一种方向延伸的快速运动搜索算法

A Fast Direction Extensible Motion Estimation Algorithm

利用图像块运动的方向特性,减小帧间编码中运动估计的运算量。该算法利用小模板钻石搜索,先确定中心检测点到最小块失真检测点为搜索方向,然后在此方向上不断延伸一个检测点进行块失真匹配,直至下一个检测点的块失真大于当前检测点的块失真。接着以当前检测点作为中心检测点,重复以上操作,直至中心检测点为最优检测点,结束搜索。搜索中利用自适应门限提前退出搜索。搜索速度比钻石搜索算法提高了20%～60%。

The algorithm reduces the calculation complexity of motion estimation by using the block motion direction characteristic. Firstly, the algorithm does once Small Diamond Search Pattern （SDSP） to confirm the direction from the Center Search Point to the current least block distortion point to be the search direction. Secondly, does the block-matching in the next search point continuously until the next search point＇s block distortion becomes larger. Then the algorithm regards the current search point to be the Center Search Point and repeat the above operation until the Center Search Point is the least block distortion point. In the process of block-matching, two adaptive thresholds are used to cease the search. Experimental results show that the algorithm＇s search speed improves by 20%-60% compared with Diamond Search Pattern under the same conditions.