1. A method of processing color information of an image in an image processing system, said image having a plurality of pixels, said method comprising: A) determining a representative color value for each pixel in said image such that a first plurality of representative color values is determined, at least one pixel in said plurality of pixels having a color value which is not equal to its representative color value in said first plurality of representative color values said first plurality of representative color values corresponding to a plurality of color volume elements which together contain at least a portion of a color space; B) providing an index value for each pixel in said image, each index value representing a particular representative color value in said first plurality of representative color values; C) processing said image by modifying said first plurality of representative color values.