Patent US 7,072,074

An image processing apparatus inputs photographic image data containing dot-matrix pixels and converts the input pixels according to predetermined correspondence relationship information, so as to produce processed image data. A correspondence relationship holding unit of the apparatus holds correspondence relationship information, including a plurality of correspondence relationships, for the conversion, and applicable object information. The applicable object information, includes, for each correspondence relationship, a respective condition. A correspondence relationship judging unit judges, for each of the input pixels, indicating whether a given pixel meets the condition of any of the correspondence relationships. An image data converting unit performs a conversion operation on the pixels of the input image data to produce processed image data. For each pixel, however, the conversion operation is performed using only the correspondence relationships indicated by the judgments of the correspondence relationship judging unit.