Detection of acoustic impulse events in voice applications

• US 10,242,696 B2
• Filed: 10/11/2016
• Issued: 03/26/2019
• Est. Priority Date: 10/11/2016
• Status: Active Grant

• Current Assignee: Cirrus Logic Incorporated
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Ebenezer, Samuel Pon Varma
• Primary Examiner(s): Wozniak, James S
• Application Number:
  US15/290,685
• Publication Number:
  US 20180102135A1
• Time in Patent Office: 896 Days
• Field of Search: 704226-227, 704233
• CPC Class Codes: G10L 2021/02166 Microphone arrays; Beamforming
• CPC Class Codes: G10L 21/02 Speech enhancement, e.g. noise reduction or echo cancellation reducing echo effects in line transmission systems H04B3/20; echo suppression in hands-free telephones H04M9/08
• CPC Class Codes: G10L 21/0232 Processing in the frequency domain
• CPC Class Codes: G10L 25/30 using neural networks
• CPC Class Codes: G10L 25/84 for discriminating voice from noise

Abstract

In accordance with embodiments of the present disclosure, an integrated circuit for implementing at least a portion of an audio device may include an audio output configured to reproduce audio information by generating an audio output signal for communication to at least one transducer of the audio device, a microphone input configured to receive an input signal indicative of ambient sound external to the audio device and a processor configured to implement an impulsive noise detector. The impulsive noise detector may include a sudden onset detector for predicting an occurrence of a signal burst event of the input signal and an impulsive detector for determining whether the signal burst event comprises a speech event or a noise event.

Claims

1. An integrated circuit for implementing at least a portion of an audio device, comprising:

an audio output configured to reproduce audio information by generating an audio output signal for communication to at least one transducer of the audio device;

a microphone input configured to receive an input signal indicative of ambient sound external to the audio device; and

a processor configured to implement an impulsive noise detector comprising;

a sudden onset detector for predicting an occurrence of a signal burst event of the input signal; and

an impulsive detector for determining whether the signal burst event comprises a speech event or a noise event based on whether a threshold minimum of instantaneous noise events are detected within a validation period comprising a selected period of time;

wherein the processor is further configured to implement a latency mitigation module configured to;

freeze state information of state-based processing associated with the audio device during the validation period in response to the sudden onset detector predicting the occurrence of the signal burst event;

during the validation period, perform shadow processing using the frozen state information as shadow state information; and

if the signal burst event is validated as a noise event, unfreeze the state information for use by the state-based processing;

wherein, in response to a determination that the signal burst event comprises a speech event, the integrated circuit is configured to cause the audio device to respond to the speech event by adapting a response of at least one component selected from the group consisting of a noise suppressor component, a background noise estimator component, an adaptive beamformer component, a dynamic beam steering component, an always-on voice detection component, and a conversation-based playback management component.

2. The integrated circuit of claim 1, wherein the processor is further configured to modify a characteristic associated with the audio information in response to detection of a noise event.

3. The integrated circuit of claim 2, wherein the characteristic comprises one or more of an amplitude of the audio information and spectral content of the audio information.

4. The integrated circuit of claim 2, wherein the characteristic comprises at least one coefficient of a voice-based processing algorithm including at least one of a noise suppressor, a background noise estimator, an adaptive beamformer, dynamic beam steering, always-on voice detection, and a conversation-based playback management system.

5. The integrated circuit of claim 1, wherein the impulsive detector is configured to evaluate harmonicity, sparsity, and degree of temporal modulation of a signal spectrum of the input signal to determine whether the signal burst event comprises a speech event or a noise event.

6. The integrated circuit of claim 1, wherein the latency mitigation module is further configured to:

if the signal burst event is not validated as a noise event, at the end of the validation period, cause the state-based processing to use the shadow state information as modified by the shadow processing as the state information.

7. An impulsive noise detection system comprising a processor configured to:

receive an input signal indicative of ambient sound external to an audio device;

predict an occurrence of a signal burst event of the input signal;

determine whether the signal burst event comprises a speech event or a noise event based on whether a threshold minimum of instantaneous noise events are detected within a validation period comprising a selected period of time;

freeze state information of state-based processing during the validation period in response to the predicted occurrence of the signal burst event;

during the validation period, perform shadow processing using the frozen state information as shadow state information;

in response to a determination that the signal burst event comprises a noise event, unfreeze the state information for use by the state-based processing; and

in response to a determination that the signal burst event comprises a speech event, cause the audio device to respond to the speech event by adapting a response of at least one component selected from the group consisting of a noise suppressor component, a background noise estimator component, an adaptive beamformer component, a dynamic beam steering component, an always-on voice detection component, and a conversation-based playback management component.

8. The system of claim 7, wherein the processor is further configured to modify a characteristic associated with audio information reproduced by the audio device in response to detection of a noise event.

9. The system of claim 8, wherein the characteristic comprises one or more of an amplitude of the audio information and spectral content of the audio information.

10. The system of claim 8, wherein the characteristic comprises at least one coefficient of a voice-based processing algorithm including at least one of a noise suppressor, a background noise estimator, an adaptive beamformer, dynamic beam steering, always-on voice detection, and a conversation-based playback management system.

11. The system of claim 7, wherein determining whether the signal burst event comprises a speech event or a noise event comprises evaluating harmonicity, sparsity, and degree of temporal modulation of a signal spectrum of the input signal to determine whether the signal burst event comprises a speech event or a noise event.

12. The system of claim 7, wherein the processor is further configured to:

if the signal burst event is not validated as a noise event, at the end of the validation period, cause the state-based processing to use the shadow state information as modified by the shadow processing as the state information.