Voice capture processing modified by back end audio processing state

Patent metadata

Field	Value
Publication number	US-10720173-B2
Application number	US-201815901148-A
Country	US
Kind code	B2
Filing date	Feb 21, 2018
Priority date	Feb 21, 2018
Publication date	Jul 21, 2020
Grant date	Jul 21, 2020

Abstract

Audio systems and methods are provided that receive a playback signal and produce an acoustic signal based upon the playback signal, and include microphone signal(s) for capturing and processing user voice signals. An echo reference signal is based upon the playback signal, and an echo canceler reduces echo components from the microphone signal(s). Functionality of the echo canceler is modified, such as by freezing an adaptive filter, in response to a non-linear condition in the audio playback, or a likelihood of such a non-linear condition.

First claim

What is claimed is:

1. An audio system, comprising:
a microphone to provide a microphone signal;
an echo canceller configured to process the microphone signal based upon an echo reference signal to reduce echo components;
an audio input to receive a playback signal;
a playback section having a processor configured to perform non-linear processing on the playback signal, to provide to the echo canceller a notification that the non-linear processing is enabled by the playback section, and to provide the echo reference signal based upon the playback signal, the playback section further configured to provide a driver signal; and
a transducer configured to convert the driver signal into an acoustic signal;
wherein the notification comprises a plurality of flags sent by the playback section to the echo canceller, wherein each flag in the plurality of flags corresponds to a respective frequency band in a plurality of frequency bands.

2. The audio system of claim 1 wherein the echo canceller is configured to make an operational adjustment in response to the non-linear condition.

3. The audio system of claim 1 wherein the echo canceller is configured to freeze adaptation of an adaptive filter in response to the non-linear condition.

4. The audio system of claim 1 wherein the echo canceller is configured to freeze adaptation of an adaptive filter in response to receiving the flags.

5. The audio system of claim 1 wherein the processor includes a detector coupled to at least one of the transducer or the playback section to determine the non-linear condition.

6. The audio system of claim 1 , wherein each flag in the plurality of flags corresponds to a respective adaptive filter in a plurality of adaptive filters.

7. The audio system of claim 1 , wherein each flag in the plurality of flags corresponds to a respective non-linear condition in a plurality of non-linear conditions.

8. A method of picking up a user's voice in an acoustic environment, the method comprising:
receiving a playback signal;
producing an acoustic signal based on the playback signal;
providing an echo reference signal based on the playback signal;
filtering, by an adaptive filter, the echo reference signal to provide an estimated echo signal;
performing, by a playback section of an audio system, non-linear processing on the playback signal;
providing, by the playback section, a notification that non-linear processing of the playback signal is enabled, wherein the notification comprises a plurality of flags sent by the playback section, wherein each flag in the plurality of flags corresponds to a respective frequency band in a plurality of frequency bands;
freezing an adaptation of the adaptive filter in response to the notification of the non-linear processing;
receiving a microphone signal; and
reducing echo content of the microphone signal based on the estimated echo signal, to provide a pickup signal.

9. The method of claim 8 wherein determining a non-linear condition includes determining that a likelihood of the non-linear condition meets a threshold.

10. The method of claim 8 wherein providing the indication of the non-linear condition includes providing an indication that a signal level is being limited.

11. The method of claim 8 further comprising providing the pickup signal to a processor.

12. The method of claim 11 further comprising analyzing the pickup signal, by the processor, to detect a spoken word.

13. The method of claim 12 further comprising, in response to detecting the spoken word, analyzing the pickup signal, by the processor, to detect a user command and executing an algorithm in response to detecting the user command.

14. An audio system, comprising:
a microphone to provide a microphone signal;
an echo canceller configured to process the microphone signal based upon an echo reference signal to reduce echo components;
an audio input to receive a playback signal;
a playback section having a processor configured to perform non-linear processing on the playback signal, to provide to the echo canceller a notification that the non-linear processing is enabled by the playback section, and to provide the echo reference signal based upon the playback signal, the playback section further configured to provide a driver signal; and
a transducer configured to convert the driver signal into an acoustic signal;
wherein the notification comprises a plurality of flags sent by the playback section to the echo canceller, wherein each flag in the plurality of flags corresponds to a respective adaptive filter in a plurality of adaptive filters.

15. The audio system of claim 14 wherein the echo canceller is configured to make an operational adjustment in response to the non-linear condition.

16. The audio system of claim 14 wherein the echo canceller is configured to freeze adaptation of an adaptive filter that has received the corresponding flag in response to the non-linear condition.

17. The audio system of claim 14 wherein the echo canceller is configured to freeze adaptation of an adaptive filter in response to receiving the corresponding flag.

18. The audio system of claim 14 wherein the processor includes a detector coupled to at least one of the transducer or the playback section to determine the non-linear condition.

Assignees

• Bose Corp

Inventors

• Freeman Eric J
• Gaalaas Joseph

Classifications

• G10L21/0208 Primary

  Noise filtering · CPC title

• G10L2021/02082

  the noise being echo, reverberation of the speech · CPC title

• H04R1/406

  microphones · CPC title

• G10L15/22

  Procedures used during a speech recognition process, e.g. man-machine dialogue · CPC title

• G10L25/78

  Detection of presence or absence of voice signals (switching of direction of transmission by voice frequency in two-way loud-speaking telephone systems H04M9/10) · CPC title