utilization, and a longer buffer in a peer did favor the failure recovery on peer-to-peer on-demand streaming networks.
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 GPN...
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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-descriptioncoding 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.
In this paper, a novel H.264 multipledescription technique is proposed. The coding approach is based on the redundant slice representation option, defined in the H.264 standard. In presence of losses, the redundant r...
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In this paper, a novel H.264 multipledescription technique is proposed. The coding approach is based on the redundant slice representation option, defined in the H.264 standard. In presence of losses, the redundant representation can be used to replace missing portions of the compressed bit stream, thus yielding a certain degree of error resilience. This paper addresses the creation of two balanced descriptions based on the concept of redundant slices, while keeping full compatibility with the H.264 standard syntax and decoding behavior in case of single description reception. When two descriptions are available still a standard H.264 decoder can be used, given a simple preprocessing of the received compressed bit streams. An analytical setup is employed in order to optimally select the amount of redundancy to be inserted in each frame, taking into account both the transmission condition and the video decoder error propagation. Experimental results demonstrate that the proposed technique favorably compares with other H.264 multipledescription approaches.
In this correspondence, we consider the multiuser successive refinement (MSR) problem, where the users are connected to a central server via links with different noiseless capacities, and each user wishes to reconstru...
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In this correspondence, we consider the multiuser successive refinement (MSR) problem, where the users are connected to a central server via links with different noiseless capacities, and each user wishes to reconstruct in a successive-refinement fashion. An achievable region is given for the two-user two-layer case and it provides the complete rate-distortion region for the Gaussian source under the MSE distortion measure. The key observation is that this problem includes the multipledescription (MD) problem (with two descriptions) as a subsystem, and the techniques useful in the MD problem can be extended to this case. It is shown that the coding scheme based on the universality of random binning is suboptimal, because multiple Gaussian side informations only at the decoders do incur performance loss, in contrast to the case of single side information at the decoder. It is further shown that unlike the single user case, when there are multiple users, the loss of performance by a multistage coding approach can be unbounded for the Gaussian source. The result suggests that in such a setting, the benefit of using successive refinement is not likely to justify the accompanying performance loss. The MSR problem is also related to the source coding problem where each decoder has its individual side information, while the encoder has the complete set of the side informations. The MSR problem further includes several variations of the MD problem, for which the specialization of the general result is investigated and the implication is discussed.
In P2P systems, because the buffer space of each peer is limited, most of P2P systems employ the cache-and-relay schemes that require each peer to cache the most recent video stream it receives. As long as the initial...
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ISBN:
(纸本)9781479924189
In P2P systems, because the buffer space of each peer is limited, most of P2P systems employ the cache-and-relay schemes that require each peer to cache the most recent video stream it receives. As long as the initial part of the video stream remains in its buffer, the peer can then relay the cached stream to late-arriving peers in a pipelining fashion and then the loading of a server is reduced. In our previous research work, we proposed a novel caching scheme for peer-to-peer on-demand streaming, called Dynamic Buffering, which relies on the feature of multiple description coding to gradually reduce the number of cached descriptions in a peer once the buffer is full. In this paper we discuss service availability of a peer with dynamic buffering for various numbers of kinds of forwarded descriptions, and provide detailed analyses on how the number of kinds of forwarded descriptions affects average service availability of a peer. In addition, the mathematical formulas of the reduction of average service availability for various numbers of kinds of forwarded descriptions is derived. Our experiment results showed that the reduction of average service availability is only related to the number of kinds of forwarded descriptions.
We propose an algorithm that improves the performance of rate-distortion-based multiple description coding (RD-MDC). The gain is particularly significant in the high redundancy region, where RD-MDC suffers a major per...
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We propose an algorithm that improves the performance of rate-distortion-based multiple description coding (RD-MDC). The gain is particularly significant in the high redundancy region, where RD-MDC suffers a major performance penalty with respect to MDC bounds. The improvement is obtained with negligible additional computational cost, by exploiting the coarse information also at the central decoder. The proposed method can be generalized to all MDC schemes that use scalar quantization, without modifying the quantizer structure. This feature guarantees the generation of descriptions that can be decoded without any modification of the decoder.
The compressed sensing paradigm allows to efficiently represent sparse signals by means of their linear measurements. However, the problem of transmitting these measurements to a receiver over a channel potentially pr...
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ISBN:
(纸本)9781479903566
The compressed sensing paradigm allows to efficiently represent sparse signals by means of their linear measurements. However, the problem of transmitting these measurements to a receiver over a channel potentially prone to packet losses has received little attention so far. In this paper, we propose novel methods to generate multipledescriptions from compressed sensing measurements to increase the robustness over unreliable channels. In particular, we exploit the democracy property of compressive measurements to generate descriptions in a simple manner by partitioning the measurement vector and properly allocating bit-rate, outperforming classical methods like the multipledescription scalar quantizer. In addition, we propose a modified version of the Basis Pursuit Denoising recovery procedure that is specifically tailored to the proposed methods. Experimental results show significant performance gains with respect to existing methods.
Several studies indicate that video contents will be the vast majority of Internet traffic in the near future. To facilitate the distribution of video contents, we have to overcome the issue of interoperability betwee...
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ISBN:
(纸本)9781479900749
Several studies indicate that video contents will be the vast majority of Internet traffic in the near future. To facilitate the distribution of video contents, we have to overcome the issue of interoperability between various servers and devices. MPEG-DASH standard is developed to provide standardized manifest format, content format and streaming protocol for adaptive streaming, thereby increasing interoperability. However, MPEG-DASH contents are delivered by HTTP without supporting data multicast. Since delivering video contents over multicast channels is necessary or useful for some applications, the authors survey the studies of delivering MPEG-DASH contents over multicast channels. It is found that few studies discuss the detailed construction of such a mechanism. This paper proposes three methods enabling the delivery of MPEG-DASH contents over multicast are proposed. And also evaluates the performance of the proposed methods over real WiFi networks. The result shows that each method has its own advantages and therefore suitable for different applications.
This paper focuses on the problem of L-channel quadratic Gaussian multipledescription (MD) coding. We recently introduced a new encoding scheme in [1] for general L-channel MD problem, based on a technique called ...
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ISBN:
(纸本)9781479904464
This paper focuses on the problem of L-channel quadratic Gaussian multipledescription (MD) coding. We recently introduced a new encoding scheme in [1] for general L-channel MD problem, based on a technique called 'Combinatorial Message Sharing' (CMS), where every subset of the descriptions shares a distinct common message. The new achievable region subsumes the most well known region for the general problem, due to Venkataramani, Kramer and Goyal (VKG) [2]. Moreover, we showed in [3] that the new scheme provides a strict improvement of the achievable region for any source and distortion measures for which some 2-description subset is such that the Zhang and Berger (ZB) scheme achieves points outside the El-Gamal and Cover (EC) region. In this paper, we show a more surprising result: CMS outperforms VKG for a general class of sources and distortion measures, which includes scenarios where for all 2-description subsets, the ZB and EC regions coincide. In particular, we show that CMS strictly extends VKG region, for the L-channel quadratic Gaussian MD problem for all L >= 3, despite the fact that the EC region is complete for the corresponding 2-descriptions problem. Using the encoding principles derived, we show that the CMS scheme achieves the complete rate-distortion region for several asymmetric cross-sections of the L-channel quadratic Gaussian MD problem, which have not been considered earlier.
This paper presents a new low complexity multiple description coding (MDC) method that can generate any number of descriptions. For correlated sources, a special DPCM encoder is used in each description, such that it ...
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ISBN:
(纸本)9781424417650
This paper presents a new low complexity multiple description coding (MDC) method that can generate any number of descriptions. For correlated sources, a special DPCM encoder is used in each description, such that it carries higher rate information of a subset of the samples and lower rate information of the rest. The lower rate codings in different descriptions are designed to be mutually refinable using staggered scalar quantizers. The closed-form expression of the expected distortion is derived when an arbitrary subset of the descriptions are received. Experimental results on natural images using lapped transform show that the proposed method is competent with the state-of-the-art multipledescription image coders.
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