A novel edge-based criterion for determining the number of thresholds for multilevel image thresholding
Nadim Jahangir, Chin-Kuan Ho, Junaidi Abdullah · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2012
In order to determine the appropriate number of thresholds that a grey-level image should be thresholded by so that the resulting image preserves as much information as possible from the original image using the least possible bits, we propose in this paper, a novel criterion for multilevel image thresholding. The criterion is a weighted sum of within-class variance and the number of edge pixels in the thresholded image. To determine the appropriate number of thresholds, an image has to be thresholded iteratively with increasing number of thresholds by any standard thresholding method and the solution that minimizes the proposed criterion is chosen as the appropriate solution. We also present an efficient technique to compute the number of edge pixels. Experiments on a variety of real-world images show that the proposed criterion gives visually more consistent results compared to the most widely used automatic thresholding criterion proposed by Yen et al. (1995).