Comparison of data signals using characteristic electronic thumbprints extracted therefrom
A characteristic thumbprint is extracted from a data signal, the thumbprint based on statistics relating to the data signal. The data signal can be compared indirectly by matching this thumbprint against one or more reference thumbprints. The data signal may be any type of signal, including streaming digitized audio or obtained from static files. A database may contain a number of these characteristic thumbprints, and the database can be searched for a particular thumbprint.
1. A method comprising:
filtering, by a computer processor, a data signal to produce a plurality of filtered signals, at least two of the filtered signals having a different frequency range;
for each filtered signal in the plurality of filtered signals, scanning, by the computer processor, the each filtered signal for one or more peaks, each peak found from an average total power calculated for the each filtered signal for a series of sample periods;
determining characteristic data for the data signal, by the computer processor, wherein the characteristic data for the data signal is determined based on the one or more peaks;
extracting, by the computer processor, a digital thumbprint from the data signal based on content of the data signal, the digital thumbprint comprising the determined characteristic data for the data signal; and
storing, by the computer processor, the digital thumbprint on a non-transitory computer-readable storage medium.
2. The method of claim 1 , wherein the data signal contains encoded content from a group of encoded content consisting of encoded media content, encoded audio content, and encoded video content.
3. The method of claim 1 , further comprising: receiving the data signal as streaming media over a network.
4. The method of claim 1 , further comprising: receiving the data signal in real time over a network.
5. The method of claim 1 , further comprising: sampling a broadcast signal to obtain the data signal.
6. The method of claim 1 , wherein the plurality of filtered signals have frequency ranges that are in a logarithmically even fashion.
7. The method of claim 1 , wherein each of the one or more peaks is defined as maximum absolute value of amplitude within an interval around the each of the one or more peaks.
8. The method of claim 1 , further comprising calculating the average total power for the each filtered signal for the series of sample periods.
9. The method of claim 1 , wherein the characteristic data for the data signal is determined using a statistical function comprising the ratio of the standard deviation to the mean of measures of power computed for the each filtered signal.
10. A system comprising:
a processor;
a storage medium for tangibly storing thereon program logic for execution by the processor, the program logic comprising:
filtering logic executed by the processor for filtering a data signal to produce a plurality of filtered signals, at least two of the filtered signals having a different frequency range;
scanning logic executed by the processor for scanning, for each filtered signal in the plurality of filtered signals, the each filtered signal for one or more peaks, each peak found from an average total power calculated for the each filtered signal for a series of sample periods;
determining logic executed by the processor for determining characteristic data for the data signal, wherein the characteristic data for the data signal is determined based on the one or more peaks;
extracting logic executed by the processor for extracting a digital thumbprint from the data signal based on content of the data signal, the digital thumbprint comprising the determined characteristic data for the data signal; and
storing logic executed by the processor for storing the digital thumbprint on a non-transitory computer-readable storage medium.
11. The system of claim 10 , wherein the data signal contains encoded content from a group of encoded content consisting of encoded media content, encoded audio content, and encoded video content.
12. The system of claim 10 , further comprising: receiving logic executed by the processor for receiving the data signal as streaming media over a network.
13. The system of claim 10 , further comprising: receiving logic executed by the processor for receiving the data signal in real time over a network.
14. The system of claim 10 , further comprising: sampling logic executed by the processor for sampling a broadcast signal to obtain the data signal.
15. The system of claim 10 , wherein the plurality of filtered signals have frequency ranges that are in a logarithmically even fashion.
16. The system of claim 10 , wherein each of the one or more peaks is defined as maximum absolute value of amplitude within an interval around the each of the one or more peaks.
17. The system of claim 10 , further comprising calculating logic executed by the processor for calculating the average total power for the each filtered signal for the series of sample periods.
18. The system of claim 10 , wherein the characteristic data for the data signal is determined using a statistical function comprising the ratio of the standard deviation to the mean of measures of power computed for the each filtered signal.
19. A non-transitory computer readable storage medium comprising computer program code for execution by a processor, the computer program code comprising instructions for:
filtering, by the processor, a data signal to produce a plurality of filtered signals, at least two of the filtered signals having a different frequency range;
for each filtered signal in the plurality of filtered signals, scanning, by the processor, the each filtered signal for one or more peaks, each peak found from an average total power calculated for the each filtered signal for a series of sample periods;
determining characteristic data for the data signal, by the processor, wherein the characteristic data for the data signal is determined based on the one or more peaks;
extracting, by the processor, a digital thumbprint from the data signal based on content of the data signal, the digital thumbprint comprising the determined characteristic data for the data signal; and
storing, by the processor, the digital thumbprint on a non-transitory computer-readable storage medium.
20. The non-transitory computer readable storage medium of claim 19 , further comprising instructions for calculating, by the processor, the average total power for the each filtered signal for the series of sample periods.