Image Contrast Enhancement by Global and Local Adjustment of Gray Levels

Na DUAN  Soon Hak KWON  

IEICE TRANSACTIONS on Information and Systems   Vol.E93-D   No.10   pp.2866-2869
Publication Date: 2010/10/01
Online ISSN: 1745-1361
DOI: 10.1587/transinf.E93.D.2866
Print ISSN: 0916-8532
Type of Manuscript: LETTER
Category: Image Processing and Video Processing
contrast enhancement,  histogram equalization,  local contrast enhancement,  

Full Text: PDF(550.9KB)>>
Buy this Article

Various contrast enhancement methods such as histogram equalization (HE) and local contrast enhancement (LCE) have been developed to increase the visibility and details of a degraded image. We propose an image contrast enhancement method based on the global and local adjustment of gray levels by combining HE with LCE methods. For the optimal combination of both, we introduce a discrete entropy. Evaluation of our experimental results shows that the proposed method outperforms both the HE and LCE methods.