METHODS AND APPARATUS TO PERFORM AUDIO WATERMARKING AND WATERMARK DETECTION AND EXTRACTION

• US 20100106510A1
• Filed: 08/31/2009
• Published: 04/29/2010
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Nielsen Company (US) LLC (RR Donnelley & Sons Company)
• Original Assignee: Nielsen Company (US) LLC (RR Donnelley & Sons Company)
• Inventors: Srinivasan, Venugopal, Topchy, Alexander
• Granted Patent: US 8,359,205 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G06F 16/683 using metadata automatically derived from the content
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: H04H 20/31 using in-band signals, e.g. subsonic or cue signal
• CPC Class Codes: H04H 2201/50 characterised by the use of watermarks
• CPC Class Codes: H04H 60/37 for identifying segments of broadcast information, e.g. scenes or extracting programme ID
• CPC Class Codes: H04H 60/58 of audio determination or detection of speech characteristics in general G10L25/00; speech recognition in general G10L15/00

Abstract

Methods and apparatus to audio watermarking and watermark detection and extracted are described herein. An example method includes receiving a media content signal, sampling the media content signal to generate samples, storing the samples in a buffer, determining a first sequence of samples in the buffer, determining a second sequence of samples in the buffer, wherein the second sequence of samples is of substantially equal length as the first sequence of samples, calculating an average of the first sequence of samples and the second sequence of samples to generate an average sequence of samples, extracting an identifier from the average sequence of samples, and storing the identifier in a tangible memory.

Claims

1. A method to extract identifiers from media content, the method comprising:

receiving a media content signal;

sampling the media content signal to generate digital samples;

storing the samples in a buffer;

determining a first sequence of samples in the buffer;

determining a second sequence of samples in the buffer, wherein the second sequence of samples is of substantially equal length as the first sequence of samples;

calculating an average of the first sequence of samples and the second sequence of samples to generate an average sequence of samples;

extracting an identifier from the average sequence of samples; and

storing the identifier in a tangible memory.

2. A method as defined in claim 1, wherein the media content is an audio signal.

3. A method as defined in claim 1, further comprising determining if a stacking process is to be utilized.

4. A method as defined in claim 3, wherein calculating the average of the first sequence of samples is performed based on the determination.

5. A method as defined in claim 1, wherein calculating the average of the first sequence of samples and the second sequence of samples includes summing the first sequence of samples and the second sequence of samples to generate a summed sequence of samples.

6. A method as defined in claim 5, wherein calculating the average of the first sequence of samples and the second sequence of samples further includes dividing the summed sequence of samples by a number of sequences of samples included in the summed sequence of samples.

7. A method as defined in claim 1, wherein the identifier is repeated in the media content signal after a period of T seconds units and wherein selecting the second sequence of samples comprises selecting a sequence of samples that starts T seconds after a start of the first sequence of samples.

8. A method as defined in claim 1, wherein calculating the average of the first sequence of samples and the second sequence of samples to generate the average sequence of samples comprises calculating the average of the first sequence of samples and the respective ones of the second sequence of samples to generate the average sequence of samples.

9. A computer readable medium storing instructions that, when executed, cause a machine to:

receive a media content signal;

sample the media content signal to generate samples;

store the samples in a buffer;

determine a first sequence of samples in the buffer;

determine a second sequence of samples in the buffer, wherein the second sequence of samples is of substantially equal length as the first sequence of samples;

calculate an average of the first sequence of samples and the second sequence of samples to generate an average sequence of samples;

extract an identifier from the average sequence of samples; and

store the identifier in a tangible memory.

10. A computer readable medium as defined in claim 9, wherein the media content is an audio signal.

11. A computer readable medium as defined in claim 9, wherein the instructions, when executed, further cause the machine to determine if a stacking process is to be utilized.

12. A computer readable medium as defined in claim 11, wherein calculating the average of the first sequence of samples is performed based on the determination.

13. A computer readable medium as defined in claim 9, wherein calculating the average of the first sequence of samples and the second sequence of samples includes summing the first sequence of samples and the second sequence of samples to generate a summed sequence of samples.

14. A computer readable medium as defined in claim 13, wherein calculating the average of the first sequence of samples and the second sequence of samples further includes dividing the summed sequence of samples by a number of sequences of samples included in the summed sequence of samples.

15. A computer readable medium as defined in claim 9, wherein the identifier is repeated in the media content signal after a period of T seconds units and wherein selecting the second sequence of samples comprises selecting a sequence of samples that starts T seconds after a start of the first sequence of samples.

16. A computer readable medium as defined in claim 9, wherein calculating the average of the first sequence of samples and the second sequence of samples to generate the average sequence of samples comprises calculating the average of the first sequence of samples and the respective ones of the second sequence of samples to generate the average sequence of samples.

17. An apparatus to extract identifiers from media content, the apparatus comprising:

a time domain to frequency domain converter to receive a media content signal, sample the media content signal to generate samples, and store the samples in a buffer;

a stacker to determine a first sequence of samples in the buffer, determine a second sequence of samples in the buffer, wherein the second sequence of samples is of substantially equal length as the first sequence of samples, calculate an average of the first sequence of samples and the second sequence of samples to generate an average sequence of samples; and

a decoder to extract an identifier from the average sequence of samples and store the identifier in a tangible memory.

18. An apparatus as defined in claim 17, wherein the media content is an audio signal.

19. An apparatus as defined in claim 17, further comprising a stacker controller to determine if a stacking process is to be utilized.

20. An apparatus as defined in claim 19, wherein calculating the average of the first sequence of samples is performed based on the determination.

21. An apparatus as defined in claim 17, wherein calculating the average of the first sequence of samples and the second sequence of samples includes summing the first sequence of samples and the second sequence of samples to generate a summed sequence of samples.

22. An apparatus as defined in claim 21, wherein calculating the average of the first sequence of samples and the second sequence of samples further includes dividing the summed sequence of samples by a number of sequences of samples included in the summed sequence of samples.

23. An apparatus as defined in claim 17, wherein the identifier is repeated in the media content signal after a period of T seconds units and wherein selecting the second sequence of samples comprises selecting a sequence of samples that starts T seconds after a start of the first sequence of samples.

24. An apparatus as defined in claim 17, wherein calculating the average of the first sequence of samples and the second sequence of samples to generate the average sequence of samples comprises calculating the average of the first sequence of samples and the respective ones of the second sequence of samples to generate the average sequence of samples.