Patent ID: 8164647

Claim:
A light source estimating apparatus for estimating a type of a light source used when an input image is picked up, the apparatus comprising: a pixel selection circuit means for selecting effective pixel data, the pixel selection circuit selecting pixels not having the pixel data of zero or near zero and selecting pixels not having the pixel data of a maximum value or near the maximum value; distribution retaining means which retains a distribution, in a predetermined space, of the selected effective pixel data picked up under a first or second light source and stores parameters for light source estimation; coordinate determining means which determines coordinates of the selected effective pixel data of the input image in the predetermined space and performs a calculation between the selected effective pixel data picked up under the first or second light source and the parameters stored in the distribution retaining means; and distribution judging means which judges distribution of the selected effective pixel data picked up under the first or second light source to which the coordinates belong, wherein an estimation result by the light source estimating apparatus is supplied to an image parameter setting means, the image parameter setting means supplying white balance gains and a color correction matrix corresponding to the estimated light source to a white balance processing means and a color reproduction processing means.