Bit-Rate Allocation for Broadcasting of Scalable Video Over Wireless Networks

摘要

Scalable video coding technique has been desired for many years to fulfill the requirement of reliable transmission of video over heterogeneous networks. It allows for simple solutions in adaptation to network constraint and user capabilities by providing a full scalability including temporal, spatial and quality scalability. Various coding structures will dramatically affect the overall performance of the system. In this paper, we develop a new joint source and channel coding scheme for wireless broadcasting making use of H.264/SVC considering the various clients' statistics such as the accessing bandwidth and the error rate. First, an effective algorithm is carried out to distribute proper amount of source codes and channel codes to the base layer to guarantee that all the clients can receive the video with a minimum quality. Second, to deal with the burst packet loss, we propose to apply the unequal error protection (UEP) scheme on the enhancement layers using the interleaved packetization to make sure that all the lower layers can be decoded if an enhancement layer is correctly received. To maximize the system-defined utility function, fast algorithms are designed to dynamically allocate the source coding rate and the channel coding rate for the scalable bit-stream given the clients' distribution. Experiments are conducted to verify the performance of the proposed algorithm against the other two schemes, where equal error protection (EEP) and UEP schemes with different coding structures are employed. The results demonstrate the superiority of the proposed scheme and the improvement is up to 2 dB.