1. An image processing apparatus comprising: digitizing means for digitizing image data; process means for dispersing an error, generated at the digitizing by said digitizing means, in an area around the image data; and discrimination means for discriminating whether the image data corresponds to an edge area or a non-edge area, wherein said process means is adapted to enlarge the area for error dispersion in a case of processing the image data of the non-edge area, as compared with a case of processing the image data of the edge area.