Noise reduction earphone wearing state detection method and device and audio compensation method and device

Abstract

The invention discloses a noise reduction earphone wearing state detection method and device and an audio compensation method and device. The noise reduction earphone comprises a loudspeaker located in a cavity formed by the noise reduction earphone and an ear canal and a feedback microphone arranged near the loudspeaker, and the wearing state detection method comprises the following steps: determining a first transfer function TF according to an audio channel signal and a feedback audio signal, acquiring a second transfer function G by at least utilizing the first transfer function TF and the frequency response Hb of the feedback noise reduction filter, and detecting the wearing state of the noise reduction earphone according to the second transfer function G; the audio compensation method comprises the following steps: determining a first transfer function TF according to an audio channel signal and a feedback audio signal, carrying out stability judgment on the first transfer function TF, and when the first transfer function TF is stable, compensating the first transfer function TF based on the amplitude difference between the first transfer function TF and a second target transfer function TFd, and compensating the audio of the noise reduction earphone by using the compensated first transfer function TF.

Description

Technical Field

[0001] The present application relates to the field of earphone technology, and in particular to a method and device for detecting the wearing status of noise-cancelling earphones, and a method and device for audio compensation. Background Art

[0002] Headphones are increasingly used in daily life because of their small size and portability. The noise reduction and listening effects of headphones are very important to users. Noise reduction headphones are becoming more and more popular among users because they can reduce external noise heard by the human ear and reduce noise interference.

[0003] This application found the following problems in the process of implementing noise-canceling headphones:

[0004] First, the audio effect of noise-canceling headphones is affected by the wearing state.

[0005] When the headphones are worn properly, they usually have a better noise reduction effect. When they are not worn properly, the noise reduction effect will be seriously affected.

[0006] If the current wearing status of the noise-canceling headphones can be detected, the user's hearing experience can be improved according to the wearing status. For example, a warning sound can be used to remind the user to adjust the wearing of the noise-canceling headphones. If the headphones are currently worn loosely, the user is reminded that the headphones are not worn properly. The user can adjust the position and angle of the headphones or replace the earmuffs appropriately to improve the audio effect of the noise-canceling headphones.

[0007] Second, the audio effect of noise-canceling headphones is also affected by the audio compensation filter.

[0008] In noise-cancelling headphones, when there is a feedback noise reduction module, or when the feedback noise reduction is in operation, the audio effect is not only affected by the wearing state, but also by the amount of feedback noise reduction. Feedback noise reduction usually causes the audio in the main noise reduction frequency band to attenuate, so an audio compensation module is designed in the audio path of the noise-cancelling headphones to compensate for the effect of feedback noise reduction on the audio. However, the audio compensation module is usually an audio compensation filter with a limited filter order that is designed in advance when the headphones and ear canal are well coupled. The audio compensation filter cannot compensate for the effect of feedback noise reduction on the audio well, and often leads to insufficient compensation for some frequency bands and lift in some frequency bands, resulting in a certain gap between the actual audio effect and the ideal audio effect. Or even if the audio compensation filter can compensate for part of the attenuation of the audio caused by feedback noise reduction, in the scenario where the headphones are not worn properly, there may still be some leakage or lift in the low-frequency part, and the effect on the low-frequency part caused by the improper wearing state of the headphones cannot be compensated by the audio compensation filter. Summary of the invention

[0009] The purpose of the embodiments of the present application is to solve at least one of the above-mentioned technical defects. In particular, a method and device for detecting the wearing status of noise-cancelling headphones, and a method and device for audio compensation are proposed. The audio effect of the noise-cancelling headphones is improved by improving the detection accuracy of the wearing status of the headphones and performing effective audio compensation processing on the noise-cancelling headphones.

[0010] The present application embodiment adopts the following technical solutions:

[0011] In a first aspect, an embodiment of the present application provides a method for detecting a wearing state of a noise-canceling headset, wherein the noise-canceling headset includes a speaker located in a cavity formed by the noise-canceling headset and an ear canal, and a feedback microphone disposed near the speaker, and the method for detecting a wearing state of the noise-canceling headset includes:

[0012] Acquire an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal;

[0013] Obtaining a second transfer function G between the speaker and the feedback microphone using at least the first transfer function TF and a frequency response Hb of a feedback noise reduction filter;

[0014] The wearing state of the noise reduction headset is detected according to the second transfer function G.

[0015] In a second aspect, an embodiment of the present application further provides a noise reduction headset audio compensation method, wherein the noise reduction headset includes a speaker located in a cavity formed by the headset and the ear canal and a feedback microphone arranged near the speaker, and the noise reduction headset audio compensation method includes:

[0016] Acquire an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal;

[0017] Performing stability judgment on the first transfer function TF;

[0018] When the first transfer function TF is stable, the first transfer function TF is compensated based on the amplitude difference between the first transfer function TF and a second target transfer function TFd; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when active noise reduction is turned off.

[0019] In a third aspect, an embodiment of the present application further provides a noise-canceling headphone wearing state detection device, wherein the noise-canceling headphone includes a speaker located in a cavity formed by the noise-canceling headphone and an ear canal, and a feedback microphone arranged near the speaker, wherein the noise-canceling headphone wearing state detection device includes:

[0020] a first calculation unit, configured to obtain an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal;

[0021] A second calculation unit, configured to obtain a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter;

[0022] A state detection unit is used to detect the wearing state of the noise reduction headset according to the second transfer function G.

[0023] In a fourth aspect, the present application also provides a noise reduction headphone audio compensation device, wherein the noise reduction headphone comprises a speaker located in a cavity formed by the headphone and the ear canal and a feedback microphone arranged near the speaker, wherein the noise reduction headphone audio compensation device comprises:

[0024] a third calculation unit, configured to obtain an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal;

[0025] a first stability judgment unit, configured to perform stability judgment on the first transfer function TF;

[0026] The first compensation unit is used to compensate the first transfer function TF based on the amplitude difference between the first transfer function TF and a second target transfer function TFd when the first transfer function TF is stable; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when the active noise reduction is turned off.

[0027] In a fifth aspect, an embodiment of the present application further provides a noise reduction headset, the noise reduction headset comprising a speaker located in a cavity formed by the headset and the ear canal and a feedback microphone arranged near the speaker, and further comprising:

[0028] a memory storing computer executable instructions;

[0029] A processor, when the computer executable instructions are executed, the processor executes a noise-canceling headphone wearing state detection method or a noise-canceling headphone audio compensation method.

[0030] In a sixth aspect, an embodiment of the present application further provides a computer-readable storage medium, which stores one or more programs, and when the one or more programs are executed by noise-canceling headphones including multiple application programs, the noise-canceling headphones execute a noise-canceling headphone wearing state detection method or a noise-canceling headphone audio compensation method.

[0031] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects:

[0032] In the embodiment of the present application, the first transfer function TF between the audio path and the feedback microphone is calculated through the audio path signal and the feedback audio signal collected by the feedback microphone. Since the audio path signal is not interfered by active noise reduction, the audio path signal will not be seriously polluted by noise and is a completely useful signal. The feedback audio signal after noise reduction processing also has a high signal-to-noise ratio. Therefore, the first transfer function TF calculated through these two signals has a strong anti-interference ability. In this way, the second transfer function G between the speaker and the feedback microphone calculated according to the first transfer function TF can also be unaffected by active noise reduction. The characteristics of the second transfer function G when the noise reduction headset is in different wearing states can realize accurate detection of the wearing state of the noise reduction headset.

[0033] Since the first transfer function TF represents the user's actual hearing sensation, that is, the first transfer function TF represents the audio effect affected by factors such as feedback noise reduction and wearing status, the embodiment of the present application compensates for the first transfer function TF by utilizing the amplitude difference between the first transfer function TF and the second target transfer function TFd. The compensated first transfer function TF can effectively compensate for the audio of the noise reduction headphones, so that the user can obtain a hearing experience closer to the ideal audio effect without adjusting the wearing status of the noise reduction headphones. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0035] Figure 1 A schematic diagram of the positional relationship between the speaker and the feedback microphone in the noise reduction headset shown in the embodiment of the present application;

[0036] Figure 2 This is a schematic diagram of the signal flow in the noise reduction headphones shown in the embodiment of the present application;

[0037] Figure 3 This is a flow chart of a method for detecting the wearing status of a noise-cancelling headset shown in an embodiment of the present application;

[0038] Figure 4 It is a schematic diagram of comparing frequency domain curves of the second transfer function under different wearing states shown in the embodiment of the present application;

[0039] Figure 5 It is a schematic diagram of comparing the time domain curves of the second transfer function under different wearing states shown in the embodiment of the present application;

[0040] Figure 6 This is a schematic diagram of the overall process of detecting the wearing status of a noise-cancelling headset shown in an embodiment of the present application;

[0041] Figure 7 This is a flow chart of a noise reduction headset audio compensation method shown in an embodiment of the present application;

[0042] Figure 8 This is a schematic diagram of the overall process of audio compensation for a noise reduction headset shown in an embodiment of the present application;

[0043] Fig. 9 This is a schematic diagram of the structure of a noise reduction headphone wearing state detection device shown in an embodiment of the present application;

[0044] Fig.10 This is a schematic structural diagram of an audio compensation device for noise reduction headphones shown in an embodiment of the present application;

[0045] Fig.11 A schematic diagram of the structure of a noise-cancelling headset shown in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0047] To facilitate understanding of the following embodiments of the present application, the noise reduction headphones according to the embodiments of the present application are first introduced.

[0048] The noise reduction earphone of the embodiment of the present application includes a speaker located in a sealed cavity formed by the noise reduction earphone and the ear canal, and a feedback microphone arranged near the speaker. Figure 1 As shown, the speaker and the feedback microphone are respectively arranged in their own cavities, and the feedback microphone is arranged near the speaker.

[0049] The noise reduction headphones of the embodiment of the present application include an audio path, a feedback noise reduction path and an optional feedforward noise reduction path, wherein the audio path includes an audio compensation module, the feedback noise reduction path includes a feedback noise reduction filter, and the feedforward noise reduction path includes a feedforward noise reduction filter.

[0050] like Figure 2 As shown, the audio path can be understood as the signal path formed by the audio source signal Ref1 emitted from the audio source passing through the audio compensation module (FBEQ filter module) to the speaker input terminal, the feedback noise reduction path can be understood as the signal path formed by the feedback noise reduction filter from the output terminal of the feedback microphone to the speaker input terminal, and the feedforward noise reduction path can be understood as the signal path formed by the feedforward noise reduction microphone FFmic passing through the feedforward noise reduction filter to the speaker input terminal. It should be noted that the embodiment of the present application improves the audio path of the existing noise reduction headphones, and additionally designs an intelligent filtering module SmartEQ in the audio path of the noise reduction headphones. That is, different from the prior art, the audio compensation module of the embodiment of the present application includes two parts: one is the intelligent filtering module SmartEQ, and the other is the feedback filtering module FBEQ.

[0051] In the normal wearing state, the feedforward noise reduction microphone FFmic is located outside the ear canal to pick up external noise signals and input them to the speaker for noise reduction processing. It can be understood that the embodiment of the present application exemplarily shows that the noise reduction headset includes a feedforward noise reduction path, and in other embodiments of the present application, the feedforward noise reduction path may not be included.

[0052] In the prior art, the audio compensation module usually only includes Figure 2 The feedback filter module FBEQ in the feedback filter module compensates for the audio attenuation caused by feedback noise reduction. The feedback filter module can be understood as a series of filter groups designed in advance according to different preset feedback noise reduction levels when the noise reduction headphones and ear canal are well coupled. The purpose is to compensate for the audio attenuation caused by feedback noise reduction. The specific parameter values ​​of these filter groups are determined by the measurement values ​​of a large amount of real wearing data in the laboratory before the headphones leave the factory. Since the feedback filter module belongs to the conventional design in this field, it will not be elaborated on here.

[0053] The embodiment of the present application performs compensation processing on the audio path signal through the intelligent filtering module to make up for the over-compensation or insufficient compensation of the feedback noise reduction by the feedback filtering module, and compensates for the low-frequency part affected by the inappropriate wearing state of the headphone. After multiple compensation processing, the user can obtain a listening experience that is closer to the ideal audio effect in real time.

[0054] As mentioned above, the audio effect of noise-canceling headphones is affected by the wearing state of the noise-canceling headphones and the audio compensation algorithm. In view of this, some existing technical solutions propose to perform wearing state detection and audio compensation processing based on the infrasound information contained in the speaker and the amplitude of the infrasound signal collected by the microphone; or to use the source audio signal and the feedback audio signal to perform wearing state detection and audio compensation processing according to the difference of the weighted sum of their low-frequency band amplitudes.

[0055] Such solutions either have specific requirements for the sound source signal or have poor noise reduction performance, which limits the use of noise reduction headphones. Therefore, in other existing technical solutions, it is proposed to perform wearing state detection and audio compensation processing by estimating the transfer function between the speaker and the microphone based on the speaker input signal and the feedback microphone signal placed at the acoustic front end of the speaker. Figure 2 As shown in the figure as an example, the prior art calculates the transfer function between the speaker and the microphone according to the input signal Mixsig of the speaker and the output signal of the feedback microphone FBmic.

[0056] Research has found that this solution has special requirements for the use scenarios of noise-cancelling headphones. For example, it needs to be used in scenarios where the external noise is extremely small or the audio volume is high. In this scenario, active noise reduction is not required (or active noise reduction is turned off). At this time, the signal-to-noise ratio of the input signal Mixsig is relatively high, so it can have a more accurate detection effect or audio compensation effect. However, in other scenarios where active noise reduction is required, the input signal Mixsig of the speaker is seriously polluted by noise due to the influence of the feedforward filter or feedback filter in the active noise reduction process. When the noise pollution is much greater than the useful signal, the transfer function obtained by the above solution will not be able to represent the actual wearing state, and due to the interference of active noise reduction on the input signal, it is also difficult to perform effective audio compensation.

[0057] In view of the above problems, the embodiment of the present application calculates the first transfer function TF between the audio path and the feedback microphone FBmic through the audio path signal and the feedback audio signal collected by the feedback microphone FBmic. Since the audio path signal is not interfered by active noise reduction (i.e., not affected by the feedforward filter and / or the feedback filter), the audio path signal will not be seriously polluted by noise and is a completely useful signal, and the feedback audio signal after noise reduction processing also has a high signal-to-noise ratio. Therefore, the first transfer function TF calculated by these two signals has a strong anti-interference ability, so the second transfer function G between the speaker and the feedback microphone calculated according to the first transfer function TF can also be unaffected by active noise reduction. The wearing state detection of the noise reduction headset is realized by the characteristics of the second transfer function G when the noise reduction headset is in different wearing states; in addition, since the first transfer function TF represents the user's real hearing sense, that is, the first transfer function TF represents the audio effect affected by factors such as feedback noise reduction and wearing state, by using the amplitude difference between the first transfer function TF and the second target transfer function TFd to compensate for the first transfer function TF, the user can obtain a hearing experience closer to the ideal audio effect in real time.

[0058] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0059] An embodiment of the present application provides a method for detecting a wearing state of a noise-canceling headset, wherein the noise-canceling headset includes a speaker located in a cavity formed by the noise-canceling headset and an ear canal, and a feedback microphone arranged near the speaker.

[0060] like Figure 3 As shown, a flowchart of a method for detecting the wearing state of a noise reduction headset in an embodiment of the present application is provided, and the method at least includes the following steps S310 to S330:

[0061] Step S310: acquiring an audio path signal and a feedback audio signal collected by the feedback microphone, and determining a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal.

[0062] In the noise reduction headphones of the embodiment of the present application, the input signal MixSig of the speaker is usually a mixed signal of the following three signals, such as Figure 2 As shown in FIG. 1 , they are respectively an audio path signal, a feedback noise reduction path signal and a feedforward noise reduction path signal. Among them, the audio path signal can be Figure 2The audio signal Ref1 in the source audio signal, the audio signal Ref after being processed by the smart filter module, or the audio signal Ref2 after being processed by the feedback filter module. It is easy to know that when the parameters of the smart filter module SmartEQ and the feedback filter module FBEQ are known, the three audio path signals Ref1, Ref and Ref2 can be converted to each other, and the other two items can be obtained based on one of them.

[0063] The feedforward noise reduction path signal refers to the signal after passing through the feedforward noise reduction filter. The feedforward microphone FFmic can obtain the external noise signal, and the feedforward filter can reduce the external noise signal (for example, attenuate the external noise signal so that the human ear can't hear the external noise as much as possible) or amplify the external noise signal (even if the external noise is transparent, so that the user can hear the external sound). In this application, the feedforward noise reduction path signal is optional. The feedback noise reduction path signal is the signal output by the feedback microphone FBmic and after passing through the feedback noise reduction filter.

[0064] It can be seen that the input signal MixSig of the speaker includes not only the useful signal in the audio path, but also the external noise signal mixed in by the feedforward noise reduction, and part of the external noise signal mixed in by the feedback noise reduction.

[0065] The prior art directly uses the input signal MixSig of the speaker and the feedback audio signal of the feedback microphone FBmic to calculate the transfer function between the speaker and the feedback microphone. The reliability of the transfer function is poor. When the input signal MixSig is severely polluted by noise and its signal-to-noise ratio is low, the transfer function will seriously deviate from the target transfer function, making it difficult to accurately determine the wearing status of the headphone.

[0066] In response to the above problem, the embodiment of the present application first calculates the first transfer function TF between the audio path and the feedback microphone, and then based on the physical relationship between the two paths, the audio path and the feedback microphone, and the speaker and the feedback microphone, the second transfer function G is indirectly calculated in combination with the first transfer function TF. Since the first transfer function TF is calculated using the audio path signal and the feedback audio signal, it is not affected by external noise (or is insensitive to external noise interference), and the calculation process between the two transfer functions is a derivation and transformation process of mathematical expressions, which is also not affected by external noise. Therefore, the obtained second transfer function G can characterize the actual wearing state of the noise cancelling headphones, thereby being able to accurately detect the wearing state of the noise cancelling headphones without being restricted by the usage scenarios of the noise cancelling headphones.

[0067] Step S320: Acquire a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and the frequency response Hb of the feedback noise reduction filter.

[0068] refer to Figure 2, a first path between the audio path and the feedback microphone FBmic and a second path between the loudspeaker and the feedback microphone FBmic satisfy a certain physical relationship. Based on the physical relationship, a relationship expression between the first transfer function TF and the second transfer function G can be pre-calculated. Based on the relationship expression and at least using the first transfer function TF and the frequency response Hb of the feedback noise reduction filter, the second transfer function G can be obtained.

[0069] Step S330: detecting the wearing state of the noise reduction headset according to the second transfer function G.

[0070] The "wearing state" of the embodiment of the present application can be understood as the coupling state (or degree of fit) between the noise-canceling earphones and the ear canal. The wearing state can include suitable wearing or inappropriate wearing, where suitable wearing corresponds to good coupling between the noise-canceling earphones and the ear canal (or the noise-canceling earphones and the ear canal fit well), and inappropriate wearing corresponds to poor coupling between the noise-canceling earphones and the ear canal (or the noise-canceling earphones and the ear canal fit loosely).

[0071] As mentioned above, the second transfer function G exhibits different characteristics when the noise reduction headset is in different wearing states, for example, Figure 4 In the frequency domain scenario shown, two frequency domain curves of the second transfer function G in the case of suitable wearing and inappropriate wearing are shown (the frequency domain curve of inappropriate wearing corresponds to Figure 4 The dotted line in the figure corresponds to the frequency domain curve of wearing a suitable Figure 4 When the noise reduction headphones are not worn properly, the energy of the low-frequency band of 100Hz-700Hz is low due to the leakage of low-frequency energy. However, in the frequency domain curve when the headphones are worn properly, the energy corresponding to this frequency band is higher.

[0072] For example, Figure 5 In the time domain scenario shown, the time domain curves of the second transfer function G in the case of suitable wearing and inappropriate wearing are shown (where the time domain curve of inappropriate wearing corresponds to Figure 5 The loose dotted line in Figure 5 The dense dashed line in the figure is the first target transfer function Gd, which is used as the reference standard for wearing status detection. The time domain curve corresponding to the appropriate wearing state is: Figure 5 When the noise cancelling headphones are not worn properly, the Euclidean distance to the first target transfer function Gd in the low frequency band of 200Hz-300Hz is much larger than the Euclidean distances in other frequency bands. When the noise cancelling headphones are worn properly, the Euclidean distance to the first target transfer function Gd in the low frequency band of 200Hz-300Hz is not much different from the Euclidean distances in other frequency bands.

[0073] In this way, in the time domain, the embodiment of the present application can determine the wearing state of the noise cancelling headphones based on the difference between the second transfer function G and the first target transfer function Gd; and in the frequency domain, the wearing state of the noise cancelling headphones can be determined according to the energy difference between the second transfer function G and the first target transfer function Gd at the target frequency band (for example, the low frequency band of 100Hz-700Hz).

[0074] Among them, the first target transfer function Gd is the transfer function from the speaker to the feedback microphone FBmic obtained when the noise reduction headphones and the ear canal are well coupled. The embodiment of the present application can be obtained in advance through measurement in the laboratory. For example, the average second transfer function of multiple people wearing the headphones properly can be used as the first target transfer function Gd, or the second transfer function in the proper wearing state can be obtained according to a standard ear canal simulation device as the first target transfer function Gd.

[0075] The difference between the second transfer function G and the first target transfer function Gd in the embodiment of the present application can be a distance difference in the time domain or an energy difference in the frequency domain. Detecting the wearing state of the noise reduction headphones based on the difference is a common design in the art and will not be elaborated on here.

[0076] The first transfer function TF of the embodiment of the present application includes, for example, an estimated value of the first transfer function TF and an expression of the first transfer function TF, wherein the expression of the first transfer function TF includes at least the first transfer function TF and the frequency response Hb of the feedback noise reduction filter. In some embodiments of the present application, determining the first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal in the above step S310 specifically includes:

[0077] Processing the audio path signal and the feedback audio signal using a preset algorithm to obtain an estimated value of the first transfer function TF;

[0078] A signal expression of the feedback audio signal and a signal expression of the audio path signal are obtained, and an expression of the first transfer function TF is constructed according to the signal expression of the feedback audio signal and the signal expression of the audio path signal.

[0079] In some possible implementation schemes of this embodiment, an estimated value of the first transfer function TF may be calculated using an adaptive filtering algorithm, that is, the feedback audio signal is used as a target signal, the audio path signal is used as a reference signal, and a time domain transfer function is obtained using an adaptive filtering algorithm, and an estimated value of the first transfer function TF is obtained after Fourier transformation. Of course, the estimated value of the first transfer function TF may also be calculated using a periodogram algorithm, specifically: a cross spectrum of the audio path signal and the feedback audio signal, and an autospectrum of the audio path signal are obtained, and an estimated value of the first transfer function TF is obtained according to the ratio of the cross spectrum to the autospectrum.

[0080] In some other possible implementation schemes of this embodiment, the expression of the first transfer function TF constructed according to the signal expression of the feedback audio signal and the signal expression of the audio path signal is as shown in the following formula (1):

[0081]

[0082] In the above formula (1), FBmicSig is the feedback audio signal, Ref2 is an audio path signal, E[] is a statistical mean operator, and E[FBmicSig*Ref2 * ] is the cross spectrum, E[Ref2*Ref2 * ] is my own composition, A * is the conjugate of A. Here, for the convenience of description, Ref2 is selected as the input signal of FBEQ. Based on the subsequent description, other reference signals on the audio signal path can also be selected, such as Ref1, Ref3 as input. The TF and G obtained by different endpoints as input are slightly different)

[0083] Combination Figure 2 As shown, the expression of the feedback audio signal FBmicSig is shown in the following formula (2):

[0084] FBmicSig=(Ref2*FBEQ+FBmicSig*Hb+FFMicSig*Hf)*G (2)

[0085] In the above formula (2), FBEQ is the frequency response of the feedback filter module, FFmicSig is the external noise signal collected by the feedforward microphone, Hb is the frequency response of the feedback noise reduction filter, and TF is the frequency response of the feedforward noise reduction filter.

[0086] According to the above formula (1) and formula (2), an expression of the first transfer function TF can be obtained as follows:

[0087]

[0088] Since FFmicSig is an external noise signal and Ref2 is a useful signal, the two signals are completely unrelated, so the statistical mean of the two signals is 0, that is, E[FFmicSig*Ref2 * ]=0, in this case, the expression of the first transfer function TF can be obtained as follows:

[0089] TF=FBEQ*G+TF*Hb*G (4)

[0090] In this way, the expression of the constructed first transfer function TF can be obtained through this implementation scheme. It can be seen from formula (4) that the expression of the first transfer function TF includes the second transfer function G to be obtained. After obtaining the estimated value of the first transfer function TF, the frequency response FBEQ and Hb, the second transfer function G can be obtained through formula (4).

[0091] As can be seen above, the audio path signal in the above step S310 is one of the following three:

[0092] A first audio path signal, which is a source audio signal; or

[0093] A second audio path signal, which is a source audio signal processed by an intelligent filtering module; or

[0094] The third audio path signal is the source audio signal processed by the intelligent filtering module and the feedback filtering module.

[0095] Specifically, in Figure 2 In the scenario shown, the first audio path signal is Figure 2 The source audio signal Ref1 in the second audio path signal is Figure 2 The signal Ref2 in the third audio path is Figure 2 The signal Ref3 in the above formula (4) is an expression of the first transfer function TF when the audio path signal is the second audio path signal. When the audio path signal is the first audio path signal or the third audio path signal, the expression of the first transfer function TF is slightly different.

[0096] Specifically, when the audio path signal is the first audio path signal Ref1, the expression of the feedback audio signal FBmicSig is as shown in the following formula (5):

[0097] FBmicSig=(Ref1*SmartEQ*FBEQ+FBmicSig*Hb+FFmicSig*Hf)*G (5)

[0098] According to the above formula (1) and formula (5), another expression of the first transfer function TF can be obtained as follows:

[0099]

[0100] Thus, when the audio path signal is the first audio path signal, the expression of the first transfer function TF is TF1=FBEQ*SmartEQ*G+TF1*Hb*G, where SmartEQ is the frequency response of the smart filter module, and its value can adopt the historical value calculated last time.

[0101] When the audio path signal is the third audio path signal Ref3, the expression of the feedback audio signal is as shown in the following formula (7):

[0102] FBmicSig=(Ref3+FBmicSig*Hb+FFmicSig*Hf)*G (7)

[0103] According to the above formula (1) and formula (7), another expression of the first transfer function TF can be obtained as follows:

[0104]

[0105] Thus, when the audio path signal is the third audio path signal, the expression of the first transfer function TF is TF2=G+TF2*Hb*G.

[0106] Thus, through the above embodiment, the expression of the first transfer function TF corresponding to each audio path signal can be obtained, and by deriving and transforming the expressions of the above three first transfer functions, the expression of the second transfer function G can be obtained:

[0107]

[0108] In this way, the expression of the second transfer function G can be obtained through the above-mentioned embodiment of the present application. According to formula (9) to formula (11), in the expression of the second transfer function G, the frequency responses FBEQ, Hb, and SmartEQ are all known values. The estimated value of the first transfer function TF can also be obtained through the embodiment of the present application. By substituting each frequency response value and the estimated value of the first transfer function TF into the corresponding expression of the second transfer function G, the second transfer function G required by the embodiment of the present application can be obtained.

[0109] It can be seen that in the above step S320, at least the first transfer function TF and the frequency response Hb of the feedback noise reduction filter are used to obtain the second transfer function G between the speaker and the feedback microphone, which specifically includes the following three situations:

[0110] When the audio path signal selects the third audio path signal, the second transfer function G is obtained by using the first transfer function and the frequency response Hb of the feedback noise reduction filter;

[0111] When the audio path signal selects the second audio path signal, the second transfer function G is also obtained based on the frequency response FBEQ of the feedback filter module;

[0112] When the audio path signal selects the first audio path signal, the second transfer function G is also acquired based on the frequency response SmartEQ of the smart filter module and the frequency response FBEQ of the feedback filter module.

[0113] Specifically, when the first audio path signal is selected, according to the expression of the second transfer function G1 in the above formula (10), the estimated value of the first transfer function TF1, the frequency response FBEQ, the last calculated SmartEQ historical value, and the frequency response Hb are substituted into the formula (10), and the second transfer function G1 is calculated accordingly.

[0114] When the second audio path signal is selected, according to the expression of the second transfer function G in the above formula (9), the estimated value of the first transfer function TF, the frequency response FBEQ, and the frequency response Hb are substituted into the formula (9) to calculate the second transfer function G.

[0115] When the third audio path signal is selected, according to the expression of the second transfer function G2 in the above formula (11), the estimated value of the first transfer function TF2 and the frequency response Hb are substituted into the formula (11), thereby calculating the second transfer function G2.

[0116] In some embodiments of the present application, when executing the above step S310, the above Figure 3 The methods also include:

[0117] Performing stability judgment on the first transfer function TF to determine a stability judgment result of the first transfer function TF, wherein the stability judgment result includes that the first transfer function TF is stable or the first transfer function TF is unstable;

[0118] When the first transfer function TF is stable, obtaining a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter;

[0119] When the first transfer function TF is unstable, the second transfer function G is obtained without using the first transfer function TF.

[0120] In this embodiment, the stability of the first transfer function TF is determined, and the second transfer function G is calculated using only the stable first transfer function TF, so that the accuracy of the second transfer function G can be further guaranteed.

[0121] In some possible implementation schemes of this embodiment, performing stability judgment on the first transfer function TF specifically includes:

[0122] Obtaining the correlation between the audio path signal and the feedback audio signal, and / or obtaining the volatility of the first transfer function TF within a preset time, where the preset time is, for example, 0.5 seconds or other duration;

[0123] The stability of the first transfer function TF is judged according to the correlation and / or the volatility.

[0124] Specifically, the correlation is the correlation of the two signals, and the volatility is the variance of the first transfer function TF. When the correlation is greater than a set correlation value and the variance is less than a set variance value, it is determined that the first transfer function TF is stable, otherwise it is determined that the first transfer function TF is unstable.

[0125] It is understandable that the embodiment of the present application may also use other parameters to represent the correlation between the two signals, and use other parameters to represent the volatility of the first transfer function TF, and the embodiment of the present application does not impose specific limitations on this.

[0126] In some embodiments of the present application, the above Figure 3 The methods also include:

[0127] The first transfer function TF is compensated based on the difference in magnitude between the first transfer function TF and a second target transfer function TFd.

[0128] Among them, the second target transfer function TFd is the transfer function from the audio path to the feedback microphone FBmic when the active noise reduction is turned off. The embodiment of the present application can obtain TFd in advance through measurement in the laboratory. For example, the average transfer function can be used as the second target transfer function TFd based on the measurement values ​​of multiple people under suitable wearing conditions, or the transfer function in a suitable wearing state can be obtained based on a standard ear canal simulation device as the second target transfer function TFd.

[0129] In some application scenarios, when it is determined that the first transfer function TF is stable, the first transfer function TF may be compensated. The compensation is achieved based on adjusting the frequency response SmartEQ of the smart filter module, for example, the first transfer function TF is compensated by adjusting the frequency response SmartEQ of the smart filter module, wherein the specific compensation implementation scheme for the first transfer function TF will be described in detail in subsequent embodiments.

[0130] When the embodiment of the present application detects the wearing status of the noise-cancelling headphones, the first transfer function TF can also be compensated according to a certain strategy, such as periodically performing compensation processing of the first transfer function TF, or compensating the first transfer function TF based on the wearing status detection result. By compensating the first transfer function TF, the compensated first transfer function TF is made more accurate, thereby improving the accuracy of the second transfer function G.

[0131] Combine the following Figure 6 The wearing status detection process of the noise reduction headphones according to the embodiment of the present application is described in detail.

[0132] In the embodiment of the present application, the audio path signal is used as one input of the algorithm. For the convenience of description, the acquisition point signal Ref2 is selected as one input of the algorithm. In other embodiments, Ref1 or Ref3 can also be selected as the input. When Ref1 or Ref3 is selected as the input, the calculation principle of the second transfer function G is the same, but the expression of the calculated second transfer function G is slightly different. This embodiment is specifically described with Ref1 as the input, and the other input is the signal FBmicSig collected by the feedback microphone FBmic.

[0133] like Figure 6 As shown, the wearing status detection in the embodiment of the present application mainly includes the following main steps:

[0134] (1) Obtain the audio processing signal of the current frame.

[0135] One path is the signal sequence at the collection point Ref in the audio path, denoted as x=[x(0),x(1),......,x(N-1)], and the other path is the feedback audio signal sequence collected by the feedback microphone FBmic, denoted as y=x1+v=[x1(0),x1(1),......,x1(N-1)]+[v(0),v(1),......,v(N-1)], where x1 represents the signal of the audio path collected by the feedback microphone, and v represents other interference signals of the non-audio path collected by the feedback microphone, such as interference signals generated by external noise signals, talking and moving the mouth, etc.

[0136] In practical applications, after collecting two channels of signals, the two channels of signal sequences can be high-pass filtered to filter out the influence of the DC signal.

[0137] (2) Estimate the first transfer function TF by an adaptive filtering algorithm.

[0138] The first transfer function TF in the time domain is recorded as tf = [tf (1), tf (2), ..., tf (M)], where M represents the order of the filter tf, and d = y represents the target signal sequence, and represents an error signal sequence, the filter tf is adaptively updated according to the error function energy minimization criterion, and an estimate of the first transfer function TF is obtained according to the update result.

[0139] (3) Perform stability judgment on the first transfer function TF.

[0140] For example, stability is judged based on the correlation coh between x and y and the variance var of m consecutive (m is a positive integer greater than 1) frames TF. If the correlation coh is large enough and the variance var is small enough, for example, coh>0.85 and var<0.15, then the first transfer function TF is determined to be stable and can be adopted. Otherwise, it is considered to be unstable and will not be adopted. There is no specific limitation on the thresholds of the correlation coh and the variance var, and those skilled in the art can set them as needed.

[0141] (4) Calculate the second transfer function G.

[0142] According to the aforementioned formula (9), the second transfer function G is obtained by the frequency response FBEQ, the frequency response Hb and the estimated value of the first transfer function TF.

[0143] (5) Perform time-frequency domain transformation on the second transfer function G to obtain the second transfer function g in the time domain.

[0144] When performing time-frequency domain transformation processing, the effective frequency band of the second transfer function G can be selected, for example, 250Hz-700Hz is selected as the effective frequency band of the second transfer function G. By performing an inverse Fourier transform on the second transfer function G, the second transfer function g in the time domain can be obtained.

[0145] (6) Wearing status detection.

[0146] For example, the Euclidean distance between the second transfer function g and the first target transfer function gd is calculated by the following formula (12). If the Euclidean distance d is less than the distance threshold, the current wearing state of the noise cancelling headset is determined to be appropriate; otherwise, the current wearing state of the noise cancelling headset is determined to be inappropriate.

[0147]

[0148] Of course, in other embodiments of the present application, the current wearing state of the noise reduction headset may also be determined according to the energy difference between the second transfer function G in the frequency domain and the first target transfer function Gd in the frequency domain.

[0149] An embodiment of the present application also provides an audio compensation method for a noise-canceling headset, wherein the noise-canceling headset includes a speaker located in a cavity formed by the noise-canceling headset and an ear canal, and a feedback microphone arranged near the speaker.

[0150] like Figure 7 As shown, a flowchart of a noise reduction headset audio compensation method in an embodiment of the present application is provided, and the method at least includes the following steps S710 to S720:

[0151] Step S710: acquiring an audio path signal and a feedback audio signal collected by the feedback microphone, and determining a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal.

[0152] Step S720: performing stability determination on the first transfer function TF.

[0153] Step S730: When the first transfer function TF is stable, the first transfer function TF is compensated based on the amplitude difference between the first transfer function TF and the second target transfer function TFd, so as to perform audio compensation on the noise reduction headphone through the compensated first transfer function TF.

[0154] Among them, the second target transfer function TFd is the transfer function from the audio path to the feedback microphone FBmic obtained when the active noise reduction is turned off and the noise reduction headphones and the ear canal are well coupled. The embodiment of the present application can obtain TFd in advance through measurement in the laboratory. For example, the average transfer function of multiple people wearing the headphones properly can be used as the second target transfer function TFd, or the transfer function in the proper wearing state can be obtained based on a standard ear canal simulation device as the second target transfer function TFd.

[0155] As mentioned above, the existing technology directly uses the input signal MixSig of the speaker and the feedback audio signal of the feedback microphone to calculate the transfer function between the speaker and the feedback microphone, and performs audio compensation through the transfer function. However, in the active noise reduction scenario, the input signal MixSig is mixed with external noise signals, and the transfer function cannot represent the user's real hearing experience. Therefore, the audio compensation implemented based on the transfer function is difficult to achieve the ideal audio effect.

[0156] In response to the above problems, the embodiment of the present application uses the audio path signal and the feedback audio signal to calculate the first transfer function TF between the audio path and the feedback microphone. Since the audio path signal will not be seriously polluted by noise and is a completely useful signal, and the feedback audio signal after noise reduction processing also has a high signal-to-noise ratio, the first transfer function calculated by these two signals characterizes the audio effect after being affected by factors such as feedback noise reduction and wearing status, and can reflect the user's real hearing feeling. Therefore, based on the amplitude difference between the first transfer function TF and its corresponding second target transfer function TFd, the first transfer function TF is compensated, so that the first transfer function TF can reflect the current user's real hearing feeling in real time and accurately. Processing the source audio signal using the compensated first transfer function TF can effectively compensate for the problem of unsatisfactory audio hearing feeling caused by feedback noise reduction and inappropriate wearing status, and can improve the effectiveness of audio compensation, so that the noise reduction headphones are closer to the ideal audio effect.

[0157] In some embodiments of the present application, when the first transfer function TF is stable in the above step S730, based on the amplitude difference between the first transfer function TF and the second target transfer function TFd, the first transfer function TF is compensated, specifically including:

[0158] Perform frequency band processing on the first transfer function TF to obtain a plurality of discontinuous sub-frequency bands;

[0159] Obtaining the amplitude difference between the first transfer function TF and the second target transfer function TFd in each sub-frequency band;

[0160] Obtaining a compensation gain and a center frequency of each sub-frequency band according to the amplitude difference of each sub-frequency band;

[0161] A filter coefficient is obtained according to the compensation gain and the center frequency of each sub-frequency band, and a compensation result of the first transfer function TF is obtained according to the filter coefficient and the first transfer function TF.

[0162] Considering the human ear's listening range and the high-pass filtering and DC removal operation of the low-frequency part, the lower frequency part of the signal can be ignored, so that the audio of the target frequency band 80Hz-800Hz can be compensated. Considering the influence of the filter transition band, the embodiment of the present application divides the above target frequency band into 3 discontinuous sub-bands, for example, 80Hz-200Hz is used as the first frequency band, 250Hz-450Hz is the second frequency band, and 550Hz-750Hz is the third frequency band.

[0163] In each sub-band, find the frequency point with the maximum gain of the second target transfer function TFd as the center frequency of each sub-band. The compensation gain in each sub-band can be calculated by the following formula (13):

[0164] Gain bi (k) = A d_bi (k)-A est_bi (k) (13)

[0165] In formula (13), bi is the ith sub-band, A d_bi Table 1 shows the amplitude of the second target transfer function TFd in the i-th sub-frequency band, A est_bi is the amplitude of the first transfer function TF in the i-th sub-frequency band.

[0166] Then the maximum compensation gain MaxGain of each sub-band is bi And its corresponding center frequency k0 is shown in formula (14):

[0167]

[0168] After obtaining the compensation gain and the corresponding center frequency of each sub-band, each group of filter coefficients is calculated in combination with different bandwidths. For example, the bandwidth range is from 80Hz to 800Hz, with an incremental step of 10Hz. Each bandwidth corresponds to a group of filter coefficients. The first transfer function TF corresponding to each group of filters is multiplied by the group of filter coefficients to obtain the compensated first transfer function TF.

[0169] After obtaining the compensated first transfer function TF, the above Figure 7 The method shown also includes:

[0170] The frequency response SmartEQ of the smart filter module is adjusted by using the compensated first transfer function TF and the second target transfer function TFd, and the adjusted smart filter module is used to perform audio compensation on the noise reduction headset.

[0171] For example, if Figure 8 As shown, the compensated first transfer function TF is compared with the second target transfer function TFd to obtain the error value Err about the amplitude, and the target filter is calculated according to the mean square error minimum algorithm shown in the following formula (15):

[0172]

[0173] In formula (15), K is the total number of frequency points, k1 and k2 are the frequency points of 100 Hz and 800 Hz respectively.

[0174] The frequency response of the target filter corresponding to the minimum mean square error is used as the frequency response SmartEQ of the intelligent filtering module. In this way, real-time (or quasi-real-time) adjustment of the frequency response of the intelligent filtering module can be achieved. The source audio signal is filtered using the adjusted intelligent filtering module to improve the audio compensation effect of the noise reduction headphones, so that users can experience a more ideal listening effect.

[0175] This embodiment shows an implementation scheme for adjusting the frequency response SmartEQ of the smart filtering module. In other embodiments of the present application, a series of filter groups can be designed in advance according to the compensation gain, and then the frequency response of the corresponding filter can be selected as the frequency response SmartEQ of the smart filtering module according to the estimated compensation gain. Although this method is not as good as the real-time updated filter, it is easy to implement and can also improve the audio listening experience.

[0176] It should be noted that, since the human ear is insensitive to phase, the embodiment of the present application compensates for the amplitude of the source audio signal, that is, the intelligent filtering module filters the amplitude of the source audio signal to improve the amplitude compensation effect of the source audio signal.

[0177] like Fig. 9 As shown, a schematic diagram of the structure of a noise-canceling headset wearing state detection device in an embodiment of the present application is provided, wherein the noise-canceling headset includes a speaker located in a cavity formed by the noise-canceling headset and the ear canal and a feedback microphone arranged near the speaker, and the device 900 includes a first calculation unit 910, a second calculation unit 920 and a state detection unit 930;

[0178] A first calculation unit 910 is used to obtain an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal;

[0179] A second calculation unit 920 is used to obtain a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter;

[0180] The state detection unit 930 is used to detect the wearing state of the noise reduction headset according to the second transfer function G.

[0181] In some embodiments of the present application, the audio path signal is one of the following:

[0182] A first audio path signal, which is a source audio signal; or

[0183] A second audio path signal, which is a source audio signal processed by an intelligent filtering module; or

[0184] The third audio path signal is the source audio signal processed by the intelligent filtering module and the feedback filtering module.

[0185] In some embodiments of the present application, the second calculation unit 920 is specifically used to obtain the second transfer function G based on the frequency response SmartEQ of the smart filtering module and the frequency response FBEQ of the feedback filtering module when the audio path signal selects the first audio path signal; when the audio path signal selects the second audio path signal, the second transfer function G is obtained based on the frequency response FBEQ of the feedback filtering module; when the audio path signal selects the third audio path signal, the second transfer function G is obtained using the first transfer function and the frequency response Hb of the feedback noise reduction filter.

[0186] In some embodiments of the present application, the device 900 further includes a second stability judgment unit, configured to, after determining a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal, perform stability judgment on the first transfer function TF, and determine a stability judgment result of the first transfer function TF, wherein the stability judgment result includes that the first transfer function TF is stable or that the first transfer function TF is unstable;

[0187] The second calculation unit 920 is specifically configured to obtain a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter when the first transfer function TF is stable.

[0188] In some embodiments of the present application, the state detection unit 930 is specifically used to compensate the first transfer function TF based on the amplitude difference between the first transfer function TF and the second target transfer function TFd; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when the active noise reduction is turned off.

[0189] It can be understood that the above-mentioned noise-canceling headphone wearing state detection device can implement the various steps of the noise-canceling headphone wearing state detection method provided in the aforementioned embodiment, and the relevant explanations about the noise-canceling headphone wearing state detection method are applicable to the noise-canceling headphone wearing state detection device, which will not be repeated here.

[0190] like Fig.10As shown, a schematic structural diagram of an audio compensation device for a noise reduction headset in an embodiment of the present application is provided, wherein the noise reduction headset comprises a speaker located in a cavity formed by the headset and the ear canal and a feedback microphone arranged near the speaker, and the device 1000 comprises a third calculation unit 1100, a stability judgment unit 1200 and a first compensation unit 1300;

[0191] a third calculation unit 1100, configured to obtain an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal; the third calculation unit 1100 here may be the same functional unit as the first calculation unit 910 in the device 900;

[0192] A first stability judging unit 1200, configured to perform stability judging on the first transfer function TF;

[0193] The first compensation unit 1300 is used to compensate the first transfer function TF based on the amplitude difference between the first transfer function TF and a second target transfer function TFd when the first transfer function TF is stable; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when the active noise reduction is turned off.

[0194] In some embodiments of the present application, the audio path signal is one of the following:

[0195] A first audio path signal, which is a source audio signal; or

[0196] A second audio path signal, which is a source audio signal processed by an intelligent filtering module; or

[0197] The third audio path signal is the source audio signal processed by the intelligent filtering module and the feedback filtering module.

[0198] In some embodiments of the present application, the first compensation unit 1300 is specifically used to perform frequency band processing on the first transfer function TF to obtain multiple discontinuous sub-bands; obtain the amplitude difference between the first transfer function TF and the second target transfer function TFd in each sub-band; obtain the compensation gain and center frequency of each sub-band according to the amplitude difference of each sub-band; obtain the filter coefficient according to the compensation gain and center frequency of each sub-band, and obtain the compensation result of the first transfer function TF according to the filter coefficient and the first transfer function TF.

[0199] In some embodiments of the present application, the device 1000 also includes a second compensation unit, which is used to adjust the frequency response SmartEQ of the smart filtering module using the compensated first transfer function TF and the second target transfer function TFd, and use the adjusted smart filtering module to perform audio compensation on the noise reduction headphones.

[0200] It can be understood that the above-mentioned noise cancelling headphone audio compensation device can implement the various steps of the noise cancelling headphone audio compensation method provided in the aforementioned embodiment, and the relevant explanations about the noise cancelling headphone audio compensation method are applicable to the noise cancelling headphone audio compensation device, which will not be repeated here.

[0201] Fig.11 This is a schematic diagram of the structure of a noise reduction headset shown in an embodiment of the present application. Fig.11 At the hardware level, the electronic device includes a processor, and optionally also includes an internal bus, a network interface, and a memory. The memory may include a memory, such as a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage. Of course, the noise reduction headset may also include hardware required for other services, such as a feedback microphone, a speaker, a front feedback microphone, etc.

[0202] The processor, network interface and memory can be interconnected through an internal bus, which can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.11 Only one bidirectional arrow is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0203] The memory is used to store the program. Specifically, the program may include a program code, and the program code includes a computer operation instruction. The memory may include a memory and a non-volatile memory, and provides instructions and data to the processor.

[0204] The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it, forming a noise-canceling headphone wearing state detection device or a noise-canceling headphone audio compensation device at the logical level. The processor executes the program stored in the memory and executes the corresponding noise-canceling headphone wearing state detection method or noise-canceling headphone audio compensation method.

[0205] The above application Figure 3 The noise reduction headset wearing state detection method disclosed in the embodiment shown or Figure 7 The noise reduction headset audio compensation method disclosed in the illustrated embodiment can be applied to a processor or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor or instructions in the form of software. The above processor can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor for execution, or a combination of hardware and software modules in the decoding processor for execution. The software module can be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory, and the processor reads the information in the memory and completes the steps of the above-mentioned noise reduction headphone wearing state detection method or noise reduction headphone audio compensation method in combination with its hardware.

[0206] The noise cancelling headphones can also perform Figure 3 The method is executed by the noise reduction headphone wearing state detection device in the present invention, and the noise reduction headphone wearing state detection device is implemented in the present invention. Figure 3 The functions of the embodiments shown may also be performed Figure 7 The method is implemented by the noise reduction headset audio compensation device, and the noise reduction headset audio compensation device is implemented in Figure 7 The functions of the illustrated embodiment will not be described in detail in the embodiments of the present application.

[0207] The embodiment of the present application also provides a computer-readable storage medium, which stores one or more programs, wherein the one or more programs include instructions, which, when executed by a noise-canceling headset including a plurality of application programs, enable the noise-canceling headset to execute Figure 3 The method or execution performed by the noise reduction headset wearing state detection device in the embodiment shown in the figure Figure 7 The method performed by the noise reduction headphone audio compensation device in the illustrated embodiment.

[0208] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0209] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0210] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0211] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0212] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0213] The memory may include non-permanent storage in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0214] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0215] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0216] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0217] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method for detecting the wearing state of a noise-canceling headset, wherein the noise-canceling headset comprises a speaker located in a cavity formed by the noise-canceling headset and an ear canal and a feedback microphone arranged near the speaker, characterized in that: The noise reduction headphone wearing state detection method comprises: Acquire an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal; Obtaining a second transfer function G between the speaker and the feedback microphone using at least the first transfer function TF and a frequency response Hb of a feedback noise reduction filter; The wearing state of the noise reduction headset is detected according to the second transfer function G.

2. The method for detecting the wearing status of noise-cancelling headphones according to claim 1, characterized in that: The audio path signal is one of the following: A first audio path signal, which is a source audio signal; or A second audio path signal, which is a source audio signal processed by an intelligent filtering module; or The third audio path signal is the source audio signal processed by the intelligent filtering module and the feedback filtering module.

3. The method for detecting the wearing status of noise-cancelling headphones according to claim 2, characterized in that: The obtaining of a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter comprises: When the audio path signal selects the first audio path signal, the second transfer function G is also acquired based on the frequency response SmartEQ of the smart filter module and the frequency response FBEQ of the feedback filter module; When the audio path signal selects the second audio path signal, the second transfer function G is also obtained based on the frequency response FBEQ of the feedback filter module; When the audio path signal selects the third audio path signal, the second transfer function G is obtained by using the first transfer function and the frequency response Hb of the feedback noise reduction filter.

4. The method for detecting the wearing status of a noise-cancelling headphone according to any one of claims 1 to 3, characterized in that: After determining a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal, the method further comprises: Performing stability judgment on the first transfer function TF to determine a stability judgment result of the first transfer function TF, wherein the stability judgment result includes that the first transfer function TF is stable or the first transfer function TF is unstable; When the first transfer function TF is stable, a second transfer function G between the speaker and the feedback microphone is obtained by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter.

5. The method for detecting the wearing state of noise-cancelling headphones according to claim 2, characterized in that: The method further comprises: The first transfer function TF is compensated based on the amplitude difference between the first transfer function TF and the second target transfer function TFd; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when the active noise reduction is turned off.

6. A method for compensating audio of a noise-canceling headset, the noise-canceling headset comprising a speaker in a cavity formed by the headset and the ear canal and a feedback microphone disposed near the speaker, characterized in that: The noise reduction headphone audio compensation method comprises: Acquire an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal; Performing stability judgment on the first transfer function TF; When the first transfer function TF is stable, the first transfer function TF is compensated based on the amplitude difference between the first transfer function TF and a second target transfer function TFd; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when active noise reduction is turned off.

7. The noise reduction headphone audio compensation method according to claim 6, characterized in that: When the first transfer function TF is stable, compensating the first transfer function TF based on the amplitude difference between the first transfer function TF and the second target transfer function TFd comprises: Performing frequency band processing on the first transfer function TF to obtain a plurality of discontinuous sub-frequency bands; Obtaining the amplitude difference between the first transfer function TF and the second target transfer function TFd in each sub-frequency band; Obtaining a compensation gain and a center frequency of each sub-frequency band according to the amplitude difference of each sub-frequency band; A filter coefficient is obtained according to the compensation gain and the center frequency of each sub-band, and a compensation result of the first transfer function TF is obtained according to the filter coefficient and the first transfer function TF.

8. The noise reduction headphone audio compensation method according to claim 6, characterized in that: After compensating the first transfer function TF, the method further comprises: The frequency response SmartEQ of the smart filter module is adjusted by using the compensated first transfer function TF and the second target transfer function TFd, and the adjusted smart filter module is used to perform audio compensation on the noise reduction headset.

9. A device for detecting the wearing state of a noise-canceling headset, the noise-canceling headset comprising a speaker located in a cavity formed by the noise-canceling headset and an ear canal and a feedback microphone arranged near the speaker, characterized in that: The noise reduction headphone wearing state detection device comprises: a first calculation unit, configured to obtain an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal; A second calculation unit, configured to obtain a second transfer function G between the speaker and the feedback microphone by at least using the first transfer function TF and a frequency response Hb of a feedback noise reduction filter; A state detection unit is used to detect the wearing state of the noise reduction headset according to the second transfer function G.

10. An audio compensation device for a noise-canceling headset, the noise-canceling headset comprising a speaker in a cavity formed by the headset and the ear canal and a feedback microphone arranged near the speaker, characterized in that: The noise reduction headphone audio compensation device comprises: a third calculation unit, configured to obtain an audio path signal and a feedback audio signal collected by the feedback microphone, and determine a first transfer function TF between the audio path and the feedback microphone according to the audio path signal and the feedback audio signal; a first stability judgment unit, configured to perform stability judgment on the first transfer function TF; A first compensation unit is configured to compensate the first transfer function TF based on an amplitude difference between the first transfer function TF and a second target transfer function TFd when the first transfer function TF is stable; wherein the second target transfer function TFd is a transfer function from the audio path to the feedback microphone obtained when active noise reduction is turned off.

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