CN116887126A

CN116887126A - Noise cancellation method, device, equipment and computer readable storage medium

Info

Publication number: CN116887126A
Application number: CN202310854190.2A
Authority: CN
Inventors: 赵玉萍; 刘广升; 吴劼; 安康; 黄若舟; 朱宗霞; 尹建朋; 谢荣良; 周宇
Original assignee: Goertek Techology Co Ltd
Current assignee: Goertek Techology Co Ltd
Priority date: 2023-07-12
Filing date: 2023-07-12
Publication date: 2023-10-13

Abstract

The present invention relates to the field of signal processing technologies, and in particular, to a method, an apparatus, a device, and a computer readable storage medium for noise cancellation, where the method includes: acquiring an environmental sound signal of an external environment where the audio equipment is located, and determining an environmental noise level of the environmental sound signal; acquiring an input audio signal of an audio device, and determining a base gain of a noise cancellation filter of the audio device based on the input audio signal; adjusting the basic gain based on the environmental noise level to obtain a filter gain, wherein the filter gain and the environmental noise level form a negative correlation; the input audio signal of the audio device is processed by the filter gain to eliminate noise when the input audio signal is played. The invention realizes that the noise elimination method is suitable for different environmental noises, and the noise elimination method can meet the requirements of different environmental noises, thereby improving the practicability of the noise elimination method.

Description

Noise cancellation method, device, equipment and computer readable storage medium

Technical Field

The present invention relates to the field of signal processing technologies, and in particular, to a method, an apparatus, a device, and a computer readable storage medium for noise cancellation.

Background

In recent years, audio devices have become an integral part of people's lives. However, due to the audio signal and the structure of the speaker itself of the audio device, noise may occur in the speaker when playing the audio signal, for example, when the amplitude of the audio signal is too large, the speed or vibration amount of the diaphragm in the small speaker is relatively large, and even if the amplitude of the diaphragm does not exceed the maximum design amplitude at this time, noise occurs in the audio signal played by the small speaker; for example, when the cavity of the speaker is small, the speaker is easily distorted by the impact of the audio signal with low frequency or large amplitude, and the played audio signal is noisy; airflow noise may also occur, for example, when the airflow rubs against the sound outlet of the speaker.

At present, noise elimination of an audio signal mainly adopts a feedforward processing method, and the method determines a filter gain based on parameters such as a force coefficient of a loudspeaker and rigidity of a loudspeaker diaphragm and performs feedforward processing on the audio signal through the filter gain so as to eliminate noise of the audio signal during playing. However, the requirements for eliminating the noise in different use scenes are different, and the above noise eliminating method cannot meet the requirements for eliminating the noise in different scenes in actual use, which affects the practicability of the noise eliminating method.

Disclosure of Invention

The main object of the present invention is to provide a noise cancellation method, apparatus, device and computer readable storage medium, which can meet the requirements of different environmental noise, thereby improving the practicability of the noise cancellation method.

In order to achieve the above object, the present invention provides a noise cancellation method including the steps of:

acquiring an environmental sound signal of an external environment where audio equipment is located, and determining an environmental noise level of the environmental sound signal;

acquiring an input audio signal of the audio device and determining a base gain of a noise cancellation filter of the audio device based on the input audio signal;

adjusting the basic gain based on the environmental noise level to obtain a filter gain, wherein the filter gain and the environmental noise level form a negative correlation;

and processing the input audio signal through the filter gain so as to eliminate noise when the input audio signal is played.

Optionally, the step of adjusting the base gain based on the environmental noise level to obtain a filter gain includes:

Determining a target noise cancellation coefficient based on the environmental noise level and a preset mapping relation, wherein the preset mapping relation comprises corresponding relations between different signal noise levels and the target noise cancellation coefficient;

and processing the basic gain through the target noise elimination coefficient to obtain a filter gain.

Optionally, the preset mapping relation includes a first calculation formula and a second calculation formula, and the step of determining the noise cancellation coefficient based on the environmental noise level and the preset mapping relation includes:

if the environmental noise level is greater than or equal to a first preset level, calculating to obtain a target noise elimination coefficient based on the environmental noise level and the first calculation formula, wherein the target noise elimination coefficient calculated based on the first calculation formula is less than or equal to 1;

and if the environmental noise level is smaller than the first preset level, calculating to obtain the target noise elimination coefficient based on the environmental noise level and the second calculation formula, wherein the target noise elimination coefficient calculated based on the second calculation formula is larger than 1.

Optionally, the preset mapping relationship includes preset noise cancellation coefficients corresponding to a plurality of signal noise levels, and the step of determining the target noise cancellation coefficient based on the environmental noise level and the preset mapping relationship includes:

And determining a target noise cancellation coefficient corresponding to the environment noise level from preset noise cancellation coefficients corresponding to each of a plurality of signal noise levels.

Optionally, before the step of determining the target noise cancellation coefficient corresponding to the environmental noise level from the preset noise cancellation coefficients corresponding to each of the plurality of signal noise levels, the method further includes:

acquiring acoustic parameters of the audio equipment, wherein the acoustic parameters comprise structural parameters of the audio equipment and/or signal processing parameters of the audio equipment;

and determining the preset noise elimination coefficient corresponding to each of the plurality of signal noise levels based on the acoustic parameters.

Optionally, the step of determining the base gain of the noise cancellation filter of the audio device based on the input audio signal comprises:

extracting distortion characteristics of the input audio signal, and carrying out noise recognition on the input audio signal based on the distortion characteristics to obtain a noise recognition result, wherein the noise recognition result is used for representing signal characteristics of noise when the input audio signal is played;

and determining a basic gain of a noise cancellation filter of the audio device based on the noise identification result.

Optionally, after the step of determining the ambient noise level of the ambient sound signal, the method further comprises:

detecting whether the environmental noise level is smaller than or equal to a second preset level;

and if the environmental noise level is smaller than the second preset level, executing the steps of acquiring the input audio signal of the audio device and determining the basic gain of the noise elimination filter of the audio device based on the input audio signal.

In order to achieve the above object, the present invention also provides a noise cancellation device including:

the acquisition module is used for acquiring an environmental sound signal of an external environment where the audio equipment is located and determining the environmental noise level of the environmental sound signal;

a determining module, configured to obtain an input audio signal of the audio device, and determine a base gain of a noise cancellation filter of the audio device based on the input audio signal;

the adjusting module is used for adjusting the basic gain based on the environmental noise level to obtain a filter gain, wherein the filter gain and the environmental noise level form a negative correlation;

and the noise elimination module is used for processing the input audio signal through the filter gain so as to eliminate noise when the input audio signal is played.

To achieve the above object, the present invention also provides a noise canceling apparatus comprising: a memory, a processor, and a noise cancellation program stored on the memory and executable on the processor, which when executed by the processor, implements the steps of the noise cancellation method as described above.

In addition, in order to achieve the above object, the present invention also proposes a computer-readable storage medium having stored thereon a noise cancellation program which, when executed by a processor, implements the steps of the noise cancellation method as described above.

According to the invention, the environment sound signal of the external environment where the audio equipment is located is obtained, and the environment noise level of the environment sound signal is determined; acquiring an input audio signal of an audio device, and determining a base gain of a noise cancellation filter of the audio device based on the input audio signal; adjusting the basic gain based on the environmental noise level to obtain a filter gain, wherein the filter gain and the environmental noise level form a negative correlation; the input audio signal of the audio device is processed by the filter gain to eliminate noise when the input audio signal is played.

The invention determines a filter gain for noise cancellation of an input audio signal based on an ambient noise level, wherein the filter gain is inversely related to the ambient noise level. That is, the greater the noise level, the smaller the filter gain, the smaller the degree of noise cancellation performed on the input audio signal, and since the greater the noise level, the greater the external environmental noise, the noise generated when the audio device plays the input audio signal is masked by the external noise, and the user can hardly hear the noise when the input audio signal is played, the invention can ensure the noise cancellation effect while reducing the calculation amount and the power consumption of the signal processing system; the noise level is smaller, noise generated when the audio equipment plays the input audio signal is clear and audible, at the moment, the gain of the filter is larger, so that the noise elimination degree of the input audio signal is larger, the hearing of a user is improved, in sum, the noise elimination method is adapted to different environmental noises, the noise elimination method can meet the requirements of different environmental noises, and the practicability of the noise elimination method is improved.

Drawings

FIG. 1 is a schematic diagram of a hardware operating environment according to an embodiment of the present invention;

FIG. 2 is a flowchart of a noise cancellation method according to a first embodiment of the present invention;

FIG. 3 is a flow chart of a noise cancellation method according to an embodiment of the present invention;

fig. 4 is a functional block diagram of a noise cancellation device according to a preferred embodiment of the present invention.

The achievement of the objects, functional features and advantages of the present invention will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

Referring to fig. 1, fig. 1 is a schematic device structure of a hardware running environment according to an embodiment of the present invention.

It should be noted that, in the embodiment of the present invention, the noise cancellation device may be an audio device with an audio playing function, for example, a device such as an earphone or a smart phone, or may be an intelligent device that establishes a communication connection with the audio device, for example, a device such as a personal computer or a server, which is not limited herein.

As shown in fig. 1, the noise canceling device may include: a processor 1001, such as a CPU, a network interface 1004, a user interface 1003, a memory 1005, a communication bus 1002. Wherein the communication bus 1002 is used to enable connected communication between these components. The user interface 1003 may include a Display, an input unit such as a Keyboard (Keyboard), and the optional user interface 1003 may further include a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface). The memory 1005 may be a high-speed RAM memory or a stable memory (non-volatile memory), such as a disk memory. The memory 1005 may also optionally be a storage device separate from the processor 1001 described above.

It will be appreciated by those skilled in the art that the device structure shown in fig. 1 does not constitute a limitation of the noise cancellation device, and may include more or fewer components than shown, or may combine certain components, or a different arrangement of components.

As shown in fig. 1, an operating system, a network communication module, a user interface module, and a noise cancellation program may be included in the memory 1005, which is a type of computer storage medium. The operating system is a program that manages and controls the hardware and software resources of the device, supporting the execution of noise cancellation programs and other software or programs. In the device shown in fig. 1, the user interface 1003 is mainly used for data communication with the client; the network interface 1004 is mainly used for establishing communication connection with a server; and the processor 1001 may be configured to call a noise canceling program stored in the memory 1005 and perform the following operations:

Further, the step of adjusting the base gain based on the ambient noise level to obtain a filter gain includes:

Further, the predetermined mapping relation includes a first calculation formula and a second calculation formula, and the step of determining the noise cancellation coefficient based on the environmental noise level and the predetermined mapping relation includes:

Further, the preset mapping relationship includes preset noise cancellation coefficients corresponding to the plurality of signal noise levels, and the step of determining the target noise cancellation coefficient based on the environmental noise level and the preset mapping relationship includes:

Further, before the step of determining the target noise cancellation coefficient corresponding to the environmental noise level from the preset noise cancellation coefficients corresponding to the signal noise levels, the method further includes:

Further, the step of determining a base gain of a noise cancellation filter of the audio device based on the input audio signal comprises:

Further, after the step of determining the ambient noise level of the ambient sound signal, the processor 1001 may be further configured to invoke a noise cancellation program stored in the memory 1005 to perform the following operations:

Based on the above-described structure, various embodiments of the noise cancellation method are proposed.

Referring to fig. 2, fig. 2 is a flowchart illustrating a noise cancellation method according to a first embodiment of the present invention.

Embodiments of the present invention provide embodiments of methods of noise cancellation, it being noted that although a logic sequence is shown in the flow diagrams, in some cases the steps shown or described may be performed in a different order than that shown or described herein. In this embodiment, the execution body of the noise cancellation method may be an audio device having an audio playing function, such as an earphone, a smart phone, or an intelligent device that establishes a communication connection with the audio device, such as a personal computer, a server, etc., which is not limited in this embodiment, and the explanation of each embodiment by the execution body is omitted for convenience of description. In this embodiment, the noise cancellation method includes:

step S10, acquiring an environmental sound signal of an external environment where the audio equipment is located, and determining an environmental noise level of the environmental sound signal;

in recent years, audio devices have become an integral part of people's lives. However, due to the audio signal and the structure of the speaker of the audio device, noise may occur when the speaker plays the audio signal, for example, when the amplitude of the audio signal is too large, the speed or vibration amount of the diaphragm in the speaker is relatively large, even if the amplitude of the diaphragm does not exceed the maximum design amplitude at this time, the noise occurs in the audio signal played by the speaker; for example, when the cavity of the speaker is small, the speaker is easily distorted by the impact of the audio signal with low frequency or large amplitude, and the played audio signal is noisy; airflow noise may also occur, for example, when the airflow rubs against the sound outlet of the speaker.

In particular, for small portable audio devices mentioned in audio devices, for example, AR (Augmented Reality ) devices, VR (Virtual Reality) devices, smart audio glasses, neck speakers, open headphones, mobile phones, and tablet devices, small speakers are usually disposed on such portable audio devices, and the small speakers are smaller in diaphragm and cavity, so that they are more prone to generate a large amount of distortion under the impact of low-frequency and large-amplitude sound sources, resulting in noise.

In general, the noise phenomenon in the audio signal is related to the noise signal in the external environment, and the larger the noise level is, the larger the noise in the external environment is, so that the noise can be covered to a certain extent; the smaller the noise level, the less noise in the external environment and the more pronounced the noise. Therefore, in this embodiment, by combining the environmental noise levels, the degree of noise cancellation on the input audio signal is determined according to different environmental noise levels, so that the smaller the environmental noise level is, the larger the filter gain is, and the greater the degree of noise cancellation on the input audio signal is, thereby improving the effect of noise cancellation.

Specifically, in this embodiment, an ambient sound signal of an external environment in which the audio device is located is obtained, and an ambient noise level of the ambient sound signal is determined. In a possible implementation, the decibel value of the ambient sound signal may be taken as the ambient noise level; in another possible implementation manner, a plurality of signal noise levels may be preset, each signal noise level corresponds to a different decibel value range, and the decibel value range corresponding to the decibel value of the environmental sound signal is determined, so that the environmental noise level of the environmental sound signal is determined.

Step S20, obtaining an input audio signal of the audio equipment, and determining a basic gain of a noise elimination filter of the audio equipment based on the input audio signal;

in this embodiment, an input audio signal of an audio device is acquired, and the gain of a noise cancellation filter of the audio device is determined based on the input audio signal, which is hereinafter referred to as a base gain to show distinction, and in this embodiment, the base gain refers to a gain that has not been processed based on the environmental noise level. In a specific embodiment, the base gain may be determined according to a conventional noise cancellation method, for example, in a possible embodiment, when noise cancellation is performed by adopting a feedforward filtering manner, the gain determined based on parameters such as a force coefficient of a speaker and rigidity of a speaker diaphragm may be used as the base gain, which is not described herein.

Step S30, adjusting the basic gain based on the environmental noise level to obtain a filter gain, wherein the filter gain and the environmental noise level form a negative correlation;

in this embodiment, after determining the environmental noise level and the base gain, the base gain is adjusted based on the environmental noise level to obtain a filter gain that is finally used for noise cancellation, where the filter gain and the environmental noise level are in a negative correlation.

In a possible implementation, the coefficient for adjusting the base gain (hereinafter referred to as a target noise cancellation coefficient for distinguishing) may be determined based on the environmental noise level, and the filter gain is obtained by processing the base gain through the noise cancellation coefficient, where the specific processing procedure is not limited, and the filter gain obtained by processing satisfies: the filter gain and the ambient noise level are inversely related.

And step S40, processing the input audio signal through the filter gain to eliminate noise when the input audio signal is played.

After the filter gain is determined, the input audio signal is processed through the filter gain to obtain a noise elimination signal with the same amplitude and opposite phase to the noise when the input audio signal is played, and the noise elimination signal and the input audio signal are played together through a loudspeaker so as to eliminate noise generated when the input audio signal is played through the noise elimination signal.

Further, in a possible embodiment, step S20 includes:

step S201, extracting distortion characteristics of the input audio signal, and carrying out noise recognition on the input audio signal based on the distortion characteristics to obtain a noise recognition result, wherein the noise recognition result is used for representing signal characteristics of noise when the input audio signal is played;

in this embodiment, distortion characteristics of an input audio signal are extracted, and noise recognition is performed on the input audio signal based on the distortion characteristics to obtain a noise recognition result. The distortion characteristics are distortion unique characteristics of the input audio signal, which are different from the undistorted sound signal, and include but are not limited to short-time energy, mel-frequency cepstrum coefficient and the like. The noise recognition result is used for representing signal characteristics of noise when the input audio signal is played, and specifically may include a frequency band and a noise peak value for generating the noise.

In this embodiment, the noise recognition method is not limited, and may include, but not limited to, a threshold method, a deep learning method, a decision tree method, and the like, which are not described herein.

Step S202, determining a basic gain of a noise cancellation filter of the audio device based on the noise identification result.

In this embodiment, the base gain of the noise cancellation filter of the audio device is determined based on the noise recognition result. The specific manner of determining the base gain may refer to steps S10 to S40, and will not be described herein.

Further, in a possible embodiment, after the step S10, the method further includes:

step S50, detecting whether the environmental noise level is smaller than a second preset level;

since in general, the noise phenomenon of an input audio signal is related to the level of ambient noise, the greater the level of ambient noise, the less noticeable the noise; the smaller the ambient noise level, the more pronounced the noise. Therefore, in this embodiment, before the noise cancellation is performed, it is determined whether the environmental noise level of the input audio signal is less than a second preset level, and the noise cancellation is not performed on the input audio signal with the environmental noise level greater than or equal to the second preset level, so as to reduce the signal processing power consumption and the calculation amount.

Step S60, if the environmental noise level is less than the second preset level, executing the step of acquiring the input audio signal of the audio device and determining the basic gain of the noise cancellation filter of the audio device based on the input audio signal.

In this embodiment, if the environmental noise level is smaller than the second preset level, the noise cancellation is performed on the input audio signal, that is, the step of acquiring the input audio signal of the audio device and determining the base gain of the noise cancellation filter of the audio device based on the input audio signal is performed. In this embodiment, when it is determined that the environmental noise level is greater than or equal to the second preset level, that is, the environmental noise level is greater, noise cancellation is not performed on the input audio signal; noise cancellation is performed when the ambient noise level is less than a second preset level, i.e. the ambient noise level is small. Compared with noise elimination of the input audio signal under all signal noise levels, the embodiment can reduce the calculation amount and the power consumption of the signal processing system.

Further, in a possible implementation manner, the noise cancellation may be performed based on the signal volume of the input audio signal, and specifically, the process of performing the noise cancellation based on the signal volume of the input audio signal may be: acquiring an input audio signal of an audio device and determining an audio signal volume of the input audio signal; determining a base gain of a noise cancellation filter of the audio device based on the input audio signal; adjusting the basic gain based on the volume of the audio signal to obtain a filter gain, wherein the filter gain and the volume of the audio signal form a positive correlation; the input audio signal is processed by the filter gain to eliminate noise when the input audio signal is played.

In this embodiment, the step of adjusting the base gain based on the volume of the audio signal to obtain the filter gain includes: determining a target noise elimination coefficient corresponding to the volume of the audio signal from preset noise elimination coefficients corresponding to the volume of the plurality of signals respectively; and processing the basic gain through the target noise elimination coefficient to obtain the filter gain.

Further, in a possible implementation manner, noise cancellation may be performed based on the signal volume and the environmental noise level at the same time, in this implementation manner, the target noise cancellation coefficient obtained based on the environmental noise level may be processed according to the actual requirement, and after the target noise cancellation coefficient obtained based on the signal volume is processed, the base gain is processed based on the processed target noise cancellation coefficient to obtain the filter gain, which will not be described herein in detail.

In this embodiment, an environmental sound signal of an external environment where the audio device is located is obtained, and an environmental noise level of the environmental sound signal is determined; acquiring an input audio signal of an audio device, and determining a base gain of a noise cancellation filter of the audio device based on the input audio signal; adjusting the basic gain based on the environmental noise level to obtain a filter gain, wherein the filter gain and the environmental noise level form a negative correlation; the input audio signal of the audio device is processed by the filter gain to eliminate noise when the input audio signal is played.

The embodiment determines a filter gain for noise cancellation of the input audio signal based on the ambient noise level, wherein the filter gain is inversely related to the ambient noise level. That is, when the noise level is larger, the filter gain is smaller, the noise elimination degree of the input audio signal is smaller, and because the noise generated when the audio equipment plays the input audio signal is covered by the external noise when the noise level is larger, the noise generated when the input audio signal is played can not be heard by the user almost, so that the noise elimination effect can be ensured while the calculation amount and the power consumption of the signal processing system are reduced; the smaller the noise level is, the clearer and audible noise generated when the audio equipment plays the input audio signal is, at this time, the larger the gain of the filter is, so that the degree of eliminating the noise of the input audio signal is larger, the hearing of a user is improved, in sum, the embodiment realizes that the noise eliminating method is adapted to different environmental noises, so that the noise eliminating method can meet the requirements of different environmental noises, and the practicability of the noise eliminating method is improved.

Further, based on the above first embodiment, a second embodiment of the noise cancellation method of the present invention is proposed, and in this embodiment, the step S30 includes:

Step S301, determining a target noise elimination coefficient based on the environmental noise level and a preset mapping relation, wherein the preset mapping relation comprises corresponding relations between different signal noise levels and the target noise elimination coefficient;

in this embodiment, the correspondence between different signal noise levels and the target noise cancellation coefficient, that is, the preset mapping relationship, is preset. The preset signal noise level can be set according to actual requirements. Specifically, after the environmental noise level is determined, a target noise cancellation coefficient is determined based on the environmental noise level and a preset mapping relationship. Wherein the target noise cancellation coefficient has a correlation with the ambient noise level.

Step S302 processes the base gain through the target noise cancellation coefficient to obtain a filter gain.

In this embodiment, the filter gain is obtained by processing the basic gain with the target noise cancellation coefficient, the processing procedure of the basic gain with the target noise cancellation coefficient is not limited herein, and specifically, the filter gain obtained by processing may be set according to the form of the target noise cancellation coefficient and the form of the basic gain, where: the filter gain and the ambient noise level are inversely related.

In this embodiment, the specific process of processing the base gain for the target noise cancellation coefficient is not limited herein. Illustratively, in a possible implementation, when the target noise cancellation coefficient is greater than 0 and decreases with increasing signal noise level, in order for the filter gain to satisfy the negative correlation between the filter gain and the environmental noise level, the filter gain may be obtained by multiplying or adding the target noise cancellation coefficient by the base gain; in another possible embodiment, when the target noise cancellation coefficient is greater than 0 and increases with an increase in the signal noise level, in order for the filter gain to satisfy the negative correlation between the filter gain and the environmental noise level, the filter gain may be obtained by dividing the base gain by the target noise cancellation coefficient.

Further, in a possible implementation manner, the preset mapping relationship includes a first calculation formula and a second calculation formula, and the step S301 includes:

step S3011, if the environmental noise level is greater than or equal to a first preset level, calculating to obtain a target noise cancellation coefficient based on the environmental noise level and the first calculation formula, where the target noise cancellation coefficient calculated based on the first calculation formula is less than or equal to 1;

In this embodiment, the environmental noise level is classified into a large noise level greater than or equal to the first preset level and a non-large noise level less than the first preset level based on the first preset level set in advance. For an input audio signal under a non-large noise level, the noise elimination degree needs to be improved so as to improve the noise elimination effect, improve the signal purity when the input audio signal is played, and improve the user experience; for the input audio signal with large noise level, the noise elimination degree is reduced, so that the signal is stable when the input audio signal is played, the hearing of a user is improved, and the user experience is improved.

Specifically, if the environmental noise level is greater than or equal to the first preset level, determining that the input audio signal is a signal with a large noise level, and at this time, calculating based on the environmental noise level and the first calculation formula to obtain the target noise cancellation coefficient, so as to reduce the noise cancellation degree along with the increase of the environmental noise level, so as to avoid the situation that the input audio signal is unstable when played due to excessive noise cancellation degree. The specific formula of the first calculation formula is not limited herein, and may satisfy the condition that the target noise cancellation coefficient calculated based on the first calculation formula is less than or equal to 1, for example, in a possible embodiment, the first calculation formula may be: α=l/m, where α is a target noise cancellation coefficient, L is an ambient noise level, and m is a second preset level, where the second preset level is greater than the first preset level.

Step S3012, if the environmental noise level is less than the first preset level, calculating the target noise cancellation coefficient based on the environmental noise level and the second calculation formula, where the target noise cancellation coefficient calculated based on the second calculation formula is greater than 1.

If the environmental noise level is smaller than the first preset level, determining that the input audio signal is a signal with a small noise level, and calculating based on the environmental noise level and the second calculation formula to obtain a target noise elimination coefficient so as to improve the noise elimination degree, improve the noise elimination effect, improve the signal purity when the input audio signal is played, and improve the user experience. The specific formula of the second calculation formula is not limited herein, and may be satisfied if the target noise cancellation coefficient calculated based on the second calculation formula is greater than 1, for example, in a possible embodiment, the second calculation formula may be: α= (L/n) +b, where α is a target noise cancellation coefficient, L is an ambient noise level, n is a first preset level, and b is a preset parameter, and the value is greater than or equal to 1.

Further, in a possible implementation manner, the preset mapping relationship includes preset noise cancellation coefficients corresponding to the signal noise levels, and the step S301 includes:

Step S3013, determining a target noise cancellation coefficient corresponding to the environmental noise level from preset noise cancellation coefficients corresponding to each of a plurality of signal noise levels;

in this embodiment, a plurality of signal noise levels are preset, and a preset noise cancellation coefficient is preset for each signal noise level.

Specifically, after the environmental noise level is determined, a target noise cancellation coefficient corresponding to the environmental noise level is determined from among preset noise cancellation coefficients corresponding to each of the plurality of signal noise levels.

In this embodiment, the preset noise cancellation coefficient may be determined based on an acoustic parameter of the audio device, where the acoustic parameter includes a structural parameter of the audio device and/or a signal processing parameter of the audio device, and the preset noise cancellation coefficient is determined based on the acoustic parameter of the audio device, so that each preset noise cancellation coefficient is more consistent with a structure of a speaker, so that when an input audio signal is processed based on a target noise cancellation coefficient, noise caused by a device structure or a processing parameter of the audio device may be cancelled, thereby further improving a noise cancellation degree of the audio device. In particular, the structural parameters of the audio device may include: the structural parameters of the speaker and/or the housing structural parameters of the audio device may specifically be module parameters of a DRC (Dynamic Range Control ) module, for example, gain, ratio, attach time (time required for the Gain value to take effect from the beginning to the end to stabilize), etc., which may specifically be set according to actual requirements, and is not limited herein.

The specific process of determining the preset noise elimination coefficient corresponding to different signal noise levels may be: determining a plurality of signal noise levels according to preset basic noise elimination coefficients based on acoustic parameters, wherein the basic noise elimination coefficients can be set according to actual requirements; and for any signal noise level in the signal noise levels, adjusting the basic noise elimination coefficient based on the acoustic parameter to obtain a preset noise elimination coefficient corresponding to the signal noise level. The adjustment direction of the basic noise elimination coefficient depends on the specific acoustic properties of the acoustic parameters, and for the acoustic parameters with larger values, which lead to larger noise of the input audio signal, the basic noise elimination coefficient is adjusted in the same direction as the acoustic parameters, namely, as the values of the acoustic parameters are increased, the basic noise elimination coefficient is increased to obtain a preset elimination coefficient, and at the moment, the preset elimination coefficient and the acoustic parameters form a positive correlation; and for the acoustic parameters with larger values and smaller input audio signals, reversely adjusting the basic noise elimination coefficient, namely, reducing the basic noise elimination coefficient along with the increase of the values of the acoustic parameters to obtain a preset elimination coefficient, wherein the preset elimination coefficient and the acoustic parameters form a negative correlation. The acoustic parameters on which the basic noise cancellation coefficients are adjusted are not limited here.

For example, in a possible implementation manner, when the acoustic parameter includes a structural parameter of the speaker and specifically includes a maximum design displacement of the speaker diaphragm, the smaller the maximum design displacement is, the more easily the transient sound source impact causes the excessive displacement of the diaphragm to bottom out, and the smaller the maximum design displacement is, the larger the preset noise elimination coefficient is, so that the larger the filter gain is.

In another possible implementation, when the acoustic parameter includes a structural parameter of the speaker and specifically includes a size of a speaker cavity, the cavity is smaller, and noise is easily generated by rubbing under the impact of a low-frequency or large-amplitude sound source, at this time, in order to reduce the noise, the smaller the size of the cavity, the larger the preset noise elimination coefficient is, so that the larger the gain of the filter is, thereby improving the degree of noise elimination.

In another possible implementation manner, when the acoustic parameter includes a structural parameter of the speaker and specifically includes BL (single force coefficient), the larger the BL coefficient, the larger the displacement of the diaphragm under the impact of the low-frequency or large-amplitude sound source, the more the noise at the bottom of the diaphragm is likely to be increased, at this time, in order to reduce the noise, the larger the BL coefficient may be set, the larger the preset noise cancellation coefficient is set, so that the larger the gain of the filter is, thereby improving the degree of noise cancellation.

In another possible implementation manner, when the acoustic parameter includes a shell structural parameter of the audio device and specifically includes a size of an acoustic hole of the audio device, the smaller the acoustic hole, the easier the acoustic hole is rubbed to generate airflow noise when the acoustic wave enters and exits, at this time, in order to reduce the noise, the smaller the size of the acoustic hole, the larger the preset noise elimination coefficient can be set, so that the larger the gain of the filter is.

In another possible embodiment, when the acoustic parameters include signal processing parameters and specifically include Gain and/or Ratio in the DRC module, the smaller the DRC module parameters, the more likely the noise is generated when there is an impact of a transient large signal, at this time, in order to reduce the noise, the smaller the DRC module parameters, the larger the preset noise cancellation coefficient may be set, so that the larger the filter Gain is, thereby improving the degree of noise cancellation.

In another possible implementation, when the acoustic parameter includes a signal processing parameter and specifically includes an attach time in the DRC module, the larger the attach time is set, the longer the filter gain takes effect to be stable, that is, the longer the time for noise cancellation, at this time, in order to improve the effect of noise cancellation, the larger the attach time is set, the larger the preset noise cancellation coefficient is set, so that the larger the filter gain is, thereby improving the degree of noise cancellation.

Further, in a possible embodiment, the adjustment of the basic noise cancellation coefficient may be performed by using a plurality of acoustic parameters as adjustment bases, and in this embodiment, since the degree of influence of each acoustic parameter on the noise of the input audio signal may be different, the degree of adjustment of the basic noise cancellation coefficient based on each acoustic parameter may be different.

In the embodiment, the target noise elimination coefficient is determined based on the environmental noise level and a preset mapping relation, wherein the preset mapping relation comprises the corresponding relation between different signal noise levels and the target noise elimination coefficient; and processing the basic gain through the target noise elimination coefficient to obtain the filter gain. The embodiment realizes that the filter gain for noise cancellation of the input audio signal is determined according to the environmental noise level, wherein the filter gain and the environmental noise level are in a negative correlation. That is, when the noise level is larger, the filter gain is smaller, the noise elimination degree of the input audio signal is smaller, and because the noise generated when the audio equipment plays the input audio signal is covered by the external noise when the noise level is larger, the noise generated when the input audio signal is played can not be heard by the user almost, so that the noise elimination effect can be ensured while the calculation amount and the power consumption of the signal processing system are reduced; the smaller the noise level is, the clearer and audible noise generated when the audio equipment plays the input audio signal is, at this time, the larger the gain of the filter is, so that the degree of eliminating the noise of the input audio signal is larger, the hearing of a user is improved, in sum, the embodiment realizes that the noise eliminating method is adapted to different environmental noises, so that the noise eliminating method can meet the requirements of different environmental noises, and the practicability of the noise eliminating method is improved.

Illustratively, in one possible implementation, referring to fig. 3, the specific flow of noise cancellation may be:

the ambient noise L is detected (i.e., an ambient sound signal of the external environment in which the audio device is located is acquired and an ambient noise level of the ambient sound signal is determined).

An ambient noise threshold m (i.e., a second preset level) that enables noise cancellation is set, and a demarcation value n (i.e., a first preset level) for stationary and clean modes, where n < m. The magnitude of the ambient noise L and the threshold value m is determined (i.e., whether the ambient noise level is detected to be less than or equal to a second preset level).

If L is greater than or equal to m, noise cancellation is not enabled, because noise occurring when the input audio signal is played is often masked by large background noise and is inaudible at this time, so that noise cancellation may not be enabled to achieve the purpose of saving the system calculation amount and power consumption (i.e., if the environmental noise level is greater than or equal to the second preset level, noise cancellation is not enabled).

If L < m, then noise cancellation is enabled (i.e., if the ambient noise level is less than the second preset level, then the steps of acquiring the input audio signal of the audio device and determining the base gain of the noise cancellation filter of the audio device based on the input audio signal) are performed as follows:

Performing distortion feature extraction on the input audio signal (i.e., extracting distortion features of the input audio signal);

performing distortion recognition on the noise in the input audio signal based on the extracted distortion feature (i.e., performing noise recognition on the input audio signal based on the distortion feature to obtain a noise recognition result);

and (3) performing distortion degree analysis: generating a default filter gain and a filter coefficient alpha (i.e., determining a base gain of a noise cancellation filter of the audio device based on the noise identification result, adjusting the base gain based on the ambient noise level to obtain a filter gain);

it is detected whether the ambient noise L is smaller than the demarcation value n. If n is less than or equal to L < m, the operation is in a stable mode, and alpha=L/m is defined; if the environmental noise 0< L < n, the operation is in a pure mode, and alpha= (L/n) +b is defined (i.e., if the environmental noise level is greater than or equal to a first preset level, a target noise cancellation coefficient is calculated based on the environmental noise level and the first calculation formula, wherein the target noise cancellation coefficient calculated based on the first calculation formula is less than or equal to 1, and if the environmental noise level is less than the first preset level, a target noise cancellation coefficient is calculated based on the environmental noise level and the second calculation formula, wherein the target noise cancellation coefficient calculated based on the second calculation formula is greater than 1).

Adjusting the filter gain: the default filter gain is multiplied by a and then distortion control is performed (i.e., the base gain is adjusted based on the ambient noise level to obtain a filter gain; the input audio signal is processed through the filter gain to eliminate noise when the input audio signal is played).

Further, in a possible implementation manner, noise elimination can be performed based on the volume of the audio signal, and the specific process can be as follows: acquiring the system volume selected by a user as the audio signal volume; setting a threshold value m for starting an algorithm; judging whether the system volume level selected by the user is greater than the set m, if the system volume level selected by the user is less than the set m, not eliminating noise, and closing the noise elimination algorithm module to directly output the sound signal so as to save the calculated amount and the power consumption of the system; if the system volume level selected by the user is greater than or equal to m, starting a noise elimination algorithm module to eliminate noise.

Further, in a possible implementation manner, the input audio signal may be processed by combining the audio signal volume and the ambient noise level, and the specific values of m and m1 are set according to the actual requirement, so as to determine to start the specific scene of performing noise cancellation based on the audio signal volume and/or performing noise cancellation based on the ambient noise level, which may be specifically set according to the actual requirement, for example, in an implementation manner, m may be set to 3 and m1 may be set to 5, where if the ambient noise level is greater than 5 and the audio signal volume is less than 3, the noise cancellation may not be started; if the ambient noise level is greater than 5 and the audio signal volume is greater than 3, then the mode for noise cancellation based on the audio signal volume may be turned on and the mode for noise cancellation based on the ambient noise level may be turned off.

In addition, an embodiment of the present invention further provides a noise cancellation device, referring to fig. 4, where the noise cancellation device includes:

an acquisition module 10, configured to acquire an environmental sound signal of an external environment where an audio device is located, and determine an environmental noise level of the environmental sound signal;

a determining module 20, configured to obtain an input audio signal of the audio device, and determine a base gain of a noise cancellation filter of the audio device based on the input audio signal;

an adjusting module 30, configured to adjust the base gain based on the environmental noise level to obtain a filter gain, where the filter gain has a negative correlation with the environmental noise level;

the noise cancellation module 40 is configured to process the input audio signal through the filter gain to cancel noise when the input audio signal is played.

Further, the adjusting module 30 is further configured to:

Further, the preset mapping relationship includes a first calculation formula and a second calculation formula, and the adjustment module 30 is further configured to:

Further, the preset mapping relationship includes preset noise cancellation coefficients corresponding to the signal noise levels, and the adjustment module 30 is further configured to:

Further, the adjusting module 30 is further configured to:

Further, the determining module 20 is further configured to:

Further, the noise cancellation device further includes a detection module for:

Embodiments of the noise cancellation device of the present invention may refer to embodiments of the noise cancellation method of the present invention, and will not be described herein.

In addition, an embodiment of the present invention also proposes a computer-readable storage medium having stored thereon a noise cancellation program which, when executed by a processor, implements the steps of a noise cancellation method as described below.

Embodiments of the noise cancellation apparatus and the computer-readable storage medium of the present invention may refer to embodiments of the noise cancellation method of the present invention, and will not be described herein.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The foregoing embodiment numbers of the present invention are merely for the purpose of description, and do not represent the advantages or disadvantages of the embodiments.

From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) comprising instructions for causing a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the method according to the embodiments of the present invention.

The foregoing description is only of the preferred embodiments of the present invention, and is not intended to limit the scope of the invention, but rather is intended to cover any equivalents of the structures or equivalent processes disclosed herein or in the alternative, which may be employed directly or indirectly in other related arts.

Claims

1. A method of noise cancellation, the method comprising the steps of:

2. The method of noise cancellation of claim 1 wherein said step of adjusting said base gain based on said ambient noise level to obtain a filter gain comprises:

3. The method of noise cancellation according to claim 2, wherein the predetermined mapping relation includes a first calculation formula and a second calculation formula, and the step of determining the noise cancellation coefficient based on the ambient noise level and the predetermined mapping relation includes:

4. The method of noise cancellation according to claim 2, wherein the predetermined mapping relation includes predetermined noise cancellation coefficients corresponding to each of a plurality of signal noise levels, and the step of determining the target noise cancellation coefficients based on the environmental noise level and the predetermined mapping relation includes:

5. The method of noise cancellation according to claim 4, wherein prior to said step of determining a target noise cancellation coefficient corresponding to said ambient noise level from among preset noise cancellation coefficients corresponding to each of a plurality of signal noise levels, further comprising:

6. The method of noise cancellation of any one of claim 1, wherein the step of determining a base gain of a noise cancellation filter of the audio device based on the input audio signal comprises:

7. The noise cancellation method of any one of claims 1 to 6, wherein after the step of determining the ambient noise level of the ambient sound signal, further comprising:

8. A noise cancellation device, characterized in that the noise cancellation device comprises:

9. A noise cancellation device, characterized in that the noise cancellation device comprises: memory, a processor and a noise cancellation program stored on the memory and executable on the processor, which when executed by the processor implements the steps of the noise cancellation method according to any one of claims 1 to 7.

10. A computer-readable storage medium, wherein a noise cancellation program is stored on the computer-readable storage medium, which when executed by a processor, implements the steps of the noise cancellation method according to any one of claims 1 to 7.