Patent ID: 6301383
Filing Date: 2001-10-09
Classification: H04N

Abstract:
An image processing apparatus for converting an image in an input system to an image corresponding to a color gamut obtained by an output system, the apparatus comprising:an input system having an input system gamut to be converted;an output signal having an output system gamut to be mapped with the input system gamut;color-gamut mapping means, which performs color-gamut mapping with respect to color signals outside the output system gamut in the direction along which the value of the following color-difference formula is minimized:.DELTA.E={(.DELTA.L*/K.sub.L).sup.2 +(.DELTA.C.sub.ab */K.sub.c).sup.2 +(.DELTA.H.sub.ab */K.sub.H).sup.2 }.sup.1/2where .DELTA.L*, .DELTA.C.sub.ab * and .DELTA.H.sub.ab * represent a lightness difference, a chroma difference and a hue difference, respectively, between the input system gamut and the output system gamut, and wherein K.sub.L, K.sub.c and K.sub.H represent predetermined constants having the following relationships: K.sub.c.gtoreq.K.sub.H and K.sub.c.gtoreq.K.sub.L.