Multi layer based rate control algorithm for HEVC
The specialized QP determination and reference picture set (RPS) mechanism in High Efficiency Video Coding (HEVC) significantly improves the coding efficiency. In this paper, we propose a frame layer rate control algorithm for HEVC based on this specialized mechanism. Firstly, we design a RPS based hierarchical partition structure. Then an efficient hierarchical bit allocation scheme is proposed. Moreover, a novel header bits ratio prediction method is also provided to further improve the accuracy of bit allocation. Finally, an improved mean of absolute difference (MAD) prediction scheme is provided for quadratic R-Q model to calculate an accurate quantization parameter. Experimental results demonstrate the proposed algorithm has much better R-D performance. Compared with the state-of-the-art rate control scheme for HEVC, the BD-Rate gain can be up to 30% and BD-PSNR gain can be 0.6dB on average in Low_Delay configuration. Moreover, our proposed algorithm also provides smaller mismatch between the target bit rate and the actual bit rate.