Abstract: A method is disclosed that relates to maintaining or improving the end quality of the visual color imprint of multiple-colored patterned surfaces. These surfaces cannot be measured using the decorations that are manufactured by printing processes, the so-called primary decoration, because subsequent processes change the color imprint further resulting in the so-called secondary color imprint. According to the invention, prediction rules are determined based on samples from the primary and secondary decorations during a learning phase to establish from n-channel images of samples of the primary decoration color imprint characteristics and convert those to such characteristics for the secondary decoration; and/or to establish from n-channel images of samples of the primary decoration images of the secondary decoration and to calculate color imprint characteristics.

Abstract: A method and arrangement that automatically verify a visually perceived color impression of multicolor color images in a printed product having text in addition to color images includes digitally storing a reference image in a database for each multicolor color image to be verified, scanning the printed product uses an imaging sensor, and converts the signal obtained into a digital image file. The digital image file is broken down into regions containing text or graphics and into regions of color images without text or graphics. A statistical descriptive feature of colors occurring and a measure of image sharpness are calculated for each region consisting of a multicolor color image, and are then compared with stored data for the reference image. Deviation rates for the statistical descriptive feature of the colors occurring and for the measure of the image sharpness are calculated and displayed.

Abstract: A document-examining apparatus is provided for automatically examining the authenticity elements of secured documents. It includes a compound slide which can be moved in the X and Y directions and on which the components required to evaluate the distinguishing authenticity features are mounted. The X slide of the compound slide is mounted on a Y slide. A first group of evaluating units for evaluating diffraction elements on a document is disposed on the X slide. A second group of evaluating components, for example, for evaluating text, an IR field and/or a photographic field, may be mounted on the Y slide. In addition, a source of UV radiation may be provided for examining distinguishing fluorescence features of a document, the fluorescence being evaluated by a stationary evaluating unit or by the evaluating unit on the X slide.

Abstract: An apparatus for evaluating distinguishing authenticity features comprising diffraction elements on a document which is illuminated by an illumination source. The distinguishing authenticity element which is to be examined, diffracts the beam of the illuminating source and projects it onto an evaluating unit in the device. In order to be independent of the nature and location of the diffraction pattern, the diffraction pattern derived from the document to be examined is projected onto a screen and the image of the pattern recorded and evaluated by a camera (matrix or cells).