Research Of H.264 Error Concealment Algorithm

In recent years, with the rapid development of the network technology and multimedia technology, digital video information containing the massive data information which need the huge bandwidth resources to transmit, brings huge challenge to information storage and transmission. Because video information data contains massive data information, we have to compress them efficiently, but the compressed data stream is particularly sensitive to channel error, leading to errors spreading easily in spatial and temporal domain, which will seriously affect video quality. Therefore, in the case of errors have occurred, concealing errors of video information is particularly important,people pay special attention to the research of error concealment which will also have important practical value.Compared with previous video coding standards, H.264/AVC has higher coding efficiency, clearer image quality, better network adaptive and more powerful error resilient technology. Firstly,this dissertation describes the development of video coding standards and the basic concepts of error concealment technology, then introduces the structure of H.264 video coding standard features, quality and level of codec framework, key technologies and highlight the H.264 error recovery technology,then introduces the commonly used error concealment algorithm.Finally, aiming at the deficiency of the H.264 JM reference model in the error concealment algorithm, we design a new error concealment scheme with the following three improvements:(1) Aiming at the deficiency of the spatial error concealment for JM86 algorithm, this dissertation proposes a new model which the weighted interpolation algorithm combines with direction interpolation algorithm. Finally, the experimental simulation results show that the proposed error concealment algorithm both in the objective quality and subjective visual effect are better than JM86 algorithm.(2) Aiming at the deficiency of the temporal error concealment for JM86 algorithm, this dissertation proposes an improved boundary matching algorithm. Finally, the experimental simulation results show that the proposed error concealment algorithm both in the objective quality and subjective visual effect are better than JM86 algorithm.(3) Aiming at the deficiency of JM86 algorithm does not deal with scene change, this dissertation proposes an concealment algorithm based on scene change. if scene change occurs, improved spatial error concealment algorithm is adopted,else improved spatial error concealment is chosen., The simulation show that this improved error concealment can detect and deal with scene change effectively.