H.264 Fault-tolerant Technology And Its Applications In Wireless Video Communications

In recent years, with the development of multimedia and Internet technology, kinds of information collection modes are increasing, such as widespread usage of digital cameras and video cameras, which make the source of video information expand .At the same time, as video information is intuitive, high efficiency, widely used,the market demand is expanding. The application of video such as Internet TV, video telephone, video conference is more and more popular. Video communication technology has become a hot research.However, as the video is rich in information content and amount, the network bandwith is limited, we compress video informantion and adapt suitable error resilience tools to satisfy the requirement of network transmission.The error control method of video communication system is the focus and difficulty of study.In this paper, firstly, the technology background and research status of video communication system is introduced, the key technologies of H.264/AVC video compression standard which contain video coding layer and network interface layer are analyzed.The common error control methods in video communication system are researched.The characterics of wireless channel, wireless video communication problems and the application of H.264 standard in wireless environment are analyzed. The error resilience tools of H.264 standard are key points of study.The effect of flexible macroblock ordering and error concealment is simulated, the strategies of error resilience for conversational and streaming application in wireless video communication are proposed, the simulation result is given.As the basis of deeply understanding of FMO error resilience tool of H.264 standard, the research status of FMO is analyzed, a double helix FMO mode is designed. This mode uses double helix pattern arrange macroblock, makes the adjacent macroblock of the lost macroblock be scattered in different slice group and offers an effective solution to the conflict of the error concealment and image prediction mechanism on the macrobloc arrangement issue. Simulation and experimental results show that the error resilience effect of double helix FMO is better than most of fixed FMO modes,demonstrates good network adaptability and robustness and realizes easily.Finally, according to above theory and simulation results, conclusions are made. Suggestions of further study on the research of H.264 error resilience tools are proposed, which have certain value for the study of error resilience tools of H.264 and the development of wireless video communication system.