CN109275084B

CN109275084B - Method, device, system, equipment and storage medium for testing microphone array

Info

Publication number: CN109275084B
Application number: CN201811063803.6A
Authority: CN
Inventors: 刘孟美; 许凡; 蒋佳为; 张伟
Original assignee: Beijing Xiaomi Intelligent Technology Co Ltd
Current assignee: Beijing Xiaomi Intelligent Technology Co Ltd
Priority date: 2018-09-12
Filing date: 2018-09-12
Publication date: 2021-01-01
Anticipated expiration: 2038-09-12
Also published as: CN109275084A

Abstract

The present disclosure provides a method, an apparatus, a system, a device and a storage medium for testing a microphone array, wherein the method comprises: receiving an audio signal obtained by collecting a test audio by a microphone array; processing the audio signals to obtain single-channel designated parameters of the microphones and inter-channel designated parameters between the microphones; determining the performance of the microphone array according to the single-channel specified parameters and the inter-channel specified parameters, and outputting a performance test result; wherein the single channel specification parameters include: sensitivity level, sensitivity level curve, total harmonic distortion parameter, total harmonic distortion curve, noise level, signal-to-noise ratio, tolerance of frequency response, tightness parameter and clipping parameter; the inter-channel specifying parameters include: frequency response consistency parameters, time delay consistency parameters and correlation parameters. Therefore, the accuracy of the performance test result is improved, and the difficulty of the performance test of the microphone array is reduced.

Description

Method, device, system, equipment and storage medium for testing microphone array

Technical Field

The present disclosure relates to the field of test technologies for sound pickup devices, and in particular, to a method, an apparatus, a system, a device, and a storage medium for testing a microphone array.

Background

The microphone array is composed of a certain number of acoustic sensors (microphones) arranged according to a certain rule, is used for sampling and processing the spatial characteristics of a sound field, and is widely applied to artificial intelligence, such as different application scenes of an intelligent television, an intelligent air conditioner, a robot and the like.

However, due to the diversity of application scenarios, the microphone array needs to be adaptively adjusted, such as adjusting the installation manner of the microphone array, the cavity of the microphone, the sealing material, and/or the sealing manner; therefore, the sound pickup performance of the microphone array is uneven, which affects subsequent applications, for example, the subsequent algorithm research, adaptation and tuning are hindered, namely the commercialization process of the product; the performance of core function modules such as acoustic front-end processing, voice awakening and voice recognition is influenced.

Therefore, it is generally necessary to test the performance of a microphone array before it is installed in a factory or application. However, in the related art, the performance of only a single microphone is tested, and the sum of the performance test results of the microphones is used as the performance test result of the microphone array. Therefore, the related art does not perform reasonable performance test on the whole microphone array, neglects the influence of the relation among the microphones on the whole array, leads to the fact that the performance test result is more one-sided and inaccurate, and even if the performance test is qualified, the subsequent application can still be influenced.

Disclosure of Invention

To overcome the problems in the related art, the present disclosure provides a method, an apparatus, a system, a device, and a storage medium for testing a microphone array.

According to a first aspect of embodiments of the present disclosure, there is provided a method for testing a microphone array, the method including:

receiving an audio signal obtained by collecting a test audio by a microphone array;

processing the audio signals to obtain single-channel designated parameters of the microphones and inter-channel designated parameters between the microphones;

determining the performance of the microphone array according to the single-channel specified parameters and the inter-channel specified parameters, and outputting a performance test result;

wherein the single channel specification parameters include: sensitivity level, sensitivity level curve, total harmonic distortion parameter, total harmonic distortion curve, noise level, signal-to-noise ratio, tolerance of frequency response, tightness parameter and clipping parameter; the inter-channel specifying parameters include: frequency response consistency parameters, time delay consistency parameters and correlation parameters.

According to a second aspect of the embodiments of the present disclosure, there is provided a test apparatus of a microphone array, including:

a receiving module configured to: receiving an audio signal obtained by collecting a test audio by a microphone array;

a processing module configured to: processing the audio signals to obtain single-channel designated parameters of the microphones and inter-channel designated parameters between the microphones;

an output module configured to: determining the performance of the microphone array according to the single-channel specified parameters and the inter-channel specified parameters, and outputting a performance test result;

According to a third aspect of the embodiments of the present disclosure, there is provided a test system of a microphone array, including an audio source device, a speaker, and a computing device; the audio playing interface of the sound source equipment is in signal connection with the audio receiving interface of the loudspeaker; the audio input interface of the computing equipment is in signal connection with the audio output interface of the microphone array to be tested, and the computing equipment comprises the device;

before testing the microphone array to be tested, the pickup end of the microphone array to be tested is opposite to the pronunciation end of the loudspeaker, and the center of the pickup end and the pronunciation center of the loudspeaker are positioned on the same horizontal straight line.

According to a fourth aspect of the embodiments of the present disclosure, there is provided an electronic apparatus including:

a processor;

a memory for storing a computer program executable by the processor;

wherein the processor implements the steps of the aforementioned method when executing the program.

According to a fifth aspect of embodiments of the present disclosure, there is provided a computer readable storage medium, having stored thereon a computer program, which when executed by a processor, performs the steps of the aforementioned method.

Therefore, the technical scheme provided by the embodiment of the disclosure can have the following beneficial effects:

determining a plurality of parameters which have great significance on the performance evaluation of the microphone array through a plurality of explorations and practices of creative labor in the early stage; therefore, in the testing process, the single-channel designated parameters of each microphone and the inter-channel designated parameters between the microphones are obtained according to the plurality of parameters determined in the early stage, and the performance of the microphone array to be tested can be determined based on the obtained single-channel designated parameters and the inter-channel designated parameters in the follow-up process, so that the accuracy of the performance testing result is improved, and the difficulty of the performance testing of the microphone array is reduced.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

FIG. 1 is a schematic diagram of an application scenario of an embodiment of the present disclosure;

fig. 2 is a flow chart illustrating a method of testing a microphone array according to an exemplary embodiment of the present disclosure;

FIG. 3 is a schematic diagram of a test audio shown in accordance with an exemplary embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a human-machine interface of application software for testing microphone array performance shown in accordance with an exemplary embodiment of the present disclosure;

FIG. 5 is an interface diagram illustrating a pop-up configuration audio file application interface after a browse control G has been clicked on according to an illustrative embodiment of the present disclosure;

fig. 6 is a block diagram illustrating a test apparatus for a microphone array according to an exemplary embodiment of the present disclosure;

fig. 7 is a block diagram illustrating a test apparatus for a microphone array according to an exemplary embodiment of the present disclosure;

fig. 8 is a block diagram illustrating an electronic device of a testing apparatus of a microphone array according to an exemplary embodiment of the present disclosure.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

It is to be understood that although the terms first, second, third, etc. may be used herein to describe various information, such information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure. The word "if" as used herein may be interpreted as "at … …" or "when … …" or "in response to a determination", depending on the context.

The embodiment of the disclosure provides a novel test method of a microphone array, and a plurality of parameters which have great significance to the performance evaluation of the microphone array are determined through a plurality of explorations and practices of creative labor in the early stage; therefore, in the testing process, the single-channel designated parameters of each microphone and the inter-channel designated parameters between the microphones are obtained according to the plurality of parameters determined in the early stage, and the performance of the microphone array to be tested can be determined based on the obtained single-channel designated parameters and the inter-channel designated parameters in the follow-up process, so that the accuracy of the performance testing result is improved, and the difficulty of the performance testing of the microphone array is reduced.

Fig. 1 shows a schematic diagram of an application scenario of an embodiment of the present disclosure, in which a sound source device plays a test audio through a speaker S; the microphone array M to be tested converts the received test audio into an audio signal and transmits the audio signal to the computing equipment; the computing device analyzes the audio signal to obtain a plurality of performance evaluation parameters to determine the performance of the microphone array under test. The sound source device and the computing device may be the same device, for example, a computer device may be used as a sum of the sound source device and the computing device, that is, the computer device is not only responsible for playing the test audio, but also responsible for analyzing and processing the audio signal.

In the following, the formation process of the aforementioned application scenario is briefly described:

the microphone array to be tested and the loudspeaker with the qualified power and the small distortion are placed in a free field environment meeting the testing requirements, such as an anechoic chamber, through a support. Wherein, the test requirements that the environment needs to meet include: the ambient air pressure is at standard atmospheric pressure and the ambient temperature is normal air temperature. The distance between the microphone array to be tested and the loudspeaker can be one meter, and the distance between the microphone array to be tested and the loudspeaker can be changed according to actual needs. The position relation between the microphone array to be tested and the loudspeaker also needs to satisfy the following conditions: the sound pickup end of the microphone array to be tested is opposite to the sound production end of the loudspeaker, and the center of the sound pickup end and the sound production center of the loudspeaker are located on the same horizontal straight line, so that the sound collecting holes of the microphones in the microphone array to be tested are opposite to the loudspeaker. In addition, in order to better improve the test accuracy, the pickup end of the microphone array to be tested needs to exceed the support for supporting the pickup end, that is, the pickup end protrudes toward the speaker direction compared with the support panel of the support, so as to prevent the sound reflected by the support from affecting the performance test of the microphone array to be tested.

Before testing the performance of the microphone array to be tested, the sound pressure level of the position of the microphone array to be tested is calibrated by adopting an alternative method. During calibration, the microphone array to be tested is removed, and the standard sound pickup equipment is placed at the original position of the microphone array to be tested. Then, the sound source equipment plays a sinusoidal signal with the test audio frequency of 1kHz and 0dB through a loudspeaker; and the standard sound pickup equipment collects the sinusoidal signal and outputs the sinusoidal signal to the computing equipment, and the computing equipment judges whether the sound pressure level of the signal is the standard sound pressure level-94 dB SPL or not according to the received signal. And if the sound pressure level of the sinusoidal signal collected by the standard sound pickup equipment is a non-standard sound pressure level, adjusting the volume gains of the sound source equipment and the loudspeaker until the sound pressure level at the standard sound pickup equipment is the standard sound pressure level. After the sound pressure level of the standard sound equipment is adjusted, the standard sound equipment is removed, and the microphone array to be tested is placed.

In addition, in order to ensure the stability of the system, after the microphone array to be tested is placed, the loudspeaker and the microphone array to be tested are started before the performance test, so that the audio played by the loudspeaker and the audio collected by the microphone last for 10s, and the preheating is completed.

Therefore, the application scene can be formed through the operation.

As shown in fig. 2, fig. 2 is a flowchart illustrating a testing method of a microphone array according to an exemplary embodiment of the present disclosure, which may be used in a terminal, the method including the steps of:

and S101, receiving an audio signal obtained by collecting the test audio by the microphone array.

And S102, processing the audio signals to obtain single-channel specified parameters of the microphones and inter-channel specified parameters between the microphones.

S103, determining the performance of the microphone array according to the single-channel specified parameters and the inter-channel specified parameters, and outputting a performance test result.

Wherein the single channel specification parameters include: sensitivity level, sensitivity level curve, noise level, total harmonic distortion parameter, total harmonic distortion curve, signal-to-noise ratio, tolerance of frequency response, tightness parameter and clipping parameter; the inter-channel specifying parameters include: frequency response consistency parameters, time delay consistency parameters and correlation parameters.

In the present disclosure, the single-channel specification parameter is used to evaluate partial performance of the microphone array based on performance of a single microphone, for example, when the microphone array is composed of n microphones, the single-channel specification parameters of the n microphones need to be acquired respectively, and performance of the n microphones needs to be evaluated respectively, as one of the parts for evaluating performance of the microphone array. And the inter-channel specified parameters are directly used as another part for evaluating the performance of the microphone array and are used for representing the relation among the channels of the microphone array.

The test audio is played by sound source equipment through the pronunciation end of the loudspeaker and is collected by the pickup end of the microphone array. The sound source device can be a computer, a mobile phone device, an audio playing device, a tablet device and other terminal devices. The test audio includes at least one of: the noise suppression device comprises single-frequency sinusoidal signals of 1kHz and 0dB, a single-frequency sinusoidal signal sequence of which the 1kHz and the sound pressure level are sequentially reduced from 0dB to a preset sound pressure level by taking-2 dB as a tolerance and the break time between every two adjacent groups of signals is a preset value, a mute signal, logarithmic frequency sweep signals of 20 Hz-20 kHz and 0dB, and a white noise signal sequence of which the 0dB white noise signal continuously lasts for the preset time is changed to a white noise signal sequence of which the sound pressure level is gradually reduced from 120dB by taking-3 dB as a tolerance.

In this embodiment, in order to improve the performance testing efficiency, the single-frequency sinusoidal signal is continuously played for 10s during the testing process; the single-frequency sinusoidal signal sequence comprises 15 groups of single-frequency sinusoidal signals, each group of single-frequency sinusoidal signals is continuously played for 3s, the preset sound pressure level is-28 dB, and the preset value is 2 s; the logarithmic sweep frequency signal is continuously played for 10 s; the white noise signal is continuously played for 10 s; the white noise signal sequence is continuously played for 10 s.

However, in other embodiments, the continuous playing time of each signal, the preset sound pressure level and the preset value may be changed according to the test requirements.

In this embodiment, to simplify the operation of playing the test audio in the test process and further improve the performance test efficiency, the single-frequency sinusoidal signal sequence, the mute signal, the logarithmic frequency sweep signal, the white noise signal, and the white noise signal sequence may be integrated into the same segment of audio to form the test audio including all signals required in the performance test. For example, as shown in fig. 3, fig. 3 is a schematic diagram of a test audio according to an exemplary embodiment of the present disclosure, in fig. 3, a reference sign a indicates a waveform diagram of the test audio, a reference sign B indicates a spectrogram of the test audio, a signal in an area where a reference sign C is located is a white noise signal, a signal in an area where a reference sign D is located is a logarithmic sweep signal, and a signal in an area where a reference sign E is located is a sinusoidal signal. At this time, in the process of processing a whole segment of audio signal collected by the microphone array, the computing device needs to identify and divide the whole segment of audio signal into several segments of sub-audio signals, so as to obtain corresponding parameters according to different sub-audio signal processing. Here, the signal division may be implemented according to a time interval between signals, for example, a termination time of one signal and a start time of another signal, or a signal for identifying division may be inserted between every two adjacent signals as an identification mark, thereby implementing the signal division.

Of course, in other variant embodiments, the single-frequency sinusoidal signal sequence, the mute signal, the logarithmic frequency sweep signal, the white noise signal, and the white noise signal sequence may be respectively integrated into different audio frequencies to form a plurality of test audio frequencies.

In order to improve the calculation efficiency of the above parameters, in this embodiment, the step S102 includes at least one of the following steps Sa to Sh:

and Sa, acquiring the sensitivity level of each microphone, comprising steps Sa 1-Sa 2.

Sa1, when the test audio frequency is a single-frequency sinusoidal signal with 1kHz and 0dB, acquiring the output voltage of the audio signal collected by each microphone;

sa2 calculates the sensitivity level of each microphone based on each output voltage and the preset input sound pressure.

Wherein the step Sa2 includes steps Sa21 and Sa 22:

sa21, calculating the ratio of each output voltage to the preset input sound pressure to obtain the sensitivity of each microphone;

sa22, with a base 10, calculates the product of 20 and the logarithm of each sensitivity, and obtains the sensitivity level of each microphone.

In this embodiment, the sensitivity represents: effective value U of output voltage of single channel (one microphone) and standard sound pressure P₀Wherein the standard sound pressure P₀Is 94dB SPL, i.e., the preset input sound pressure is the standard sound pressure. Then, the sensitivity level S of a single channel can be calculated by the following formula: 201g (U/P)₀)。

Then, when the sensitivity level of each microphone in the microphone array needs to be measured, a single-frequency sinusoidal signal of 1kHz, 0dB can be played for 10s through the speaker by using the sound source device, so that the microphone array collects the current test audio and inputs the current test audio into the computing device. The computing device may process the audio signals currently acquired by the microphone array according to steps Sa 1-Sa 2 to obtain the sensitivity level of each microphone.

And Sb, acquiring a sensitivity curve of each microphone, wherein the steps of Sb 1-Sb 2 are included.

Sb1, when testing a single-frequency sinusoidal signal sequence with the audio frequency of 1kHz, the sound pressure level sequentially reduced from 0dB to a preset sound pressure level by taking-2 dB as a tolerance, and the interruption time between every two adjacent groups of signals is a preset value, calculating the sensitivity level of each microphone array on each single-frequency sinusoidal signal;

and Sb2, generating a curve of the sensitivity level changing along with the sound pressure level according to the sensitivity level of each microphone at each single-frequency sinusoidal signal, and obtaining the sensitivity curve of each microphone.

Optionally, the preset sound pressure level is-28 dB, and the preset value is 2 s. It can be seen that the sequence of single-frequency sinusoidal signals in step Sb1 has 15 sets of single-frequency sinusoidal signals with the same frequency but different sound pressure levels. In addition, in the step Sb1, the steps Sa1 to Sa2 are shown in the calculation manner of the sensitivity level of each single-frequency sinusoidal signal of each microphone array, which is not described herein again.

In this embodiment, the sensitivity curve is used to measure the sound-to-electricity conversion capability of a single channel under single-frequency sinusoidal signals with different sound pressure levels.

Then, when the sensitivity level curve of each microphone in the microphone array needs to be measured, a sound source device can be used to play a single-frequency sinusoidal signal of 1kHz and 0dB for 3 seconds continuously through a loudspeaker, and then play a mute signal for 2 seconds or stop playing any audio for 2 seconds; then playing a single-frequency sinusoidal signal of 1kHz and-2 dB for 3s continuously, and then playing a mute signal for 2s or stopping playing any audio for 2 s; then playing a single-frequency sinusoidal signal of 1kHz and-4 dB for 3s continuously; therefore, according to the rule, the single-frequency sinusoidal signals which are 2dB lower than the sound pressure level of the previous single-frequency sinusoidal signal are played at the time interval of 2s in sequence until the sound pressure level of the currently played single-frequency sinusoidal signal is reduced to-28 dB. So that the microphone array can capture audio signals having different sound pressure levels and input them into the computing device. The computing device may process the audio signal currently acquired by the microphone array according to steps Sb 1-Sb 2 to obtain a sensitivity level curve for each microphone.

And Sc, acquiring total harmonic distortion parameters of each microphone, including step Sc 1.

And Sc1, when the test audio is a single-frequency sinusoidal signal with 1kHz and 0dB, calculating to obtain the total harmonic distortion parameters of each microphone according to the audio signals collected by each microphone.

In this embodiment, the total harmonic distortion parameter represents: the effective value of the harmonic component in the output voltage as a percentage of the total voltage containing the fundamental frequency component. The total harmonic distortion parameter THD can be calculated by the following formula:

wherein, U_nfVoltage effective value, U, representing the nth harmonic component_tRepresenting the effective value of the total voltage at the fundamental frequency.

Then, when the total harmonic distortion parameters of each microphone need to be tested, the sound pressure level at the microphone array is adjusted from 94dB SPL to 106dB SPL, and then the single-frequency sinusoidal signal of 1kHz and 0dB is played through the loudspeaker for 10 seconds by using the sound source device, so that each microphone collects the current audio signal and inputs the current audio signal to the computing device. The computing device can calculate the total harmonic distortion parameters of each microphone according to the step Sc 1.

And Sd, acquiring a total harmonic distortion curve of each microphone, including step Sd 1.

Sd1, when testing a single-frequency sinusoidal signal sequence in which the audio frequency is 1kHz, the sound pressure level is sequentially reduced from 0dB to a preset sound pressure level by taking-2 dB as a tolerance, and the interruption time between every two adjacent groups of signals is a preset value, calculating the total harmonic distortion parameter of the audio signal at each sound pressure level according to the audio signal collected by each microphone, and generating a total harmonic distortion curve.

The meaning of the test audio in the step Sd1 is the same as that of the test audio in the step Sb1, and is not described herein. However, before the total harmonic distortion curve of each microphone needs to be measured, the sound pressure level at the microphone array must be adjusted from 94dB SPL to 106dB SPL.

In this embodiment, the total harmonic distortion curve is a curve in which harmonic distortion varies with sound pressure level, and is used to reflect a harmonic distortion condition generated when each microphone acquires a single-frequency sinusoidal signal with different sound pressure levels.

Se, obtaining the noise level of each microphone, comprising steps Se1 and Se 2.

Se1, when the test audio is a mute signal or the test audio is paused to be played, acquiring the total voltage energy of the noise signals collected by each microphone;

and Se2, respectively calculating the total energy of the full frequency band of each microphone based on the total energy of each voltage, wherein the total energy of the full frequency band is the noise level.

In this embodiment, the noise level represents: under a quiet environment, the energy of a noise signal output by a single channel is in dB.

The step Se2 includes: and taking 10 as a base, respectively calculating the product of the logarithm of the total energy of each voltage and 10 to obtain the total energy of the full frequency band of each microphone. It can be known that the noise level of each microphone, i.e. the total energy GN of the full frequency band, can be calculated by the following formula: GN 20lgE_noise；E_noiseThe total energy of the voltage output by the single microphone from the beginning to the end of the acquisition is shown, and the obtaining manner thereof is known from the related art and will not be described herein.

Then, when it is desired to measure the noise level of each microphone in the microphone array, the sound source device may be used to play a mute signal through the speaker or to stop playing any audio so that the microphone array operates in a quiet environment, and the collected noise signal may be input to the computing device. The computing device may process the noise signal currently collected by the microphone array according to steps Se 1-Se 2 to obtain the noise level of each microphone.

Sf, acquiring the signal-to-noise ratio of each microphone, comprising step Sf 1.

Sf1, calculating the difference between the sensitivity level of each microphone and the noise level thereof, and obtaining the signal-to-noise ratio of each microphone.

In this embodiment, the snr represents: the energy ratio of the target signal to the noise signal is in dB as the product of the base 10 logarithm and 10. That is, the SNR of each microphone can be calculated by the following formula: SNR is S-GN. Wherein, the acquisition process of the calculation formula of the signal-to-noise ratio SNR is as follows:

after the sensitivity level and the noise level of each microphone are obtained through steps Sa and Se, the signal-to-noise ratio of each microphone can be directly calculated by using the obtained data, so as to further simplify the calculation steps of the parameters and improve the calculation efficiency of the parameters.

Sg, the tolerance of the frequency response of each microphone is obtained, including steps Sg1 and Sg 2.

Sg1, when the test audio frequency is logarithmic sweep frequency signals of 20 Hz-20 KHz and 0dB, generating a frequency response curve according to the audio signals collected by each microphone;

sg2, calculating the difference between the maximum value and the minimum value of each frequency response curve, and obtaining the tolerance of the frequency response of each microphone.

In this embodiment, the frequency response curve represents: single channel sensitivity level versus test audio frequency. According to the step Sg1, the frequency range of the obtained frequency response curve is the same as the frequency range of the test audio, namely 20 Hz-20 kHz; in this frequency range, the frequency response corresponding to each frequency point has a value corresponding to the sensitivity level. In the step Sg2, the maximum value represents a maximum frequency response value of the frequency response curve, and the minimum value represents a minimum frequency response value of the frequency response curve. In one embodiment, to improve the accuracy of the obtained frequency response tolerance, the maximum and minimum values of each frequency curve are the maximum and minimum frequency response values of the frequency response curve within 100 Hz-8 kHz, respectively.

Then, when the noise level of each microphone in the microphone array needs to be measured, the logarithmic frequency sweep signal of 20 Hz-20 kHz and 0dB can be played for 10s through the loudspeaker by using the sound source device, so that the microphone array collects the current test audio, and the collected audio signal is input into the computing device. The computing device may process the audio signal currently acquired by the microphone array according to steps Sg 1-Sg 2 to obtain the frequency response tolerance of each microphone.

Sh, acquiring the external sealing parameters in the sealing parameters of the microphones, wherein the steps Sh 1-Sh 2 are included.

Sh1, when the test audio is a white noise signal of 0dB, calculating first single-frequency point energy of each frequency point of the audio signal collected by each microphone when the sound receiving hole is not sealed, and calculating second single-frequency point energy of each frequency point of the audio signal collected by each microphone when the sound receiving hole is sealed;

sh2, calculating to obtain the single-frequency point energy difference mean value of each microphone based on the first single-frequency point energy and the second single-frequency point energy, wherein the single-frequency point energy difference mean value is the external sealing parameter in the sealing parameter.

In this embodiment, the external sealing property parameter is used to reflect the sound transmission performance of the external non-acoustic opening of the microphone array, and the unit is dB.

In one embodiment, the step Sh1 may include: when the test audio is a white noise signal of 0dB, calculating the energy average value of each frequency point of the audio signal collected by each microphone when the sound receiving hole is not sealed to obtain a first single-frequency point energy average value; calculating the energy average value of each frequency point of the audio signal acquired by each microphone when the sound receiving hole is sealed to obtain a second single-frequency point energy average value; the step Sh2 may include: calculating to obtain the mean value of the energy difference of the single frequency points of each microphone based on the first mean value of the energy of the single frequency points and the second mean value of the energy of the single frequency points of each microphone; the single-frequency point energy difference mean value is the external tightness parameter.

First single frequency point energy mean value E of each microphone_openCan be calculated by the following formula:

wherein E is_open-allRepresenting the total energy of the output signal of the current microphone under the full frequency band; omega_allRepresenting the full frequency band of the output signal of the current microphone. In addition, the energy mean value E of the second single frequency point of each microphone_sealedThe calculation principle of (2) can refer to the calculation principle of the energy of the first single frequency point, and is not described herein again.

In the step Sh2, the single-frequency-point energy difference mean ES of each microphone may be calculated by the following formula:

then, when it is necessary to measure the external sealability parameters of the respective microphones in the microphone array, a white noise signal of 0dB is played through the speaker for 10 seconds using the sound source device. The microphone array collects audio signals and inputs the audio signals into the computing equipment under normal conditions (the sound receiving hole is not sealed) and under the condition that the sound receiving hole is physically sealed. The computing equipment can process the two audio signals according to the steps Sh 1-Sh 2 to obtain the external sealing performance parameters of each microphone.

In another embodiment, the step Sh1 may include the step Sh11, and the step Sh2 may include Sh21 and Sh 22.

Sh11, when the test audio is a white noise signal of 0dB, calculating the energy of each frequency point of the audio signal collected by each microphone when the sound receiving hole is not sealed, and obtaining the energy of a first single frequency point; and calculating the energy of each frequency point of the audio signal collected by each microphone when the sound receiving hole is sealed to obtain the energy of the second single frequency point.

Sh21, based on all the first single-frequency point energies and all the second single-frequency point energies, calculates the single-frequency point energy difference of each frequency point of each microphone. Wherein, the single-frequency energy difference ES1 can be calculated by the following formula:

said E_0-allIs the sum of all first single frequency point energies; said E_s-allIs the sum of all the second single-frequency point energies.

Sh22, calculating the ratio of the sum of all single-frequency point energy differences to the full frequency band to obtain the single-frequency point energy difference mean value of each microphone, wherein the single-frequency point energy difference mean value is the external sealing parameter in the sealing parameters. The single-frequency point energy difference mean value ES can be calculated by the following formula:

ω_allrepresenting the full frequency band of the output signal of the current microphone.

And Si, acquiring time delay consistency parameters of the microphone array, wherein the time delay consistency parameters comprise steps Si 1-Si 2.

Si1, when the test audio is a white noise signal of 0dB, calculating the time delay difference between the audio signals collected by every two microphones according to the audio signals collected by each microphone;

and Si2, calculating the average value of all the time delay differences to obtain the time delay consistency parameter of the microphone array.

The time delay difference m between every two microphones can be calculated by the following formula:

wherein x and y respectively represent signals collected by two microphones (output signals of two channels), N is signal length, and R is signal length_xy(m) is the phase of two channelsAnd (7) closing the value. In the above formula, when R_xy(m) when the maximum value is obtained, the current value of m is the time delay difference between the two current microphones.

In addition, the quotient of the sum of all the delay differences and the total number of all the delay differences is calculated, so that the average value of all the delay differences can be obtained, and the average value is the multichannel delay consistency parameter.

Then, when the time delay consistency parameter of the microphone array needs to be measured, the white noise signal of 0dB is played continuously for 10s through the loudspeaker by using the sound source device, so that the microphone array collects the audio signal and inputs the audio signal to the computing device. The computing equipment can process the audio signals according to the steps Si 1-Si 2 to obtain the time delay consistency parameters of the microphone array.

Sj, obtaining correlation parameters of the microphone array, including steps Sj 1-Sj 2.

Sj1, when the test audio is a white noise signal of 0dB, calculating the correlation coefficient between the audio signals collected by every two microphones according to the audio signals collected by each microphone;

and Sj2, calculating the average value of all correlation coefficients to obtain the correlation parameters of the microphone array.

In this embodiment, the correlation represents the degree of correlation between signals of any two channels in the microphone array.

The correlation coefficient CC of the signals between every two channels can be calculated by the following formula:

wherein X and Y respectively represent output signals of two channels, E (XY) represents expectation of signal XY, E (X) represents expectation of signal X, E (Y) represents expectation of signal Y, rho_XRepresenting the mean square error, p, of the signal X_YRepresenting the mean square error of the signal Y.

In addition, the quotient of the sum of all correlation coefficients and the total number of all correlation coefficients is calculated, so that the average value of all correlation coefficients can be obtained, and the average value is the correlation parameter of multiple channels.

Then, when the correlation of the microphone array needs to be measured, a white noise signal of 0dB is played through the loudspeaker for 10s by using the sound source device, so that the microphone array collects the audio signal and inputs the audio signal to the computing device. The computing device can process the audio signals according to the steps Sj 1-Sj 2 to obtain the correlation parameters of the microphone array.

Sk, acquiring the clipping parameters of each microphone, and comprising steps Sk 1-Sk 2.

Sk1, when the test audio is a white noise signal sequence which changes from 0dB white noise signal lasting for the preset time to a white noise signal sequence whose sound pressure level is gradually reduced from 120dB by taking-3 dB as a tolerance, generating a signal waveform diagram according to the audio signals collected by each microphone;

sk2, determining the sound pressure level when the audio signal collected by each microphone is amplitude-cut according to each signal oscillogram, and obtaining the amplitude-cut parameter.

In this embodiment, the cropping is defined as: because the amplitude of the signal waveform is too large, the waveform exceeds the linear range of the system.

Then, when the clipping parameters of each microphone need to be measured, the white noise signal of 0dB is played continuously for 10s through the speaker by using the sound source device, and then the speaker is adjusted to gradually lower the sound pressure level of the played white noise signal from 120dB at every 3dB frequency, so that each microphone collects the audio signal and inputs the audio signal to the computing device. The computing device can judge whether the clipping phenomenon occurs to each channel according to the steps Sk 1-Sk 2, and the sound pressure level when the clipping occurs to each channel is used as the clipping parameter.

And SL, acquiring frequency response consistency parameters of the microphone array, wherein the SL comprises steps SL1 a-SL 2 a.

SL1a, calculating the average value of all frequency responses corresponding to each frequency point according to all frequency response curves to obtain the multichannel frequency response average value of each frequency point;

SL2a, calculating the difference between the frequency response of each frequency point of each frequency response curve and the corresponding multichannel frequency response mean value to obtain the mean value error of the frequency response of each frequency point of each frequency response curve, and generating the curve of the mean value error of the frequency response of each microphone along with the change of frequency in the same image to obtain a frequency response consistency curve among channels; and the inter-channel frequency response consistency curve is a frequency response consistency parameter.

In this embodiment, the frequency response consistency represents a frequency response difference between channels, and is used to reflect a deviation of frequency response characteristics between the channels.

The meaning of the multichannel frequency response mean value of each frequency point is described as follows:

assuming that the microphone array is composed of N microphones, i.e. there are N channels, based on the signals collected by the microphone array, N frequency response curves can be obtained. If the frequency response of each frequency response curve at the frequency omega is S respectively₁(ω)、 S₂(ω)、…S_N(ω), then, the mean of the multi-channel frequency response at frequency ω, that is, the frequency point

Can be calculated by the following formula:

where ω ∈ (0, 8kHz), ch denotes the flag of the current channel, and ch ═ 1, 2, 3, …, N.

Next, the meaning of the mean error of the frequency response of each frequency response curve for each frequency point is described:

based on the above example, the mean error of the frequency response of each frequency response curve at the frequency point of the frequency ω

Can be calculated by the following formula:

the frequency response consistency parameter, i.e. the inter-channel frequency response consistency curve, obtained through the steps SL1a and SL2a may be displayed on a display screen, so as to be observed by a tester to judge the frequency response characteristics of the microphone array.

In another embodiment, the obtaining of the frequency response consistency parameter of the microphone array may be implemented in other manners, please refer to the following steps SL1b to SL4 b.

SL1b, calculating the average value of all frequency responses corresponding to each frequency point according to all frequency response curves to obtain the multichannel frequency response average value of each frequency point;

SL2b, calculating the absolute value of the difference between the frequency response of each frequency point of each frequency response curve and the corresponding multichannel frequency response mean value, and obtaining the module value of the mean value error of the frequency response of each frequency point of each frequency response curve;

SL3b, calculating the average value of all the modulus values corresponding to each frequency point to obtain the modulus value average value of each frequency point;

SL4b, dividing all frequency points into continuous 3 frequency bands according to the order of magnitude, calculating the quotient of the sum of all module value mean values of each frequency band and the bandwidth of the frequency band respectively, and obtaining the frequency response module mean value of each frequency band; and the frequency response mode mean value is a frequency response consistency parameter.

The frequency response consistency parameter, namely the frequency response mode average value, obtained through the steps SL3 to SL6 can be directly applied by a computing device, so that the judgment of the frequency response characteristic of the microphone array is automatically realized.

For the description of the SL1b, reference may be made to the aforementioned description of the SL1a, which is not repeated herein.

In the step SL2b, a modulus a (ω) of the mean error of the frequency response of each frequency point of each frequency response curve is the mean error

The absolute value of (a), namely:

in the step SL3B, the mean value B (ω) of the modulus values of each frequency point may be calculated by the following formula:

in the step SL4b, optionally, the 3 frequency bands are (100Hz, 400 Hz) respectively]、(400Hz，3400Hz]And (3400Hz, 8000 Hz)]. The frequency response mode mean value FRC of each frequency band can be calculated by the following formula:

wherein, ω is₁Indicating the starting frequency, omega, of the current frequency band₂Representing the cutoff frequency of the current band.

Thereby, the above-mentioned acquisition of parameters can be achieved through steps Sa to SL. However, in other embodiments, there are other ways that the above parameters may be obtained, in which case one or more of the steps Sa to SL may be replaced by other calculation ways in the related art, and the step S102 is not limited to one or more of the steps Sa to SL. However, it should be clear that the steps Sa to SL can better improve the efficiency of acquiring the parameters and reduce the amount of calculation of the parameters.

In addition, the present disclosure does not limit the sequence of the steps Sa to SL, that is, in other embodiments, the execution sequence of the steps Sa to SL may be adaptively adjusted according to the logical relationship between the steps Sa to SL, and the execution sequence is not unique.

In step S103, each parameter obtained in step S102 may be compared with a corresponding preset parameter threshold, so as to respectively determine whether each parameter meets a preset requirement; the preset parameter thresholds may be preset by a tester according to experience, and are not described herein. The performance test results include pass or fail. And the performance test result is qualified only when all the parameters meet the preset requirement.

However, in another embodiment, the performance of the microphone array under test may be evaluated in a graded manner, for example, the performance test results may include: unqualified, qualified, medium, good and excellent. Suitably, each preset parameter threshold comprises: a qualifying threshold, a medium threshold, a good threshold, and an excellent threshold.

In an embodiment, to improve the accuracy of the microphone performance evaluation, the single-channel specified parameter further includes a frequency band single-frequency point energy mean value. The step S102 may further include the steps of:

sm, acquiring the frequency band single frequency point energy average value of each microphone, comprising a step Sm 1.

Sm1, when the test audio is a mute signal or the test audio is paused to play, dividing the working frequency band of each microphone into 3 continuous frequency bands, respectively calculating the energy average value of each frequency point of the noise signal collected by each microphone in each frequency band, and obtaining the frequency band single frequency point energy average value of each frequency band of each microphone.

In one embodiment, the operating frequency band of each microphone is adjusted to (0, 8kHz)]Is divided into (0, 80 Hz)]、(80，4kHz]And (4kHz, 8kHz)]These 3 bands. The average value GN of the energy per frequency band_fCan be calculated by the following formula:

where E (ω) is the signal energy at frequency ω, ω₁Indicating the starting frequency, omega, of the current frequency band₂Representing the cutoff frequency of the current band.

Then, when the frequency band single-frequency point energy average value of each microphone needs to be tested, the sound source device may be used to play a mute signal through the speaker or stop playing any audio, so that the microphone array operates in a quiet environment, and the acquired noise signal is input into the computing device. The computing device can process the noise signal currently acquired by the microphone array according to the step Sm1 to obtain the frequency band single frequency point energy average value of each frequency band of each microphone.

When the performance is judged, whether the energy mean value of the single frequency point of each frequency band meets the preset requirement needs to be judged. And if the energy mean value of the single frequency point of one frequency band does not meet the preset requirement, evaluating the performance of the microphone to be unqualified.

However, in other embodiments, the allowable number of the energy mean values of the frequency bands that do not meet the preset requirement may be appropriately adjusted according to the actual application requirements of the microphone array, that is, as long as the number of the energy mean values of the frequency bands that do not meet the preset requirement does not exceed the specified number, the performance test result of the microphone may not be affected.

In an embodiment, to further improve the accuracy of the microphone performance evaluation, based on any of the foregoing embodiments, the sealing parameter may further include an internal sealing parameter. The step S102 may further include the steps of:

and Sn, acquiring internal sealing performance parameters of each microphone, wherein the steps Sn 1-Sn 2 are included.

Sn1, when the test audio is a white noise signal of 0dB, calculating the energy average value of the audio signal at each frequency point collected by each microphone when the sound receiving hole is sealed, and obtaining the energy average value of a third single frequency point;

when the test audio is a mute signal or stops playing, calculating the energy average value of the signal collected by each microphone when the sound receiving hole is sealed at each frequency point to obtain the energy average value of a fourth single-frequency point;

sn2, calculating to obtain an inner single-frequency point energy difference average value based on the third single-frequency point energy average value and the fourth single-frequency point energy average value of each microphone; and the average value of the energy difference of the inner single-frequency points is the inner sealing performance parameter.

In this embodiment, the internal sealing performance parameter is used to reflect the internal sound transmission performance of the microphone array, and the unit is dB. In addition, the third single-frequency point energy mean value E of each microphone_interAnd a fourth single frequency point energy mean value E_noise/alllThe calculation principle of (2) can refer to the calculation principle of the energy of the first single frequency point, and is not described herein in detail.

In step Sn2, the calculation formula of the average value IS of the energy difference of the inner single frequency point of each microphone may be:

then, when the internal sealing parameters of each microphone in the microphone array need to be measured, the volume of the loudspeaker is firstly adjusted to 94dB SPL @1kHz, then 0dB white noise signal is continuously played for 10s through the loudspeaker by using sound source equipment, and then a mute signal is played or any audio is stopped playing. So that the microphone array collects signals under the two conditions when the sound receiving hole is physically sealed and inputs the signals to the computing equipment. The computing equipment can process the two audio signals according to the steps Sn 1-Sn 2 to obtain the internal sealing performance parameters of each microphone.

In an embodiment, to further improve the accuracy of the microphone performance evaluation, based on any of the foregoing embodiments, the inter-channel specific parameter may further include a phase consistency parameter. The step S102 may further include the steps of:

and So, acquiring phase consistency parameters of the microphone array, wherein the phase consistency parameters comprise steps So 1-So 2.

So1, when the test audio is logarithmic sweep frequency signal of 20 Hz-20 kHz and 0dB, generating corresponding phase curves according to the audio signals collected by each microphone respectively;

and So2, determining the similarity of the phase curves according to all the phase curves to obtain a phase consistency parameter.

In this embodiment, the similarity between all the phase curves is used as the phase consistency parameter. And the phase consistency parameter is used for reflecting the phase deviation among all channels of the microphone array.

In an embodiment, how to generate a corresponding phase curve according to the audio signals collected by each microphone can be seen in the related art; how to determine the similarity between curves according to all phase curves can also be seen in the related art; and will not be described in detail herein. All the phase curves can be integrated in the same graph to be displayed, at this time, a tested person can judge the similarity between the curves according to experience, or the similarity between the phase curves can be calculated through calculating equipment, so that the phase consistency parameters and the test result are output.

Then, when the phase consistency parameters of the microphone array need to be measured, the logarithmic frequency sweep signals of 20 Hz-20 kHz and 0dB are played continuously for 10s through the loudspeaker by using the sound source equipment. Such that the microphone array captures audio signals for input to the computing device. The computing equipment can process the current audio signal according to the steps So 1-So 2 to obtain the phase consistency parameter.

In an embodiment, to facilitate performance testing of a microphone array and improve testing efficiency, on the basis of any of the foregoing embodiments, before processing the audio signal, the method further includes the following steps:

s102a, when a starting instruction is detected, displaying a human-computer interface; the human-computer interface at least displays the single-channel specified parameter name, the inter-channel specified parameter name, a plurality of selection controls in one-to-one correspondence with the parameter names and a parameter calculation control;

and S102b, when receiving the instruction generated by triggering the parameter calculation control, determining the parameters required to be calculated currently according to the triggered selection control.

In an embodiment, the method of the present disclosure may be applied to application software to implement processing of signals collected by a microphone array and output a performance test result. Then in step S102a, when the application software is started, the application software detects a start instruction.

Alternatively, as shown in fig. 4, fig. 4 is a schematic diagram of a human-machine interface of application software for testing the performance of a microphone array, shown in the present disclosure according to an exemplary embodiment, and in addition to the contents configured in step S102a, a browsing control G for selecting an audio signal collected by the microphone array and a cutting control H for cutting the currently selected audio signal may be configured on the human-machine interface; therefore, the audio signals collected by the microphone array can be selected as the calculation basis of the currently selected parameters through the browsing control G according to the needs. In addition, when the selected audio signal comprises various audio signals, automatic identification and segmentation of the signals can be realized through the cutting control H, so that multiple parameters can be acquired at one time. As shown in fig. 5, fig. 5 is an interface schematic diagram of an application interface for configuring an audio file, which pops up after a browsing control G is clicked according to an exemplary embodiment of the present disclosure. In an application interface for configuring an audio file, a selection control of multiple test signals required in the present disclosure may be configured, as shown in fig. 5, a plurality of browsing controls corresponding to the multiple test signals one to one are configured, so that multiple audio signals may be input at one time, and the test efficiency is further improved.

Through steps S102a and S102b, the tester can select the parameters of the current required test as required, for example, when part of the parameters of the microphone array are known and no repeated test is needed, only the currently required parameters can be selected through the human-machine interface to avoid repeated parameter calculation and reduce the amount of parameter calculation, and accordingly, after step S102b, step S102c can be included: and processing the currently input audio signal according to the currently required calculated parameters to obtain the currently required calculated parameters.

Therefore, according to the method and the device, through the application software of the test method of the microphone array, the fact that personnel who do not know signal processing and acoustic knowledge can complete performance test of the microphone array through the application software is achieved, and therefore the threshold of the performance test of the microphone array, the test difficulty and the array parameter extraction difficulty are reduced. Moreover, the tester can obtain the parameter result only by carrying out the selection operation of the audio signal collected by the microphone array, the selection operation of the parameter to be calculated and the clicking operation of the parameter calculation control, thereby further improving the test efficiency and simplifying the test operation.

Corresponding to the foregoing embodiment of the testing method for a microphone array, as shown in fig. 6, fig. 6 is a block diagram illustrating a testing apparatus for a microphone array according to an exemplary embodiment of the present disclosure, and the present disclosure further provides a testing apparatus 30 for a microphone array, applied to a terminal, including:

a receiving module 31 configured to: receiving an audio signal obtained by collecting a test audio by a microphone array;

a processing module 32 configured to: processing the audio signals to obtain single-channel designated parameters of the microphones and inter-channel designated parameters between the microphones;

an output module 33 configured to: and determining the performance of the microphone array according to the single-channel specified parameters and the inter-channel specified parameters, and outputting a performance test result.

As shown in fig. 7, fig. 7 is a block diagram of a testing apparatus of a microphone array according to an exemplary embodiment of the present disclosure, and the processing module 32 includes at least one of: a sensitivity curve obtaining module 321, a total harmonic distortion curve generating module 322, a noise level obtaining module 323, a signal-to-noise ratio calculating module 324, a frequency response tolerance obtaining module 325, an external sealing property parameter obtaining module 326, a time delay consistency obtaining module 327, a correlation obtaining module 328, and an amplitude cut parameter obtaining module 329.

Optionally, the sensitivity curve acquiring module 321 includes:

a sensitivity level acquisition sub-module configured to: when the test audio frequency is 1kHz, the sound pressure level is sequentially reduced from 0dB to a preset sound pressure level by taking-2 dB as a tolerance, and the interruption time between every two adjacent groups of signals is a preset value, calculating the sensitivity level of each microphone on each single-frequency sinusoidal signal;

a sensitivity level curve acquisition sub-module configured to: and respectively generating a curve of the sensitivity level changing along with the sound pressure level according to the sensitivity level of each microphone in each single-frequency sinusoidal signal to obtain the sensitivity level curve of each microphone.

Optionally, the total harmonic distortion curve generation module 322 is configured to: when the test audio is a single-frequency sinusoidal signal sequence with 1kHz, the sound pressure level is sequentially reduced from 0dB to a preset sound pressure level by taking-2 dB as a tolerance, and the break time between every two adjacent groups of signals is a preset value, calculating the total harmonic distortion parameter of the audio signal at each sound pressure level according to the audio signal collected by the microphone array, and generating a total harmonic distortion curve.

Optionally, the noise level obtaining module 323 includes:

a voltage total energy acquisition submodule configured to: when the test audio is a mute signal or the test audio is paused to be played, acquiring the total voltage energy of the noise signals collected by each microphone;

a noise level calculation sub-module configured to: and respectively calculating the total energy of the full frequency band of each microphone based on the total energy of each voltage, wherein the total energy of the full frequency band is the noise level.

Optionally, the signal-to-noise ratio calculation module 324 is configured to: and calculating the difference between the sensitivity level of each microphone and the noise level of each microphone to obtain the signal-to-noise ratio of each microphone.

Optionally, the frequency response tolerance obtaining module 325 includes:

a frequency response curve generation submodule configured to: when the test audio is a logarithmic sweep frequency signal of 20 Hz-20 kHz and 0dB, generating a frequency response curve according to the audio signals collected by each microphone;

a frequency response tolerance calculation sub-module configured to: and calculating the difference between the maximum value and the minimum value of each frequency response curve to obtain the tolerance of the frequency response of each microphone.

Optionally, the external sealing performance parameter obtaining module 326 includes:

an energy calculation submodule configured to: when the test audio is a white noise signal of 0dB, calculating first single-frequency point energy of each frequency point of the audio signal acquired by each microphone when the sound receiving hole is not sealed, and calculating second single-frequency point energy of each frequency point of the audio signal acquired by each microphone when the sound receiving hole is sealed;

an energy difference mean calculation submodule configured to: and calculating to obtain the single-frequency point energy difference mean value of each microphone based on the first single-frequency point energy and the second single-frequency point energy, wherein the single-frequency point energy difference mean value is the external sealing parameter in the sealing parameters.

Optionally, the delay consistency obtaining module 327 includes:

a delay difference calculation sub-module configured to: when the test audio is a white noise signal of 0dB, calculating the time delay difference between the audio signals collected by every two microphones according to the audio signals collected by all the microphones;

a delay consistency parameter calculation submodule configured to: and calculating the average value of all the time delay differences to obtain the time delay consistency parameters of the microphone array.

Optionally, the correlation obtaining module 328 includes:

a correlation coefficient calculation sub-module configured to; when the test audio is a white noise signal of 0dB, calculating a correlation coefficient between audio signals acquired by every two microphones according to the audio signals acquired by each microphone;

a correlation parameter calculation sub-module configured to: and calculating the average value of all correlation coefficients to obtain the correlation parameters of the microphone array.

Optionally, the cropping parameter obtaining module 329 includes:

a waveform diagram generation submodule configured to: when the test audio is a white noise signal sequence which is changed from a 0dB white noise signal lasting for a preset time to a white noise signal sequence of which the sound pressure level is gradually reduced from 120dB by taking-3 dB as a tolerance, generating a signal waveform diagram according to the audio signals collected by the microphones;

an amplitude clipping parameter acquisition sub-module configured to: and determining the sound pressure level when the amplitude of the audio signal collected by each microphone is intercepted according to each signal oscillogram to obtain the amplitude interception parameter.

In an embodiment, the single channel specification parameters may further include: frequency band single frequency point energy mean. The processing module may further include:

a frequency band single frequency point energy mean value calculation module configured to: when the test audio is a mute signal or the test audio is paused to be played, dividing the working frequency band of each microphone into 3 continuous frequency bands, respectively calculating the energy average value of each frequency point of the noise signal collected by each microphone in each frequency band, and obtaining the frequency band single frequency point energy average value of each frequency band of each microphone.

In an embodiment, the processing module further includes a frequency response consistency obtaining module.

Optionally, the frequency response consistency obtaining module includes:

an inter-channel frequency response mean calculation sub-module configured to: calculating the average value of all frequency responses corresponding to each frequency point according to all frequency response curves to obtain the multichannel frequency response average value of each frequency point;

a frequency response consistency parameter acquisition sub-module configured to: calculating the difference between the frequency response of each frequency point of each frequency response curve and the corresponding multichannel frequency response mean value to obtain the mean value error of the frequency response of each frequency point of each frequency response curve, and generating the curve of the mean value error of the frequency response of each microphone along with the change of frequency into the same image to obtain a frequency response consistency curve among channels; and the inter-channel frequency response consistency curve is a frequency response consistency parameter.

In another embodiment, as another implementation of the frequency response consistency obtaining module, the frequency response consistency obtaining module includes:

a frequency response mean error modulus value calculation sub-module configured to: calculating the absolute value of the difference between the frequency response of each frequency point of each frequency response curve and the average value of the corresponding multi-channel frequency response to obtain the module value of the average value error of the frequency response of each frequency point of each frequency response curve;

a single frequency point module value mean value calculation submodule configured to: calculating the average value of all the modulus values corresponding to each frequency point to obtain the modulus value average value of each frequency point;

a frequency response consistency parameter calculation sub-module configured to: dividing all frequency points into 3 continuous frequency bands in sequence according to the magnitude order, and respectively calculating the quotient of the sum of all module value means of each frequency band and the bandwidth of the frequency band to obtain the frequency response module means of each frequency band; and the frequency response mode mean value is a frequency response consistency parameter.

In an embodiment, the apparatus may further include a display module and a parameter determination module.

The display module configured to: when a starting instruction is detected, displaying a human-computer interface; the human-computer interface at least displays the single-channel specified parameter name, the inter-channel specified parameter name, a plurality of selection controls in one-to-one correspondence with the parameter names, and a parameter calculation control.

The parameter determination module configured to: when an instruction generated by triggering the parameter calculation control is received, determining the current parameter required to be calculated according to the triggered selection control, and sending the parameter to the processing module.

In an embodiment where the apparatus comprises a display module and a parameter determination module, the processing module further comprises:

a specified parameter calculation submodule configured to: and processing the audio signal according to the currently required calculated parameters sent by the parameter determination module to obtain and output the required parameters.

The implementation process of the functions and actions of each module in the above device is specifically described in the implementation process of the corresponding step in the above method, and is not described herein again.

Corresponding to the embodiment of the testing method of the microphone array, the present disclosure also provides a testing system of the microphone array, which includes a sound source device, a loudspeaker and a computing device. The audio playing interface of the sound source equipment is in signal connection with the audio receiving interface of the loudspeaker; the audio input interface of the computing equipment is in signal connection with the audio output interface of the microphone array to be tested, and the computing equipment comprises the testing device.

When the microphone array to be tested is tested, the pickup end of the microphone array to be tested is opposite to the pronunciation end of the loudspeaker, and the center of the pickup end and the pronunciation center of the loudspeaker are positioned on the same horizontal straight line.

In an embodiment, the system further comprises a support for supporting the array of microphones to be tested. When the microphone array to be tested is arranged on the supporting panel of the support, the pickup end of the microphone array protrudes towards the loudspeaker direction compared with the supporting panel.

Corresponding to the foregoing embodiments of the testing method for a microphone array, the present disclosure also provides an electronic device of a testing apparatus for a microphone array, the electronic device including:

a processor;

a memory for storing a computer program executable by the processor;

when the processor executes the program, the method for testing the microphone array includes the following steps:

As shown in fig. 8, fig. 8 is a block diagram illustrating an electronic device of a testing apparatus of a microphone array according to an exemplary embodiment of the present disclosure. The electronic device 500 may be a terminal device such as a computer, a mobile phone, a messaging device, a game console, a tablet device, etc.

Referring to fig. 8, electronic device 500 may include one or more of the following components: processing component 501, memory 502, power component 503, multimedia component 504, audio component 505, interface to input/output (I/O) 506, sensor component 507, and communication component 508.

The processing component 501 generally controls overall operations of the electronic device 500, such as operations associated with display, telephone calls, data communications, camera operations, and recording operations. The processing component 501 may include one or more processors 509 to execute instructions to perform all or a portion of the steps of the methods described above. Further, the processing component 501 may include one or more modules that facilitate interaction between the processing component 501 and other components. For example, the processing component 501 may include a multimedia module to facilitate interaction between the multimedia component 504 and the processing component 501.

The memory 502 is configured to store various types of data to support operations at the electronic device 500. Examples of such data include instructions for any application or method operating on the electronic device 500, contact data, phonebook data, messages, pictures, videos, and so forth. The memory 502 may be implemented by any type or combination of volatile or non-volatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks.

The power supply component 503 provides power to the various components of the electronic device 500. The power components 503 may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power for the electronic device 500.

The multimedia component 504 includes a screen that provides an output interface between the electronic device 500 and a user. The screen may include a Touch Panel (TP), implemented as a touch screen, to receive an input signal from a user. The touch panel includes one or more touch sensors to sense touch, slide, and gestures on the touch panel. The touch sensor may not only sense the boundary of a touch or slide action, but also detect the duration and pressure associated with the touch or slide operation. In some embodiments, the multimedia component 504 includes a front facing camera and/or a rear facing camera. The front camera and/or the rear camera may receive external multimedia data when the electronic device 500 is in an operating mode, such as a shooting mode or a video mode. Each front camera and rear camera may be a fixed optical lens system or have a focal length and optical zoom capability.

The audio component 505 is configured to output and/or input audio signals. For example, the audio component 505 may include a Microphone (MIC) configured to receive external audio signals when the electronic device 500 is in an operational mode, such as a call mode, a recording mode, and a voice recognition mode. The received audio signals may further be stored in the memory 502 or transmitted via the communication component 508. In some embodiments, audio component 505 further comprises a speaker for outputting audio signals.

The I/O interface 502 provides an interface between the processing component 501 and peripheral interface modules, which may be keyboards, click wheels, buttons, etc. These buttons may include, but are not limited to: a home button, a volume button, a start button, and a lock button.

The sensor assembly 507 includes one or more sensors for providing various aspects of status assessment for the electronic device 500. For example, the sensor assembly 507 may detect an open/closed state of the electronic device 500, the relative positioning of components, such as a display and keypad of the electronic device 500, the sensor assembly 507 may also detect a change in the position of the electronic device 500 or a component of the electronic device 500, the presence or absence of user contact with the electronic device 500, orientation or acceleration/deceleration of the electronic device 500, and a change in the temperature of the electronic device 500. The sensor assembly 507 may include a proximity sensor configured to detect the presence of a nearby object without any physical contact. The sensor assembly 507 may also include a light sensor, such as a CMOS or CCD image sensor, for use in imaging applications. In some embodiments, the sensor assembly 507 may also include an acceleration sensor, a gyroscope sensor, a magnetic sensor, a pressure sensor, a temperature sensor, a photoelectric sensor, or a GPS sensor.

The communication component 508 is configured to facilitate wired or wireless communication between the electronic device 500 and other devices. The electronic device 500 may access a wireless network based on a communication standard, such as WiFi, 2G, 3G, or 4G, or a combination thereof. In an exemplary embodiment, the communication component 508 receives a broadcast signal or broadcast related information from an external broadcast management system via a broadcast channel. In an exemplary embodiment, the communication component 508 further includes a Near Field Communication (NFC) module to facilitate short-range communications. For example, the NFC module may be implemented based on Radio Frequency Identification (RFID) technology, infrared data association (IrDA) technology, Ultra Wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

In an exemplary embodiment, the electronic device 500 may be implemented by one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), controllers, micro-controllers, microprocessors or other electronic components for performing the above-described methods.

The implementation process of the functions and actions of each unit in the electronic device is specifically described in the implementation process of the corresponding step in the method, and is not described herein again.

For the device embodiments, since they substantially correspond to the method embodiments, reference may be made to the partial description of the method embodiments for relevant points. The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the disclosed solution. One of ordinary skill in the art can understand and implement it without inventive effort.

Corresponding to the aforementioned embodiments of the testing method of the microphone array, the present disclosure also provides a computer-readable storage medium, on which a computer program is stored, which when executed by the processor 509 of the electronic device realizes the steps of the testing method of the microphone array, including: receiving an audio signal obtained by collecting a test audio by a microphone array;

The present disclosure may take the form of a computer program product embodied on one or more storage media including, but not limited to, disk storage, CD-ROM, optical storage, and the like, having program code embodied therein. Computer-usable storage media include permanent and non-permanent, removable and non-removable media, and information storage may be implemented by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of the storage medium of the computer 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 technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic tape disk storage or other magnetic storage devices, or any other non-transmission medium may be used to store information that may be accessed by a computing device.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

The above description is only exemplary of the present disclosure and should not be taken as limiting the disclosure, as any modification, equivalent replacement, or improvement made within the spirit and principle of the present disclosure should be included in the scope of the present disclosure.

Claims

1. A method for testing a microphone array, the method comprising:

wherein the single channel specification parameters include: sensitivity level, sensitivity level curve, noise level, total harmonic distortion parameter, total harmonic distortion curve, signal-to-noise ratio, tolerance of frequency response, tightness parameter and clipping parameter; the inter-channel specifying parameters include: frequency response consistency parameters, time delay consistency parameters and correlation parameters;

wherein, the processing the audio signal to obtain the single-channel specific parameters of each microphone and the inter-channel specific parameters between the microphones includes:

when the test audio is a logarithmic sweep frequency signal of 20 Hz-20 kHz and 0dB, generating a frequency response curve according to the audio signals collected by each microphone; calculating the average value of all frequency responses corresponding to each frequency point according to all frequency response curves to obtain the multichannel frequency response average value of each frequency point;

calculating the difference between the frequency response of each frequency point of each frequency response curve and the corresponding multichannel frequency response mean value to obtain the mean value error of the frequency response of each frequency point of each frequency response curve, and generating the curve of the mean value error of the frequency response of each microphone along with the change of frequency into the same image to obtain a frequency response consistency curve among channels; the inter-channel frequency response consistency curve is a frequency response consistency parameter;

alternatively, the first and second electrodes may be,

calculating the absolute value of the difference between the frequency response of each frequency point of each frequency response curve and the average value of the corresponding multi-channel frequency response to obtain the module value of the average value error of the frequency response of each frequency point of each frequency response curve;

calculating the average value of all the modulus values corresponding to each frequency point to obtain the modulus value average value of each frequency point;

dividing all frequency points into 3 continuous frequency bands in sequence according to the magnitude order, and respectively calculating the quotient of the sum of all module value means of each frequency band and the bandwidth of the frequency band to obtain the frequency response module means of each frequency band; and the frequency response mode mean value is a frequency response consistency parameter.

2. The method of claim 1, wherein the pickup end of the microphone array is opposite to the sound emitting end of the speaker, and the center of the pickup end is on the same horizontal straight line with the sound emitting center of the speaker;

the test audio is played by the pronunciation end of the loudspeaker and is collected by the pickup end of the microphone array.

3. The method of claim 1, wherein the step of processing the audio signal to obtain the single-channel specific parameters of each microphone and the inter-channel specific parameters between microphones comprises at least one of:

when the test audio frequency is 1kHz, the sound pressure level is sequentially reduced from 0dB to a preset sound pressure level by taking-2 dB as a tolerance, and the interruption time between every two adjacent groups of signals is a preset value, calculating the sensitivity level of each microphone on each single-frequency sinusoidal signal; respectively generating a curve of which the sensitivity level changes along with the sound pressure level according to the sensitivity level of each microphone on each single-frequency sinusoidal signal to obtain a sensitivity level curve of each microphone;

when the test audio is a mute signal or the test audio is paused to be played, acquiring the total voltage energy of the noise signals collected by each microphone; respectively calculating the total energy of the full frequency band of each microphone based on the total energy of each voltage, wherein the total energy of the full frequency band is the noise level;

calculating the difference between the sensitivity level of each microphone and the noise level thereof to obtain the signal-to-noise ratio of each microphone;

when the test audio is a logarithmic sweep frequency signal of 20 Hz-20 kHz and 0dB, generating a frequency response curve according to the audio signals collected by each microphone; calculating the difference between the maximum value and the minimum value of each frequency response curve to obtain the tolerance of the frequency response of each microphone;

when the test audio is a white noise signal of 0dB, calculating first single-frequency point energy of each frequency point of the audio signal acquired by each microphone when the sound receiving hole is not sealed, and calculating second single-frequency point energy of each frequency point of the audio signal acquired by each microphone when the sound receiving hole is sealed; calculating to obtain a single-frequency point energy difference mean value of each microphone based on the first single-frequency point energy and the second single-frequency point energy, wherein the single-frequency point energy difference mean value is an external sealing parameter in the sealing parameters;

when the test audio is a white noise signal of 0dB, calculating the time delay difference between the audio signals collected by every two microphones according to the audio signals collected by all the microphones; calculating the average value of all time delay differences to obtain time delay consistency parameters of the microphone array;

when the test audio is a white noise signal sequence which is changed from a 0dB white noise signal lasting for a preset time to a white noise signal sequence of which the sound pressure level is gradually reduced from 120dB by taking-3 dB as a tolerance, generating a signal waveform diagram according to the audio signals collected by the microphones; and determining the sound pressure level when the amplitude of the audio signal collected by each microphone is intercepted according to each signal oscillogram to obtain the amplitude interception parameter.

4. The method of claim 3, wherein the single channel specification parameters further comprise: the average value of the energy of the single frequency point of the frequency band;

when the test audio is a mute signal or the playing of the test audio is suspended, the method further comprises:

the working frequency band of each microphone is divided into 3 continuous frequency bands, the energy average value of each frequency point of the noise signal collected by each microphone in each frequency band is calculated respectively, and the frequency band single-frequency-point energy average value of each frequency band of each microphone is obtained.

5. The method of claim 1, wherein prior to processing the audio signal, further comprising:

when a starting instruction is detected, displaying a human-computer interface; the human-computer interface at least displays the single-channel specified parameter name, the inter-channel specified parameter name, a plurality of selection controls in one-to-one correspondence with the parameter names and a parameter calculation control;

when an instruction generated by triggering the parameter calculation control is received, determining the current parameter required to be calculated according to the triggered selection control.

6. A test apparatus for a microphone array, comprising:

wherein the single channel specification parameters include: sensitivity level, sensitivity level curve, total harmonic distortion parameter, total harmonic distortion curve, noise level, signal-to-noise ratio, tolerance of frequency response, tightness parameter and clipping parameter; the inter-channel specifying parameters include: frequency response consistency parameters, time delay consistency parameters and correlation parameters;

the processing module comprises a frequency response consistency acquiring module;

the frequency response consistency acquisition module comprises:

an inter-channel frequency response mean calculation sub-module configured to: when the test audio is a logarithmic sweep frequency signal of 20 Hz-20 kHz and 0dB, generating a frequency response curve according to the audio signals collected by each microphone; calculating the average value of all frequency responses corresponding to each frequency point according to all frequency response curves to obtain the multichannel frequency response average value of each frequency point;

a frequency response consistency parameter acquisition sub-module configured to: calculating the difference between the frequency response of each frequency point of each frequency response curve and the corresponding multichannel frequency response mean value to obtain the mean value error of the frequency response of each frequency point of each frequency response curve, and generating the curve of the mean value error of the frequency response of each microphone along with the change of frequency into the same image to obtain a frequency response consistency curve among channels; the inter-channel frequency response consistency curve is a frequency response consistency parameter;

or, the frequency response consistency obtaining module includes:

7. The apparatus of claim 6, wherein the processing module comprises at least one of: the device comprises a sensitivity curve acquisition module, a noise level acquisition module, a signal-to-noise ratio calculation module, a frequency response tolerance acquisition module, an external sealing property parameter acquisition module, a time delay consistency acquisition module and an amplitude cut parameter acquisition module;

the sensitivity curve acquisition module includes:

a sensitivity level curve acquisition sub-module configured to: respectively generating a curve of which the sensitivity level changes along with the sound pressure level according to the sensitivity level of each microphone on each single-frequency sinusoidal signal to obtain a sensitivity level curve of each microphone;

the noise level acquisition module includes:

a noise level calculation sub-module configured to: respectively calculating the total energy of the full frequency band of each microphone based on the total energy of each voltage, wherein the total energy of the full frequency band is the noise level;

the signal-to-noise ratio calculation module is configured to: calculating the difference between the sensitivity level of each microphone and the noise level thereof to obtain the signal-to-noise ratio of each microphone;

the frequency response tolerance acquisition module comprises:

a frequency response tolerance calculation sub-module configured to: calculating the difference between the maximum value and the minimum value of each frequency response curve to obtain the tolerance of the frequency response of each microphone;

the external sealability parameter acquisition module comprises:

an energy difference mean calculation submodule configured to: calculating to obtain a single-frequency point energy difference mean value of each microphone based on the first single-frequency point energy and the second single-frequency point energy, wherein the single-frequency point energy difference mean value is an external sealing parameter in the sealing parameters;

the time delay consistency obtaining module comprises:

a delay consistency parameter calculation submodule configured to: calculating the average value of all time delay differences to obtain time delay consistency parameters of the microphone array;

the cropping parameter acquisition module comprises:

8. The apparatus of claim 7, wherein the single channel specification parameters further comprise: the average value of the energy of the single frequency point of the frequency band;

the processing module further comprises:

9. The apparatus of claim 6, further comprising a display module and a parameter determination module:

the display module configured to: when a starting instruction is detected, displaying a human-computer interface; the human-computer interface at least displays the single-channel specified parameter name, the inter-channel specified parameter name, a plurality of selection controls in one-to-one correspondence with the parameter names and a parameter calculation control;

the parameter determination module configured to: when an instruction generated by triggering a parameter calculation control is received, determining the current parameter required to be calculated according to the triggered selection control, and sending the parameter to the processing module;

the processing module comprises:

10. A test system of a microphone array is characterized by comprising a sound source device, a loudspeaker and a computing device; the audio playing interface of the sound source equipment is in signal connection with the audio receiving interface of the loudspeaker; the audio input interface of the computing equipment is in signal connection with the audio output interface of the microphone array to be tested, and the computing equipment comprises the device of any one of claims 6-9;

11. The system of claim 10, further comprising a support for supporting the array of microphones under test;

when the microphone array to be tested is arranged on the supporting panel of the support, the pickup end of the microphone array protrudes towards the loudspeaker direction compared with the supporting panel.

12. An electronic device, comprising:

a processor;

a memory for storing a computer program executable by the processor;

wherein the processor implements the steps of the method of any one of claims 1 to 5 when executing the program.

13. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 5.