An image generating device includes a background image acquirer that acquires an image of a background on which an image of an object is to be superimposed, a color extractor that extracts a color about one or a plurality of places in the image of the background, and a light source decider that decides the color of light output by a light source that illuminates the object based on the color extracted about the one or plurality of places. The image generating device further includes a drawing section that draws the image of the object based on the decided color of the light of the light source and an output image generator that generates an output image obtained by superimposing the image of the object on the image of the background.