Recursive algorithm based on fuzzy 2-partition entropy for 2-level image thresholding

The fuzzy c-partition entropy approach for threshold selection behaves well in segmenting images. But the size of search space increases very rapidly when the number of parameters needed to determine the membership function increases. The computation complexity of the fuzzy 2-partition entropy approach is bounded by O(L³). In this paper, a recursive scheme which decreases the computation complexity of the basic algorithm to O(L²) is proposed. The approach does not need the calculation of the membership function. The processing time of each image is reduced from more than 5 min to less than 20 s.