Block matching algorithm based on local codirectionality of blocks

In this paper based on statistical analysis performed on a number of video sequences with different motion characteristics, we show that strong correlation exists between the direction of motion of a block and those of its neighboring blocks. Secondly, we show that a block moves in the same direction as a neighboring block that its prediction vector produces least distortion. Based on these findings an algorithm is proposed which adaptively determines the direction of motion of a block based on the motion direction of its neighboring blocks. The algorithm almost always avoids trapping into local minima. Test results show that in terms of speed and performance the proposed algorithm is superior to many of the existing fast algorithms.