MEDIA PROGRAM IDENTIFICATION METHOD AND APPARATUS BASED ON AUDIO WATERMARKING

• US 20080027734A1
• Filed: 07/25/2007
• Published: 01/31/2008
• Est. Priority Date: 07/26/2006
• Status: Active Grant

• Current Assignee: NEC Company Limited
• Original Assignee: NEC Company Limited
• Inventors: Wei, Yucheng, Zhao, Junhui, Hsueh, Min-Yu
• Granted Patent: US 7,957,977 B2
• Time in Patent Office: Days
• US Class Current: 704/502
• CPC Class Codes: G10L 19/018 Audio watermarking, i.e. embedding inaudible data in the audio signal
• CPC Class Codes: H04N 5/76 Television signal recording

Abstract

The invention provides a method for obtaining related information about a media program containing an audio signal, comprising: an embedding step of embedding an audio watermark containing identification information of the media program into the audio signal of the media program; a transmitting step of transmitting the media program; a recording step of recording by a user a portion of the audio signal of the media program embedded with the audio watermark; an extracting step of extracting the audio watermark from the recorded portion of the audio signal to obtain the identification information and providing the identification information to a server storing the related information; and a related information providing step of providing the user with the related information about the media program according to the identification information from the server, wherein the embedding step comprises: identification information pre-processing step of performing a pre-processing on the identification information of the media program to obtain pre-processed identification information of the media program; echo delay array determining step of determining an echo delay array used in embedding a plurality of pairs of antipodal echoes into the audio signal; amplitude modulating step of modulating amplitudes of the plurality of pairs of antipodal echoes with the pre-processed identification information; echo repeating step of repeating the amplitude-modulated plurality of pairs of antipodal echoes; and echo embedding step of embedding the repeated and amplitude-modulated plurality of pairs of antipodal echoes into the audio signal along the echo delay array.

Claims

1. A method for obtaining related information about a media program containing an audio signal, comprising:

an embedding step of embedding an audio watermark containing identification information of the media program into the audio signal of the media program;

a transmitting step of transmitting the media program;

a recording step of recording by a user a portion of the audio signal of the media program embedded with the audio watermark;

an extracting step of extracting the audio watermark from the recorded portion of the audio signal to obtain the identification information and providing the identification information to a server storing the related information; and

a related information providing step of providing the user with the related information about the media program according to the identification information from the server,

wherein the embedding step comprises;

identification information pre-processing step of performing a pre-processing on the identification information of the media program to obtain pre-processed identification information of the media program;

echo delay array determining step of determining an echo delay array used in embedding a plurality of pairs of antipodal echoes into the audio signal;

amplitude modulating step of modulating amplitudes of the plurality of pairs of antipodal echoes with the pre-processed identification information;

echo repeating step of repeating the amplitude-modulated plurality of pairs of antipodal echoes; and

echo embedding step of embedding the repeated and amplitude-modulated plurality of pairs of antipodal echoes into the audio signal along the echo delay array.

2. The method of claim 1, wherein the identification information includes an identification code of the media program, and wherein the identification information pre-processing step comprises the steps of:

performing an Error Correction Coding on the identification code to obtain a codeword;

performing a redundancy processing on the codeword to produce a redundant sequence;

mapping the redundant sequence into a bit stream by using a Binary Phase Shift Keying modulation;

modulating the bit stream by using a pseudo random sequence modulation to perform a Direct Sequence Spread Spectrum modulation on the bit stream; and

performing a permutation on the Direct Sequence Spread Spectrum modulated bit stream to scramble the order thereof so as to obtain the pre-processed identification information.

3. The method of claim 1 or 2, wherein the echo delay array determining step comprises determining the echo delay array by an analysis-by-synthesis approach.

4. The method of claim 3, wherein the analysis-by-synthesis approach comprises for each echo delay at a sampling rate of the recording step, locating a corresponding embedding position at a sampling rate of the transmitting step so that at that echo delay at the sampling rate of the recording step, the value of the cepstrum autocorrelation coefficient of the recorded portion of the audio signal reaches a maximum.

5. The method of claim 1 or 2, wherein the extracting step further comprises:

cepstrum analyzing step of performing a cepstrum analysis on the recorded portion of the audio signal to obtain the pre-processed identification information of the media program; and

identification information recovering step of recovering the identification information of the media program by performing an inverse-processing of the pre-processing on the pre-processed identification information of the media program.

6. The method of claim 5, wherein the pre-processed identification information includes the pre-processed identification code of the media program, and wherein the identification information recovering step comprises the steps of:

performing a permutation demodulation on the pre-processed identification code to obtain a de-scrambled bit stream;

performing a Direct Sequence Spread Spectrum demodulation on the de-scrambled bit stream to obtain a codeword by using the same pseudo random sequence as used in pre-processing of the identification code; and

performing an Error Correction Decoding on the codeword to recover the identification code.

7. The method of claim 1, wherein the number of the times of the repetition is 2.

8. A system for obtaining related information about a media program containing an audio signal, comprising:

embedding means for embedding an audio watermark containing identification information of the media program into the audio signal of the media program;

transmitting means for transmitting the media program;

recording means for recording a portion of the audio signal of the media program embedded with the audio watermark;

extracting means for extracting the audio watermark from the recorded portion of the audio signal to obtain the identification information and providing the identification information to a server storing the related information; and

related information providing means located on the server for providing the related information about the media program according to the identification information,

wherein the embedding means comprises;

identification information pre-processing means for performing a pre-processing on the identification information of the media program to obtain pre-processed identification information of the media program;

echo delay array determining means for determining an echo delay array used in embedding a plurality of pairs of antipodal echoes into the audio signal;

amplitude modulating means for modulating amplitudes of the plurality of pairs of antipodal echoes with the pre-processed identification information;

echo repeating means for repeating the amplitude-modulated plurality of pairs of antipodal echoes; and

echo embedding means for embedding the repeated and amplitude-modulated plurality of pairs of antipodal echoes into the audio signal along the echo delay array.

9. The system of claim 8, wherein the identification information includes an identification code of the media program, and wherein the identification information pre-processing means comprises:

means for performing an Error Correction Coding on the identification code to obtain a codeword;

means for performing a redundancy processing on the codeword to produce a redundant sequence;

means for mapping the redundant sequence into a bit stream by using a Binary Phase Shift Keying modulation;

means for modulating the bit stream by using a pseudo random sequence modulation to perform a Direct Sequence Spread Spectrum modulation on the bit stream; and

means for performing a permutation on the Direct Sequence Spread Spectrum modulated bit stream to scramble the order thereof so as to obtain the pre-processed identification information.

10. The system of claim 8 or 9, wherein the echo delay array determining means determines the echo delay array by an analysis-by-synthesis approach.

11. The system of claim 10, wherein the analysis-by-synthesis approach comprises for each echo delay at a sampling rate of the recording means, locating a corresponding embedding position at a sampling rate of the transmitting means so that at that echo delay at the sampling rate of the recording means, the value of the cepstrum autocorrelation coefficient of the recorded portion of the audio signal reaches a maximum.

12. The system of claim 8 or 9, wherein the extracting means comprises:

cepstrum analyzing means for performing a cepstrum analysis on the recorded portion of the audio signal to obtain the preprocessed identification information of the media program; and

identification information recovering means for recovering the identification information of the media program by performing an inverse-processing of the pre-processing on the preprocessed identification information of the media program.

13. The system of claim 12, wherein the pre-processed identification information includes the pre-processed identification code of the media program, and wherein the identification information recovering means comprises:

means for performing a permutation demodulation on the pre-processed identification code to obtain a de-scrambled bit stream;

means for performing a Direct Sequence Spread Spectrum demodulation on the de-scrambled bit stream to obtain a codeword by using the same pseudo random sequence as used in pre-processing of the identification code; and

means for performing an Error Correction Decoding on the codeword to recover the identification code.

14. The system of claim 8, wherein the number of the times of the repetition is 2.

15. An apparatus for embedding an audio watermark into an audio signal, comprising:

identification information pre-processing means for performing a pre-processing on identification information related to the audio signal to obtain pre-processed identification information;

echo delay array determining means for determining an echo delay array used in embedding a plurality of pairs of antipodal echoes into the audio signal;

amplitude modulating means for modulating amplitudes of the plurality of pairs of antipodal echoes with the pre-processed identification information;

echo repeating means for repeating the amplitude-modulated plurality of pairs of antipodal echoes; and

echo embedding means for embedding the repeated and amplitude-modulated plurality of pairs of antipodal echoes into the audio signal along the echo delay array.

16. The apparatus of claim 15, wherein the identification information related to the audio signal includes an identification code related to the audio signal, and wherein the identification information pre-processing means comprises:

means for performing an Error Correction Coding on the identification code to obtain a codeword;

means for performing a redundancy processing on the codeword to produce a redundant sequence;

means for mapping the redundant sequence into a bit stream by using a Binary Phase Shift Keying modulation;

means for modulating the bit stream by using a pseudo random sequence modulation to perform a Direct Sequence Spread Spectrum modulation on the bit stream; and

means for performing a permutation on the Direct Sequence Spread Spectrum modulated bit stream to scramble the order thereof so as to obtain the pre-processed identification information.

17. The apparatus of claim 15 or 16, wherein the echo delay array determining means determines the echo delay array by an analysis-by-synthesis approach.

18. The apparatus of claim 17, wherein the analysis-by-synthesis approach comprises for each echo delay at a sampling rate of the recording means, locating a corresponding embedding position at a sampling rate of the transmitting means so that at that echo delay at the sampling rate of the recording means, the value of the cepstrum autocorrelation coefficient of the recorded portion of the audio signal reaches a maximum.

19. The apparatus of claim 15, wherein the number of the times of the repetition is 2.

20. A method for embedding an audio watermark into an audio signal comprising:

identification information pre-processing step of performing a pre-processing on identification information related to the audio signal to obtain pre-processed identification information;

echo delay array determining step of determining an echo delay array used in embedding a plurality of pairs of antipodal echoes into the audio signal;

amplitude modulating step of modulating amplitudes of the plurality of pairs of antipodal echoes with the pre-processed identification information;

echo repeating step of repeating the amplitude-modulated plurality of pairs of antipodal echoes; and

echo embedding step of embedding the repeated and amplitude-modulated plurality of pairs of antipodal echoes into the audio signal along the echo delay array.

21. The method of claim 20, wherein the identification information related to the audio signal includes an identification code related to the audio signal, and wherein the identification information pre-processing step comprises the steps of:

performing an Error Correction Coding on the identification code to obtain a codeword;

performing a redundancy processing on the codeword to produce a redundant sequence;

mapping the redundant sequence into a bit stream by using a Binary Phase Shift Keying modulation;

modulating the bit stream by using a pseudo random sequence modulation to perform a Direct Sequence Spread Spectrum modulation on the bit stream; and

performing a permutation on the Direct Sequence Spread Spectrum modulated bit stream to scramble the order thereof so as to obtain the pre-processed identification information.

22. The method of claim 20 or 21, wherein the echo delay array determining step comprises determining the echo delay array by an analysis-by-synthesis approach.

23. The method of claim 22, wherein the analysis-by-synthesis approach comprises for each echo delay at a sampling rate of the recording step, locating a corresponding embedding position at a sampling rate of the transmitting step so that at that echo delay at the sampling rate of the recording step, the value of the cepstrum autocorrelation coefficient of the recorded portion of the audio signal reaches a maximum.

24. The method of claim 20, wherein the number of the times of the repetition is 2.

25. An apparatus for extracting an audio watermark from an audio signal, wherein the audio watermark is embedded in the audio signal by amplitude-modulating echoes embedded in the audio signal by using pre-processed identification information related to the audio signal, the apparatus comprising:

cepstrum analyzing means for performing a cepstum analysis on the audio signal to obtain the pre-processed identification information; and

identification information recovering means for recovering the identification information by performing an inverse-processing of the pre-processing on the pre-processed identification information.

26. The apparatus of claim 25, wherein the pre-processed identification information includes a pre-processed identification code related to the audio signal, and wherein the identification information recovering means comprises:

means for performing a permutation demodulation on the pre-processed identification code to obtain a de-scrambled bit stream;

means for performing a Direct Sequence Spread Spectrum demodulation on the de-scrambled bit stream to obtain a codeword by using the same pseudo random sequence as used in pre-processing of the identification code; and

means for performing an Error Correction Decoding on the codeword to recover the identification code.

27. A method for extracting an audio watermark from an audio signal, wherein the audio watermark is embedded in the audio signal by amplitude-modulating echoes embedded in the audio signal by using pre-processed identification information related to the audio signal, the method comprising:

cepstrum analyzing step of performing a cepstrum analysis on the audio signal to obtain the pre-processed identification information; and

identification information recovering step of recovering the identification information by performing an inverse-processing of the pre-processing on the pre-processed identification information.

28. The method of claim 27, wherein the pre-processed identification information includes a pre-processed identification code related to the audio signal, and wherein the identification information recovering step comprises the steps of:

performing a permutation demodulation on the pre-processed identification code to obtain a de-scrambled bit stream;

performing a Direct Sequence Spread Spectrum demodulation on the de-scrambled bit stream to obtain a codeword by using the same pseudo random sequence as used in pre-processing of the identification code; and

performing an Error Correction Decoding on the codeword to recover the identification code.