<title>Color image enhancement in a new color space</title>

Abstract

A practical approach to developing color image enhancement algorithms is to transform the R, G, and B components of each pixel into another set of color coordinates with which luminance, hue, and saturation of color can be described. Each of the new set of coordinates is processed with its own enhancement algorithm, and the enhanced new set of coordinates are inverse transformed to R, G, and B components for display. In this paper, we introduce a new color space based on a concept of nonlinear color differences. The transformations between the proposed color space and the RGB color space are much simpler than those between the LHS and the RGB color spaces. Meanwhile, the chromatic components are totally uncorrelated with the achromatic component, with which hue and saturation of color can be exactly described. With the proposed color space obtained by modifying the YIQ color space, we develop some color image processing algorithms for luminance component equalization, saturation equalization, and color emphasis.