检索结果-内蒙古大学图书馆

An unequal error protection method for progressively transmitted 3-D models

IEEE TRANSACTIONS ON MULTIMEDIA 2005年第4期7卷 766-776页

作者： AlRegib, G Altunbasak, Y Rossignac, J Georgia Tech Ctr Signal & Image Proc Atlanta GA 30332 USA Georgia Inst Technol Sch Elect & Comp Engn Savannah GA 31407 USA Georgia Inst Technol Coll Comp Atlanta GA 30332 USA Georgia Inst Technol GVU Ctr Atlanta GA 30332 USA

In this paper, we present a packet-loss resilient system for the transmission of progressively compressed three-dimensional (3-D) models. It is based on a joint source and channel coding approach that trades off geometry precision for increased error resiliency to optimize the decoded model quality on the client side. We derive a theoretical framework for the overall system by which the channel packet loss behavior and the channel bandwidth can be directly related to the decoded model quality at the receiver. First, the 3-D model is progressively compressed into a base mesh and a number of refinement layers. Then, we assign optimal forward error correction code rates to protect these layers according to their importance to the decoded model quality. Experimental results show that with the proposed unequal error protection approach, the decoded model quality degrades more gracefully (compared to either no error protection or equal error protection methods) as the packet-loss rate increases.

关键词： joint source and channel coding multimedia networking packet loss resilient transmission unequal error protection (UEP) virtual reality over IP networks 3-D graphics streaming

来源：评论

学校读者我要写书评

暂无评论

Hermitian Symmetric DFT Codes: A New Class of Complex DFT Codes

引用

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2012年第5期60卷 2396-2407页

作者： Kumar, A. Anil Makur, Anamitra Nanyang Technol Univ Sch Elect & Elect Engn Singapore Singapore

We introduce a new class of real number codes derived from DFT matrix, Hermitian symmetric DFT (HSDFT) codes. We propose a new decoding algorithm based on coding-theoretic as well as subspace based approach. Decoding of HSDFT codes requires only real arithmetic operations and smaller dimension matrices compared to the decoding of the state-of-art real BCH DFT (RBDFT) class of codes. HSDFT codes will also be shown to have more burst error correction capacity. For a Gauss-Markov source, on a binary symmetric channel at lower to moderate bit error rates (BERs), HSDFT codes show better performance than RBDFT codes, and on a Gilbert-Elliot channel HSDFT codes consistently perform better than RBDFT codes.

关键词： DFT codes joint source and channel coding real number codes subspace algorithms

来源：评论

学校读者我要写书评

暂无评论

Realtime joint Speech coding and Transmission Algorithm for High Packet Loss Rate Wireless channels

引用

IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS 2008年第12期E91D卷 2892-2896页

作者： Peng, Tan Cui, Huijuan Miao, Wei Tsinghua Univ State Key Lab Microwave & Digital Commun Tsinghua Natl Lab Informat Sci & Technol Beijing 100084 Peoples R China Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China

In digital speech communication over noisy high packet loss rate wireless channels, improving the overall performance of the realtime speech coding and transmission system is of great importance. A novel joint speech coding and transmission algorithm is proposed by fully exploiting the correlation between speech coding, channel coding and the transmission process. The proposed algorithm requires no algorithm delay and less bandwidth expansion while greatly enhancing, the error correcting performance and the reconstructed speech quality compared with conventional algorithms. Simulations show that the residual error rate is reduced by 84.36% and the MOS (Mean Opinion Score) is improved over 38.86%.

关键词： speech coding joint source and channel coding coded transmission

来源：评论

学校读者我要写书评

暂无评论

MAP ESTIMATION OF MULTIPLE DESCRIPTION ENCODED VIDEO TRANSMITTED OVER NOISY channelS

MAP ESTIMATION OF MULTIPLE DESCRIPTION ENCODED VIDEO TRANSMI...

引用

16th IEEE International Conference on Image Processing

作者： Agostini, Marie Andree Antonini, Marc Kieffer, Michel Univ Nice Sophia Antipolis I3S Lab CNRS F-06903 Sophia Antipolis France Univ Paris Sud CNRS LSS Supelec F-91192 Gif Sur Yvette France

ISBN: (纸本)9781424456536

The problem of efficient video transmission over noisy channels involves high compression rates and robustness to channel errors. In the framework of multiple description coding (MDC), we focus on the direct estimation of the source from two noisy descriptions, without trying to estimate the single descriptions. The challenge is to reconstruct a central signal with distortion as small as possible using the knowledge of the two noisy descriptions. We propose in this paper a maximum a posteriori (MAP) estimator for the decoding of the central description, using the knowledge of the probability density function (pdf) of the different subband descriptions. The balanced MDC scheme used for application is a scan-based wavelet transform video coding scheme, and includes an efficient bit allocation procedure that dispatches the source video redundancy between the different descriptions, depending on the characteristics of the channel. Simulation results show a good robustness of the proposed decoding scheme against transmission errors, with an improvement of 2 dB in PSNR compared to a maximum likelihood (ML) technique.

关键词： joint source and channel coding multiple description video coding MAP estimation temporal wavelet transform bit allocation

来源：评论

学校读者我要写书评

暂无评论

A temporal error concealment technique for I-pictures in an MPEG-2 video-decoder

A temporal error concealment technique for I-pictures in an ...

引用

Visual Communications and Image Processing 1998 Conference

作者： Aign, S DLR German Aerosp Ctr Inst Commun Technol D-82234 Oberpfaffenhofen Germany

ISBN: (纸本)0819427497

For digital broadcasting of TV-signals over various transmission media like satellite, cable, and terrestrial channels, the MPEG-2 video source coding algorithm will be considered. Since the video-signal is very sensitive to channel disturbances due to variable length coding (VLC), a bit-error rate of;less than 10(-8) has to be guaranteed. Therefore, a powerful error protection scheme is applied in the European TV-Broadcasting Standards(1-3). However, in the case of bad reception conditions, e.g. deep fades or impulsive noise, remaining errors even in the highest protected video signal may still occur. With remaining errors in the video signal a good quality of service cannot be guaranteed. Therefore, some post-processing techniques such as error concealment and iterative decoding at the receiver side will be desirable(4). The aim of this article is to study different error concealment techniques for handling residual channel errors at the receiver side taking into account a real transmission media. For I-pictures, a motion compensated temporal error concealment algorithm is proposed where motion vectors are displaced along the motion direction.

关键词： error resilience error concealment MPEG-2 error detection joint source and channel coding

来源：评论

学校读者我要写书评

暂无评论

OPTIMAL MODE SELECTION AND channel coding FOR 3-D VIDEO STREAMING OVER THE INTERNET

OPTIMAL MODE SELECTION AND CHANNEL CODING FOR 3-D VIDEO STRE...

引用

IEEE International Conference on Multimedia and Expo (ICME)

作者： Gao, Pan Xiang, Wei Wang, Bing Nanjing Univ Aeronaut & Astronaut Coll Comp Sci & Technol Nanjing Jiangsu Peoples R China James Cook Univ Coll Sci & Engn Townsville Qld Australia Southwest Jiaotong Univ Sch Informat Sci & Technol Chengdu Sichuan Peoples R China

ISBN: (纸本)9781538605608

This paper addresses the problem of joint source and channel coding for 3-D video coding and transmission. Firstly, we formulate a packet-level joint texture and depth coding mode selection framework for error-resilient source coding using Lagrange multiplier. Then, we evolve to the more general formulation that jointly optimizes error-resilient source coding and channel coding for texture and depth with unequal error protection. Finally, based on the adjacent packet dependency, we derive a theoretic approach to efficiently find the optimal solution. The proposed algorithm explicitly considers the interaction between error-resilient source coding and channel coding tailored to 3-D video, and the different sensitivities of the view synthesis quality to texture distortion and depth distortion. Experimental results are presented for a wide range of packet loss rates in order to illustrate the benefit of the proposed 3-D video coding framework.

关键词： Mode selection channel coding joint source and channel coding 3-D video

来源：评论

学校读者我要写书评

暂无评论

Qos-guarantee error control for scalable image over wireless fading channel

Qos-guarantee error control for scalable image over wireless...

引用

Conference on Visual Communications and Image Processing 2002

作者： Wang, GJ Lin, XG Tsinghua Univ Dept Elect Engn Beijing 100084 Peoples R China

ISBN: (纸本)0819444111

With the emerging of the third generation (3G) wireless technology, digital media, like image and video, over wireless channel becomes more and more demanding. In this paper, the measure metrics for the wireless image is proposed and a Qos-guarantee error control is presented, combining UEP with Forward Error Correction (FEC) and Automatic Repeat reQuest (ARQ), aiming to high quality image transmission with short delay and little energy. Simulation results show that our scheme can achieve good reconstructed image with few retransmission times and small bit budget under different channel conditions, which can reduce the energy consumed in the network interface.

关键词： unequal error protection FEC ARQ scalable image communication JPEG2000 3G joint source and channel coding Reed-Solomon code bit allocation rate-distortion

来源：评论

学校读者我要写书评

暂无评论

Unequal error protection of the reference grid for robust transmission of MESHGRID-represented objects over error-prone channels

Unequal error protection of the reference grid for robust tr...

引用

Conference on Wavelet Applications in Industrial Processing IV

作者： Cernea, Dan C. Munteanu, Adrian Stoufs, Maryse Alecu, Alin Cornelis, Jan Schelkens, Peter Vrije Univ Brussels Dept Elect & Informat ETRO Interdisciplinary Inst Broadband Technol IBBT Pl Laan 2 B-1050 Brussels Belgium

ISBN: (纸本)9780819464811

The heterogeneous nature of modem communications stems from the need of transmitting digital information through various types of mediums to a large variety of end-user terminals. In this context, simultaneously providing a scalable source representation and resilience against transmission errors is of primary importance. MESHGRID, which is part of the MPEG-4 AFX standard, is a scalable 3D object representation method especially designed to address the heterogeneous nature of networks and clients in modem communication systems. A MESHGRID object comprises one or several surface layers attached to and located within a volumetric reference-grid. In this paper we focus on the error-resilience aspects of MESHGRID and propose a novel approach for scalable error-resilient coding of MESHGRID'S reference-grid. An unequal error protection approach is followed, to acquaint for the different effor-sensitivity levels characterizing the various resolution and quality layers produced by the reference-grid coder. The code rates to be employed for each layer are determined by solving a joint source and channel coding problem. The L-infinite distortion metric is employed instead of the classical L-2 norm, typically used in case of images and video. In this context, a novel fast algorithm for solving the optimization problem is proposed. The proposed approach allows for real-time implementations. The experimental results demonstrate the benefits brought by error resilient coding of the reference grid. We conclude that the proposed approach offers resilience against transmission errors while preserving all the scalability features and animation capabilities that characterize MESHGRID.

关键词： 3D graphics MESHGRID error resilient coding of surfaces joint source and channel coding unequal error protection scalable wavelet-based coding L-infinite coding

来源：评论

学校读者我要写书评

暂无评论

Double-binary turbo code for transmission of scalable video bitstream

Double-binary turbo code for transmission of scalable video ...

引用

48th International Symposium ELMAR-2006 on Multimedia Signal Processing and Communications

作者： Ramzan, N. Izquierdo, E. Queen Mary Univ London Mile End Rd London E1 4NS England

ISBN: (纸本)9789537044039

A novel low bit rate video transmission scheme is proposed for the communication of scalable video bitstream over wireless channel. The schema consists of motion compensated t + 2D wavelet decomposition scalable coder and double binary turbo code. Double binary codes were used for protection since they perform better than classical turbo coders in terms of better convergence for iterative decoding, a large minimum distance and computational cost. An efficient method to estimate the minimum distance of double binary turbo codes Is also proposed. The best packet length are evaluated by measuring the minimum distance of turbo ocode to adopt the scalable bitstream with unequal error protection. Simulation results show that the unequal error protection is quite efficient, even in very adverse conditions, and it clearly outperforms simple FEC techniques.

关键词： scalable video codec turbo code double binary turbo code minimum hamming distance joint source and channel coding

来源：评论

学校读者我要写书评

暂无评论

Corrupted video quality analysis of Error-Resilient 3-D SPIHT vs. MPEG-2

Corrupted video quality analysis of Error-Resilient 3-D SPIH...

引用

Conference on Visual Information Processing XII

作者： Han, KJ Suter, BW USAF Ctr Integrated Transmiss & Exploitat Res Lab Informat Directorate Rome NY 13441 USA

ISBN: (纸本)0819449687

A great deal of digital video quality measurement research has been performed to quantify human visual perception with compressed video clips. Since transmitted video quality is heavily dependent on the bit-rate, error rate and dropped packet rate, a new measurement paradigm is required to analyze the corrupted video. Fast eigen-based video quality metric (VQM) and visualization techniques have been developed to measure and analyze the corrupted video qualities objectively. 3-D SPIHT and MPEG-2 with for-ward error correction (FEC) had been tested over a Video CODEC RF Test-bed. The experimental results indicate that the proposed scheme is useful for a low complexity VQM.

关键词： video quality metric (VQM) video communication error-resilient video coding 3-D SPIHT MPEG-2 synchronization variable length codes fixed-length codes high compression joint source and channel coding burst errors random errors forward error correction (FEC) principal component analysis

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：