IMAGE COMBINING APPARATUS, IMAGE COMBINING METHOD AND PROGRAM PRODUCT

A plurality of image data different in exposure condition are separated into a plurality of luminance component image data and a plurality of color-difference component image data, and the luminance component image data and the color-difference component image data are inputted to an image combining portion 11. A luminance component combining section 21 averages and smoothes the plurality of image data different in exposure condition and sets combining rates of the plurality of image data different in exposure condition by using the smoothed average luminance component image data. The separated plurality of luminance component image data are combined by using the set combining rates with respect to each attention pixel. On the other hand, a color-difference component combining portion 22 combines the separated plurality of color-difference component image data by using the combining rates used in the luminance component combining section 21.