基于 MPEG-4 的视频联合信源信道编码

A new robust joint source channel coding method for MPEG-4 video over noisy channel is proposed. In the method, the base layer bit streams are reordered according to their relative importance and then interlaced packetized. Multiple sub-layers of texture information are generated based on their rate distortion function, the number of which is adjusted dynamically by the encoder according to the feedback information to minimize the overall distortion. Simulation results show that the method has the performance obviously higher than that of un-protected MPEG-4, and can be more stable than MPEG-4 equal error protection method under the same conditions of bandwidth and packet loss rate. Since the method makes joint optimization to the number of transmission sublayers and the protection level according to the feedback parameter, it can be more adaptive to the channel situation and can obtain higher performance compared with MDFEC method proposed by Puri, which design the object functions and performs optimization according to the fixed channel situation.