H.266/VVC中一种改进的仿射运动估计算法

An Improved Affine Motion Estimation Algorithm in H.266/VVC

通用视频编码标准H.266/VVC通过引入多种新的编码技术,如仿射运动补偿预测、自适应运动矢量精度、多核变换等,以支持360°视频和HDR视频的编解码,从而为用户提供最优的视频质量,但是在H.266/VVC帧间预测过程中,仿射运动估计计算复杂度高导致编码时间显著增加。针对该问题,提出一种改进的仿射运动估计算法。通过对仿射高级矢量预测(AAMVP)候选列表的构建过程进行改进,并构建一种AAMVP候选列表候选项筛选准则,使得列表的候选项更接近编码块真实的运动矢量,从而缩短编码时间。同时对仿射运动估计中迭代搜索最优仿射运动矢量的迭代过程进行优化,以加快迭代搜索速度。实验结果表明,在低时延的编码器配置下,相比VVC原始算法,当BD-BR增加了0.023%时,该算法的总体编码时间平均缩短13%,在保证编码质量的前提下能够有效降低编码的计算复杂度。

The universal video coding standard H.266/VVC introduces a variety of new coding technologies,such as affine motion compensation prediction and adaptive coding motion vector accuracy,multi-core transformation. It supports the encoding and decoding of 360° video and HDR video,providing users with the best video quality. During the interframe prediction of the H.266/VVC,the high computational complexity of affine motion estimation significantly increases the coding time. An improved affine motion estimation algorithm is developed in this study to solve this problem. The construction process of the Affine Advanced Motion Vector Prediction(AAMVP) candidate list is improved,and a selection criterion for the AAMVP candidate list is constructed.The list candidates are closer to the real motion vector of the coding block,shortening the coding time.The process of iteratively searching for the optimal affine motion vector for affine motion estimation is optimized to accelerate the iterative search.The experimental results show that when the BD-BR increases by 0.023% under low-latency encoder configuration compared with the original versatile video coding algorithm,the overall encoding time of the algorithm decreases by an average of 13%. The proposed algorithm can effectively reduce the computational complexity of encoding while ensuring encoding quality.