Patent ID: 7421119

Claim:
A light source presuming method of presuming a light source color of image data, comprising the steps of: obtaining candidate light source color as candidates for the light source color of said image data; obtaining parameters of a color adaptation model showing color adaptation of a sense of sight from said obtained candidate light source color to a predetermined reference light source color so as to be guided to parameters of a color adaptation model showing color adaptation of the sense of sight from known guide light source color to said reference light source color; obtaining light source color, as correction candidate light source color, having a relation of the color adaptation of the sense of sight with said reference light source color in a model state shown by said obtained guide parameters, substituting said correction candidate light source color for said candidate light source color, and converging errors included in said candidate light source color; and presuming the correction candidate light source color whose errors are minimized by the convergence as a light source color of said image data.