Detail preserving reproduction of color images for monochromats and dichromats

An effective gray-scale conversion method should preserve the detail in the original color image. The fundamental premise is that this is best achieved by a perceptual match of relative color differences between the color and the gray-scale images. Specifically, the perceived color difference between any pair of colors should be proportional to their perceived gray difference. A new approach to the gray-scale conversion problem that is built on this premise is proposed. The method automatically constructs a linear mapping that depends on the characteristics of the input image and incorporates information from all three dimensions of the color space.