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

• US 8,280,103 B2
• Filed: 11/19/2010
• Issued: 10/02/2012
• Est. Priority Date: 04/26/2005
• Status: Active Grant

• Current Assignee: Verance Corporation
• Original Assignee: Verance Corporation
• Inventors: Petrovic, Rade, Tehranchi, Babak, Winograd, Joseph
• Primary Examiner(s): Le, Vu
• Assistant Examiner(s): Allison, Andrae S
• Application Number:
  US12/950,943
• Publication Number:
  US 20110286625A1
• Time in Patent Office: 683 Days
• Field of Search: 382/100, 382/232, 380/20, 380/28, 380/54, 713/176, 713/179, 713/181
• 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, devices and computer program products for enabling secure and efficient extraction of embedded watermarks from digital host content are provided. Upon the reception of a multi-channel digital host content with embedded watermarks, a subset of the received channels are selected and combined together to form a composite content. The composite content is then examined to recover embedded watermarks. The particular subset of channels can be selected according to a probability value. Further, a set of new channels can be selected and combined after a particular time interval has elapsed. The number of selected channels can also be varied each time a new selection is made.

Claims

1. A method for watermark extraction from a multi-channel digital host content, comprising:

receiving a multi-channel digital host content;

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

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

extracting embedded watermarks from the composite contents;

selecting a new subset of received channels after a time interval has elapsed;

combining the new subset of received channels to form a new composite content; and

extracting embedded watermarks from the new composite content.

2. The method of claim 1, wherein the selecting of the subset of received channels is carried out in accordance with a probability value.

3. The method of claim 2, wherein the probability value is selected from one of a uniform or non-uniform probability distributions.

4. The method of claim 2, wherein the probability value is calculated in accordance with a number of channels in the multi-channel digital host content.

5. The method of claim 2, wherein the probability value is calculated in accordance with a history of a particular subset of received channels.

6. The method of claim 1, wherein the selecting of the subset includes excluding some channels from the subset based on their content.

7. The method of claim 1, wherein the duration of the time interval is selected randomly from within a range of time interval values.

8. The method of claim 1, wherein the time interval is selected based on a balancing of a desired level of robustness with available computational resources.

9. The method of claim 1, wherein the combining of the selected subset of received channels comprises:

obtaining a coefficient associated with each selected channel; and

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

10. The method of claim 9, wherein the adding together comprises multiplying each individual channel by its associated coefficient and adding the products of the multiplication for each channel.

11. The method of claim 9, wherein the coefficients have equal values.

12. The method of claim 9, wherein the coefficients are independent of the associated channels.

13. The method of claim 9, wherein the coefficients are selected in accordance with an inherent characteristic of the selected channels.

14. The method of claim 13, wherein the selection of coefficients is based on an ability of the selected channels to carry embedded watermarks.

15. The method of claim 13, wherein the inherent characteristic is selected from the group consisting of:

an amplitude variation of the selected channel;

a frequency distribution of the selected channel;

an energy profile of the selected channel; and

spatial location of the selected channel within a multi-channel audio content.

16. The method of claim 9, wherein the coefficients are selected in accordance with a probability value.

17. A device, comprising:

a processor; and

a memory comprising processor executable code, the processor executable code, when executed by the processor, configures the device to;

receive a multi-channel digital host content;

select a subset of received channels of the multi-channel digital host content;

combine the selected subset of received channels to form a composite content;

extract embedded watermarks from the composite content;

select a new subset of received channels after a time interval has elapsed;

combine the new subset of received channels to form a new composite content; and

extract embedded watermarks from the new composite content.

18. The device of claim 17, wherein the processor executable code, when executed by the processor, configures the device to select the subset of received channels in accordance with a probability value.

19. The device of claim 18, wherein the probability value is selected from one of a uniform or non-uniform probability distributions.

20. The device of claim 18, wherein the probability value is calculated in accordance with a number of channels in the multi-channel digital host content.

21. The device of claim 18, wherein the probability value is calculated in accordance with a history of a particular subset of received channels.

22. The device of claim 17, wherein the processor executable code, when executed by the processor, configures the device to select the subset of received channel by excluding some channels from the subset based on their content.

23. The device of claim 17, wherein the duration of the time interval is selected randomly from within a range of time interval values.

24. The device of claim 17, wherein, as part of configuring the device to combine the subset of received channels, the processor executable code, when executed by the processor, configures the device to:

obtain a coefficient associated with each selected channel; and

add together the selected channels in accordance with the associated coefficients.

25. The device of claim 24, wherein, as part of configuring the device to add together the selected channels, the processor executable code, when executed by the processor, configures the device to multiply each individual channel by its associated coefficient and add the products of the multiplication for each channel.

26. The device of claim 24, wherein the coefficients have equal values.

27. The device of claim 24, wherein the coefficients are selected in accordance with an inherent characteristic of the selected channels.

28. The device of claim 27, wherein the selection of coefficients is based on an ability of the selected channels to carry embedded watermarks.

29. The device of claim 27, wherein the inherent characteristic is selected from the group consisting of:

an amplitude variation of the selected channel;

a frequency distribution of the selected channel;

an energy profile of the selected channel; and

spatial location of the selected channel in a multi-channel audio content.

30. The device of claim 24, wherein the coefficients are selected in accordance with a probability value.

31. A non-transitory computer readable medium with program code embodied thereupon, the program code configured to:

receive a multi-channel digital host content;

select a subset of received channels of the multi-channel digital host content;

combine the selected subset of received channels to form a composite content;

extract embedded watermarks from the composite content;

select a new subset of received channels after a time interval has elapsed;

combine the new subset of received channels to form a new composite content; and

extract embedded watermarks from the new composite content.

32. A non-transitory computer-readable medium with a multi-channel digital host content embodied thereupon, the multi-channel digital host content comprising:

one or more watermarks that are imperceptibly embedded in at least one of the channels of the multi-channel digital host content, wherein upon reception of the multi-channel digital host content by a content handling device equipped with a watermark extractor, the watermark extractor is triggered to;

select a subset of received channels of the multi-channel digital host content;

combine the selected subset of received channels to form a composite content;

extract embedded watermarks from the composite content;

select a new subset of received channels after a time interval has elapsed;

combine the new subset of received channels to form a new composite content; and

extract embedded watermarks from the new composite content.