在高性能视频编解码算法H.264中,运动搜索过程是计算复杂度最密集的部分,也是影响系统实时性能的瓶颈。针对这一问题,文中提出一种基于参考帧提前截止的全局判决方法,即在运动搜索中和整数余弦变换前进行准全零块判决。实验结果表明,在图像质量基本不变和码率不增加的情况下,该方法可以大幅度减少运动搜索过程的计算量。 In high-performance video coding and decoding algorithm H.264, the motion search process is the most computationally intensive part, and also a bottleneck affecting the real-time performance of the system. In order to solve this problem, a global decision method based on reference frame premature cutoff is proposed in this paper, that is, the quasi-all-zero decision is made before the motion search and before integer cosine transform. The experimental results show that this method can greatly reduce the computational complexity of the motion search process with the same image quality and no increase of the code rate.