IMAGE COMPOSITING APPARATUS, IMAGE COMPOSITING METHOD, IMAGE COMPOSITING PROGRAM, AND RECORDING MEDIUM

A device is provided that generates a composite image using a first image and a second image having different exposure conditions. The device includes an image input unit, a likelihood calculating unit, an exposure estimating unit, and a compositing unit. The image input unit inputs the first image and the second image. The likelihood calculating unit calculates a subject motion likelihood at each pixel based on a difference between the first image and the second image. The exposure estimating unit estimates an exposure transform function that conforms the exposure conditions of the first image and the second image to each other based on the subject motion likelihood. The compositing unit composites the first image and the second image by using the exposure transform function.