一种低复杂度的HEVC帧内快速编码算法

为了降低高效视频编码(HEVC)帧内编码复杂度,提出一种HEVC帧内快速编码算法。根据视频图像的纹理复杂性,提前跳过或者中止部分尺寸的编码单元(CU)的划分,减少CU深度遍历区间;同时,根据粗选过程后预测模式和代价值的统计特性采用阈值法或者梯度模式直方图法进一步筛选掉粗选后可能性较小的预测模式,从而减少最后进行率失真(RD)代价计算的帧内预测模式数量,进一步降低编码复杂度。实验结果表明,本文算法与HEVC原始平台相比,在全I帧编码模式下编码时间平均减少42.20%,码率(BR)上升约1.75%,峰值信噪比(PSNR)降低了0.108dB,有利于实时应用。

A fast intra coding algorithm with low complexity for HEVC

In order to reduce the intra encoding complexity of high efficiency video coding (HEVC),a fast intra encoding algorithm is proposed. According to the video image texture complexity,the algorithm can skip ahead or suspend some coding units division of corresponding size,and reduce depth traversal interval.At the same time,based on statistical data of intra prediction modes and cost after the process of rough mode decision,the algorith m uses the method of threshold or gradient mode histogram to exclude the intra prediction modes of small possibili ty,then reduces the number of intra prediction modes for the rate-distortion cost calculation and further cut down the encoding complexity.The experimental results show that compared with the original HEVC encoding algorith m,the proposed algorithm can reduce encoding time by 42.20% on average,with a bit rate (BR) increase of 1.75% and a peak signal-to-noise ratio (PSNR) loss of 0.108dB,which is in favor of real-time applications.