Research On Error Concealment Techniques Of H.264 Compression Coding

The digital television, new technologies of the flourishing industries such as 3G, high density storage in family consumption electronics, all of them are based on development of audio and video compression and transmission. The new video coding standard H.264 come up under this situation, which has already received wide attentions in the industry and academic study because of its better performance in compression efficiency, image quality and network adaptability. And now it is considered to be one of the most promising video coding standards in the future.It is impossible to avoid transmission error as interruption and delay happen in channel. Since highly compressed video information is very sensitive to interference, and H.264 uses many new technologies, such as intra prediction, multi-reference-frame motion estimation and so on, while these new features also bring new challenges for error concealment, error resilience becomes significant in video transmission. Based on the analysis of video coding standard H.264, this paper mainly focuses on the post processing technique which is knows as error concealment. Here is the major content of the paper:Firstly, this thesis introduces the theory of video compression coding and the process of video compression. Around error concealment the heart of this thesis, this thesis analyses the thinking behind the design of H.264 and the coding process, and discusses the key technology in H.264 coding standard.Secondly, this thesis introduces the classic algorithms about error concealment, and discusses the characteristic of each algorithm. The framework of reference software JM is analyzed, and particularly introduced the error concealment module which is to be improved in this thesis.Thirdly, this thesis researches the error concealment algorithms of H.264. Considering the inter coding features of H.264, a novel temporal error concealment algorithm for H.264 based on multi division mode adaptive overlapping is proposed. In this algorithm, EBMA is improved first, then the corrupted MB is concealed several times, each with different division mode, and the SAD of each mode is calculated. According to the value of SADs, two MBs with smallest SAD and second smallest SAD are weighted overlapping adaptively to conceal the lost MB. The simulation results show that, compared with the traditional algorithm, this algorithm has better performance of concealment in both objective and subjective evaluations.Verifying the new algorithm on JM90 which is the standard test platform of H.264, results show that the presented schemes have certain advantage and practicality.