An image processing device includes a memory; and a processor coupled to the memory and configured to: acquire, for each of different entrance positions, each of captured images generated by changing the luminance of pixels within a given distance from an entrance position indicating a location at which light is incident to a photographic subject, the pixels being in an image obtained by illuminating the photographic subject with the light from a light source and capturing the light reflected from the photographic subject, generate a composite image by adding together each of the captured images, and generate an output image by performing image restoration on the composite image by using a model having the shape of the reflected light.