关键词: 帧内预测, 统计结果, 梯度模式直方图, 模式选择

Abstract: In view of the intra encoding computational complexity of HEVC, a fast intra prediction mode decision algorithm is proposed. Based on statistical data, for prediction units of large size, the algorithm uses threshold method to exclude the intra prediction modes of small possibility. When the size of prediction unit is small, according to the distribution of cost, the algorithm reduces the number of the intra prediction mode directly or uses the method of gradient mode histogram to exclude the intra prediction modes of small possibility, then reduces the number of intra prediction modes for the rate-
distortion cost calculation and cuts down the encoding complexity. The experimental results show that the proposed algorithm can improve the HEVC encoding speed greatly with a negligible image quality degradation and average bit-rate increase, which is in favor of real-time applications.

Key words: intra prediction, statistical results, gradient mode histogram, mode decision