To accurately judge the propriety of an image or the like without necessity to register characters or the like being an examination reference from an image pickup device or the like one by one as an image.

A prescribed reference character database (such as a set of standard character font) is previously stored on a ROM. When starting an examination, a character code to become an examination target is inputted from an external device such as a keyboard and stored on a RAM or the like as registered character data. The image pickup device photographs image information to become the examination target and fetches it as an examination image (step S21). In respect to this examination image, character information in the reference character database is retrieved, the similarity of character data is calculated (step S23), and the plural character candidates of high similarity are extracted together with the similarity and sorted in the order from the highest similarity (step S24). The character candidate of the highest similarity (the character candidate of first ranking) is compared with previously registered character data, and when the both are matched, it is judged the examined image is satisfactory (step S25).