Method for dynamic printing process calibration

Patent metadata

Field	Value
Publication number	US-9626604-B2
Application number	US-201514817541-A
Country	US
Kind code	B2
Filing date	Aug 4, 2015
Priority date	Aug 4, 2014
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

A method for the dynamic printing process calibration of a printing press includes determining a calibration dataset for the colored halftones of the process colors, determining a calibration dataset for the gray halftones of the process colors, determining a weighting factor for the two calibration datasets as a function of the original print and calculating a combined calibration dataset from the two determined calibration datasets, with reference to the weighting factor. The calculated combined calibration dataset is applied to the calibration of the printing process of a printing press.

First claim

The invention claimed is:

1. A method for a dynamic printing process calibration of a printing press, the method comprising the following steps:
determining a calibration dataset for colored halftones of process colors;
determining a calibration dataset for gray halftones of the process colors;
determining a weighting factor for the two calibration datasets as a function of an original print;
calculating a combined calibration dataset from the two determined calibration datasets, with reference to the weighting factor; and
applying the calculated combined calibration dataset to the calibration of the printing process of a printing press.

2. The method according to claim 1 , which further comprises carrying out the determination of the calibration dataset for the colored halftones of the process colors by measuring and evaluating at least one control element having colored halftones and adapting the halftones of the process colors while incorporating measured results and a set of characterization data describing the printing process.

3. The method according to claim 1 , which further comprises carrying out the determination of the calibration dataset for the gray halftones of the process colors by measuring and evaluating at least one gray value control element and adapting the gray values of the process colors while incorporating measured results and a set of characterization data describing the printing process.

4. The method according to claim 1 , which further comprises determining the weighting factor by using an automatic analysis of image content of the original print.

5. The method according to claim 1 , which further comprises defining the weighting factor manually by a user.

6. The method according to claim 1 , wherein the weighting factor includes different values with a continuous transition for different halftone areas, depending on an image content of the original print.

7. The method according to claim 1 , which further comprises:
creating a third calibration dataset from multidimensional transformation tables, in addition to the calibration datasets for the colored and gray halftones of the process colors;
including a weighting factor from the third calibration dataset; and
calculating a combined calibration dataset from all three present calibration datasets.

Assignees

• Heidelberger Druckmasch Ag

Inventors

• Bestmann Guenter

Classifications

• G06K15/1878

  Adjusting colours (image colour correction or control for documents in general H04N1/60) · CPC title

• B41F33/0045 Primary

  for automatically regulating the ink supply · CPC title

• G06K15/027 Primary

  Test patterns and calibration (arrangements for controlling or analysing printing mechanisms of typewriters or selective printing units B41J29/393 takes precedence; colour correction using test pattern analysis in general H04N1/6033) · CPC title

• B41P2233/10

  Starting-up the machine · CPC title

• G06K15/1881

  Halftoning (halftoning of still images in general H04N1/405, H04N1/52) · CPC title