Signal processing apparatus and method, recording medium, and program

• US 20030091323A1
• Filed: 07/12/2002
• Published: 05/15/2003
• Est. Priority Date: 07/17/2001
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nishiguchi, Masayuki, Abe, Mototsugu
• Granted Patent: US 6,934,462 B2
• Time in Patent Office: Days
• US Class Current: 386/285
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 2220/2525 Magneto-optical [MO] discs
• CPC Class Codes: G11B 2220/90 Tape-like record carriers
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: G11B 27/107 of operating tapes
• CPC Class Codes: G11B 27/28 by using information signals recorded by the same method as the main recording G11B27/22 takes precedence
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/43072 of multiple content streams on the same device
• CPC Class Codes: H04N 21/4334 Recording operations recording of a television signal H04N5/76; arrangements for recording or accumulating broadcast information or broadcast-related information H04H60/27
• CPC Class Codes: H04N 21/4394 involving operations for analysing the audio stream, e.g. detecting features or characteristics in audio streams arrangements characterised by components specially adapted for monitoring, identification or recognition of audio in broadcast systems H04H60/58
• CPC Class Codes: H04N 21/44008 involving operations for analysing video streams, e.g. detecting features or characteristics in the video stream arrangements characterised by components specially adapted for monitoring, identification or recognition of video in broadcast systems H04H60/59
• CPC Class Codes: H04N 21/812 involving advertisement data advertising per se G06Q30/02
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments
• CPC Class Codes: H04N 5/04 Synchronising for television systems using pulse code modulation H04N7/56
• CPC Class Codes: H04N 5/147 Scene change detection
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 5/9201 involving the multiplexing of an additional signal and the video signal

Abstract

For accurate scene-change detection, the amplitudes of sub-band signals subjected to the spectral decomposition are detected, and the detected amplitudes are smoothed and sampled during smoothing. Then, the amount of spectral change is determined based on the smoothed sub-band amplitude and the smoothed sub-band amplitude which is one sampled amplitude before that smoothed sub-band amplitude. It is then determined whether or not the determined amount of spectral change is greater than a predetermined threshold, and processing is performed based on the determination result.

Claims

1. A signal processing apparatus comprising:

amplitude extraction means for extracting the amplitude of an input audio signal, the audio signal having a plurality of contents in a time-division manner; and

change-point detection means for detecting a change point of content in the input audio signal based on the temporal change of the amplitude extracted by said amplitude extraction means.

2. A signal processing apparatus according to claim 1, wherein said amplitude extraction means divides the input audio signal into spectral signals, and extracts the amplitude of the spectral signals.

3. A signal processing apparatus according to claim 1, wherein said amplitude extraction means divides the input audio signal into sub bands, and extracts the amplitude for each of the divided sub bands.

4. A signal processing apparatus according to claim 1, wherein said change-point detection means smoothes out the extracted amplitude for use.

5. A signal processing apparatus according to claim 1, wherein said change-point detection means determines the amount of energy change using the amplitude, and detects a change point of content in the input audio signal based on the amount of energy change.

6. A signal processing apparatus according to claim 1, wherein the input audio signal is frequency resolved and encoded together with a scaling factor, and said amplitude extraction means extracts the scaling factor as the amplitude.

7. A signal processing method comprising:

an amplitude extracting step of extracting the amplitude of an input audio signal, the audio signal having a plurality of contents in a time-division manner; and

a change-point detecting step of detecting a change point of content in the input audio signal based on the temporal change of the amplitude extracted in said amplitude extracting step.

8. A recording medium having a computer-readable program recorded thereon, the program comprising:

an amplitude extracting step of extracting the amplitude of an input audio signal, the audio signal having a plurality of contents in a time-division manner; and

a change-point detecting step of detecting a change point of content in the input audio signal based on the temporal change of the amplitude extracted in said amplitude extracting step.

9. A program which causes a computer to execute a process comprising:

an amplitude extracting step of extracting the amplitude of an input audio signal, the audio signal having a plurality of contents in a time-division manner; and

a change-point detecting step of detecting a change point of content in the input audio signal based on the temporal change of the amplitude extracted in said amplitude extracting step.

10. A signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the apparatus comprising;

audio signal change-point detection means for extracting the amplitude of the input audio signal, and for detecting a change point of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein video and audio in the vicinity of the detected change point are played back or recorded.

11. A signal processing apparatus according to claim 10, wherein the audio and video signals comprise a television broadcast signal, and the played or recorded video and audio comprise a commercial message.

12. A signal processing method for a signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the method comprising:

an audio signal change-point detecting step of extracting the amplitude of the input audio signal in order to detect a change point of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein video and audio in the vicinity of the detected change point are played back or recorded.

13. A recording medium having recorded thereon a computer-readable program for a signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the program comprising:

an audio signal change-point detecting step of extracting the amplitude of the input audio signal in order to detect a change point of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein video and audio in the vicinity of the detected change point are played back or recorded.

14. A program for a signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the program performing a computer-executable process comprising:

an audio signal change-point detecting step of extracting the amplitude of the input audio signal in order to detect a change point of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein video and audio in the vicinity of the detected change point are played back or recorded.

15. A signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the apparatus comprising:

video signal change-point detection means for detecting change points of content in the input video signal; and

audio signal change-point detection means for extracting the amplitude of the input audio signal and for detecting change points of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein a signal for predetermined content is detected based on a time interval between the detected change points of content in the input audio signal and between the detected change points of content in the input video signal.

16. A signal processing apparatus according to claim 15, wherein the audio and video signals comprise a television broadcast signal, and the predetermined content comprise a commercial message.

17. A signal processing method for a signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the method comprising:

a video signal change-point detecting step of detecting change points of content in the input video signal; and

an audio signal change-point detecting step of extracting the amplitude of the input audio signal in order to detect change points of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein a signal for predetermined content is detected based on a time interval between the detected change points of content in the input audio signal and between the detected change points of content in the input video signal.

18. A recording medium having recorded thereon a computer-readable program for a signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the program comprising:

a video signal change-point detecting step of detecting change points of content in the input video signal; and

an audio signal change-point detecting step of extracting the amplitude of the input audio signal in order to detect change points of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein a signal for predetermined content is detected based on a time interval between the detected change points of content in the input audio signal and between the detected change points of content in the input video signal.

19. A program for a signal processing apparatus to which audio and video signals are input, the audio and video signals having a plurality of contents in a time-division manner, the program performing a computer-executable process comprising:

a video signal change-point detecting step of detecting change points of content in the input video signal; and

an audio signal change-point detecting step of extracting the amplitude of the input audio signal in order to detect change points of content in the input audio signal based on the temporal change of the extracted amplitude,

wherein a signal for predetermined content is detected based on a time interval between the detected change points of content in the input audio signal and between the detected change points of content in the input video signal.