Even a mosaic image in an uncompleted state, it makes a mosaic image having high recognizability of a picture of an original image displayed. An image providing device includes an image acquisition means that acquires an image specified by a user, a candidate determination means that, on the basis of color information of the acquired image and color information of the regions, determines regions to be candidates for a region to which the acquired image is assigned, an edge degree acquisition means that acquires edge degrees indicating degrees of edges in the regions determined as the candidates, an assignment determination means that, on the basis of the acquired edge degrees, determines a region to which the acquired image is assigned from the regions determined as the candidates, and a presentation means that, on the basis of assignment determined by the assignment determination means, causes a mosaic image in which the acquired image is placed to be presented.