Source colors are mapped within a mapping segment starting at a preserved gamut boundary color (PC) and ending at a target gamut boundary color (IT-C) of the chromaticity plane, corresponding, in a linear 3D color space, to an intersection of the target color gamut (TCG) with a plane of constant luminance and with a mapping plane (MKO) comprising said source color (M), a black point (K) and a white point (O).