Including information signals in product packaging and other printer media
The present disclosure relates generally to data hiding for retail product packaging and other printed objects. One embodiment embeds an information signal in a spot color for product packaging. The spot color is screened, and overprinted with process color tint. The tint is modulated prior to overprinting with optimized signal tweaks. The optimization can include consideration of a detector spectral dependency (e.g., red and/or green illumination). Many other embodiments and combinations are described in the subject patent document.
1. A retail product package comprising:
a first printed area, the first printed area comprising a combination of i) data representing first color data (S1), and ii) data representing second color data (S2), in which encoded information is provided on said retail product package through modulation of the data representing second color data (S2) with max (positive) and min (negative) tweaks;
in which the combination has been optimized by:
determining a color error between data representing third color data (S3) and a combination of S1 and S2,
determining an information modulating error associated with the max and min tweaks; and
finalizing the combination of S1 and S2, including minimizing the color error and minimizing the information modulating error; and
a second printed area including a 1D or 2D barcode;
a third printed area including text information printed thereon.
2. The retail product packaging of claim 1 in which the combination has been optimized by a process which included determining color weights and a global signal strength, the color weights to be applied to the data representing second color data (S2) and the global signal strength for regulating the modulation.
3. The retail product packaging of claim 2 in which the combination has been optimized by a process constrained by spectral reflectance between 630 nm to 680 nm.
4. The retail product packaging of claim 2 in which combination has been optimized by a process constrained by spectral reflectance between 655 nm to 670 nm.
5. The retail product packaging of claim 2 in which the data representing second color data (S2) comprises data representing two or more process colors, and the data representing first color data (S1) represents a spot color.
6. The retail product packaging of claim 5 in which the spot color comprises a screened-back version of the third color data (S3).
7. The retail product packaging of claim 1 in which the max and min tweaks correspond to a 2-dimensional image digital watermark tile.
8. An image processing system for generating a design for a retail product package comprising:
memory storing data representing first color data (S1);
one or more multi-core processors configured for:
minimizing: i) a color match error between (S1) and a combination of data representing second color data (S2) and data representing third color data (S3), the combination including auxiliary encoded information in (S3), and ii) an information modulating error associated with modulations of (S3) that carry the auxiliary encoded information,
said minimizing being constrained by a spectral component associated with an anticipated information detector,
obtaining color percentage values associated with at least (S3) and a signal strength value for regulating the modulations; and
an output configured for outputting the color percentage values and a signal strength value.
9. The image processing system of claim 8 in which the spectral component comprises a metric associated with a spectral reflectance between 650 nm to 680 nm.
10. The image processing system of claim 8 in which the modulations correspond to a 2-dimensional image digital watermark tile.
11. The image processing system of claim 8 further comprising a display, in which said one or more multi-core processors are configured for providing a graphical user interface through which encoding options can be selected.
12. The image processing system of claim 8 in which the combination is optimized by determining color weights and a global signal strength, the color weights to be applied to the data representing third color data (S3) and the global signal strength for regulating the modulation.
13. An image processing apparatus comprising:
memory storing color data representing a spot color ink;
memory storing a table to obtain data representing a process color ink tint, the process color ink tint including at least a Cyan (C) component, a Magenta (M) component and a Yellow component (Y);
one or more multi-core processors configured for:
simulating an overprinting of the color data with the process ink tint;
decomposing the process ink tint into a maximum signal tweak and a minimum signal tweak, each of the maximum signal tweak and the minimum signal tweak having a Cyan (C) component, a Magenta (M) component and a Yellow component (Y);
minimizing a color error metric of the overprinting relative to the data representing the spot color ink;
optimizing the maximum signal tweak and the minimum signal tweak according to at least a spectral dependency, in which said optimizing comprises determining color weights and a global signal strength;
modulating the process color ink tint with the maximum signal tweak and the minimum signal tweak to represent an information signal, the color weights for application to the process color tint and the global signal strength;
outputting the modulated process color ink tint for overprinting with the color data.
14. The image processing apparatus of claim 13 in which the spectral component comprises a metric associated with a spectral reflectance between 650 nm to 680 nm.
15. The image processing apparatus of claim 13 in which the information signal corresponds to a 2-dimensional image digital watermark tile.
16. The image processing apparatus of claim 13 further comprising a display, in which said one or more multi-core processors are configured for providing a graphical user interface through which modulating options can be selected.
17. A system for transforming color data to include an information signal embedded therein, comprising:
memory storing spot color data, and system constraint information, the system constraint information including at least one spectral dependency; and
one or more multi-core processors configured to generate C (Cyan), M (Magenta), Y (Yellow) process color data, and to combine the generated process color data with the spot color data to yield a combination having a minimized color error approximation of the spot color data, the one or more multi-core processors configured to generate signal modulation values in terms of at least ΔC, ΔM, ΔY for modulating the C, M, Y process color data to carry the information signal, the modulation values optimized based on the at least one spectral dependency; and
one or more multi-core processors configured as an signal embedder that transforms the C, M, Y process color data with the signal modulation values.
18. The system of claim 17 in which the spot color data comprises a screen of spot color data.
19. The system of claim 17 in which the signal modulation values correspond to a 2-dimensional image digital watermark tile.
20. The system of claim 17 in which the at least one spectral dependency comprises a wavelength at 660 nm.
21. A method for generating a design for a printed article comprising:
minimizing: i) a color match error between a first color (S1) and data representing second color data (S2), the second color data (S2) including auxiliary encoded information, and ii) an information modulating error associated with modulations of the second color data (S2) that carry the auxiliary encoded information, said minimizing being constrained by a spectral component associated with an anticipated information detector, in which said minimizing yields color percentage values associated with at least the data representing second color data (S2) and a signal strength value for regulating the modulations; and outputting the color percentage values and a signal strength value for use in a design to be printed on the printed article.
22. The method of claim 21 in which the modulations correspond to a 2-dimensional image digital watermark tile.
23. The method of claim 21 in which the first color (S1) comprises a screened back version of a spot color.
24. The method of claim 21 in which the second color data (S2) comprises data representing Cyan (C), Magenta (M), and Yellow (Y).