A Sub-Image Edge Preservation method for histogram equalization
Yan‐Tsung Peng, Bing-Chuan Tsai, Shanq-Jang Ruan · 2013
Histogram equalization (HE) is widely used in image contrast enhancement. It basically equalizes the image histogram to improve the contrast of the input image. In this paper, we propose a Sub-Image Edge Preservation (SIEP) method applied to HE-based contrast enhancement algorithms to further preserve edges in the histogram-equalized images and enhance local contrast. In this method, the input image is partitioned into different sub-images and in turn, the local transform function of each sub-image is generated respectively by applying a HE-based contrast enhancement method. Moreover, it exploits the total of gradients in each sub-image to weigh each local transform function for generating a global transform function to enhance overall image contrast while preserving edges. Experimental results show the efficacy of our method for a better edge preserving rate.