Noise-reduction processing method and device, and earphones

Patent metadata

Field	Value
Publication number	US-11328705-B2
Application number	US-201815733648-A
Country	US
Kind code	B2
Filing date	Aug 14, 2018
Priority date	May 4, 2018
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

A method and device for noise-reduction processing and an earphone are disclosed. The method includes: collecting an environmental-sound signal by using a feedforward microphone to acquire amplitude information and spectrum information of the environmental-sound signal; performing feedforward noise-reduction processing on the environmental-sound signal according to the amplitude information of the environmental-sound signal, and extracting a sound signal having a specified frequency in the environmental-sound signal according to the spectrum information of the environmental-sound signal; and outputting the sound signal having the specified frequency together with the signal after being feedforward noise-reduction processed. The present disclosure can realize the monitoring of the valuable sound signal having a specified frequency in the environmental-sound signal.

First claim

What is claimed is:

1. A method for noise-reduction processing, comprising:
collecting an environmental-sound signal by using a feedforward microphone to acquire amplitude information and spectrum information of the environmental-sound signal;
performing feedforward noise-reduction processing on the environmental-sound signal according to the amplitude information of the environmental-sound signal, and extracting a sound signal having a specified frequency in the environmental-sound signal according to the spectrum information of the environmental-sound signal;
outputting the sound signal having the specified frequency together with a signal after being feedforward noise-reduction processed; and
wherein after acquiring the amplitude information of the environmental-sound signal, the method further comprises:
acquiring energy information of the environmental-sound signal at each sampling time point according to the amplitude information of the environmental-sound signal, wherein energy information of the environmental-sound signal corresponding to a current nth sampling time point is P(n), and energy information of the environmental-sound signal corresponding to an (n−1)th sampling time point is P(n−1).

2. The method according to claim 1 , wherein after extracting a sound signal having a specified frequency in the environmental-sound signal, and before outputting the sound signal having the specified frequency together with the signal after being feedforward noise-reduction processed, the method further comprises:
performing gain processing on the sound signal having the specified frequency according to the amplitude information of the environmental-sound signal; and
adjusting an amplitude value of the sound signal having the specified frequency after being gain processed to a preset amplitude range.

3. The method according to claim 2 , wherein the step of performing gain processing on the sound signal having the specified frequency comprises:
if the P(n) is not greater than a first preset energy threshold, adjusting a current gain value A(n) to an initial gain value A(0);
if the P(n) is greater than the first preset energy threshold, and the P(n)/P(n−1) is greater than a first energy-ratio threshold, or, the P(n)/P(n−1) is less than a second energy-ratio threshold, adjusting the current gain value A(n) to be less than the initial gain value A(0) by one gain value; and
if the P(n) is greater than the first preset energy threshold, and the P(n)/P(n−1) is between the first energy-ratio threshold and the second energy-ratio threshold, adjusting the current gain value A(n) to be between the initial gain value A(0) and a gain obtained by subtracting the gain value from the initial gain value A(0);
wherein the gain value is obtained by performing a logarithm operation on a difference between the P(n) and the first preset energy threshold.

4. The method according to claim 3 , wherein the step of adjusting the current gain value A(n) to be between the initial gain value A(0) and a gain obtained by subtracting the gain value from the initial gain value A(0) comprises:
starting from a current sampling time point, adjusting the current gain value A(n) to attenuate from the initial gain value A(0) at an attenuation speed;
in the attenuation process, corresponding to an (n+m)th sampling time point of the environmental-sound signal, energy information is P(n+m) and gain value is A(n+m), if the energy information P(n+m) is less than the first preset energy threshold, making the gain value A(n+m) restore to the initial gain value A(0) at a growth speed; and
while the gain value A(n+m) is restoring to the initial gain value A(0) at the growth speed, if the P(n+m) is greater than the first preset energy threshold, making the gain value A(n+m) attenuate again at the attenuation speed;
wherein the attenuation speed is a ratio of a value obtained by performing logarithm operation on a difference between the P(n+m) and the first preset energy threshold to a first preset time period;
the growth speed is a ratio of a value obtained by performing logarithm operation on a difference between the P(n+m) and the first preset energy threshold to a second preset time period;
a value of the attenuation speed is adjusted by adjusting a length of the first preset time period; and
a value of the growth speed is adjusted by adjusting a length of the second preset time period.

5. The method according to claim 2 , wherein the step of performing feedforward noise-reduction processing on the environmental-sound signal comprises: if the P(n) is less than a second preset energy threshold, controlling a current feedforward noise-reduction coefficient to be set to 0; if the P(n) is greater than a third preset energy threshold, controlling a current feedforward noise-reduction coefficient to remain unchanged; and if the P(n) is between the second preset energy threshold and the third preset energy threshold, controlling a current feedforward noise-reduction coefficient to be reduced by one noise-reduction-coefficient preset value; wherein the second preset energy threshold is less than the third preset energy threshold.

6. The method according to claim 1 , further comprising:
determining a current scene mode at a preset time interval according to the spectrum information of the environmental-sound signal;
acquiring a feedback noise-reduction coefficient corresponding to the current scene mode; and
performing feedback noise-reduction processing on an environmental-sound signal collected by a feedback microphone according to the feedback noise-reduction coefficient, and outputting a signal after being feedback noise-reduction processed.

7. An earphone, comprising a feedforward microphone, a feedback microphone and a speaker, wherein the earphone comprises a memory and a processor, the memory stores a computer program executable by the processor, and when the computer program is executed by the processor, a method for noise-reduction processing is implemented, and the method comprising:
collecting an environmental-sound signal by using the feedforward microphone to acquire amplitude information and spectrum information of the environmental-sound signal;
performing feedforward noise-reduction processing on the environmental-sound signal according to the amplitude information of the environmental-sound signal, and extracting a sound signal having a specified frequency in the environmental-sound signal according to the spectrum information of the environmental-sound signal;
outputting the sound signal having the specified frequency together with a signal after being feedforward noise-reduction processed; and
wherein after acquiring the amplitude information of the environmental-sound signal, the method further comprises: acquiring energy information of the environmental-sound signal at each sampling time point according to the amplitude information of the environmental-sound signal, wherein energy information of the environmental-sound signal corresponding to a current n th sampling time point is P(n), and energy information of the environmental-sound signal corresponding to an (n−1) th sampling time point is P(n−1).

8. The earphone according to claim 7 ,
wherein after extracting a sound signal having a specified frequency in the environmental-sound signal, and before outputting the sound signal having the specified frequency together with the signal after being feedforward noise-reduction processed, the method further comprises:
performing gain processing on the sound signal having the specified frequency according to the amplitude information of the environmental-sound signal; and
adjusting an amplitude value of the sound signal having the specified frequency after being gain pr

Assignees

• Goertek Tech Co Ltd

Inventors

• Hua Yang
• Li Peng

Classifications

• G10L21/0208 Primary

  Noise filtering · CPC title

• G10K2210/3056

  Variable gain · CPC title

• G10K2210/3026

  Feedback · CPC title

• G10K2210/3046

  Multiple acoustic inputs, multiple acoustic outputs · CPC title

• G10K2210/3025

  Determination of spectrum characteristics, e.g. FFT · CPC title