The Design And Implementation Of A Robust Video Coding Scheme For Internet

With the rapid development of network technology and wide use of network multimedia, video communication attains increasing attention and is widely applied. However, traditional service provided by Internet is a kind of best effort service. The bandwidth of Internet is limited and its channel disturbance, network congestion and route selection may bring the error code, packets loss, transmission delay and dithering, which will have a great effect on the quality of video communication or even make video communication incapable to go on.Practical international standards of video coding and the error control used for video communication are studied in this paper. On this basis, a robust video coding scheme facing Internet is proposed to improve the tolerance degree to error network environment for video communication and decrease the bad effect on the quality of video communication brought by packets loss and transmission delay. This scheme is based on the combination of traditional transform coding and prediction coding on motion compensation. And then RTP/RTCP is adopted to conduct information feedback, which makes associated error control in the coder and decoder. Also, the quality of reconstructed images and the calculation cost of Duplex Pyramid Algorithm, used in coding scheme as the key error images reconstruction algorithm, are analyzed and modified in the paper.With the guide of robust video coding scheme proposed in this paper, a video coding software prototype is designed and implemented. And on the basis of this, simulations are made combining NS2. The experimental results show that the scheme proposed in the paper can keep video communication work normally under the condition of high packets loss rate and can assure that the quality of video images is acceptable at a certain extent.