Method for motion estimation in video coding

Abstract

A method for motion estimation for use in video coding. In a predetermined search region, three starting rows are chosen, wherein a given prediction point is on the middle row, the N-th row. The method includes the following steps. (a) All points of the (N−2)-th, N-th, and (N+2)-th rows are chosen as checking points. (b) Block match errors for the checking points are calculated and a checking point which corresponds to a minimum block match error is defined as a candidate checking point. (c) A determination is made whether the candidate checking point is on the N-th row; if so, the method proceeds to step (g); otherwise, it proceeds to step (d). (d) It is determined that whether the candidate checking point is on the (N+2)-th row; if so, the method proceeds to step (e); otherwise, it proceeds to step (f). (e) N is incremented by two, all points of the (N+2)-th row are chosen as checking points, and step (b) is repeated. (f) N is decremented by two, all points of the (N−2)-th row are chosen as checking points, and step (b) is repeated. (g) All points of the (N−1)-th and (N+1)-th rows are chosen as checking points, block match errors for the checking points are calculated, and a checking point corresponding to the minimum block match error is defined as the candidate checking point, wherein the candidate checking point is used for determining the motion vector for video coding.