A target object texture mapping unit makes correspondence of image data of a measured target object to shape data. A reference object texture mapping unit makes correspondence of image data of a measured reference object to shape model of the reference object. A normal correspondence making unit compares normal data of the target object with normal data of the reference object and makes correspondence of the normals having the corresponding directions. A light source influence eliminating unit prepares target object light source influence-eliminated image data on the basis of the correspondence made by the normal correspondence making unit. A correction light source influence adding unit adds an influence of a light source to the target object light source influence-eliminated image data, thus preparing target object corrected image data.