Supporting multimedia applications over wireless networks has become a very active research topic recently because video applications are forecast to receive high demand in future wireless networks, such as ad hoc net...
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Supporting multimedia applications over wireless networks has become a very active research topic recently because video applications are forecast to receive high demand in future wireless networks, such as ad hoc networks. However, enabling video transmission over wireless ad hoc networks is more challenging than over other wireless networks due to node mobility, interference, and the absence of a supporting in frastructure. This paper addresses the problem of video transmission over ad hoc networks. We propose to combine multiple description coding (MDC) with multiple source transport (Multipoint-to-Point transfer: MP2P) in order to maintain smooth video streaming over wireless ad hoc networks. In this paper, we describe a comprehensive simulation and test bed experiment designed to show the effect of the proposed MP2P video transfer with MDC for two description cases of video streaming over wireless ad hoc networks. The results Show that the proposed mechanism successfully improves video transfer performance in terms of video packet reachability and throughput. (c) 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(4): 43-50, 2010;Published online in Wiley InterScience (***). DOI 10.1002/eej.20999
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.
In this paper, we propose a deep semantic segmentation-based multiple description coding (DSSMDC). In the proposed scheme, the input image is divided into two different subsets and getting two descriptions, which is n...
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In this paper, we propose a deep semantic segmentation-based multiple description coding (DSSMDC). In the proposed scheme, the input image is divided into two different subsets and getting two descriptions, which is named multipledescription pre-processing (MDP). Then, two descriptions are encoded and decoded respectively by utilizing the deep semantic segmentation codec, in which the semantic segmentation label is as side information for improving image reconstruction quality. We can get one side reconstruction, when only one description is received at the decoder. If both descriptions are received at the decoder, we can get the central reconstruction. Experimental results show that the proposed scheme achieves better performance than other existing compression methods.
This work presents an LDGM-based practical successive coding scheme for the multipledescription (MD) problem for finite alphabet sources. The scheme, which targets the Zhang-Berger (ZB) rate-distortion region, is sho...
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This work presents an LDGM-based practical successive coding scheme for the multipledescription (MD) problem for finite alphabet sources. The scheme, which targets the Zhang-Berger (ZB) rate-distortion region, is shown to be asymptotically optimal with joint typicality encoding, while as a practical encoding solution a message passing algorithm is adopted. We further discuss in more detail the application of the coding scheme in three cases of the MD problem with the Hamming distortion measure: 1) no excess sum-rate for binary sources, 2) successive refinement, and 3) no excess marginal rate for the uniform binary source. In the no excess sum-rate case some progress is made in the characterization of fundamental limits by deriving the analytical expression of the distortion region for general binary sources, and of the auxiliary variables needed to achieve its boundary. The exact expression of the Zhang-Berger upper bound to the central distortion is also provided for the case of no excess marginal rate for the uniform binary source. The proposed LDGM-based coding scheme is tested in practice for all three aforementioned cases. The experimental results show very good performance, demonstrating its ability to approach the theoretical rate-distortion limits or the available upper bounds.
Owing to the wide deployment of broadband networks, information can now be rapidly disseminated all over the world. Only the content of static texts and pictures has not yet met users' demands. Along with the rapi...
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Owing to the wide deployment of broadband networks, information can now be rapidly disseminated all over the world. Only the content of static texts and pictures has not yet met users' demands. Along with the rapid advance of computer-related technologies, how to efficiently provide multimedia content for a large number of heterogeneous users on the Internet, especially videos, has become a noticeable issue. In this paper, we discuss the adaptation of multiple description coding (MDC) for the loopback buffering mechanism to address the issue of peer heterogeneity on content distribution network peer to peer (CDN-P2P) video-on-demand systems. Three description selection policies, Ordered, Round-Robin, and Open-Loop-First (OLF), are studied. In addition, we propose the intra-description recovery and inter-description recovery to deal with failed peers. The simulation results show that the OLF with loopback-MDC can significantly reduce the amount of uploading bandwidth of a proxy on CDN-P2P video-on-demand systems, and the inter-description recovery, sewing, can further effectively recover missing blocks and restore the continuity of a breaking sharing loop among peers. Copyright (C) 2009 John Wiley & Sons, Ltd.
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.
A novel multiple description coding framework, called structure unanimity multiple description coding, is proposed in this paper. Each wavelet coefficient is first decomposed into an odd position coefficient made from...
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A novel multiple description coding framework, called structure unanimity multiple description coding, is proposed in this paper. Each wavelet coefficient is first decomposed into an odd position coefficient made from the bits in the odd positions and an even position coefficient made from the bits in the even positions. These two types of coefficients form the odd image and the even image, respectively, which are next encoded, and then transmitted using two different channels. Since the two images share the same hierarchical tree structure, only coefficient values in the redundancy parts need to be coded, resulting in improved coding efficiency. To meet the requirements of the packet switching network, these two images are rearranged in tree blocks, and the tree blocks in the even image and odd image are grouped to form the row and column packets, respectively. These packets are next separately dispatched through diverse channels. Since the row and the column packets have limited intersections, even with simultaneous loss of row and column packets, the proposed system exhibits good error resilient ability. Experimental results have verified the improved performance of the proposed algorithm. (C) 2007 Published by Elsevier B.V.
Digital watermarking is a useful solution for digital rights management systems, and it has been a popular research topic in the last decade. Most watermarking related literature focuses on how to resist deliberate at...
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Digital watermarking is a useful solution for digital rights management systems, and it has been a popular research topic in the last decade. Most watermarking related literature focuses on how to resist deliberate attacks by applying benchmarks to watermarked media that assess the effectiveness of the watermarking algorithm. Only a few papers have concentrated on the error-resilient transmission of watermarked media. In this paper, we propose an innovative algorithm for vector quantization (VQ) based image watermarking, which is suitable for error-resilient transmission over noisy channels. By incorporating watermarking with multiple description coding (MDC), the scheme we propose to embed multiple watermarks can effectively overcome channel impairments while retaining the capability for copyright and ownership protection. In addition, we employ an optimization technique, called tabu search, to optimize both the watermarked image quality and the robustness of the extracted watermarks. We have obtained promising simulation results that demonstrate the utility and practicality of our algorithm. (C) 2011 Elsevier Inc. All rights reserved.
We clarify the relationship among several existing achievable multipledescription rate-distortion regions by investigating the role of refinement layer in multiple description coding. Specifically, we show that the r...
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We clarify the relationship among several existing achievable multipledescription rate-distortion regions by investigating the role of refinement layer in multiple description coding. Specifically, we show that the refinement layer in the El Gamal-Cover (EGC) scheme and the Venkataramani-Kramer-Goyal (VKG) scheme can be removed;as a consequence, the EGC region is equivalent to the EGC* region (an antecedent version of the EGC region) while the VKG region (when specialized to the 2-description case) is equivalent to the Zhang-Berger (ZB) region. Moreover, we prove that for multiple description coding with individual and hierarchical distortion constraints, the number of layers in the VKG scheme can be significantly reduced when only certain weighted sum rates are concerned. The role of refinement layer in scalable coding (a special case of multiple description coding) is also studied.
The rate region of Gaussian multiple description coding with individual and central distortion constraints is completely characterized. Specifically, a lower bound and an upper bound are derived for each supporting hy...
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The rate region of Gaussian multiple description coding with individual and central distortion constraints is completely characterized. Specifically, a lower bound and an upper bound are derived for each supporting hyperplane of the rate region, where the lower bound is associated with a max-min game while the upper bound is associated with a min-max game;furthermore, it is shown that these two bounds coincide due to the existence of a saddle point.
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