Abstract: In image data retrieval, image data that becomes the base of search is specified. When the search is to be carried out according to the distance from the image data on an image map, an automatic setting process of retrieval information is carried out. Here, a keyword, icon, chromaticity and the like of that image data are automatically set as retrieval information. The position of that image data on the image map becomes the center of a range when the ambiguity is set. By setting the ambiguity of the image map, keyword, icon, chromaticity, and the like in this state, the range of ambiguity is displayed, and image data within that range is automatically retrieved. As a result, analogous image data can be searched for according to subtle and ambiguous information or information that cannot be quantified.