Motion Vector Prediction Based On NMVC And Research On Error Concealment Strategy

With the expanding of wireless communication bandwidth and rising of data transmission rate, the human being is no longer satisfied with the audio and data services only. So the video communication has been one of the hotspot in the wireless communication area. Furthermore, the coding, storage, processing of video are the core areas of the video communication. Supported by the national high technology research and development program of China (863 Program)–Joint Source-Channel Coding (No: 2002AA119010), this thesis focuses on the two key technologies of wireless video communication, namely motion vector estimation and error concealment. Firstly, an overview of the characteristics and key technologies of wireless video communication is given,which illuminates the research content of this dissertation. Then, a detail analysis of why motion vector estimation is needed and how it works is carried out. A comparison of the common-used motion vector estimation algorithms based on simulation results is made. And then,a novel motion vector estimation algorithm based on the correlation of neighboring blocks is proposed. Experiment results show that this algorithm can raise the PSNR and decrease the bitrate compared with median algorithm. After that, error concealment technologies, an error control method which does not burden the codec, are reviewed. Then an analysis of the advantage and disadvantage of the traditional methods is given. A block shuffle method based on Arnold Transformation, which is traditionally used in Digital Watermark, is put forward for the preprocessing of error concealment. Experiment results show that it can improve the performance of error concealment algorithm. Then, an adaptive error concealment strategy is proposed. For the reason that it combines the advantages of traditional error concealment methods, it can achieve better video quality. Then a full discussion of the development of video coding standards and the Audio Video Coding Standard (AVS for short)——the first national audio and video coding standard China is establishing, is made. A deep analysis on AVS system layer is given, and a multiplex method for AVS system layer is proposed. The method is adopted by AVS workgroup and is written into the draft of AVS1.0 standard, part 1 system layer.