一种采用多模式切换的快速运动估计算法

摘要

Search patterns have an important influence on both searching speed and encoding quality of Block-based Motion estimation Algorithms (BMA). A fast block-based motion estimation algorithm utilizing a multi- pattern switching method is proposed, during which process a halfway stop technology and a selective search method are used to promote encoding speed. The algorithm is named Diamond-Hexagon-Square (DHS) algorithm, for a small diamond pattern is used as the initial search pattern, followed by a hexagon pattern, and a square search pattern is utilized at last for refinement. Experimental results indicate that the DHS algorithm is suitable for various video sequences with different motion contents (slow, medium and fast). It is faster than the small DIAmond search algorithm (DIA), HEXagon search algorithm (HEX), a Exhausted Search Algorithm (ESA) and Unsymmetrical-cross Multi-Hexagon-grid Search (UMHexagonS) algorithm with no obvious rate-distortion performance depravation.%　　搜索模式对于基于块的运动估计算法(BMA)的搜索速度和编码质量起着重要影响。该文提出一种多模式切换的快速运动估计算法,其采用了早停止和选择性搜索技术来提高编码速度,以小菱形作为起始搜索模式,然后过渡到六边形模式,最后使用正方形搜索模式进行细化,故命名为DHS(Diamond-Hexagon-Square)算法。实验结果表明,DHS算法对于各种运动情况(慢速、中等速度和快速)的视频序列具有普适性,在率失真性能未出现显著下降的前提下,其速度明显快于小菱形算法(DIA)、六边形算法(HEX)、穷尽搜索算法(ESA)和非对称十字形多层次六边形格点搜索(UMHexagonS)算法。