System for suppressing passing tire hiss

• US 8,027,833 B2
• Filed: 05/09/2005
• Issued: 09/27/2011
• Est. Priority Date: 05/09/2005
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: QNX Software Systems Company (Blackberry Limited)
• Inventors: Paranjpe, Shreyas A., Hetherington, Phillip A.
• Primary Examiner(s): Jackson; Jakieda R
• Application Number:
  US11/125,052
• Publication Number:
  US 20060251268A1
• Time in Patent Office: 2,332 Days
• Field of Search: 704/227
• US Class Current: 704/226
• CPC Class Codes: G10L 21/0208 Noise filtering

Abstract

A voice enhancement logic improves the perceptual quality of a processed voice. The voice enhancement system includes a passing tire hiss noise detector and a passing tire hiss noise attenuator. The passing tire hiss noise detector detects a passing tire hiss noise by modeling the passing tire hiss. The passing tire hiss noise attenuator dampens the passing tire hiss noise to improve the intelligibility of a speech signal.

Claims

1. A system for suppressing passing tire hiss noise from a signal, comprising:

a noise detector that detects and models a passing tire hiss from an input signal; and

a noise attenuator electrically connected to the noise detector to attenuate at least a portion of the passing tire hiss from the input signal;

where the noise detector is configured to identify whether the input signal includes the passing tire hiss by fitting a smoothly varying function to a portion of the input signal.

2. The system of claim 1 where the noise detector is configured to identify whether the input signal includes passing tire hiss by fitting a Lorentzian function to a portion of the input signal in a time domain.

3. The system of claim 1 where the noise detector is configured to model the passing tire hiss by fitting the smoothly varying function to the input signal in a time-frequency domain.

4. The system of claim 1 where the noise detector is configured to constrain a passing tire hiss adaptation when a structure similar to a vowel or a harmonic like structure is detected.

5. The system of claim 1 where the noise detector is configured to receive information from an automotive bus and to selectively constrain a passing tire hiss adaptation based on the information received from the automotive bus.

6. The system of claim 5 where the noise detector is configured to receive information from the automotive bus about whether widows of a vehicle are open or closed, and where the noise detector is configured to disable or constrain passing tire hiss noise detection when the windows are closed.

7. The system of claim 1 where the noise detector is configured to derive an average passing tire hiss model, and the average passing tire hiss model is not updated near a speech or speech plus noise signal.

8. The system of claim 1 where the noise detector is configured to derive an average passing tire hiss model that is derived by a combination of other modeled signals analyzed earlier in time.

9. The system of claim 1 where the noise detector is configured to derive an average passing tire hiss model that is derived by a weighted average of other modeled signals analyzed earlier in time.

10. The system of claim 1 where the noise attenuator is configured to substantially remove the passing tire hiss and a continuous noise from the input signal.

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

12. The system of claim 1 further including an input device electrically coupled to the noise detector, the input device configured to convert sound waves into analog signals.

13. The system of claim 1 further including a pre-processing system coupled to the noise detector, the pre-processing system configured to pre-condition the input signal before the input signal is processed by the noise detector.

14. The system of claim 13 where the pre-processing system comprises a first microphone and a second microphone spaced apart and configured to exploit a lag time of a signal that may arrive at the first microphone or the second microphone.

15. The system of claim 14 further comprising a controller that automatically selects the first microphone or the second microphone and a channel that senses the least amount of noise in the input signal.

16. The system of claim 1 where the noise detector is configured to detect occurrence of passing tire hiss in the input signal based on a correlation between the smoothly varying function and an envelope of the input signal in the time domain over one or more frequency bands of the input signal.

17. The system of claim 1 where the smoothly varying function comprises a log-Lorentzian function, with a width determined by a speed of a passing vehicle generating the passing tire hiss, and a sharpness determined by a lateral distance of the passing vehicle from a receiver that received the input signal.

18. The system of claim 1 where the noise detector is configured to separate noise-like segments of the input signal from remaining portions of the input signal, and where the noise detector is configured to analyze the noise-like segments to identify whether the noise-like segments include passing tire hiss noise.

19. The system of claim 18 where the noise detector is configured to derive a passing tire hiss model when the noise-like segments include passing tire hiss noise, where the noise detector is configured to store the passing tire hiss model in memory, and where the noise attenuator is configured to use the passing tire hiss model stored in memory to remove passing tire hiss from the input signal.

20. The system of claim 1 where the noise detector comprises a processor configured to run logic to detect the passing tire hiss from the input signal.

21. A system for detecting passing tire hiss noise from a signal, comprising:

a time frequency transform logic that converts a time varying input signal into the frequency domain;

a background noise estimator coupled to the time frequency transform logic, the background noise estimator configured to measure a continuous noise that occurs near a receiver; and

a passing tire hiss noise detector coupled to the background noise estimator, the passing tire hiss noise detector configured to automatically identify and model a noise associated with passing tire hiss;

where the passing tire hiss noise detector is configured to identify whether the input signal includes the noise associated with passing tire hiss based on a correlation between a smoothly varying function and a portion of the input signal.

22. The system of claim 21 further comprising a transient detector configured to disable the background noise estimator when a transient signal is detected.

23. The system of claim 21 where the passing tire hiss noise detector is configured to identify that the noise is associated with passing tire hiss based on the correlation between the smoothly varying function and the portion of the input signal.

24. The system of claim 23 wherein the smoothly varying function is a Lorentzian function.

25. The system of claim 21 further comprising a signal discriminator coupled to the passing tire hiss noise detector, the signal discriminator configured to mark the voice and the noise segments of the input signal.

26. The system of claim 21 further comprising a passing tire hiss noise attenuator coupled to the passing tire hiss noise detector, the passing tire hiss noise attenuator configured to reduce the noise associated with the passing tire hiss that is sensed by the receiver.

27. The system of claim 26 where the noise attenuator is configured to substantially remove the noise associated with the passing tire hiss from the input signal.

28. The system of claim 21 further comprising a residual attenuator coupled to the background noise estimator operable to dampen signal power in a mid to high frequency range when a large increase in signal power is detected in the mid to high frequency range.

29. The system of claim 21 where passing tire hiss noise detector comprises a processor configured to run logic to identify the noise associated with passing tire hiss.

30. A system for suppressing passing tire hiss noise from a signal, comprising:

a time frequency transform logic that converts a time varying input signal into the frequency domain;

a background noise estimator coupled to the time frequency transform logic, the background noise estimator configured to measure a continuous noise that occurs near a receiver;

a passing tire hiss noise detector coupled to the background noise estimator, the passing tire hiss noise detector configured to fit a smoothly varying function to a portion of an input signal, where the passing tire hiss noise detector is configured to identify whether the input signal includes passing tire hiss based on a correlation between the smoothly varying function and the portion of the input signal; and

a passing tire hiss noise attenuator coupled to the passing tire hiss noise detector, the passing tire hiss noise attenuator being configured to remove a noise associated with passing tire hiss that is sensed by the receiver.

31. The system of claim 30 where the passing tire hiss noise detector is configured to detect occurrence of passing tire hiss in the input signal based on a correlation between the smoothly varying function and an envelope of the input signal in the time domain over one or more frequency bands of the input signal.

32. A method of removing passing tire hiss from a signal comprising:

converting a time varying signal to a complex spectrum;

estimating a background noise;

detecting a passing tire hiss noise based on a correlation between a smoothly varying function and a portion of an input signal; and

dampening the passing tire hiss noise from the input signal.

33. The method of claim 32 where the act of estimating the background noise comprises estimating the background noise when a transient is not detected.

34. The method of claim 32 where the act of dampening the passing tire hiss noise comprises substantially removing the passing tire hiss noise from the input signal.

35. The method of claim 32 where the act of detecting the passing tire hiss noise comprises detecting occurrence of the passing tire hiss noise in the input signal based on the correlation between the smoothly varying function and an envelope of the input signal in the time domain over one or more frequency bands of the input signal.

36. The method of claim 32 where the act of detecting the passing tire hiss noise comprises detecting the passing tire hiss noise by a processor configured to run logic to detect the passing tire hiss noise from the input signal.

37. A method of removing passing tire hiss from a signal comprising:

converting a time varying signal to a complex spectrum;

estimating a background noise;

detecting a passing tire hiss noise when a high correlation exists between a smoothly varying function and a portion of an input signal; and

removing the passing tire hiss noise from the input signal.

38. A computer-readable non-transitory medium storing software that, when executed by a computer, causes the computer to control a detection of a noise associated with a passing tire hiss, the software comprising:

a detector logic that processes electrical signals that represent sound waves;

a spectral conversion logic that converts the electrical signals from a first domain to a second domain; and

a signal analysis logic that models a portion of the sound waves that are associated with the passing tire hiss;

where the signal analysis logic identifies that the portion of the sound waves contains passing tire hiss based on a correlation between a smoothly varying function and the portion of the sound waves.

39. The computer-readable medium of claim 38 further comprising logic that derives a portion of a speech signal masked by the noise.

40. The computer-readable medium of claim 38 further comprising logic that attenuates portion of the sound waves.

41. The computer-readable medium of claim 38 further comprising attenuator logic operable to limit a power in a mid to high frequency range.

42. The computer-readable medium of claim 38 further comprising noise estimation logic that measures a continuous or ambient noise sensed by the detector.

43. The computer-readable medium of claim 42 further comprising transient logic that disables the estimation logic when an increase in power is detected.

44. The computer-readable medium of claim 38 where the signal analysis logic is coupled to a vehicle.

45. The computer-readable medium of claim 38 where the signal analysis logic is coupled to an audio system.

46. The computer-readable medium of claim 38 where the signal analysis logic models only the sound waves that are associated with the passing tire hiss.

47. A system for suppressing passing tire hiss noise from a signal, comprising:

noise detecting means for detecting and modeling a passing tire hiss from an input signal; and

noise attenuating means electrically connected to the noise detecting means for attenuating at least a portion of the passing tire hiss from the input signal;

where the noise detecting means is configured to identify whether the input signal includes the passing tire hiss by a processor fitting a smoothly varying function to a portion of the input signal.

48. The system of claim 47 where the noise detecting means is configured to identify whether the input signal includes passing tire hiss by fitting a Lorentzian function to a portion of the input signal in a time domain.

49. The system of claim 47 where the noise detecting means is configured to model the passing tire hiss by fitting the smoothly varying function to the input signal in a time-frequency domain.

50. The system of claim 47 where the noise detecting means is configured to constrain a passing tire hiss adaptation when a structure similar to a vowel or a harmonic like structure is detected.

51. The system of claim 47 where the noise detecting means is configured to receive information from an automotive bus and to selectively constrain a passing tire hiss adaptation based on the information received from the automotive bus.

52. The system of claim 47 where the noise detecting means is configured to derive an average passing tire hiss model, and the average passing tire hiss model is not updated near a speech or speech plus noise signal.

53. The system of claim 47 where the noise detecting means is configured to derive an average passing tire hiss model that is derived by a combination of other modeled signals analyzed earlier in time.

54. The system of claim 47 where the noise detecting means is configured to derive an average passing tire hiss model that is derived by a weighted average of other modeled signals analyzed earlier in time.

55. The system of claim 47 where the noise attenuating means is configured to substantially dampen the passing tire hiss and a continuous noise from the input signal.

56. The system of claim 47 further comprising residual attenuating means electrically coupled to the noise detecting means and the noise attenuating means for dampening signal power in a mid to high frequency range when a large increase in a signal power is detected in the mid to high frequency range.

57. The system of claim 47 further including input means electrically coupled to the noise detecting means for converting sound waves into analog signals.

58. The system of claim 47 further including pre-processing means coupled to the noise detecting means for pre-conditioning the input signal before the input signal is processed by the noise detecting means.

59. The system of claim 58 where the pre-processing means comprises first and second input means spaced apart and configured to exploit a lag time of a signal that may arrive at the different input means.

60. The system of claim 59 further comprising control means for automatically selecting an input means and a channel that senses the least amount of noise in the input signal.