An efficient early-termination mode decision algorithm for H.264

We present a novel early-termination motion estimation scheme specifically designed for the H.264 standard. Our method takes advantage of correlation between the rate-distortion cost of the 16times16 pixel motion search and the cost of the potential best choice for the block size in order to terminate the motion search before all possible options have been checked. A pixel decimation method yields additional reduction in computational complexity. The method is suitable for supplementing various existing fast motion estimation algorithms. When supplementing the EPZS method [1] presently used in H.264, our method achieves total computational savings of 55% for almost the same picture quality, and a slight increase in bitrate.