Efficient Search Algorithm for Block Motion Estimation

Motion estimation is a key problem in video processing and computer vision. Optical flow motion estimation can achieve high estimation accuracy when motion vector is small. Three-step search algorithm can handle large motion vector but not very accurate. A joint algorithm was proposed in this paper to achieve high estimation accuracy disregarding whether the motion vector is small or large, and keep the computation cost much lower than full search. Since compressed digital video signals are transmitted, motion estimation is the most important technique for exploiting the temporal redundancies of natural video scenes. This technique is able to improve compression ratio, such these encoders can compress a digital video signal more than 100 times.