摘要
针对H.264中帧间模式选择算法复杂度过高的问题,论文提出一种快速帧间模式选择算法。算法采用降采样方式对SKIP宏块进行检测与预判,有效降低宏块全零检测的计算量;改进UMHexagonS算法,对宏块与宏块分割使用降采样的方式进行运动搜索,大大减少原算法中块匹配的计算量;根据子宏块运动同质性来缩小最优模式的选择区间。与采用UMHexagonS的x264帧间模式选择算法比较,所提的算法在维持原有码率与峰值信噪比基本不变的情况下,使编码时间平均减少40%,显著提高了编码效率。
Aiming at the problem that complexity of H. 264 inter frame mode decision algorithm is high, a fast inter frame mode selection algorithm is proposed in this paper. The algorithm employs down-sampling method to detect and antici- pate the SKIP macroblocks, which can effectively reduce the computation of all-zero macroblock detection. Meanwhile, the proposed algorithm applies down-sampling method to the motion estimation search procedure of macroblaock and its segmen- tations, which can greatly reduce the computation of block matching in original algorithm. And also, the proposed algorithm narrows the range of optimal mode, according to sub-macroblock motion homogeneity. When compared with the x264 inter frame mode selection algorithm using UMHexagonS, the proposed algorithm reduces about 40% encoding time on average, while keeping the original stream bit rate and the peak signal to noise ratio substantially unchanged, and significantly im- proves the coding efficiency.
出处
《计算机与数字工程》
2015年第9期1662-1667,共6页
Computer & Digital Engineering
