System and method of gamut mapping image data

A method of out-of-gamut predetermination in which an original RGB color value, having a corresponding gamut range M, is transformed to obtain an original luminance value, the original luminance value having associated original chrominance value, and wherein the original luminance value is processed to obtain a processed color value having a processed luminance value and the original chrominance values, the method comprising:

• determining a difference between the processed luminance value and the original luminance value;
• making the out-of-gamut predetermination using only the original RGB color value, the gamut range M, and the difference.

A system of processing image data having a plurality of color values in an original color space, wherein an original color value of the plurality of color values is transformed to obtain an original luminance value, the original luminance value having an associated luminance/chrominance based color space and original chrominance values, and wherein the original luminance value is processed to obtain a processed color value having a processed luminance value and the original chrominance values, the system for mapping the processed color value into the original color gamut comprising:

• a selector for selecting a target color value on a luminance axis, wherein a different target color value is selectable for each of the plurality of color values;
• a color value mapper for determining a mapped color value by linearly projecting from the processed color value towards the target color value, the mapped color value being located at the intersection of a gamut boundary of the original color space and the projection.

A computer readable medium for causing a processor in a computer system to perform processing instructions for mapping a processed color value into an original color gamut, the processed color value having an associated original color value of a plurality of color values of image data in the original color space comprising:

• selecting a target color value on a luminance axis, wherein a different target color value is selectable for each of a plurality of color values of the image data;
• determining a mapped color value by linearly projecting from the processed color value towards the target color value, the mapped color value being located at the intersection of a gamut boundary of the original color space and the projection.