Patent ID: 7969483

Claim:
A white balance control method of carrying out white balance control using a color signal of each of several blocks obtained by dividing an image signal equivalent to one frame in a screen, comprising: transforming a color space coordinate expressing the color signal of each divided block into a white balance determination space coordinate for determining a white balance in the screen; setting a light source estimation area for estimating a kind of a light source in the white balance control and a high-saturation determination area for determining whether or not the color signal of each block in the screen has high saturation, in a white balance determination space to which the transformed white balance determination space coordinate belongs; estimating the kind of the light source based on a white balance determination space coordinate distribution in the light source estimation area; determining a kind of the light source based on the estimated kind of the light source and a white balance determination space coordinate distribution in the high-saturation determination area; calculating a white balance control information based on the determined kind of the light source; carrying out white balance control with respect to the image signal based on the calculated white balance control information; determining whether or not an imaging apparatus including an imaging unit capturing the image signal is a lens detachable type; reading characteristic information of the imaging unit, characteristic information of a lens and characteristic information of each specific light source, which are previously stored, when it is determined that the imaging apparatus is a lens detachable type; calculating white balance control information of each specific light source based on the read characteristic information; and transforming the calculated white balance control information of each specific light source into the white balance determination space coordinate, wherein the light source estimation area and the high-saturation determination area are set to have an area overlapping each other, and the kind of the light source is determined based on the white balance determination space coordinate distribution in the light source estimation area, the white balance determination space coordinate distribution in the high-saturation determination area and a white balance determination space coordinate distribution in the area overlapping the light source estimation area with the high-saturation determination area, and wherein one or more light source estimation areas are set corresponding to a specific light source, while one or more high-saturation determination areas are set corresponding to hue, and each set light source estimation area has an area mutually overlapping with one or more high-saturation determination areas.