Digital watermarks

• US 20030219144A1
• Filed: 03/03/2003
• Published: 11/27/2003
• Est. Priority Date: 05/08/1995
• Status: Active Grant

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rhoads, Geoffrey B., Carr, J. Scott
• Granted Patent: US 7,263,203 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: B29C 45/1418 the inserts being deformed or preformed, e.g. by the injection pressure
• CPC Class Codes: B42D 25/29 Securities; Bank notes
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06T 1/0028 Adaptive watermarking, e.g. Human Visual System [HVS]-based watermarking
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 1/0078 using multiple thresholds
• CPC Class Codes: G06T 2201/0052 Embedding of the watermark in the frequency domain
• CPC Class Codes: G06T 2201/0065 Extraction of an embedded watermark; Reliable detection
• 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: G06V 30/40 Document-oriented image-based pattern recognition
• CPC Class Codes: G07C 9/253 visually
• CPC Class Codes: G07D 7/0034 using watermarks
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07F 7/08 by coded identity card or credit card or other personal identification means without personal verification means G07F7/02
• CPC Class Codes: G07F 7/086 by passive credit-cards adapted therefor, e.g. constructive particularities to avoid counterfeiting, e.g. by inclusion of a physical or chemical security-layer for security documents G07D7/00; for the reading of record-carriers in general G06K7/00; for the design of coded credit-cards G06K19/10
• CPC Class Codes: G07F 7/12 Card verification
• CPC Class Codes: G10L 19/018 Audio watermarking, i.e. embedding inaudible data in the audio signal
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: H04N 1/00005 relating to image data
• CPC Class Codes: H04N 1/00037 Detecting, i.e. determining the occurrence of a predetermined state H04N1/00031 takes precedence
• CPC Class Codes: H04N 1/00079 : remotely
• CPC Class Codes: H04N 1/00838 : Preventing unauthorised reproduction
• CPC Class Codes: H04N 1/32122 : in a separate device, e.g. in a memory or on a display separate from image data
• CPC Class Codes: H04N 1/32144 : embedded in the image data, i.e. enclosed or integrated in the image, e.g. watermark, super-imposed logo or stamp
• CPC Class Codes: H04N 1/32219 : involving changing the position of selected pixels, e.g. word shifting, or involving modulating the size of image components, e.g. of characters H04N1/32224 takes precedence
• CPC Class Codes: H04N 1/32261 : in binary data H04N1/32256 takes precedence
• CPC Class Codes: H04N 1/32304 : Embedding different sets of additional information
• CPC Class Codes: H04N 1/32352 : Controlling detectability or arrangements to facilitate detection or retrieval of the embedded information, e.g. using markers for decoding, detection or retrieval operations H04N1/32149 and subgroups take precedence
• CPC Class Codes: H04N 21/23892 : involving embedding information at multiplex stream level, e.g. embedding a watermark at packet level
• CPC Class Codes: H04N 21/8358 : involving watermark protecting executable software by watermarking G06F21/16; image watermarking in general G06T1/0021; watermarks inserted in still images for transmission purposes H04N1/32144; inserting watermarks during video coding H04N19/467
• CPC Class Codes: H04N 2201/3205 : of identification information, e.g. name or ID code H04N2201/3209 takes precedence
• CPC Class Codes: H04N 2201/3207 : of an address
• CPC Class Codes: H04N 2201/3225 : of data relating to an image, a page or a document
• CPC Class Codes: H04N 2201/3226 : of identification information or the like, e.g. ID code, index, title, part of an image, reduced-size image
• CPC Class Codes: H04N 2201/3233 : of authentication information, e.g. digital signature, watermark
• CPC Class Codes: H04N 2201/3239 : using a plurality of different authentication information
• CPC Class Codes: H04N 2201/327 : which are undetectable to the naked eye, e.g. embedded codes
• CPC Class Codes: H04N 2201/3271 : Printing or stamping
• CPC Class Codes: H04N 2201/3274 : Storage or retrieval of prestored additional information
• CPC Class Codes: H04N 2201/328 : Processing of the additional information

Abstract

An iterative encoding technique assesses trial watermark encoding of an object, and redresses any detected shortcomings in one or more successive re-encodings of the object. Other improvements concern web crawler-based watermark detectors, novel uses of meta-data in watermarks, applications of watermarks in merchandising, embedding of active computer code via watermarks, watermark-based asset management systems, watermark processing of computer system clock signals, and watermarks in labels and tags.

Claims

1. In a method of encoding an object in accordance with a plural-bit digital watermark, an improvement comprising:

encoding the object with said plural-bit watermark in accordance with initial encoding parameters;

decoding the plural-bit watermark from the encoded object;

assessing the decoded plural-bit watermark;

adjusting at least one of said encoding parameters; and

encoding the object with said plural-bit watermark in accordance with the adjusted encoding parameters;

wherein more reliable detection of each bit of the plural-bit watermark may be achieved.

2. The method of claim 1, which further includes distributing the object after encoding in accordance with the adjusted encoding parameters.

3. The method of claim 1 which includes determining a figure of merit for each decoded bit.

4. The method of claim 3 in which the figure of merit is a signal-to-noise ratio associated with each decoded bit.

5. The method of claim 1 which includes iteratively changing parameters, encoding, and assessing, until all of the decoded bits meet a predetermined figure of merit.

19. The method of claim 1 that includes subjecting the encoded object to corruption prior to said decoding.

20. The method of claim 19 that includes subjecting the encoded object to a lossy process including both compression and decompression prior to said decoding.

21. A storage medium having stored thereon an encoded object produced according to the method of claim 20.

22. A storage medium having stored thereon instructions causing a computer to perform the method of claim 1.

6. In a method of encoding an object in accordance with watermark data, an improvement comprising:

encoding the object with said watermark data in accordance with initial encoding parameters;

analyzing the encoded object in portions to assess the encoded watermark data in each portion;

adjusting at least one of said encoding parameters; and

encoding the object with said watermark data in accordance with the adjusted encoding parameters;

wherein more reliable detection of the watermark data from excerpts of the encoded object may be achieved.

7. The method of claim 6 in which the portions comprise rectangular patches of image data.

8. The method of claim 6 in which the portions comprise temporal excerpts of video or audio data.

9. The method of claim 6 in which the portions comprise coefficients representing the object in a transformed domain.

10. The method of claim 6 which includes iteratively changing parameters, encoding, and analyzing until all of the portions meet a predetermined figure of merit.

23. The method of claim 6 that includes subjecting the encoded object to corruption prior to said decoding.

24. The method of claim 23 that includes subjecting the encoded object to a lossy including both compression and decompression process prior to said decoding.

25. A storage medium having stored thereon an encoded object produced according to the method of claim 24.

26. A storage medium having stored thereon instructions causing a computer to perform the method of claim 6.

11. In a computer-implemented method of encoding an object in accordance with watermark data, an improvement comprising:

(a) initially encoding the object with the watermark data in accordance with one or more initial encoding parameters;

(b) analyzing the encoded object to assess the encoded watermark data therein;

(c) if the analysis indicates that the initial encoding did not meet a performance metric, automatically adjusting at least one of said encoding parameters, re-watermarking, and re-analyzing in an iterative fashion in an attempt to meet the performance metric.

12. The method of claim 11 that includes alerting an operator if (c) fails to yield an encoded object that meets the performance metric.

13. The method of claim 11 that includes subjecting the encoded object to corruption prior to each of said analyzing operations.

14. The method of claim 13 in which the corruption comprises a lossy process that includes both compression and decompression.

15. The method of claim 11 in which the performance metric is strength of the watermark detected from the encoded object.

16. The method of claim 11 in which the performance metric is speed of watermark decoding.

17. The method of claim 11 in which the performance metric is a bit rate associated with the encoded object.

18. The method of claim 11 in which:

the watermark data comprises plural bits; and

the performance metric indicates the confidence by which each bit can be decoded from the encoded object.

27. A storage medium having stored thereon an encoded object produced according to the method of claim 11.

28. A storage medium having stored thereon instructions causing a computer to perform the method of claim 11.

29. A method of steganographic encoding of content data, comprising:

receiving first content data that has been steganographically trial-encoded;

corrupting the trial-encoded content data;

assessing a result of said corruption; and

providing information obtained through said assessment to a subsequent process that is to steganographically encode the content data.

30. The method of claim 29 in which the corrupting includes applying a lossy compression process to the trial-encoded content data.

31. The method of claim 29 in which the corrupting includes rendering the trial-encoded content data into human perceptible form, and thereafter sampling back said human perceptible form to produce corresponding digital data.

32. The method of claim 29 that includes performing a steganographic encoding process to generate said first content data.

33. The method of claim 29 that includes using information obtained through said assessment in performing said subsequent steganographic encoding process on said content data.

34. The method of claim 33 that further includes publicly distributing the watermarked content thus produced.

35. A computer storage medium having stored thereon watermarked entertainment content data produced according to the method of claim 33.

36. A computer storage medium having stored thereon instructions causing a computer to perform the method of claim 29.

37. (New) The method of claim 29 wherein the steganographic encoding comprises a unique identifier.

38. (New) The method of claim 37 wherein the identifier is used for content tracking.

39. A method of steganographically encoding content with plural-bit data, said method comprising the steps of:

subjecting the content to an initial encoding process;

altering the form of the initially encoded content;

determining a measure to account for the altering of the initially encoded content; and

adjusting at least one parameter of a subsequent encoding process according to the measure; and

encoding the content with the plural-bit data according to the adjusted subsequent encoding process.

40. The method of claim 39 wherein said altering step comprises applying a lossy compression process to the initially encoded content.