An accurate white balance adjustment process is provided for an image captured in an environment where different color components, such as an ambient light and a flash light are mixed. With respect to image to be captured under a plurality of different types of irradiation light, such as ambient light, and flash light, the image is captured or generated in an environment of single light irradiation. The white balance adjustment according to the parameter set up based on the color component (color temperature) of each type of irradiation light is carried out with respect to the image in each environment of the single light irradiation, so as to synthesize them Furthermore, with respect to the moved portion of the subject itself, the present invention is arranged such that the pixel value is compensated and set up based on adjacent pixel values of the motionless portion, it becomes possible to generate a natural image data with smooth changes between pixels.