International Journal of Computer Applications |
Foundation of Computer Science (FCS), NY, USA |
Volume 55 - Number 4 |
Year of Publication: 2012 |
Authors: Saruchi |
10.5120/8747-2634 |
Saruchi . Adaptive Sigmoid Function to Enhance Low Contrast Images. International Journal of Computer Applications. 55, 4 ( October 2012), 45-49. DOI=10.5120/8747-2634
Image enhancement is one of the most important issues in low-level image processing. Mainly, enhancement methods can be classified into two classes: global and local methods. Various enhancement schemes are used for enhancing an image which includes gray scale manipulation, filtering and Histogram Equalization (HE). Histogram Equalization (HE) has proved to be a simple and effective image contrast enhancement technique. In this paper, the global histogram equalization is improved by using sigmoid function combined with local enhancement statistics. Experimental results demonstrate that the proposed method can enhance the images effectively. The performances of the existing techniques and the proposed method are evaluated in terms of SNR, PSNR, CoC.