A fast search algorithm for template matching based on inequality criterion

This paper presents a fast search algorithm for template matching, using the inequality between the square error distortion measure and the difference which is between the sum of template image and the sum of every possible matching block. Firstly the sums of all possible matching blocks and template are computed and sorted. Using the inequality criterion, the algorithm prunes the number of candidate matching positions. When computing the sums of blocks, the algorithm utilizes the overlapping of neighboring blocks to accelerate the calculation. Because the inequality criterion does not rely on any assumption, the search result is equivalent to the result of the full search algorithm. Experimental results show it can save 91.77% to 93.25% execution time comparing with full-search algorithm.