Abstract: A fast algorithm based on interlaced extracting modes, statistics of pixel gradient and residual of sub-CU for intra prediction in High Efficiency Video Coding (HEVC) is presented in this paper. Corresponding to 33 intra angle modes in HEVC, gradient directions are divided into 33 classes. And gradient direction of every pixel in a CU is calculated. Angle modes with even number are calculated and ranked firstly, then the set of candidate mode is gained by fast comparison. According to the cumulative number of pixels in every class of gradient direction, some candidate modes can be rejected. When calculating Hadamard Transform predicted residual (SATD) of current PU, SATDs of the four sub-PUs are noted. According the relative ratio of them, the traversal calculation of next depth of current PU is rejected. Experimental results show that, compared with HM13.0, the proposed method performs about 54% time saving of intra encoding with only 1% increment on the total rate.

Key words: high efficiency video coding (HEVC); intra prediction; interlaced extracting mode; pixel gradient; residual of sub-PU; fast algorithm