Image contrast enhancement based on a three-level adaptive inverse hyperbolic tangent algorithm
Cheng-Yi Yu, Yen‐Chieh Ouyang, Tzu‐Wei Yu · Journal of the Chinese Institute of Engineers · 2012
An image contrast enhancement algorithm using a three-scale adaptive inverse hyperbolic tangent (3SAIHT) scheme is proposed. It has long been known that the human vision system heavily depends on details and edges in understanding its perception of scenes. The main goal of this article is to develop a contrast enhancement technique to restore a blurred and dark image so as to improve visual quality. The proposed technique consists of two steps, sub-scaling and contrast enhancement where the sub-scaling is performed by sub-band processing, while the contrast enhancement is accomplished by an AIHT algorithm to bring out hidden details in a processed image. Experimental results show that the proposed method performs better than other techniques.