Patent ID: 8115827

Claim:
A color processing apparatus for evaluating a gradation characteristic of a color conversion table that is used to convert signal values in input color space into signal values in output color space and has a plurality of grid points, the color processing apparatus comprising: an acquisition unit configured to acquire signal values in the output color space corresponding to four adjacent grid points in the input color space through the color conversion table; a calculation unit configured to calculate a property of a tetrahedron formed by the signal values in the output color space; and an evaluation unit configured to evaluate a gradation characteristic of the color conversion table based on the property of the tetrahedron calculated by the calculation unit, wherein the property of the tetrahedron calculated by the calculation unit is the volume of the tetrahedron, wherein the tetrahedron is obtained by dividing a cube formed by the grid points in the output color space, and wherein the calculation unit calculates the volume of the tetrahedron using inner products and outer products of vectors connecting vertices represented by the signal values in the output color space so that the volume of the tetrahedron is a positive value when the gradation characteristic is not reversed.