Digital watermarking and data hiding with narrow-band absorption materials
The present disclosure relates to signal processing such as image processing, signal encoding, digital watermarking and data hiding. A sparse or dense digital watermark signal can be conveyed with a narrow-band absorption material corresponding to a center wavelength of a Point of Sale (POS) barcode scanner. The POS barcode scanner typically captures 2D imagery. Since the narrow-band absorption material absorbs over a narrow-band it is relatively imperceptible to the Human Visual System (HVS) but can be seen by the POS scanner.
1. A method comprising:
scanning a printed object with a red illumination scanner, the red illumination scanner having a wavelength at or around 660 nm, said scanning a printed object yielding scan data,
wherein the printed object includes a process color printed thereon through an offset or flexo printing press, the process color including a narrow-band absorption material that has a peak absorbance at or around 660 nm, the process color printed in a manner to convey redundant instances of an encoded plural-bit message, the encoded plural-bit message corresponding to a GTIN number;
analyzing the scan data with one or more programmed processors to decode the encoded plural-bit message, said analyzing yielding the GTIN number; and
providing the GTIN number as an output.
2. The method of claim 1 in which the process color comprises yellow, cyan or blue.
3. The method of claim 1 in which the encoded plural-bit message is conveyed with digital watermarking.
4. The method of claim 1 in which the narrow-band absorption additive emits fluorescence in the near infrared spectrum.
5. The method of claim 1 in which the scanner's wavelength at or around 660 nm comprises a wavelength including a peak located within a range comprising 640 nm to 680 nm.
6. The method of claim 5 in which the process color including a narrow-band absorption material includes a peak absorbance located within a range comprising 640 nm to 680 nm.
7. A printed object associated with a retail product, the printed object bearing both artwork and barcode markings, the barcode markings including plural barcodes, including two or more barcodes conveying the same payload, said two or more barcodes being printed on said packaging using an ink or additive with a spectral notch of 100 nm or less, which notch is centered at or around 660 nm.
8. The printed object of claim 7 in which said ink or additive comprises a spectral notch of 50 nm or less.
9. The printed object of claim 7 in which the printed object comprises product packaging.
10. The printed object of claim 7 in which the notch is centered within a range of 640 nm to 680 nm.
11. A system including:
a point of sale scanner including red illumination comprising a red LED illumination source including a wavelength centered at or around 660 nm, and
a printed object associated with a retail product, the printed object bearing both artwork and barcode markings, the barcode markings including plural barcodes, including two or more barcodes conveying the same payload, said two or more barcodes being printed on said packaging using an ink or additive with a spectral notch of 100 nm or less, which notch is centered at or around 660 nm.
12. The system of claim 11 in which the point of sale scanner includes a 2D camera for capturing imagery illuminated by the red LED illumination source.
13. The system of claim 11 in which the wavelength centered at or around 660 nm comprises a wavelength centered within a range of 640 nm to 680 nm.
14. A non-transitory computer readable medium comprising instructions stored thereon that, when executed by one or more processors, cause the one or more processor to perform the following acts:
controlling scanning of a printed object with a red illumination scanner, the red illumination scanner having a wavelength at or around 660 nm, said scanning a printed object yielding scan data, wherein the printed object includes a process color printed thereon through an offset or flexo printing press, the process color including a narrow-band absorption material that has a peak absorbance at or around 660 nm, the process color printed in a manner to convey redundant instances of an encoded plural-bit message, the encoded plural-bit message corresponding to a GTIN number;
analyzing the scan data to decode the encoded plural-bit message, said analyzing yielding the GTIN number; and
providing the GTIN number as an output.
15. The non-transitory computer readable medium of claim 14 in which the encoded plural-bit message is conveyed with digital watermarking.
16. The non-transitory computer readable medium of claim 14 in which the narrow-band absorption additive emits fluorescence in the near infrared spectrum.
17. The non-transitory computer readable medium of claim 14 in which the scanner's wavelength at or around 660 nm comprises a wavelength including a peak located within a range comprising 640 nm to 680 nm.
18. The non-transitory computer readable medium of claim 17 in which the process color including a narrow-band absorption material includes a peak absorbance located within a range comprising 640 nm to 680 nm.