基于全局和局部残差复杂度的帧间模式选择

Inter-mode selection based on general and local residual complexity

针对H.264/AVC传统帧间模式选择算法的高复杂度,提出了一种适合各种视频分辨率格式的快速帧间模式选择算法.该算法基于全局残差复杂度(General residual complexity,GRC)和局部残差复杂度(Local residual complexity,LRC),通过GRC与QP来近似计算一个阈值,然后通过对局部残差复杂度跟该阈值比较来决定宏块的活跃度,再根据宏块的活跃度选出候选的帧间模式,由此进行率失真优化(Rate-distortion Optimization,RDO)计算,从而减少了不必要帧间模式的RDO计算,取得了较高的编码效率.实验结果表明,与JM18.4默认的帧间模式选择算法相比,该算法在峰值信噪比和码率基本不变的前提下,可以平均减少大约60%的帧间编码时间.

Considering the high complexity of traditional H. 264/AVC inter-mode selection algorithm, this paper proposes a fast inter-mode selection algorithm for different video resolution. This algorithm is based on general residual complexity （GRC）and local residual complexity（LRC）. The threshold is calculated approximately by GRC and QP and the LRC is compared with this threshold to determine the macro block activity. Then the candidate inter modes are selected according to the macro block activity and the rate distortion optimization （RDO） is calculated. It can reduce unnecessary RDO calculation in inter-mode and enhances a higher coding efficiency. Experimental results show that comparing with JM18.4 default intermode selection algorithm, this algorithm can reduce of 60% of its inter-frame coding time on average with the invariable peak signal noise ratio and coding rate.