Digital watermarking apparatus and methods

• US 20050141750A1
• Filed: 02/17/2005
• Published: 06/30/2005
• Est. Priority Date: 04/24/2001
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Brundage, Trent J., Rhoads, Geoffrey B., Hannigan, Brett T., Ellingson, Eric E., Rodreguez, Tony F.
• Granted Patent: US 7,164,780 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06Q 10/087 Inventory or stock management, e.g. order filling, procurement or balancing against orders
• CPC Class Codes: G06Q 10/10 Office automation; Time management
• CPC Class Codes: G06T 1/0021 Image watermarking
• CPC Class Codes: G07D 7/0034 using watermarks
• CPC Class Codes: G07D 7/162 Length or width
• CPC Class Codes: G09B 21/003 using tactile presentation of the information, e.g. Braille displays

Abstract

The present invention relates to various digital watermarking methods and systems. In one embodiment, a plurality of microlenses can provide a steganographic signal for a handheld device. The pattern corresponds to (or conveys) a unique device identifier. In yet another embodiment, monetary objects are watermarked with payload information to signify currency denomination. The payload information, once extracted, is used to provide feedback regarding the currency denomination. An audio signal or Braille output can be provided as feedback. In still another embodiment, a document management system is based on watermarks. Embedded watermarks are used to track document history, determine document version information, and enhance overall security. Handheld computing devices are advantageously employed with these embodiments.

Claims

1. A method of determining a size or denomination of a momentary object comprising:

decoding a watermark embedded in a monetary object, the watermark including data corresponding to a denomination of the monetary object; and

based on the data, determining feedback to indicate the denomination of the monetary object; and

providing the feedback.

2. The method according to claim 1, wherein the provided feedback comprises an audible announcement or a series of audible sounds of the denomination of the monetary object.

3. The method according to claim 1, wherein the provided feedback comprises Braille typography indicating the denomination of the monetary object.

4. The method according to claim 1, wherein said decoding comprises analyzing optical scan data corresponding to the monetary object.

5. The method according to claim 1, wherein the provided feedback comprises Braille feedback.

6. The method according to claim 1, wherein a handheld computing device, decodes the watermark.

7. A method of managing documents comprising:

encoding a document with a digital watermark including a document history identifier;

storing the document history identifier in a database, and associating related document history with the document history identifier; and

upon receipt of a decoded digital watermark identifier, indexing the database with the identifier to access the related document history.

8. The method according to claim 7, wherein the related document history comprises document version information.

9. The method according to claim 8, wherein the document version information includes both version information pertaining to the document, and information pertaining to a later version.

10. The method according to claim 7, wherein the related document history comprises one of document version data, creation time, author and last edited information.

11. The method according to claim 7, wherein the identifier comprises at least document version information.

12. A handheld computing device comprising:

a display including a plurality of pixel elements; and

a set of microlenses, wherein each of the set of microlenses corresponds with a pixel element, wherein the microlenses are arranged to create a pattern, the pattern providing to a unique identifier for the device.

13. The handheld computing device of claim 12 wherein the lenses are polarized.

14. The handheld computing device of claim 12 further comprising electronic circuitry communicating with the set of microlenses, wherein the electronic circuitry operates to change the unique identifier.

15. The handheld computing device of claim 12 wherein the unique identifier comprises a steganographic identifier.

16. The handheld computing device of claim 12 wherein the device comprises a cell phone.

17. A handheld device comprising:

an image sensor array comprising a plurality of pixel elements; and

a plurality of lenses, wherein the plurality of lenses are arranged to provide a steganographic signal.

18. The handheld device of claim 17 further comprising electronic circuitry to energize at least some of the lenses, wherein energizing at least some of the lenses changes the steganographic signal.

19. The handheld device of claim 17 wherein the device comprises a cell phone.

20. The handheld device of claim 17 wherein for each pixel element there is provided a lens.