New fast-search algorithm for block matching motion estimation using temporal and spatial correlation of motion vector

This paper introduces a new technique that reduces the search time and impr oves the motion estimation accuracy by using the high temporal and spatial correlation of a motion vector. Instead of using a fixed first-search point , as in previous search algorithms, the proposed method identifies a more a ccurate first search point through compensating the search area based on th e temporal and spatial correlation of a motion vector. Accordingly, the pro posed algorithm is based on the consistent directivity and center-biased di stribution property of a motion vector. As a result, the performance of the motion estimation is improved and the total number of search points used t o find the motion vector of the current block is significantly reduced. Sim ulation results showed that the PSNR values improved up to 3.6dB, depending on the image sequence, and advanced on average by about 1.7dB. The compara tive results demonstrated that the performance of the proposed algorithm wa s better than those of other fast-search algorithms whether the image seque nce contained fast or slow motion, and similar to the performance of a full -search (FS) algorithm. Furthermore, the performance of the proposed scheme produced a superior subjective picture quality compared with other fast-se arch algorithms.