The redistribution of color values from an input device (e.g. color scanner or printer) to fit the smaller or larger gamut of the output device.
If the input gamut is larger than the output gamut, gamut mapping is the same as Gamut Compression. If the input gamut is smaller than the output gamut, colors and contrast can be intensified through Gamut Expansion, or colors can be mapped to their exact equivalents, e.g. for digital proofing.