A new prediction search algorithm for block motion estimation in video coding

Motion estimation plays an important role for the compression of video signals. This paper presents a new prediction search algorithm (PSA) for block motion estimation. The proposed method utilizes the linear weighting of the motion vectors of the three adjacent blocks to obtain a prediction motion vector, namely, the initial search point. Using a 3x3 movable search window, it then searches from the prediction point with a fixed search step size of one until it reaches the boundary of search area or its local minimum point lies in the center of search window. Based on the spatial characteristics of the center-biased distance between a motion vector and the corresponding prediction vector and the temporal correlation of motion vectors, this method can significantly reduces search times. Simulation results show that the proposed PSA is better than the three-step search algorithm and the four-step search algorithm in terms of MSE with smaller computational requirement.