Broadcast signal identification system

• US 3,919,479 A
• Filed: 04/08/1974
• Issued: 11/11/1975
• Est. Priority Date: 09/21/1972
• Status: Expired due to Term

• Current Assignee: AC Nielsen Company Nielsen Plaza Northbrook ILL A Corporation of
• Original Assignee: Richard J. Weiner, Robert A. Hansen, Robert N. Linde, Warren D. Moon
• Inventors: Moon, Warren D., Weiner, Richard J., Hansen, Robert A., Linde, Robert N.
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Kemeny, E. S.
• Application Number:
  US05/458,978
• Time in Patent Office: 582 Days
• Field of Search: 343/1CL 235/181 179/1SA,1SB
• US Class Current: 704/237
• CPC Class Codes: G06F 2218/16 by matching signal segments
• CPC Class Codes: G10L 15/10 using distance or distortion measures between unknown speech and reference templates
• CPC Class Codes: G10L 25/06 the extracted parameters being correlation coefficients
• CPC Class Codes: H04H 60/37 for identifying segments of broadcast information, e.g. scenes or extracting programme ID
• CPC Class Codes: H04H 60/44 for identifying broadcast stations
• CPC Class Codes: H04H 60/56 Arrangements characterised by components specially adapted for monitoring, identification or recognition covered by groups H04H60/29-H04H60/54

Abstract

A process for automatic electronic recognition and identification of programs and commercial advertisements broadcast on television and radio wherein a digitally sampled reference signal segment derived from either the audio or video portion of the original program content to be identified is compared with successive digitally sampled segments of the corresonding audio or video portion of a broadcast signal in a correlation process to produce a correlation function signal. The sampling rates and the time duration of the reference signal segment and the broadcast signal segments are the same. When the signal segments which are compared are the same, the correlation function signal is relatively large and a recognition thereof is achieved when such correlation function signal exceeds a selected threshold level. The compared signal segments may also be obtained as low frequency signals derived from the original reference and broadcast signals by non-linear and envelope formation processing techniques.

Claims

1. A process for automatic electronic recognition and identification of programs and commercial advertisements broadcast on television and radio, said process comprising the steps of processing a reference signal which constitutes the program or commercial advertisement to be identified to produce a processed reference signal having frequency components in the sub-audio frequency range corresponding to the syllabic frequency rates of the inFormation content of said signal to be identified;

generating a digitally sampled reference signal segment having a selected sampling rate and time duration, said reference signal segment representing at least a part of said processed referenced signal;

processing a broadcast signal in the same manner as said reference signal so as to produce a processed broadcast signal having frequency components in the sub-audio frequency range corresponding to the syllabic frequency rates of the information content of said broadcast signal;

generating a plurality of successive digitally sampled broadcast signal segments, each said digitally sampled broadcast signal segment having the same sampling rate and time duration as the selected sampling rate and time duration of said reference signal segment;

correlating each successive broadcast signal segment with said reference signal segment to produce a correlation function signal which has a relatively small amplitude level when said correlated signal segments are different and a relatively large amplitude level when said correlated signal segments are the same; and

sensing the amplitude level of said correlation function signal to provide a recognition signal when the amplitude of said correlation function signal exceeds a selected threshold level to identify the presence of said program or commercial advertisement in said broadcast signal.

2. A process in accordance with claim 1 wherein said correlation process includes the steps of storing a digitally sampled reference signal segment in a first storage device;

storing each of said plurality of digitally sampled broadcast signal segments successively in a second storage device;

successively correlating said stored reference signal segment with each said stored broadcast signal segment to produce said correlation function signal.

3. A process in accordance with claim 2 wherein said reference and broadcast signals are originally in analog form and further wherein said processed reference signal and said processed broadcast signal are derived from the audio signal portions of said reference and broadcast signals.

4. A process for automatic electronic recognition and identification of programs and commercial advertisements broadcast on television and radio, said process comprising the steps of processing a reference signal which constitutes the program or commercial advertisement to be identified in a non-linear manner to produce a non-linear signal;

forming an envelope of said non-linear signal to produce an envelope reference signal;

generating a digitally sampled envelope reference signal segment having a selected sampling rate and time duration, said envelope reference signal segment representing at least a part of said envelope reference signal;

processing a broadcast signal in the same non-linear manner as said reference signal to produce a non-linear signal;

forming an envelope of said non-linear signal to produce an envelope broadcast signal;

generating a plurality of successive digitally sampled envelope broadcast signal segments each having the same sampling rate and time duration as the selected sampling rate and time duration of said envelope reference signal segment;

correlating each successive envelope broadcast signal segment with said envelope reference signal segment to produce a correlation function signal which has a relatively small amplitude level when said correlated signal segments are different and a relatively large amplitude level when said correlated signal segments are the same;

sensing the amplitude level of said correlation function signal to provide a recognition signal when the amplitude of said correlation function signal exceeds a selected threshold level to identify the presence of said program or commercial advertisement in said broadcast signal.

5. A process in accordance with claim 4 wherein said correlation process includes storing said digitally samplEd envelope reference signal segment in a first storage device;

storing each of said digitally sampled envelope broadcast signal segments successively in a second storage device; and

successively correlating said stored envelope reference signal segment with each of said stored envelope broadcast signal segments to produce said correlation function signal.

6. A process in accordance with claim 4 wherein said non-linear processing of said reference signal and said broadcast signal includes rectifying said reference signal and said broadcast signal, respectively.

7. A process in accordance with claim 6 wherein said rectification is a full-wave rectification.

8. A process in accordance with claim 6 wherein said rectification is a half-wave rectification.

9. A process in accordance with claim 4 wherein said non-linear processing of said reference signal and said broadcast signal includes squaring the amplitudes of said reference signal and said broadcast signal, respectively.

10. A process in accordance with claim 4 wherein the envelope signals of said non-linearly processed reference signal and said non-linearly processed broadcast signal are formed by a peak detection process.

11. A process in accordance with claim 4 wherein the envelope signals of said non-linearly processed reference signal and said non-linearly processed broadcast signal are formed by a low-pass filtering process.

12. A process in accordance with claim 4 wherein the frequency components of said envelope reference signal and said envelope broadcast signal are generally below 100 Hz.

13. A process in accordance with claim 5 wherein said envelope reference and envelope broadcast signals are in analog form and further wherein said envelope reference signal segment and said envelope broadcast signal segments are derived from the audio signal portions of said reference and broadcast signals.

14. A process in accordance with claim 5 wherein said envelope reference and envelope broadcast signals are in analog form and further wherein said envelope reference signal segment and said envelope broadcast signal segments are derived from the video signal portions of said reference and broadcast signals.