A retrieving key representing position information is used to retrieve image information containing the retrieving key information at a high speed and high precision. First a retrieving key is inputted to display retrieval information. The retrieving key is used to retrieve an image having a large size relative to a geometric distortion error, and the longitude/latitude conversion coefficients of the retrieved image are corrected. By using the corrected longitude/latitude conversion coefficients, an image having a small size relative to the geometric distortion error is retrieved, and the retrieved image is subject to distortion correction and image magnification.