Methods and systems for ensuring correct printing plate usage and signal tolerances
Advanced signal processing technology including signal encoding and digital watermarking. Disclosure includes monitoring spectral differences within control strip area to determine signal robustness of encoded signals printed outside of control strip area. Other combinations and technology provided too.
1. A method of monitoring a spectral difference between a substrate and one or more colors, the one or more colors configured to carry an encoded signal, said method comprising:
determining a minimum ink value and a maximum ink value of an encoded signal carrier;
determining a spectral reflectance difference at or around 660 nm between: i) the substrate without any ink and the minimum ink value, and ii) the substrate without any ink and the maximum ink value;
based on the difference of i and ii, determining a tolerance range;
printing the minimum ink value and the maximum ink value in a control strip area;
measuring the spectral reflectance of the substrate, the printed minimum ink and the printed maximum ink to yield measurements, and using the measurements to determine whether the printing press is maintaining printing within the determining tolerance range.
2. The method of claim 1 in which the encoded signal comprises digital watermarking.
3. The method of claim 1 in which the determined tolerance range corresponds to encoded signal robustness.
4. The method of claim 1 in which the encoded signal comprises a Global Trade Item Number (GTIN).
5. The method of claim 1 in which the substrate comprises a verification icon printed adjacent to the control strip, the verification icon comprising a plurality of elements that collectively convey information to determine whether expected printing plates are used in a press run.
6. A method of monitoring a spectral difference to determine signal robustness of an encoded signal, said method comprising:
measuring, from a printed control strip area on a press sheet, first spectral reflectance corresponding to a first ink printed on the press sheet and second spectral reflectance corresponding to a second ink printed on the press sheet, said measuring yielding measurements, in which the first ink comprises a first signal carrier of an encoded signal and the second ink comprises a second signal carrier of the encoded signal, in which the encoded signal is printed on the press sheet outside of the printed control strip area, and in which the encoded signal comprises a plural-bit message detectable from imagery representing an area of the press sheet outside of the printed control strip area;
determining a spectral reflectance difference at or around 660 nm from within the printed control strip area on the press sheet between: i) the first spectral reflectance, and ii) the second spectral reflectance; and
based on the difference of i and ii, determining whether the encoded signal printed on the press sheet outside of the printed control strip area achieves a target signal robustness.
7. The method of claim 6 in which said measuring is performed by a system comprising an in-line to press sheet spectrophotometer.
8. The method of claim 6 in which said measuring utilizes a spectrophotometer.
9. The method of claim 6 further comprising issuing an alert when said determining whether the encoded signal printed outside of the control strip area on the press sheet achieves a target signal robustness determines that the target signal robustness is not achieved.
10. The method of claim 9 in which one or more multi-core processors are configured to perform said determining a spectral reflectance difference at or around 660 nm between: i) the first spectral reflectance, and ii) the second spectral reflectance; and
based on the difference of i and ii, said determining whether the encoded signal printed outside of the control strip area on the press sheet achieves a target signal robustness.
11. The method of claim 6 in which the first ink comprises a maximum value of a process color ink or a spot color ink and the second ink comprises a reduced intensity percentage of the process color ink or the spot color ink.
12. The method of claim 6 in which the first ink and the second ink comprise the same process color or spot color ink, but at different intensity percentages.
13. The method of claim 6 in which the encoded signal comprises digital watermarking.
14. The method of claim 6 in which the encoded signal comprises a Global Trade Item Number (GTIN).
15. A method of monitoring a spectral difference, said method comprising:
measuring, from a printed control strip area on a press sheet, first spectral reflectance corresponding to a first ink printed on the press sheet and second spectral reflectance corresponding to a second ink printed on the press sheet, said measuring yielding measurements, in which the first ink comprises a first signal carrier of an encoded signal and the second ink comprises a second signal carrier of the encoded signal;
determining a spectral reflectance difference at or around 660 nm between: i) the first spectral reflectance, and ii) the second spectral reflectance;
based on the difference of i and ii, determining whether the encoded signal printed on the press sheet achieves a target signal robustness,
in which the press sheet comprises a verification icon printed adjacent to the control strip, the verification icon comprising a plurality of elements that collectively convey information to determine whether expected printing plates are used in a press run.
16. An electronic device comprising:
memory storing spectral reflectance measurements corresponding to a printed control strip area on a press sheet, the spectral reflectance measurements comprising a first spectral reflectance measurement corresponding to a first ink printed on the press sheet, and a second spectral reflectance measurement corresponding to a second ink printed on the press sheet, in which the first ink comprises a first signal carrier of an encoded signal and the second ink comprises a second signal carrier of the encoded signal, in which the encoded signal is printed on the press sheet outside of the printed control strip area, and in which the encoded signal comprises a plural-bit message detectable from imagery representing an area of the press sheet outside of the printed control strip area;
one or more multi-core processors configured for:
determining a spectral reflectance difference at or around 660 nm from the printed control strip area on the press sheet between: i) the first spectral reflectance, and ii) the second spectral reflectance; and
based on the difference of i and ii, determining whether the encoded signal printed on the press sheet outside of the printed control strip area achieves a target signal robustness.
17. The electronic device of claim 16 in which the spectral reflectance measurements are obtained from a system comprising an in-line to press sheet spectrophotometer.
18. The electronic device of claim 16 in which said spectral reflectance measurements are obtained from a spectrophotometer.
19. The electronic device of claim 16 further comprising issuing an alert when said determining whether the encoded signal printed outside of the control strip area on the press sheet achieves a target signal robustness determines that the target signal robustness is not achieved.
20. The electronic device of claim 16 in which the first ink comprises a maximum value of a process color ink or a spot color ink and the second ink comprises a reduced intensity percentage of the process color ink or the spot color ink.
21. The electronic device of claim 16 in which the first ink and the second ink comprise the same process color or spot color ink, but with different intensity percentages.
22. The electronic device of claim 16 in which the encoded signal comprises digital watermarking.
23. The electronic device of claim 16 in which the encoded signal comprises a Global Trade Item Number (GTIN).
24. An electronic device comprising:
memory storing spectral reflectance measurements corresponding to a printed control strip area on a press sheet, the spectral reflectance measurements comprising a first spectral reflectance measurement corresponding to a first ink printed on the press sheet, and a second spectral reflectance measurement corresponding to a second ink printed on the press sheet, in which the first ink comprises a first signal carrier of an encoded signal and the second ink comprises a second signal carrier of the encoded signal;
one or more multi-core processors configured for:
determining a spectral reflectance difference at or around 660 nm between: i) the first spectral reflectance, and ii) the second spectral reflectance; and
based on the difference of i and ii, determining whether the encoded signal printed on the press sheet achieves a target signal robustness,
in which the press sheet comprises a verification icon printed adjacent to the control strip, the verification icon comprising a plurality of elements that collectively convey information to determine whether expected printing plates are used in a press run.