Patent ID: 7663641

Claim:
A method of performing gamut-mapping of a source point for a source device to a destination point for a destination device in a perceptually linear color space, comprising: a computer processor executing a computer program to perform the steps of: separating the source point into primary color components (Red, Green, Blue); determining tristimulus values for each of the separated primary color components, and converting the tristimulus values for each primary color component into respective device-independent color appearance space values; for each primary color component, performing a mapping process comprising the steps of: determining a source hue angle and a destination hue angle for the source point; obtaining a source cusp point representing a maximum chroma value on a source gamut boundary surface at the source hue angle, and obtaining a destination cusp point representing a maximum chroma value on a destination gamut boundary surface at the destination hue angle; performing a cusp mapping process to map the source gamut boundary surface at the source hue angle so that the source cusp point coincides with the destination cusp point; and if after the cusp mapping process, the source point lies outside of the destination gamut boundary surface, mapping the source point to the destination gamut boundary surface; converting the mapped source point obtained as a result of the mapping process for each respective primary color component from device-independent color appearance space values to tristimulus values; summing respective tristimulus values for each primary color component to obtain a resultant tristimulus values; and converting the resultant tristimulus values to a color space of the destination device to obtain a destination image.