Method and apparatus for reducing noise in voices of mobile terminal

• US 9,294,834 B2
• Filed: 04/30/2013
• Issued: 03/22/2016
• Est. Priority Date: 06/25/2012
• Status: Active Grant

• Current Assignee: Honor Device Company Limited
• Original Assignee: Huawei Device Company Limited (Huawei Investment & Holding Co., Ltd.)
• Inventors: Liu, Hongtao, Zhang, Xiaopeng
• Primary Examiner(s): King, Simon
• Application Number:
  US13/873,715
• Publication Number:
  US 20130343560A1
• Time in Patent Office: 1,057 Days
• Field of Search: 381/74
• US Class Current: 1/1
• CPC Class Codes: G10K 11/178 by electro-acoustically regenerating the original acoustic waves in anti-phase
• CPC Class Codes: G10K 2210/1081 Earphones, e.g. for telephones, ear protectors or headsets
• CPC Class Codes: H04M 1/19 Arrangements of transmitters, receivers, or complete sets to prevent eavesdropping, to attenuate local noise or to prevent undesired transmission; Mouthpieces or receivers specially adapted therefor circuit arrangements for preventing eavesdropping H04M1/68; telephone cabinets E04H1/14
• CPC Class Codes: H04M 1/6058 involving the use of a headset accessory device connected to the portable telephone
• CPC Class Codes: H04R 1/1083 Reduction of ambient noise active noise reduction per se G10K11/175; protective devices for the ear, e.g. providing acoustic protection A61F11/06
• CPC Class Codes: H04R 2201/107 Monophonic and stereophonic headphones with microphone for two-way hands free communication
• CPC Class Codes: H04R 2410/05 Noise reduction with a separate noise microphone
• CPC Class Codes: H04R 3/00 Circuits for transducers , loudspeakers or microphones
• CPC Class Codes: H04R 3/005 for combining the signals of two or more microphones specially adapted for hearing aids H04R25/407

Abstract

The present invention discloses a method and an apparatus for reducing noise in voices of a mobile terminal and relates to the field of communications technologies, which can improve the effect of noise reduction. The method includes: selecting, from a voice headphone and a microphone built in the mobile terminal, a current communicating microphone and a current noise reducing microphone; obtaining an audio signal received by the current communicating microphone and an audio signal received by the current noise reducing microphone; performing noise reduction according to the audio signal received by the current communicating microphone and the audio signal received by the current noise reducing microphone, so as to obtain a noise reduced signal; and performing voice coding according to the noise reduced signal to generate an audio output signal.

Claims

1. A method for reducing noise in voices of a mobile terminal, the method comprising:

selecting, from a voice headphone and a microphone built in the mobile terminal, a current communicating microphone and a current noise reducing microphone according to audio energy levels of audio signals received by the voice headphone and the microphone, wherein each of the audio energy levels is a sum of one-period audio energies of the respective audio signal determined from audio signals sampled in each sampling period of a sampling time window, and wherein the one of the voice headphone and the microphone that receives the audio signal corresponding to the greater audio energy is selected as the current communicating microphone and the one of the voice headphone and the microphone that receives the audio signal corresponding to the smaller audio energy is selected as the current noise reducing microphone;

obtaining an audio signal received by the current communicating microphone and an audio signal received by the current noise reducing microphone;

performing noise reduction according to the audio signal received by the current communicating microphone and the audio signal received by the current noise reducing microphone, so as to obtain a noise reduced signal; and

performing voice coding according to the noise reduced signal to generate an audio output signal.

2. The method according to claim 1, wherein selecting, the current communicating microphone and the current noise reducing microphone further comprises:

obtaining an audio signal received by the voice headphone and an audio signal received by the microphone built in the mobile terminal;

obtaining audio energy corresponding to the audio signal received by the voice headphone and audio energy corresponding to the audio signal received by the microphone built in the mobile terminal;

comparing the audio energy corresponding to the audio signal received by the voice headphone with the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal; and

determining greater audio energy and smaller audio energy in the audio energy corresponding to the audio signal received by the voice headphone and the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal.

3. The method according to claim 2, wherein obtaining the audio energy corresponding to the audio signal received by the voice headphone and the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal comprises:

in each sampling period in the sampling time window, performing analog-to-digital conversion on the audio signal received by the voice headphone, so as to obtain a sample audio signal of the voice headphone corresponding to each period, and performing analog-to-digital conversion on the audio signal received by the microphone built in the mobile terminal, so as to obtain a sample audio signal of the microphone built in the mobile terminal corresponding to each period, wherein the sampling time window comprises at least one sampling period;

calculating, according to the sample audio signal of the voice headphone corresponding to each period, to obtain the one-period audio energy of the voice headphone corresponding to each period;

calculating, according to the sample audio signal of the microphone built in the mobile terminal corresponding to each period, to obtain the one-period audio energy of the microphone built in the mobile terminal corresponding to each period; and

determining the sum of the one-period audio energy of the voice headphone corresponding to all periods as the audio energy corresponding to the audio signal received by the voice headphone and determining the sum of the one-period audio energy of the microphone built in the mobile terminal corresponding to all periods as the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal.

4. The method according to claim 3, after calculating according to the sample audio signal of the voice headphone corresponding to each period to obtain a one-period audio energy of the voice headphone corresponding to each period and calculating according to the sample audio signal of the microphone built in the mobile terminal corresponding to each period to obtain one-period audio energy of the microphone built in the mobile terminal corresponding to each period, further comprising:

comparing the one-period audio energy of the voice headphone with the one-period audio energy of the microphone built in the mobile terminal in the same sampling period;

determining greater one-period audio energy and smaller one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone built in the mobile terminal in the same sampling period; and

performing voice coding according to the sample audio signal corresponding to the greater one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone built in the mobile terminal in the same sampling period, so as to obtain the audio output signal.

5. The method according to claim 2, wherein the obtaining an audio energy corresponding to the audio signal received by the voice headphone and an audio energy corresponding to the audio signal received by the microphone built in the mobile terminal comprises:

in each sampling period in a sampling time window, performing analog-to-digital conversion on the audio signal received by the voice headphone, so as to obtain a sample audio signal of the voice headphone corresponding to each period, and performing analog-to-digital conversion on the audio signal received by the microphone built in the mobile terminal, so as to obtain a sample audio signal of the microphone built in the mobile terminal corresponding to each period, wherein the sampling time window comprises at least one sampling period;

calculating according to the sample audio signal of the voice headphone corresponding to each period to obtain one-period audio energy of the voice headphone corresponding to each period, and calculating according to the sample audio signal of the microphone built in the mobile terminal corresponding to each period to obtain one-period audio energy of the microphone built in the mobile terminal corresponding to each period;

determining a mean value of the one-period audio energy of the voice headphone corresponding to all periods as the audio energy corresponding to the audio signal received by the voice headphone; and

determining a mean value of the one-period audio energy of the microphone built in the mobile terminal corresponding to all periods as the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal.

6. The method according to claim 5, after calculating according to the sample audio signal of the voice headphone corresponding to each period to obtain a one-period audio energy of the voice headphone corresponding to each period and calculating according to the sample audio signal of the microphone built in the mobile terminal corresponding to each period to obtain one-period audio energy of the microphone built in the mobile terminal corresponding to each period, further comprising:

comparing the one-period audio energy of the voice headphone with the one-period audio energy of the microphone built in the mobile terminal in the same sampling period;

determining greater one-period audio energy and smaller one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone built in the mobile terminal in the same sampling period; and

performing voice coding according to the sample audio signal corresponding to the greater one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone built in the mobile terminal in the same sampling period, so as to obtain the audio output signal.

7. The method according to claim 1, wherein selecting the current communicating microphone and a current noise reducing microphone comprises:

determining a current voice communicating microphone and a current noise reducing microphone according to pre-stored microphone configuration information.

8. The method of claim 7, further comprising:

receiving microphone configuration modification information which is used to identify a new current communicating microphone and a new current noise reducing microphone; and

substituting the new current communicating microphone and the new current noise reducing microphone for an old current communicating microphone and an old noise reducing microphone according to the microphone configuration modification information.

9. A mobile terminal, comprising:

a selecting unit, configured to select, from a voice headphone and a microphone built in the mobile terminal, a current communicating microphone and a current noise reducing microphone according to audio energy levels of audio signals received by the voice headphone and the microphone, wherein each of the audio energy levels is a sum of one-period audio energies of the respective audio signal determined from audio signals sampled in each sampling period of a sampling time window, and wherein the one of the voice headphone and the microphone that receives the audio signal corresponding to the greater audio energy is selected as the current communicating microphone and the one of the voice headphone and the microphone that receives the audio signal corresponding to the smaller audio energy is selected as the current noise reducing microphone;

an obtaining unit, configured to obtain an audio signal received by the current communicating microphone selected by the selecting unit and an audio signal received by the current noise reducing microphone selected by the selecting unit;

a noise reducing unit, configured to perform noise reduction according to the audio signal received by the current communicating microphone and the audio signal received by the current noise reducing microphone that are obtained by the obtaining unit, so as to obtain a noise reduced signal; and

a voice coding processing unit, configured to perform voice coding according to the noise reduced signal generated by the noise reducing unit, so as to generate an audio output signal.

10. The mobile terminal according to claim 9, wherein the selecting unit comprises:

a first obtaining module, configured to obtain the audio signal received by the voice headphone and the audio signal received by the microphone built in the mobile terminal;

a second obtaining module, configured to obtain audio energy corresponding to the audio signal that is received by the voice headphone and obtained by the first obtaining module, and audio energy corresponding to the audio signal that is received by the microphone built in the mobile terminal and obtained by the first obtaining module; and

a comparing module, configured to compare the audio energy corresponding to the audio signal received by the voice headphone with the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal, wherein the two types of audio energy are obtained by the second obtaining module, and to determine greater audio energy and smaller audio energy in the audio energy corresponding to the audio signal received by the voice headphone and the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal.

11. The mobile terminal according to claim 10, wherein the second obtaining module comprises:

an analog-to-digital converting submodule, configured to, in each sampling period in the sampling time window, perform analog-to-digital conversion on the audio signal received by the voice headphone, so as to obtain a sample audio signal of the voice headphone corresponding to each period, and perform analog-to-digital conversion on the audio signal received by the microphone built in the mobile terminal, so as to obtain a sample audio signal of the microphone built in the mobile terminal corresponding to each period, wherein the sampling time window comprises at least one sampling period;

a calculating submodule, configured to calculate according to the sample audio signal of the voice headphone corresponding to each period generated by the analog-to-digital converting submodule, so as to obtain the one-period audio energy of the voice headphone corresponding to each period, and calculate according to the sample audio signal of the microphone built in the mobile terminal corresponding to each period generated by the analog-to-digital converting submodule, so as to obtain the one-period audio energy of the microphone built in the mobile terminal corresponding to each period; and

a determining submodule, configured to determine the sum of the one-period audio energy of the voice headphone corresponding to all periods obtained by the calculating submodule as the audio energy corresponding to the audio signal received by the voice headphone, and determine the sum of the one-period audio energy of the microphone built in the mobile terminal corresponding to all periods obtained by the calculating submodule as the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal.

12. The mobile terminal according to claim 11, wherein the determining submodule is further configured to determine a mean value of the one-period audio energy of the voice headphone corresponding to all periods obtained by the calculating submodule as the audio energy corresponding to the audio signal received by the voice headphone, and determine a mean value of the one-period audio energy of the microphone built in the mobile terminal corresponding to all periods obtained by the calculating submodule as the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal.

13. The mobile terminal according to claim 11, wherein the comparing module is further configured to compare one-period audio energy of the voice headphone with one-period audio energy of the microphone built in the mobile terminal in the same sampling period, and to determine greater one-period audio energy and smaller one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone built in the mobile terminal in the same sampling period;

and

the voice coding processing unit is further configured to perform voice coding according to the sample audio signal corresponding to the greater one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone built in the mobile terminal in the same sampling period that are obtained by the comparing module, so as to obtain the audio output signal.

14. The mobile terminal according to claim 9, wherein the selecting unit further comprises:

a determining module, configured to determine the current communicating microphone and the current noise reducing microphone according to pre-stored microphone configuration information, wherein the pre-stored microphone configuration information is used to identify the current communicating microphone and the current noise reducing microphone.

15. The mobile terminal according to claim 14, further comprising:

a receiving unit, configured to receive microphone configuration modification information, wherein the microphone configuration modification information is used to identify a new current communicating microphone and a new current noise reducing microphone; and

a modifying unit, configured to substitute the new current communicating microphone and the new current noise reducing microphone for an old current communicating microphone and an old noise reducing microphone according to the microphone configuration modification information received by the receiving unit.

16. A mobile terminal, comprising:

a microphone;

a processor connected to the microphone;

a non-transitory computer readable medium connected to the processor and having stored thereon instructions that, when executed, cause the processor to;

select, from a voice headphone and the microphone, a current communicating microphone and a current noise reducing microphone according to audio energy levels of first audio signals received by the voice headphone and the microphone, wherein each of the audio energy levels is a sum of one-period audio energies of the respective first audio signal determined from sample audio signals sampled in each sampling period of a sampling time window, and wherein the one of the voice headphone and the microphone that receives the one of the first audio signals corresponding to the greater audio energy is selected as the current communicating microphone and the one of the voice headphone and the microphone that receives the one of the first audio signals corresponding to the smaller audio energy is selected as the current noise reducing microphone;

obtain a second audio signal received by the current communicating microphone and a third audio signal received by the current noise reducing microphone;

perform noise reduction according to second the audio signal and the third audio signal, so as to obtain a noise reduced signal; and

perform voice coding according to the noise reduced signal, so as to generate an audio output signal.

17. The mobile terminal according to claim 16, wherein the instructions causing the processor to select a current communicating microphone and a current noise reducing microphone further comprise instructions that, when executed, cause the processor to:

obtain an audio signal received by the voice headphone and an audio signal received by the microphone;

obtain a first audio energy corresponding to the audio signal that is received by the voice headphone and obtain a second audio energy corresponding to the audio signal that is received by the microphone;

compare the first audio energy with the second audio energy; and

determine a greater audio energy and a smaller audio energy of the first audio energy and the second audio energy.

18. The mobile terminal according to claim 17, wherein the instructions causing the processor to obtain the first audio energy the second audio energy further comprise instructions that, when executed, cause the processor to:

perform analog-to-digital conversion on the audio signal received by the voice headphone in each sampling period in a sampling time window, so as to obtain a first sample audio signal of the voice headphone corresponding to each period;

perform analog-to-digital conversion on the audio signal received by the microphone by in each sampling period in the sampling time window, so as to obtain a second sample audio signal of the microphone corresponding to each period;

calculate, according to the first sample audio signal, the one-period audio energy of the voice headphone corresponding to each period;

calculate according to the second sample audio signal, the one-period audio energy of the microphone corresponding to each period;

determine the sum of the one-period audio energy of the voice headphone corresponding to all periods as the audio energy corresponding to the audio signal received by the voice headphone; and

determine the sum of the one-period audio energy of the microphone corresponding to all periods as the audio energy corresponding to the audio signal received by the microphone built in the mobile terminal;

wherein the sampling time window comprises at least one sampling period.

19. The mobile terminal according to claim 18, wherein the instructions causing the processor to compare the first audio energy with the second audio energy further comprise instructions that, when executed, cause the processor to compare a one-period audio energy of the voice headphone with a one-period audio energy of the microphone in the same sampling period;

wherein the instructions causing the processor to determine a greater audio energy and a smaller audio energy of the first audio energy and the second audio energy further comprise instructions that, when executed, cause the processor to determine a greater one-period audio energy and a smaller one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone in the same sampling period; and

wherein the instructions causing the processor to perform voice coding according to the noise reduced signal further comprise instructions that, when executed, cause the processor to perform voice coding according to sample audio signal corresponding to the greater one-period audio energy in the one-period audio energy of the voice headphone and the one-period audio energy of the microphone in the same sampling period, so as to obtain the audio output signal.

20. The mobile terminal according to claim 18, wherein the instructions causing the processor to determine the sum of the one-period audio energy of the voice headphone and of the microphone further comprise instructions that, when executed, cause the processor to:

determine a mean value of the one-period audio energy of the voice headphone corresponding to all periods as the audio energy corresponding to the audio signal received by the voice headphone; and

determine a mean value of the one-period audio energy of the microphone corresponding to all periods as the audio energy corresponding to the audio signal received by the microphone.