Patent ID: 8013868

Claim:
A color processing apparatus for converting a target M-dimensional color signal in an input color space into an N-dimensional output color signal in an output color space where M and N are natural numbers and N>M, the apparatus comprising: a color gamut setting unit comprising software and hardware that sets a color gamut in an output color space to which output color signals belong to, wherein: each output color signal comprises primary colorants and extra colorants, each output color signal corresponds to an input color signal belonging to an input color space, and the extra colorants of each output color signal is uniquely associated with the corresponding input color signal in the set color gamut; wherein the color gamut setting unit comprises: a first setting unit comprising software and hardware that sets a basic color gamut in the output color space, the basic color gamut in which each input color signal corresponding to the output color signal comprising the primary colorants and the extra colorants is associated with the extra colorants of the corresponding output color signal so that a phase of the input color signal corresponding to a color signal comprising the primary colorants of the corresponding output color signal is preserved; and a second setting unit comprising software and hardware that sets an extended color gamut by at least one of (i) increasing the extra colorants of the output color signals from a surface of the basic color gamut and (ii) decreasing the primary colorants of the output color signals on the surface of the basic color gamut, and in the extended color gamut, each input color signal is uniquely associated with the extra colorants of the corresponding output color signal; a first calculation unit comprising software and hardware that uniquely calculates (N−M) colorants of the converted output color signal from the target color signal with using plural color-signal pairs, in each pair, corresponding one of the (N−M) colorants of an output color signal in the output color space are associated with an input color signal in the input color space; and a second calculation unit comprising software and hardware that calculates the remaining M colorants of the converted output color signal from the target color signal and the (N−M) colorants of the converted output color signal calculated by the first calculation unit.