Two-dimensional peak filter in almost linear time

Abstract

The goal of this paper is to develop a fast algorithm for local peak filtering of two-dimensional arrays. The ambiguity of the concept of a local peak is demonstrated and additional conditions introduced that resolve it. A correct peak filter that takes into account the above conditions is developed. To evaluate effectiveness of the proposed algorithm two known algorithms for finding local maxima are described. Estimates of the computational complexity of algorithms for the best and worst cases are given. Analysis of dependency of the algorithm execution time from image size, sliding window size and a number of local maxima, is made. The results of experimental research showed that performance of the correct peak filter is higher than its incorrect counterparts.