METHODS AND APPARATUS TO EXTRACT DATA ENCODED IN MEDIA CONTENT

• US 20120101827A1
• Filed: 12/30/2011
• Published: 04/26/2012
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: The Nielsen Company LLC (MOOD Media Corporation)
• Original Assignee: The Nielsen Company LLC (MOOD Media Corporation)
• Inventors: Topchy, Alexander Pavlovich, Srinivasan, Venugopal
• Granted Patent: US 8,554,545 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• 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 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 extract data encoded in media content are disclosed. An example method includes sampling a media content signal to generate digital samples, determining a frequency domain representation of the digital samples, determining a first rank of a first frequency in the frequency domain representation, determining a second rank of a second frequency in the frequency domain representation, combining the first rank and the second rank with a set of ranks to create a combined set of ranks, comparing the combined set of ranks to a set of reference sequences, determining a data represented by the combined set of ranks based on the comparison, and storing the data in a memory device.

Claims

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

sampling a media content signal to generate digital samples;

determining a frequency domain representation of the digital samples;

determining a first rank of a first frequency in the frequency domain representation;

determining a second rank of a second frequency in the frequency domain representation;

combining, via a processor, the first rank and the second rank with a set of ranks to create a combined set of ranks;

comparing the combined set of ranks to a set of reference sequences;

determining information represented by the combined set of ranks based on the comparison; and

storing the data in a memory device.

2. A method as defined in claim 1, wherein comparing the combined set of ranks to the reference set of ranks includes determining a set of distances between the combined set of ranks and one or more of the sequences in the reference set of sequences.

3. A method as defined in claim 2, wherein determining the data represented by the combined set of ranks includes selecting a sequence in the reference set of sequences that has the smallest distance.

4. A method as defined in claim 1, wherein the first rank indicates an amplitude of the first frequency of interest relative to other frequencies in a neighborhood.

5. A method as defined in claim 4, wherein a number of frequencies in the neighborhood is equal to a number of possible rank values.

6. A method as defined in claim 1, further comprising determining a first average rank for a first frequency in the frequency domain representation and determining a second average rank for a second frequency in the frequency domain representation.

7. A method as defined in claim 6, wherein the information is encoded in the media content signal after T seconds and wherein determining a first average rank for the first frequency comprises determining a third rank for a first frequency approximately T seconds before determining the first rank and adding the first rank and the third rank.

8. An apparatus to extract information from media content, the apparatus comprising:

a sampler to sample a media content signal to generate digital samples;

a time domain to frequency domain converter to determine a frequency domain representation of the digital samples;

a ranker to determine a first rank of a first frequency in the frequency domain representation and to determine a second rank of a second frequency in the frequency domain representation; and

a comparator to combine the first rank and the second rank with a set of ranks to create a combined set of ranks, to compare the combined set of ranks to a set of reference sequences, and to determine information represented by the combined set of ranks based on the comparison.

9. An apparatus as defined in claim 8, wherein the comparator is to compare the combined set of ranks to the reference set of ranks by determining a set of distances between the combined set of ranks and one or more of the sequences in the reference set of sequences.

10. An apparatus as defined in claim 9, wherein the comparator is to determine the data represented by the combined set of ranks by selecting a sequence in the reference set of sequences that has the smallest distance.

11. An apparatus as defined in claim 8, wherein the first rank indicates an amplitude of the first frequency relative to other frequencies in a neighborhood.

12. An apparatus as defined in claim 11, wherein a number of frequencies in the neighborhood is equal to a number of possible rank values.

13. An apparatus as defined in claim 8, further comprising a stacker to determine a first average rank for a first frequency in the frequency domain representation and to determine a second average rank for a second frequency in the frequency domain representation.

14. An apparatus as defined in claim 13, wherein the information is encoded in the media content signal after T seconds and wherein the ranker is to determine a first average rank for the first frequency by determining a third rank for a first frequency approximately T seconds before determining the first rank and by adding the first rank and the third rank.

15. A tangible computer readable medium excluding propagating signals and storing instructions that, when executed, cause a machine to extract information from media content by at least:

sampling a media content signal to generate digital samples;

determining a frequency domain representation of the digital samples;

determining a first rank of a first frequency in the frequency domain representation;

determining a second rank of a second frequency in the frequency domain representation;

combining the first rank and the second rank with a set of ranks to create a combined set of ranks;

comparing the combined set of ranks to a set of reference sequences; and

determining information represented by the combined set of ranks based on the comparison.

16. A computer readable medium as defined in claim 15, wherein the instructions cause the machine to compare the combined set of ranks to the reference set of ranks by determining a set of distances between the combined set of ranks and one or more of the sequences in the reference set of sequences.

17. A computer readable medium as defined in claim 16, wherein the instructions cause the machine to determine the data represented by the combined set of ranks by selecting a sequence in the reference set of sequences that has the smallest distance.

18. A computer readable medium as defined in claim 15, wherein the first rank indicates an amplitude of the first frequency relative to other frequencies in a neighborhood.

19. A computer readable medium as defined in claim 18, wherein a number of frequencies in the neighborhood is equal to a number of possible rank values.

20. A computer readable medium as defined in claim 15, wherein the instructions cause the machine to determine a first average rank for a first frequency in the frequency domain representation and determine a second average rank for a second frequency in the frequency domain representation.

21. A computer readable medium as defined in claim 20, wherein the instructions cause the machine to encode the information in the media content signal after T seconds and wherein the instructions cause the machine to determine a first average rank for the first frequency by determining a third rank for a first frequency approximately T seconds before determining the first rank and adding the first rank and the third rank.