PERCEPTABILITY MODEL APPLIED TO WATERMARK SIGNALS

• US 20090087018A1
• Filed: 03/28/2008
• Published: 04/02/2009
• Est. Priority Date: 04/15/2003
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rogers, Eliot, Reed, Alastair M.
• Granted Patent: US 8,098,882 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 2201/0051 Embedding of the watermark in the spatial domain
• 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 1/32149 Methods relating to embedding, encoding, decoding, detection or retrieval operations
• CPC Class Codes: H04N 1/32192 according to calculated or estimated visibility of the additional information in the image
• CPC Class Codes: H04N 1/32229 with selective or adaptive application of the additional information, e.g. in selected regions of the image H04N1/32213 takes precedence
• CPC Class Codes: H04N 1/32309 in colour image data
• CPC Class Codes: H04N 1/3232 Robust embedding or watermarking

Abstract

This document relates generally to digital watermarking. One claim recites a method including: obtaining data representing visual media; determining a model through iteratively embedding a digital watermark signal in the data; and embedding the digital watermark signal in the data according to the model. The model maximizes robustness of the digital watermark signal while minimizing perceptibility of the digital watermark signal when the signal is embedded in the data. A new embedding form or embedding mask is created after each embedding iteration. Of course, other combinations are described and claimed as well.

Claims

1. A method comprising:

obtaining data representing visual media;

analyzing the data to determine perceptibility attributes of the data;

varying a digital watermark signal relative to the data with reference to the perceptibility attributes, said act of varying maintains a predetermined perceptibility level across the signal;

embedding the digital watermark signal in the data.

2. The method of claim 1 wherein said act of analyzing comprises color conversion that converts.

3. The method of claim 2 where said analyzing further comprises visibility metric analysis to compute perceptibility attributes areas within the data.

4. The method of claim 1 further comprising—

after an initial act of embedding—

iteratively determining perceptibility attributes of the data.

5. The method of claim 4 wherein said act of iteratively determining creates a new embedding form or embedding mask after each embedding iteration.

6. A computer readable medium comprising instructions or circuitry to perform the method of claim 1.

7. A computer readable medium comprising instructions or circuitry to perform the method of claim 5.

8. The method of claim 1 wherein said act of varying varies the digital watermark signal relative to the data with reference to both the perceptibility attributes and a model of an expected rendering device.

9. A method comprising:

obtaining data representing visual media;

determining a model which maximizes robustness of a digital watermark signal while minimizing perceptibility of the digital watermark signal when the signal is embedded in the data;

embedding the digital watermark signal in the data according to the model.

10. The method of claim 9 wherein the model comprises color converting the data.

11. The method of claim 9 wherein the robustness or perceptibility relies on color attributes of the data.

12. The method of claim 9 wherein the model is developed through iteratively embedding the digital watermark signal in the data.

13. The method of claim 12 wherein a new embedding form or embedding mask is created after each embedding iteration.

14. A computer readable medium comprising instructions or circuitry to perform the method of claim 9.

15. A computer readable medium comprising instructions or circuitry to perform the method of claim 12.

16. A computer readable medium comprising instructions or circuitry to perform the method of claim 13.

17. The method of claim 9 wherein the model utilizes an approximation of an expected rendering device.

18. A method comprising:

obtaining data representing visual media;

determining a model through iteratively embedding a digital watermark signal in the data, the model maximizing robustness of the digital watermark signal while minimizing perceptibility of the digital watermark signal when the signal is embedded in the data, wherein a new embedding form or embedding mask is created after each embedding iteration;

embedding the digital watermark signal in the data according to the model.

19. A computer readable medium comprising instructions or circuitry to perform the method of claim 18.