Patent ID: 8611613

Claim:
A method for checking print products of the same kind which are transported by a conveying device, comprising: recording test images in a teach-in phase at a plurality of points on the print product using a digital camera; defining an evaluation region within each test image, which evaluation region is smaller than, or equal to, a size of the test image; analyzing characteristic information of each evaluation region; selecting the test image, in which the evaluation region with a most distinctive characteristic information is located, as a reference image; and checking subsequent print products of the same kind by recording at least one check image at a position corresponding to the reference image and by image-data comparison of at least one subregion of the check image with the evaluation region of the reference image; wherein, for ascertaining the reference image, the evaluation region is divided into a plurality of subregions, which are evaluated in terms of their characteristic information; wherein, for checking subsequent print products, a comparison of characteristic information of the subregions of the evaluation region of the reference image with corresponding subregions of the check image is carried out; and wherein the comparison is carried out for a number of subregions by correlation methods and for a number of subregions by comparing gray-scale mean values.