Audio monitoring using steganographic information

• US 6,560,349 B1
• Filed: 12/28/1999
• Issued: 05/06/2003
• Est. Priority Date: 10/21/1994
• Status: Expired due to Fees

• Current Assignee: Digimarc Corporation
• Original Assignee: Digimarc Corporation
• Inventors: Rhoads, Geoffrey B.
• Primary Examiner(s): Johns, Andrew W.
• Application Number:
  US09/473,075
• Time in Patent Office: 1,225 Days
• Field of Search: 382/100, 382/232, 455/2.01, 725/9, 725/14, 725/18, 725/22, 380/231, 380/233, 380/236
• US Class Current: 382/100
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G06Q 20/40145 Biometric identity checks
• CPC Class Codes: G06Q 30/0283 Price estimation or determination
• CPC Class Codes: G06T 1/005 Robust watermarking, e.g. average attack or collusion attack resistant
• CPC Class Codes: G06T 1/0064 Geometric transfor invariant watermarking, e.g. affine transform invariant
• 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: G07C 9/253 visually
• CPC Class Codes: G07D 7/0032 using holograms
• CPC Class Codes: G07D 7/004 using digital security elements, e.g. information coded on a magnetic thread or strip
• CPC Class Codes: G07F 17/16 for devices exhibiting advertisements, announcements, pictures or the like
• 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 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: G07F 7/1016 Devices or methods for securing the PIN and other transaction-data, e.g. by encryption arrangements for secret communication, see H04L9/00
• 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: G11B 20/00094 involving measures which result in a restriction to authorised record carriers
• CPC Class Codes: G11B 20/00115 wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/00166 : involving measures which result in a restriction to authorised contents recorded on or reproduced from a record carrier, e.g. music or software
• CPC Class Codes: G11B 20/00181 : using a content identifier, e.g. an international standard recording code [ISRC] or a digital object identifier [DOI]
• CPC Class Codes: G11B 20/0021 : involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00884 : involving a watermark, i.e. a barely perceptible transformation of the original data which can nevertheless be recognised by an algorithm
• CPC Class Codes: G11B 20/00891 : embedded in audio data
• CPC Class Codes: G11B 2020/10537 : Audio or video recording
• CPC Class Codes: H04B 1/665 : using psychoacoustic properties of the ear, e.g. masking effect
• CPC Class Codes: H04K 1/02 : by adding a second signal to make the desired signal unintelligible
• 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 1/32144 : 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 1/32154 : Transform domain methods H04N1/32309 takes precedence
• CPC Class Codes: H04N 1/3216 : using Fourier transforms
• CPC Class Codes: H04N 1/32208 : involving changing the magnitude of selected pixels, e.g. overlay of information or super-imposition H04N1/32219, H04N1/32224 take precedence
• CPC Class Codes: H04N 1/32251 : in multilevel data, e.g. greyscale or continuous tone data
• CPC Class Codes: H04N 1/32288 : Multiple embedding, e.g. cocktail embedding, or redundant embedding, e.g. repeating the additional information at a plurality of locations in the image
• CPC Class Codes: H04N 2005/91307 : by adding a copy protection signal to the video signal
• CPC Class Codes: H04N 2005/91321 : the copy protection signal being a copy protection control signal, e.g. a record inhibit signal
• CPC Class Codes: H04N 2005/91335 : the copy protection signal being a watermark
• CPC Class Codes: H04N 2005/91342 : the copy protection signal being an authentication signal
• 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 2201/3226 : 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 2201/327 : which are undetectable to the naked eye, e.g. embedded codes
• CPC Class Codes: H04N 2201/3271 : Printing or stamping
• CPC Class Codes: H04N 2201/328 : Processing of the additional information
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection
• CPC Class Codes: H04N 9/8205 : involving the multiplexing of an additional signal and the colour video signal

Abstract

An audio monitoring device includes a microphone for receiving sound energy from a loudspeaker, and a steganographic decoder that decodes the signal produced by the microphone. By reference to the steganographically-decoded information, the device can be used to monitor the musical selections played in a venue for copyright royalty purposes and the like.

Claims

1. An audio monitoring device comprising:

a microphone for receiving sound energy from a loudspeaker; and

a steganographic decoder coupled to the microphone and responsive to data steganographically encoded in a human-audible portion of the sound spectrum so that it is essentially imperceptible to human listeners;

wherein the steganographically encoded data represents at least two fields of information, a first of said fields serving to index sale or distribution information, a second of said fields serving to track particular audio data.

2. The device of claim 1, wherein the steganographically encoded data would have a sound—

if amplified—

like noise.

3. The method of claim 1 wherein at least one of the fields includes error checking information.

4. The method of claim 1 wherein at least one of the fields includes one or more symbols used to interpret symbols in another one of the fields.

5. The method of claim 1 wherein at least one of the fields includes a public code and at least one of the fields includes a private code.

6. The method of claim 1 wherein at least one of the fields is used to memorialize that audio was generated by a particular device, enabling tracing of the audio to the particular device.

7. A method of monitoring, music played over a loudspeaker in an environment, comprising:

using a microphone to produce an electrical signal; and

steganographically decoding from said electrical signal information that is steganographically encoded in a human-audible portion of the sound spectrum so that it is generally imperceptible to human listeners;

wherein the steganographically encoded information represents at least two fields of information, a first of said fields serving to index sale or distribution information, a second of said fields serving to track particular audio data.

8. The method of claim 7 that further includes generating a report detailing music played in said environment by reference to said steganographically decoded information.

9. The method of claim 7 wherein the steganographically encoded data would have a sound—

if amplified—

like noise.

10. The method of claim 7 wherein at least one of the fields includes time or place information used to associate the audio with a public performance of the audio through the steganographically encoded time or place information.

11. The method of claim 7 wherein at least one of the fields includes error checking information.

12. The method of claim 7 wherein at least one of the fields includes one or more symbols used to interpret symbols in another one of the fields.

13. The method of claim 7 wherein at least one of the fields includes a public code and at least one of the fields includes a private code.

14. The method of claim 7 wherein at least one of the fields is used to memorialize that audio was generated by a particular device, enabling tracing of the audio to the particular device.

15. A method of steganographically decoding data from audio comprising:

receiving sound energy from a loudspeaker; and

decoding data steganographically encoded in a human-audible portion of the sound spectrum so that it is essentially imperceptible to human listeners;

wherein the data includes a public code and a private code.

16. The method of claim 15 wherein removal of the public code leaves detectable characteristics of the private code.

17. The method of claim 15 wherein the private code comprises a tracking code.

18. The method of claim 16 wherein the private code comprises a tracking code.

19. The method of claim 15 wherein the public code serves to degrade quality of the audio.

20. The method of claim 19 wherein the public code is removable.

21. The method of claim 20 wherein the public code is removable by software or hardware in response to a transaction relating to the audio.

22. The method of claim 21 wherein the transaction comprises payment for the audio.

23. The method of claim 15 wherein at least one of the codes is used to memorialize that audio was generated by a particular device, enabling tracing of the audio to the particular device.

24. A computer readable medium on which is stored instructions for performing the method of claim 15.

25. A method of steganographically decoding data from audio comprising:

receiving an audio signal representing sound; and

decoding data steganographically encoded in a human-audible portion of the sound spectrum so that it is essentially imperceptible to human listeners;

wherein the data includes a public code and a private code.

26. The method of claim 25 wherein removal of the public code leaves detectable characteristics of the private code.

27. The method of claim 25 wherein the private code comprises a tracking code.

28. The method of claim 26 wherein the private code comprises a tracking code.

29. The method of claim 25 wherein the public code serves to degrade quality of the audio.

30. The method of claim 29 wherein the public code is removable.

31. The method of claim 30 wherein the public code is removable by software or hardware in response to a transaction relating to the audio.

32. The method of claim 31 wherein the transaction comprises payment for the audio.

33. The method of claim 25 wherein at least one of the codes is used to memorialize that audio was generated by a particular device, enabling tracing of the audio to the particular device.

34. The method of claim 25 including:

transferring the audio signal to a remote device for steganographic decoding.

35. The method of claim 34 wherein the remote device performs content monitoring based on the steganographically encoded data.

36. The method of claim 34 wherein the remote device performs metering or royalty tracking based on the steganographically encoded data.

37. The method of claim 25 wherein the public and private codes are embedded into the audio by different devices.

38. The method of claim 25 wherein the public code degrades quality of the audio, but is removable and replaceable by a different public or private code that is substantially imperceptible in the audio.

39. The method of claim 38 wherein the different code serves to track the audio.

40. The method of claim 39 wherein the different code is inserted in the audio at the time of a commercial transaction relating to the audio.

41. The method of claim 40 wherein the commercial transaction comprises a purchase of the audio signal.

42. A computer readable medium on which is stored instructions for performing the method of claim 25.