Predicting detectability and grading prior to printing

• US 10,382,645 B2
• Filed: 03/12/2018
• Issued: 08/13/2019
• Est. Priority Date: 03/10/2017
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Bai, Yang, Chadwick, Dean H., Bennett, Jackson B., Pinard, Daniel T.
• Primary Examiner(s): Safaipour, Houshang
• Application Number:
  US15/918,924
• Publication Number:
  US 20180352111A1
• Time in Patent Office: 519 Days
• Field of Search: 358 19
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 2201/0202 whereby the quality of watermarked images is measured; Measuring quality or performance of watermarking methods; Balancing between quality and robustness
• CPC Class Codes: H04N 1/32251 in multilevel data, e.g. greyscale or continuous tone data
• CPC Class Codes: H04N 1/32309 in colour image data
• CPC Class Codes: H04N 1/6008 with primary colour signals, e.g. RGB or CMY(K)

Abstract

The present disclosure relates generally to image signal processing, including encoding signals for image data or artwork. A color blend/print model is used to predict signal detectability and visibility as is printed on a particular substrate, which facilitates object grading prior to print runs.

Claims

1. An image processing system comprising:

an input to receive a design file, the design file comprising an encoded signal carrying a plural-bit identifier, the design file comprising a design including an area of layered colors;

a blend module for operating on the design file, the blend module generating reflectance spectra estimates for the design including for the area of layered colors, the reflectance spectra estimates provided on a per pixel basis for the design;

an image warping module for transforming a grayscale representation generated from the reflectance spectra estimates at or around 660 nm, the image warping module transforming the design according to an object form factor;

a signal strength module for producing a representation of encoded signal detectability, the signal strength module operating on a transformed version of the grayscale image representation generated from the reflectance spectra estimates at or around 660 nm; and

a visibility module for generating a visibility map of a color image representation generated from a weighted sum of the reflectance spectra estimates.

2. The image processing system of claim 1 further comprising an output for outputting the representation of the encoded signal detectability.

3. The image processing system of claim 2 in which the representation of the encoded signal detectability comprises a heat map overlay on the color image representation generated from a weighted sum of the reflectance spectra estimates.

4. The image processing system of claim 1 further comprising a signal encoder which generates an encoded design.

5. The image processing system of claim 4 in which the signal encoder comprises a digital watermark encoder.

6. The image processing system of claim 1 in which the object form factor comprises a cylinder or trapezoid.

7. An image processing method comprising:

receiving a digital design comprising an encoded signal carrying a plural-bit identifier, the digital design including an area of layered colors to be printed on a substrate;

generating reflectance spectra estimates for the digital design including for the area of layered colors as if printed on the substrate, the reflectance spectra estimates provided on a per pixel basis for the digital design;

generating a grayscale image representation of the digital design from the reflectance spectra estimates at or around 660 nm;

transforming the grayscale image representation according to an object form factor, said transforming yielding a transformed grayscale image;

generating a representation of encoded signal detectability from the transformed grayscale image;

producing a visibility map of a color image representation of the digital design generated from a weighted sum of reflectance spectra estimates on a per pixel basis; and

providing the representation of encoded signal detectability and the visibility map to influence signal encoding.

8. The image processing method of claim 7 in which the signal encoding comprises digital watermarking.

12. The image processing method of claim 7 further comprising outputting the representation of the encoded signal detectability.

13. The image processing method of claim 12 in which the representation of the encoded signal detectability comprises a heat map overlay on the color image representation generated from a weighted sum of the reflectance spectra estimates.

14. The image processing method of claim 7 further comprising encoding the digital design according to the representation of encoded signal detectability and the visibility map.

15. The image processing method of claim 14 in which the encoding comprises digital watermarking.

16. The image processing method of claim 7 in which the object form factor comprises a cylinder or trapezoid.

9. A method of generating a detection grade for a 3D object comprising plural panels, comprising:

receiving a digital design comprising an encoded signal carrying a plural-bit identifier, the digital design including an area of layered colors to be printed on a substrate;

generating reflectance spectra estimates with a color blend model for the digital design including for the area of layered colors as if printed on the substrate, the reflectance spectra estimates provided on a per pixel basis for the digital design;

generating a grayscale image representation of the digital design from the reflectance spectra estimates, using modeling of an illumination source with a peak illumination occurring in a spectral range between 630 nm to 710 nm;

transforming the grayscale image representation according to an object form factor, said transforming yielding a transformed grayscale image;

defining plural pairs of adjoining panels;

determining an encoded signal detectability grade for each of the pairs of adjoining panels from the transformed grayscale image; and

combining the grades to yield a net detection grade for the 3D object.

10. The method of claim 9 in which the digital design comprises artwork for later printing on a flat substrate, the printed flat substrate to be later folded to define the 3D object, wherein the artwork includes six rectangular portions, corresponding to six panels of the 3D object, said method further comprising:

establishing x- and y-coordinates for six points in the digital design; and

from the six points, determining twenty-four different ordered pairs of object panels that may be respectively presented to first and second faces of a bioptic scanner.

11. The method of claim 10 in which said establishing x- and y-coordinates includes:

establishing x- and y-coordinates for two opposing corners of one of the six rectangular portions; and

establishing x- and y-coordinates for two opposing corners of another of the six rectangular portions.

17. A non-transitory computer readable medium comprising instructions stored therein that, when executed by one or more processors, cause the one or more processors to perform the following acts:

receiving a digital design comprising an encoded signal carrying a plural-bit identifier, the digital design including an area of layered colors to be printed on a substrate;

generating reflectance spectra estimates for the digital design including for the area of layered colors as if printed on the substrate, the reflectance spectra estimates provided on a per pixel basis for the digital design;

generating a grayscale image representation of the digital design from the reflectance spectra estimates at or around 660 nm;

transforming the grayscale image representation according to an object form factor, said transforming yielding a transformed grayscale image;

generating a representation of encoded signal detectability from the transformed grayscale image;

producing a visibility map of a color image representation of the digital design generated from a weighted sum of reflectance spectra estimates on a per pixel basis; and

providing the representation of encoded signal detectability and the visibility map to influence signal encoding.

18. The non-transitory computer readable medium of claim 17 further comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform the following act:

outputting the representation of the encoded signal detectability.

19. The non-transitory computer readable medium of claim 18 in which the representation of the encoded signal detectability comprises a heat map overlay on the color image representation generated from a weighted sum of the reflectance spectra estimates.

20. The non-transitory computer readable medium of claim 17 further comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform the following act:

encoding the digital design according to the representation of encoded signal detectability and the visibility map.

21. The non-transitory computer readable medium of claim 20 in which the encoding comprises digital watermarking.

22. The non-transitory computer readable medium of claim 17 in which the object form factor comprises a cylinder or trapezoid.

23. An image processing system for generating a detection grade for a 3D object comprising plural panels, said image processing system comprising:

an input to receive a digital design comprising an encoded signal carrying a plural-bit identifier, the digital design including an area of layered colors to be printed on a substrate;

one or more multi-core processors programmed for;

generating reflectance spectra estimates with a color blend model for the digital design including for the area of layered colors as if printed on the substrate, the reflectance spectra estimates provided on a per pixel basis for the digital design;

generating a grayscale image representation of the digital design from the reflectance spectra estimates, using modeling of an illumination source with a peak illumination occurring in a spectral range between 630 nm to 710 nm;

transforming the grayscale image representation according to an object form factor, said transforming yielding a transformed grayscale image;

defining plural pairs of adjoining panels;

determining an encoded signal detectability grade for each of the pairs of adjoining panels from the transformed grayscale image; and

combining the grades to yield a net detection grade for the 3D object.

24. The image processing system of claim 23 in which the digital design comprises artwork for later printing on a flat substrate, the printed flat substrate to be later folded to define the 3D object, wherein the artwork includes six rectangular portions, corresponding to six panels of the 3D object, in which said one or more multi-core processors are programmed for:

establishing x- and y-coordinates for six points in the digital design; and

from the six points, determining twenty-four different ordered pairs of object panels that may be respectively presented to first and second faces of a bioptic scanner.

25. The image processing system of claim 24 in which said establishing x- and y-coordinates includes:

establishing x- and y-coordinates for two opposing corners of one of the six rectangular portions; and

establishing x- and y-coordinates for two opposing corners of another of the six rectangular portions.

26. A non-transitory computer readable medium comprising instructions stored therein that, when executed by one or more processors, cause the one or more processors to perform the following acts:

receiving a digital design comprising an encoded signal carrying a plural-bit identifier, the digital design including an area of layered colors to be printed on a substrate;

generating reflectance spectra estimates with a color blend model for the digital design including for the area of layered colors as if printed on the substrate, the reflectance spectra estimates provided on a per pixel basis for the digital design;

generating a grayscale image representation of the digital design from the reflectance spectra estimates, using modeling of an illumination source with a peak illumination occurring in a spectral range between 630 nm to 710 nm;

transforming the grayscale image representation according to an object form factor, said transforming yielding a transformed grayscale image;

defining plural pairs of adjoining panels;

determining an encoded signal detectability grade for each of the pairs of adjoining panels from the transformed grayscale image; and

combining the grades to yield a net detection grade for a 3D object associated with the digital design.

27. The non-transitory computer readable medium of claim 26 in which the digital design comprises artwork for later printing on a flat substrate, the printed flat substrate to be later folded to define the 3D object, wherein the artwork includes six rectangular portions, corresponding to six panels of the 3D object, in which said instructions include:

establishing x- and y-coordinates for six points in the digital design; and

from the six points, determining twenty-four different ordered pairs of object panels that may be respectively presented to first and second faces of a bioptic scanner.

28. The non-transitory computer readable medium of claim 27 in which the establishing x- and y-coordinates includes:

establishing x- and y-coordinates for two opposing corners of one of the six rectangular portions; and

establishing x- and y-coordinates for two opposing corners of another of the six rectangular portions.