Patent ID: 11930147
Assignee: SOTEC CONSULTING S.L.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H  B | IPC B  H

Claim 15:
16. The system according claim 9, further comprising:
a database;
a digital watermark embedding device, configured for:
inserting a digital watermark into a digital document, wherein the digital watermark comprises at least one encoded mark identifier;
storing the mark identifier in the database;
a printer configured for printing the marked digital document, obtaining at least one printed document for calibration;
calibration equipment configured for:
carrying out a calibration scan of the at least one printed document for calibration;
limiting the maximum marking frequency values obtained in the calibration scan to obtain a calibration threshold;
storing the calibration threshold in the database, associating it with the corresponding mark identifier thereof.