IMAGE FORMING APPARATUS HAVING A SPECIMEN IMAGE JUDGING SECTION AND AN IMAGE INFORMATION SUITABILITY JUDGING SECTION

In the present image forming system, when a digital copying machine having no specimen image judging section makes a copy, it transfers an input image to an image processing apparatus having the specimen image judging section within the system to request to judge whether the input image is a copy-prohibited image on its behalf. When the judging result is returned within a predetermined period, the digital copying machine controls the copying operation based on the judging result: when the judging result is negative, a normal copying operation is carried out; when the copying is totally prohibited, the image processing apparatus ends the copying operation after informing the user that the copying operation is terminated because the copying of the subject image is prohibited. Consequently, whether the subject image data are a specimen image like paper money can be discovered at the image processing machine, thereby preventing a crime, such as forgery of paper money or securities. Also, if the specimen image judging section is installed in the image processing apparatus, each digital copying machine connected to the same does not have to include the specimen image judging section, thereby suppressing a cost increase.