Eight-Scale Image Contrast Enhancement Based on Adaptive Inverse Hyperbolic Tangent Algorithm

Algorithms

Cheng-Yi Yu²  Chi-Yuan Lin²  Sheng-Chih Yang²  Hsueh-Yi Lin¹ 

[1] Department of Computer Science and Information Engineering, National Chin Yi University of Technology, Taichung 41170, Taiwan;

关键词: eight-scale;    sub-band;    adaptive inverse hyperbolic tangent;    contrast enhancement;   

DOI  :  10.3390/a7040597

来源: mdpi

【 摘 要 】

The Eight-Scale parameter adjustment is a natural extension of Adaptive Inverse Hyperbolic Tangent (AIHT) algorithm. It has long been known that the Human Vision System (HVS) heavily depends on detail and edge in the understanding and perception of scenes. The main goal of this study is to produce a contrast enhancement technique to recover an image from blurring and darkness, and at the same time to improve visual quality. Eight-scale coefficient adjustments can provide a further local refinement in detail under the AIHT algorithm. The proposed Eight-Scale Adaptive Inverse Hyperbolic Tangent (8SAIHT) method uses the sub-band to calculate the local mean and local variance before the AIHT algorithm is applied. This study also shows that this approach is convenient and effective in the enhancement processes for various types of images. The 8SAIHT is also capable of adaptively enhancing the local contrast of the original image while simultaneously extruding more on object details.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.