WO2023045130A1

WO2023045130A1 - Noise reduction method and apparatus, earphone device, and storage medium

Info

Publication number: WO2023045130A1
Application number: PCT/CN2021/138976
Authority: WO
Inventors: 曲征
Original assignee: 歌尔科技有限公司
Priority date: 2021-09-24
Filing date: 2021-12-17
Publication date: 2023-03-30
Also published as: CN113676815A; CN113676815B

Abstract

The present application discloses a noise reduction method and apparatus, an earphone device, and a storage medium. The method is applied to an earphone device; the earphone device comprises an active noise reduction circuit, a loudspeaker, a sound outlet hole, and a feedback microphone array; the feedback microphone array comprises multiple feedback microphones; a distribution plane of the feedback microphone array is perpendicular to a connecting line between the loudspeaker and the sound outlet hole, and the center of the feedback microphone array is located on the connecting line. The method comprises: obtaining first noise signals respectively detected by feedback microphones; performing noise reduction processing on the first noise signals by means of an active noise reduction circuit to obtain a noise cancellation signal corresponding to an average signal of the first noise signals; and playing the noise cancellation signal by means of a loudspeaker. According to the present application, the cancellation of the noise at the center of the feedback microphone array can be equivalently implemented, and thus the noise at a human ear can also be cancelled.

Description

Noise reduction method, device, earphone device and storage medium

This application claims the priority of the Chinese patent application with the application number 202111123005.X and the application title "Noise Reduction Method, Device, Headphone Equipment, and Storage Medium" filed with the China Patent Office on September 24, 2021, the entire contents of which are incorporated by reference incorporated in this application.

technical field

The present application relates to the technical field of earphones, and in particular to a noise reduction method, device, earphone equipment and a storage medium.

Background technique

With the continuous development and maturity of active noise reduction technology, users have higher and higher requirements for the active noise reduction function of headphones. At present, the principle of feedback noise-cancelling headphones is to set a feedback microphone inside the earmuffs to pick up the noise inside the earmuffs, and to process the noise through an algorithm to form a reverse sound wave of the noise to offset the noise at the feedback noise-cancelling headphones, thereby Active cancellation of noise is achieved. In the principle of this technology, the feedback microphone is used to replace the human ear to pick up the noise. If the noise at the feedback microphone is eliminated, it is considered that the noise at the human ear is also eliminated. However, when wearing headphones, there is a certain distance between the feedback microphone and the human ear. When the noise at the feedback microphone is eliminated, the noise at the human ear may not be completely eliminated. Especially for high-frequency noise, a slight distance change will bring about phase The huge change of , resulting in a large difference between the estimated noise reduction amount and the measured value in the high frequency band.

Contents of the invention

The main purpose of this application is to provide a noise reduction method, device, earphone device and storage medium, aiming to solve the problem that there is a distance between the feedback microphone and the human ear, and the technology that the noise at the feedback microphone cannot completely eliminate the noise at the human ear question.

In order to achieve the above purpose, the present application provides a noise reduction method, which is applied to a headphone device, and the headphone device includes an active noise reduction circuit, a speaker, a sound hole and a feedback microphone array, and the feedback microphone array includes A plurality of feedback microphones, the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is that the distribution plane of the feedback microphone array is perpendicular to the speaker and the outlet The line between the sound holes, and the center of the feedback microphone array is on the line, and the noise reduction method comprises the following steps:

acquiring first noise signals respectively detected by each of the feedback microphones;

performing noise reduction processing on each of the first noise signals through the active noise reduction circuit to obtain a noise reduction signal corresponding to an average signal of each of the first noise signals;

The noise-canceling signal is played through the loudspeaker.

Optionally, the step of performing noise reduction processing on each of the first noise signals through the active noise reduction circuit to obtain a denoising signal corresponding to an average signal of each of the first noise signals includes:

averaging each of the first noise signals to obtain an average signal;

Inputting the average signal into the active noise reduction circuit for noise reduction processing to obtain a denoising signal corresponding to the average signal.

Optionally, before the step of acquiring the first noise signals respectively detected by each of the feedback microphones, it may further include:

Acquiring test noise signals detected by each of the feedback microphones, wherein the test noise signal is a signal detected by each of the feedback microphones after playing preset test noise through the speaker;

averaging each of the test noise signals to obtain an average test signal;

calculating an acoustic transfer function from the loudspeaker to the center of the feedback microphone array according to the average test signal;

setting filter coefficients in the active noise reduction circuit according to the acoustic transfer function;

The step of inputting the average signal into the active noise reduction circuit to perform noise reduction processing, and obtaining a denoising signal corresponding to the average signal includes:

Inputting the average signal into the active noise reduction circuit, performing noise reduction processing based on the filter coefficients, to obtain a denoising signal corresponding to the average signal.

Optionally, the active noise reduction circuit includes an active noise reduction branch corresponding to each of the feedback microphones, and the active noise reduction circuit performs noise reduction processing on each of the first noise signals to obtain the same The step of denoising signal corresponding to the average signal of each said first noise signal comprises:

Input each of the first noise signals into the corresponding active noise reduction branch to perform noise reduction processing, and obtain branch noise reduction signals corresponding to each of the first noise signals;

The denoising signals of each of the branches are averaged, and the result is used as a denoising signal corresponding to the average signal of each of the first noise signals.

calculating an acoustic transfer function from the loudspeaker to the corresponding feedback microphone according to each of the test noise signals;

Setting the branch filter coefficients in the corresponding active noise reduction branch according to each of the acoustic transfer functions;

The step of inputting each of the first noise signals into the corresponding active noise reduction branch for noise reduction processing, and obtaining the branch denoising signals corresponding to each of the first noise signals includes:

Each of the first noise signals is input to a corresponding active noise reduction branch, and noise reduction processing is performed based on the corresponding branch filter coefficients to obtain branch denoising signals corresponding to each of the first noise signals.

Optionally, when the distribution position of the feedback microphone array meets the position condition after error compensation, the noise cancellation signals of each of the branches are averaged, and the result is used as the result of each of the first noise signals The step of averaging the denoised signal corresponding to the signal includes:

Acquiring weights corresponding to each of the feedback microphones, wherein the weights are set in advance according to the error of the distribution position of the feedback microphone array relative to the position condition;

Performing a weighted average on each of the branch denoising signals according to the corresponding weight, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.

Optionally, the active noise reduction circuit includes a feedforward active noise reduction circuit and a feedback active noise reduction circuit, and the earphone device further includes a feedforward microphone, and each of the first A noise signal is subjected to noise reduction processing, and the step of obtaining a noise removal signal corresponding to the average signal of each of the first noise signals includes:

acquiring a second noise signal detected by the feedforward microphone;

performing noise reduction processing on the second noise signal through the feedforward active noise reduction circuit to obtain a feedforward noise reduction signal;

performing noise reduction processing on each of the first noise signals through the feedback active noise reduction circuit to obtain a feedback denoising signal corresponding to an average signal of each of the first noise signals;

adding the feedforward denoising signal and the feedback denoising signal, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.

In order to achieve the above purpose, the present application also provides a noise reduction device, the noise reduction device is deployed in the earphone device, the earphone device includes an active noise reduction circuit, a speaker, a sound hole and a feedback microphone array, and the feedback microphone array It includes a plurality of feedback microphones, the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is that the distribution plane of the feedback microphone array is perpendicular to the speaker and the The connection between the sound holes, and the center of the feedback microphone array is on the connection, and the noise reduction device includes:

An acquisition module, configured to acquire the first noise signals respectively detected by each of the feedback microphones;

A noise reduction module, configured to perform noise reduction processing on each of the first noise signals through the active noise reduction circuit, to obtain a noise reduction signal corresponding to an average signal of each of the first noise signals;

A playback module, configured to play the noise-canceling signal through the loudspeaker.

In order to achieve the above object, the present application also provides an earphone device, the earphone device includes an active noise reduction circuit, a loudspeaker, a sound outlet and a feedback microphone array, the feedback microphone array includes a plurality of feedback microphones, and the feedback microphone array The distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is that the distribution plane of the feedback microphone array is perpendicular to the connection line between the speaker and the sound outlet, And the center of the feedback microphone array is on the connection line, the earphone device also includes a memory, a processor, and a noise reduction program stored on the memory and operable on the processor, the noise reduction When the program is executed by the processor, the steps of the above-mentioned noise reduction method are realized.

In addition, in order to achieve the above purpose, the present application also proposes a computer-readable storage medium, on which a noise reduction program is stored, and when the noise reduction program is executed by a processor, the above-mentioned noise reduction is realized. method steps.

In this application, by setting the feedback microphone array in the earphone device, the feedback microphone array includes a plurality of feedback microphones, and the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is the feedback microphone array The distribution plane is perpendicular to the line between the loudspeaker and the sound outlet, and the center of the feedback microphone array is on the line; each first noise signal detected by each feedback microphone is processed by the active noise reduction circuit in the earphone device The noise reduction processing is to obtain the noise cancellation signal corresponding to the average signal of each first noise signal, and the noise cancellation signal at the center of the feedback microphone array can be equivalently canceled by playing the noise cancellation signal through the loudspeaker, and then the noise at the human ear can be realized. Noise is also canceled out.

Description of drawings

FIG. 1 is a schematic flow chart of the first embodiment of the noise reduction method of the present application;

FIG. 2 is a schematic diagram of a feedback noise reduction principle involved in an embodiment of the present application;

FIG. 3 is a schematic diagram of a noise transmission path of an in-ear earphone according to an embodiment of the present application;

Fig. 4 is a schematic diagram of the setting position of the feedback microphone of an in-ear earphone according to the embodiment of the present application;

FIG. 5 is a schematic diagram of functional modules of a preferred embodiment of the noise reduction device of the present application.

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

Detailed ways

It should be understood that the specific embodiments described here are only used to explain the present application, and are not intended to limit the present application.

Referring to FIG. 1 , FIG. 1 is a schematic flowchart of a first embodiment of a noise reduction method of the present application.

The embodiment of the present application provides an embodiment of the noise reduction method. It should be noted that although the logic sequence is shown in the flow chart, in some cases, the steps shown or described can be executed in a different order than here. A step of. The noise reduction method of this application is applied to the earphone device. The earphone device can include one or two earphones. Since the noise reduction method of the two earphones is the same, the following is for the convenience of description. By default, the earphone device includes one earphone as an example for implementation. example. In this embodiment, the noise reduction method includes:

Step S10, acquiring first noise signals respectively detected by each of the feedback microphones;

At present, the technical principle of feedback active noise reduction (also known as feedback noise reduction) is shown in Figure 2. There is a feedback microphone (FB mic) inside the earmuffs, and the noise inside the earmuffs (also called noise noise reduction) is picked up by the feedback microphone. signal), the noise is processed by an algorithm to form an anti-phase sound wave for offsetting. d(t) is the initial noise inside the earmuff, c(t) is the anti-phase sound wave processed by the algorithm, and e(t) is the residual noise after cancellation. Feedback noise reduction uses the feedback microphone instead of the human ear to pick up noise, that is to say, the feedback noise reduction will eliminate the noise at the feedback microphone, but it is unknown whether it can be eliminated at the human ear. Figure 3 shows a simplified diagram of an in-ear earphone (take in-ear earphones as an example, but other types of earphones can also be used), the far right is the sound hole of the earphone, which will go deep into the ear canal when actually worn. Assuming that the noise enters the ear from the front sound hole, four paths a, b, c, and d are given in Figure 3, a is the path from the noise to the feedback microphone, b is the path from the noise to the human ear, and c is the path from the speaker to the feedback microphone d is the path from the loudspeaker to the human ear. According to the feedback noise reduction theory, the noise of path a and path c is equal-amplitude anti-phase cancellation at the feedback microphone. If you want equal-amplitude anti-phase cancellation noise at the human ear If so, b-a=d-c needs to be satisfied (where a, b, c, and d represent distances), that is, if and only when b-a=d-c, the noise reduction result at the feedback microphone is consistent with the noise reduction result at the human ear of. The relative position of the feedback microphone, the loudspeaker and the human ear is fixed, and d-c is a constant value, but as the position of the noise source changes, the value of b-a changes, resulting in situations where b-a is not equal to d-c, and the position of the human ear noise will not necessarily be eliminated. Especially for high-frequency signals with short wavelengths, the small difference between b and a will bring about a huge change in phase, which will eventually lead to a large difference between the estimated noise reduction amount in the high-frequency band and the measured value. In order to solve the above problems, the feedback microphone is arranged on the connection line between the speaker and the sound outlet, which basically satisfies b-a=d-c. However, setting the feedback microphone at this position will block the sound channel of the speaker and affect the sound quality.

In view of this, a noise reduction method is proposed in this embodiment, aiming at setting multiple feedback microphones in the earphone device, by limiting the distribution positions of the multiple feedback microphones to meet certain position conditions, and by designing The summary calculation method of the output signal makes the functions of the multiple feedback microphones equivalent to the functions of the feedback microphones arranged on the connection line between the loudspeaker and the sound outlet, that is, makes it equivalent to satisfying b-a=d-c.

Specifically, the earphone device includes an active noise reduction circuit, a speaker, a sound outlet, and a feedback microphone array, the feedback microphone array includes a plurality of feedback microphones, and the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, The location condition is that the distribution plane of the feedback microphone array is perpendicular to the line between the loudspeaker and the sound outlet, and the center of the feedback microphone array is on the line.

Among them, in a specific implementation, due to space constraints and other reasons in the earphone device, it may not be possible to set a feedback microphone array whose distribution position strictly meets the position condition, that is, the distribution position of the feedback microphone array is the same as the feedback microphone array that meets the position condition. There is a certain error in the distribution position of , and error compensation refers to the measurement of the error in advance, and in the subsequent noise reduction process, the measured error is used to compensate the output signal of the feedback microphone array (usually the detected noise signal), so as to The output signal of the compensated feedback microphone array is equivalent to the output signal of the feedback microphone array (hereinafter referred to as the standard microphone array) that meets the position condition. For example, by measuring the relative pose between the distribution position of the actual feedback microphone array and the distribution position of the standard microphone array, and testing the actual feedback microphone array through the test signal, it is calculated according to the relative pose according to the test result that The conversion formula for converting the output signal of the actual feedback microphone array into the output signal of the standard microphone array. In the subsequent noise reduction process, the output signal of the actual feedback microphone array is converted according to the conversion formula and then participates in the noise reduction process.

In one embodiment, when the feedback microphone array includes two feedback microphones, as shown in FIG. 4 , the two feedback microphones may be symmetrically arranged on both sides of the sound outlet.

When the active noise reduction function of the earphone device is turned on during use, the noise signal is detected by each feedback microphone of the feedback microphone array (hereinafter referred to as the first noise signal for distinction); since there are multiple feedback microphones, each feedback microphone detects the noise signal separately. noise signal, so there are multiple first noise signals. It should be noted that, when the speaker is playing audio, the earphone device may remove the audio signal played by the speaker from the sound signals detected by the feedback microphone, and the remaining part may be used as the first noise signal.

Step S20, performing noise reduction processing on each of the first noise signals through the active noise reduction circuit to obtain a noise reduction signal corresponding to the average signal of each of the first noise signals;

For the first noise signals detected by each feedback microphone, the earphone device performs noise reduction processing on each first noise signal through an active noise reduction circuit to obtain a noise reduction signal corresponding to an average signal of each first noise signal. The average signal is a signal obtained by averaging the first noise signals, and the denoising signal corresponding to the average signal may include a signal generated through denoising processing for canceling the average signal. In this embodiment, the purpose is to obtain the denoising signal corresponding to the average signal, and the order of the two steps of averaging and denoising is not limited; for example, the specific implementation method may be to average each first noise signal , and then perform noise reduction processing on the average signal to directly obtain the denoising signal corresponding to the average signal, or firstly perform denoising processing on each first noise signal, and then average the results obtained by denoising processing to indirectly obtain the average signal Corresponding denoising signal.

The active noise reduction circuit can be a feedback active noise reduction circuit or a hybrid active noise reduction circuit, that is, it includes a feedback active noise reduction circuit and a feedforward active noise reduction circuit. The circuit design can be based on feedback or hybrid The design method is based on the design method of the active noise reduction circuit, which is not limited in this embodiment. The specific process of denoising the noise signal through the active noise reduction circuit to obtain the denoising signal can also refer to the principle of the existing active noise reduction circuit, and will not be described in detail here.

In one embodiment, when the active noise reduction circuit is a feedback active noise reduction circuit, the earphone device can perform noise reduction processing on each first noise signal through the feedback active noise reduction circuit to obtain the average signal of each first noise signal The corresponding feedback denoising signal is the final denoising signal.

Further, in one embodiment, when the active noise reduction circuit is a hybrid active noise reduction circuit, that is, when it includes a feedforward active noise reduction circuit and a feedback active noise reduction circuit, the earphone device also includes a feedforward microphone, so Said step S20 comprises:

Step a, acquiring a second noise signal detected by the feedforward microphone;

The feed-forward microphone is generally placed outside the earmuffs to pick up noise before the feedback microphone and the human ear. When the active noise reduction function of the earphone device is turned on during use, a noise signal (hereinafter referred to as a second noise signal for distinction) is detected through a feed-forward microphone.

Step b, performing noise reduction processing on the second noise signal through the feedforward active noise reduction circuit to obtain a feedforward noise reduction signal;

For the second noise signal detected by the feedforward microphone, the earphone device performs noise reduction processing on the second noise signal through a feedforward active noise reduction circuit to obtain a feedforward noise reduction signal, which is used to offset the second noise Signal. It should be noted that, in this embodiment, the specific process of noise reduction processing by the feedforward active noise reduction circuit will not be described in detail here, and the existing feedforward active noise reduction circuit can be referred to.

Step c, performing noise reduction processing on each of the first noise signals through the feedback active noise reduction circuit to obtain a feedback denoising signal corresponding to an average signal of each of the first noise signals;

The earphone device performs noise reduction processing on each of the first noise signals through a feedback active noise reduction circuit to obtain a feedback noise reduction signal corresponding to an average signal of each first noise signal. Specifically, the first noise signals may be averaged before performing the noise reduction processing, or the first noise signals may be respectively subjected to noise reduction processing before the noise reduction signals are averaged. It should be noted that, in this embodiment, the specific process of performing noise reduction processing through the feedback active noise reduction circuit will not be described in detail here, and the existing feedback active noise reduction circuit can be referred to.

Step d, adding the feedforward denoising signal and the feedback denoising signal, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.

After obtaining the feedforward denoising signal and the feedback denoising signal, add the two denoising signals together, and use the added signal as the denoising signal corresponding to the average signal of each first noise signal, that is, add The resulting signal is played through a loudspeaker. It can be understood that the feedforward noise cancellation signal is used to cancel the first noise signal, and the second noise signal picked up at the feedback microphone after cancellation is residual noise, and the feedback noise cancellation signal is used to cancel the noise picked up at the feedback microphone. The second noise signal, so as to achieve a better noise reduction effect through hybrid noise reduction.

Step S30, playing the noise-canceling signal through the loudspeaker.

After processing the noise-canceling signal, the earphone device plays the noise-canceling signal through the loudspeaker. Since the distribution plane of the feedback microphone array (or the feedback microphone array after error compensation) is perpendicular to the line between the loudspeaker and the sound outlet, and the center of the feedback microphone array is on the line, each of the feedback microphone arrays The average signal of the first noise signal detected by the feedback microphone can be regarded as the noise signal detected at the center of the feedback microphone array, and the denoising signal corresponding to the average signal obtained through the noise reduction process can be regarded as the noise signal for the feedback microphone The denoising signal of the noise signal at the center of the array, and then by playing the denoising signal, it is equivalent to canceling the noise signal at the center of the feedback microphone array; and because the center of the feedback microphone array is on the connecting line between the speaker and the sound outlet , so that b-a=d-c can be satisfied, so that when the noise signal at the center is canceled out, the noise signal at the human ear can also be canceled out.

In this embodiment, by setting the feedback microphone array in the earphone device, the feedback microphone array includes a plurality of feedback microphones, and the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is feedback The distribution plane of the microphone array is perpendicular to the connection line between the loudspeaker and the sound outlet, and the center of the feedback microphone array is on the connection line; each first noise detected by each feedback microphone is detected by the active noise reduction circuit in the earphone device. The signal is subjected to denoising processing to obtain the denoising signal corresponding to the average signal of each first noise signal, and the noise denoising signal at the center of the feedback microphone array can be effectively canceled by playing the denoising signal through the loudspeaker. The noise is also canceled out.

Further, based on the first embodiment above, a second embodiment of the noise reduction method of the present application is proposed. In this embodiment, the step S20 includes:

Step S201, averaging each of the first noise signals to obtain an average signal;

Step S202, inputting the average signal into the active noise reduction circuit for noise reduction processing to obtain a denoising signal corresponding to the average signal.

In this embodiment, for the first noise signals detected by each feedback microphone, the earphone device first averages the first noise signals to obtain an average signal. The method of averaging the noise signal can refer to the existing method of signal averaging, and will not be described in detail here. After the average signal is obtained, the average signal is input into the active noise reduction circuit for noise reduction processing.

When the active noise reduction circuit is a feedback active noise reduction circuit, the headphone device averages the first noise signals and inputs the average signal into the feedback active noise reduction circuit for noise reduction processing to obtain a feedback noise reduction signal corresponding to the average signal, Play the feedback denoise signal through the speaker as the final denoise signal. The filter coefficients of the feedback filter in the feedback active noise reduction circuit can be designed by testing in advance, and the design method can refer to the existing feedback filter design method, wherein the output signal of the feedback microphone (the detected noise signal ), the output signals of each feedback microphone can be averaged before participating in the filter design.

When the active noise reduction circuit is a hybrid active noise reduction circuit, that is, when it includes a feedforward active noise reduction circuit and a feedback active noise reduction circuit, the earphone device detects the second noise signal through the feedforward microphone, and converts the second noise signal Input the feedforward active noise reduction circuit for noise reduction processing to obtain the feedforward noise reduction signal; average the first noise signal detected by each feedback microphone to obtain the average signal input feedback active noise reduction circuit for noise reduction processing, and obtain The feedback denoising signal corresponding to the average signal; the result obtained by adding the feedforward denoising signal and the feedback denoising signal is used as the denoising signal corresponding to the average signal of each first noise signal, that is, the result obtained by adding Play through speakers. Similarly, the filter coefficients of the feedforward filter in the feedforward active noise reduction circuit and the feedback filter in the feedback active noise reduction circuit can be designed through pre-testing, and the design method can refer to the existing feedforward filter And the design method of the feedback filter, wherein when the output signal (detected noise signal) of the feedback microphone is needed, the output signals of each feedback microphone can be averaged and then participate in the filter design.

Further, in one embodiment, before the step S10, it also includes:

Step A10, acquiring test noise signals detected by each of the feedback microphones respectively, wherein the test noise signal is a signal detected by each of the feedback microphones after playing preset test noise through the speaker;

The filter coefficients in the ANC circuit can be set by playing test noise and calculating the acoustic transfer function. Specifically, a section of test noise (hereinafter referred to as test noise) can be preset in the earphone device, the test noise is played through the speaker in the earphone device, and the noise signal is detected by each feedback microphone, and the noise signal is called the test noise Signal.

Step A20, averaging each of the test noise signals to obtain an average test signal;

Step A30, calculating an acoustic transfer function from the loudspeaker to the center of the feedback microphone array according to the average test signal;

The average test signal is obtained by averaging the test noise signals, which can be regarded as the noise signal picked up by the microphone placed at the center of the feedback microphone array (the microphone is not actually set at this position). According to the average test signal, the acoustic transfer function from the loudspeaker to the center of the feedback microphone array can be calculated, and the acoustic transfer function reflects the transfer relationship between the noise signal played by the loudspeaker and the noise signal picked up by the microphone at the center of the feedback microphone array. The method of calculating the acoustic transfer function according to the average test signal may refer to the existing calculation method of the acoustic transfer function, and will not be repeated here.

Step A40, setting filter coefficients in the active noise reduction circuit according to the acoustic transfer function;

After calculating the acoustic transfer function from the loudspeaker to the center of the feedback microphone array, the filter coefficients in the active noise reduction circuit can be set according to the acoustic transfer function. Specifically, the method for setting filter coefficients according to the acoustic transfer function can generally refer to the existing method for setting filter coefficients, which will not be repeated here.

It should be noted that, if the active noise reduction circuit is a feedback active noise reduction circuit, the filter coefficients of the feedback filter in the feedback active noise reduction circuit are set according to the acoustic transfer function from the loudspeaker to the center of the feedback microphone array. If the active noise reduction circuit is a hybrid active noise reduction circuit, then further, a section of test noise (hereinafter referred to as external test noise) can be preset in the external test equipment, and the external test noise is played through the external test equipment, and through the feedforward Microphone and feedback microphone detect this external test noise signal, calculate the acoustic transfer function (hereinafter referred to as the first function) of external sound source to feedforward microphone according to the external test noise signal detected by feedforward microphone; The test noise signal is averaged to obtain the average external test signal. According to the external test noise signal detected by the feedforward microphone and the average test signal, the acoustic transfer function (hereinafter referred to as the second function); according to the first function, the second function and the third function (acoustic transfer function from the loudspeaker to the center of the feedback microphone array), the filter coefficients of the feedforward filter in the feedforward active noise reduction circuit and the feedback active noise reduction circuit are jointly set. Filter coefficients for the feedback filter in the noise reduction circuit.

The step S202 includes:

Step S2021, input the average signal into the active noise reduction circuit, perform noise reduction processing based on the filter coefficients, and obtain a denoising signal corresponding to the average signal.

After setting the filter coefficient in the active noise reduction circuit of the earphone device, when the active noise reduction function is turned on during use, after calculating the average signal of each first noise signal, the average signal can be input into the active noise reduction circuit, Noise reduction processing is performed based on the set filter coefficients in the active noise reduction circuit to obtain a noise reduction signal corresponding to the average signal. It should be noted that the specific process of denoising the signal based on the filter in the active noise reduction circuit to obtain the denoising signal can refer to the existing active noise reduction circuit, and will not be repeated here.

Further, based on the first embodiment above, a third embodiment of the noise reduction method of the present application is proposed. In this embodiment, the step S20 includes:

Step S203, input each of the first noise signals into the corresponding active noise reduction branch for noise reduction processing, and obtain the branch noise reduction signals corresponding to each of the first noise signals;

Step S204, averaging each of the denoising signals of the branches, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.

In this embodiment, for the first noise signal detected by each feedback microphone, noise reduction processing may be performed first, and then the noise reduction signal may be averaged.

Specifically, the active noise reduction circuit may include active noise reduction branches corresponding to the respective feedback microphones, that is, one feedback microphone corresponds to one active noise reduction branch. For the first noise signals detected by each feedback microphone, the earphone device may first input each first noise signal into the corresponding active noise reduction branch for noise reduction processing, and obtain branch noise cancellation signals corresponding to each first noise signal. . That is, a first noise signal detected by a feedback microphone is input into an active noise reduction branch corresponding to the feedback microphone for noise reduction processing, and a branch noise cancellation signal corresponding to the first noise signal is obtained.

The denoising signals of each branch are averaged, and the averaged signal is used as the denoising signal corresponding to the average signal of each first noise signal, that is, although it is not directly denoising the average signal of each first noise signal to obtain For the denoising signal, however, the signal obtained by performing noise reduction processing on each first noise signal using the corresponding active noise reduction branch and then averaging can be regarded as the denoising signal corresponding to the average signal of each first noise signal.

The active noise reduction branch can be a feedback active noise reduction circuit or a hybrid active noise reduction circuit.

When the active noise reduction branch is a feedback active noise reduction circuit, the earphone device inputs each first noise signal to the corresponding feedback active noise reduction circuit for noise reduction processing, and obtains feedback noise reduction signals corresponding to each first noise signal (That is, the branch denoising signal), the signal obtained by averaging the denoising signals of each branch is directly used as the denoising signal corresponding to the average signal of each first noise signal, and the denoising signal is played through the loudspeaker. The filter coefficients of the feedback filter in each feedback active noise reduction circuit can be designed by testing in advance, and the design method can refer to the existing feedback filter design method, wherein the output signal of the feedback microphone (the detected noise signal), use the output signal of the corresponding feedback microphone to participate in the corresponding filter design.

When the active noise reduction branch is a hybrid active noise reduction circuit, each active noise reduction branch can use different feedback active noise reduction circuits, but share a feedforward active noise reduction circuit; For the second noise signal, input the second noise signal into the feedforward active noise reduction circuit for noise reduction processing to obtain a feedforward noise reduction signal; input the first noise signals detected by each feedback microphone into the corresponding feedback active noise reduction The circuit performs noise reduction processing to obtain each feedback denoising signal; the feedforward denoising signal is added to each feedback denoising signal and then averaged, or each feedback denoising signal is averaged and then combined with the feedforward denoising signal Adding, the calculated result is used as the denoising signal corresponding to the average signal of each first noise signal, that is, the calculated result is played through the speaker. Similarly, the filter coefficients of the feedforward filter in the feedforward active noise reduction circuit and the feedback filter in the feedback active noise reduction circuit can be designed through pre-testing, and the design method can refer to the existing feedforward filter And the design method of the feedback filter, wherein when the output signal (detected noise signal) of the feedback microphone is needed, the output signal of the corresponding feedback microphone is used to participate in the corresponding filter design.

Further, in one embodiment, before the step S10, it also includes:

Step B10, acquiring test noise signals detected by each of the feedback microphones respectively, wherein the test noise signal is a signal detected by each of the feedback microphones after playing preset test noise through the speaker;

Step B20, calculating an acoustic transfer function from the loudspeaker to the corresponding feedback microphone according to each of the test noise signals;

Step B30, respectively setting the branch filter coefficients in the corresponding active noise reduction branch according to each of the acoustic transfer functions;

The acoustic transfer function from the loudspeaker to the corresponding feedback microphone is calculated according to each test noise signal respectively. That is, for each feedback microphone, the acoustic transfer function from the loudspeaker to the feedback microphone is calculated using the test noise signal detected by the feedback microphone. Then, a feedback microphone corresponds to an acoustic transfer function. Set the branch filter coefficients in the corresponding active noise reduction branch according to each acoustic transfer function, that is, for each feedback microphone, use the acoustic transfer function corresponding to the feedback microphone to set the corresponding active noise reduction of the feedback microphone. Branch filter coefficients in noisy branches.

It should be noted that if the active noise reduction branch is a feedback active noise reduction circuit, the filter coefficients of the feedback filters in each feedback active noise reduction circuit are correspondingly set according to the acoustic transfer function from the speaker to each feedback microphone . If the active noise reduction circuit is a hybrid active noise reduction circuit, then further, a section of test noise (hereinafter referred to as external test noise) can be preset in the external test equipment, and the external test noise is played through the external test equipment, and through the feedforward Microphone and feedback microphone detect this external test noise signal, calculate the acoustic transfer function (hereinafter referred to as the first function) of external sound source to feedforward microphone according to the external test noise signal detected by feedforward microphone; The external test noise signal and the external test noise signal detected by each feedback microphone are respectively calculated to obtain the acoustic transfer function (hereinafter referred to as the second function) from the feedforward microphone to each feedback microphone; according to the first function, each second function and each The third function (speaker-to-feedback microphone acoustic transfer function) jointly sets the filter coefficients of the feedforward filter in the feedforward ANC circuit and the filter coefficients of the feedback filter in each feedback ANC circuit.

The step S204 includes:

Step S2041, input each of the first noise signals into the corresponding active noise reduction branch, perform noise reduction processing based on the corresponding branch filter coefficients, and obtain branch noise reduction signals corresponding to each of the first noise signals .

After setting the branch filter coefficients in the active noise reduction branch of the earphone device, when the active noise reduction function is turned on during use, each first noise signal can be respectively input into the corresponding active noise reduction branch. The filter coefficients set in the denoising branches are subjected to denoising processing to obtain branch denoising signals respectively corresponding to the first noise signals. It should be noted that the specific process of denoising the signal based on the filter in the ANR branch to obtain the denoising signal can refer to the existing ANR circuit, and will not be repeated here.

Further, in one embodiment, when the distribution position of the feedback microphone array meets the position condition after error compensation, the step S20 includes:

Step S205, obtaining weights corresponding to each of the feedback microphones, wherein the weights are set in advance according to the error of the distribution position of the feedback microphone array relative to the position condition;

When there is an error between the distribution position of the feedback microphone array and the position condition, the error can be compensated. In this embodiment, the error compensation method can be set in advance according to the error of the distribution position of the feedback microphone array relative to the position condition. The weight corresponding to the feedback microphone array. Specifically, the weight may be set by means of testing, so that the noise signal obtained by weighting and averaging the noise signals detected by each feedback microphone according to the set weight is consistent with the noise signal at the center of the feedback microphone array.

Step S206, weighting and averaging each of the denoising signals of the branches according to corresponding weights, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.

After the first noise signal is detected by each feedback microphone, the noise cancellation signal of each branch may be weighted and averaged according to the corresponding weight. Among them, it can be understood that there is a one-to-one correspondence between the feedback microphone, the first noise signal, the active noise reduction branch, the weight, and the branch noise cancellation signal, and the weighted average is to compare the noise cancellation signal of each branch with the corresponding weight Multiply and then average. The weighted average result is used as the denoising signal corresponding to the average signal of each first noise signal.

Further, in one embodiment, when the first noise signals are averaged and then the noise reduction process is performed, the first noise signals can also be weighted and averaged according to the corresponding weights to obtain the average signal, and then the average signal is input The active noise reduction circuit performs noise reduction processing to obtain a denoising signal corresponding to the average signal of each first noise signal.

In addition, an embodiment of the present application also proposes a noise reduction device, the noise reduction device is deployed in a headphone device, and the headphone device includes an active noise reduction circuit, a speaker, a sound hole, and a feedback microphone array, and the feedback microphone array includes A plurality of feedback microphones, the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is that the distribution plane of the feedback microphone array is perpendicular to the speaker and the outlet The connection between the sound holes, and the center of the feedback microphone array is on the connection, with reference to Fig. 5, the noise reduction device includes:

An acquisition module 10, configured to acquire first noise signals respectively detected by each of the feedback microphones;

A noise reduction module 20, configured to perform noise reduction processing on each of the first noise signals through the active noise reduction circuit, to obtain a noise reduction signal corresponding to an average signal of each of the first noise signals;

The playback module 30 is configured to play the noise-canceling signal through the loudspeaker.

Further, the noise reduction module 20 includes:

a first averaging unit, configured to average each of the first noise signals to obtain an average signal;

The first noise reduction unit is configured to input the average signal into the active noise reduction circuit for noise reduction processing to obtain a noise reduction signal corresponding to the average signal.

Further, the acquiring module 10 is also used to acquire the test noise signals detected by each of the feedback microphones respectively, wherein the test noise signals are detected by each of the feedback microphones after the preset test noise is played through the speakers to the signal;

The device also includes:

An averaging module, configured to average each of the test noise signals to obtain an average test signal;

A first calculation module, configured to calculate an acoustic transfer function from the loudspeaker to the center of the feedback microphone array according to the average test signal;

A first setting module, configured to set filter coefficients in the active noise reduction circuit according to the acoustic transfer function;

The first noise reduction unit is also used for:

Further, the active noise reduction circuit includes active noise reduction branches respectively corresponding to the feedback microphones, and the noise reduction module 20 includes:

The second noise reduction unit is configured to input each of the first noise signals into the corresponding active noise reduction branch for noise reduction processing, and obtain branch noise reduction signals corresponding to each of the first noise signals;

The second averaging unit is configured to average each of the branch denoising signals, and use the result as a denoising signal corresponding to the average signal of each of the first noise signals.

The device also includes:

The second calculation module is used to calculate and obtain the acoustic transfer function from the loudspeaker to the corresponding feedback microphone according to each of the test noise signals;

The second setting module is used to set the branch filter coefficients in the corresponding active noise reduction branch according to the acoustic transfer functions respectively;

The second averaging unit is also used for:

Further, when the distribution position of the feedback microphone array meets the position condition after error compensation, the second averaging unit is also used for:

Further, the active noise reduction circuit includes a feedforward active noise reduction circuit and a feedback active noise reduction circuit, the earphone device also includes a feedforward microphone, and the noise reduction module 20 includes:

an acquisition unit, configured to acquire a second noise signal detected by the feedforward microphone;

A third noise reduction unit, configured to perform noise reduction processing on the second noise signal through the feedforward active noise reduction circuit to obtain a feedforward noise reduction signal;

The fourth noise reduction unit is configured to perform noise reduction processing on each of the first noise signals through the feedback active noise reduction circuit to obtain a feedback noise reduction signal corresponding to an average signal of each of the first noise signals;

A calculation unit, configured to add the feedforward denoising signal and the feedback denoising signal, and use the result as a denoising signal corresponding to the average signal of each of the first noise signals.

The expanded content of the specific implementation of the noise reduction device of the present application is basically the same as that of the embodiments of the above noise reduction method, and will not be repeated here.

The earphone device of the present application may include an active noise reduction circuit, a loudspeaker, a sound outlet, and a feedback microphone array, the feedback microphone array includes a plurality of feedback microphones, and the distribution position of the feedback microphone array meets a position condition or meets a condition after error compensation. The position condition, the position condition is that the distribution plane of the feedback microphone array is perpendicular to the line between the speaker and the sound outlet, and the center of the feedback microphone array is on the line, The earphone device further includes a memory, a processor, and a noise reduction program stored on the memory and operable on the processor, when the noise reduction program is executed by the processor, operations such as:

The noise-canceling signal is played through the loudspeaker.

Further, performing noise reduction processing on each of the first noise signals through the active noise reduction circuit to obtain a denoising signal corresponding to an average signal of each of the first noise signals includes:

averaging each of the first noise signals to obtain an average signal;

Further, before the acquisition of the first noise signals respectively detected by each of the feedback microphones, it also includes:

averaging each of the test noise signals to obtain an average test signal;

The inputting the average signal into the active noise reduction circuit for noise reduction processing, and obtaining the denoising signal corresponding to the average signal includes:

Further, the active noise reduction circuit includes an active noise reduction branch corresponding to each of the feedback microphones, and the active noise reduction circuit performs noise reduction processing on each of the first noise signals to obtain The denoising signal corresponding to the average signal of the first noise signal includes:

The step of inputting each of the first noise signals into the corresponding active noise reduction branch for noise reduction processing, and obtaining branch noise reduction signals corresponding to each of the first noise signals includes:

Further, when the distribution position of the feedback microphone array meets the position condition after error compensation, the noise cancellation signals of each of the branches are averaged, and the result is taken as the average of the first noise signals The denoising signal corresponding to the signal includes:

Further, the active noise reduction circuit includes a feed-forward active noise reduction circuit and a feedback active noise reduction circuit, and the earphone device also includes a feed-forward microphone, and each of the first The noise signal is subjected to noise reduction processing, and the denoising signal corresponding to the average signal of each of the first noise signals obtained includes:

acquiring a second noise signal detected by the feedforward microphone;

In addition, the embodiment of the present application also proposes a computer-readable storage medium, on which a noise reduction program is stored, and when the noise reduction program is executed by a processor, the steps of the above-mentioned noise reduction method are implemented.

For the various embodiments of the earphone device and the computer-readable storage medium of the present application, reference may be made to the various embodiments of the noise reduction method of the present application, which will not be repeated here.

It should be noted that, in this document, the term "comprising", "comprising" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article or apparatus comprising a set of elements includes not only those elements, It also includes other elements not expressly listed, or elements inherent in the process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus comprising that element.

The serial numbers of the above embodiments of the present application are for description only, and do not represent the advantages and disadvantages of the embodiments.

Through the description of the above embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus a necessary general-purpose hardware platform, and of course also by hardware, but in many cases the former is better implementation. Based on such an understanding, the technical solution of the present application can be embodied in the form of a software product in essence or the part that contributes to the prior art, and the computer software product is stored in a storage medium (such as ROM/RAM, disk, CD) contains several instructions to make a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) execute the methods described in the various embodiments of the present application.

The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structures or equivalent process transformations made by using the description of the application and the accompanying drawings are directly or indirectly used in other related technical fields. , are all included in the patent protection scope of the present application in the same way.

Claims

A noise reduction method, characterized in that the noise reduction method is applied to an earphone device, and the earphone device includes an active noise reduction circuit, a loudspeaker, a sound outlet and a feedback microphone array, and the feedback microphone array includes a plurality of feedback microphones , the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is that the distribution plane of the feedback microphone array is perpendicular to between the speaker and the sound outlet The connection line, and the center of the feedback microphone array is on the connection line, the noise reduction method includes the following steps:

acquiring first noise signals respectively detected by each of the feedback microphones;

performing noise reduction processing on each of the first noise signals through the active noise reduction circuit to obtain a noise reduction signal corresponding to an average signal of each of the first noise signals;

The noise-canceling signal is played through the loudspeaker.
The noise reduction method according to claim 1, wherein the active noise reduction circuit performs noise reduction processing on each of the first noise signals to obtain an average signal corresponding to each of the first noise signals. The steps for denoising the signal include:

averaging each of the first noise signals to obtain an average signal;

Inputting the average signal into the active noise reduction circuit for noise reduction processing to obtain a denoising signal corresponding to the average signal.
The noise reduction method according to claim 2, wherein before the step of acquiring the first noise signals respectively detected by each of the feedback microphones, further comprising:

Acquiring test noise signals detected by each of the feedback microphones, wherein the test noise signal is a signal detected by each of the feedback microphones after playing preset test noise through the speaker;

averaging each of the test noise signals to obtain an average test signal;

calculating an acoustic transfer function from the loudspeaker to the center of the feedback microphone array according to the average test signal;

setting filter coefficients in the active noise reduction circuit according to the acoustic transfer function;

The step of inputting the average signal into the active noise reduction circuit to perform noise reduction processing, and obtaining a denoising signal corresponding to the average signal includes:

Inputting the average signal into the active noise reduction circuit, performing noise reduction processing based on the filter coefficients, to obtain a denoising signal corresponding to the average signal.
The noise reduction method according to claim 1, wherein the active noise reduction circuit includes an active noise reduction branch corresponding to each of the feedback microphones, and the active noise reduction circuit is used for each of the The first noise signal is subjected to noise reduction processing, and the step of obtaining the denoising signal corresponding to the average signal of each of the first noise signals includes:

Input each of the first noise signals into the corresponding active noise reduction branch to perform noise reduction processing, and obtain branch noise reduction signals corresponding to each of the first noise signals;

The denoising signals of each of the branches are averaged, and the result is used as a denoising signal corresponding to the average signal of each of the first noise signals.
The noise reduction method according to claim 4, wherein before the step of acquiring the first noise signals respectively detected by each of the feedback microphones, further comprising:

Acquiring test noise signals detected by each of the feedback microphones, wherein the test noise signal is a signal detected by each of the feedback microphones after playing preset test noise through the speaker;

calculating an acoustic transfer function from the loudspeaker to the corresponding feedback microphone according to each of the test noise signals;

Setting the branch filter coefficients in the corresponding active noise reduction branch according to each of the acoustic transfer functions;

The step of inputting each of the first noise signals into the corresponding active noise reduction branch for noise reduction processing, and obtaining the branch denoising signals corresponding to each of the first noise signals includes:

Each of the first noise signals is input to a corresponding active noise reduction branch, and noise reduction processing is performed based on the corresponding branch filter coefficients to obtain branch denoising signals corresponding to each of the first noise signals.
The noise reduction method according to claim 4, wherein when the distribution position of the feedback microphone array meets the position condition after error compensation, the noise reduction signals of each of the branches are averaged, The step of using the result as the denoising signal corresponding to the average signal of each of the first noise signals includes:

Acquiring weights corresponding to each of the feedback microphones, wherein the weights are set in advance according to the error of the distribution position of the feedback microphone array relative to the position condition;

Performing a weighted average on each of the branch denoising signals according to the corresponding weight, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.
The noise reduction method according to any one of claims 1 to 6, wherein the active noise reduction circuit includes a feedforward active noise reduction circuit and a feedback active noise reduction circuit, and the earphone device also includes a feedforward active noise reduction circuit. Microphone, the step of performing noise reduction processing on each of the first noise signals through the active noise reduction circuit, and obtaining a denoising signal corresponding to an average signal of each of the first noise signals includes:

acquiring a second noise signal detected by the feedforward microphone;

performing noise reduction processing on the second noise signal through the feedforward active noise reduction circuit to obtain a feedforward noise reduction signal;

performing noise reduction processing on each of the first noise signals through the feedback active noise reduction circuit to obtain a feedback denoising signal corresponding to an average signal of each of the first noise signals;

adding the feedforward denoising signal and the feedback denoising signal, and using the result as a denoising signal corresponding to the average signal of each of the first noise signals.
A noise reduction device, characterized in that the noise reduction device is deployed on a headphone device, and the headphone device includes an active noise reduction circuit, a speaker, a sound outlet, and a feedback microphone array, and the feedback microphone array includes a plurality of feedback microphones , the distribution position of the feedback microphone array meets a position condition or meets the position condition after error compensation, and the position condition is that the distribution plane of the feedback microphone array is perpendicular to between the speaker and the sound outlet The connection line, and the center of the feedback microphone array is on the connection line, the noise reduction device includes:

An acquisition module, configured to acquire the first noise signals respectively detected by each of the feedback microphones;

A noise reduction module, configured to perform noise reduction processing on each of the first noise signals through the active noise reduction circuit, to obtain a noise reduction signal corresponding to an average signal of each of the first noise signals;

A playback module, configured to play the noise-canceling signal through the loudspeaker.
An earphone device, characterized in that the earphone device includes an active noise reduction circuit, a speaker, a sound outlet, and a feedback microphone array, the feedback microphone array includes a plurality of feedback microphones, and the distribution positions of the feedback microphone array conform to a The position condition or meet the position condition after error compensation, the position condition is that the distribution plane of the feedback microphone array is perpendicular to the line between the speaker and the sound outlet, and the feedback microphone array Centering on the connection, the earphone device further includes a memory, a processor, and a noise reduction program stored on the memory and operable on the processor, and the noise reduction program is executed by the processor When realizing the steps of the noise reduction method as described in any one of claims 1 to 7.
A computer-readable storage medium, characterized in that a noise reduction program is stored on the computer-readable storage medium, and when the noise reduction program is executed by a processor, the method according to any one of claims 1 to 7 is realized. The steps of the noise reduction method.