Earphone noise suppression test system, method, device and computer readable storage medium

Abstract

This invention discloses a headphone noise suppression testing system, method, device, and computer-readable storage medium. The system includes a simulated human head model, a sound source array, and a control and processing unit. The simulated human head model is equipped with a simulated human ear for housing a reference microphone and the headphone under test. The sound source array surrounds the simulated human head model and can emit test signals from multiple directions. The control and processing unit controls the sound source array to emit test signals, simultaneously acquiring a reference audio signal from the reference microphone within the simulated human head's ear canal and a noise-reduced frequency signal acquired by the headphone under test. The noise suppression level is calculated based on the reference audio signal and the noise-reduced frequency signal. Then, based on the noise suppression levels corresponding to at least two test signals from different directions, the uniformity of the headphone's noise reduction performance in each direction is determined. This system detects the noise reduction performance of the headphone under test from different directions using multi-directional test signals, enabling a more comprehensive and objective test of the headphone's noise reduction performance.

Description

Technical Field

[0001] This invention relates to the field of headphone testing technology, and in particular to a headphone noise suppression testing system, method, apparatus, and computer-readable storage medium. Background Technology

[0002] With the widespread use of remote conferencing platforms in the workplace, the requirements for noise-canceling headphones in meetings are becoming increasingly stringent. Evaluations of indicators such as call clarity, noise reduction effect, echo cancellation performance, background noise level, and voice quality are becoming more standardized and objective. To ensure clear meeting audio, accurate testing of the noise suppression capabilities of noise-canceling headphones has become a crucial technical aspect. Currently, the industry typically uses subjective listening tests with people wearing the headphones in noisy environments, or objective tests using a simple single sound source in a specific direction. While these methods can reflect the noise reduction performance of headphones to some extent, they suffer from problems such as uncontrollable testing environments, highly subjective test results, and poor repeatability. In particular, existing testing schemes lack simulation of multi-directional and multi-angle noise sources, making it difficult to comprehensively evaluate the performance of headphones in real-world complex sound fields, leading to significant discrepancies between test results and actual usage scenarios.

[0003] To address the problems of uncontrollable environment, incomplete testing, and inaccurate results in existing noise suppression testing methods for noise-canceling headphones, this application proposes a systematic simulation testing scheme aimed at achieving an objective, comprehensive, and repeatable evaluation of the noise reduction performance of noise-canceling headphones. Summary of the Invention

[0004] The purpose of this invention is to provide a headphone noise suppression testing system, method, device, and computer-readable storage medium, aiming to solve the problem that headphone noise suppression testing is not comprehensive enough in the prior art.

[0005] To address the aforementioned technical problems, the first aspect of this application provides a headphone noise suppression testing system. The system includes: a simulated human head model with a simulated human ear for housing a reference microphone and a headphone under test; a sound source array surrounding the simulated human head model for emitting test signals in different directions to the simulated human head model; and a control processing unit connected to the sound source array, the reference microphone, and the headphone under test, for controlling the sound source array to emit test signals, acquiring a reference audio signal obtained by the reference microphone within the ear canal of the simulated human head model from the test signals, and simultaneously acquiring a noise-reduced frequency signal obtained by the headphone under test worn by the simulated human head model from the test signals; the control processing unit is further configured to determine a noise suppression amount based on the reference audio signal and the noise-reduced frequency signal, and to determine the uniformity of noise reduction performance of the headphone under test in different directions based on at least two noise suppression amounts corresponding to at least two test signals emitted by the sound source array in at least two different directions.

[0006] In one embodiment, the control processing unit is further configured to: obtain the noise suppression amount in the corresponding direction by logarithmic operation based on the energy ratio of the sum of signal energy of the reference audio signal to the sum of signal energy of the noise-reduced frequency signal.

[0007] In one embodiment, the control processing unit is further configured to: perform an arithmetic mean operation on the at least two noise suppression quantities to obtain an average noise suppression quantity of the earphone under test; calculate a standard deviation based on the deviation of each noise suppression quantity from the average noise suppression quantity; and obtain the uniformity of the noise reduction performance through a normalization operation based on the ratio of the standard deviation to the average noise suppression quantity.

[0008] In one embodiment, the sound source array consists of a set number of loudspeakers, which are evenly distributed on a horizontal circle or a three-dimensional sphere centered on the simulated human head model.

[0009] In one embodiment, the number of loudspeakers is at least four, and the angle between the lines connecting adjacent loudspeakers and the simulated human head model is in the range of 40° to 90°.

[0010] In one embodiment, if the loudspeakers are evenly distributed on a three-dimensional sphere with the simulated human head model as the center, at least two loudspeakers are distributed above the horizontal plane where the simulated human head model is located, and at least two loudspeakers are distributed below the horizontal plane where the simulated human head model is located.

[0011] In one embodiment, the number of speakers is at least six. The speakers located above the horizontal plane where the simulated human head model is located have a pitch angle of 30° to 60° relative to the simulated human head model, while the speakers located below the horizontal plane where the simulated human head model is located have a pitch angle of -60° to -30° relative to the simulated human head model.

[0012] To address the aforementioned technical problems, a second aspect of this application provides a headphone noise suppression testing method, applied to the testing system provided in the first aspect. The method includes: controlling the sound source array to emit a test signal; acquiring a reference audio signal obtained by a reference microphone inside the ear canal of the simulated human head model collecting the test signal, and simultaneously acquiring a noise-reduced frequency signal obtained by the headphone under test worn by the simulated human head model collecting the test signal; determining a noise suppression amount based on the reference audio signal and the noise-reduced frequency signal; and determining the uniformity of noise reduction performance of the headphone under test in different directions based on at least two noise suppression amounts corresponding to at least two test signals emitted by the sound source array in at least two different directions.

[0013] To address the aforementioned technical problems, a third aspect of this application provides a headphone noise suppression testing device, comprising a processor and a memory coupled to each other; the memory stores a computer program, and the processor executes the computer program to implement the steps of the method provided in the second aspect above.

[0014] To address the aforementioned technical problems, a fourth aspect of this application provides a computer-readable storage medium storing program data, which, when executed by a processor, implements the steps of the method provided in the second aspect above.

[0015] The present invention provides the following advantages: Unlike existing technologies, the headphone noise suppression testing system utilizes: a simulated human head model with a simulated ear for housing a reference microphone and the headphone under test; a sound source array surrounding the simulated human head model to emit test signals from different directions; and a control processing unit connected to the sound source array, the reference microphone, and the headphone under test. This unit controls the sound source array to emit test signals and acquires a reference audio signal obtained by the reference microphone within the ear canal of the simulated human head model, simultaneously acquiring a noise-reduced frequency signal obtained by the headphone under test wearing the simulated human head model. The control processing unit further determines the noise suppression level based on the reference audio signal and the noise-reduced frequency signal, and determines the uniformity of noise reduction performance of the headphone under test in different directions based on at least two noise suppression levels corresponding to at least two test signals emitted by the sound source array from at least two different directions. Through this method, the noise reduction performance of the headphone under test can be detected from different locations based on multi-directional test signals, enabling a more comprehensive and objective test of headphone noise reduction performance. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] in: Figure 1 This is a schematic diagram of an embodiment of the headphone noise suppression testing system of this application; Figure 2 This is a schematic diagram of an embodiment of the sound source array arrangement of this application; Figure 3 This is a schematic flowchart of an embodiment of the headphone noise suppression test method of this application; Figure 4 This is a flowchart illustrating an embodiment of step S14 of this application, which determines the uniformity of noise reduction performance of the headphones under test. Figure 5 This is a schematic block diagram of an embodiment of the headphone noise suppression testing device of this application; Figure 6 This is a schematic block diagram of an embodiment of a computer-readable storage medium of this application. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The terms "first" and "second" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.

[0020] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0021] Please see Figure 1 , Figure 1 This is a schematic diagram of an embodiment of the headphone noise suppression test system of this application. The headphone noise suppression test system includes: a simulated human head model 110, a sound source array 120, and a control processing unit 130.

[0022] The simulated human head model 110 is equipped with a simulated human ear for housing a reference microphone and a test earphone. A sound source array 120 is arranged around the simulated human head model 110 to emit signals in different directions. A control processing unit 130 is connected to the sound source array 120, the reference microphone (not shown), and the test earphone (not shown). It controls the sound source array 120 to emit test signals and acquires a reference audio signal obtained by the reference microphone within the ear canal of the simulated human head model 110, while simultaneously acquiring a noise-reduced frequency signal obtained by the test earphone worn by the simulated human head model 110. The control processing unit 130 further determines the noise suppression level based on the reference audio signal and the noise-reduced frequency signal, and determines the uniformity of the noise reduction performance of the test earphone in different directions based on at least two noise suppression levels corresponding to at least two test signals emitted by the sound source array 120 in at least two different directions.

[0023] The simulated human head model 110 and the sound source array 120 are arranged inside a dedicated acoustic testing anechoic chamber. This anechoic chamber can be configured as a semi-anechoic chamber or a fully anechoic chamber depending on the required testing accuracy. The inner walls of the anechoic chamber are lined with high-performance sound-absorbing materials, which efficiently absorb incident sound waves, significantly reducing multiple reflections and reverberation within the space. Simultaneously, the sealed sound insulation structure blocks external environmental noise, equipment operating noise, and structural vibration interference, thus creating an ideal acoustic testing environment with extremely low background noise, a near-free-field sound field, and no significant sound reflections. Conducting headphone noise reduction performance tests in this environment minimizes the influence of non-test factors such as environmental reflections, external noise, and uneven sound field. This ensures that the acquired reference audio signal and noise-reduced frequency signal accurately reflect the acoustic characteristics and noise reduction effect of the headphone under test, effectively improving the accuracy and consistency of the test data and guaranteeing good objectivity, stability, and repeatability of the test results.

[0024] The simulated human head model 110, due to its shape, size and acoustic characteristics simulating a real human body, is used to standardize the wearing of the headphones under test. A reference microphone can be set in the ear canal to accurately collect the original sound field signal that has not been processed by the headphones under test, as a benchmark reference for evaluating the noise suppression processing effect of the headphones under test.

[0025] The control processing unit 130 implements independent gain control, delay control, and filtering for each speaker in the sound source array 120, ensuring that the sound source array can synthesize a composite noise field that meets the test requirements. This provides a realistic and controllable noise environment for headphone noise reduction performance testing, enabling the sound source array 120 to synthesize a composite noise field with specific directionality, multi-angle, and multi-spectral characteristics. It can flexibly simulate complex noise environments from different directions, heights, and types in the real world (such as traffic noise existing at multiple angles simultaneously, and human voice interference from multiple directions). This allows for a more comprehensive and realistic test of the noise reduction performance of the headphones under test in different noise scenarios, further improving the comprehensiveness and accuracy of headphone noise reduction testing.

[0026] In terms of gain control, the control processing unit 130 is equipped with an independent digital gain adjustment module for each speaker. The adjustment range can be flexibly set according to the test scenario (typically -60dB to +12dB), supporting high-precision adjustment at the 0.1dB level. Through independent gain control, it can compensate for the sensitivity differences of different speakers, the sound pressure attenuation caused by the installation position, and the energy loss during sound wave propagation. This ensures that the sound pressure level remains consistent when the test signal emitted by each speaker reaches the reference point of the simulated human head model 110, avoiding sound field distortion caused by individual speaker differences and providing a uniform sound field environment for subsequent noise reduction performance testing.

[0027] Regarding delay control, firstly, the control processing unit 130 pre-stores the installation coordinates of each speaker in the sound source array 120, as well as the coordinates of the reference point of the simulated human head model 110 (e.g., the midpoint of the line connecting the two ears of the simulated human head model 110). It then automatically calculates the straight-line distance dn from each speaker to the reference point using a spatial distance algorithm. Subsequently, it combines the real-time sound velocity c under the test environment (which can be dynamically calibrated using temperature and humidity sensor data in the anechoic chamber to avoid the influence of environmental factors on the sound velocity) and calculates the delay amount τn of each speaker according to the formula τn=dn / c. Finally, the control processing unit sends the delay amount to the corresponding speaker's driver module, controlling the speaker to emit sound according to the set delay time, ensuring that sound waves emitted from speakers at different locations and heights can arrive at the reference point of the simulated human head model 110 synchronously in a preset timing sequence, eliminating timing deviations caused by differences in propagation distance.

[0028] In terms of filtering, the control processing unit 130 is equipped with an independent digital filtering module for each speaker, supporting multiple filtering modes such as high-pass, low-pass, band-pass, and notch filtering. Filtering parameters (including cutoff frequency, filter slope, and quality factor) can be flexibly configured according to testing requirements. The core function of filtering is to perform spectrum shaping on the test signal. On the one hand, it filters out high-frequency noise and low-frequency interference from the test signal, ensuring the spectral purity of the test signal. On the other hand, it can perform targeted filtering on the output signal of each speaker based on the spectral characteristics of real-world noise scenarios (such as traffic noise, office noise, and environmental noise), making the synthesized composite noise field more closely resemble the noise spectrum of the real world, thus improving the realism and relevance of the test.

[0029] The control processing unit 130 can establish independent communication links with the sound source array 120, the reference microphone, and the earphone under test, respectively. Connection methods include wired and wireless communication to balance signal stability and testing convenience. Specifically, the control processing unit 130 can use a wired communication connection with the sound source array 120 and the reference microphone inside the ear canal of the simulated human head model. Ethernet, USB high-speed transmission, or dedicated audio differential signal cables can be used to achieve low-latency, highly stable control command issuance and raw audio signal acquisition, avoiding interference and timing deviations. The control processing unit 130 can use a wireless communication connection with the earphone under test, supporting Bluetooth classic mode, BLE low-power Bluetooth, and Wi-Fi audio protocols, adapting to different earphone wireless transmission standards, and used to synchronously receive noise-reduced audio data transmitted from the earphone. Simultaneously, the control processing unit has a built-in timing calibration module that can automatically compensate for the latency differences between wired and wireless links, ensuring strict synchronization of multi-channel signals in the time domain, providing a reliable data foundation for subsequent noise reduction performance calculations.

[0030] In one embodiment, the sound source array 120 comprises a predetermined number of loudspeakers, which are evenly distributed on a horizontal circle centered on the simulated human head model 110. The number of loudspeakers is at least four, and the angle between the lines connecting adjacent loudspeakers and the simulated human head model is in the range of 40° to 90°. The radius of the horizontal circle centered on the simulated human head model 110 is in the range of 0.5 to 2 m, for example, 0.5 m, 1 m, or 2 m.

[0031] Please refer to Figure 2 , Figure 2This is a schematic diagram of an embodiment of the sound source array arrangement of this application. The number of loudspeakers is eight, and the azimuth angles of each loudspeaker relative to the simulated human head model 110 are: 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, respectively. For clarity, the above azimuth angles can be understood as follows: azimuth angle 0° indicates the loudspeaker is directly in front of the simulated human head model 110; azimuth angle 90° indicates the loudspeaker is directly to the right of the simulated human head model 110; azimuth angle 180° indicates the loudspeaker is directly behind the simulated human head model 110; azimuth angle 270° indicates the loudspeaker is directly to the left of the simulated human head model 110; and the remaining azimuth angles are distributed clockwise to achieve 360° omnidirectional uniform coverage. The number of loudspeakers can be expanded to 16, 32, etc., according to actual testing needs to achieve more refined azimuth coverage and more complex noise field synthesis.

[0032] Specifically, the speaker array in the sound source array 120 consists of eight full-range monitoring speakers, each with a frequency response range of 50Hz-20kHz (±2dB). The maximum sound pressure level at a radius of 1m around the speakers is 110dB. These speakers are evenly distributed around a simulated human head model 110 on a horizontal circle with a radius of 1m. The center height of the tweeters of all speakers is level with the entrance to the ear canal of the model, and the height of the speakers is, for example, 1.2m. This standardized configuration of eight speakers evenly distributed on a horizontal circle can comprehensively simulate noise sources from any direction in the horizontal plane, covering noise interference from key directions such as the front, sides, and rear, thereby improving the representativeness and realism of the test scenario, while controlling the complexity of the test system while ensuring sufficient spatial resolution. For example, when simulating an office environment, the system can use horizontal speakers (such as 90° or 270°) to simulate the sound of colleagues talking from the side, and use 180° speakers to simulate the noise of a printer at the back, thus simulating the acoustic environment of complex noise fields and pure voice signal scenarios, thereby comprehensively evaluating the noise reduction performance of the headphones in the horizontal direction.

[0033] In one embodiment, the sound source array 120 consists of a predetermined number of loudspeakers, which are evenly distributed on a three-dimensional sphere centered on the simulated human head model. Optionally, at least two of the loudspeakers are distributed above the horizontal plane where the simulated human head model 110 is located, and at least two of the loudspeakers are distributed below the horizontal plane where the simulated human head model 110 is located.

[0034] The system comprises at least six speakers. The speakers located above the horizontal plane of the simulated human head model have a pitch angle of 30° to 60° relative to the simulated human head model, while the speakers located below the horizontal plane of the simulated human head model have a pitch angle of -60° to -30° relative to the simulated human head model.

[0035] The radius of the three-dimensional sphere with the simulated human head model as its center is in the range of 0.8 to 2m, for example, 1m, 1.2m, 2m, etc.

[0036] Specifically, the number of loudspeakers can be eight, and the azimuth and elevation angles of each loudspeaker relative to the simulated human head model 110 are as follows: (azimuth 0°, elevation 0°), (azimuth 90°, elevation 0°), (azimuth 180°, elevation 0°), (azimuth 270°, elevation 0°), (azimuth 45°, elevation 45°), (azimuth 135°, elevation 45°), (azimuth 225°, elevation -45°), (azimuth 315°, elevation -45°). The number of loudspeakers can be expanded to 16, 32, etc., according to actual testing needs to achieve more precise azimuth coverage and more complex noise field synthesis. To clarify the azimuth definition, the positions of each loudspeaker relative to the simulated human head model 110 can be understood as follows: (Azimuth 0°, Pitch 0°) indicates that the speaker is located in the horizontal direction directly in front of the simulated human head model 110; (Azimuth 90°, Pitch 0°) indicates that the speaker is located in the horizontal direction directly to the right of the simulated human head model 110; (Azimuth 180°, Pitch 0°) indicates that the speaker is located horizontally directly behind the simulated human head model 110; (Azimuth 270°, Pitch 0°) indicates that the speaker is located in the horizontal direction directly to the left of the simulated human head model 110; (45° azimuth, 45° pitch) indicates that the speaker is located on the upper right front of the simulated human head model 110; (Azimuth 135°, Pitch 45°) indicates that the speaker is located on the upper right rear of the simulated human head model 110; (Azimuth 225°, Pitch -45°) indicates that the speaker is located at the lower left rear of the simulated human head model 110; (Azimuth 315°, Pitch -45°) indicates that the speaker is located at the lower left front of the simulated human head model 110.

[0037] In practical applications where speakers are distributed in a three-dimensional spherical pattern, the distance measurement accuracy from each speaker to the center of the head must reach ±1cm, and the azimuth and pitch angle installation accuracy must reach ±1°. This allows the sound source array 120 to more accurately simulate noise sources from different heights in a real environment, such as air conditioning vents on the ceiling or mechanical equipment on the ground. It extends the sound field synthesis from a two-dimensional horizontal plane to three-dimensional space, significantly improving the realism and complexity of the test scenario. This makes the evaluation of the headphone's noise reduction performance in real, complex three-dimensional noise environments more comprehensive and accurate.

[0038] For example, when simulating an office environment, the system can use a speaker with an azimuth angle of 45° and a pitch angle of 45° to simulate air conditioner noise from the upper right (set to bandpass noise with a center frequency of 500Hz and a sound pressure level of 55dB SPL), while using a speaker with an azimuth angle of 225° and a pitch angle of -45° to simulate computer fan noise from the lower left (set to bandpass noise with a center frequency of 800Hz and a sound pressure level of 50dB SPL), thereby creating a more realistic multi-layered noise environment and simulating various complex noise scenarios.

[0039] The control processing unit 130 can adopt a dual-core architecture with an embedded main control chip and an audio processing chip, respectively communicating with the sound source array 120, the reference microphone, and the earphone under test. It is also equipped with a high-precision clock synchronization module to ensure the consistency of the timing of multi-channel signal acquisition. It can independently configure the sound source array 120's emission frequency, sound pressure level, duration, and emission angle to achieve directional, time-division, or synchronous sound emission control, and supports switching between various test signal modes such as white noise signal, pink noise signal, traffic noise signal, and voice signal.

[0040] In the acquisition of the reference audio signal and the noise-reduced audio signal, the control processing unit 130 can acquire the original reference audio signal collected by the reference microphone inside the ear canal of the simulated human head model 110 in real time through the low-noise audio acquisition circuit, and simultaneously acquire the noise-reduced audio signal returned by the earphone under test, completing signal amplification, analog-to-digital conversion, and noise reduction filtering preprocessing. It also has a signal verification function, which can eliminate abnormal data and automatically reissue test commands to ensure the accuracy and effectiveness of the acquired data, providing reliable data for subsequent noise suppression calculation and noise reduction performance analysis.

[0041] The control processing unit 130 can specifically execute the following headphone noise suppression test method to test the noise reduction performance of the headphone under test. For details, please refer to the description of each embodiment of the headphone noise suppression test method below.

[0042] Please see Figure 3 , Figure 3This is a schematic flowchart of an embodiment of the headphone noise suppression test method of this application. It should be noted that if substantially the same result is obtained, this embodiment is not necessarily identical. Figure 3 The process sequence shown is limited. It includes the following steps S11~S14: S11: Control the sound source array to emit test signals.

[0043] Based on the direction of the noise to be tested, the system sequentially controls each speaker in the sound source array to emit test signals according to a preset control sequence. For example, to test the noise reduction performance of headphones in the directions of eight speakers, the system sequentially controls each speaker to emit a test signal.

[0044] In this process, the delay time for each speaker can be pre-determined based on the ratio of the distance from each speaker to the reference point of the simulated human head model 110 (e.g., the midpoint of the line connecting the two ears of the simulated human head model 110) and the real-time sound velocity c in the test environment. This delay time is then sent to the corresponding speaker's driver module. This step controls the speaker to emit test signals based on the delay time. This ensures that sound waves emitted from speakers at different locations and heights can arrive at the reference point of the simulated human head model 110 synchronously in a preset timing sequence, eliminating timing deviations caused by differences in propagation distance.

[0045] S12: Obtain the reference audio signal obtained by the reference microphone in the ear canal of the simulated human head model to collect the test signal, and simultaneously obtain the noise-reduced frequency signal obtained by the earphone worn by the simulated human head model to collect the test signal.

[0046] Based on the communication connection with the reference microphone and the earphone under test, a reference audio signal and a noise-reduced frequency signal are acquired from the reference microphone and the earphone under test. The reference audio signal can basically simulate the audio signal that the human ear can hear in a natural state without noise reduction processing; the noise-reduced frequency signal is the signal collected by the earphone under test after noise reduction of the test signal.

[0047] S13: Determine the noise suppression amount based on the reference audio signal and the noise-reduced frequency signal.

[0048] The noise suppression measure is a quantitative value used to characterize the noise suppression effect of the headphone under test on the test signal.

[0049] In one embodiment, the noise suppression amount is calculated as follows: based on the energy ratio of the sum of the signal energy of the reference audio signal to the sum of the signal energy of the noise-reduced frequency signal, the noise suppression amount in the corresponding direction is obtained through logarithmic calculation. Specifically, the noise suppression amount is calculated with reference to the following formula: in, Indicates the noise suppression level. This represents the total signal energy of the reference audio signal. This represents the total signal energy of the noise-reduced frequency signal.

[0050] S14: Determine the uniformity of noise reduction performance of the headphone under test in different directions based on at least two noise suppression quantities corresponding to at least two test signals emitted from at least two different directions by the sound source array.

[0051] This application controls the sound source array to emit test signals in at least two different directions, and controls the emission of a test signal in one direction at a time. Based on the test signal in that direction, the noise suppression amount corresponding to the test signal in that direction is calculated, thus obtaining the noise suppression amount in multiple directions.

[0052] In one embodiment, before step S13, the acquired reference audio signal and noise-reduced frequency signal are preprocessed. Specifically, the acquired original reference audio signal and original noise-reduced frequency signal are first subjected to DC offset removal, gain normalization, and bandpass filtering to eliminate circuit noise and ensure signal purity. Then, the processed reference audio signal and noise-reduced frequency signal are time-domain aligned. Specifically, the peak time delay of the reference audio signal and noise-reduced frequency signal can be detected by a cross-correlation algorithm, and the time offset introduced by Bluetooth wireless transmission, internal headphone processing, analog-to-digital conversion, etc. can be identified and compensated to achieve strict synchronization between the reference audio signal and the noise-reduced frequency signal at the sampling point level. This time-domain alignment process can dynamically adapt to different Bluetooth versions, transmission protocols, and headphone firmware delay differences, automatically correct sampling offsets and frame misalignments, and ensure that the subsequent noise suppression calculation is not affected by transmission delay, thereby improving the consistency and accuracy of noise reduction performance comparisons in different directions.

[0053] Please see Figure 4 , Figure 4 This is a schematic flowchart illustrating an embodiment of step S14 of this application, which determines the uniformity of noise reduction performance of the headphones under test. It should be noted that if substantially the same result is obtained, this embodiment does not necessarily reflect that outcome. Figure 4 The illustrated process sequence is limited. This embodiment uses the following steps to calculate the uniformity of noise reduction performance: S31: Perform an arithmetic average of the at least two noise suppression values ​​to obtain the average noise suppression value of the headphone under test.

[0054] The average noise suppression can be calculated using the following formula: .

[0055] in, N represents the average noise suppression level, and N represents the total number of noise suppression levels. This represents the i-th noise suppression value.

[0056] S32: The standard deviation is calculated based on the deviation between each of the noise suppression amounts and the average noise suppression amount.

[0057] The standard deviation can be calculated using the following formula: .

[0058] S33: The uniformity of noise reduction performance is obtained by normalization operation based on the ratio of the standard deviation to the average noise suppression amount.

[0059] The uniformity of noise reduction performance can be calculated using the following formula: .

[0060] uniformity of noise reduction performance The closer the value is to 1, the higher the uniformity of noise reduction performance across all directions, and the smaller the fluctuation in NR values ​​across directions. In other words, the more consistent the noise processing capabilities of the headphones across all directions; the uniformity of noise reduction performance. The closer the value is to a smaller value, the lower the uniformity of the noise cancellation performance of the tested headphones in all directions, and the greater the fluctuation of the NR value in each direction. In other words, the tested headphones have a large deviation in their ability to process external environmental noise in each direction, resulting in a poor listening experience for users. R&D engineers can then use the test results to judge the noise cancellation performance of the headphones and make targeted improvements to the headphone's algorithm or acoustic structure to enhance its noise cancellation performance in specific directions (such as the rear), thereby optimizing the user experience of using noise-canceling headphones in real-world complex environments.

[0061] In a specific application scenario, the noise suppression amount in several directions of the simulated human head model 110 is measured according to the above steps S11~S13. : Based on the above information, the average noise suppression amount can be determined as: =12dB; Standard deviation: The uniformity of noise reduction performance is as follows: 0.8092.

[0062] The tests revealed that the noise reduction (NR) value of this headset was 15dB at the front (0°), but only 8dB at the rear (180°). The calculated DUI value was 0.8092. This result indicates that the Bluetooth headset's noise reduction performance from the front (15dB) is significantly better than its noise reduction performance from the rear (8dB). The DUI value of 0.8092 (close to 1 indicates uniformity) suggests a certain degree of non-uniformity in its directional noise reduction performance. This information is of significant guiding value for product development, helping engineers to specifically improve the headset's algorithms or acoustic structure to enhance its rear noise reduction performance, thereby optimizing the user's call experience in complex real-world environments.

[0063] Please see Figure 5 , Figure 5 This is a schematic block diagram of an embodiment of the headphone noise suppression testing device of this application. The headphone noise suppression testing device 900 includes a processor 910 and a memory 920 coupled to each other. The memory 920 stores a computer program, and the processor 910 is used to execute the computer program to implement the headphone noise suppression testing method described in the above embodiments.

[0064] For a description of each step of the processing, please refer to the description of each step in the embodiment of the headphone noise suppression test method of this application above, and it will not be repeated here.

[0065] The memory 920 can be used to store program data and modules. The processor 910 executes various functional applications and data processing by running the program data and modules stored in the memory 920. The memory 920 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, application programs required for at least one function (such as control signal transmission function, audio signal acquisition function, audio signal processing function, etc.), etc. The data storage area may store data created based on the use of the headphone noise suppression test device 900 (reference audio signal, noise-reduced frequency signal, noise suppression parameters, noise reduction performance uniformity parameters, etc.). In addition, the memory 920 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device. Accordingly, the memory 920 may also include a memory controller to provide the processor 910 with access to the memory 920.

[0066] In the various embodiments of this application, the disclosed methods, apparatus, and devices can be implemented in other ways. For example, the embodiments of the headphone noise suppression testing device described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between devices or units through some interfaces, and may be electrical, mechanical, or other forms.

[0067] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0068] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0069] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium.

[0070] See Figure 6 , Figure 6 This is a schematic block diagram of a computer-readable storage medium according to an embodiment of the present application. The computer-readable storage medium 700 stores program data 710, which, when executed, implements the steps of the above embodiments of the headphone noise suppression test method.

[0071] For a description of each step of the processing, please refer to the description of each step in the embodiment of the headphone noise suppression test method of this application above, and it will not be repeated here.

[0072] The computer-readable storage medium 700 can be any medium capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0073] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features of the invention herein.

Claims

1. A headphone noise suppression testing system, characterized in that, The system includes: A simulated human head model, equipped with simulated human ears for mounting a reference microphone and the earphone to be tested; A sound source array, arranged around the simulated human head model, is used to emit test signals in different directions to the simulated human head model; The control processing unit is connected to the sound source array, the reference microphone, and the earphone under test. It is used to control the sound source array to emit test signals, acquire the reference audio signal obtained by the reference microphone in the ear canal of the simulated human head model to collect the test signals, and simultaneously acquire the noise-reduced frequency signal obtained by the earphone under test worn by the simulated human head model to collect the test signals. The control processing unit is further configured to determine the noise suppression amount based on the reference audio signal and the noise-canceling frequency signal, and to determine the uniformity of the noise reduction performance of the headphone under test in different directions based on at least two noise suppression amounts corresponding to at least two test signals emitted by the sound source array in at least two different directions.

2. The testing system according to claim 1, characterized in that, The control processing unit is further configured to: obtain the noise suppression amount in the corresponding direction by logarithmic operation based on the energy ratio of the sum of the signal energy of the reference audio signal to the sum of the signal energy of the noise-reduced frequency signal.

3. The testing system according to claim 1, characterized in that, The control processing unit is also used for: The average noise suppression value of the earphone under test is obtained by averaging the at least two noise suppression values. The standard deviation is calculated based on the deviation of each noise suppression measure from the average noise suppression measure. The uniformity of noise reduction performance is obtained by normalization based on the ratio of the standard deviation to the average noise suppression.

4. The testing system according to claim 1, characterized in that, The sound source array consists of a set number of loudspeakers, which are evenly distributed on a horizontal circle or a three-dimensional sphere centered on the simulated human head model.

5. The testing system according to claim 4, characterized in that, The loudspeakers are evenly distributed on a horizontal circle centered on the simulated human head model. The number of loudspeakers is at least 4, and the angle between the lines connecting adjacent loudspeakers and the simulated human head model is in the range of 40° to 90°.

6. The testing system according to claim 4, characterized in that, If the loudspeakers are evenly distributed on a three-dimensional sphere with the simulated human head model as the center, at least two loudspeakers are distributed above the horizontal plane where the simulated human head model is located, and at least two loudspeakers are distributed below the horizontal plane where the simulated human head model is located.

7. The testing system according to claim 6, characterized in that, The number of speakers is at least 6. The speakers located above the horizontal plane where the simulated human head model is located have a pitch angle of 30° to 60° relative to the simulated human head model, and the speakers located below the horizontal plane where the simulated human head model is located have a pitch angle of -60° to -30° relative to the simulated human head model.

8. A method for testing headphone noise suppression, applied to the testing system described in claims 1-7, characterized in that, The method includes: Control the sound source array to emit test signals; The reference audio signal obtained by the reference microphone in the ear canal of the simulated human head model is acquired by collecting the test signal, and the noise-reduced audio signal obtained by the earphone worn by the simulated human head model is acquired by collecting the test signal. The noise suppression amount is determined based on the reference audio signal and the noise-reduced audio signal; The uniformity of noise reduction performance of the headphone under test in different directions is determined based on at least two noise suppression values ​​corresponding to at least two test signals emitted from at least two different directions by the sound source array.

9. A headphone noise suppression testing device, characterized in that, The device includes a processor and a memory coupled to each other; the memory stores a computer program, and the processor executes the computer program to implement the steps of the method as claimed in claim 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores program data that, when executed by a processor, implements the steps of the method as described in claim 8.

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