关键词: 分布式视频编码, 无反馈, 大图像组, 编码端码率控制, 边信息更新

Abstract: To avoid the severe decoding delay caused by the interpolating structure based Distributed Video Coding（DVC） under condition of long Group of Pictures（GOP）, this paper studies feedback-free DVC based on extrapolation structure. At encoder, an Unequal Protection Encoder Rate Control（UP_ERC） algorithm is proposed. In which fast motion compensated extrapolation algorithm is used to obtain high quality side information estimation at the encoder, and then a bitplane-level rate control algorithm is achieved according to error probability and the importance of each bitplane. In addition, a side information refinement based on extrapolation and interpolation is proposed at decoder, utilized in the iterative decoding process to enhance the quality of the estimated frame. Experimental results show that, the proposed method provides a more precise encoding rate compared to other existing feedback-free algorithms, with a rate-distortion performance increasement by 0.6~1.8 dB. Furthermore, it also gets significant improvement on the subjective quality.

Key words: Distributed Video Coding（DVC）, feedback-free, long Group of Pictures（GOP）, encoder rate control, side information refinement