System for suppressing wind noise

• US 8,165,875 B2
• Filed: 10/12/2010
• Issued: 04/24/2012
• Est. Priority Date: 02/21/2003
• Status: Expired due to Term

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: QNX Software Systems Limited (Canada) (Blackberry Limited)
• Inventors: Hetherington, Phillip A., Li, Xueman, Zakarauskas, Pierre
• Primary Examiner(s): Abebe, Daniel D
• Application Number:
  US12/902,503
• Publication Number:
  US 20110026734A1
• Time in Patent Office: 560 Days
• Field of Search: 704/226, 704/233, 381/94.8
• US Class Current: 704/233
• CPC Class Codes: G10L 21/0208 Noise filtering
• CPC Class Codes: G10L 21/0232 Processing in the frequency domain

Abstract

A voice enhancement logic improves the perceptual quality of a processed voice. The voice enhancement system includes a noise detector and a noise attenuator. The noise detector detects a wind buffet and a continuous noise by modeling the wind buffet. The noise attenuator dampens the wind buffet to improve the intelligibility of an unvoiced, a fully voiced, or a mixed voice segment.

Claims

1. A system for suppressing wind noise, comprising:

a wind noise detector configured to identify whether an input signal contains a wind buffet by fitting a line to at least a portion of the input signal in a signal-to-noise ratio domain; and

a wind noise attenuator electrically connected to the wind noise detector to attenuate the wind buffet in the input signal in response to the wind noise detector identifying that the input signal contains the wind buffet.

2. The system of claim 1, where the wind noise detector is configured to identify whether the input signal contains the wind buffet based on a correlation between the line and the portion of the input signal.

3. The system of claim 1, where the line comprises a straight linear model, and where the wind noise detector is configured to fit the straight linear model to the portion of the input signal through a best-fit linear regression.

4. The system of claim 1, where the wind noise detector is configured to identify whether the input signal contains the wind buffet based on a calculated offset or a y-intercept of the line fit to the portion of the input signal.

5. The system of claim 4, where the wind noise detector is configured to compare the calculated offset or the y-intercept to a predetermined threshold and identify that the input signal contains the wind buffet when the calculated offset or the y-intercept exceeds the predetermined threshold.

6. The system of claim 1, where the wind noise detector is configured to model the line to a portion of a low frequency spectrum of the input signal.

7. The system of claim 1, where the wind noise detector is configured to analyze an average wind buffet model, and where the wind noise detector is configured to derive the average wind buffet model by a weighted average of modeled signals analyzed earlier in time.

8. The system of claim 7, where the wind noise detector is configured to prevent a newly calculated value of a selected attribute of the average wind buffet model from exceeding an average value.

9. The system of claim 7, where the wind noise detector is configured to forgo updating the average wind buffet model when a voiced or a mixed voice signal is detected.

10. The system of claim 1, where the wind noise detector is configured to limit a wind buffet correction when a vowel or a harmonic like structure is detected.

11. The system of claim 1, further comprising a residual attenuator electrically coupled to the wind noise detector and the wind noise attenuator to dampen signal power in a low frequency range when a large increase in a signal power is detected in the low frequency range.

12. The system of claim 1, where the wind noise detector comprises a processor, a non-transitory computer-readable medium, or a circuit.

13. A method of dampening a wind buffet from an input signal, comprising:

fitting a line to at least a portion of the input signal;

detecting, by a wind noise detector that comprises a processor, a non-transitory computer-readable medium, or a circuit, that the input signal contains the wind buffet based on a correlation between the line and the portion of the input signal; and

dampening the wind buffet in the input signal to obtain a noise-reduced signal.

14. The method of claim 13, where the line comprises a straight linear model, and where the act of fitting comprises fitting the straight linear model to the portion of the input signal in a signal-to-noise ratio domain through a best-fit linear regression.

15. The method of claim 13, where the act of detecting comprises applying wind buffet line fitting rules to the line to obtain a constrained line adhering to the wind buffet line fitting rules.

16. A method of dampening a wind buffet from an input signal, comprising:

fitting a line to at least a portion of the input signal;

calculating an offset or a y-intercept of the line fit to the portion of the input signal;

detecting, by a wind noise detector that comprises a processor, a non-transitory computer-readable medium, or a circuit, that the input signal contains the wind buffet based on a comparison between the calculated offset or the y-intercept and a predetermined threshold; and

dampening the wind buffet in the input signal to obtain a noise-reduced signal.

17. The method of claim 16, where the line comprises a straight linear model, and where the act of fitting comprises fitting the straight linear model to the portion of the input signal in a signal-to-noise ratio domain through a best-fit linear regression.

18. The method of claim 16, where the act of detecting comprises:

comparing the calculated offset or the y-intercept to the predetermined threshold; and

identifying that the input signal contains the wind buffet when the calculated offset or the y-intercept exceeds the predetermined threshold.

19. A product, comprising:

a non-transitory computer readable storage medium; and

logic stored on the non-transitory computer readable storage medium for execution by a processor for causing the processor to;

fit a line to at least a portion of an input signal;

detect that the input signal contains a wind buffet based on a correlation between the line and the portion of the input signal; and

dampen the wind buffet in the input signal to obtain a noise-reduced signal.

20. The product of claim 19, where the line comprises a straight linear model, and where the logic for causing the processor to fit the line comprises logic for causing the processor to fit the straight linear model to the portion of the input signal in a signal-to-noise ratio domain through a best-fit linear regression.