  A novel method of color image enhancement is proposed, in which three or four
color channels of the image are transformed to one channel 2-D grayscale image.
This paper describes different models of such transformations in the RGB and
other color models. Color image enhancement is achieved by enhancing first the
transformed grayscale image and, then, transforming back the grayscale image
into the colors. The color image enhancement is done on the transformed 2-D
grayscale image rather than on the color image. New algorithms of color image
enhancement are described in both frequency and time domains. The enhancement
by this novel method shows good results. The enhancement of the image is
measured with respect to the metric referred to as the Color Enhancement
Measure Estimation (CEME).
