Color image enhancement using brightness preserving dynamic histogram equalization

Histogram equalization (HE), although one of the most popular techniques used for digital image enhancement, is not very suitable to be implemented directly in consumer electronics, such as television, because this method tends to produce an output with saturation effect. To overcome this weakness, it is suggested that the mean intensity of the input image be maintained in the output image. Previously, we proposed a method known as brightness preserving dynamic histogram equalization (BPDHE) which can fulfill this requirement for grayscale images. In this paper, we present several possibilities to extend this method for color images.

I. Introduction

Image enhancement is one of the most interesting and important issues in digital image processing field. The main purpose of image enhancement is to bring out details that are hidden in an image, or to increase the contrast in a low contrast image [1]. Image enhancement produces an output image that subjectively looks better than the original image by changing the pixel's intensity of the input image [2]. Generally, image enhancement enlarges the intensity differences among objects and background.