Circuit arrangement and method for audio signals containing speech

• US 20060080089A1
• Filed: 10/11/2005
• Published: 04/13/2006
• Est. Priority Date: 10/08/2004
• Status: Active Grant

• Current Assignee: Entropic Communications Incorporated (Maxlinear Incorporated)
• Original Assignee: Trident Microsystems Limited (Avnet Incorporated)
• Inventors: Mueller, Stefan, Vierthaler, Matthias, Luecking, Dieter, Pfister, Florian
• Granted Patent: US 8,005,672 B2
• Time in Patent Office: Days
• US Class Current: 704/208
• CPC Class Codes: G10L 21/0364 for improving intelligibility

Abstract

An audio processing system includes a speech detector that receives and processes an audio input signal to determine if the input signal includes components indicative of speech, and provides a control signal indicative of whether or not the audio input signal includes speech. A speech processing device receives the audio input signal and processes the audio input signal to improve its quality if the control signal indicates that the audio input signal includes speech.

Claims

1. Circuit arrangement for improving the intelligibility of audio signal that may contain speech (px), comprising:

a speech detector that detects speech in the audio signal and provides a control signal to control a speech processing device that processes the audio signal.

2. The circuit arrangement of claim 1, where the speech detector is configured and/or controlled to detect speech components in the audio signal.

3. The circuit arrangement of claim 1, where the speech detector compares a range of detected speech components to a threshold value and outputs the control signal depending on the result of the comparison.

4. The circuit arrangement of claim 3, where the speech detector has a control input for entering at least one parameter (V) for variable controlling of the detection in regard to a range of speech components (PX) being detected and/or in regard to a frequency range of speech components (PX) being detected.

5. The circuit arrangement of claim 1, where the speech detector comprises a correlation device (CR) that performs a cross correlation or an autocorrelation of the audio signal or components of the audio signal.

6. The circuit arrangement of claim 1, where the speech detector is configured to process a multi-component audio signal (I), especially a stereo audio signal (L′

, R′

), a 3D stereo audio signal (L, R, C), and/or surround audio signal (L, R, C, S), with several audio signal components (L, R, C, S) and has a processing device (CR) for detection of speech by comparison or a processing the components (L, R, C, S) among each other.

7. The circuit arrangement of claim 6, where the speech detector comprises a direction determining device for determining a direction and/or distance of common signal components of the different components (L, R, C, S).

8. The circuit arrangement of claim 1, where the speech detector comprises a frequency-energy detector (Ef) for determining signal energy in a voice frequency range in relation to signal energy of the audio signal (i).

9. The circuit arrangement of claim 8, where the speech detector is configured and/or controlled to output the control signal depending on results of both a frequency-energy detector (Ef) and a correlation device (CR), a comparison device, and/or a direction determining device.

10. The circuit arrangement of claim 1, where the control signal is configured and/or controlled to activate or deactivate the speech improvement device depending on the speech content of the audio signal.

20. The circuit arrangement of claim 10, where a frequency response is determined by a Finite Impulse Response (FIR) filter or Infinite Impulse Response (IIR) filter.

21. The circuit arrangement of claim 10, where signal components of the audio signal are separated by a matrix.

22. The circuit arrangement of claim 10, where matrix coefficients for a matrix (MX) are determined via a function (P=F(PX)) dependent on the speech component (PX).

23. The circuit arrangement of claim 22, wherein the function (P=F(PX)) is linear and constant.

24. The circuit arrangement of claim 22, wherein the function (P=F(PX)) has a hysteresis.

11. A method for processing audio signals (I) possibly containing speech, where speech or speech components are detected in an audio signal (I) and a control signal (S) is generated and provided to control a speech processing device based upon the outcome of the detection.

12. The method of claim 11, where the control signal (S) is generated depending on the range of detected speech components (PX).

13. The method of claim 12, where the range of detected speech components (PX) is compared to a threshold value (V).

14. The method of claim 13, where the detection is carried out with regard to a range of speech components to be detected and/or with regard to a frequency range of the speech components to be detected (PX) and is adjustable by at least one variable parameter (V).

15. The method of claim 14, where a cross correlation or autocorrelation of the audio signal (I) or components (R, L, C, S) of the audio signal (I) is performed.

16. The method of claim 15, where the audio signal components of a multi-component audio signal with several audio signal components (R, L, C, S) are compared to each other or processed with each other for detection of the speech.

17. The method of claim 16, where the audio signal components (R, L, C, S) are compared or processed with respect to common speech components in the different audio signal components, especially to determine a direction and/or distance of the common signal components.

18. The method of claim 17, where energy of the audio signal (I) is determined within a voice frequency range (f1, . . . , f2) in relation to energy of the audio signal (I) in a different frequency range.

19. The method of claim 18, where the control signal (S) is provided to activate or deactivate the speech improvement device.

25. An audio processing system, comprising:

a speech detector that receives and processes an audio input signal to determine if the input signal includes components indicative of speech, and provides a control signal indicative of whether or not the audio input signal includes speech; and

a speech processing device that receives the audio input signal and processes the audio input signal to improve its quality if the control signal indicates that the audio input signal includes speech.