Method and device for color gamut mapping

A method comprising gamut mapping a current color from a first color gamut towards a second color gamut, the gamut mapping comprising, in a plane of constant hue, mapping the chroma of the current color from the first color gamut towards the second color gamut at constant lightness, the method being characterized in that the chroma mapping further comprises:

• obtaining a target color on the second color gamut boundary wherein the lightness of the target color is greater than the lightness of a color of maximum chroma of the second color gamut and wherein the lightness of the target color is lower than or equal to the lightness of a color of maximum chroma of the first color gamut;
• in case where the lightness of the current color is lower than the lightness of the target color, mapping at constant lightness the chroma of a color on the first color gamut boundary by an increasing function of chroma applied to lightness, wherein the respective outputs of the increasing function applied to the lightness of the target color and to the lightness of the black are the chroma of the target color and the chroma of the black.

A device comprising one or more processors, wherein the one or more processors are configured to perform gamut mapping of a current color from a first color gamut towards a second color gamut in a plane of constant hue, the one or more processors being further configured to:

• obtain a target color on the second color gamut boundary wherein the lightness of the target color is greater than or equal to the lightness of a color of maximum chroma of the first color gamut and wherein the lightness of the target color is lower than the lightness of a color of maximum chroma of the second color gamut;
• and
• perform chroma mapping of the current color from the first color gamut towards the second color gamut at constant lightness wherein in case where the lightness of the color is greater than the lightness of the target color, the chroma of a color on the first color gamut boundary is mapped at constant lightness by a decreasing function of chroma applied to lightness, and wherein the respective outputs of the decreasing function applied to the lightness of the target color and to the lightness of the white are the chroma of the target color and the chroma of the white.

(canceled)