Patent ID: 7750948

Claim:
An image signal processing device that processes an image signal constituting a subject image captured by an image-capturing element, comprising: an average calculating unit that calculates pixel output averages for individual colors in each of a plurality of partition areas into which a light-receiving surface of the image-capturing element is divided based upon the image signal; an average ratio calculating unit that calculates a ratio of a pixel output average corresponding to another color to a pixel output average of a reference color for each partition area; an area extracting unit that extracts an area having a ratio of pixel output averages within a predetermined range; and a white balance adjustment unit that performs a white balance adjustment based upon pixel outputs corresponding to the individual colors from the extracted area; wherein the white balance adjustment unit includes: a total sum calculating unit that calculates total sums of pixel output averages corresponding to the individual colors in the extracted area; a gain calculating unit that calculates a white balance gain for a color other than the reference color based upon the total sums corresponding to the individual colors; and a pixel output adjustments unit that performs white balance adjustments by multiplying pixel outputs corresponding to the color other than the reference color by the white balance gain.