快速HEVC帧间预测编码单元深度选择算法

Fast Coding Unit Depth Selection Algorithm for Inter-frame Prediction of HEVC

为提高编码效率,提出一种快速CU(Codizy Unit)深度选择算法。首先,计算当前CU的平均深度预测值(MPD:Mean Predrition Depth),根据MPD值对当前CU进行初步分类以减少CU深度选择的冗余遍历;然后,根据获得的参考帧同位置CUcol(Co-located CU)的率失真(RD:Rate Distortion)代价与其深度总和的比值作为参数对当前CU深度选择做进一步终止判断。实验结果表明,与原始算法HM16相比,快速CU算法在平均比特率减少0.10%,峰值信噪比仅降低0.08 d B的情况下,编码平均时间减少了59%,与文中参考文献[9]和文献[13]算法相比,编码时间平均减少了11%,有效降低了编码复杂度,提高了编码效率。

In order to improve the encoding efficiency, this paper proposes a fast CU （Codizy Unit） depth selection algorithm. First, the MPD （Mean Prediction Depth） of current CU is calculated and then the current CU is classified based on MPD so as to reduce the redundant traversal. Secondly, the CU depth of current CU is judged further for stop based on the ratio of the RD （ Rate Distortion） cost of the collocated CUco1 （ Co-located CU） with the reference frame to the total sum of depth. Experimental result shows that the proposed method decreases the average encoding time by 59% under the condition of decreasing bit rate by 0.10% and decreasing PSNR by 0.08 dB,while compared with the reference algorithm in this paper, the encoding time is reduced by 11% on average, and decreases the encoding complexity and improves the encoding efficiency.