改进后的算法大大减少了对于那些运动矢量为零的块的搜索冗余，同时对于运动比较剧烈的块直接进入大范围搜索。这样即提高了搜索效率，又不会使搜索结果陷入局部最优。-improved algorithm greatly reduced for those zero motion vector search block redundancy, Meanwhile, more intense campaign of direct access to block large-scale search. That