When a place where a different panoramic image was captured is present in a direction in which a panoramic image to be displayed is captured, a marker setting unit associates a marker indicating that the different panoramic image is present in said image-captured direction with the panoramic image to be displayed. A mapping processing unit maps, as a texture, the panoramic image to be displayed, with which the marker of the different panoramic image is associated, in a three-dimensional panoramic space. A three-dimensional image generation unit generates a three-dimensional panoramic image when the three-dimensional panoramic space is viewed in a designated visual line direction, with a place where the panoramic image to be displayed is captured as a visual point position. A user interface unit accepts a user's instruction regarding the displayed three-dimensional panoramic image.