Microphone array noise reduction methods, devices, systems, electronic devices and storage media

Abstract

This disclosure provides a microphone array noise reduction method, apparatus, system, electronic device, and storage medium. The method includes: acquiring an audio signal to be denoised; performing frequency domain processing on the audio signal to obtain a frequency domain signal; responding to a first sub-frequency domain signal with a frequency less than a preset threshold in the frequency domain signal, performing a first noise reduction process based on a pre-set subtractive microphone array to obtain a denoised first sub-frequency domain signal; responding to a second sub-frequency domain signal with a frequency greater than or equal to a preset threshold in the frequency domain signal, performing a second noise reduction process based on a pre-set additive microphone array to obtain a denoised second sub-frequency domain signal; and obtaining a denoised audio signal based on the denoised first and second sub-frequency domain signals. This disclosure combines the superior characteristics of subtractive and additive microphone arrays to perform targeted noise reduction processing on low-frequency and high-frequency signals respectively, resulting in better noise reduction performance.

Description

Technical Field

[0001] This disclosure relates to the field of signal processing technology, and more specifically, to a microphone array noise reduction method, apparatus, system, electronic device, and storage medium. Background Technology

[0002] With the development of modern technology, people are using headphones more and more widely. In order to ensure the call quality when users wear headphones, multiple microphones are often set up in the headphones to form a microphone array. The microphone array uses beamforming to reduce noise in the collected sound signal.

[0003] The relevant technologies mainly involve two types of noise reduction methods for microphone arrays. The typical representative of additive microphone arrays is the generalized sidelobe canceller (GSC), and the typical representative of subtractive microphone arrays is the differential microphone array (DMA).

[0004] However, as portable mobile devices, especially True Wireless Stereo (TWS) headphones, headphones are significantly miniaturized, and their microphone spacing is small. Therefore, the two noise reduction methods mentioned above cannot achieve good noise reduction effects when used alone. Summary of the Invention

[0005] This disclosure provides at least one microphone array noise reduction method, apparatus, system, electronic device, and storage medium to improve the noise reduction performance of microphone arrays.

[0006] In a first aspect, embodiments of this disclosure provide a microphone array noise reduction method, including:

[0007] Acquire the audio signal to be noise-reduced;

[0008] The sound signal is processed in the frequency domain to obtain a frequency domain signal;

[0009] In response to a first sub-frequency domain signal whose frequency is less than a preset threshold in the frequency domain signal, the first sub-frequency domain signal is subjected to a first noise reduction process based on a pre-set attenuated microphone array to obtain a noise-reduced first sub-frequency domain signal.

[0010] In response to a second sub-frequency domain signal whose frequency is greater than or equal to a preset threshold in the frequency domain signal, a second noise reduction process is performed on the second sub-frequency domain signal based on a preset additive microphone array to obtain a noise-reduced second sub-frequency domain signal.

[0011] Based on the first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction, the noise-reduced sound signal is obtained.

[0012] In one possible implementation, the subtractive microphone array is a differential microphone array (DMA), and the additive microphone array is a generalized sidelobe canceller (GSC).

[0013] In one possible implementation, the first noise reduction processing of the first sub-frequency domain signal based on a pre-set attenuating microphone array to obtain the noise-reduced first sub-frequency domain signal includes:

[0014] For the first frequency point where the first sub-frequency domain signal is located, the first sub-frequency domain signal is filtered based on a pre-set low-pass filter to obtain the filtered first sub-frequency domain signal.

[0015] The filtered first sub-frequency domain signal is subjected to a first noise reduction process based on a pre-set DMA to obtain the noise-reduced first sub-frequency domain signal.

[0016] In one possible implementation, the passband bandwidth of the low-pass filter is positively correlated with the frequency of the first sub-frequency domain signal.

[0017] In one possible implementation, obtaining the denoised audio signal based on the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal includes:

[0018] Align the first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction to obtain the aligned first sub-frequency domain signal and second sub-frequency domain signal.

[0019] Based on the aligned first sub-frequency domain signal and second sub-frequency domain signal, the noise-reduced audio signal is obtained.

[0020] In one possible implementation, aligning the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal includes:

[0021] The second sub-frequency domain signal after noise reduction is delayed based on the number of taps of the low-pass filter to determine the delayed second sub-frequency domain signal.

[0022] Based on the denoised first sub-frequency domain signal and the delayed second sub-frequency domain signal, the aligned first sub-frequency domain signal and second sub-frequency domain signal are obtained.

[0023] In one possible implementation, obtaining the denoised audio signal based on the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal includes:

[0024] The first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction are summed to obtain the noise-reduced frequency domain signal.

[0025] The denoised frequency domain signal is processed in the time domain to obtain the denoised audio signal.

[0026] In one possible implementation, acquiring the audio signal to be denoised includes:

[0027] In response to the headphone communication command of the true wireless stereo (TWS) earphones, the sound signal to be noise-reduced is acquired.

[0028] Secondly, this disclosure also provides a microphone array noise reduction device, comprising:

[0029] The acquisition module is used to acquire the audio signal to be denoised;

[0030] The frequency domain processing module is used to perform frequency domain processing on the sound signal to obtain a frequency domain signal;

[0031] The first noise reduction module is used to respond to a first sub-frequency domain signal with a frequency less than a preset threshold in the frequency domain signal, and to perform a first noise reduction process on the first sub-frequency domain signal based on a preset attenuating microphone array to obtain the noise-reduced first sub-frequency domain signal.

[0032] The second noise reduction module is used to respond to a second sub-frequency domain signal in the frequency domain signal whose frequency is greater than or equal to a preset threshold, and to perform a second noise reduction process on the second sub-frequency domain signal based on a preset additive microphone array to obtain a noise-reduced second sub-frequency domain signal.

[0033] The determining module is used to obtain the denoised sound signal based on the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal.

[0034] Thirdly, this disclosure also provides a microphone array noise reduction system, including: an attenuating microphone array, an additive microphone array, and a processor; the processor is connected to the attenuating microphone array and the additive microphone array respectively;

[0035] The processor is configured to acquire the audio signal to be denoised; perform frequency domain processing on the audio signal to obtain a frequency domain signal; the frequency domain signal includes a first sub-frequency domain signal with a frequency less than a preset threshold and a second sub-frequency domain signal with a frequency greater than or equal to the preset threshold; and obtain a denoised audio signal based on the first sub-frequency domain signal after denoising by the subtractive microphone array and the second sub-frequency domain signal after denoising by the additive microphone array.

[0036] The subtractive microphone array is used to perform a first noise reduction process on the first sub-frequency domain signal to obtain a noise-reduced first sub-frequency domain signal.

[0037] The additive microphone array is used to perform a second noise reduction process on the second sub-frequency domain signal to obtain a noise-reduced second sub-frequency domain signal.

[0038] Fourthly, this disclosure also provides an electronic device, including: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory via the bus, and when the machine-readable instructions are executed by the processor, the microphone array noise reduction method as described in any one of the first aspects and various embodiments thereof is performed.

[0039] Fifthly, this disclosure also provides a computer-readable storage medium storing a computer program that, when executed by a processor, performs the microphone array noise reduction method as described in any one of the first aspects and its various embodiments.

[0040] By employing the aforementioned microphone array noise reduction method, apparatus, system, electronic device, and storage medium, upon acquiring the audio signal to be denoised, frequency domain processing can be performed first. Then, for the first sub-frequency domain signal with lower frequencies after frequency domain processing, a first noise reduction process can be performed based on a subtractive microphone array to obtain a denoised first sub-frequency domain signal. For the second sub-frequency domain signal with higher frequencies after frequency domain processing, a second noise reduction process can be performed based on an additive microphone array to obtain a denoised second sub-frequency domain signal. Finally, based on the denoised first and second sub-frequency domain signals, the denoised audio signal can be obtained. This disclosure combines the superior characteristics of subtractive and additive microphone arrays to perform targeted noise reduction processing on low-frequency and high-frequency signals respectively. The resulting denoised audio signal can eliminate noise in the audio signal to a greater extent, resulting in better noise reduction performance.

[0041] Other advantages of this disclosure will be explained in more detail below with reference to the accompanying drawings.

[0042] It should be understood that the above description is merely an overview of the technical solution of this disclosure, so as to enable a clearer understanding of the technical means of this disclosure, and thus enable its implementation in accordance with the contents of the specification. To make the above and other objects, features, and advantages of this disclosure more apparent and understandable, specific embodiments of this disclosure are illustrated below. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be briefly described below. These drawings are incorporated in and constitute a part of this specification. They illustrate embodiments conforming to this disclosure and, together with the specification, serve to explain the technical solutions of this disclosure. It should be understood that the following drawings only show some embodiments of this disclosure and should not be considered as limiting the scope. Those skilled in the art can obtain other related drawings based on these drawings without creative effort. Furthermore, the same reference numerals denote the same components throughout the drawings. In the drawings:

[0044] Figure 1 A flowchart of a microphone array noise reduction method provided in an embodiment of this disclosure is shown;

[0045] Figure 2 The flowchart of the specific method of GSC noise reduction in the microphone array noise reduction method provided in the embodiments of this disclosure is shown;

[0046] Figure 3 A schematic diagram of a microphone array noise reduction system provided in an embodiment of this disclosure is shown;

[0047] Figure 4 A schematic diagram of a microphone array noise reduction device provided in an embodiment of this disclosure is shown;

[0048] Figure 5 A schematic diagram of an electronic device provided in an embodiment of the present disclosure is shown. Detailed Implementation

[0049] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0050] In the description of embodiments disclosed herein, it should be understood that terms such as “comprising” or “having” are intended to indicate the presence of features, numbers, steps, behaviors, components, portions or combinations thereof disclosed herein, and are not intended to exclude the possibility of the presence of one or more other features, numbers, steps, behaviors, components, portions or combinations thereof.

[0051] Unless otherwise stated, " / " means "or". For example, A / B can mean A or B. In this article, "and / or" is merely a way of describing the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone.

[0052] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0053] Research has shown that noise reduction using additive microphone arrays is widely used. However, the calculations for additive microphone arrays like GSCs are complex, and due to the inherent characteristics of additive microphones, their performance is best when the microphone size is close to half the wavelength. Limited by these characteristics, directly applying GSCs to headphones, especially in TWS earbuds with advantages such as small size and portability, cannot adequately meet noise reduction requirements.

[0054] In order to at least partially address one or more of the above-mentioned problems and other potential problems, this disclosure provides at least one scheme for joint noise reduction by combining multiple microphone arrays to improve noise reduction performance.

[0055] To facilitate understanding of this embodiment, a detailed description of the microphone array noise reduction method disclosed in this disclosure is provided first. The execution entity of the microphone array noise reduction method provided in this disclosure is generally an electronic device with a certain computing power. This electronic device may include, for example, a terminal device or other processing device. The terminal device may be a user equipment (UE), a mobile device, a user terminal, an in-vehicle device, a wearable device, etc. In practical applications, the user equipment may be something such as TWS earphones. Furthermore, in some possible implementations, this microphone array noise reduction method can be implemented by a processor calling computer-readable instructions stored in memory.

[0056] See Figure 1 The diagram shows a flowchart of a microphone array noise reduction method provided in an embodiment of this disclosure. The method includes steps S101 to S105, wherein:

[0057] S101: Acquire the audio signal to be noise-reduced;

[0058] S102: Perform frequency domain processing on the sound signal to obtain a frequency domain signal;

[0059] S103: In response to a first sub-frequency domain signal with a frequency less than a preset threshold in the frequency domain signal, perform a first noise reduction process on the first sub-frequency domain signal based on a preset attenuating microphone array to obtain a noise-reduced first sub-frequency domain signal.

[0060] S104: In response to a second sub-frequency domain signal with a frequency greater than or equal to a preset threshold in the frequency domain signal, perform a second noise reduction process on the second sub-frequency domain signal based on a preset additive microphone array to obtain a noise-reduced second sub-frequency domain signal.

[0061] S105: Based on the first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction, the noise-reduced sound signal is obtained.

[0062] To facilitate understanding of the microphone array noise reduction method provided in this disclosure, the application scenarios of the method will be described in detail below. The microphone array noise reduction method in this disclosure can be applied to any scenario suitable for microphone array noise reduction, such as traffic noise scenarios, abnormal sound detection scenarios, etc. In addition, it can also be adapted to business products that require noise reduction, such as TWS earphones. Considering the widespread use of TWS earphones, the following examples will mainly focus on TWS earphones as the implementing entity.

[0063] The audio signal to be denoised here can be an audio signal obtained in the various application scenarios exemplified above, or it can be a user's audio signal obtained in response to the headphone communication command of a TWS earphone. Considering the complexity of the user's environment, the audio signal may be accompanied by noise from various sources. Based on this, the microphone array noise reduction method provided in this disclosure can first perform frequency domain processing on the audio signal to obtain a frequency domain signal. This is mainly because, during frequency domain analysis, the change in the signal spectrum after the signal passes through the system can be intuitively reflected, thereby facilitating the analysis of system performance. The obtained frequency domain signal can refer to a signal whose independent variable is frequency, that is, the horizontal axis is frequency, and the vertical axis is the amplitude of the frequency signal.

[0064] Considering the performance differences of different microphone arrays at different frequencies, different frequencies can be distinguished here. At lower frequencies, subtractive microphone arrays can be used for noise reduction, while at higher frequencies, additive microphone arrays can be used for noise reduction. Finally, the denoised sound signal is obtained by fusing the denoised signals and converting the frequency domain to the time domain.

[0065] The frequency domain signal in this embodiment includes a first sub-frequency domain signal with a frequency less than a preset threshold. A first noise reduction process is performed on the first sub-frequency domain signal using a subtractive microphone array to maximize the noise reduction performance in a scenario where the microphone spacing d is relative to the wavelength of the signal in a small-sized microphone array. In addition, the frequency domain signal also includes a second sub-frequency domain signal with a frequency greater than or equal to a preset threshold. A second noise reduction process is performed on the second sub-frequency domain signal using an additive microphone array to adaptively adjust according to the direction of the signal, ensuring noise reduction performance in a scenario where the microphone size is close to half the wavelength.

[0066] The preset threshold for the frequency domain can be 1.5Hz. For example, a second noise reduction process is performed on a second sub-frequency domain signal that is higher than 1.5Hz but lower than the maximum frequency value. Or, a first noise reduction process is performed on a first sub-frequency domain signal that is higher than the minimum frequency value but lower than 1.5Hz.

[0067] The subtractive microphone array here mainly refers to the differential microphone array (DMA), while the additive microphone array mainly refers to the generalized sidelobe canceller (GSC).

[0068] In practical applications, the results of the low-frequency part can be replaced by DMA coefficients instead of GSC operations. This can reduce the operational complexity in the low-frequency processing and further improve the noise reduction performance.

[0069] In this embodiment, the first sub-frequency domain signal after noise reduction obtained based on DMA processing and the second sub-frequency domain signal after noise reduction obtained based on GSC processing can be summed to obtain the noise-reduced frequency domain signal. Then, the noise-reduced audio signal is obtained by performing time-domain processing on the noise-reduced frequency domain signal. Because more appropriate noise reduction processing is performed on both low-frequency and high-frequency results during the frequency domain processing, noise interference is eliminated to a greater extent in the final noise-reduced audio signal, ensuring the actual user experience of electronic devices such as TWS earphones.

[0070] In the actual process of denoising the low-frequency signal of the first sub-frequency domain signal using DMA, since DMA may amplify noise in the low-frequency part, a low-pass filter (LPF) can be added to average the low-frequency part across different frames and remove the influence of white noise. This can be achieved through the following steps:

[0071] Step 1: For the first frequency point where the first sub-frequency domain signal is located, filter the first sub-frequency domain signal based on the pre-set low-pass filter to obtain the filtered first sub-frequency domain signal.

[0072] Step 2: Perform the first noise reduction process on the filtered first sub-frequency domain signal based on the pre-set DMA to obtain the noise-reduced first sub-frequency domain signal.

[0073] Here, let Z be the signal at frequency w of the m-th antenna of the DMA in the t-th frame. m (t,e jw ), can make signal Z m (t,e jw After passing through a low-pass filter LPF(Z) m (t,e jw Filtering out the influence of white noise at this frequency. In the DMA-based noise reduction process, the ratio of the transmission equations for different antennas of the microphone array can be obtained first. Assuming the target direction is 0 degrees, H... H (e jw ,0)h(w)=1.

[0074] Then, the ratio of the transmission equations for different antennas with different microphone blocking directions θ is obtained, H H (e jw Since h(w) = 0 for an N-antenna array, N-1 blocking directions can be set. By solving the system of equations formed by the above two equations, the coefficients of the differential microphone array can be obtained, thus obtaining the first sub-frequency domain signal after noise reduction.

[0075] In practical TWS earphone applications, each earphone can have a microphone array consisting of two microphones, so the corresponding N=2.

[0076] Considering that white noise will be amplified at very low frequencies, resulting in instability, the passband bandwidth of the low-pass filter set here can be positively correlated with the frequency of the first sub-frequency domain signal. Thus, the lower the frequency, the narrower the passband bandwidth of the LPF, and vice versa. LPF = FIR(n), where n is the number of taps.

[0077] Considering that low-pass filters significantly introduce time delay, it's advisable to first align the low-frequency and high-frequency signals, and then combine the aligned sub-frequency domain signals to obtain the final noise reduction result. The alignment process can be performed as follows:

[0078] Step 1: Delay the noise-reduced second sub-frequency domain signal based on the number of taps of the low-pass filter to determine the delayed second sub-frequency domain signal;

[0079] Step 2: Based on the denoised first sub-frequency domain signal and the delayed second sub-frequency domain signal, obtain the aligned first sub-frequency domain signal and second sub-frequency domain signal.

[0080] Here, since the LPF differs at different frequencies, the delay can be set to n / 2 taps, and the results of higher frequencies can be delayed accordingly to align the signals. For example, for the low-frequency signal at the current second 0, the final noise reduction result can be obtained by combining it with the high-frequency signal delayed forward by 2 seconds.

[0081] To better understand the noise reduction process for high-frequency signals, we can then combine... Figure 2 Provide an example.

[0082] like Figure 2 As shown, the target signal is s(t), and the signal received by the m-th microphone is z. m (t), the noise signal received by the m-th microphone is n m (t), where the transfer function TF from the sound source to the m-th microphone is a. m (t), so z m (t)=a m (t)*s(t)+n m Z(t), m = 1, ..., M, is transformed to the frequency domain using a Short-Term Fourier Transform (STFT) to obtain Z. m (t,e jw ) = a m (t,e jw )*S(t,e jw )+N m (t,e jw ), m=1,...,M.

[0083] Using the main antenna as the reference antenna, calculate the ratio of the transmission equations of other antennas to that of this antenna, H. m (e jω ) = A m (e jω ) / A1(e jω ), H T (e jω )=[1 H1(e jω ...H m (e jω )).

[0084] The transmission equation can use a pre-set frequency sweep result.

[0085] For H T (e jω Normalize W0(e) jω )=H(e jω ) / ||H(e jω )|| 2 .

[0086] Such as algorithm flowchart Figure 2 The upper half shown

[0087] Construction noise,

[0088] Here, minimize E{||Y FBF (t,e jω )-G(t,e jω ) + U(e jω )|| 2 This function constructs G(t, e) for the target. j ω ).

[0089] In practice, an iterative method is needed to obtain G(t, e). jω ).

[0090]

[0091] P est (t,e jω )=ρP est (t-1, e) jω )+(1-ρ)v|Z m (t,e jω )| 2 .

[0092] In practical TWS earphone applications, each earphone can have a microphone array consisting of two microphones, thus corresponding to M=2.

[0093] It is known that, compared to DMA, which is a fixed coefficient and therefore simpler to calculate, GSC is more complex to calculate. However, GSC can be adaptively adjusted according to the direction of the signal, and due to the inherent characteristics of additive microphones, it performs best when the microphone size is close to half the wavelength, and its advantages in noise reduction processing of high-frequency signals are more prominent.

[0094] The microphone noise reduction method provided in this embodiment combines DMA and GSC, making full use of the advantages of both to achieve better noise reduction performance. Considering the instability of DMA at low frequencies, the method uses the same frequency point and inter-frame smoothing to reduce noise, thereby further improving the noise reduction performance and making it more practical.

[0095] Based on the microphone array noise reduction method provided in the above embodiments, this disclosure also provides a microphone array noise reduction system, such as... Figure 3As shown, the system mainly includes: a subtractive microphone array 301, an additive microphone array 302, and a processor 303; the processor 303 is connected to both the subtractive microphone array 301 and the additive microphone array 302.

[0096] Processor 303 is used to acquire the sound signal to be denoised; perform frequency domain processing on the sound signal to obtain a frequency domain signal; the frequency domain signal includes a first sub-frequency domain signal with a frequency less than a preset threshold and a second sub-frequency domain signal with a frequency greater than or equal to the preset threshold; and obtain a denoised sound signal based on the first sub-frequency domain signal after denoising by the subtractive microphone array 301 and the second sub-frequency domain signal after denoising by the additive microphone array 302.

[0097] The subtractive microphone array 301 is used to perform a first noise reduction process on the first sub-frequency domain signal to obtain the noise-reduced first sub-frequency domain signal.

[0098] An additive microphone array 302 is used to perform a second noise reduction process on the second sub-frequency domain signal to obtain a noise-reduced second sub-frequency domain signal.

[0099] Here, in conjunction with two microphone arrays (i.e., subtractive microphone array 301 and additive microphone array 302), the processor 303 performs targeted noise reduction processing on low-frequency and high-frequency signals respectively, resulting in better noise reduction performance.

[0100] For specific noise reduction schemes of the subtractive microphone array 301 and the additive microphone array 302, please refer to the description of the above embodiments, which will not be repeated here.

[0101] In the description of this specification, the references to terms such as "some possible implementations," "some implementations," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that implementation or example is included in at least one implementation or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same implementation or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more implementations or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different implementations or examples described in this specification, as well as the features of different implementations or examples.

[0102] Regarding the method flowcharts of embodiments of this disclosure, certain operations are described as different steps performed in a certain order. Such flowcharts are illustrative and not restrictive. Some steps described herein may be grouped together and performed in a single operation, some steps may be divided into multiple sub-steps, and some steps may be performed in an order different from that shown herein. The various steps shown in the flowcharts may be implemented in any way by any circuit structure and / or tangible mechanism (e.g., software running on a computer device, hardware (e.g., logic functions implemented by a processor or chip), and / or any combination thereof).

[0103] Those skilled in the art will understand that, in the above-described method of the specific implementation, the order in which each step is written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0104] Based on the same inventive concept, this disclosure also provides a microphone array noise reduction device corresponding to the microphone array noise reduction method. Since the principle of the device in this disclosure for solving the problem is similar to the microphone array noise reduction method described above in this disclosure, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0105] Reference Figure 4 The diagram shown is a schematic of a microphone array noise reduction device provided in an embodiment of this disclosure. The device includes: an acquisition module 401, a frequency domain processing module 402, a first noise reduction module 403, a second noise reduction module 404, and a determination module 405; wherein,

[0106] Acquisition module 401 is used to acquire the audio signal to be denoised;

[0107] The frequency domain processing module 402 is used to perform frequency domain processing on the sound signal to obtain a frequency domain signal;

[0108] The first noise reduction module 403 is used to respond to a first sub-frequency domain signal with a frequency less than a preset threshold in the frequency domain signal, and to perform a first noise reduction process on the first sub-frequency domain signal based on a preset attenuating microphone array to obtain the noise-reduced first sub-frequency domain signal.

[0109] The second noise reduction module 404 is used to respond to a second sub-frequency domain signal in the frequency domain signal whose frequency is greater than or equal to a preset threshold, and to perform a second noise reduction process on the second sub-frequency domain signal based on a preset additive microphone array to obtain a noise-reduced second sub-frequency domain signal.

[0110] The determination module 405 is used to obtain the denoised sound signal based on the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal.

[0111] In this embodiment, upon acquiring the audio signal to be denoised, frequency domain processing is first performed. Then, for the first sub-frequency domain signal with lower frequencies after frequency domain processing, a first denoising process is performed based on an attenuating microphone array to obtain a denoised first sub-frequency domain signal. For the second sub-frequency domain signal with higher frequencies after frequency domain processing, a second denoising process is performed based on an additive microphone array to obtain a denoised second sub-frequency domain signal. Finally, based on the denoised first and second sub-frequency domain signals, the denoised audio signal can be obtained. This disclosure combines the superior characteristics of attenuating and additive microphone arrays to perform targeted denoising processing on low-frequency and high-frequency signals respectively. The resulting denoised audio signal can eliminate noise in the audio signal to a greater extent, resulting in better denoising performance.

[0112] In one possible implementation, the subtractive microphone array is a differential microphone array (DMA), and the additive microphone array is a generalized sidelobe canceller (GSC).

[0113] In one possible implementation, the first noise reduction module 403 is configured to perform a first noise reduction process on the first sub-frequency domain signal based on a pre-set attenuating microphone array according to the following steps to obtain the noise-reduced first sub-frequency domain signal:

[0114] For the first frequency point where the first sub-frequency domain signal is located, the first sub-frequency domain signal is filtered based on a pre-set low-pass filter to obtain the filtered first sub-frequency domain signal.

[0115] The filtered first sub-frequency domain signal is subjected to first noise reduction processing based on the pre-set DMA to obtain the noise-reduced first sub-frequency domain signal.

[0116] In one possible implementation, the passband bandwidth of the low-pass filter is positively correlated with the frequency of the first sub-frequency domain signal.

[0117] In one possible implementation, the determining module 405 is configured to obtain the denoised audio signal based on the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal according to the following steps:

[0118] Align the first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction to obtain the aligned first sub-frequency domain signal and the second sub-frequency domain signal.

[0119] Based on the aligned first and second sub-frequency domain signals, the noise-reduced audio signal is obtained.

[0120] In one possible implementation, the determining module 405 is configured to align the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal according to the following steps:

[0121] The second sub-frequency domain signal after noise reduction is delayed based on the number of taps of the low-pass filter to determine the delayed second sub-frequency domain signal.

[0122] Based on the denoised first sub-frequency domain signal and the delayed second sub-frequency domain signal, the aligned first sub-frequency domain signal and second sub-frequency domain signal are obtained.

[0123] In one possible implementation, the determining module 405 is configured to obtain the denoised audio signal based on the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal according to the following steps:

[0124] The first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction are summed to obtain the noise-reduced frequency domain signal.

[0125] The denoised frequency domain signal is processed in the time domain to obtain the denoised audio signal.

[0126] In one possible implementation, the acquisition module 401 is configured to acquire the audio signal to be denoised according to the following steps:

[0127] In response to the headphone communication command of the true wireless stereo (TWS) earphones, the sound signal to be noise-reduced is acquired.

[0128] It should be noted that the apparatus in this embodiment can implement the various processes of the aforementioned method and achieve the same effects and functions, which will not be elaborated here.

[0129] This disclosure also provides an electronic device, such as... Figure 5 The diagram shown is a schematic representation of an electronic device structure provided in this embodiment of the present disclosure, including: a processor 501, a memory 502, and a bus 503. The memory 502 stores machine-readable instructions executable by the processor 501 (e.g., ...). Figure 4 The device includes modules 401 for acquiring data, 402 for frequency domain processing, 403 for first noise reduction, 404 for second noise reduction, and 405 for determining the corresponding execution instructions. When the electronic device is running, the processor 501 communicates with the memory 502 via the bus 503. When a machine-readable instruction is executed by the processor 501, the following processing is performed:

[0130] Acquire the audio signal to be noise-reduced;

[0131] Frequency domain processing is performed on the sound signal to obtain the frequency domain signal;

[0132] In response to a first sub-frequency domain signal with a frequency lower than a preset threshold in the frequency domain signal, the first sub-frequency domain signal is subjected to a first noise reduction process based on a pre-set attenuated microphone array to obtain a noise-reduced first sub-frequency domain signal.

[0133] In response to a second sub-frequency domain signal whose frequency is greater than or equal to a preset threshold in the frequency domain signal, a second noise reduction process is performed on the second sub-frequency domain signal based on a preset additive microphone array to obtain a noise-reduced second sub-frequency domain signal.

[0134] The denoised audio signal is obtained based on the first sub-frequency domain signal and the second sub-frequency domain signal after denoising.

[0135] This disclosure also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the microphone array noise reduction method described in the above-described method embodiments. The storage medium can be a volatile or non-volatile computer-readable storage medium.

[0136] This disclosure also provides a computer program product carrying program code. The program code includes instructions that can be used to execute the steps of the microphone array noise reduction method described in the above method embodiments. For details, please refer to the above method embodiments, which will not be repeated here.

[0137] The aforementioned computer program product can be implemented through hardware, software, or a combination thereof. In one optional embodiment, the computer program product is specifically embodied in a computer storage medium; in another optional embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0138] The various embodiments in this disclosure are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. In particular, the descriptions of the apparatus, device, and computer-readable storage medium embodiments are simplified because they are substantially similar to the method embodiments; relevant details can be found in the descriptions of the method embodiments.

[0139] The apparatus, device, and computer-readable storage medium provided in this disclosure correspond one-to-one with the method. Therefore, the apparatus, device, and computer-readable storage medium also have similar beneficial technical effects as their corresponding methods. Since the beneficial technical effects of the method have been described in detail above, the beneficial technical effects of the apparatus, device, and computer-readable storage medium will not be repeated here.

[0140] Those skilled in the art will understand that embodiments of this disclosure can be provided as methods, apparatus (devices or systems), or computer-readable storage media. Therefore, this disclosure can take the form of a completely hardware implementation, a completely software implementation, or an implementation combining software and hardware aspects. Furthermore, this disclosure can take the form of a computer-readable storage medium implemented on one or more computer-readable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-readable program code.

[0141] This disclosure is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (devices or systems), and computer-readable storage media according to embodiments of this disclosure. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0142] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0143] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0144] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0145] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0146] Computer-readable media, including both permanent and non-permanent, removable and non-removable media, can store information using any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device. Furthermore, although the operations of the methods of this disclosure are described in a specific order in the accompanying drawings, this does not require or imply that these operations must be performed in that specific order, or that all of the operations shown must be performed to achieve the desired result. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0147] While the spirit and principles of this disclosure have been described with reference to several specific embodiments, it should be understood that this disclosure is not limited to the disclosed specific embodiments, and the division of aspects does not imply that features in these aspects cannot be combined for benefit; such division is merely for convenience of expression. This disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A microphone array noise reduction method, applied to microphone arrays with limited physical size, characterized in that, include: Acquire the audio signal to be noise-reduced; The sound signal is processed in the frequency domain to obtain a frequency domain signal; In response to a first sub-frequency domain signal whose frequency is less than a preset threshold in the frequency domain signal, the first sub-frequency domain signal is subjected to a first noise reduction process based on a pre-set attenuated microphone array to obtain a noise-reduced first sub-frequency domain signal. The first noise reduction process includes: filtering the first sub-frequency domain signal at the first frequency point based on a pre-set low-pass filter to suppress white noise, wherein the passband bandwidth of the low-pass filter is positively correlated with the frequency of the first sub-frequency domain signal, and performing noise reduction on the filtered signal based on a differential microphone array (DMA). In response to a second sub-frequency domain signal in the frequency domain signal whose frequency is greater than or equal to a preset threshold, a second noise reduction process is performed on the second sub-frequency domain signal based on a pre-set additive microphone array to obtain a noise-reduced second sub-frequency domain signal; the second noise reduction process includes: noise reduction of the second sub-frequency domain signal based on a generalized sidelobe canceller (GSC); The noise-reduced second sub-frequency domain signal is delayed based on the number of taps of the low-pass filter to obtain the delayed second sub-frequency domain signal. Based on the first sub-frequency domain signal after noise reduction and the second sub-frequency domain signal after delay, the noise-reduced sound signal is obtained.

2. The method according to claim 1, characterized in that, The subtractive microphone array is a differential microphone array (DMA), and the additive microphone array is a generalized sidelobe canceller (GSC).

3. The method according to claim 2, characterized in that, The first noise reduction process, based on a pre-set attenuating microphone array, is applied to the first sub-frequency domain signal to obtain the noise-reduced first sub-frequency domain signal, including: For the first frequency point where the first sub-frequency domain signal is located, the first sub-frequency domain signal is filtered based on a pre-set low-pass filter to obtain the filtered first sub-frequency domain signal. The filtered first sub-frequency domain signal is subjected to a first noise reduction process based on a pre-set DMA to obtain the noise-reduced first sub-frequency domain signal.

4. The method according to claim 3, characterized in that, The obtained noise-reduced audio signal includes: Align the first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction to obtain the aligned first sub-frequency domain signal and second sub-frequency domain signal. Based on the aligned first sub-frequency domain signal and second sub-frequency domain signal, the noise-reduced audio signal is obtained.

5. The method according to claim 4, characterized in that, Aligning the denoised first sub-frequency domain signal and the denoised second sub-frequency domain signal includes: The second sub-frequency domain signal after noise reduction is delayed based on the number of taps of the low-pass filter to determine the delayed second sub-frequency domain signal. Based on the denoised first sub-frequency domain signal and the delayed second sub-frequency domain signal, the aligned first sub-frequency domain signal and second sub-frequency domain signal are obtained.

6. The method according to claim 1, characterized in that, The obtained noise-reduced audio signal includes: The first sub-frequency domain signal and the second sub-frequency domain signal after noise reduction are summed to obtain the noise-reduced frequency domain signal. The denoised frequency domain signal is processed in the time domain to obtain the denoised audio signal.

7. The method according to claim 1, characterized in that, The acquisition of the audio signal to be denoised includes: In response to the headphone communication command of the true wireless stereo (TWS) earphones, the sound signal to be noise-reduced is acquired.

8. A microphone array noise reduction device, applied to microphone arrays with limited physical size, characterized in that, include: The acquisition module is used to acquire the audio signal to be denoised; The frequency domain processing module is used to perform frequency domain processing on the sound signal to obtain a frequency domain signal; The first noise reduction module is used to respond to a first sub-frequency domain signal with a frequency less than a preset threshold in the frequency domain signal, and to perform a first noise reduction process on the first sub-frequency domain signal based on a preset attenuating microphone array to obtain the noise-reduced first sub-frequency domain signal. The first noise reduction process includes: filtering the first sub-frequency domain signal at the first frequency point based on a pre-set low-pass filter to suppress white noise, wherein the passband bandwidth of the low-pass filter is positively correlated with the frequency of the first sub-frequency domain signal, and performing noise reduction on the filtered signal based on a differential microphone array (DMA). The second noise reduction module is used to respond to a second sub-frequency domain signal with a frequency greater than or equal to a preset threshold in the frequency domain signal, and to perform a second noise reduction process on the second sub-frequency domain signal based on a preset additive microphone array to obtain a noise-reduced second sub-frequency domain signal; the second noise reduction process includes: performing noise reduction on the second sub-frequency domain signal based on a generalized sidelobe canceller (GSC). The determining module is used to perform delay processing on the noise-reduced second sub-frequency domain signal based on the number of taps of the low-pass filter to obtain the delayed second sub-frequency domain signal; and to obtain the noise-reduced sound signal based on the noise-reduced first sub-frequency domain signal and the delayed second sub-frequency domain signal.

9. A microphone array noise reduction system, applied to microphone arrays with limited physical size, characterized in that, include: Subtractive microphone arrays, additive microphone arrays, and processors; The processor is connected to both the subtractive microphone array and the additive microphone array. The processor is configured to acquire the audio signal to be denoised; perform frequency domain processing on the audio signal to obtain a frequency domain signal; the frequency domain signal includes a first sub-frequency domain signal with a frequency less than a preset threshold and a second sub-frequency domain signal with a frequency greater than or equal to the preset threshold; perform delay processing on the denoised second sub-frequency domain signal based on the number of taps of the low-pass filter to obtain a delayed second sub-frequency domain signal; and obtain a denoised audio signal based on the first sub-frequency domain signal denoised by the subtractive microphone array and the delayed second sub-frequency domain signal denoised by the additive microphone array. The subtractive microphone array is used to perform a first noise reduction process on the first sub-frequency domain signal to obtain a noise-reduced first sub-frequency domain signal. The first noise reduction process includes: filtering the first sub-frequency domain signal at the first frequency point based on a pre-set low-pass filter to suppress white noise, wherein the passband bandwidth of the low-pass filter is positively correlated with the frequency of the first sub-frequency domain signal, and performing noise reduction on the filtered signal based on a differential microphone array (DMA). The additive microphone array is used to perform a second noise reduction process on the second sub-frequency domain signal to obtain a noise-reduced second sub-frequency domain signal; the second noise reduction process includes: performing noise reduction on the second sub-frequency domain signal based on a generalized sidelobe canceller (GSC).

10. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory via the bus, and the machine-readable instructions, when executed by the processor, perform the microphone array noise reduction method as described in any one of claims 1 to 7.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the microphone array noise reduction method as described in any one of claims 1 to 7.

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