检索结果-内蒙古大学图书馆

Energy-Efficient Video Multicast in 4G Wireless Systems

IEEE TRANSACTIONS ON MOBILE COMPUTING 2012年第10期11卷 1508-1522页

作者： Yu, Ya-Ju Hsiu, Pi-Cheng Pang, Ai-Chun Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei 106 Taiwan Acad Sinica Res Ctr Informat Technol Innovat CITI Taipei 115 Taiwan Acad Sinica IIS Taipei 115 Taiwan Natl Taiwan Univ Grad Inst Networking & Multimedia Taipei 106 Taiwan Natl Taiwan Univ Dept Comp Sci & Informat Engn Taipei 106 Taiwan

Layer-based video coding, together with adaptive modulation and coding, is a promising technique for providing real-time video multicast services on heterogeneous mobile devices. With the rapid growth of data communications for emerging applications, reducing the energy consumption of mobile devices is a major challenge. This paper addresses the problem of resource allocation for video multicast in fourth-generation wireless systems, with the objective of minimizing the total energy consumption for data reception. First, we consider the problem when scalable video coding is applied. We prove that the problem is NP-hard and propose a 2-approximation algorithm to solve it. Then, we investigate the problem under multiple description coding, and show that it is also NP-hard and cannot be approximated in polynomial time with a ratio better than 2, unless P = NP. To solve this case, we develop a pseudopolynomial time 2-approximation algorithm. The results of simulations conducted to compare the proposed algorithms with a brute-force optimal algorithm and a conventional approach are very encouraging.

关键词： Energy efficiency video multicast scalable video coding multiple description coding adaptive modulation and coding 4G wireless systems

来源：评论

学校读者我要写书评

暂无评论

On joint routing and server selection for MD video streaming in ad hoc networks

引用

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2007年第1期6卷 338-347页

作者： Mao, Shiwen Cheng, Xiaolin Hou, Y. Thomas Sherali, Hanif D. Reed, Jeffrey H. Auburn Univ Dept Elect & Comp Engn Auburn AL 36849 USA Virginia Tech Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA Univ Calif Davis Dept Comp Sci Davis CA 95616 USA Virginia Tech Grado Dept Ind & Syst Engn Blacksburg VA 24061 USA

For media streaming in ad hoc networks, service replication has been demonstrated to be a quite effective countermeasure to streaming interruptions caused by fragile-paths and dynamic topology. In this paper, we study the problem of joint routing and server selection for double description (DD) video streaming in ad hoc networks. We formulate the task as a combinatorial optimization problem and present tight lower and upper bounds for the achievable distortion. The upper bound provides a feasible solution to the formulated problem. Our extensive numerical results show that the bounds are very close to each other for all the cases studied, indicating the near-global optimality of the derived upper bounding solution. Moreover, we observe significant gains in video quality achieved by the proposed approach over existing server selection schemes. This justifies the importance of jointly considering routing and server selection for optimal MD video streaming.

关键词： ad hoc network multiple description coding routing video streaming server diversity

来源：评论

学校读者我要写书评

暂无评论

A fine-grained balancing scheme for improved scalability in P2P streaming

引用

MULTIMEDIA TOOLS AND APPLICATIONS 2010年第1期46卷 71-90页

作者： Lin, Chow-Sing Syu, Wei-Ting Natl Univ Tainan Dept Comp Sci & Informat Engn Tainan 700 Taiwan So Taiwan Univ Dept Informat Management Yung Kang 710 Tainan Shien Taiwan

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.

关键词： Peer-to-peer Streaming multiple description coding Load balancing Scalability

来源：评论

学校读者我要写书评

暂无评论

Optimal correlating transform for erasure channels

引用

IEEE SIGNAL PROCESSING LETTERS 2005年第10期12卷 677-680页

作者： Romano, G Rossi, PS Palmieri, F Univ Naples 2 Dipartimento Ingn Informaz I-81031 Aversa CE Italy Univ Naples Federico II Dipartimento Informat & Sistemist I-80125 Naples Italy

In this letter, we derive a gradient-based algorithm for computing the optimal transform when coefficients are transmitted over an erasure channel whose statistics are known. The discrete transform introduces correlation among the coefficients with consequent performance improvement against losses. Simulations show appreciable improvements over standard schemes and also good robustness when loss probabilities are only roughly estimated.

关键词： erasure channel multiple description coding transform coding

来源：评论

学校读者我要写书评

暂无评论

Lattice-Based Robust Distributed Source coding for Three Correlated Sources

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2020年第7期68卷 4089-4103页

作者： Dumitrescu, Sorina Elzouki, Dania Chen, Jun McMaster Univ Dept Elect & Comp Engn Hamilton ON L8S 4K1 Canada

The problem of robust distributed source coding for three correlated sources is studied in this work. A lattice-based scheme is proposed and the analysis of its performance is provided in the high resolution regime. Special attention is paid to the degenerate case where the three sources are Gaussian and identical. In this case, our scheme is shown to achieve within an asymptotic gap of 0.069 bits in terms of rate per description from the information-theoretic limit of quadratic symmetric Gaussian multiple description coding with central and individual decoders, when the side distortion and the ratio between the central and side distortions both approach 0.

关键词： Lattices Decoding Robustness Source coding Distortion Indexes Correlated sources distributed source coding lattice quantization asymptotic performance analysis high resolution multiple description coding

来源：评论

学校读者我要写书评

暂无评论

Coarse scale cost-utility approach for efficient unequal loss protection

引用

SIGNAL PROCESSING-IMAGE COMMUNICATION 2002年第8期17卷 587-596页

作者： Chen, YS Wang, GP Dong, SH Peking Univ HCI & Multimedia Lab Dept Comp Sci Beijing 100871 Peoples R China

The framework of unequal loss protection (ULP) is an attractive method for the protection of the embedded image or video data source generated by a scalable coding scheme in the environment of packet switched networks. In this paper, an efficient preprocessing algorithm is presented based on the idea of the coarse scale cost-utility (CSCU) working curve. The experimental results show that the CSCU method significantly improves the efficiency of the ULP assignment framework with substantial memory and computation savings. We believe that the idea of coarse scale operation can also be successfully used in many other applications. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： scalable coding unequal loss protection forward error correcting multiple description coding

来源：评论

学校读者我要写书评

暂无评论

multiple description video multicast in wireless ad hoc networks

引用

MOBILE NETWORKS & APPLICATIONS 2006年第1期11卷 63-73页

作者： Mao, SW Cheng, XL Hou, YT Sherali, HD Virginia Tech Bradley Dept Elect & Comp Engn Blacksburg VA 24061 USA Virginia Tech Grad Dept Ind & Syst Engn Blacksburg VA 24061 USA

multiple description (MD) coding is a new video coding technique that is uniquely suitable for video transport over wireless ad hoc networks. In this paper, we consider the problem of how to support video multicast with MD video in ad hoc networks. We follow an application-centric, cross-layer routing approach with the objective of minimizing the overall video distortion. We propose an MD video multicast scheme where multiple source trees are used. Furthermore, each video description is coded into multiple layers in order to cope with diversity in wireless link bandwidths. Based on this multicast model, we formulate the cross-layer multicast routing as a combinatorial optimization problem and propose an efficient Genetic Algorithm (GA)-based metaheuristic solution procedure. Performance comparison with existing approaches show significant gains for a wide range of network operating conditions.

关键词： cross-layer design genetic algorithms multiple description coding routing video multicast wireless ad hoc networks

来源：评论

学校读者我要写书评

暂无评论

Layered coded vs. multiple description coded video over error-prone networks

引用

SIGNAL PROCESSING-IMAGE COMMUNICATION 2003年第5期18卷 337-356页

作者： Lee, YC Kim, J Altunbasak, Y Mersereau, RM Georgia Inst Technol Sch Elect & Comp Engn Atlanta GA 30332 USA

Layered (LC) and multiple description coding (MDC) have been proposed as source coding techniques that are robust to channel errors for video transmission. LC and MDC have similar characteristics: they both generate multiple sub-bitstreams, and it is permissible to drop some portion of the data from the sub-bitstreams during transmission for both methods. However, they are different in the sense that the sub-bitstreams for LC have different levels of importance while all sub-bitstreams for MDC are equally important. Since these two encoding techniques have similar properties, some performance comparisons between LC and MDC have recently been reported. However, these studies are still not conclusive because several scenarios have not been carefully considered. Furthermore, they have been performed in different environments. In this paper, we further investigate the error-resilience capabilities of these two encoding techniques through extensive experimentation. Although some of our conclusions agree with those in the literature, we believe that this paper provides the most comprehensive performance comparison yet between LC and MDC. (C) 2003 Elsevier Science B.V. All rights reserved.

关键词： layered coding multiple description coding error-resilient video communications MPEG video

来源：评论

学校读者我要写书评

暂无评论

Grassmannian frames with applications to coding and communication

引用

APPLIED AND COMPUTATIONAL HARMONIC ANALYSIS 2003年第3期14卷 257-275页

作者： Strohmer, T Heath, RW Univ Calif Davis Dept Math Davis CA 95616 USA Univ Texas Dept Elect & Comp Engn Austin TX 78727 USA

For a given class F of unit norm frames of fixed redundancy we define a Grassmannian frame as one that minimizes the maximal correlation \\ among all frames {f(k)}(kis an element ofI) is an element of F. We first analyze finite-dimensional Grassmannian frames. Using links to packings in Grassmannian spaces and antipodal spherical codes we derive bounds on the minimal achievable correlation for Grassmannian frames. These bounds yield a simple condition under which Grassmannian frames coincide with unit norm tight frames. We exploit connections to graph theory, equiangular line sets, and coding theory in order to derive explicit constructions of Grassmannian frames. Our findings extend recent results on unit norm tight frames. We then introduce infinite-dimensional Grassmannian frames and analyze their connection to unit norm tight frames for frames which are generated by group-like unitary systems. We derive an example of a Grassmannian Gabor frame by using connections to sphere packing theory. Finally we discuss the application of Grassmannian frames to wireless communication and to multiple description coding. (C) 2003 Elsevier Science (USA). All rights reserved.

关键词： frame Grassmannian spaces spherical codes Gabor frame multiple description coding unit norm tight frame conference matrix equiangular line sets unitary system

来源：评论

学校读者我要写书评

暂无评论

A cross-layer diversity technique for multicarrier OFDM multimedia networks

引用

IEEE TRANSACTIONS ON IMAGE PROCESSING 2006年第4期15卷 833-847页

作者： Chan, YS Cosman, PC Milstein, LB Univ Calif San Diego Dept Elect & Comp Engn La Jolla CA 92093 USA

Diversity can be used to combat multipath fading and improve the performance of wireless multimedia communication systems. In this work, by considering transmission of an embedded bitstream over an orthogonal frequency division multiplexing (OFDM) system in a slowly varying Rayleigh faded environment, we develop a cross-layer diversity technique which takes advantage of both multiple description coding and frequency diversity techniques. More specifically, assuming a frequency-selective channel, we study the packet loss behavior of an OFDM system and construct multiple independent descriptions using an FEC-based strategy. We provide some analysis of this cross-layer approach and demonstrate its superior performance using the set partitioning in hierarchical trees image coder.

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

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：