Method and apparatus for encoding substrates with information

• US 7,427,334 B2
• Filed: 05/22/2006
• Issued: 09/23/2008
• Est. Priority Date: 11/10/1999
• Status: Expired due to Fees

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Alattar, Adnan M.
• Primary Examiner(s): HUG, ERIC J
• Application Number:
  US11/419,718
• Publication Number:
  US 20070110296A1
• Time in Patent Office: 855 Days
• Field of Search: 162/110, 162/116, 162/117, 162/140, 162/208, 162/210, 162/358.2, 162/358.4, 162/362, 162/373, 162/378, 162/348, 162/357, 382/135, 382/191, 382/108, 382/278, 382/280, 382/100, 382/276, 382/285, 283/113
• US Class Current: 162/110
• CPC Class Codes: D21F 11/00 Processes for making continuous lengths of paper, or of cardboard, or of wet web for fibre board production, on paper-making machines
• CPC Class Codes: D21F 9/00 Complete machines for making continuous webs of paper
• CPC Class Codes: G03G 21/046 by discriminating a special original, e.g. a bank note
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain

Abstract

The present invention provides methods and apparatus to encode substrates (e.g., paper, synthetics, etc.) with information. In one implementation a method is provided including: receiving data that corresponds to a two-dimensional signal that encodes plural bits of data; receiving data that corresponds to a frequency-domain signal, the data corresponding to a representation in a spatial domain through inverse transforming the frequency-domain signal; and defining characteristics for an element of a substrate-making process, the characteristics including at least a pattern representing the spatial domain representation and the two-dimensional signal.

Claims

1. A paper-making method including:

defining a two-dimensional signal that encodes plural bits of data;

defining a frequency-domain signal;

inverse transforming the frequency-domain signal to yield a pattern in the spatial domain; and

shaping an element utilized in the paper-making method in accordance with the spatial domain pattern; and

shaping the element of the paper-making method in accordance with a pattern corresponding to the signal that encodes plural bits of data.

2. The method of claim 1 in which the element is a de-watering element.

3. The method of claim 1 in which the two-dimensional signal defines the pattern in the spatial domain.

4. The method of claim 3 further comprising combining the spatial domain pattern and the signal.

5. The method of claim 1, wherein said acts of shaping impart a subliminal pattern on the element.

6. A de-watering element for a paper-making apparatus, characterized in that its surface topology is patterned in accordance with the following method:

defining a two-dimensional signal that encodes plural bits of data;

defining a frequency-domain signal;

inverse transforming the frequency-domain signal to yield a pattern in the spatial domain; and

shaping an element of the paper-making apparatus in accordance with the spatial domain pattern; and

shaping the element of the paper-making apparatus in accordance with a pattern corresponding to the signal that encodes plural bits of data.

7. The element of claim 6 in which the frequency-domain signal comprises plural impulses.

8. The element of claim 6 in which the two-dimensional signal defines the pattern in the spatial domain.

9. The element of claim 6, wherein the shaping of the element imparts a subliminal pattern on the element.

10. A method comprising:

receiving data that corresponds to a two-dimensional signal that encodes plural bits of data;

receiving data that corresponds to a frequency-domain signal, the data corresponding to a representation in a spatial domain through inverse transforming the frequency-domain signal; and

defining characteristics for an element of a substrate-making process, the characteristics including at least a pattern representing the spatial domain representation and the two-dimensional signal.

11. The method of claim 10 in which the element is a de-watering element.

12. The method of claim 10 in which the two-dimensional signal defines the representation pattern in the spatial domain.

13. The method of claim 12 further comprising combining the spatial domain representation and the signal.

14. The method of claim 10, further comprising providing a subliminal pattern on the element.

15. The method of claim 10 further comprising imparting the pattern to a substrate.

16. A substrate imparted with a pattern according to the method of claim 15.

17. A computer-readable medium comprising instructions thereon, the instructions comprising instructions to perform the method of claim 15.

18. The method of claim 10 wherein the substrate comprises at least one substrate from a group of substrates comprising paper or synthetics.

19. A computer or computer hardware programmed to:

receive data that corresponds to a two-dimensional signal that encodes plural bits of data;

receive data that corresponds to a frequency-domain signal, the data corresponding to a representation in a spatial domain through inverse transforming the frequency-domain signal; and

define characteristics for an element of a substrate-making process, the characteristics including at least a pattern representing the spatial domain representation and the two-dimensional signal.

20. A method comprising:

obtaining first information corresponding to a two-dimensional signal associated with plural bits of data;

obtaining second information corresponding to a frequency-domain signal, the second information corresponding to a representation in a spatial domain through inverse transforming the frequency-domain signal; and

specifying characteristics for a component of a substrate-making process, the characteristics including at least a pattern representing the spatial domain representation and the two-dimensional signal.