Image processing apparatus and profile generation method

摘要

When a grid point that is the object to be mapped is present in a first division region a color of which has lightness equal to or higher than the lightness at the maximum chroma point in the color gamut and has chroma higher than the chroma at that point, the intersection of a straight line connecting the grid point to the maximum chroma point and an achromatic axis is calculated and a point having lightness equal to or higher than the lightness of the intersection is set as the focal color. Then, the intersection of a straight line connecting the object grid point to the focal color and the boundary of color gamut is set as an output color for the grid point. The output colors are prevented from being separated into color on the high and on the low lightness sides with respect to the maximum chroma point.

主权项

1. An image processing apparatus that generates a profile for, in a color space, converting a color of a grid point defined in a first color gamut into a color in a second color gamut by mapping the color of the grid point to a color on a straight line connecting the color of the grid point to a focal color on achromatic axis, said apparatus comprising:
a determining unit configured to determine whether or not the color of the grid point belongs to a predetermined region, a color in which has lightness higher than the lightness at a maximum chroma color in the second color gamut and has chroma higher than the chroma at the maximum chroma color in a plane of a hue of the color of the grid point in color space; a converting unit configured to perform mapping the color of the grid point defined in the first color gamut; and a profile generation unit configured to generate the profile based on a result of the conversion of each of a plurality of the color of the grid point, wherein in the case that said determining unit determines that the color of the grid point belongs to the predetermined region, said converting unit sets, as the focal color, a color having lightness equal to or higher than lightness at an intersection point of an achromatic axis and straight line connecting a point of the color of the grid point to a point of the maximum chroma color, and performs the mapping of the color of the grid point.