Signal encoding for aluminum alloy containers
This disclosure relates to advanced image signal processing technology including encoded signals and digital watermarking. One claim is directed to a container comprising: a 3004 or 3003 aluminum alloy shell, the 3004 or 3003 aluminum alloy shell comprising an outer surface and an inner surface; a 5182 aluminum alloy lid attached to the 3004 or 3003 aluminum alloy shell; and an opaque ink printed on the outer surface in a 2-dimensional pattern according to a machine-readable signal. The outer surface and the opaque ink printed on the outer surface comprise a spectral reflectance difference at a machine-vision wavelength in a range of 8%-30%, and the machine-readable signal is detectable from imagery representing the opaque ink printed on the outer surface. Of course, other containers, technology, methods, packages, objects, systems and apparatus are described in this disclosure.
1. A container comprising:
a 3004 or 3003 aluminum alloy shell, the 3004 or 3003 aluminum alloy shell comprising an outer surface and an inner surface;
a transparent ink printed on the outer surface in a first region, in which the transparent ink is printed to include a plurality of holes without any of the transparent ink printed therein;
an opaque ink printed within the plurality of holes on the outer surface within the first region,
in which the transparent ink printed on the outer surface and the opaque ink printed within the plurality of holes on the outer surface comprise a spectral reflectance difference at a machine-vision wavelength in a range of 8%-45%, and
in which the plurality of holes are arranged in a 2-dimensional pattern according to a machine-readable signal, the 2-dimensional pattern being machine-readable from imagery captured of the first region.
2. The container of claim 1 in which the range comprises 12-35%.
3. The container of claim 2 in which the range comprises 20-30%.
4. The container of claim 1 in which the transparent ink comprises transparent PMS® 185.
5. The container of claim 4 in which the opaque ink comprises opaque PMS® 185.
6. The container of claim 1 in which the plurality of holes each comprise a 2×2 pixel area at 600 dpi.
7. The container of claim 1 in which the plurality of holes each comprise a 3×3 pixel area at 600 dpi.
8. The container of claim 1 in which the plurality of holes each comprise a 4×4 pixel area at 600 dpi.
9. The container of claim 1 in which the plurality of holes each comprise a 1-pixel×1-pixel diagonal at 600 dpi.
10. The container of claim 1 in which the opaque ink comprises a trap printed over the transparent ink.
11. The container of claim 1 in which the transparent ink comprises a trap printed over the opaque ink.
12. The container of claim 10 in which the trap comprises a 1/600″ overprint at 600 dpi.
13. The container of claim 10 in which the trap comprises a 1/300″ overprint at 300 dpi.
14. The container of claim 10 in which the opaque ink comprises a reverse trap relative to the transparent ink.
15. The container of claim 10 in which the transparent ink comprises a reverse trap relative to the opaque ink.
16. The container of claim 14 in which the reverse trap comprises a 1/600″ underprint at 600 dpi.
17. The container of claim 14 in which the reverse trap comprises a 1/300″ underprint at 300 dpi.
18. The container of claim 13 further comprising a 5182 aluminum alloy lid attached to the outer surface of the 3004 or 3003 aluminum alloy shell.
19. The container of claim 1 in which the machine-readable signal comprises a sparse mark signal.
20. A container comprising:
a 3004 or 3003 aluminum alloy shell, the 3004 or 3003 aluminum alloy shell comprising an outer surface and an inner surface;
a 5182 aluminum alloy lid attached to the the outer surface of the 3004 or 3003 aluminum alloy shell; and
an opaque ink printed on the outer surface in a 2-dimensional pattern according to a machine-readable signal,
in which the outer surface and the opaque ink printed on the outer surface comprise a spectral reflectance difference at a machine-vision wavelength in a range of 8%-30%, and
in which the machine-readable signal is detectable from imagery representing the opaque ink printed on the outer surface.
21. The container of claim 20 in which the range comprises 12-25%.
22. The container of claim 20 in which the opaque ink comprises opaque PMS® 423.
23. The container of claim 20 in which each element of the opaque ink printed on the outer surface comprises a 2×2 pixel area at 600 dpi.
24. The container of claim 20 in which each element of the opaque ink printed on the outer surface comprises a 3×3 pixel area at 600 dpi.
25. The container of claim 20 in which each element of the opaque ink printed on the outer surface comprises a 4×4 pixel area at 600 dpi.
26. The container of claim 20 in which each element of the opaque ink printed on the outer surface comprises a 1-pixel×1-pixel diagonal at 600 dpi.
27. The container of claim 20 in which the machine-vision wavelength comprises a wavelength in a range of 660 nm-680 nm.
28. The container of claim 20 in which the machine-readable signal comprises a sparse mark signal.