Requirements for motion-estimation search range in MPEG-2 coded video

The motion-estimation search range required for interframe encoding with the MPEG-2 video compression standard depends on a number of factors, including video content, video resolution, elapsed time between reference and predicted pictures, and, just as significantly, pragmatic considerations in implementing a cost-effective solution. In this paper we present a set of experimental results that provide a probabilistic characterization of the size of motion vectors for different types of video, from well-known standard test sequences to fast-paced sports sequences to action movie clips. We study the impact of search range on compression efficiency and video quality. Finally, and on the basis of these results, we conclude with recommendations for target search ranges suitable for high-quality compression of standard and high-definition video.