In order to implement color matching between different printers upon proofing or the like, color processing that absorbs not only a difference between gamuts but also differences among white, black, and a gray line is provided. Two pieces of gamut information of an appearance color space of first and second image devices are acquired. The color signals on a gray line of each gamut information are converted into those on a lightness axis of the appearance color space. A gamut indicated by the gamut information of the first image device is mapped within a gamut indicated by the gamut information of the second image device. Color signals after mapping, which correspond to a gray line of the first image device, are converted into gray color signals according to white and black indicated by the gamut information of the second image device.
Techniques relating to gamuts and gamut mapping are described. In one instance, a process identifies a gamut attribute and generates a gamut having the attribute.
