Abstract: The quality of printed matter, which is one of several copies of the same printed matter produced by a printing machine, is evaluated. An amount of copies of the printed matter is selected from the total production of this printed matter. The selected amount of these copies are evaluated with regard to at least one error type which belongs to an amount of different error types or with regard to at least one feature of the error. Within the selected amount of copies, an error of a defined error type or of a defined feature, which is detected on at least one of the copies, is evaluated in relation to at least one error of another type or feature detected on the same copy, or another copy of the selected amount. The printed matter is classified as having good or bad quality based on that evaluation. A common reading, producing image data, is obtained by an image sensor from the selected copies.

Abstract: A method is used for the early identification of a deviation in the printed images which have been formed by a printing press during continuous production. A second decision threshold is provided, in addition to a decision regarding good or bad print quality. A current printed image, that has been captured, is compared with a reference image. If the current image deviates from the reference image, that deviation is evaluated using two decision thresholds.

Abstract: A printing machine has at least one machine element which can be adjusted by the use of a setting element. An adjustment of the one machine element has an effect on the quality of the printing performed by the printing machine. An optical detection device, which includes a sensor that is oriented toward the surface of a material which is being printed, detects the quality of the printing. A controlling device receives data from the optical sensor and adjusts, together with the setting element, the at least one machine element based on a difference between a quality of the printing which has been specified as a set value and the quality of the printing detected as an actual value by the optical detection device. This adjustment is done to manage the differences between the set value and the actual value.

Abstract: A material, with at least one identification characteristic, is subjected to a qualitative evaluation. A color image of this at least one identification characteristic is taken using an electronic image sensor which produces an electrical signal that is evaluated by an evaluation device. Another electrical signal is obtained from at least one reference image and is stored in a data memory. The second electric signal, has a set point value, for the first electric signal, for at least two set point values contained in the reference image. The first signal is compared to at least two set point values in the second image. The color image of the identification characteristic is tested for deviation from the reference. The identification characteristic is checked for association with at least one aspect of the identification characteristic of the material. The tasks are carried out in a continuous working process being carried out by a machine, such as a printing machine, during a continuous printing process.

Abstract: An electronic image sensor is used for evaluating an image. Several individual sensors, each of which is provided with several pixels, are utilized in the electronic image sensor. The pixels of at least one individual electronic image sensor are read out only in part. Individual image sectors are thus effectively masked to reduce the amount of image data to be processed.