Patent ID: 8526736

Claim:
An image processing apparatus comprising: an illumination light component estimation unit which calculates an estimated illumination light component of an original image; an estimated illumination light component correction unit which outputs a corrected estimated illumination light component obtained by correcting the estimated illumination light component; a Retinex processing unit which corrects a luminance component of the original image by dividing the luminance component by the corrected estimated illumination light component, and a gain adjustment unit which adjusts gain of the corrected luminance component, wherein the estimated illumination light component correction unit converts an estimated illumination light component having a value from 0 to a reference value into a maximum value of the corrected estimated illumination light component, converts an estimated illumination light component having a value greater than the reference value such that the value of the corrected estimated illumination light component becomes greater than the value of the estimated illumination light component, and uses a property in which an increasing ratio of the corrected estimated illumination light component is decreased as the value of the estimated illumination light component is increased.