Motion vector searching method using plural search areas

A motion vector searching system and method estimates a motion vector during image compression by acquiring a present image frame and at least one previous image frame, generating low-resolution images of the present and previous frames in multiple stages, determining areas in one of the stages in which pixel searches are to be performed, locating at least two areas which overlap, and then merging the overlapping areas if a merge condition is satisfied. The search areas are determined by identifying candidate points in the low-resolution image which have low pixel absolute difference values, and the merge condition may correspond to a certain minimum distance between centers of the overlapping areas. A motion vector estimator is used to perform additional searching in the merged and non-merged areas to generate a motion vector associated with the present and previous image frames. Through at least the merging step, the motion vector searching system and method are able to achieve improved performance in terms of computational efficiency.