Fast block matching based on multi-resolution motion estimation for discontinuity blocks

We propose a fast block matching algorithm for discontinuity blocks. The algorithm uses the sub-SAD value (i.e. the sum of difference divided by 4) to identify the discontinuity region, and produces an additional motion vector for the sub-blocks if necessary. Through discontinuity matching, image quality can be enhanced by reducing discontinuity error. We applied this scheme to multi-resolution motion estimation owing to its regularity at each level, which is appropriate for the sub-SAD values. The spatial distribution characteristics of motion vectors used in the proposed algorithm can make this scheme produce early output. We show with experimental results that, in comparison with some conventional motion estimation algorithms, the proposed algorithm achieves quality enhancement, especially for sequences with discontinuity blocks, and also with reduced computational complexity.