System reactions to the detection of embedded watermarks in a digital host content

• US 20060239503A1
• Filed: 04/24/2006
• Published: 10/26/2006
• Est. Priority Date: 04/26/2005
• Status: Active Grant

• Current Assignee: IP Acquisitions, LLC
• Original Assignee: Verance Corporation
• Inventors: Petrovic, Rade, Winograd, Joseph M., Tehranchi, Babak
• Granted Patent: US 7,369,677 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G06T 1/0071 using multiple or alternating watermarks
• CPC Class Codes: G10L 19/018 Audio watermarking, i.e. embedding inaudible data in the audio signal
• CPC Class Codes: H04L 2209/608 Watermarking
• CPC Class Codes: H04L 9/002 Countermeasures against attacks on cryptographic mechanisms network architectures or network communication protocols for protection against malicious traffic H04L63/1441
• CPC Class Codes: H04L 9/088 Usage controlling of secret information, e.g. techniques for restricting cryptographic keys to pre-authorized uses, different access levels, validity of crypto-period, different key- or password length, or different strong and weak cryptographic algorithms network architectures or network communication protocols for using time-dependent keys in a packet data network H04L63/068
• CPC Class Codes: H04N 1/00037 Detecting, i.e. determining the occurrence of a predetermined state H04N1/00031 takes precedence
• CPC Class Codes: H04N 1/00872 by image quality reduction, e.g. distortion or blacking out
• CPC Class Codes: H04N 1/00875 Inhibiting reproduction, e.g. by disabling reading or reproduction apparatus
• 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 1/32149 Methods relating to embedding, encoding, decoding, detection or retrieval operations
• CPC Class Codes: H04N 1/32299 using more than one embedding method
• CPC Class Codes: H04N 1/32304 Embedding different sets of additional information
• CPC Class Codes: H04N 1/3232 Robust embedding or watermarking
• CPC Class Codes: H04N 1/32331 Fragile embedding or watermarking
• CPC Class Codes: H04N 2201/323 for tracing or tracking, e.g. forensic tracing of unauthorized copies

Abstract

Methods for adapting the operation of a system in response to the detection of embedded watermarks from a digital host content are provided. A digital host content is received and examined for the presence of watermarks. In response to the detection of embedded watermarks and in accordance with the value, type, density or spacing of the detected watermarks, one or more system reactions may take place. These reactions include conditionally allowing the system to resume its normal operation, prohibiting the system from resuming its normal operation, degrading the quality of the digital host content or changing the security status of the digital host content. In response to the extraction of weak watermarks that do not meet the desired system requirements, the extraction operation may be modified or extended to enable the detection of strong watermarks.

Claims

1. A method for adapting the operation of a watermark extractor in response to watermarks detected in a digital host signal, comprising:

(a) receiving said digital host content;

(b) detecting embedded watermarks in said digital host content;

(c) analyzing the detected watermarks to determine whether any of said detected watermarks comprise strong watermarks; and

(d) if none of the detected watermarks comprise a strong watermark, modifying an operation of the extractor if at least one weak watermark is detected.

2. The method of claim 1, wherein said modifying comprises selecting a different extraction stego key.

3. The method of claim 1, wherein said modifying comprises extending the extractor operation to search at least one additional:

pixel area of said digital host content;

time segment of said digital host content;

spatial frequency range of said digital host content;

temporal frequency range of said digital host content;

color component of said digital host content;

audio channel of said digital host content; and

component of a compressed version of said digital host content.

4. The method of claim 1, wherein said modifying comprises increasing a granularity of watermark detection.

5. The method of claim 1, wherein said modifying comprises at least one of

employing additional error correction code techniques;

and

conducting forensic analysis.

6. A method for adapting the operation of a system in response to watermarks detected in a digital host content, said method comprising:

receiving said digital host content;

detecting embedded watermarks in said digital host content;

analyzing the detected watermarks;

adapting the operation of the system in accordance with said analyzing step by at least one of;

permitting normal operation of said system;

conditionally permitting the operation of said system;

prohibiting the normal operation of said system;

modifying a status of said digital host content; and

degrading a quality of said digital host content.

7. The method of claim 6, wherein said conditionally permitting comprises permitting the operation of said system provided a response from a user, a database, or a third party is received in response to a request from said system.

8. The method of claim 6, wherein said prohibiting comprises at least one of

muting an audio portion of said digital host content;

blanking a video portion of said digital host content; and

stoppage of playback, recording or transfer of said digital host content.

9. The method of claim 6, wherein said modifying the status comprises changing the watermarks of said digital host content.

10. The method of claim 6, wherein said modifying the status comprises changing credentials associated with said digital host content.

11. The method of claim 6, wherein said modifying the status comprises reversibly obscuring said digital host content.

12. The method of claim 6, wherein said degrading comprises at least one of down-sampling, lossy compression, dynamic range reduction, partial scrambling, spectral shaping, addition of vow and flutter, addition of noise, phase distortion, intermittent blanking, and muting of said digital host content.

13. The method of claim 6, wherein said degrading is reversible.

14. The method of claim 6, wherein said degrading is not reversible.

15. A method for adapting the operation of a system in response to the detection of multiple watermark states from a digital host content, comprising:

receiving said digital host content;

detecting embedded watermarks in said digital host content;

analyzing the detected watermarks to determine a watermark state of each of said detected watermarks, each watermark state having a distinct enforcement rule associated therewith; and

selecting one of said enforcement rules associated with said detected watermarks for use in operation of the system.

16. A method in accordance with claim 15, wherein:

the most restrictive enforcement rule associated with said detected watermarks is selected.

17. A method in accordance with claim 15, wherein

the least restrictive enforcement rule associated with said detected watermarks is selected.

18. A Method in accordance with claim 15, wherein:

the watermarks are detected from at least two monitoring intervals; and

an enforcement action is commenced if at least a first watermark state is detected from two or more monitoring intervals, said enforcement action corresponding to said enforcement rule associated with the first watermark state.

19. The method of claim 18, wherein said enforcement action comprises at least one of:

permitting normal operation of said system,

conditionally permitting the operation of said system;

prohibiting the normal operation of said system;

modifying a status of said digital host content; and

degrading a quality of said digital host content.

20. The method of claim 18, wherein said first watermark state is detected in accordance with a predefined value, type, density or spacing.

21. The method of claim 18, wherein said enforcement action is extended in response to the detection of each additional watermark state.

22. The method of claim 18, wherein a duration of said enforcement action is selected randomly.

23. The method of claim 18, wherein a duration of said monitoring intervals is selected randomly.

29. The method of claim 23, wherein:

a new subset of received channels is selected after a time interval;

the channels from the selected new subset are combined to form a new composite signal; and

the watermarks are extracted from the new composite signal.

30. The method of claim 29, wherein a duration of said time interval is random.

24. A method for reducing the computational complexity of watermark extraction from a multi-channel digital host content, comprising:

receiving a multi-channel digital host content;

selecting a subset of received channels of said multi-channel digital host content;

combining the selected subset of received channels to form a composite signal; and

extracting embedded watermarks from said composite signal.

25. The method of claim 24, wherein said selecting is done in accordance with a probability value.

26. The method of claim 25, wherein said probability value has a uniform distribution.

27. The method of claim 25, wherein said probability value has a non-uniform distribution.

28. The method of claim 25, wherein said probability value is calculated in accordance with a number of channels in said multi-channel digital host content.

31. The method of claim 24, wherein said combining comprises:

obtaining a coefficient associated with each selected channel in said subset; and

adding together the selected channels in said subset in accordance with the associated coefficients.

32. The method of claim 31, wherein said coefficients are equally valued.

33. The method of claim 31, wherein said coefficients are selected in accordance with characteristics of the selected channels in said subset.

34. The method of claim 31, wherein said coefficients are selected in accordance with a probability value.