Fast intra prediction for HEVC based on pixel gradient statistics and mode refinement

摘要

High Efficiency Video Coding (HEVC), a successor to H.264, is the next generation video compression standard. To enhance the coding efficiency of video frames, 35 intra prediction modes adopted in Prediction Unit (PU) from 4×4 to 64×64 of HEVC. However, the improvement is based on the cost of rapid increased complexity performance loss. This paper proposed a Pixel Gradient Statistics (PGS) and Mode Refinement (MR) based fast mode decision algorithm. PGS use pixel gradient information to assist prediction mode selection after Rough Mode Decision (RMD). MR utilizes neighboring mode information to select most probable mode (MPM). Experiment result shows that the proposed method performs about 28% time saving with little degradation (BD-rate increase 0.53% and BDPSNR reduce 0.038) in the coding gain.