Patent ID: 8396130

Claim:
A motion vector search method used in video encoding which performs motion-compensated prediction, the method comprising the steps of: inputting a motion vector which has been searched for with respect to an encoding target block; computing a motion vector having a minimum overhead cost which minimizes the amount of code generated for the motion vector of the encoding target block; limiting a search area by specifying an area interposed between the input motion vector and the computed motion vector having the minimum overhead cost, and determining the specified area to be the limited search area, in a manner such that the search area becomes larger as the distance between both vectors increases and the search area becomes smaller as said distance decreases; and searching for a motion vector by searching only the limited search area, wherein: the step of limiting a search area includes specifying a circular area having a radius which corresponds to a line segment between the input motion vector and the computed motion vector having the minimum overhead cost, and determining the specified area to be the limited search area; and the encoding target block includes a start point of both the two motion vectors, and the start point of two motion vectors is outside of the search area.