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Macroblock Importance Estimation Based Resynchronization Approach
基于宏块重要性测度的重同步方法

QIU Jin-bo,FENG Bin,YU Li,ZHU Guang-xi,
邱锦波
,冯镔,喻莉,朱光喜

计算机科学 , 2010,
Abstract: Resynchronization is an important error resilient approach for video transmission.The video transmission distortion was analyzed and a new macroblock importance estimation based resynchronization approach was proposed.Through the definition of macroblock importance estimation,the approach utilized the macroblock importance combining with the bit stream length to packet compressed video with the same importance.The proposed approach is compared with number of macroblock based method and bit stream length bas...
A Global Rate-Distortion Optimized Approach to H.26L Low Bit Rate Robust Video over the Internet
提高H.26L压缩视频抗误码性能的全局率失真优化方法

Yang Hua,Yu Song-yu,Yang Song-an,
杨华
,余松煜,杨松岸

电子与信息学报 , 2004,
Abstract: A new Global Rate Distortion(GRD) optimal macroblock coding mode decision scheme is introduced for the newly H.26L video compression standard. Based on the Internet packet loss model of Bernoulli and Gilbert, this R-D mode decision approach can result in higher error robust than classical method. Furthermore, our experimental results also demonstrate its superior adaptive error resilient ability and practicability.
End-to-End Rate-Distortion Optimized MD Mode Selection for Multiple Description Video Coding  [cached]
Heng Brian A,Apostolopoulos John G,Lim Jae S
EURASIP Journal on Advances in Signal Processing , 2006,
Abstract: Multiple description (MD) video coding can be used to reduce the detrimental effects caused by transmission over lossy packet networks. A number of approaches have been proposed for MD coding, where each provides a different tradeoff between compression efficiency and error resilience. How effectively each method achieves this tradeoff depends on the network conditions as well as on the characteristics of the video itself. This paper proposes an adaptive MD coding approach which adapts to these conditions through the use of adaptive MD mode selection. The encoder in this system is able to accurately estimate the expected end-to-end distortion, accounting for both compression and packet loss-induced distortions, as well as for the bursty nature of channel losses and the effective use of multiple transmission paths. With this model of the expected end-to-end distortion, the encoder selects between MD coding modes in a rate-distortion (R-D) optimized manner to most effectively tradeoff compression efficiency for error resilience. We show how this approach adapts to both the local characteristics of the video and network conditions and demonstrates the resulting gains in performance using an H.264-based adaptive MD video coder.
Joint redundant motion vector and intra macroblock refreshment for video transmission  [cached]
Xiao Jimin,Tillo Tammam,Lin Chunyu,Zhao Yao
EURASIP Journal on Image and Video Processing , 2011,
Abstract: This paper proposes a scheme for error-resilient transmission of videos which jointly uses intra macroblock refreshment and redundant motion vector. The selection of using intra refreshment or redundant motion vector is determined by the rate-distortion optimization procedure. The end-to-end distortion is used for the rate-distortion optimization, which can be easily calculated with the recursive optimal per-pixel estimate (ROPE) method. Simulation results show that the proposed method outperforms both the intra refreshment approach and redundant motion vector approach significantly, when the two approaches are deployed separately. Specifically, for the Foreman sequence, the average PSNR of the proposed approach can be 1.12 dB higher than that of the intra refreshment approach and 5 dB higher than that of the redundant motion vector approach.
Rate-Distortion Optimization for Stereoscopic Video Streaming with Unequal Error Protection  [cached]
A. Serdar Tan,Anil Aksay,Gozde Bozdagi Akar,Erdal Arikan
EURASIP Journal on Advances in Signal Processing , 2008, DOI: 10.1155/2009/632545
Abstract: We consider an error-resilient stereoscopic streaming system that uses an H.264-based multiview video codec and a rateless Raptor code for recovery from packet losses. One aim of the present work is to suggest a heuristic methodology for modeling the end-to-end rate-distortion (RD) characteristic of such a system. Another aim is to show how to make use of such a model to optimally select the parameters of the video codec and the Raptor code to minimize the overall distortion. Specifically, the proposed system models the RD curve of video encoder and performance of channel codec to jointly derive the optimal encoder bit rates and unequal error protection (UEP) rates specific to the layered stereoscopic video streaming. We define analytical RD curve modeling for each layer that includes the interdependency of these layers. A heuristic analytical model of the performance of Raptor codes is also defined. Furthermore, the distortion on the stereoscopic video quality caused by packet losses is estimated. Finally, analytical models and estimated single-packet loss distortions are used to minimize the end-to-end distortion and to obtain optimal encoder bit rates and UEP rates. The simulation results clearly demonstrate the significant quality gain against the nonoptimized schemes.
Fast Macroblock Mode Selection Algorithm for Multiview Video Coding  [cached]
Zongju Peng,Gangyi Jiang,Mei Yu,Qionghai Dai
EURASIP Journal on Image and Video Processing , 2009, DOI: 10.1155/2008/393727
Abstract: Multiview video coding (MVC) plays an important role in three-dimensional video applications. Joint Video Team developed a joint multiview video model (JMVM) in which full-search algorithm is employed in macroblock mode selection to provide the best rate distortion performance for MVC. However, it results in a considerable increase in encoding complexity. We propose a hybrid fast macroblock mode selection algorithm after analyzing the full-search algorithm of JMVM. For nonanchor frames of the base view, the proposed algorithm halfway stops the macroblock mode search process by designing three dynamic thresholds. When nonanchor frames of the other views are being encoded, the macroblock modes can be predicted from the frames of the neighboring views due to the strong correlations of the macroblock modes. Experimental results show that the proposed hybrid fast macroblock mode selection algorithm promotes the encoding speed by 2.37 ¢ € ‰ ¢ ¢ € ‰9.97 times without noticeable quality degradation compared with the JMVM.
Fast Macroblock Mode Selection Algorithm for Multiview Video Coding  [cached]
Peng Zongju,Jiang Gangyi,Yu Mei,Dai Qionghai
EURASIP Journal on Image and Video Processing , 2008,
Abstract: Multiview video coding (MVC) plays an important role in three-dimensional video applications. Joint Video Team developed a joint multiview video model (JMVM) in which full-search algorithm is employed in macroblock mode selection to provide the best rate distortion performance for MVC. However, it results in a considerable increase in encoding complexity. We propose a hybrid fast macroblock mode selection algorithm after analyzing the full-search algorithm of JMVM. For nonanchor frames of the base view, the proposed algorithm halfway stops the macroblock mode search process by designing three dynamic thresholds. When nonanchor frames of the other views are being encoded, the macroblock modes can be predicted from the frames of the neighboring views due to the strong correlations of the macroblock modes. Experimental results show that the proposed hybrid fast macroblock mode selection algorithm promotes the encoding speed by 2.37 9.97 times without noticeable quality degradation compared with the JMVM.
Rate Distortion Optimization Based Video Coding
基于率失真优化的视频编码研究(英文)

MA Si-Wei,GAO Wen,
马思伟
,高文

中国科学院研究生院学报 , 2007,
Abstract: Rate distortion optimization technique plays an important role in video coding, which is widely used in many video coding modules, such as macroblock mode decision, quantization optimization, etc. In this paper, rate distortion optimization coding and optimal rate control are studied jointly. First, according to the analysis on the relationship between rate and distortion, a complexity scalable rate control is proposed. The proposed rate control algorithm can achieve better coding efficiency while with accurate target bit rate; second, buffer constraint for the bit allocation of rate control is studied, and the bit allocation process is adjusted to meet the buffer constraint, so that the proposed rate control algorithm can guarantee that the buffer never overflows or underflows; finally, a constant quality rate control algorithm is developed based on the research on some subjective quality issues, such as scene change detection, macroblock classification, etc.
Mean-square Error Distortion Computation Model Based on Wireless Sensor Network  [cached]
Weiming Yang,Jian Zhang,Jinxiang Peng
TELKOMNIKA : Indonesian Journal of Electrical Engineering , 2012, DOI: 10.11591/telkomnika.v10i7.1568
Abstract: On the basis of the rate-distortion theory, a new projection of the macroblock mode about the inner and mutual compiling frame is presented in this paper, and the MSE distortion computation is built. This method can acquire the optimal control point in the rate-distortion curve under the code error environment from the global optimization perspective, not only self-adaptively adjusting the quantization parameter under given network bandwidth but also refreshing inner macroblock frame according to the current probability of loss of network package, and can play an important role in counteracting the channel code error, which has a good reference value in the way of transmitting robust video code in wireless environment and allocating resources.
On Optimum End-to-End Distortion in MIMO Systems  [cached]
Jinhui Chen,Dirk T. M. Slock
EURASIP Journal on Wireless Communications and Networking , 2009, DOI: 10.1155/2009/383945
Abstract: This paper presents the joint impact of the numbers of antennas, source-to-channel bandwidth ratio, and spatial correlation on the optimum expected end-to-end distortion in an outage-free MIMO system. In particular, based on an analytical expression valid for any SNR, a closed-form expression of the optimum asymptotic expected end-to-end distortion valid for high SNR is derived. It is comprised of the optimum distortion exponent and the multiplicative optimum distortion factor. Demonstrated by the simulation results, the analysis on the joint impact of the optimum distortion exponent and the optimum distortion factor explains the behavior of the optimum expected end-to-end distortion varying with the numbers of antennas, source-to-channel bandwidth ratio, and spatial correlation. It is also proved that as the correlation tends to zero, the optimum asymptotic expected end-to-end distortion in the setting of correlated channel approaches that in the setting of uncorrelated channel. The results in this paper could be performance objectives for analog-source transmission systems. To some extent, they are instructive for system design.
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