Patent ID: 8749591

Claim:
An apparatus for processing image to supply a luminance control signal to light sources corresponding to a plurality of colors, and to supply a conversion image to a light modulation device which modulates a transmittance or a reflectance of lights emitted from the light sources, comprising: a luminance calculating unit configured to calculate luminances of the light sources by using an input image; a maximum value detecting unit configured to detect a maximum value that is the largest value in the luminances of the light sources of the plurality of colors; a luminance correcting unit configured to correct the luminances of the light sources to obtain corrected luminances of the light sources so as to reduce a difference among the luminances of the light sources of the plurality of colors, if the maximum value is smaller than a predetermined threshold value; a function calculating unit configured to calculate a gradation conversion function applied to the input image corresponding to each of the plurality of colors, by using the corrected luminances of the light sources; and a control unit configured to convert the input image into the conversion image by using the gradation conversion function, configured to supply the conversion image to the modulation device, and configured to generate the luminance control signal by using the corrected luminance of the light sources, wherein the predetermined threshold value is smaller than a half of a maximum allowable value for the luminances of the light sources.