Bilock-based fine granularity scalable video coding for content-aware streaming

Video streaming is becoming more and more popular with widely used hybrid networks. The prime challenge of such applications is to deal with varying transmission bandwidth. This paper proposes a block-based fine granularity scalable (FGS) coding structure, which is a more flexible scalable video coding structure supporting content-aware streaming compared with the MPEG-4 FGS coding structure. The streaming server can conveniently implement content-aware rate allocation or content-based selective enhancement dynamically through user's interaction with the proposed scalable coding structure. Thus the streaming server can have a differentiated delivery strategy according to user's preference. However the uniform rate allocation for bit-stream truncation of the proposed block-based FGS will result in more than 2dB loss by PSNR compared with MPEG-4 FGS within quite a wide range of bit rates. A fast optimal rate allocation method is also proposed to solve this problem in this paper. The coding efficiency is improved, which can be comparable with MPEG-4 FGS coding and is even better (0.5dB) with some sequences at some bit rates.