WO2013107307A1

WO2013107307A1 - Noise reduction method and device

Info

Publication number: WO2013107307A1
Application number: PCT/CN2013/070096
Authority: WO
Inventors: 魏孔刚; 谢葱茏; 钟光华
Original assignee: 华为终端有限公司
Priority date: 2012-01-16
Filing date: 2013-01-06
Publication date: 2013-07-25
Also published as: CN102543097A

Abstract

The present invention provides a noise reduction method and device. In the present invention, a first sound pressure of audio data received by a first audio input device and a second sound pressure of the audio data received by a second audio input device are obtained, so that noise reduction processing can be performed on the audio data according to a difference value between the first sound pressure and the second sound pressure and a preset sound pressure threshold value, and therefore the problem in the prior art of inhibiting speech signals at the same level as noise signals because the distances between a signal source corresponding to a sound signal and two microphones change, thereby enhancing the sound quality after noise reduction and the reliability of noise reduction.

Description

TECHNICAL FIELD The present invention relates to noise processing technologies, and in particular, to a noise reduction method and apparatus.

BACKGROUND OF THE INVENTION As sound processing technology develops faster and faster, terminal equipment demands higher and higher sound quality that needs to be processed, and noise reduction technology emerges as the times require. The current noise reduction technology mainly uses two microphones to actively reduce noise. Through a certain algorithm, the audio data (ie, voice signal and noise) received by two microphones are calculated to determine which are voice signals and which are noises, and then The speech signal is separated from the noise, ie the noise is suppressed.

However, if the distance between the signal source corresponding to the sound signal (for example, the human mouth) and the two microphones changes, the speech signal may be determined to be noise, so that the speech signal is also suppressed to the same degree as the noise signal. , seriously affecting the sound quality after noise reduction, resulting in a reduction in the reliability of noise reduction.

SUMMARY OF THE INVENTION The present invention provides a noise reduction method and apparatus for improving sound quality and noise reduction reliability after noise reduction.

One aspect provides a method of noise reduction, including:

Obtaining a first sound pressure of the audio data received by the first audio input device and a second sound pressure of the audio data received by the second audio input device;

And denoising the audio data according to a difference between the first sound pressure and the second sound pressure and a preset sound pressure threshold.

Another aspect provides a noise reduction device, including:

And an obtaining unit, configured to obtain a first sound pressure of the audio data received by the first audio input device and a second sound pressure of the audio data received by the second audio input device;

And a processing unit, configured to perform noise reduction processing on the audio data according to a difference between the first sound pressure and the second sound pressure and a preset sound pressure threshold.

According to the foregoing technical solution, the first sound pressure of the audio data received by the first audio input device and the second sound pressure of the audio data received by the second audio input device are obtained by the embodiment of the present invention. The noise data can be denoised according to the difference between the first sound pressure and the second sound pressure and the preset sound pressure threshold, so that the signal source corresponding to the sound signal and the two in the prior art can be avoided. The problem that the speech signal is suppressed to the same degree as the noise signal caused by the change of the distance between the microphones improves the sound quality and the reliability of noise reduction after noise reduction.

BRIEF DESCRIPTION OF THE DRAWINGS In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description of the drawings used in the embodiments or the prior art description will be briefly described below. The drawings are some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive labor.

1 is a schematic flowchart of a noise reduction method according to an embodiment of the present invention;

2 is a schematic diagram showing the setting of a double microphone on a terminal device for collecting sound signals by two microphones in the embodiment corresponding to FIG. 1;

FIG. 3 is a schematic structural diagram of a noise reduction device according to another embodiment of the present invention.

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. The embodiments are a part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

FIG. 1 is a schematic flowchart of a noise reduction method according to an embodiment of the present invention. As shown in FIG. 1 , the noise reduction method of this embodiment may include:

101. Obtain a first sound pressure of the audio data received by the first audio input device and a second sound pressure of the audio data received by the second audio input device.

Optionally, since the frequency response range of the audio input device is wide, in order to avoid interference with the algorithm generated by the non-speech data, the audio data may be audio data in a preset frequency range, thereby further improving the reliability of the noise reduction. For example: The preset frequency range can be set to the human voice range, 300 Hz -3400 Hz, which can be achieved by a bandpass filter.

102. Perform noise reduction processing on the audio data according to a difference between the first sound pressure and the second sound pressure and a preset sound pressure threshold.

For example: if the difference between the first sound pressure and the second sound pressure is greater than or equal to the preset sound pressure threshold, Using the first noise reduction parameter, performing noise reduction processing on the audio data; if the difference between the first sound pressure and the second sound pressure is less than a preset sound pressure threshold, using the second noise reduction parameter, the audio data is used And performing noise reduction processing; wherein, the noise reduction amount corresponding to the first noise reduction parameter is greater than the noise reduction amount corresponding to the second noise reduction parameter.

Further, in this embodiment, if the difference between the first sound pressure and the second sound pressure is less than the preset sound pressure threshold, the prompt may further be prompted to adjust the signal corresponding to the signal in the audio data. The distance between the source and the first audio input device or the second audio input device described above. If the adjustment is not performed within a predetermined time, the difference between the first sound pressure and the second sound pressure is still less than the preset sound pressure threshold. At this time, the prompt is not performed, and the second noise reduction parameter is directly used. The above audio data is subjected to noise reduction processing.

It should be noted that, in this embodiment, according to the distance between the signal source corresponding to the sound signal and the two microphones, which of the two audio input devices of the first audio input device and the second audio input device is used as the main Audio input device, which is used as an auxiliary audio input device. In normal use, the signal source corresponding to the sound signal should be close to the main audio input device.

In this embodiment, by obtaining the first sound pressure of the audio data received by the first audio input device and the second sound pressure of the audio data received by the second audio input device, enabling the first sound pressure according to the above The difference between the second sound pressure and the preset sound pressure threshold, and the noise reduction processing on the audio data can avoid the pair of voices caused by the change of the distance between the signal source corresponding to the sound signal and the two microphones in the prior art. The signal performs the same degree of suppression as the noise signal, thereby improving the sound quality and noise reduction reliability after noise reduction.

The technical solution provided by the embodiment of the present invention can be applied to noise reduction of a mobile phone that collects sound signals through two or more microphones. In order to make the method provided by the embodiment of the present invention more clear, the following is an example of performing noise reduction on a terminal device that performs sound signal collection through a dual microphone. As shown in Fig. 2, S1 is the distance from the mouth to the auxiliary microphone, and S2 is the distance from the mouth to the main microphone. In general, S1 is several times larger than S2. For sound signals (sound waves), the sound signal will have a certain attenuation in the air (especially when the auxiliary microphone is on the back of the phone, the sound signal needs to bypass the phone), so the sound pressure of the sound signals received by the two microphones The sizes are not equal, usually the main microphone is much larger than the auxiliary microphone. For ambient noise, the noise source corresponding to the noise is far from the two microphones. Therefore, the distance from the noise source to the main microphone is approximately equal to the distance from the noise source to the auxiliary microphone, that is, the noise received by the two microphones. The sound pressure levels are essentially equal.

When the mouth is very close to the main microphone, the normal noise reduction method in the prior art can be utilized (ie Standard noise reduction parameters), noise reduction processing of audio data.

When the mouth is getting farther and farther away from the main microphone, the difference between the sound pressure of the sound signal received by the main microphone and the sound pressure of the sound signal received by the auxiliary microphone becomes smaller and smaller, and the phase is getting closer and closer. When the difference is less than a certain value (for example, 10 decibels), you can make a prompt. For example: When the prompt is played through the handset, the user is prompted to speak the mouth close to the main microphone. If the user does not make adjustments, the next time if the difference between the sound signal received by the primary microphone and the sound signal received by the auxiliary microphone continues to be less than a certain value (for example, 10 dB), then it can be utilized with the normal in the prior art. Noise reduction method (ie standard noise reduction parameter) Different noise reduction methods, the noise reduction processing of the audio data, the noise reduction amount of the noise reduction parameter used by the noise reduction method is smaller than the noise reduction amount of the standard noise reduction parameter, so that timely The speech signal is determined to be noise, but the amount of noise reduction is automatically reduced to ensure the quality of the call, thereby improving the reliability of the noise reduction.

It should be noted that, for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should understand that the present invention is not limited by the described action sequence. Because in accordance with the present invention, certain steps may be performed in other sequences or concurrently. In addition, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present invention.

In the above embodiments, the descriptions of the various embodiments are different, and the details are not described in the specific embodiments. For details, refer to related descriptions of other embodiments.

FIG. 3 is a schematic structural diagram of a noise reduction device according to another embodiment of the present invention. As shown in FIG. 3, the noise reduction device of this embodiment may include an obtaining unit 31 and a processing unit 32. The obtaining unit 31 is configured to obtain a first sound pressure of the audio data received by the first audio input device and a second sound pressure of the audio data received by the second audio input device; and the processing unit 32 is configured to obtain, according to the obtaining unit 31, And obtaining the difference between the first sound pressure and the second sound pressure and the preset sound pressure threshold, and performing noise reduction processing on the audio data. Optionally, since the frequency response range of the audio input device is wide, in order to avoid interference with the algorithm generated by the non-speech data, the audio data may be audio data in a preset frequency range, thereby further improving the reliability of the noise reduction. For example: The preset frequency range can be set to the human voice range, 300 Hz -3400 Hz, which can be achieved by a bandpass filter.

For example, the processing unit 32 in this embodiment may be specifically configured to: when the difference between the first sound pressure and the second sound pressure is greater than or equal to a preset sound pressure threshold, using the first noise reduction parameter, the audio Data Performing noise reduction processing; or may be further configured to perform noise reduction processing on the audio data by using a second noise reduction parameter when a difference between the first sound pressure and the second sound pressure is less than a preset sound pressure threshold; The noise reduction amount corresponding to the first noise reduction parameter is greater than the noise reduction amount corresponding to the second noise reduction parameter.

Further, the processing unit 32 in this embodiment may be further configured to: when the difference between the first sound pressure and the second sound pressure is less than a preset sound pressure threshold, prompting to adjust the audio data The distance between the signal source corresponding to the signal and the first audio input device or the second audio input device.

In this embodiment, the first sound pressure of the audio data received by the first audio input device and the second sound pressure of the audio data received by the second audio input device are obtained by the obtaining unit, so that the processing unit can be obtained according to the obtaining unit. The difference between the first sound pressure and the second sound pressure and the preset sound pressure threshold are used to perform noise reduction processing on the audio data, thereby avoiding the signal source corresponding to the sound signal and the two microphones in the prior art. The problem of the speech signal being suppressed to the same degree as the noise signal caused by the change of the distance between the two, thereby improving the sound quality and the reliability of noise reduction after noise reduction.

A person skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system, the device and the unit described above may refer to the corresponding processes in the foregoing method embodiments, and details are not described herein again.

In the several embodiments provided herein, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be electrical, mechanical or otherwise. The components displayed by the unit may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of hardware plus software functional units. The above-described integrated unit implemented in the form of a software functional unit can be stored in a computer readable storage medium. The software functional unit described above is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, server, or network device, etc.) to perform portions of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: a U disk, a mobile hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a disk or an optical disk, and the like, and the program code can be stored. Medium.

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced. The modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request

A noise reduction method, comprising:

2. The method according to claim 1, wherein the audio data is audio data within a preset frequency range.

The method according to claim 1 or 2, wherein the audio data is performed according to a difference between the first sound pressure and the second sound pressure and a preset sound pressure threshold The noise reduction process includes: if the difference between the first sound pressure and the second sound pressure is greater than or equal to a preset sound pressure threshold, using the first noise reduction parameter to perform noise reduction processing on the audio data;

If the difference between the first sound pressure and the second sound pressure is less than a preset sound pressure threshold, the audio data is subjected to noise reduction processing by using a second noise reduction parameter;

The noise reduction amount corresponding to the first noise reduction parameter is greater than the noise reduction amount corresponding to the second noise reduction parameter.

The method according to claim 3, wherein the noise reduction is performed on the audio data according to a difference between the first sound pressure and the second sound pressure and a preset sound pressure threshold The processing further includes: if the difference between the first sound pressure and the second sound pressure is less than a preset sound pressure threshold, prompting to prompt to adjust a signal source and a signal corresponding to the signal in the audio data The distance between the first audio input device or the second audio input device.

5. A noise reduction device, comprising:

6. The device according to claim 5, wherein the audio data is audio data within a preset frequency range.

The device according to claim 5 or 6, wherein the processing unit is specifically configured to: when a difference between the first sound pressure and the second sound pressure is greater than or equal to a preset sound pressure threshold Use a first noise reduction parameter, performing noise reduction processing on the audio data;

When the difference between the first sound pressure and the second sound pressure is less than the preset sound pressure threshold, the audio data is subjected to noise reduction processing by using the second noise reduction parameter;

The device according to claim 7, wherein the processing unit is further configured to: when the difference between the first sound pressure and the second sound pressure is less than a preset sound pressure threshold And prompting to adjust a distance between a signal source corresponding to the signal in the audio data and the first audio input device or the second audio input device.