Concepedia

Abstract

Histogram equalization is one of the common tools for improving contrast in digital photography, remote sensing, medical imaging, and scientific visualization. It is a process for recovering lost contrast in an image by remapping the brightness values in such a way that equalizes or more evenly distributes its brightness values. However, Histogram Equalization may significantly change the brightness of the entire image and generate undesirable artifacts. Therefore, many Histogram Equalization based algorithms have been developed to overcome this problem. This paper presents a comprehensive review study of Histogram Equalization based algorithms. Computer simulations and analysis are provided to compare the enhancement performance of several Histogram Equalization based algorithms. A secondderivative- like enhancement measure is introduced to quantitatively evaluate their performance for image enhancement.