WO2022017424A1 - Active noise control method and apparatus, and audio playback device - Google Patents
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- WO2022017424A1 WO2022017424A1 PCT/CN2021/107685 CN2021107685W WO2022017424A1 WO 2022017424 A1 WO2022017424 A1 WO 2022017424A1 CN 2021107685 W CN2021107685 W CN 2021107685W WO 2022017424 A1 WO2022017424 A1 WO 2022017424A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
- H04R1/1083—Reduction of ambient noise
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/16—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
- G10K11/175—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound
- G10K11/178—Methods or devices for protecting against, or for damping, noise or other acoustic waves in general using interference effects; Masking sound by electro-acoustically regenerating the original acoustic waves in anti-phase
- G10K11/1785—Methods, e.g. algorithms; Devices
- G10K11/17853—Methods, e.g. algorithms; Devices of the filter
- G10K11/17854—Methods, e.g. algorithms; Devices of the filter the filter being an adaptive filter
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS TECHNIQUES OR SPEECH SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING TECHNIQUES; SPEECH OR AUDIO CODING OR DECODING
- G10L21/00—Speech or voice signal processing techniques to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
- G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
- G10L21/0208—Noise filtering
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
Definitions
- the present application relates to the field of active noise reduction technology, in particular to the active noise reduction technology for earphones. And more particularly, it relates to an active noise reduction method and device and an audio playback device in the field of active noise reduction technology.
- Active noise control is a noise reduction technology and one of the methods used in earphone noise reduction.
- the active noise reduction function refers to the generation of reverse sound waves equal to the external noise through the noise reduction system to neutralize the noise, thereby achieving the effect of noise reduction.
- the basic principle of active noise reduction is to calculate the reverse phase sound wave of the reference signal at the fastest speed based on the reference signal collected by the reference microphone set outside the headset and/or the error signal collected by the error microphone set inside the headset. , and then control the speaker to play the reverse sound wave to achieve the effect of active noise reduction. Therefore, it is calculated that the lower the time delay of the anti-phase sound wave is, the better the effect of active noise reduction is, otherwise it is easy to have an adverse effect.
- the time required to calculate the inverse sound waves is also different.
- the higher the audio frequency the shorter the time required to calculate the reverse sound wave, even in the sub-millisecond level. Therefore, the existing active noise reduction system has poor noise reduction effect on high frequency noise.
- the active noise reduction method and device and the audio playback device provided by the embodiments of the present application can improve the noise reduction effect on high frequency noise.
- inventions of the present application provide a composite active noise reduction system.
- the system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system may include a reference sensor (eg, a reference microphone), an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first pre-emphasis module, a second pre-emphasis module, a control module, and De-emphasis module.
- the reference sensor is connected to the first input terminal of the control module through the first pre-emphasis module
- the error sensor is connected to the second input terminal of the control module through the second pre-emphasis module
- the speaker is connected to the control module through the de-emphasis module.
- the output of the control module is connected.
- the reference sensor is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first pre-emphasis module.
- the first pre-emphasis module is configured to receive the first reference signal x(n) from the reference sensor; perform pre-emphasis processing on the first reference signal x(n) to obtain the target reference signal x 1 (n);
- the first input terminal of the control module sends the target reference signal x 1 (n).
- the frequency energy of the high frequency part of the pre-emphasized signal is higher than the frequency energy of the high frequency part of the original signal, that is to say, the resolution of the high frequency part of the pre-emphasized signal higher than the resolution of the high frequency portion of the original signal. Therefore, the high-frequency resolution of the signal processed by the control module can be improved, thereby improving the noise reduction effect of high-frequency noise.
- the high frequency part can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the first frequency band whose cutoff frequency is less than the frequency threshold. two frequency bands.
- the first frequency threshold may be 4000 Hz
- the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part
- the part whose frequency is less than 4000 Hz is called the low frequency part.
- the function implemented by the first pre-emphasis module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the first pre-emphasis module may include a first pre-emphasis circuit, and the first pre-emphasis circuit is configured to implement the function of the first pre-emphasis module.
- the error sensor is used to collect residual noise inside the earphone to obtain a first error signal e(n); and send the first error signal e(n) to the second pre-emphasis module.
- the second pre-emphasis module is configured to receive the first error signal e(n) from the error sensor; perform pre-emphasis processing on the first error signal e(n) to obtain the target error signal e 1 (n); A second input of the control module sends the target error signal e 1 (n).
- the control module is configured to receive the target reference signal x 1 (n) from the first pre-emphasis module and the target error signal e 1 (n) from the second pre-emphasis module; according to the target error signal e 1 ( n), perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); send the first output signal y(n) to the de-emphasis module.
- control module may include an adaptive filter.
- the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter.
- the structure of the adaptive filter is not changed.
- the coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response.
- the most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
- control module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- control module may include a control circuit, and the control circuit is used to implement the function of the control module.
- the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
- the adaptive filter may use a minimum mean square error algorithm.
- the de-emphasis module is used to receive the first output signal y(n) from the control module; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); send it to the speaker The target output signal y 1 (n).
- the function implemented by the de-emphasis module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the de-emphasis module may include a de-emphasis circuit, and the de-emphasis circuit is used to implement the function of the de-emphasis module.
- the speaker is used for receiving the target output signal y 1 (n) from the de-emphasis module; playing the target output signal y 1 (n).
- the resolution of the first reference signal and the high frequency part of the first error signal is improved by the pre-emphasis module, and then input to the control module for adaptive filtering, and the control module is restored by the de-emphasis module Output the resolution of the high frequency part of the first output signal, and control the speaker to play. That is to say, in the active noise reduction system provided by the embodiments of the present application, the pre-emphasis module and the de-emphasis module improve the high-frequency resolution of the signal processed by the control module, thereby improving the noise reduction effect on high-frequency noise.
- the embodiments of the present application further provide a feedforward active noise reduction system.
- the system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system may include a reference sensor (eg, a reference microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first pre-emphasis module control module and a de-emphasis module.
- the reference sensor is connected to the first input end of the control module through the first pre-emphasis module, and the speaker is connected to the output end of the control module through the de-emphasis module.
- the reference sensor is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first pre-emphasis module.
- the first pre-emphasis module is configured to receive the first reference signal x(n) from the reference sensor; perform pre-emphasis processing on the first reference signal x(n) to obtain the target reference signal x 1 (n);
- the first input terminal of the control module sends the target reference signal x 1 (n).
- the control module is configured to receive the target reference signal x 1 (n) from the first pre-emphasis module; perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); The first output signal y(n) is sent to the de-emphasis module.
- the de-emphasis module is used to receive the first output signal y(n) from the control module; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); send it to the speaker The target output signal y 1 (n).
- the speaker is used for receiving the target output signal y 1 (n) from the de-emphasis module; playing the target output signal y 1 (n).
- the embodiments of the present application further provide a feedback active noise reduction system.
- the system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system may include an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a second pre-emphasis module, a control module, and a de-emphasis module.
- the error sensor is connected to the second input end of the control module through the second pre-emphasis module, and the speaker is connected to the output end of the control module through the de-emphasis module.
- the error sensor is used to collect residual noise inside the earphone to obtain a first error signal e(n); and send the first error signal e(n) to the second pre-emphasis module.
- the second pre-emphasis module is configured to receive the first error signal e(n) from the error sensor; perform pre-emphasis processing on the first error signal e(n) to obtain the target error signal e 1 (n); A second input of the control module sends the target error signal e 1 (n).
- the control module is configured to receive the target error signal e 1 (n) from the second pre-emphasis module; perform adaptive filtering processing according to the target error signal e 1 (n) to obtain a first output signal y(n); The first output signal y(n) is sent to the de-emphasis module.
- the de-emphasis module is used to receive the first output signal y(n) from the control module; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); send it to the speaker The target output signal y 1 (n).
- the speaker is used for receiving the target output signal y 1 (n) from the de-emphasis module; playing the target output signal y 1 (n).
- inventions of the present application provide a composite active noise reduction system.
- the system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system may include a reference sensor (eg, a reference microphone), an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first low-pass filtering module, a second low-pass filtering module, a control modules and bandwidth extension modules.
- the reference sensor is connected to the first input end of the control module through the first low-pass filter module, the error sensor is connected to the second input end of the control module through the second low-pass filter module, and the speaker is connected to the second input end of the control module through the second low-pass filter module.
- the output terminals of the control module are connected.
- the reference sensor is used for collecting ambient noise outside the earphone to obtain a first reference signal x(n); and sending the first reference signal x(n) to the first low-pass filtering module.
- the first low-pass filtering module is configured to receive a first reference signal x(n) from the reference sensor; perform low-pass filtering processing on the first reference signal x(n) to obtain a target reference signal x 1 (n);
- the target reference signal x 1 (n) is sent to the first input of the control module.
- the low-pass filtering signal has filtered out the high-frequency part in the original signal, and only contains the low-frequency part with higher stability. Therefore, the high-frequency stability and robustness of the signal processed by the control module can be improved, thereby improving the noise reduction effect of high-frequency noise.
- the high frequency part can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the first frequency band whose cutoff frequency is less than the frequency threshold. two frequency bands.
- the first frequency threshold may be 4000 Hz
- the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part
- the part whose frequency is less than 4000 Hz is called the low frequency part.
- the first low-pass filtering module is specifically configured to downsample the first reference signal x(n) to obtain the target reference signal x 1 (n).
- the first low-pass filtering module is specifically used to extract an audio sampling point for every four audio sampling points to obtain the down-sampled x 1 (n), whose frequency width is is 1kHz bandwidth.
- the function implemented by the first low-pass filtering module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the first low-pass filtering module may include a first low-pass filtering circuit, and the first low-pass filtering circuit is configured to implement the function of the first low-pass filtering module.
- the error sensor is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second low-pass filtering module.
- the second low-pass filtering module is configured to receive the first error signal e(n) from the error sensor; perform low-pass filtering processing on the first error signal e(n) to obtain the target error signal e 1 (n); The target error signal e 1 (n) is sent to a second input of the control module.
- the function implemented by the second low-pass filtering module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the second low-pass filtering module may include a second low-pass filtering circuit, and the second low-pass filtering circuit is configured to implement the function of the second low-pass filtering module.
- the control module is configured to receive the target reference signal x 1 (n) from the first low-pass filtering module and the target error signal e 1 (n) from the second low-pass filtering module; according to the target error signal e 1 (n), perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); send the first output signal y(n) to the target reference signal y(n).
- control module may include an adaptive filter.
- the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter.
- the structure of the adaptive filter is not changed.
- the coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response.
- the most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
- control module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- control module may include a control circuit, and the control circuit is used to implement the function of the control module.
- the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
- the adaptive filter may use a minimum mean square error algorithm.
- the bandwidth expansion module is used for receiving the first output signal y(n) from the control module; performing bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); sending it to the speaker The target output signal y 1 (n).
- the bandwidth expansion module may perform bandwidth expansion processing on the first output signal in various manners to obtain the target output signal, which is not limited in this embodiment of the present application.
- the bandwidth expansion module may perform bandwidth expansion processing on the first output signal through a blind high-frequency reconstruction method to obtain the target output signal.
- the blind high-frequency reconstruction method may include: linear extrapolation (LE), efficient high-frequency bandwidth extension (EHBE), hybrid signal extrapolation (HSE) and nonlinear prediction.
- L linear extrapolation
- EHBE efficient high-frequency bandwidth extension
- HSE hybrid signal extrapolation
- the linear extrapolation method means that the logarithmic amplitude spectral envelope of the audio signal is in an approximately linearly decreasing relationship to perform high-frequency reconstruction, wherein the high-frequency reconstruction includes the frequency domain envelope of the high-frequency part and the spectral details of the high-frequency part. two parts. Among them, the high spectral envelope can be obtained by the linear relationship of the amplitude spectrum, and the high spectral details can be obtained by replicating the harmonic structure of the low frequency band.
- the bandwidth expansion module is specifically used to perform time-frequency transformation on the low-frequency signal y(n) to obtain its spectral envelope; use the linear least squares method to fit the envelope into a logarithmic domain straight line to obtain the best slope and intercept of the straight line; copy the spectral information of the low-frequency part to obtain the spectral details of the high-frequency part; use the slope of the fitted straight line to perform envelope attenuation on the high-frequency spectral details to complete the reconstruction of the high-frequency part , so as to obtain a complete signal y 1 (n) including high frequency part and low frequency part.
- the function implemented by the bandwidth expansion module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the bandwidth extension module may include a bandwidth extension circuit, and the bandwidth extension circuit is configured to implement the function of the bandwidth extension module.
- the speaker is used for receiving the target output signal y 1 (n) from the bandwidth expansion module; playing the target output signal y 1 (n).
- the first low-pass filtering module filters out the high-frequency part with poor stability in the first reference signal and/or the second low-pass filtering module filters out the first error signal.
- the control module for adaptive filtering, and the first reference signal output by the control module is reconstructed through the bandwidth expansion module.
- a high-frequency part of an output signal obtain a target output signal with a complete bandwidth (including both high-frequency part and low-frequency part), and control the speaker to play. That is, the stability and robustness of the high-frequency part of the signal processed by the control module are improved through the low-pass filtering module and the bandwidth expansion module, thereby improving the noise reduction effect of high-frequency noise.
- the embodiments of the present application further provide a feedforward active noise reduction system.
- the system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system may include a reference sensor (eg, a reference microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first low-pass filtering module, a control module, and a bandwidth expansion module.
- the reference sensor is connected to the first input end of the control module through the first low-pass filter module, and the speaker is connected to the output end of the control module through this.
- the reference sensor is used for collecting ambient noise outside the earphone to obtain a first reference signal x(n); and sending the first reference signal x(n) to the first low-pass filtering module.
- the first low-pass filtering module is configured to receive a first reference signal x(n) from the reference sensor; perform low-pass filtering processing on the first reference signal x(n) to obtain a target reference signal x 1 (n);
- the target reference signal x 1 (n) is sent to the first input of the control module.
- the control module is configured to receive the target reference signal x 1 (n) from the first low-pass filtering module; perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n) ; send the first output signal y(n) to this.
- the bandwidth expansion module is used for receiving the first output signal y(n) from the control module; performing bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); sending it to the speaker The target output signal y 1 (n).
- the speaker is used for receiving the target output signal y 1 (n) from the bandwidth expansion module; playing the target output signal y 1 (n).
- an embodiment of the present application provides a feedback active noise reduction system.
- the system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system may include an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a second low-pass filter module, a control module, and a bandwidth expansion module.
- the error sensor is connected to the second input end of the control module through the second low-pass filter module, and the speaker is connected to the output end of the control module through the second low-pass filter module.
- the error sensor is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second low-pass filtering module.
- the second low-pass filtering module is configured to receive the first error signal e(n) from the error sensor; perform low-pass filtering processing on the first error signal e(n) to obtain the target error signal e 1 (n); The target error signal e 1 (n) is sent to a second input of the control module.
- the control module is configured to receive the target error signal e 1 (n) from the second low-pass filtering module; perform adaptive filtering processing according to the target error signal e 1 (n) to obtain a first output signal y(n) ; send the first output signal y(n) to this.
- the bandwidth expansion module is used for receiving the first output signal y(n) from the control module; performing bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); sending it to the speaker The target output signal y 1 (n).
- the speaker is used for receiving the target output signal y 1 (n) from the bandwidth expansion module; playing the target output signal y 1 (n).
- the embodiments of the present application further provide an active noise reduction method, and the method may include the methods performed by the active noise reduction apparatus in the above aspects or various possible implementation manners thereof.
- an embodiment of the present application further provides an active noise reduction device, the device includes: a memory, at least one processor, a transceiver, and instructions stored on the memory and executable on the processor. Further, the memory, the processor and the communication interface communicate with each other through an internal connection path. Execution of the instructions by the at least one processor causes the apparatus to implement the method performed by the active noise reduction apparatus in the aspects or any possible implementations thereof.
- the present application further provides a computer-readable storage medium for storing a computer program, the computer program including a method for implementing the above-mentioned first aspect or any possible implementation manners thereof and executed by an active noise reduction apparatus.
- the present application also provides a computer program product comprising instructions, which, when run on a computer, enable the computer to implement the method performed by the active noise reduction device in each of the above aspects or any possible implementations thereof.
- the present application further provides a chip device, including: an input interface, an output interface, and at least one processor.
- the chip device further includes a memory.
- the at least one processor is configured to execute the code in the memory, and when the at least one processor executes the code, the chip device implements the method performed by the active noise reduction apparatus in the above-mentioned various aspects or any possible implementation manners thereof.
- FIG. 1 is a schematic diagram of an active noise reduction principle provided by an embodiment of the present application.
- FIG. 2 is a schematic diagram of a scene of a feedforward active noise reduction system provided by an embodiment of the present application
- FIG. 3 is a schematic diagram of the principle of a feedforward active noise reduction system provided by an embodiment of the present application.
- FIG. 4 is a schematic diagram of a scene of a feedback active noise reduction system provided by an embodiment of the present application.
- FIG. 5 is a schematic diagram of the principle of a feedback active noise reduction system provided by an embodiment of the present application.
- FIG. 6 is a schematic diagram of a scene of a composite active noise reduction system provided by an embodiment of the present application.
- FIG. 7 is a schematic diagram of the principle of a composite active noise reduction system provided by an embodiment of the present application.
- FIG. 8 is a schematic diagram of an application scenario provided by an embodiment of the present application.
- FIG. 9 is a schematic diagram of another application scenario provided by an embodiment of the present application.
- FIG. 10 is a schematic diagram of another application scenario provided by an embodiment of the present application.
- FIG. 11 is a schematic diagram of another application scenario provided by an embodiment of the present application.
- FIG. 12 is a schematic diagram of another application scenario provided by an embodiment of the present application.
- FIG. 13 is a schematic diagram of another application scenario provided by an embodiment of the present application.
- FIG. 14 is a schematic block diagram of an active noise reduction system 500 provided by an embodiment of the present application.
- 15 is a schematic diagram of a spectrum of pre-emphasis processing provided by an embodiment of the present application.
- FIG. 16 is a schematic block diagram of another active noise reduction system 500 provided by an embodiment of the present application.
- FIG. 17 is a schematic block diagram of another active noise reduction system 500 provided by an embodiment of the present application.
- FIG. 18 is a schematic block diagram of an active noise reduction system 600 provided by an embodiment of the present application.
- 19 is a schematic diagram of a spectrum of low-pass filtering processing provided by an embodiment of the present application.
- FIG. 20 is a schematic block diagram of another active noise reduction system 600 provided by an embodiment of the present application.
- FIG. 21 is a schematic block diagram of another active noise reduction system 600 provided by an embodiment of the present application.
- FIG. 22 is a schematic flowchart of an active noise reduction method 700 provided by an embodiment of the present application.
- FIG. 23 is a schematic flowchart of another active noise reduction method 800 provided by an embodiment of the present application.
- FIG. 24 is a schematic block diagram of an active noise reduction apparatus 900 provided by an embodiment of the present application.
- FIG. 25 is a schematic block diagram of an active noise reduction apparatus 1000 provided by an embodiment of the present application.
- FIG. 26 is a schematic block diagram of a chip 1100 provided by an embodiment of the present application.
- Active noise reduction is a noise control technique that attenuates initial noise by referencing sound waves from a secondary sound source that have the same amplitude and opposite phase as the primary sound source, and the output of the secondary sound source is used to interfere with the primary sound source. (noise source), as shown in Figure 1.
- control circuit classification it can include: analog and digital.
- control structure classification it can include: feed forward, feedback and compound.
- the feedforward active noise cancellation system may include a reference sensor (such as a reference microphone) deployed outside the earphone, a controller deployed inside the earphone, and speaker.
- a reference sensor such as a reference microphone
- controller deployed inside the earphone
- speaker The connection relationship among the controller, the reference sensor and the speaker is shown in FIG. 3 .
- the reference sensor is used to collect ambient noise outside the earphone (such as the primary noise or noise source in Figure 1), to obtain a reference signal x(n), and input the x(n) to the controller, and the controller is used for the x(n) (n) Invert the phase to obtain the output signal y(n) (the secondary noise in Figure 1), the output signal y(n) is opposite to the phase of the noise source, and the speaker is used to play the output signal y(n) ) to achieve noise reduction of the noise source.
- the outside of the earphone described in the embodiments of the present application can be understood as the side of the earphone that is far away from the human ear, and the inside of the earphone can be understood as the side of the earphone that is close to the human ear.
- the feedback active noise cancellation system may include an error sensor (eg, an error microphone), a controller, and a speaker deployed inside the headset.
- an error sensor eg, an error microphone
- controller e.g., a controller
- speaker deployed inside the headset.
- FIG. 5 The connection relationship among the controller, the error sensor and the speaker is shown in FIG. 5 .
- the error sensor is used to collect the residual noise inside the earphone (such as the residual noise in Figure 1) to obtain the error signal e(n), and the e(n) is input to the controller, and the controller is used for according to the e(n) Perform adaptive filtering to obtain an output signal y(n) (secondary noise in Figure 1), the output signal y(n) is opposite to the phase of the noise source, and the speaker is used to play the output signal y(n), It is a closed-loop process to minimize e(n) obtained after y(n) is superimposed with the noise source.
- the feedback active noise reduction system may include a reference sensor (such as a reference microphone) deployed outside the earphone, an error sensor (such as a reference microphone) deployed inside the earphone such as error microphones), controllers and speakers.
- a reference sensor such as a reference microphone
- an error sensor such as a reference microphone deployed inside the earphone such as error microphones
- controllers and speakers.
- the connection relationship among the controller, the reference sensor, the error sensor and the speaker is shown in FIG. 7 .
- the reference sensor is used to collect the ambient noise outside the earphone (such as the primary noise or noise source in Figure 1), and the obtained reference signal x(n) is input to the controller, and the error microphone collects the inside of the earphone.
- the residual noise (residual noise in Figure 1) is obtained, the error signal e(n) is obtained, the e(n) is input to the controller, the controller according to the e(n), the x(n) is automatically Adaptive filtering to obtain an output signal y(n) (secondary noise in Figure 1), the output signal y(n) is opposite to the phase of the noise source, and the output signal y(n) is played through the speaker so that y(n ) and the noise source are superimposed to obtain the smallest e(n).
- the active noise reduction method provided by the embodiment of the present application can be applied to an audio playback device.
- the audio playback device described in this embodiment of the present application refers to an audio playback device worn on or near the ear by the user, which may include earphones, wearable smart devices, and the like, which are not limited in this embodiment of the present application.
- the audio playback device when it is an earphone, it may include an in-ear earphone, a headphone, etc. according to the wearing method; and may include: wired earphones, wireless earphones, such as Bluetooth earphones, etc. according to the connection method.
- the wearable smart device may include augmented reality (AR)/virtual reality (VR) devices, such as AR/VR helmets, AR/VR VR masks, AR/VR glasses, etc.
- AR augmented reality
- VR virtual reality
- the audio playback device may implement the audio playback function without relying on an intelligent terminal (such as a smart phone), or may need to be used in conjunction with an intelligent terminal (such as a smart phone) to implement the audio playback function, which is not limited in this embodiment of the present application.
- the active noise reduction system provided in the embodiment of the present application may be applicable to various scenarios that require the noise reduction function of an audio playback device, such as: an active noise reduction scenario of answering a phone call, video call, playing audio or video, etc., This embodiment of the present application does not limit this.
- the audio playback device as an earphone as an example to introduce the applicable scene of the active noise reduction method provided by the embodiment of the present application, but the embodiment of the present application is not limited thereto.
- the audio playback device is a wearable device
- the applicable scene of the active noise reduction method is similar to that of an earphone, and in order to avoid repetition, details are not repeated here.
- a trigger condition for triggering the active noise reduction instruction may be set on the earphone, and when the user wants to enable the active noise reduction function, the earphone can be operated to trigger the active noise reduction instruction of the earphone.
- the trigger condition for triggering the active noise reduction instruction may be set in various ways, which is not limited in this embodiment of the present application.
- a physical button or the like that triggers active noise reduction may be provided on the earphone or the wire control of the earphone.
- the gesture recognition instruction can be triggered.
- the in-ear headphone 100 may include a physical button 101 , and the physical button 101 is a noise reduction button.
- the user can press the physical button 101 with a finger to trigger an active noise reduction instruction and enable the active noise reduction function.
- the in-ear headphone 100 shown in FIG. 8 may also be the headphone 100 shown in FIG. 9 or the Bluetooth wireless headphone 100 shown in FIG. 10 , which is not limited in this embodiment of the present application.
- the in-ear wire-controlled headset 200 may include an earphone 210 and a wire-controlled device 220, and the wire-controlled device may include a physical button 221 and a physical button 222, where the physical button 221 is a volume button, and the physical button 222 is for answering /hang up key.
- the user needs to use the noise reduction function of the headset, press the first side and the second side of the volume key with two fingers at the same time to trigger the active noise reduction command and enable the active noise reduction function.
- the headset when the headset relies on a terminal connected to it and capable of performing playback control to implement the active noise reduction function, the terminal may be provided with a virtual key for triggering active noise reduction.
- the active noise reduction instruction can be triggered, and the headset can be controlled to realize the active noise reduction function.
- the foregoing headset and the terminal may be connected in a wired or wireless manner, which is not limited in this embodiment of the present application.
- the terminal described in the embodiments of the present application may be able to cooperate with the audio playback device to use a mobile phone, a tablet computer, a wearable device, a vehicle-mounted device, a smart TV, a notebook computer, a super mobile personal computer ( Ultra-mobile personal computer, UMPC), netbook, personal digital assistant (personal digital assistant, PDA) and other devices, the embodiment of the present application does not impose any restrictions on the specific type of the terminal.
- Ultra-mobile personal computer, UMPC Ultra-mobile personal computer
- PDA personal digital assistant
- the setting options of the mobile phone 300 may include an “ANC” option 301.
- the display will display In the interface shown in (b) of FIG. 12 , the “ON” option 302 is used to enable the ANC function, and the “OFF” option 303 is used to disable the ANC function, then when the user selects the “ON” option 302 , the mobile phone 300 can control the headset connected to it to activate the corresponding active noise reduction function to play audio.
- the terminal may set the association between certain applications and the active noise reduction command.
- the active noise cancellation command is automatically triggered, and the headset is controlled to implement the active noise cancellation function.
- the user can set the association between the audio software and the active noise reduction instruction on the mobile phone.
- the terminal 400 displays that the default song list of the audio software includes A song 401 and B song 402 .
- the user clicks the B song 402 starts the audio software to play the B song 402, and the B song 402 automatically triggers the active noise reduction command when the audio software starts, and the mobile phone 400 can control the headset connected to it to start the corresponding active noise reduction function for audio playback.
- FIG. 14 is a schematic block diagram of an active noise reduction system 500 provided by an embodiment of the present application.
- the system 500 can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system 500 may include a reference sensor 510 (eg, a reference microphone), an error sensor 520 (eg, an error microphone), a speaker 530 and an active noise reduction device 540 , wherein the active noise reduction device 540 includes a first A pre-emphasis module 541 , a second pre-emphasis module 542 , a control module 543 and a de-emphasis module 544 .
- the reference sensor 510 is connected to the first input end of the control module 543 through the first pre-emphasis module 541 , the error sensor 520 is connected to the second input end of the control module 543 through the second pre-emphasis module 542 , the speaker 530 is connected to the output end of the control module 543 through the de-emphasis module 544 .
- the reference sensor 510 the error sensor 520 , the speaker 530 and the active noise reduction device 540 .
- the reference sensor 510 is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first pre-emphasis module 541 .
- the first pre-emphasis module 541 is configured to receive the first reference signal x(n) from the reference sensor 510; perform pre-emphasis processing on the first reference signal x(n) to obtain the target reference signal x 1 (n);
- the target reference signal x 1 (n) is sent to the first input of the control module 543 .
- FIG. 15 shows a schematic diagram of the spectrum of the pre-emphasis process. It can be seen from FIG. 15 that the frequency point energy of the high-frequency part of the pre-emphasized signal is higher than that of the original signal. Part of the frequency bin energy, that is, the resolution of the high-frequency part of the pre-emphasized signal is higher than the resolution of the high-frequency part of the original signal. Therefore, the high-frequency resolution of the signal processed by the control module 543 can be improved, thereby improving the noise reduction effect of high-frequency noise.
- the high frequency part described in the embodiments of the present application can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the cutoff frequency less than the frequency threshold. second frequency band.
- the first frequency threshold may be 4000 Hz
- the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part
- the part whose frequency is less than 4000 Hz is called the low frequency part.
- the first pre-emphasis module 541 may perform pre-emphasis processing on the first reference noise reduction signal x(n) according to the following formula 1 to obtain the target reference noise reduction signal x 1 (n).
- x(n) represents the sampled value at the nth time
- x(n-1) represents the sampled value at the n-1th time
- x 1 (n) represents the pre-emphasized sampled value at the nth time
- a represents The weighting factor is 0.9 ⁇ a ⁇ 1.
- the function implemented by the first pre-emphasis module 541 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the first pre-emphasis module 541 may include a first pre-emphasis circuit, and the first pre-emphasis circuit is used to implement the function of the first pre-emphasis module 541 .
- the error sensor 520 is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second pre-emphasis module 542 .
- the second pre-emphasis module 542 is configured to receive the first error signal e(n) from the error sensor 520; perform pre-emphasis processing on the first error signal e(n) to obtain the target error signal e 1 (n); The target error signal e 1 (n) is sent to the second input of the control module 543 .
- the second pre-emphasis module 542 may perform pre-emphasis processing on the first error noise reduction signal e(n) according to the following formula 2 to obtain the target error noise reduction signal e 1 (n).
- e(n) represents the sampled value at the nth time
- e(n-1) represents the sampled value at the n-1th time
- e 1 (n) represents the pre-emphasized sampled value at the nth time
- b represents The weighting factor is 0.9 ⁇ b ⁇ 1.
- the function implemented by the second pre-emphasis module 542 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the second pre-emphasis module 542 may include a second pre-emphasis circuit, and the second pre-emphasis circuit is configured to implement the function of the second pre-emphasis module 542 .
- the control module 543 is configured to receive the target reference signal x 1 (n) from the first pre-emphasis module 541 and the target error signal e 1 (n) from the second pre-emphasis module 542; according to the target error signal e 1 (n), perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); send the first output signal y(n) to the de-emphasis module 544 .
- control module 543 can perform adaptive filtering processing on the target reference signal x 1 (n) according to the target error signal e 1 (n) through the following formulas 3 to 5, to obtain The first output signal y(n).
- y 1 (n) represents the de-emphasized sample value at the nth time
- x 1 (n) represents the pre-emphasis sample value at the nth time
- e 1 (n) represents the pre-emphasis at the nth time.
- the sampled value after emphasis, d(n) represents the external noise signal (ie noise source) of the earphone
- w(n+1) represents the filter coefficient at the n+1th time
- w(n) represents the filter at the nth time coefficient
- c represents the convergence factor.
- control module 543 may include an adaptive filter.
- the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter.
- the structure of the adaptive filter is not changed.
- the coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response.
- the most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
- control module 543 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- control module 543 may include a control circuit, and the control circuit is used to implement the function of the control module 543 .
- the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
- the adaptive filter may use a minimum mean square error algorithm.
- the de-emphasis module 544 is configured to receive the first output signal y(n) from the control module 543; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); The speaker sends the target output signal y 1 (n).
- the de-emphasis module 544 may perform de-emphasis processing on the first output signal y(n) according to the following formula 6 to obtain the target output signal y 1 (n).
- y(n) represents the sampled value at the nth time
- y(n-1) represents the sampled value at the n-1th time
- y 1 (n) represents the de-emphasized sampled value at the nth time
- d represents the The aggravation factor, and 0.9 ⁇ d ⁇ 1.
- the function implemented by the de-emphasis module 544 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the de-emphasis module 544 may include a de-emphasis circuit, and the de-emphasis circuit is used to implement the function of the de-emphasis module 544 .
- the speaker 530 is used for receiving the target output signal y 1 (n) from the de-emphasis module 544; and playing the target output signal y 1 (n).
- the resolution of the first reference signal and the high-frequency part of the first error signal is improved through the pre-emphasis module, and then input to the control module for adaptive filtering, and the de-emphasis module restores the control module Output the resolution of the high frequency part of the first output signal, and control the speaker to play. That is to say, in the active noise reduction system provided by the embodiments of the present application, the pre-emphasis module and the de-emphasis module improve the high-frequency resolution of the signal processed by the control module, thereby improving the noise reduction effect on high-frequency noise.
- FIG. 14 only exemplifies the introduction of the active noise reduction system provided by the embodiment of the present application as a composite active noise reduction system, and the active noise reduction system may also be a feedforward type as shown in FIG. 16 .
- the active noise reduction system, or the feedback active noise reduction system as shown in FIG. 17 is not limited in this embodiment of the present application.
- the processing process of the active noise reduction system may refer to the composite active noise reduction described in FIG. 14 above.
- the processing process of the corresponding module in the noise system is not repeated here in order to avoid repetition.
- FIG. 18 is a schematic block diagram of an active noise reduction system 600 provided by an embodiment of the present application.
- the system 600 can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices.
- the system 500 may include a reference sensor 610 (eg, a reference microphone), an error sensor 620 (eg, an error microphone), a speaker 630 and an active noise reduction device 640 , wherein the active noise reduction device 640 includes a first A low-pass filtering module 641 , a second low-pass filtering module 642 , a control module 643 and a bandwidth expansion module 644 .
- the reference sensor 610 is connected to the first input terminal of the control module 643 through the first low-pass filter module 641 , the error sensor 620 is connected to the second input terminal of the control module 643 through the second low-pass filter module 642 ,
- the speaker 630 is connected to the output end of the control module 643 through the 644 .
- FIG. 6 For the arrangement positions and connection relationships of the reference sensor 610 , the error sensor 620 , the speaker 630 and the active noise reduction device 640 , reference may be made to FIG. 6 .
- the reference sensor 610 is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first low-pass filtering module 641 .
- the first low-pass filtering module 641 is configured to receive the first reference signal x(n) from the reference sensor 610; perform low-pass filtering on the first reference signal x(n) to obtain the target reference signal x 1 (n ); send the target reference signal x 1 (n) to the first input terminal of the control module 643 .
- FIG. 19 shows a schematic diagram of the frequency spectrum of the low-pass filtering process. It can be seen from FIG. 19 that the low-pass filtering signal has filtered out the high-frequency part in the original signal, and only contains stable The higher frequency low frequency part. Therefore, the high-frequency stability and robustness of the signal processed by the control module 543 can be improved, thereby improving the noise reduction effect of high-frequency noise.
- the high frequency part described in the embodiments of the present application can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the cutoff frequency less than the frequency threshold. second frequency band.
- the first frequency threshold may be 4000 Hz
- the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part
- the part whose frequency is less than 4000 Hz is called the low frequency part.
- the first low-pass filtering module 641 is specifically configured to downsample the first reference signal x(n) to obtain the target reference signal x 1 (n).
- the first low-pass filtering module 641 is specifically used to extract an audio sampling point for every four audio sampling points to obtain the down-sampled x 1 (n), whose frequency The width is 1kHz bandwidth.
- the function implemented by the first low-pass filtering module 641 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the first low-pass filtering module 641 may include a first low-pass filtering circuit, and the first low-pass filtering circuit is used to implement the function of the first low-pass filtering module 641 .
- the error sensor 620 is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second low-pass filtering module 642 .
- the second low-pass filtering module 642 is configured to receive the first error signal e(n) from the error sensor 620; perform low-pass filtering on the first error signal e(n) to obtain the target error signal e 1 (n ); send the target error signal e 1 (n) to the second input terminal of the control module 643 .
- the function implemented by the second low-pass filtering module 642 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the second low-pass filtering module 642 may include a second low-pass filtering circuit, and the second low-pass filtering circuit is used to implement the function of the second low-pass filtering module 642 .
- the control module 643 is configured to receive the target reference signal x 1 (n) from the first low-pass filtering module 641 and the target error signal e 1 (n) from the second low-pass filtering module 642; according to the target The error signal e 1 (n) is subjected to adaptive filtering processing on the target reference signal x 1 (n) to obtain the first output signal y(n); the first output signal y(n) is sent to the 644 .
- control module 643 may include an adaptive filter.
- the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter.
- the structure of the adaptive filter is not changed.
- the coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response.
- the most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
- control module 643 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- control module 643 may include a control circuit, and the control circuit is used to realize the function of the control module 643 .
- the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
- the adaptive filter may use a minimum mean square error algorithm.
- the bandwidth expansion module 644 is configured to receive the first output signal y(n) from the control module 643; perform bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); The speaker sends the target output signal y 1 (n).
- the bandwidth expansion module 644 may perform bandwidth expansion processing on the first output signal in various manners to obtain a target output signal, which is not limited in this embodiment of the present application.
- the bandwidth expansion module 644 may perform bandwidth expansion processing on the first output signal through a blind high-frequency reconstruction method to obtain the target output signal.
- the blind high-frequency reconstruction method may include: linear extrapolation (LE), efficient high-frequency bandwidth extension (EHBE), hybrid signal extrapolation (HSE) and nonlinear prediction.
- L linear extrapolation
- EHBE efficient high-frequency bandwidth extension
- HSE hybrid signal extrapolation
- the linear extrapolation method means that the logarithmic amplitude spectral envelope of the audio signal is in an approximately linearly decreasing relationship to perform high-frequency reconstruction, wherein the high-frequency reconstruction includes the frequency domain envelope of the high-frequency part and the spectral details of the high-frequency part. two parts. Among them, the high spectral envelope can be obtained by the linear relationship of the amplitude spectrum, and the high spectral details can be obtained by replicating the harmonic structure of the low frequency band.
- the bandwidth expansion module 644 is specifically configured to perform time-frequency transformation on the low-frequency signal y(n) to obtain its spectral envelope; use the linear least squares method to fit the envelope in the logarithmic domain as A straight line is used to obtain the best slope and intercept of the straight line; the spectral information of the low-frequency part is copied to obtain the spectral details of the high-frequency part; the envelope attenuation of the high-frequency spectral details is performed by the slope of the fitted straight line to complete the high-frequency part. Reconstruction to obtain a complete signal y 1 (n) including high frequency part and low frequency part.
- the function implemented by the bandwidth expansion module 644 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
- the bandwidth extension module 644 may include a bandwidth extension circuit, and the bandwidth extension circuit is used to implement the function of the bandwidth extension module 644 .
- the speaker 630 is used for receiving the target output signal y 1 (n) from the bandwidth expansion module 644; and playing the target output signal y 1 (n).
- the first low-pass filtering module filters out the high-frequency part with poor stability in the first reference signal and/or the second low-pass filtering module filters out the first error signal.
- the control module for adaptive filtering, and the first reference signal output by the control module is reconstructed through the bandwidth expansion module.
- a high-frequency part of an output signal obtain a target output signal with a complete bandwidth (including both high-frequency part and low-frequency part), and control the speaker to play. That is, the stability and robustness of the high-frequency part of the signal processed by the control module are improved through the low-pass filtering module and the bandwidth expansion module, thereby improving the noise reduction effect of high-frequency noise.
- FIG. 18 only exemplifies the introduction of the active noise reduction system provided by the embodiment of the present application as a composite active noise reduction system.
- the active noise reduction system may also be a feedforward type as shown in FIG. 20 .
- the active noise reduction system, or the feedback active noise reduction system as shown in FIG. 21 is not limited in this embodiment of the present application.
- the processing process of the active noise reduction system may refer to the composite active noise reduction described in FIG. 18 above.
- the processing process of the corresponding module in the noise system is not repeated here in order to avoid repetition.
- FIG. 22 shows a schematic flowchart of an active noise reduction method 700 provided by an embodiment of the present application.
- the method 700 can be applied to the composite active noise reduction system 500 as shown in FIG. 14 and executed by the active noise reduction device 540 in the system 500 .
- the method 700 may include the following S701-S707.
- S701 Acquire a first reference signal collected by a reference sensor, where the first reference signal is used to represent ambient noise outside the audio playback device.
- S702 Perform pre-emphasis processing on the first reference signal to obtain a target reference signal.
- S703 Acquire a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device.
- S705 Perform filtering processing on the target reference signal according to the target error signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal.
- the method 700 can also be applied to the feedforward active noise reduction system 500 shown in FIG. 16 , and executed by the active noise reduction device 540 in the system 500 .
- the method 700 includes the above-mentioned S701-S702 and S705-S707.
- S705 includes: filtering the target reference signal to obtain the first output signal.
- the method 700 can also be applied to the feedback active noise reduction system 500 as shown in FIG. 17 and executed by the active noise reduction device 540 in the system 500 .
- the method 700 includes the above-mentioned S703-S707.
- S705 includes: performing filtering processing according to the target error signal to obtain the first output signal.
- FIG. 23 shows a schematic flowchart of an active noise reduction method 800 provided by an embodiment of the present application.
- the method 800 can be applied to the composite active noise reduction system 600 as shown in FIG. 18 and executed by the active noise reduction device 640 in the system 600 .
- the method 800 may include the following S801-S807.
- S801 Acquire a first reference signal collected by a reference sensor, where the first reference signal is used to represent ambient noise outside the audio playback device.
- S802 Perform low-pass filtering on the first reference signal to obtain a target reference signal.
- S803 Acquire a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device.
- S804 Perform low-pass filtering on the first error signal to obtain a target error signal.
- the method 800 can also be applied to the feedforward active noise reduction system 600 as shown in FIG. 16 and executed by the active noise reduction device 640 in the system 600 .
- the method 800 includes the above-mentioned S801-S802 and S805-S807.
- S805 includes: filtering the target reference signal to obtain the first output signal.
- the method 800 can also be applied to the feedback active noise reduction system 600 as shown in FIG. 18 and executed by the active noise reduction device 640 in the system 600 .
- the method 800 includes the above-mentioned S803-S807.
- S805 includes: performing filtering processing according to the target error signal to obtain the first output signal.
- the active noise reduction method provided by the embodiments of the present application is described above with reference to FIGS. 22 and 23 , and the active noise reduction device 900 provided by the embodiments of the present application will be described below with reference to FIGS. 24 to 25 .
- apparatus 900 may be the active noise reduction apparatus described in the foregoing system 500 embodiment and the method 700 embodiment, or may be the active noise reduction apparatus described in the foregoing system 600 embodiment and method 800 embodiment. noise device, which is not limited in this embodiment of the present application.
- the apparatus 900 includes corresponding hardware and/or software modules for executing each function.
- the present application can be implemented in hardware or a combination of hardware and computer software in conjunction with the algorithm steps of the examples described in conjunction with the embodiments disclosed herein. Whether a function is performed by hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functionality for each particular application in conjunction with the embodiments, but such implementations should not be considered beyond the scope of this application.
- the apparatus 900 may be divided into functional modules according to the foregoing method examples.
- each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module.
- the above-mentioned integrated modules can be implemented in the form of hardware. It should be noted that, the division of modules in this embodiment is schematic, and is only a logical function division, and there may be other division manners in actual implementation.
- FIG. 24 shows a possible schematic diagram of the composition of the active noise reduction device involved in the above embodiments.
- the device 900 may include: unit 910 and processing unit 920.
- processing unit 920 may control the transceiver unit 910 to implement the method described in the foregoing method 700 embodiment or 800, and/or other processes for the techniques described herein.
- the apparatus 900 provided in this embodiment is used to execute the above-mentioned method 700 and/or the method 800, and thus can achieve the same effect as the above-mentioned implementation method.
- the apparatus 900 is an active noise reduction apparatus, and correspondingly, the processing unit 910 may include a first pre-emphasis module 541 and/or a second pre-emphasis module 542, a control module 543 and a de-emphasis module 544; Alternatively, the processing unit 310 may have a first low-pass filtering module 641 and/or a second low-pass filtering module 642 , a control module 643 and a bandwidth expansion module 644 .
- the apparatus 900 may include a processing unit, a storage unit, and a communication unit.
- the processing unit may be used to control and manage the actions of the apparatus 900, for example, may be used to support the apparatus 900 to perform the steps performed by the above-mentioned units.
- the storage unit may be used to support the execution of the apparatus 900 to store program codes, data, and the like.
- the communication unit may be used to support the communication of the apparatus 900 with other devices.
- the processing unit may be a processor or a controller. It may implement or execute the various exemplary logical blocks, modules and circuits described in connection with this disclosure.
- the processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, and the like.
- the storage unit may be a memory.
- the communication unit may specifically be a device that interacts with other electronic devices, such as a radio frequency circuit, a Bluetooth chip, and a Wi-Fi chip.
- the apparatus 900 involved in this embodiment may be an active noise reduction apparatus 1000 having the structure shown in FIG. 25
- the apparatus 1000 includes a processor 1010 and a transceiver 1020
- the processor 1010 and the transceiver The devices 1020 communicate with each other through internal connection paths.
- the related functions implemented by the processing unit 920 in FIG. 25 can be implemented by the processor 1010
- the related functions implemented by the transceiver unit 910 can be implemented by the processor 1010 controlling the transceiver 1020 .
- the apparatus 1000 may further include a memory 1030, and the processor 1010, the transceiver 1020 and the memory 1030 communicate with each other through an internal connection path.
- the related functions implemented by the storage unit described in FIG. 24 may be implemented by the memory 1030 .
- This embodiment also provides a computer storage medium, where computer instructions are stored in the computer storage medium, and when the computer instructions are executed on the electronic device, the electronic device executes the above-mentioned relevant method steps to realize the active noise reduction method in the above-mentioned embodiment. .
- This embodiment also provides a computer program product, which when the computer program product runs on the computer, causes the computer to execute the above-mentioned relevant steps, so as to realize the active noise reduction method in the above-mentioned embodiment.
- the embodiments of the present application also provide an apparatus, which may specifically be a chip, a component or a module, and the apparatus may include a connected processor and a memory; wherein, the memory is used to store computer execution instructions, and when the apparatus is running, The processor can execute the computer-executable instructions stored in the memory, so that the chip executes the active noise reduction method in the foregoing method embodiments.
- FIG. 26 shows a schematic structural diagram of a chip 1100 .
- Chip 1100 includes one or more processors 1110 and interface circuits 1120 .
- the chip 1100 may further include a bus 1130 . in:
- the processor 1110 may be an integrated circuit chip with signal processing capability. In the implementation process, each step of the above-mentioned method can be completed by an integrated logic circuit of hardware in the processor 1110 or an instruction in the form of software.
- the aforementioned processor 1110 may be a general purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware components. Various methods and steps disclosed in the embodiments of this application can be implemented or executed.
- a general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
- the interface circuit 1120 can be used for transmitting or receiving radar signals.
- the processor 1110 can process the radar signals received by the interface circuit 1120 , and can send the processing completion information through the interface circuit 1120 .
- the chip further includes a memory, which may include a read-only memory and a random access memory, and provides operation instructions and data to the processor.
- a portion of the memory may also include non-volatile random access memory (NVRAM).
- NVRAM non-volatile random access memory
- the memory stores executable software modules or data structures
- the processor may execute corresponding operations by calling operation instructions stored in the memory (the operation instructions may be stored in the operating system).
- the chip may be used in the active noise reduction system involved in the embodiments of the present application.
- the interface circuit 1120 may be used to output the execution result of the processor 1110 .
- processor 1110 and the interface circuit 1120 can be implemented by hardware design, software design, or a combination of software and hardware, which is not limited here.
- the active noise reduction device, computer storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved may refer to the above provided. The beneficial effects in the corresponding method will not be repeated here.
- the size of the sequence numbers of the above-mentioned processes does not mean the sequence of execution, and the execution sequence of each process should be determined by its functions and internal logic, and should not be dealt with in the embodiments of the present application. implementation constitutes any limitation.
- the disclosed system, apparatus and method may be implemented in other manners.
- the apparatus embodiments described above are only illustrative.
- the division of the units is only a logical function division. In actual implementation, there may be other division methods.
- multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented.
- the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.
- the units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.
- each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.
- the functions, if implemented in the form of software functional units and sold or used as independent products, may be stored in a computer-readable storage medium.
- the technical solution of the present application can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution, and the computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application.
- the aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk and other media that can store program codes .
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Abstract
The present application provides an active noise control method and apparatus, and an audio playback device, capable of improving the noise control effect of high-frequency noise. Said method comprises: acquiring a first reference signal acquired by a reference sensor, the first reference signal being used to characterize ambient noise outside an audio playback device, and the reference sensor being provided outside the audio playback device; performing pre-emphasis processing on the first reference signal, to obtain a target reference signal; performing filtering processing on the target reference signal, to obtain a first output signal for noise control, the phase of the first output signal being opposite to that of the target reference signal; performing de-emphasis processing on the first output signal, to obtain a target output signal; and controlling a loudspeaker to play back the target output signal.
Description
本申请要求于2020年7月24日递交的申请号为202010725144.9、申请名称为“主动降噪方法和装置以及音频播放设备”的中国专利申请的优先权,其全部内容通过引用结合在本申请中。This application claims the priority of the Chinese patent application with the application number 202010725144.9 and the application name "active noise reduction method and device, and audio playback device" filed on July 24, 2020, the entire contents of which are incorporated into this application by reference .
本申请涉及主动降噪技术领域,尤其是用于耳机的主动降噪技术。并且更具体地,涉及主动降噪技术领域中的主动降噪方法和装置以及音频播放设备。The present application relates to the field of active noise reduction technology, in particular to the active noise reduction technology for earphones. And more particularly, it relates to an active noise reduction method and device and an audio playback device in the field of active noise reduction technology.
主动降噪(active noise control,ANC)是一种降噪技术,是应用在耳机降噪的方法之一。主动降噪功能就指通过降噪系统产生与外界噪音相等的反向声波,将噪音中和,从而实现降噪的效果。Active noise control (ANC) is a noise reduction technology and one of the methods used in earphone noise reduction. The active noise reduction function refers to the generation of reverse sound waves equal to the external noise through the noise reduction system to neutralize the noise, thereby achieving the effect of noise reduction.
主动降噪的基本原理是基于设置在耳机外部的参考麦克风采集得到的参考信号和/或设置在耳机内部的误差麦克风采集得到的误差信号,以最快的速度计算出该参考信号的反相声波,然后控制扬声器播放该反向声波,以达到主动降噪效果。因此,计算出反相声波的时延越低,主动降噪的效果越好,否则容易起反作用。The basic principle of active noise reduction is to calculate the reverse phase sound wave of the reference signal at the fastest speed based on the reference signal collected by the reference microphone set outside the headset and/or the error signal collected by the error microphone set inside the headset. , and then control the speaker to play the reverse sound wave to achieve the effect of active noise reduction. Therefore, it is calculated that the lower the time delay of the anti-phase sound wave is, the better the effect of active noise reduction is, otherwise it is easy to have an adverse effect.
然而,由于不同的音频频率对应的波长不同,所需要计算反相声波的时间也不同。其中,音频频率越高,其所需要的计算反向声波的时间越短,甚至为亚毫秒级别。因此,现有的主动降噪系统对高频噪声的降噪效果较差。However, due to the different wavelengths corresponding to different audio frequencies, the time required to calculate the inverse sound waves is also different. Among them, the higher the audio frequency, the shorter the time required to calculate the reverse sound wave, even in the sub-millisecond level. Therefore, the existing active noise reduction system has poor noise reduction effect on high frequency noise.
发明内容SUMMARY OF THE INVENTION
本申请实施例提供的主动降噪方法和装置以及音频播放设备,能够提高对高频噪声的降噪效果。The active noise reduction method and device and the audio playback device provided by the embodiments of the present application can improve the noise reduction effect on high frequency noise.
第一方面,本申请实施例提供一种复合式主动降噪系统。该系统可以适用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。该系统可以包括参考传感器(如参考麦克风)、误差传感器(如误差麦克风)、扬声器和主动降噪装置,其中,该主动降噪装置包括第一预加重模块、第二预加重模块、控制模块和去加重模块。该参考传感器通过该第一预加重模块与该控制模块的第一输入端连接,该误差传感器通过该第二预加重模块与该控制模块的第二输入端连接,该扬声器通过该去加重模块与该控制模块的输出端连接。In a first aspect, embodiments of the present application provide a composite active noise reduction system. The system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. The system may include a reference sensor (eg, a reference microphone), an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first pre-emphasis module, a second pre-emphasis module, a control module, and De-emphasis module. The reference sensor is connected to the first input terminal of the control module through the first pre-emphasis module, the error sensor is connected to the second input terminal of the control module through the second pre-emphasis module, and the speaker is connected to the control module through the de-emphasis module. The output of the control module is connected.
该参考传感器用于采集该耳机外部的环境噪声,得到第一参考信号x(n);向该第一预加重模块发送该第一参考信号x(n)。The reference sensor is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first pre-emphasis module.
该第一预加重模块用于接收来自该参考传感器的第一参考信号x(n);对该第一参考信号x(n)进行预加重处理,得到目标参考信号x
1(n);向该控制模块的第一输入端发送该目标 参考信号x
1(n)。
The first pre-emphasis module is configured to receive the first reference signal x(n) from the reference sensor; perform pre-emphasis processing on the first reference signal x(n) to obtain the target reference signal x 1 (n); The first input terminal of the control module sends the target reference signal x 1 (n).
需要说明的是,经过预加重处理后的信号的高频部分的频点能量高于原始信号的高频部分的频点能量,也就是说,经过预加重处理后的信号的高频部分的分辨率高于原始信号的高频部分的分辨率。因此,能够提高控制模块处理的信号的高频分辨率,从而提高高频噪声的降噪效果。It should be noted that the frequency energy of the high frequency part of the pre-emphasized signal is higher than the frequency energy of the high frequency part of the original signal, that is to say, the resolution of the high frequency part of the pre-emphasized signal higher than the resolution of the high frequency portion of the original signal. Therefore, the high-frequency resolution of the signal processed by the control module can be improved, thereby improving the noise reduction effect of high-frequency noise.
需要说明的是,本申请实施例中该的高频部分可以理解为起始频率大于或等于预设的频率阈值的第一频段,相应地,低频部分可以理解为截止频率小于该频率阈值的第二频段。It should be noted that, in the embodiment of the present application, the high frequency part can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the first frequency band whose cutoff frequency is less than the frequency threshold. two frequency bands.
例如:该第一频率阈值可以为4000赫兹,信号中频率大于或等于4000赫兹的部分称为高频部分,频率小于4000赫兹的部分称为低频部分。For example, the first frequency threshold may be 4000 Hz, the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part, and the part whose frequency is less than 4000 Hz is called the low frequency part.
可选地,该第一预加重模块所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the first pre-emphasis module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第一预加重模块可以包括第一预加重电路,该第一预加重电路用于实现该第一预加重模块的功能。In a possible implementation manner, the first pre-emphasis module may include a first pre-emphasis circuit, and the first pre-emphasis circuit is configured to implement the function of the first pre-emphasis module.
该误差传感器用于采集该耳机内部的残留噪声,得到第一误差信号e(n);向该第二预加重模块发送该第一误差信号e(n)。The error sensor is used to collect residual noise inside the earphone to obtain a first error signal e(n); and send the first error signal e(n) to the second pre-emphasis module.
该第二预加重模块用于接收来自该误差传感器的第一误差信号e(n);对该第一误差信号e(n)进行预加重处理,得到目标误差信号e
1(n);向该控制模块的第二输入端发送该目标误差信号e
1(n)。
The second pre-emphasis module is configured to receive the first error signal e(n) from the error sensor; perform pre-emphasis processing on the first error signal e(n) to obtain the target error signal e 1 (n); A second input of the control module sends the target error signal e 1 (n).
需要说明的是,该第二预加重模块的处理过程可以参考上述第一预加重模块的处理过程,为避免重复,此处不再赘述。It should be noted that, for the processing procedure of the second pre-emphasis module, reference may be made to the above-mentioned processing procedure of the first pre-emphasis module, and to avoid repetition, details are not repeated here.
该控制模块用于接收来自该第一预加重模块的该目标参考信号x
1(n)和来自该第二预加重模块的该目标误差信号e
1(n);根据该目标误差信号e
1(n),对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该去加重模块发送该第一输出信号y(n)。
The control module is configured to receive the target reference signal x 1 (n) from the first pre-emphasis module and the target error signal e 1 (n) from the second pre-emphasis module; according to the target error signal e 1 ( n), perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); send the first output signal y(n) to the de-emphasis module.
可选地,该控制模块可以包括自适应滤波器。Optionally, the control module may include an adaptive filter.
需要说明的是,自适应滤波器是指根据环境的改变,使用自适应
算法来改变滤波器的参数和结构的滤波器。一般情况下,不改变自适应滤波器的结构。而自适应滤波器的系数是由自适应
算法更新的时变系数。即其系数自动连续地适应于给定信号,以获得期望响应。自适应滤波器的最重要的特征就在于它能够在未知环境中有效工作,并能够跟踪输入信号的时变特征。
Incidentally, the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter. In general, the structure of the adaptive filter is not changed. The coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response. The most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
可选地,该控制模块所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the control module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该控制模块可以包括控制电路,该控制电路用于实现该控制模块的功能。In a possible implementation manner, the control module may include a control circuit, and the control circuit is used to implement the function of the control module.
可选地,该控制模块为自适应滤波器时,该自适应滤波器可以采用多种自适应滤波算法,本申请实施例对此不作限定。Optionally, when the control module is an adaptive filter, the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该自适应滤波器可以采用最小均方差算法。In a possible implementation manner, the adaptive filter may use a minimum mean square error algorithm.
该去加重模块用于接收来自该控制模块的该第一输出信号y(n);对该第一输出信号y(n)进行去加重处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The de-emphasis module is used to receive the first output signal y(n) from the control module; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); send it to the speaker The target output signal y 1 (n).
可选地,该去加重模块所实现的功能可以通过硬件或软件实现,本申请实施例对此不 作限定。Optionally, the function implemented by the de-emphasis module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该去加重模块可以包括去加重电路,该去加重电路用于实现该去加重模块的功能。In a possible implementation manner, the de-emphasis module may include a de-emphasis circuit, and the de-emphasis circuit is used to implement the function of the de-emphasis module.
该扬声器用于接收来自该去加重模块的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker is used for receiving the target output signal y 1 (n) from the de-emphasis module; playing the target output signal y 1 (n).
本申请实施例提供的主动降噪系统,通过预加重模块提高第一参考信号和第一误差信号的高频部分的分辨率,然后输入控制模块进行自适应滤波,并通过去加重模块恢复控制模块输出的第一输出信号的高频部分的分辨率,并控制扬声器进行播放。也就是说,本申请实施例提供的主动降噪系统,通过预加重模块和去加重模块提高控制模块处理的信号的高频分辨率,从而能够提高对高频噪声的降噪效果。In the active noise reduction system provided by the embodiment of the present application, the resolution of the first reference signal and the high frequency part of the first error signal is improved by the pre-emphasis module, and then input to the control module for adaptive filtering, and the control module is restored by the de-emphasis module Output the resolution of the high frequency part of the first output signal, and control the speaker to play. That is to say, in the active noise reduction system provided by the embodiments of the present application, the pre-emphasis module and the de-emphasis module improve the high-frequency resolution of the signal processed by the control module, thereby improving the noise reduction effect on high-frequency noise.
第二方面,本申请实施例还提供一种前馈式主动降噪系统。该系统可以适用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。该系统可以包括参考传感器(如参考麦克风)、扬声器和主动降噪装置,其中,该主动降噪装置包括第一预加重模块控制模块和去加重模块。该参考传感器通过该第一预加重模块与该控制模块的第一输入端连接,该扬声器通过该去加重模块与该控制模块的输出端连接。In a second aspect, the embodiments of the present application further provide a feedforward active noise reduction system. The system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. The system may include a reference sensor (eg, a reference microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first pre-emphasis module control module and a de-emphasis module. The reference sensor is connected to the first input end of the control module through the first pre-emphasis module, and the speaker is connected to the output end of the control module through the de-emphasis module.
该参考传感器用于采集该耳机外部的环境噪声,得到第一参考信号x(n);向该第一预加重模块发送该第一参考信号x(n)。The reference sensor is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first pre-emphasis module.
该第一预加重模块用于接收来自该参考传感器的第一参考信号x(n);对该第一参考信号x(n)进行预加重处理,得到目标参考信号x
1(n);向该控制模块的第一输入端发送该目标参考信号x
1(n)。
The first pre-emphasis module is configured to receive the first reference signal x(n) from the reference sensor; perform pre-emphasis processing on the first reference signal x(n) to obtain the target reference signal x 1 (n); The first input terminal of the control module sends the target reference signal x 1 (n).
该控制模块用于接收来自该第一预加重模块的该目标参考信号x
1(n);对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该去加重模块发送该第一输出信号y(n)。
The control module is configured to receive the target reference signal x 1 (n) from the first pre-emphasis module; perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); The first output signal y(n) is sent to the de-emphasis module.
该去加重模块用于接收来自该控制模块的该第一输出信号y(n);对该第一输出信号y(n)进行去加重处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The de-emphasis module is used to receive the first output signal y(n) from the control module; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); send it to the speaker The target output signal y 1 (n).
该扬声器用于接收来自该去加重模块的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker is used for receiving the target output signal y 1 (n) from the de-emphasis module; playing the target output signal y 1 (n).
第三方面,本申请实施例还提供一种反馈式主动降噪系统。该系统可以适用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。该系统可以包括误差传感器(如误差麦克风)、扬声器和主动降噪装置,其中,该主动降噪装置包括第二预加重模块、控制模块和去加重模块。该误差传感器通过该第二预加重模块与该控制模块的第二输入端连接,该扬声器通过该去加重模块与该控制模块的输出端连接。In a third aspect, the embodiments of the present application further provide a feedback active noise reduction system. The system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. The system may include an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a second pre-emphasis module, a control module, and a de-emphasis module. The error sensor is connected to the second input end of the control module through the second pre-emphasis module, and the speaker is connected to the output end of the control module through the de-emphasis module.
该误差传感器用于采集该耳机内部的残留噪声,得到第一误差信号e(n);向该第二预加重模块发送该第一误差信号e(n)。The error sensor is used to collect residual noise inside the earphone to obtain a first error signal e(n); and send the first error signal e(n) to the second pre-emphasis module.
该第二预加重模块用于接收来自该误差传感器的第一误差信号e(n);对该第一误差信号e(n)进行预加重处理,得到目标误差信号e
1(n);向该控制模块的第二输入端发送该目标误差信号e
1(n)。
The second pre-emphasis module is configured to receive the first error signal e(n) from the error sensor; perform pre-emphasis processing on the first error signal e(n) to obtain the target error signal e 1 (n); A second input of the control module sends the target error signal e 1 (n).
该控制模块用于接收来自该第二预加重模块的该目标误差信号e
1(n);根据该目标误差信号e
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该去加重模块发送该第一输出 信号y(n)。
The control module is configured to receive the target error signal e 1 (n) from the second pre-emphasis module; perform adaptive filtering processing according to the target error signal e 1 (n) to obtain a first output signal y(n); The first output signal y(n) is sent to the de-emphasis module.
该去加重模块用于接收来自该控制模块的该第一输出信号y(n);对该第一输出信号y(n)进行去加重处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The de-emphasis module is used to receive the first output signal y(n) from the control module; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); send it to the speaker The target output signal y 1 (n).
该扬声器用于接收来自该去加重模块的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker is used for receiving the target output signal y 1 (n) from the de-emphasis module; playing the target output signal y 1 (n).
第四方面,本申请实施例提供一种复合式主动降噪系统。该系统可以应用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。该系统可以包括参考传感器(如参考麦克风)、误差传感器(如误差麦克风)、扬声器和主动降噪装置,其中,该主动降噪装置包括第一低通滤波模块、第二低通滤波模块、控制模块和带宽扩展模块。该参考传感器通过该第一低通滤波模块与该控制模块的第一输入端连接,该误差传感器通过该第二低通滤波模块与该控制模块的第二输入端连接,该扬声器通过该与该控制模块的输出端连接。该参考传感器用于采集该耳机外部的环境噪声,得到第一参考信号x(n);向该第一低通滤波模块发送该第一参考信号x(n)。In a fourth aspect, embodiments of the present application provide a composite active noise reduction system. The system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. The system may include a reference sensor (eg, a reference microphone), an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first low-pass filtering module, a second low-pass filtering module, a control modules and bandwidth extension modules. The reference sensor is connected to the first input end of the control module through the first low-pass filter module, the error sensor is connected to the second input end of the control module through the second low-pass filter module, and the speaker is connected to the second input end of the control module through the second low-pass filter module. The output terminals of the control module are connected. The reference sensor is used for collecting ambient noise outside the earphone to obtain a first reference signal x(n); and sending the first reference signal x(n) to the first low-pass filtering module.
该第一低通滤波模块用于接收来自该参考传感器的第一参考信号x(n);对该第一参考信号x(n)进行低通滤波处理,得到目标参考信号x
1(n);向该控制模块的第一输入端发送该目标参考信号x
1(n)。
The first low-pass filtering module is configured to receive a first reference signal x(n) from the reference sensor; perform low-pass filtering processing on the first reference signal x(n) to obtain a target reference signal x 1 (n); The target reference signal x 1 (n) is sent to the first input of the control module.
需要说明的是,经过低通滤波处理后的信号滤除了原始信号中的高频部分,仅包含稳定性更高的低频部分。因此,能够提高控制模块处理的信号的高频稳定性和鲁棒性,从而提高高频噪声的降噪效果。It should be noted that the low-pass filtering signal has filtered out the high-frequency part in the original signal, and only contains the low-frequency part with higher stability. Therefore, the high-frequency stability and robustness of the signal processed by the control module can be improved, thereby improving the noise reduction effect of high-frequency noise.
需要说明的是,本申请实施例中该的高频部分可以理解为起始频率大于或等于预设的频率阈值的第一频段,相应地,低频部分可以理解为截止频率小于该频率阈值的第二频段。It should be noted that, in the embodiment of the present application, the high frequency part can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the first frequency band whose cutoff frequency is less than the frequency threshold. two frequency bands.
例如:该第一频率阈值可以为4000赫兹,信号中频率大于或等于4000赫兹的部分称为高频部分,频率小于4000赫兹的部分称为低频部分。For example, the first frequency threshold may be 4000 Hz, the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part, and the part whose frequency is less than 4000 Hz is called the low frequency part.
在一种可能的实现方式中,该第一低通滤波模块具体用于对该第一参考信号x(n)进行下采样,得到该目标参考信号x
1(n)。
In a possible implementation manner, the first low-pass filtering module is specifically configured to downsample the first reference signal x(n) to obtain the target reference signal x 1 (n).
例如:以该x(n)为4KHz的频率宽度,该第一低通滤波模块具体用于每四个音频采样点抽取一个音频采样点,得到下采样后的x
1(n),其频率宽度为1kHz频宽。
For example: taking this x(n) as the frequency width of 4KHz, the first low-pass filtering module is specifically used to extract an audio sampling point for every four audio sampling points to obtain the down-sampled x 1 (n), whose frequency width is is 1kHz bandwidth.
可选地,该第一低通滤波模块所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the first low-pass filtering module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第一低通滤波模块可以包括第一低通滤波电路,该第一低通滤波电路用于实现该第一低通滤波模块的功能。In a possible implementation manner, the first low-pass filtering module may include a first low-pass filtering circuit, and the first low-pass filtering circuit is configured to implement the function of the first low-pass filtering module.
该误差传感器用于采集该耳机内部的残留噪声,得到第一误差信号e(n);向该第二低通滤波模块发送该第一误差信号e(n)。The error sensor is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second low-pass filtering module.
该第二低通滤波模块用于接收来自该误差传感器的第一误差信号e(n);对该第一误差信号e(n)进行低通滤波处理,得到目标误差信号e
1(n);向该控制模块的第二输入端发送该目标误差信号e
1(n)。
The second low-pass filtering module is configured to receive the first error signal e(n) from the error sensor; perform low-pass filtering processing on the first error signal e(n) to obtain the target error signal e 1 (n); The target error signal e 1 (n) is sent to a second input of the control module.
需要说明的是,该第二低通滤波模块的处理过程可以参考上述第一低通滤波模块的处理过程,为避免重复,此处不再赘述。It should be noted that, for the processing procedure of the second low-pass filtering module, reference may be made to the processing procedure of the above-mentioned first low-pass filtering module, which is not repeated here to avoid repetition.
可选地,该第二低通滤波模块所实现的功能可以通过硬件或软件实现,本申请实施例 对此不作限定。Optionally, the function implemented by the second low-pass filtering module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第二低通滤波模块可以包括第二低通滤波电路,该第二低通滤波电路用于实现该第二低通滤波模块的功能。In a possible implementation manner, the second low-pass filtering module may include a second low-pass filtering circuit, and the second low-pass filtering circuit is configured to implement the function of the second low-pass filtering module.
该控制模块用于接收来自该第一低通滤波模块的该目标参考信号x
1(n)和来自该第二低通滤波模块的该目标误差信号e
1(n);根据该目标误差信号e
1(n),对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该发送该第一输出信号y(n)。
The control module is configured to receive the target reference signal x 1 (n) from the first low-pass filtering module and the target error signal e 1 (n) from the second low-pass filtering module; according to the target error signal e 1 (n), perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); send the first output signal y(n) to the target reference signal y(n).
可选地,该控制模块可以包括自适应滤波器。Optionally, the control module may include an adaptive filter.
需要说明的是,自适应滤波器是指根据环境的改变,使用自适应
算法来改变滤波器的参数和结构的滤波器。一般情况下,不改变自适应滤波器的结构。而自适应滤波器的系数是由自适应
算法更新的时变系数。即其系数自动连续地适应于给定信号,以获得期望响应。自适应滤波器的最重要的特征就在于它能够在未知环境中有效工作,并能够跟踪输入信号的时变特征。
Incidentally, the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter. In general, the structure of the adaptive filter is not changed. The coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response. The most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
可选地,该控制模块所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the control module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该控制模块可以包括控制电路,该控制电路用于实现该控制模块的功能。In a possible implementation manner, the control module may include a control circuit, and the control circuit is used to implement the function of the control module.
可选地,该控制模块为自适应滤波器时,该自适应滤波器可以采用多种自适应滤波算法,本申请实施例对此不作限定。Optionally, when the control module is an adaptive filter, the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该自适应滤波器可以采用最小均方差算法。In a possible implementation manner, the adaptive filter may use a minimum mean square error algorithm.
该带宽扩展模块用于接收来自该控制模块的该第一输出信号y(n);对该第一输出信号y(n)进行带宽扩展处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The bandwidth expansion module is used for receiving the first output signal y(n) from the control module; performing bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); sending it to the speaker The target output signal y 1 (n).
可选地,该带宽扩展模块可以通过多种方式,对该第一输出信号进行带宽扩展处理,得到目标输出信号,本申请实施例对此不作限定。Optionally, the bandwidth expansion module may perform bandwidth expansion processing on the first output signal in various manners to obtain the target output signal, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该带宽扩展模块可以通过盲目式高频重建法,对该第一输出信号进行带宽扩展处理,得到目标输出信号。In a possible implementation manner, the bandwidth expansion module may perform bandwidth expansion processing on the first output signal through a blind high-frequency reconstruction method to obtain the target output signal.
可选地,盲目式高频重建法可以包括:线性外推(linear extrapolation,LE)、有效高频带宽扩展(efficient high-frequency bandwidth extension,EHBE)、混合信号外推(hybrid signal extrapolation,HSE)和非线性预测等。Optionally, the blind high-frequency reconstruction method may include: linear extrapolation (LE), efficient high-frequency bandwidth extension (EHBE), hybrid signal extrapolation (HSE) and nonlinear prediction.
需要说明的是,线性外推法是指音频信号的对数幅度谱包络呈近似线性递减关系来进行高频重建,其中,高频重建包括高频部分频域包络和高频部分频谱细节两部分。其中,高频谱包络可以借助幅度谱的线性关系获得,高频谱细节可以通过复制低频带的谐波结构获得。It should be noted that the linear extrapolation method means that the logarithmic amplitude spectral envelope of the audio signal is in an approximately linearly decreasing relationship to perform high-frequency reconstruction, wherein the high-frequency reconstruction includes the frequency domain envelope of the high-frequency part and the spectral details of the high-frequency part. two parts. Among them, the high spectral envelope can be obtained by the linear relationship of the amplitude spectrum, and the high spectral details can be obtained by replicating the harmonic structure of the low frequency band.
在一种可能的实现方式中,该带宽扩展模块具体用于对低频信号y(n)进行时频变换得到其谱包络;采用线性最小二乘法将该包络在对数域拟合成一条直线,得到该直线的最佳斜率和截距;将低频部分的频谱信息进行复制得到高频部分的频谱细节;利用拟合直线的斜率对高频谱细节进行包络衰减,完成高频部分的重建,从而得到完整的、包括高频部分和低频部分的信号y
1(n)。
In a possible implementation manner, the bandwidth expansion module is specifically used to perform time-frequency transformation on the low-frequency signal y(n) to obtain its spectral envelope; use the linear least squares method to fit the envelope into a logarithmic domain straight line to obtain the best slope and intercept of the straight line; copy the spectral information of the low-frequency part to obtain the spectral details of the high-frequency part; use the slope of the fitted straight line to perform envelope attenuation on the high-frequency spectral details to complete the reconstruction of the high-frequency part , so as to obtain a complete signal y 1 (n) including high frequency part and low frequency part.
可选地,该带宽扩展模块所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the bandwidth expansion module may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该带宽扩展模块可以包括带宽扩展电路,该带宽扩展电路用于实现该带宽扩展模块的功能。In a possible implementation manner, the bandwidth extension module may include a bandwidth extension circuit, and the bandwidth extension circuit is configured to implement the function of the bandwidth extension module.
该扬声器用于接收来自该带宽扩展模块的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker is used for receiving the target output signal y 1 (n) from the bandwidth expansion module; playing the target output signal y 1 (n).
本申请实施例提供的主动降噪系统,通过第一低通滤波模块滤除第一参考信号中稳定性较差的高频部分和/或通过第二低通滤波模块滤除第一误差信号中稳定性较差的高频部分,只留下第一参考信号和第一误差信号中稳定性较强的低频部分然后输入控制模块进行自适应滤波,并通过带宽扩展模块重建出控制模块输出的第一输出信号的高频部分,得到完整带宽(既包含高频部分也包含低频部分)的目标输出信号,并控制扬声器进行播放。也就是说,通过低通滤波模块和带宽扩展模块提高控制模块处理的信号的高频部分的稳定性和鲁棒性,从而提高高频噪声的降噪效果。In the active noise reduction system provided by the embodiment of the present application, the first low-pass filtering module filters out the high-frequency part with poor stability in the first reference signal and/or the second low-pass filtering module filters out the first error signal. For the high-frequency part with poor stability, only the low-frequency part with strong stability in the first reference signal and the first error signal is left, and then it is input to the control module for adaptive filtering, and the first reference signal output by the control module is reconstructed through the bandwidth expansion module. A high-frequency part of an output signal, obtain a target output signal with a complete bandwidth (including both high-frequency part and low-frequency part), and control the speaker to play. That is, the stability and robustness of the high-frequency part of the signal processed by the control module are improved through the low-pass filtering module and the bandwidth expansion module, thereby improving the noise reduction effect of high-frequency noise.
第五方面,本申请实施例还提供一种前馈式主动降噪系统。该系统可以应用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。该系统可以包括参考传感器(如参考麦克风)、扬声器和主动降噪装置,其中,该主动降噪装置包括第一低通滤波模块、控制模块和带宽扩展模块。该参考传感器通过该第一低通滤波模块与该控制模块的第一输入端连接,该扬声器通过该与该控制模块的输出端连接。In a fifth aspect, the embodiments of the present application further provide a feedforward active noise reduction system. The system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. The system may include a reference sensor (eg, a reference microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a first low-pass filtering module, a control module, and a bandwidth expansion module. The reference sensor is connected to the first input end of the control module through the first low-pass filter module, and the speaker is connected to the output end of the control module through this.
该参考传感器用于采集该耳机外部的环境噪声,得到第一参考信号x(n);向该第一低通滤波模块发送该第一参考信号x(n)。The reference sensor is used for collecting ambient noise outside the earphone to obtain a first reference signal x(n); and sending the first reference signal x(n) to the first low-pass filtering module.
该第一低通滤波模块用于接收来自该参考传感器的第一参考信号x(n);对该第一参考信号x(n)进行低通滤波处理,得到目标参考信号x
1(n);向该控制模块的第一输入端发送该目标参考信号x
1(n)。
The first low-pass filtering module is configured to receive a first reference signal x(n) from the reference sensor; perform low-pass filtering processing on the first reference signal x(n) to obtain a target reference signal x 1 (n); The target reference signal x 1 (n) is sent to the first input of the control module.
该控制模块用于接收来自该第一低通滤波模块的该目标参考信号x
1(n);对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该发送该第一输出信号y(n)。
The control module is configured to receive the target reference signal x 1 (n) from the first low-pass filtering module; perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n) ; send the first output signal y(n) to this.
该带宽扩展模块用于接收来自该控制模块的该第一输出信号y(n);对该第一输出信号y(n)进行带宽扩展处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The bandwidth expansion module is used for receiving the first output signal y(n) from the control module; performing bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); sending it to the speaker The target output signal y 1 (n).
该扬声器用于接收来自该带宽扩展模块的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker is used for receiving the target output signal y 1 (n) from the bandwidth expansion module; playing the target output signal y 1 (n).
第六方面,本申请实施例提供一种反馈式主动降噪系统。该系统可以应用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。该系统可以包括误差传感器(如误差麦克风)、扬声器和主动降噪装置,其中,该主动降噪装置包括第二低通滤波模块、控制模块和带宽扩展模块。该误差传感器通过该第二低通滤波模块与该控制模块的第二输入端连接,该扬声器通过该与该控制模块的输出端连接。In a sixth aspect, an embodiment of the present application provides a feedback active noise reduction system. The system can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. The system may include an error sensor (eg, an error microphone), a speaker, and an active noise reduction device, wherein the active noise reduction device includes a second low-pass filter module, a control module, and a bandwidth expansion module. The error sensor is connected to the second input end of the control module through the second low-pass filter module, and the speaker is connected to the output end of the control module through the second low-pass filter module.
该误差传感器用于采集该耳机内部的残留噪声,得到第一误差信号e(n);向该第二低通滤波模块发送该第一误差信号e(n)。The error sensor is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second low-pass filtering module.
该第二低通滤波模块用于接收来自该误差传感器的第一误差信号e(n);对该第一误差信号e(n)进行低通滤波处理,得到目标误差信号e
1(n);向该控制模块的第二输入端发送该目标误差信号e
1(n)。
The second low-pass filtering module is configured to receive the first error signal e(n) from the error sensor; perform low-pass filtering processing on the first error signal e(n) to obtain the target error signal e 1 (n); The target error signal e 1 (n) is sent to a second input of the control module.
该控制模块用于接收来自该第二低通滤波模块的该目标误差信号e
1(n);根据该目标误差信号e
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该发送该第一输出信号y(n)。
The control module is configured to receive the target error signal e 1 (n) from the second low-pass filtering module; perform adaptive filtering processing according to the target error signal e 1 (n) to obtain a first output signal y(n) ; send the first output signal y(n) to this.
该带宽扩展模块用于接收来自该控制模块的该第一输出信号y(n);对该第一输出信号y(n)进行带宽扩展处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The bandwidth expansion module is used for receiving the first output signal y(n) from the control module; performing bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); sending it to the speaker The target output signal y 1 (n).
该扬声器用于接收来自该带宽扩展模块的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker is used for receiving the target output signal y 1 (n) from the bandwidth expansion module; playing the target output signal y 1 (n).
第七方面,本申请实施例还提供一种主动降噪方法,该方法可以包括上述各方面或其各种可能的实现方式中由主动降噪装置执行的方法。In a seventh aspect, the embodiments of the present application further provide an active noise reduction method, and the method may include the methods performed by the active noise reduction apparatus in the above aspects or various possible implementation manners thereof.
第八方面,本申请实施例还提供一种主动降噪装置,该装置包括:存储器、至少一个处理器、收发器及存储在该存储器上并可在该处理器上运行的指令。进一步,该存储器、该处理器以及该通信接口之间通过内部连接通路互相通信。所述至少一个处理器执行该指令使得该装置实现上述各方面或其任意可能的实现方式中由主动降噪装置执行的方法。In an eighth aspect, an embodiment of the present application further provides an active noise reduction device, the device includes: a memory, at least one processor, a transceiver, and instructions stored on the memory and executable on the processor. Further, the memory, the processor and the communication interface communicate with each other through an internal connection path. Execution of the instructions by the at least one processor causes the apparatus to implement the method performed by the active noise reduction apparatus in the aspects or any possible implementations thereof.
第九方面,本申请还提供一种计算机可读存储介质,用于存储计算机程序,该计算机程序包括用于实现上述第一方面或其任意可能的实现方式中由主动降噪装置执行的方法。In a ninth aspect, the present application further provides a computer-readable storage medium for storing a computer program, the computer program including a method for implementing the above-mentioned first aspect or any possible implementation manners thereof and executed by an active noise reduction apparatus.
第十方面,本申请还提供一种包含指令的计算机程序产品,当其在计算机上运行时,使得计算机实现上述各个方面或其任意可能的实现方式中由主动降噪装置执行的方法。In a tenth aspect, the present application also provides a computer program product comprising instructions, which, when run on a computer, enable the computer to implement the method performed by the active noise reduction device in each of the above aspects or any possible implementations thereof.
第十一方面,本申请还提供一种芯片装置,包括:输入接口、输出接口、至少一个处理器。可选的,所述芯片装置还包括存储器。该至少一个处理器用于执行该存储器中的代码,当该至少一个处理器执行该代码时,该芯片装置实现上述各个方面或其任意可能的实现方式中由主动降噪装置执行的方法。In an eleventh aspect, the present application further provides a chip device, including: an input interface, an output interface, and at least one processor. Optionally, the chip device further includes a memory. The at least one processor is configured to execute the code in the memory, and when the at least one processor executes the code, the chip device implements the method performed by the active noise reduction apparatus in the above-mentioned various aspects or any possible implementation manners thereof.
图1是本申请实施例提供的主动降噪原理示意图;1 is a schematic diagram of an active noise reduction principle provided by an embodiment of the present application;
图2是本申请实施例提供的前馈式主动降噪系统的场景示意图;2 is a schematic diagram of a scene of a feedforward active noise reduction system provided by an embodiment of the present application;
图3是本申请实施例提供的前馈式主动降噪系统的原理示意图;3 is a schematic diagram of the principle of a feedforward active noise reduction system provided by an embodiment of the present application;
图4是本申请实施例提供的反馈式主动降噪系统的场景示意图;4 is a schematic diagram of a scene of a feedback active noise reduction system provided by an embodiment of the present application;
图5是本申请实施例提供的反馈式主动降噪系统的原理示意图;5 is a schematic diagram of the principle of a feedback active noise reduction system provided by an embodiment of the present application;
图6是本申请实施例提供的复合式主动降噪系统的场景示意图;6 is a schematic diagram of a scene of a composite active noise reduction system provided by an embodiment of the present application;
图7是本申请实施例提供的复合式主动降噪系统的原理示意图;7 is a schematic diagram of the principle of a composite active noise reduction system provided by an embodiment of the present application;
图8是本申请实施例提供的一种应用场景示意图;FIG. 8 is a schematic diagram of an application scenario provided by an embodiment of the present application;
图9是本申请实施例提供的另一种应用场景示意图;FIG. 9 is a schematic diagram of another application scenario provided by an embodiment of the present application;
图10是本申请实施例提供的又一种应用场景示意图;FIG. 10 is a schematic diagram of another application scenario provided by an embodiment of the present application;
图11是本申请实施例提供的又一种应用场景示意图;FIG. 11 is a schematic diagram of another application scenario provided by an embodiment of the present application;
图12是本申请实施例提供的又一种应用场景示意图;FIG. 12 is a schematic diagram of another application scenario provided by an embodiment of the present application;
图13是本申请实施例提供的又一种应用场景示意图;FIG. 13 is a schematic diagram of another application scenario provided by an embodiment of the present application;
图14是本申请实施例提供的主动降噪系统500的示意性框图;FIG. 14 is a schematic block diagram of an active noise reduction system 500 provided by an embodiment of the present application;
图15是本申请实施例提供的预加重处理的频谱示意图;15 is a schematic diagram of a spectrum of pre-emphasis processing provided by an embodiment of the present application;
图16是本申请实施例提供的另一主动降噪系统500的示意性框图;FIG. 16 is a schematic block diagram of another active noise reduction system 500 provided by an embodiment of the present application;
图17是本申请实施例提供的又一主动降噪系统500的示意性框图;FIG. 17 is a schematic block diagram of another active noise reduction system 500 provided by an embodiment of the present application;
图18是本申请实施例提供的主动降噪系统600的示意性框图;FIG. 18 is a schematic block diagram of an active noise reduction system 600 provided by an embodiment of the present application;
图19是本申请实施例提供的低通滤波处理的频谱示意图;19 is a schematic diagram of a spectrum of low-pass filtering processing provided by an embodiment of the present application;
图20是本申请实施例提供的另一主动降噪系统600的示意性框图;FIG. 20 is a schematic block diagram of another active noise reduction system 600 provided by an embodiment of the present application;
图21是本申请实施例提供的又一主动降噪系统600的示意性框图;FIG. 21 is a schematic block diagram of another active noise reduction system 600 provided by an embodiment of the present application;
图22是本申请实施例提供的主动降噪方法700的示意性流程图;FIG. 22 is a schematic flowchart of an active noise reduction method 700 provided by an embodiment of the present application;
图23是本申请实施例提供的另一主动降噪方法800的示意性流程图;FIG. 23 is a schematic flowchart of another active noise reduction method 800 provided by an embodiment of the present application;
图24是本申请实施例提供的主动降噪装置900的示意性框图;FIG. 24 is a schematic block diagram of an active noise reduction apparatus 900 provided by an embodiment of the present application;
图25是本申请实施例提供的主动降噪装置1000的示意性框图;FIG. 25 is a schematic block diagram of an active noise reduction apparatus 1000 provided by an embodiment of the present application;
图26是本申请实施例提供的芯片1100的示意性框图。FIG. 26 is a schematic block diagram of a chip 1100 provided by an embodiment of the present application.
下面将结合附图,对本申请中的技术方案进行描述。The technical solutions in the present application will be described below with reference to the accompanying drawings.
首先对本申请涉及的专业术语进行介绍。First, the technical terms involved in this application are introduced.
1、主动降噪的原理1. The principle of active noise reduction
主动降噪是一种通过引用来自次级声源的与初级声源的声波幅值相等、相位相反的声波来削弱初始噪声的噪声控制技术,次级声源的输出被用于干涉初级声源(噪声源),如图1所示。Active noise reduction is a noise control technique that attenuates initial noise by referencing sound waves from a secondary sound source that have the same amplitude and opposite phase as the primary sound source, and the output of the secondary sound source is used to interfere with the primary sound source. (noise source), as shown in Figure 1.
2、主动降噪的分类2. Classification of active noise reduction
按照控制电路分类可以包括:模拟式和数字式。According to the control circuit classification, it can include: analog and digital.
按照控制结构分类可以包括:前馈式(feed forward)、反馈(feed back)式和复合式。According to the control structure classification, it can include: feed forward, feedback and compound.
3、前馈式主动降噪系统3. Feedforward active noise reduction system
如图2所示,以用于入耳式耳机的主动降噪系统为例,前馈式主动降噪系统可以包括部署在耳机外部的参考传感器(如参考麦克风)、部署在耳机内部的控制器和扬声器。该控制器、该参考传感器和该扬声器之间的连接关系如图3所示。该参考传感器用于采集耳机外部的环境噪声(如图1中的初级噪声或噪声源),得到参考信号x(n),将该x(n)输入该控制器,该控制器用于对该x(n)做反相,得到输出信号y(n)(如图1中的次级噪声),该输出信号y(n)与噪声源的相位相反,该扬声器用于播放该输出信号y(n),从而实现对噪声源的降噪。As shown in Figure 2, taking the active noise reduction system for in-ear headphones as an example, the feedforward active noise cancellation system may include a reference sensor (such as a reference microphone) deployed outside the earphone, a controller deployed inside the earphone, and speaker. The connection relationship among the controller, the reference sensor and the speaker is shown in FIG. 3 . The reference sensor is used to collect ambient noise outside the earphone (such as the primary noise or noise source in Figure 1), to obtain a reference signal x(n), and input the x(n) to the controller, and the controller is used for the x(n) (n) Invert the phase to obtain the output signal y(n) (the secondary noise in Figure 1), the output signal y(n) is opposite to the phase of the noise source, and the speaker is used to play the output signal y(n) ) to achieve noise reduction of the noise source.
需要说明的是,本申请实施例中所述的耳机外部可以理解为耳机上远离人耳的一侧,耳机内部可以理解为耳机上靠近人耳的一侧。It should be noted that the outside of the earphone described in the embodiments of the present application can be understood as the side of the earphone that is far away from the human ear, and the inside of the earphone can be understood as the side of the earphone that is close to the human ear.
4、反馈式主动降噪系统4. Feedback active noise reduction system
如图4所示,以用于头戴式耳机的主动降噪系统为例,反馈式主动降噪系统可以包括部署在耳机内部的误差传感器(如误差麦克风)、控制器和扬声器。该控制器、该误差传感器和该扬声器之间的连接关系如图5所示。该误差传感器用于采集耳机内部的残留噪声(如图1中的残留噪声),得到误差信号e(n),将该e(n)输入该控制器,该控制器用于根据该e(n)进行自适应滤波,得到输出信号y(n)(如图1中的次级噪声),该输出信号y(n)与噪声源的相位相反,该扬声器用于播放该输出信号y(n),使得y(n)与噪声源叠加后得到的e(n)最小,这是一个闭环的过程。As shown in FIG. 4 , taking an active noise cancellation system for a headset as an example, the feedback active noise cancellation system may include an error sensor (eg, an error microphone), a controller, and a speaker deployed inside the headset. The connection relationship among the controller, the error sensor and the speaker is shown in FIG. 5 . The error sensor is used to collect the residual noise inside the earphone (such as the residual noise in Figure 1) to obtain the error signal e(n), and the e(n) is input to the controller, and the controller is used for according to the e(n) Perform adaptive filtering to obtain an output signal y(n) (secondary noise in Figure 1), the output signal y(n) is opposite to the phase of the noise source, and the speaker is used to play the output signal y(n), It is a closed-loop process to minimize e(n) obtained after y(n) is superimposed with the noise source.
5、复合式主动降噪系统5. Composite active noise reduction system
如图6所示,以用于头戴式耳机的主动降噪系统为例,反馈式主动降噪系统可以包括部署在耳机外部的参考传感器(如参考麦克风)、部署在耳机内部的误差传感器(如误差 麦克风)、控制器和扬声器。该控制器、该参考传感器、该误差传感器和该扬声器之间的连接关系如图7所示。该参考传感器用于采集耳机外部的环境噪声(如图1中的初级噪声或噪声源),得到的参考信号x(n),将该x(n)输入该控制器,该误差麦克风采集耳机内部的残留噪声(如图1中的残留噪声),得到误差信号e(n),将该e(n)输入该控制器,该控制器根据该e(n),对该x(n)进行自适应滤波,得到输出信号y(n)(如图1中次级噪声),该输出信号y(n)与噪声源的相位相反,通过该扬声器播放该输出信号y(n),使得y(n)与噪声源叠加后得到的e(n)最小。As shown in Figure 6, taking the active noise reduction system for headphones as an example, the feedback active noise reduction system may include a reference sensor (such as a reference microphone) deployed outside the earphone, an error sensor (such as a reference microphone) deployed inside the earphone such as error microphones), controllers and speakers. The connection relationship among the controller, the reference sensor, the error sensor and the speaker is shown in FIG. 7 . The reference sensor is used to collect the ambient noise outside the earphone (such as the primary noise or noise source in Figure 1), and the obtained reference signal x(n) is input to the controller, and the error microphone collects the inside of the earphone. The residual noise (residual noise in Figure 1) is obtained, the error signal e(n) is obtained, the e(n) is input to the controller, the controller according to the e(n), the x(n) is automatically Adaptive filtering to obtain an output signal y(n) (secondary noise in Figure 1), the output signal y(n) is opposite to the phase of the noise source, and the output signal y(n) is played through the speaker so that y(n ) and the noise source are superimposed to obtain the smallest e(n).
本申请实施例提供的主动降噪方法可以应用于音频播放设备。The active noise reduction method provided by the embodiment of the present application can be applied to an audio playback device.
可选地,本申请实施例中所述的音频播放设备是指用户佩戴在耳朵上或耳朵附近使用的音频播放设备,可以包括耳机、可穿戴智能设备等,本申请实施例对此不作限定。Optionally, the audio playback device described in this embodiment of the present application refers to an audio playback device worn on or near the ear by the user, which may include earphones, wearable smart devices, and the like, which are not limited in this embodiment of the present application.
可选地,当所述音频播放设备为耳机时,按照佩戴方式可以包括入耳式耳机、头戴式耳机等;按照连接方式可以包括:有线耳机、无线耳机,如蓝牙耳机等。Optionally, when the audio playback device is an earphone, it may include an in-ear earphone, a headphone, etc. according to the wearing method; and may include: wired earphones, wireless earphones, such as Bluetooth earphones, etc. according to the connection method.
可选地,当所述音频播放设备为可穿戴设备时,该可穿戴智能设备可以包括增强现实(augmented reality,AR)/虚拟现实(virtual reality,VR)设备,例如AR/VR头盔、AR/VR面罩、AR/VR眼镜等。Optionally, when the audio playback device is a wearable device, the wearable smart device may include augmented reality (AR)/virtual reality (VR) devices, such as AR/VR helmets, AR/VR VR masks, AR/VR glasses, etc.
需要说明的是,该音频播放设备可以不依赖智能终端(如智能手机)实现音频播放功能,或需要和智能终端(如智能手机)配合使用实现音频播放功能,本申请实施例对此不作限定。It should be noted that the audio playback device may implement the audio playback function without relying on an intelligent terminal (such as a smart phone), or may need to be used in conjunction with an intelligent terminal (such as a smart phone) to implement the audio playback function, which is not limited in this embodiment of the present application.
可选地,本申请实施例提供的主动降噪系统可适用于各种需要使用音频播放设备的降噪功能的场景,例如:接听电话、视频通话、播放音频或视频等的主动降噪场景,本申请实施例对此不作限定。Optionally, the active noise reduction system provided in the embodiment of the present application may be applicable to various scenarios that require the noise reduction function of an audio playback device, such as: an active noise reduction scenario of answering a phone call, video call, playing audio or video, etc., This embodiment of the present application does not limit this.
需要说明的是,下面将以该音频播放设备为耳机为例,介绍本申请实施例提供的主动降噪方法所适用的场景,但本申请实施例不限于此。当该音频播放设备为可穿戴设备时该主动降噪方法所适用的场景与耳机类似,为避免重复,此处不再赘述。It should be noted that the following will take the audio playback device as an earphone as an example to introduce the applicable scene of the active noise reduction method provided by the embodiment of the present application, but the embodiment of the present application is not limited thereto. When the audio playback device is a wearable device, the applicable scene of the active noise reduction method is similar to that of an earphone, and in order to avoid repetition, details are not repeated here.
可选地,耳机上可以设置有触发主动降噪指令的触发条件,当用户想要启用主动降噪功能时,可以对耳机进行操作,以触发耳机的主动降噪指令。Optionally, a trigger condition for triggering the active noise reduction instruction may be set on the earphone, and when the user wants to enable the active noise reduction function, the earphone can be operated to trigger the active noise reduction instruction of the earphone.
可选地,触发主动降噪指令的触发条件可以通过多种方式进行设置,本申请实施例对此不作限定。Optionally, the trigger condition for triggering the active noise reduction instruction may be set in various ways, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,耳机或耳机的线控上可以设置有触发主动降噪的实体按键等。当用户按压所述实体按键时,可以触发手势识别指令。In a possible implementation manner, a physical button or the like that triggers active noise reduction may be provided on the earphone or the wire control of the earphone. When the user presses the physical button, the gesture recognition instruction can be triggered.
例如:如图8中的所示,入耳式耳机100可以包括实体按键101,实体按键101为降噪键。用户在可以在需要使用耳机降噪功能时,用手指按压该实体按键101,触发主动降噪指令,启用主动降噪功能。For example, as shown in FIG. 8 , the in-ear headphone 100 may include a physical button 101 , and the physical button 101 is a noise reduction button. When the user needs to use the noise reduction function of the earphone, the user can press the physical button 101 with a finger to trigger an active noise reduction instruction and enable the active noise reduction function.
可选地,图8中所示的入耳式耳机100还可以为图9中所示的头戴式耳机100或图10中所示的蓝牙无线耳机100,本申请实施例对此不作限定。Optionally, the in-ear headphone 100 shown in FIG. 8 may also be the headphone 100 shown in FIG. 9 or the Bluetooth wireless headphone 100 shown in FIG. 10 , which is not limited in this embodiment of the present application.
又例如:如图11所示,入耳式线控耳机200可以包括耳机210和线控装置220,线控装置可以包括实体按键221和实体按键222,实体按键221为音量键,实体按键222为接听/挂断键。用户在可以在需要使用耳机降噪功能时,用两个手指同时按压音量键的第一侧和第二侧,触发主动降噪指令,启用主动降噪功能。Another example: as shown in FIG. 11 , the in-ear wire-controlled headset 200 may include an earphone 210 and a wire-controlled device 220, and the wire-controlled device may include a physical button 221 and a physical button 222, where the physical button 221 is a volume button, and the physical button 222 is for answering /hang up key. When the user needs to use the noise reduction function of the headset, press the first side and the second side of the volume key with two fingers at the same time to trigger the active noise reduction command and enable the active noise reduction function.
在另一种可能的实现方式中,耳机依赖与其连接、且能够对其进行播放控制的终端实现主动降噪功能时,该终端上可以设置有触发主动降噪的虚拟按键。当用户点击所述虚拟按键时,可以触发主动降噪指令,并控制耳机实现主动降噪功能。In another possible implementation manner, when the headset relies on a terminal connected to it and capable of performing playback control to implement the active noise reduction function, the terminal may be provided with a virtual key for triggering active noise reduction. When the user clicks the virtual button, the active noise reduction instruction can be triggered, and the headset can be controlled to realize the active noise reduction function.
需要说明的是,上述耳机和终端可以通过有线或无线的方式连接,本申请实施例对此不作限定。It should be noted that, the foregoing headset and the terminal may be connected in a wired or wireless manner, which is not limited in this embodiment of the present application.
可选地,本申请实施例中所述的终端可以能够与该音频播放设备配合使用实现音频播放功能的手机、平板电脑、可穿戴设备、车载设备、智能电视、笔记本电脑、超级移动个人计算机(ultra-mobile personal computer,UMPC)、上网本、个人数字助理(personal digital assistant,PDA)等设备,本申请实施例对终端的具体类型不作任何限制。Optionally, the terminal described in the embodiments of the present application may be able to cooperate with the audio playback device to use a mobile phone, a tablet computer, a wearable device, a vehicle-mounted device, a smart TV, a notebook computer, a super mobile personal computer ( Ultra-mobile personal computer, UMPC), netbook, personal digital assistant (personal digital assistant, PDA) and other devices, the embodiment of the present application does not impose any restrictions on the specific type of the terminal.
例如:以该终端为手机为例,如图12中的(a)所示,手机300的设置选项中可以包括“主动降噪”选项301,用户在选择“主动降噪”选项301之后,显示如图12中的(b)所示的界面,其中“开启”选项302用于开启主动降噪功能,“关闭”选项303用于关闭主动降噪功能,则当用户选择“开启”选项302后,该手机300即可控制与其连接的耳机启动对应的主动降噪功能进行音频播放。For example, taking the terminal as a mobile phone as an example, as shown in (a) of FIG. 12 , the setting options of the mobile phone 300 may include an “ANC” option 301. After the user selects the “ANC” option 301, the display will display In the interface shown in (b) of FIG. 12 , the “ON” option 302 is used to enable the ANC function, and the “OFF” option 303 is used to disable the ANC function, then when the user selects the “ON” option 302 , the mobile phone 300 can control the headset connected to it to activate the corresponding active noise reduction function to play audio.
在又一种可能的实施例中,耳机依赖与其连接、且能够对其进行播放控制的终端实现主动降噪功能时,该终端上可以设置某一些应用与主动降噪指令的关联关系,当用户启动这些特定的应用时,自动触发主动降噪指令,并控制耳机实现主动降噪功能。In another possible embodiment, when the headset relies on a terminal connected to it and capable of controlling playback to implement the active noise reduction function, the terminal may set the association between certain applications and the active noise reduction command. When the user When these specific applications are started, the active noise cancellation command is automatically triggered, and the headset is controlled to implement the active noise cancellation function.
例如,以该终端为手机为例,用户可以在手机上设置音频软件与主动降噪指令的关联关系。如图13所示,当用户在手机400上使用音频软件播放歌曲,终端400显示音频软件的默认歌单中包括A歌曲401和B歌曲402。用户点击B歌曲402,启动音频软件播放B歌曲402,B歌曲402在音频软件启动时自动触发主动降噪指令,该手机400即可控制与其连接的耳机启动对应的主动降噪功能进行音频播放。For example, taking the terminal as a mobile phone as an example, the user can set the association between the audio software and the active noise reduction instruction on the mobile phone. As shown in FIG. 13 , when the user uses the audio software to play songs on the mobile phone 400 , the terminal 400 displays that the default song list of the audio software includes A song 401 and B song 402 . The user clicks the B song 402, starts the audio software to play the B song 402, and the B song 402 automatically triggers the active noise reduction command when the audio software starts, and the mobile phone 400 can control the headset connected to it to start the corresponding active noise reduction function for audio playback.
图14为本申请实施例提供的主动降噪系统500的示意性框图。该系统500可以适用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。如图14所示,该系统500可以包括参考传感器510(如参考麦克风)、误差传感器520(如误差麦克风)、扬声器530和主动降噪装置540,其中,所述主动降噪装置540包括第一预加重模块541、第二预加重模块542、控制模块543和去加重模块544。FIG. 14 is a schematic block diagram of an active noise reduction system 500 provided by an embodiment of the present application. The system 500 can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. As shown in FIG. 14 , the system 500 may include a reference sensor 510 (eg, a reference microphone), an error sensor 520 (eg, an error microphone), a speaker 530 and an active noise reduction device 540 , wherein the active noise reduction device 540 includes a first A pre-emphasis module 541 , a second pre-emphasis module 542 , a control module 543 and a de-emphasis module 544 .
该参考传感器510通过该第一预加重模块541与该控制模块543的第一输入端连接,该误差传感器520通过该第二预加重模块542与该控制模块543的第二输入端连接,该扬声器530通过该去加重模块544与该控制模块543的输出端连接。该参考传感器510、误差传感器520、扬声器530和主动降噪装置540的设置位置和连接关系可以参考图6。The reference sensor 510 is connected to the first input end of the control module 543 through the first pre-emphasis module 541 , the error sensor 520 is connected to the second input end of the control module 543 through the second pre-emphasis module 542 , the speaker 530 is connected to the output end of the control module 543 through the de-emphasis module 544 . For the arrangement positions and connection relationships of the reference sensor 510 , the error sensor 520 , the speaker 530 and the active noise reduction device 540 , reference may be made to FIG. 6 .
该参考传感器510用于采集该耳机外部的环境噪声,得到第一参考信号x(n);向该第一预加重模块541发送该第一参考信号x(n)。The reference sensor 510 is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first pre-emphasis module 541 .
该第一预加重模块541用于接收来自该参考传感器510的第一参考信号x(n);对该第一参考信号x(n)进行预加重处理,得到目标参考信号x
1(n);向该控制模块543的第一输入端发送该目标参考信号x
1(n)。
The first pre-emphasis module 541 is configured to receive the first reference signal x(n) from the reference sensor 510; perform pre-emphasis processing on the first reference signal x(n) to obtain the target reference signal x 1 (n); The target reference signal x 1 (n) is sent to the first input of the control module 543 .
在一种可能的实现方式中,图15示出了预加重处理的频谱示意图,通过图15可以看到,经过预加重处理后的信号的高频部分的频点能量高于原始信号的高频部分的频点能量,也就是说,经过预加重处理后的信号的高频部分的分辨率高于原始信号的高频部分的 分辨率。因此,能够提高控制模块543处理的信号的高频分辨率,从而提高高频噪声的降噪效果。In a possible implementation manner, FIG. 15 shows a schematic diagram of the spectrum of the pre-emphasis process. It can be seen from FIG. 15 that the frequency point energy of the high-frequency part of the pre-emphasized signal is higher than that of the original signal. Part of the frequency bin energy, that is, the resolution of the high-frequency part of the pre-emphasized signal is higher than the resolution of the high-frequency part of the original signal. Therefore, the high-frequency resolution of the signal processed by the control module 543 can be improved, thereby improving the noise reduction effect of high-frequency noise.
需要说明的是,本申请实施例中所述的高频部分可以理解为起始频率大于或等于预设的频率阈值的第一频段,相应地,低频部分可以理解为截止频率小于该频率阈值的第二频段。It should be noted that the high frequency part described in the embodiments of the present application can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the cutoff frequency less than the frequency threshold. second frequency band.
例如:该第一频率阈值可以为4000赫兹,信号中频率大于或等于4000赫兹的部分称为高频部分,频率小于4000赫兹的部分称为低频部分。For example, the first frequency threshold may be 4000 Hz, the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part, and the part whose frequency is less than 4000 Hz is called the low frequency part.
在一种可能的实现方式中,该第一预加重模块541可以通过以下公式1对该第一参考降噪信号x(n)进行预加重处理,得到目标参考降噪信号x
1(n)。
In a possible implementation manner, the first pre-emphasis module 541 may perform pre-emphasis processing on the first reference noise reduction signal x(n) according to the following formula 1 to obtain the target reference noise reduction signal x 1 (n).
x
1(n)=x(n)-a·x(n-1) 公式1
x 1 (n)=x(n)-a x(n-1) Equation 1
其中,x(n)表示第n时刻的采样值,x(n-1)表示第n-1时刻的采样值,x
1(n)表示该第n时刻的预加重后的采样值,a表示加重系数,且0.9<a<1。
Among them, x(n) represents the sampled value at the nth time, x(n-1) represents the sampled value at the n-1th time, x 1 (n) represents the pre-emphasized sampled value at the nth time, and a represents The weighting factor is 0.9<a<1.
可选地,该第一预加重模块541所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the first pre-emphasis module 541 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第一预加重模块541可以包括第一预加重电路,该第一预加重电路用于实现该第一预加重模块541的功能。In a possible implementation manner, the first pre-emphasis module 541 may include a first pre-emphasis circuit, and the first pre-emphasis circuit is used to implement the function of the first pre-emphasis module 541 .
该误差传感器520用于采集该耳机内部的残留噪声,得到第一误差信号e(n);向该第二预加重模块542发送该第一误差信号e(n)。The error sensor 520 is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second pre-emphasis module 542 .
该第二预加重模块542用于接收来自该误差传感器520的第一误差信号e(n);对该第一误差信号e(n)进行预加重处理,得到目标误差信号e
1(n);向该控制模块543的第二输入端发送该目标误差信号e
1(n)。
The second pre-emphasis module 542 is configured to receive the first error signal e(n) from the error sensor 520; perform pre-emphasis processing on the first error signal e(n) to obtain the target error signal e 1 (n); The target error signal e 1 (n) is sent to the second input of the control module 543 .
需要说明的是,该第二预加重模块542的处理过程可以参考上述第一预加重模块541的处理过程,为避免重复,此处不再赘述。It should be noted that, for the processing procedure of the second pre-emphasis module 542, reference may be made to the above-mentioned processing procedure of the first pre-emphasis module 541, which is not repeated here to avoid repetition.
在一种可能的实现方式中,该第二预加重模块542可以通过以下公式2对该第一误差降噪信号e(n)进行预加重处理,得到目标误差降噪信号e
1(n)。
In a possible implementation manner, the second pre-emphasis module 542 may perform pre-emphasis processing on the first error noise reduction signal e(n) according to the following formula 2 to obtain the target error noise reduction signal e 1 (n).
e
1(n)=e(n)-b·e(n-1) 公式2
e 1 (n)=e(n)-b·e(n-1) Equation 2
其中,e(n)表示第n时刻的采样值,e(n-1)表示第n-1时刻的采样值,e
1(n)表示该第n时刻的预加重后的采样值,b表示加重系数,且0.9<b<1。
Among them, e(n) represents the sampled value at the nth time, e(n-1) represents the sampled value at the n-1th time, e 1 (n) represents the pre-emphasized sampled value at the nth time, and b represents The weighting factor is 0.9<b<1.
可选地,该第二预加重模块542所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the second pre-emphasis module 542 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第二预加重模块542可以包括第二预加重电路,该第二预加重电路用于实现该第二预加重模块542的功能。In a possible implementation manner, the second pre-emphasis module 542 may include a second pre-emphasis circuit, and the second pre-emphasis circuit is configured to implement the function of the second pre-emphasis module 542 .
该控制模块543用于接收来自该第一预加重模块541的该目标参考信号x
1(n)和来自该第二预加重模块542的该目标误差信号e
1(n);根据该目标误差信号e
1(n),对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该去加重模块544发送该第一输出信号y(n)。
The control module 543 is configured to receive the target reference signal x 1 (n) from the first pre-emphasis module 541 and the target error signal e 1 (n) from the second pre-emphasis module 542; according to the target error signal e 1 (n), perform adaptive filtering processing on the target reference signal x 1 (n) to obtain a first output signal y(n); send the first output signal y(n) to the de-emphasis module 544 .
在一种可能的实现方式中,该控制模块543可以通过以下公式3~公式5,根据该目标误差信号e
1(n),对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n)。
In a possible implementation manner, the control module 543 can perform adaptive filtering processing on the target reference signal x 1 (n) according to the target error signal e 1 (n) through the following formulas 3 to 5, to obtain The first output signal y(n).
y(n)=w
T(n)·x
1(n) 公式3
y(n)=w T (n) x 1 (n) Equation 3
e
1(n)=d(n)-y
1(n) 公式4
e 1 (n)=d(n)-y 1 (n) Equation 4
w(n+1)=w(n)+c·e
1(n)·x
1(n) 公式5
w(n+1)=w(n)+c·e 1 (n)·x 1 (n) Equation 5
其中,y
1(n)表示该第n时刻的去加重后的采样值,x
1(n)表示该第n时刻的预加重后的采样值,e
1(n)表示该第n时刻的预加重后的采样值,d(n)表示耳机的外部噪声信号(即噪声源),w(n+1)表示第n+1时刻的滤波器系数,w(n)表示第n时刻的滤波器系数,c表示收敛因子。
Among them, y 1 (n) represents the de-emphasized sample value at the nth time, x 1 (n) represents the pre-emphasis sample value at the nth time, and e 1 (n) represents the pre-emphasis at the nth time. The sampled value after emphasis, d(n) represents the external noise signal (ie noise source) of the earphone, w(n+1) represents the filter coefficient at the n+1th time, w(n) represents the filter at the nth time coefficient, and c represents the convergence factor.
可选地,该控制模块543可以包括自适应滤波器。Optionally, the control module 543 may include an adaptive filter.
需要说明的是,自适应滤波器是指根据环境的改变,使用自适应
算法来改变滤波器的参数和结构的滤波器。一般情况下,不改变自适应滤波器的结构。而自适应滤波器的系数是由自适应
算法更新的时变系数。即其系数自动连续地适应于给定信号,以获得期望响应。自适应滤波器的最重要的特征就在于它能够在未知环境中有效工作,并能够跟踪输入信号的时变特征。
Incidentally, the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter. In general, the structure of the adaptive filter is not changed. The coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response. The most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
可选地,该控制模块543所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the control module 543 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该控制模块543可以包括控制电路,该控制电路用于实现该控制模块543的功能。In a possible implementation manner, the control module 543 may include a control circuit, and the control circuit is used to implement the function of the control module 543 .
可选地,该控制模块543为自适应滤波器时,该自适应滤波器可以采用多种自适应滤波算法,本申请实施例对此不作限定。Optionally, when the control module 543 is an adaptive filter, the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该自适应滤波器可以采用最小均方差算法。In a possible implementation manner, the adaptive filter may use a minimum mean square error algorithm.
该去加重模块544用于接收来自该控制模块543的该第一输出信号y(n);对该第一输出信号y(n)进行去加重处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The de-emphasis module 544 is configured to receive the first output signal y(n) from the control module 543; perform de-emphasis processing on the first output signal y(n) to obtain the target output signal y 1 (n); The speaker sends the target output signal y 1 (n).
在一种可能的实现方式中,该去加重模块544可以通过以下公式6对该第一输出信号y(n)进行去加重处理,得到目标输出信号y
1(n)。
In a possible implementation manner, the de-emphasis module 544 may perform de-emphasis processing on the first output signal y(n) according to the following formula 6 to obtain the target output signal y 1 (n).
y
1(n)=y(n)+d·y(n-1) 公式6
y 1 (n)=y(n)+d·y(n-1) Equation 6
其中,y(n)表示第n时刻的采样值,y(n-1)表示第n-1时刻的采样值,y
1(n)表示该第n时刻的去加重后的采样值,d表示加重系数,且0.9<d<1。
Among them, y(n) represents the sampled value at the nth time, y(n-1) represents the sampled value at the n-1th time, y 1 (n) represents the de-emphasized sampled value at the nth time, and d represents the The aggravation factor, and 0.9<d<1.
可选地,该去加重模块544所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the de-emphasis module 544 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该去加重模块544可以包括去加重电路,该去加重电路用于实现该去加重模块544的功能。In a possible implementation manner, the de-emphasis module 544 may include a de-emphasis circuit, and the de-emphasis circuit is used to implement the function of the de-emphasis module 544 .
该扬声器530用于接收来自该去加重模块544的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker 530 is used for receiving the target output signal y 1 (n) from the de-emphasis module 544; and playing the target output signal y 1 (n).
本申请实施例提供的主动降噪系统,通过预加重模块提高第一参考信号和第一误差信号的高频部分的分辨率,然后输入控制模块进行自适应滤波,并通过去加重模块恢复控制模块输出的第一输出信号的高频部分的分辨率,并控制扬声器进行播放。也就是说,本申请实施例提供的主动降噪系统,通过预加重模块和去加重模块提高控制模块处理的信号的高频分辨率,从而能够提高对高频噪声的降噪效果。In the active noise reduction system provided by the embodiment of the present application, the resolution of the first reference signal and the high-frequency part of the first error signal is improved through the pre-emphasis module, and then input to the control module for adaptive filtering, and the de-emphasis module restores the control module Output the resolution of the high frequency part of the first output signal, and control the speaker to play. That is to say, in the active noise reduction system provided by the embodiments of the present application, the pre-emphasis module and the de-emphasis module improve the high-frequency resolution of the signal processed by the control module, thereby improving the noise reduction effect on high-frequency noise.
需要说明的是,图14仅示例性以本申请实施例提供的主动降噪系统为复合式主动降噪系统为例进行介绍,该主动降噪系统还可以为如图16所示的前馈式主动降噪系统,或 者如图17所示的反馈式主动降噪系统本申请实施例对此不作限定。It should be noted that FIG. 14 only exemplifies the introduction of the active noise reduction system provided by the embodiment of the present application as a composite active noise reduction system, and the active noise reduction system may also be a feedforward type as shown in FIG. 16 . The active noise reduction system, or the feedback active noise reduction system as shown in FIG. 17 is not limited in this embodiment of the present application.
还需要说明的是,当该主动降噪系统为前馈式主动降噪系统或反馈式主动降噪系统时,该主动降噪系统的处理过程可以参考上述图14中所述的复合式主动降噪系统中相应模块的处理过程,为避免重复,此处不再赘述。It should also be noted that when the active noise reduction system is a feedforward active noise reduction system or a feedback active noise reduction system, the processing process of the active noise reduction system may refer to the composite active noise reduction described in FIG. 14 above. The processing process of the corresponding module in the noise system is not repeated here in order to avoid repetition.
图18为本申请实施例提供的主动降噪系统600的示意性框图。该系统600可以应用于音频播放设备,如耳机,并可以适用于音频播放设备的主动降噪场景。如图18所示,该系统500可以包括参考传感器610(如参考麦克风)、误差传感器620(如误差麦克风)、扬声器630和主动降噪装置640,其中,所述主动降噪装置640包括第一低通滤波模块641、第二低通滤波模块642、控制模块643和带宽扩展模块644。FIG. 18 is a schematic block diagram of an active noise reduction system 600 provided by an embodiment of the present application. The system 600 can be applied to audio playback devices, such as headphones, and can be applied to active noise reduction scenarios of audio playback devices. As shown in FIG. 18 , the system 500 may include a reference sensor 610 (eg, a reference microphone), an error sensor 620 (eg, an error microphone), a speaker 630 and an active noise reduction device 640 , wherein the active noise reduction device 640 includes a first A low-pass filtering module 641 , a second low-pass filtering module 642 , a control module 643 and a bandwidth expansion module 644 .
该参考传感器610通过该第一低通滤波模块641与该控制模块643的第一输入端连接,该误差传感器620通过该第二低通滤波模块642与该控制模块643的第二输入端连接,该扬声器630通过该644与该控制模块643的输出端连接。该参考传感器610、误差传感器620、扬声器630和主动降噪装置640的设置位置和连接关系可以参考图6。The reference sensor 610 is connected to the first input terminal of the control module 643 through the first low-pass filter module 641 , the error sensor 620 is connected to the second input terminal of the control module 643 through the second low-pass filter module 642 , The speaker 630 is connected to the output end of the control module 643 through the 644 . For the arrangement positions and connection relationships of the reference sensor 610 , the error sensor 620 , the speaker 630 and the active noise reduction device 640 , reference may be made to FIG. 6 .
该参考传感器610用于采集该耳机外部的环境噪声,得到第一参考信号x(n);向该第一低通滤波模块641发送该第一参考信号x(n)。The reference sensor 610 is used to collect ambient noise outside the earphone to obtain a first reference signal x(n); and send the first reference signal x(n) to the first low-pass filtering module 641 .
该第一低通滤波模块641用于接收来自该参考传感器610的第一参考信号x(n);对该第一参考信号x(n)进行低通滤波处理,得到目标参考信号x
1(n);向该控制模块643的第一输入端发送该目标参考信号x
1(n)。
The first low-pass filtering module 641 is configured to receive the first reference signal x(n) from the reference sensor 610; perform low-pass filtering on the first reference signal x(n) to obtain the target reference signal x 1 (n ); send the target reference signal x 1 (n) to the first input terminal of the control module 643 .
在一种可能的实现方式中,图19示出了低通滤波处理的频谱示意图,通过图19可以看到,经过低通滤波处理后的信号滤除了原始信号中的高频部分,仅包含稳定性更高的低频部分。因此,能够提高控制模块543处理的信号的高频稳定性和鲁棒性,从而提高高频噪声的降噪效果。In a possible implementation manner, FIG. 19 shows a schematic diagram of the frequency spectrum of the low-pass filtering process. It can be seen from FIG. 19 that the low-pass filtering signal has filtered out the high-frequency part in the original signal, and only contains stable The higher frequency low frequency part. Therefore, the high-frequency stability and robustness of the signal processed by the control module 543 can be improved, thereby improving the noise reduction effect of high-frequency noise.
需要说明的是,本申请实施例中所述的高频部分可以理解为起始频率大于或等于预设的频率阈值的第一频段,相应地,低频部分可以理解为截止频率小于该频率阈值的第二频段。It should be noted that the high frequency part described in the embodiments of the present application can be understood as the first frequency band whose starting frequency is greater than or equal to the preset frequency threshold, and correspondingly, the low frequency part can be understood as the cutoff frequency less than the frequency threshold. second frequency band.
例如:该第一频率阈值可以为4000赫兹,信号中频率大于或等于4000赫兹的部分称为高频部分,频率小于4000赫兹的部分称为低频部分。For example, the first frequency threshold may be 4000 Hz, the part of the signal whose frequency is greater than or equal to 4000 Hz is called the high frequency part, and the part whose frequency is less than 4000 Hz is called the low frequency part.
在一种可能的实现方式中,该第一低通滤波模块641具体用于对该第一参考信号x(n)进行下采样,得到该目标参考信号x
1(n)。
In a possible implementation manner, the first low-pass filtering module 641 is specifically configured to downsample the first reference signal x(n) to obtain the target reference signal x 1 (n).
例如:以该x(n)为4KHz的频率宽度,该第一低通滤波模块641具体用于每四个音频采样点抽取一个音频采样点,得到下采样后的x
1(n),其频率宽度为1kHz频宽。
For example: taking the x(n) as the frequency width of 4KHz, the first low-pass filtering module 641 is specifically used to extract an audio sampling point for every four audio sampling points to obtain the down-sampled x 1 (n), whose frequency The width is 1kHz bandwidth.
可选地,该第一低通滤波模块641所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the first low-pass filtering module 641 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第一低通滤波模块641可以包括第一低通滤波电路,该第一低通滤波电路用于实现该第一低通滤波模块641的功能。In a possible implementation manner, the first low-pass filtering module 641 may include a first low-pass filtering circuit, and the first low-pass filtering circuit is used to implement the function of the first low-pass filtering module 641 .
该误差传感器620用于采集该耳机内部的残留噪声,得到第一误差信号e(n);向该第二低通滤波模块642发送该第一误差信号e(n)。The error sensor 620 is used for collecting residual noise inside the earphone to obtain a first error signal e(n); and sending the first error signal e(n) to the second low-pass filtering module 642 .
该第二低通滤波模块642用于接收来自该误差传感器620的第一误差信号e(n);对该第一误差信号e(n)进行低通滤波处理,得到目标误差信号e
1(n);向该控制模块643的第二 输入端发送该目标误差信号e
1(n)。
The second low-pass filtering module 642 is configured to receive the first error signal e(n) from the error sensor 620; perform low-pass filtering on the first error signal e(n) to obtain the target error signal e 1 (n ); send the target error signal e 1 (n) to the second input terminal of the control module 643 .
需要说明的是,该第二低通滤波模块642的处理过程可以参考上述第一低通滤波模块641的处理过程,为避免重复,此处不再赘述。It should be noted that, for the processing procedure of the second low-pass filtering module 642, reference may be made to the processing procedure of the first low-pass filtering module 641, which is not repeated here in order to avoid repetition.
可选地,该第二低通滤波模块642所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the second low-pass filtering module 642 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该第二低通滤波模块642可以包括第二低通滤波电路,该第二低通滤波电路用于实现该第二低通滤波模块642的功能。In a possible implementation manner, the second low-pass filtering module 642 may include a second low-pass filtering circuit, and the second low-pass filtering circuit is used to implement the function of the second low-pass filtering module 642 .
该控制模块643用于接收来自该第一低通滤波模块641的该目标参考信号x
1(n)和来自该第二低通滤波模块642的该目标误差信号e
1(n);根据该目标误差信号e
1(n),对该目标参考信号x
1(n)进行自适应滤波处理,得到第一输出信号y(n);向该644发送该第一输出信号y(n)。
The control module 643 is configured to receive the target reference signal x 1 (n) from the first low-pass filtering module 641 and the target error signal e 1 (n) from the second low-pass filtering module 642; according to the target The error signal e 1 (n) is subjected to adaptive filtering processing on the target reference signal x 1 (n) to obtain the first output signal y(n); the first output signal y(n) is sent to the 644 .
可选地,该控制模块643可以包括自适应滤波器。Optionally, the control module 643 may include an adaptive filter.
需要说明的是,自适应滤波器是指根据环境的改变,使用自适应
算法来改变滤波器的参数和结构的滤波器。一般情况下,不改变自适应滤波器的结构。而自适应滤波器的系数是由自适应
算法更新的时变系数。即其系数自动连续地适应于给定信号,以获得期望响应。自适应滤波器的最重要的特征就在于它能够在未知环境中有效工作,并能够跟踪输入信号的时变特征。
Incidentally, the adaptive filter means in accordance with changes in the environment, adaptive filter parameters and algorithms to alter the structure of the filter. In general, the structure of the adaptive filter is not changed. The coefficients of the adaptive filter is updated by an adaptive algorithm for time varying coefficients. That is, its coefficients are automatically and continuously adapted to a given signal to obtain the desired response. The most important feature of an adaptive filter is that it can work effectively in an unknown environment and can track the time-varying characteristics of the input signal.
可选地,该控制模块643所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the control module 643 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该控制模块643可以包括控制电路,该控制电路用于实现该控制模块643的功能。In a possible implementation manner, the control module 643 may include a control circuit, and the control circuit is used to realize the function of the control module 643 .
可选地,该控制模块643为自适应滤波器时,该自适应滤波器可以采用多种自适应滤波算法,本申请实施例对此不作限定。Optionally, when the control module 643 is an adaptive filter, the adaptive filter may adopt a variety of adaptive filtering algorithms, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该自适应滤波器可以采用最小均方差算法。In a possible implementation manner, the adaptive filter may use a minimum mean square error algorithm.
该带宽扩展模块644用于接收来自该控制模块643的该第一输出信号y(n);对该第一输出信号y(n)进行带宽扩展处理,得到目标输出信号y
1(n);向扬声器发送该目标输出信号y
1(n)。
The bandwidth expansion module 644 is configured to receive the first output signal y(n) from the control module 643; perform bandwidth expansion processing on the first output signal y(n) to obtain the target output signal y 1 (n); The speaker sends the target output signal y 1 (n).
可选地,该带宽扩展模块644可以通过多种方式,对该第一输出信号进行带宽扩展处理,得到目标输出信号,本申请实施例对此不作限定。Optionally, the bandwidth expansion module 644 may perform bandwidth expansion processing on the first output signal in various manners to obtain a target output signal, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该带宽扩展模块644可以通过盲目式高频重建法,对该第一输出信号进行带宽扩展处理,得到目标输出信号。In a possible implementation manner, the bandwidth expansion module 644 may perform bandwidth expansion processing on the first output signal through a blind high-frequency reconstruction method to obtain the target output signal.
可选地,盲目式高频重建法可以包括:线性外推(linear extrapolation,LE)、有效高频带宽扩展(efficient high-frequency bandwidth extension,EHBE)、混合信号外推(hybrid signal extrapolation,HSE)和非线性预测等。Optionally, the blind high-frequency reconstruction method may include: linear extrapolation (LE), efficient high-frequency bandwidth extension (EHBE), hybrid signal extrapolation (HSE) and nonlinear prediction.
需要说明的是,线性外推法是指音频信号的对数幅度谱包络呈近似线性递减关系来进行高频重建,其中,高频重建包括高频部分频域包络和高频部分频谱细节两部分。其中,高频谱包络可以借助幅度谱的线性关系获得,高频谱细节可以通过复制低频带的谐波结构获得。It should be noted that the linear extrapolation method means that the logarithmic amplitude spectral envelope of the audio signal is in an approximately linearly decreasing relationship to perform high-frequency reconstruction, wherein the high-frequency reconstruction includes the frequency domain envelope of the high-frequency part and the spectral details of the high-frequency part. two parts. Among them, the high spectral envelope can be obtained by the linear relationship of the amplitude spectrum, and the high spectral details can be obtained by replicating the harmonic structure of the low frequency band.
在一种可能的实现方式中,该带宽扩展模块644具体用于对低频信号y(n)进行时频变 换得到其谱包络;采用线性最小二乘法将该包络在对数域拟合成一条直线,得到该直线的最佳斜率和截距;将低频部分的频谱信息进行复制得到高频部分的频谱细节;利用拟合直线的斜率对高频谱细节进行包络衰减,完成高频部分的重建,从而得到完整的、包括高频部分和低频部分的信号y
1(n)。
In a possible implementation manner, the bandwidth expansion module 644 is specifically configured to perform time-frequency transformation on the low-frequency signal y(n) to obtain its spectral envelope; use the linear least squares method to fit the envelope in the logarithmic domain as A straight line is used to obtain the best slope and intercept of the straight line; the spectral information of the low-frequency part is copied to obtain the spectral details of the high-frequency part; the envelope attenuation of the high-frequency spectral details is performed by the slope of the fitted straight line to complete the high-frequency part. Reconstruction to obtain a complete signal y 1 (n) including high frequency part and low frequency part.
可选地,该带宽扩展模块644所实现的功能可以通过硬件或软件实现,本申请实施例对此不作限定。Optionally, the function implemented by the bandwidth expansion module 644 may be implemented by hardware or software, which is not limited in this embodiment of the present application.
在一种可能的实现方式中,该带宽扩展模块644可以包括带宽扩展电路,该带宽扩展电路用于实现该带宽扩展模块644的功能。In a possible implementation manner, the bandwidth extension module 644 may include a bandwidth extension circuit, and the bandwidth extension circuit is used to implement the function of the bandwidth extension module 644 .
该扬声器630用于接收来自该带宽扩展模块644的该目标输出信号y
1(n);播放该目标输出信号y
1(n)。
The speaker 630 is used for receiving the target output signal y 1 (n) from the bandwidth expansion module 644; and playing the target output signal y 1 (n).
本申请实施例提供的主动降噪系统,通过第一低通滤波模块滤除第一参考信号中稳定性较差的高频部分和/或通过第二低通滤波模块滤除第一误差信号中稳定性较差的高频部分,只留下第一参考信号和第一误差信号中稳定性较强的低频部分然后输入控制模块进行自适应滤波,并通过带宽扩展模块重建出控制模块输出的第一输出信号的高频部分,得到完整带宽(既包含高频部分也包含低频部分)的目标输出信号,并控制扬声器进行播放。也就是说,通过低通滤波模块和带宽扩展模块提高控制模块处理的信号的高频部分的稳定性和鲁棒性,从而提高高频噪声的降噪效果。In the active noise reduction system provided by the embodiment of the present application, the first low-pass filtering module filters out the high-frequency part with poor stability in the first reference signal and/or the second low-pass filtering module filters out the first error signal. For the high-frequency part with poor stability, only the low-frequency part with strong stability in the first reference signal and the first error signal is left, and then it is input to the control module for adaptive filtering, and the first reference signal output by the control module is reconstructed through the bandwidth expansion module. A high-frequency part of an output signal, obtain a target output signal with a complete bandwidth (including both high-frequency part and low-frequency part), and control the speaker to play. That is, the stability and robustness of the high-frequency part of the signal processed by the control module are improved through the low-pass filtering module and the bandwidth expansion module, thereby improving the noise reduction effect of high-frequency noise.
需要说明的是,图18仅示例性以本申请实施例提供的主动降噪系统为复合式主动降噪系统为例进行介绍,该主动降噪系统还可以为如图20所示的前馈式主动降噪系统,或者如图21所示的反馈式主动降噪系统本申请实施例对此不作限定。It should be noted that FIG. 18 only exemplifies the introduction of the active noise reduction system provided by the embodiment of the present application as a composite active noise reduction system. The active noise reduction system may also be a feedforward type as shown in FIG. 20 . The active noise reduction system, or the feedback active noise reduction system as shown in FIG. 21 is not limited in this embodiment of the present application.
还需要说明的是,当该主动降噪系统为前馈式主动降噪系统或反馈式主动降噪系统时,该主动降噪系统的处理过程可以参考上述图18中所述的复合式主动降噪系统中相应模块的处理过程,为避免重复,此处不再赘述。It should also be noted that when the active noise reduction system is a feedforward active noise reduction system or a feedback active noise reduction system, the processing process of the active noise reduction system may refer to the composite active noise reduction described in FIG. 18 above. The processing process of the corresponding module in the noise system is not repeated here in order to avoid repetition.
上面结合图14至图21介绍了本申请实施例提供的主动降噪系统,下面将结合图22至图23介绍本申请实施例提供的主动降噪方法。The active noise reduction system provided by the embodiments of the present application is described above with reference to FIGS. 14 to 21 , and the active noise reduction method provided by the embodiments of the present application will be described below with reference to FIGS. 22 to 23 .
图22示出了本申请实施例提供的主动降噪方法700的示意性流程图。该方法700可以应用于如图14所示的复合式主动降噪系统500,并由该系统500中的主动降噪装置540执行。该方法700可以包括以下S701~S707。FIG. 22 shows a schematic flowchart of an active noise reduction method 700 provided by an embodiment of the present application. The method 700 can be applied to the composite active noise reduction system 500 as shown in FIG. 14 and executed by the active noise reduction device 540 in the system 500 . The method 700 may include the following S701-S707.
S701,获取参考传感器采集的第一参考信号,该第一参考信号用于表征音频播放设备外部的环境噪声。S701: Acquire a first reference signal collected by a reference sensor, where the first reference signal is used to represent ambient noise outside the audio playback device.
S702,对该第一参考信号进行预加重处理,得到目标参考信号。S702: Perform pre-emphasis processing on the first reference signal to obtain a target reference signal.
S703,获取误差传感器采集的第一误差信号,该第一误差信号用于表征该音频播放设备内部的残留噪声。S703: Acquire a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device.
S704,对该第一误差信号进行预加重处理,得到目标误差信号。S704, perform pre-emphasis processing on the first error signal to obtain a target error signal.
S705,根据该目标误差信号,对该目标参考信号进行滤波处理,得到用于降噪的第一输出信号,该第一输出信号的相位与该目标参考信号的相位相反。S705: Perform filtering processing on the target reference signal according to the target error signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal.
S706,对该第一输出信号进行去加重处理,得到目标输出信号。S706, perform de-emphasis processing on the first output signal to obtain a target output signal.
S707,控制扬声器播放该目标输出信号。S707, controlling the speaker to play the target output signal.
需要说明的是,上述各步骤可以参考上述图14中的主动降噪装置540的各个模块介 绍,为避免重复,此处不再赘述。It should be noted that, for the above steps, reference may be made to the introduction of each module of the active noise reduction device 540 in the above-mentioned FIG. 14 , and to avoid repetition, details are not repeated here.
可选地,该方法700还可以应用于如图16所示的前馈式主动降噪系统500,并由该系统500中的主动降噪装置540执行。具体地,当该方法700应用于前馈式主动降噪系统500时,该方法700包括上述S701~S702和S705~S707。其中,S705包括:对该目标参考信号进行滤波处理,得到该第一输出信号。Optionally, the method 700 can also be applied to the feedforward active noise reduction system 500 shown in FIG. 16 , and executed by the active noise reduction device 540 in the system 500 . Specifically, when the method 700 is applied to the feedforward active noise reduction system 500, the method 700 includes the above-mentioned S701-S702 and S705-S707. Wherein, S705 includes: filtering the target reference signal to obtain the first output signal.
可选地,该方法700还可以应用于如图17所示的反馈式主动降噪系统500,并由该系统500中的主动降噪装置540执行。具体地,当该方法700应用于反馈式主动降噪系统500时,该方法700包括上述S703~S707。其中,S705包括:根据该目标误差信号进行滤波处理,得到该第一输出信号。Optionally, the method 700 can also be applied to the feedback active noise reduction system 500 as shown in FIG. 17 and executed by the active noise reduction device 540 in the system 500 . Specifically, when the method 700 is applied to the feedback active noise reduction system 500, the method 700 includes the above-mentioned S703-S707. Wherein, S705 includes: performing filtering processing according to the target error signal to obtain the first output signal.
图23示出了本申请实施例提供的主动降噪方法800的示意性流程图。该方法800可以应用于如图18所示的复合式主动降噪系统600,并由该系统600中的主动降噪装置640执行。该方法800可以包括以下S801~S807。FIG. 23 shows a schematic flowchart of an active noise reduction method 800 provided by an embodiment of the present application. The method 800 can be applied to the composite active noise reduction system 600 as shown in FIG. 18 and executed by the active noise reduction device 640 in the system 600 . The method 800 may include the following S801-S807.
S801,获取参考传感器采集的第一参考信号,所述第一参考信号用于表征音频播放设备外部的环境噪声。S801: Acquire a first reference signal collected by a reference sensor, where the first reference signal is used to represent ambient noise outside the audio playback device.
S802,对所述第一参考信号进行低通滤波处理,得到目标参考信号。S802: Perform low-pass filtering on the first reference signal to obtain a target reference signal.
S803,获取误差传感器采集的第一误差信号,所述第一误差信号用于表征所述音频播放设备内部的残留噪声。S803: Acquire a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device.
S804,对所述第一误差信号进行低通滤波处理,得到目标误差信号。S804: Perform low-pass filtering on the first error signal to obtain a target error signal.
S805,所述目标误差信号,对所述目标参考信号进行滤波处理,得到用于降噪的第一输出信号,所述第一输出信号的相位与所述目标参考信号的相位相反。S805 , for the target error signal, filter the target reference signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal.
S806,对所述第一输出信号进行带宽扩展处理,得到目标输出信号。S806, performing bandwidth expansion processing on the first output signal to obtain a target output signal.
S807,控制扬声器播放所述目标输出信号。S807, controlling the speaker to play the target output signal.
需要说明的是,上述各步骤可以参考上述图18中的主动降噪装置640的各个模块介绍,为避免重复,此处不再赘述。It should be noted that, for the above steps, reference may be made to the introduction of each module of the active noise reduction device 640 in FIG. 18 , and to avoid repetition, details are not described here.
可选地,该方法800还可以应用于如图16所示的前馈式主动降噪系统600,并由该系统600中的主动降噪装置640执行。具体地,当该方法800应用于前馈式主动降噪系统600时,该方法800包括上述S801~S802和S805~S807。其中,S805包括:对该目标参考信号进行滤波处理,得到该第一输出信号。Optionally, the method 800 can also be applied to the feedforward active noise reduction system 600 as shown in FIG. 16 and executed by the active noise reduction device 640 in the system 600 . Specifically, when the method 800 is applied to the feedforward active noise reduction system 600, the method 800 includes the above-mentioned S801-S802 and S805-S807. Wherein, S805 includes: filtering the target reference signal to obtain the first output signal.
可选地,该方法800还可以应用于如图18所示的反馈式主动降噪系统600,并由该系统600中的主动降噪装置640执行。具体地,当该方法800应用于反馈式主动降噪系统600时,该方法800包括上述S803~S807。其中,S805包括:根据该目标误差信号进行滤波处理,得到该第一输出信号。Optionally, the method 800 can also be applied to the feedback active noise reduction system 600 as shown in FIG. 18 and executed by the active noise reduction device 640 in the system 600 . Specifically, when the method 800 is applied to the feedback active noise reduction system 600, the method 800 includes the above-mentioned S803-S807. Wherein, S805 includes: performing filtering processing according to the target error signal to obtain the first output signal.
上面结合图22和图23介绍了本申请实施例提供的主动降噪方法,下面将结合图24至图25介绍本申请实施例提供的主动降噪装置900。The active noise reduction method provided by the embodiments of the present application is described above with reference to FIGS. 22 and 23 , and the active noise reduction device 900 provided by the embodiments of the present application will be described below with reference to FIGS. 24 to 25 .
需要说明的是,装置900可以为上述系统500实施例和方法700实施例中所述的所述的主动降噪装置,或者可以为上述系统600实施例和方法800实施例中所述的主动降噪装置,本申请实施例对此不作限定。It should be noted that the apparatus 900 may be the active noise reduction apparatus described in the foregoing system 500 embodiment and the method 700 embodiment, or may be the active noise reduction apparatus described in the foregoing system 600 embodiment and method 800 embodiment. noise device, which is not limited in this embodiment of the present application.
可以理解的是,装置900为了实现上述功能,其包含了执行各个功能相应的硬件和/或软件模块。结合本文中所公开的实施例描述的各示例的算法步骤,本申请能够以硬件或 硬件和计算机软件的结合形式来实现。某个功能究竟以硬件还是计算机软件驱动硬件的方式来执行,取决于技术方案的特定应用和设计约束条件。本领域技术人员可以结合实施例对每个特定的应用来使用不同方法来实现所描述的功能,但是这种实现不应认为超出本申请的范围。It can be understood that, in order to implement the above-mentioned functions, the apparatus 900 includes corresponding hardware and/or software modules for executing each function. The present application can be implemented in hardware or a combination of hardware and computer software in conjunction with the algorithm steps of the examples described in conjunction with the embodiments disclosed herein. Whether a function is performed by hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functionality for each particular application in conjunction with the embodiments, but such implementations should not be considered beyond the scope of this application.
本实施例可以根据上述方法示例对装置900进行功能模块的划分,例如,可以对应各个功能划分各个功能模块,也可以将两个或两个以上的功能集成在一个处理模块中。上述集成的模块可以采用硬件的形式实现。需要说明的是,本实施例中对模块的划分是示意性的,仅仅为一种逻辑功能划分,实际实现时可以有另外的划分方式。In this embodiment, the apparatus 900 may be divided into functional modules according to the foregoing method examples. For example, each functional module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The above-mentioned integrated modules can be implemented in the form of hardware. It should be noted that, the division of modules in this embodiment is schematic, and is only a logical function division, and there may be other division manners in actual implementation.
在采用对应各个功能划分各个功能模块的情况下,图24示出了上述各实施例中涉及的主动降噪装置的一种可能的组成示意图,如图24所示,该装置900可以包括:收发单元910和处理单元920。In the case where each functional module is divided according to each function, FIG. 24 shows a possible schematic diagram of the composition of the active noise reduction device involved in the above embodiments. As shown in FIG. 24 , the device 900 may include: unit 910 and processing unit 920.
其中,处理单元920可以控制收发单元910实现上述方法700实施例或800中所述的方法,和/或用于本文所描述的技术的其他过程。Wherein, the processing unit 920 may control the transceiver unit 910 to implement the method described in the foregoing method 700 embodiment or 800, and/or other processes for the techniques described herein.
需要说明的是,上述方法实施例涉及的各步骤的所有相关内容均可以援引到对应功能模块的功能描述,在此不再赘述。It should be noted that, all relevant contents of the steps involved in the above method embodiments can be cited in the functional description of the corresponding functional module, which will not be repeated here.
本实施例提供的装置900用于执行上述方法700和/或方法800,因此可以达到与上述实现方法相同的效果。The apparatus 900 provided in this embodiment is used to execute the above-mentioned method 700 and/or the method 800, and thus can achieve the same effect as the above-mentioned implementation method.
在一种可能的实现方式中,装置900为主动降噪装置,对应的,处理单元910可以包括第一预加重模块541和/或第二预加重模块542、控制模块543和去加重模块544;或者,处理单元310可以第一低通滤波模块641和/或第二低通滤波模块642、控制模块643和带宽扩展模块644。In a possible implementation manner, the apparatus 900 is an active noise reduction apparatus, and correspondingly, the processing unit 910 may include a first pre-emphasis module 541 and/or a second pre-emphasis module 542, a control module 543 and a de-emphasis module 544; Alternatively, the processing unit 310 may have a first low-pass filtering module 641 and/or a second low-pass filtering module 642 , a control module 643 and a bandwidth expansion module 644 .
在采用集成的单元的情况下,装置900可以包括处理单元、存储单元和通信单元。其中,处理单元可以用于对装置900的动作进行控制管理,例如,可以用于支持装置900执行上述各个单元执行的步骤。存储单元可以用于支持装置900执行存储程序代码和数据等。通信单元可以用于支持装置900与其他设备的通信。Where an integrated unit is employed, the apparatus 900 may include a processing unit, a storage unit, and a communication unit. The processing unit may be used to control and manage the actions of the apparatus 900, for example, may be used to support the apparatus 900 to perform the steps performed by the above-mentioned units. The storage unit may be used to support the execution of the apparatus 900 to store program codes, data, and the like. The communication unit may be used to support the communication of the apparatus 900 with other devices.
其中,处理单元可以是处理器或控制器。其可以实现或执行结合本申请公开内容所描述的各种示例性的逻辑方框,模块和电路。处理器也可以是实现计算功能的组合,例如包含一个或多个微处理器组合,数字信号处理(digital signal processing,DSP)和微处理器的组合等等。存储单元可以是存储器。通信单元具体可以为射频电路、蓝牙芯片、Wi-Fi芯片等与其他电子设备交互的设备。The processing unit may be a processor or a controller. It may implement or execute the various exemplary logical blocks, modules and circuits described in connection with this disclosure. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, and the like. The storage unit may be a memory. The communication unit may specifically be a device that interacts with other electronic devices, such as a radio frequency circuit, a Bluetooth chip, and a Wi-Fi chip.
在一种可能的实现方式中,本实施例所涉及的装置900可以为具有图25所示结构的主动降噪装置1000,该装置1000包括处理器1010和收发器1020,该处理器1010和收发器1020通过内部连接通路互相通信。图25中的处理单元920所实现的相关功能可以由处理器1010来实现,收发单元910所实现的相关功能可以由处理器1010控制收发器1020来实现。In a possible implementation manner, the apparatus 900 involved in this embodiment may be an active noise reduction apparatus 1000 having the structure shown in FIG. 25 , the apparatus 1000 includes a processor 1010 and a transceiver 1020 , the processor 1010 and the transceiver The devices 1020 communicate with each other through internal connection paths. The related functions implemented by the processing unit 920 in FIG. 25 can be implemented by the processor 1010 , and the related functions implemented by the transceiver unit 910 can be implemented by the processor 1010 controlling the transceiver 1020 .
可选地,该装置1000还可以包括存储器1030,该处理器1010、该收发器1020和该存储器1030通过内部连接通路互相通信。图24中所述的存储单元所实现的相关功能可以由存储器1030来实现。Optionally, the apparatus 1000 may further include a memory 1030, and the processor 1010, the transceiver 1020 and the memory 1030 communicate with each other through an internal connection path. The related functions implemented by the storage unit described in FIG. 24 may be implemented by the memory 1030 .
本实施例还提供一种计算机存储介质,该计算机存储介质中存储有计算机指令,当该 计算机指令在电子设备上运行时,使得电子设备执行上述相关方法步骤实现上述实施例中的主动降噪方法。This embodiment also provides a computer storage medium, where computer instructions are stored in the computer storage medium, and when the computer instructions are executed on the electronic device, the electronic device executes the above-mentioned relevant method steps to realize the active noise reduction method in the above-mentioned embodiment. .
本实施例还提供了一种计算机程序产品,当该计算机程序产品在计算机上运行时,使得计算机执行上述相关步骤,以实现上述实施例中的主动降噪方法。This embodiment also provides a computer program product, which when the computer program product runs on the computer, causes the computer to execute the above-mentioned relevant steps, so as to realize the active noise reduction method in the above-mentioned embodiment.
另外,本申请的实施例还提供一种装置,这个装置具体可以是芯片,组件或模块,该装置可包括相连的处理器和存储器;其中,存储器用于存储计算机执行指令,当装置运行时,处理器可执行存储器存储的计算机执行指令,以使芯片执行上述各方法实施例中的主动降噪方法。In addition, the embodiments of the present application also provide an apparatus, which may specifically be a chip, a component or a module, and the apparatus may include a connected processor and a memory; wherein, the memory is used to store computer execution instructions, and when the apparatus is running, The processor can execute the computer-executable instructions stored in the memory, so that the chip executes the active noise reduction method in the foregoing method embodiments.
图26示出了一种芯片1100的结构示意图。芯片1100包括一个或多个处理器1110以及接口电路1120。可选的,所述芯片1100还可以包含总线1130。其中:FIG. 26 shows a schematic structural diagram of a chip 1100 . Chip 1100 includes one or more processors 1110 and interface circuits 1120 . Optionally, the chip 1100 may further include a bus 1130 . in:
处理器1110可能是一种集成电路芯片,具有信号的处理能力。在实现过程中,上述方法的各步骤可以通过处理器1110中的硬件的集成逻辑电路或者软件形式的指令完成。上述的处理器1110可以是通用处理器、DSP、ASIC、FPGA或者其它可编程逻辑器件、分立门或者晶体管逻辑器件、分立硬件组件。可以实现或者执行本申请实施例中的公开的各方法、步骤。通用处理器可以是微处理器或者该处理器也可以是任何常规的处理器等。The processor 1110 may be an integrated circuit chip with signal processing capability. In the implementation process, each step of the above-mentioned method can be completed by an integrated logic circuit of hardware in the processor 1110 or an instruction in the form of software. The aforementioned processor 1110 may be a general purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware components. Various methods and steps disclosed in the embodiments of this application can be implemented or executed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.
接口电路1120可以用于雷达信号的发送或者接收,处理器1110可以利用接口电路1120接收的雷达信号进行加工,可以将加工完成信息通过接口电路1120发送出去。The interface circuit 1120 can be used for transmitting or receiving radar signals. The processor 1110 can process the radar signals received by the interface circuit 1120 , and can send the processing completion information through the interface circuit 1120 .
可选的,芯片还包括存储器,存储器可以包括只读存储器和随机存取存储器,并向处理器提供操作指令和数据。存储器的一部分还可以包括非易失性随机存取存储器(non-volatile random access memory,NVRAM)。Optionally, the chip further includes a memory, which may include a read-only memory and a random access memory, and provides operation instructions and data to the processor. A portion of the memory may also include non-volatile random access memory (NVRAM).
可选的,存储器存储了可执行软件模块或者数据结构,处理器可以通过调用存储器存储的操作指令(该操作指令可存储在操作系统中),执行相应的操作。Optionally, the memory stores executable software modules or data structures, and the processor may execute corresponding operations by calling operation instructions stored in the memory (the operation instructions may be stored in the operating system).
可选的,芯片可以使用在本申请实施例涉及的主动降噪系统中。可选的,接口电路1120可用于输出处理器1110的执行结果。关于本申请的一个或多个实施例提供的主动降噪方法可参考前述各个实施例,这里不再赘述。Optionally, the chip may be used in the active noise reduction system involved in the embodiments of the present application. Optionally, the interface circuit 1120 may be used to output the execution result of the processor 1110 . For the active noise reduction method provided by one or more embodiments of the present application, reference may be made to the foregoing embodiments, which will not be repeated here.
需要说明的,处理器1110、接口电路1120各自对应的功能既可以通过硬件设计实现,也可以通过软件设计来实现,还可以通过软硬件结合的方式来实现,这里不作限制。It should be noted that the respective functions of the processor 1110 and the interface circuit 1120 can be implemented by hardware design, software design, or a combination of software and hardware, which is not limited here.
其中,本实施例提供的主动降噪装置、计算机存储介质、计算机程序产品或芯片均用于执行上文所提供的对应的方法,因此,其所能达到的有益效果可参考上文所提供的对应的方法中的有益效果,此处不再赘述。Wherein, the active noise reduction device, computer storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved may refer to the above provided. The beneficial effects in the corresponding method will not be repeated here.
应理解,在本申请的各种实施例中,上述各过程的序号的大小并不意味着执行顺序的先后,各过程的执行顺序应以其功能和内在逻辑确定,而不应对本申请实施例的实施过程构成任何限定。It should be understood that, in various embodiments of the present application, the size of the sequence numbers of the above-mentioned processes does not mean the sequence of execution, and the execution sequence of each process should be determined by its functions and internal logic, and should not be dealt with in the embodiments of the present application. implementation constitutes any limitation.
本领域普通技术人员可以意识到,结合本文中所公开的实施例描述的各示例的单元及算法步骤,能够以电子硬件、或者计算机软件和电子硬件的结合来实现。这些功能究竟以硬件还是软件方式来执行,取决于技术方案的特定应用和设计约束条件。专业技术人员可以对每个特定的应用来使用不同方法来实现所描述的功能,但是这种实现不应认为超出本申请的范围。Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may implement the described functionality using different methods for each particular application, but such implementations should not be considered beyond the scope of this application.
所属领域的技术人员可以清楚地了解到,为描述的方便和简洁,上述描述的系统、装 置和单元的具体工作过程,可以参考前述方法实施例中的对应过程,在此不再赘述。Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described systems, devices and units can refer to the corresponding processes in the foregoing method embodiments, and will not be repeated here.
在本申请所提供的几个实施例中,应该理解到,所揭露的系统、装置和方法,可以通过其它的方式实现。例如,以上所描述的装置实施例仅仅是示意性的,例如,所述单元的划分,仅仅为一种逻辑功能划分,实际实现时可以有另外的划分方式,例如多个单元或组件可以结合或者可以集成到另一个系统,或一些特征可以忽略,或不执行。另一点,所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口,装置或单元的间接耦合或通信连接,可以是电性,机械或其它的形式。In the several embodiments provided in this application, it should be understood that the disclosed system, apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. On the other hand, the shown or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, indirect coupling or communication connection of devices or units, and may be in electrical, mechanical or other forms.
所述作为分离部件说明的单元可以是或者也可以不是物理上分开的,作为单元显示的部件可以是或者也可以不是物理单元,即可以位于一个地方,或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部单元来实现本实施例方案的目的。The units described as separate components may or may not be physically separated, and components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution in this embodiment.
另外,在本申请各个实施例中的各功能单元可以集成在一个处理单元中,也可以是各个单元单独物理存在,也可以两个或两个以上单元集成在一个单元中。In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.
所述功能如果以软件功能单元的形式实现并作为独立的产品销售或使用时,可以存储在一个计算机可读取存储介质中。基于这样的理解,本申请的技术方案本质上或者说对现有技术做出贡献的部分或者该技术方案的部分可以以软件产品的形式体现出来,该计算机软件产品存储在一个存储介质中,包括若干指令用以使得一台计算机设备(可以是个人计算机,服务器,或者网络设备等)执行本申请各个实施例所述方法的全部或部分步骤。而前述的存储介质包括:U盘、移动硬盘、只读存储器(Read-Only Memory,ROM)、随机存取存储器(Random Access Memory,RAM)、磁碟或者光盘等各种可以存储程序代码的介质。The functions, if implemented in the form of software functional units and sold or used as independent products, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution, and the computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk and other media that can store program codes .
以上所述,仅为本申请的具体实施方式,但本申请的保护范围并不局限于此,任何熟悉本技术领域的技术人员在本申请揭露的技术范围内,可轻易想到变化或替换,都应涵盖在本申请的保护范围之内。因此,本申请的保护范围应以所述权利要求的保护范围为准。The above are only specific embodiments of the present application, but the protection scope of the present application is not limited to this. should be covered within the scope of protection of this application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.
Claims (14)
- 一种主动降噪方法,其特征在于,包括:An active noise reduction method, comprising:获取参考传感器采集的第一参考信号,所述第一参考信号用于表征音频播放设备外部的环境噪声,所述参考传感器设置在所述音频播放设备的外部;acquiring a first reference signal collected by a reference sensor, where the first reference signal is used to represent ambient noise outside the audio playback device, and the reference sensor is provided outside the audio playback device;对所述第一参考信号进行预加重处理,得到目标参考信号;performing pre-emphasis processing on the first reference signal to obtain a target reference signal;对所述目标参考信号进行滤波处理,得到用于降噪的第一输出信号,所述第一输出信号的相位与所述目标参考信号的相位相反;Filtering the target reference signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal;对所述第一输出信号进行去加重处理,得到目标输出信号;performing de-emphasis processing on the first output signal to obtain a target output signal;控制扬声器播放所述目标输出信号。The speaker is controlled to play the target output signal.
- 根据权利要求1所述的方法,其特征在于,所述方法还包括:The method according to claim 1, wherein the method further comprises:获取误差传感器采集的第一误差信号,所述第一误差信号用于表征所述音频播放设备内部的残留噪声,所述误差传感器设置在所述音频播放设备的内部;acquiring a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device, and the error sensor is arranged inside the audio playback device;对所述第一误差信号进行预加重处理,得到目标误差信号;performing pre-emphasis processing on the first error signal to obtain a target error signal;所述对所述目标参考信号进行滤波处理,得到用于降噪的第一输出信号,包括:The filtering process on the target reference signal to obtain a first output signal for noise reduction, including:根据所述目标误差信号,对所述目标参考信号进行滤波处理,得到所述第一输出信号。According to the target error signal, filtering is performed on the target reference signal to obtain the first output signal.
- 根据权利要求2所述的方法,其特征在于,所述根据所述目标误差信号,对所述目标参考信号进行滤波处理,得到所述第一输出信号,包括:The method according to claim 2, wherein filtering the target reference signal according to the target error signal to obtain the first output signal comprises:采用最小均方误差算法,根据所述目标误差信号,对所述目标参考信号进行滤波处理,得到所述第一输出信号。A minimum mean square error algorithm is used to filter the target reference signal according to the target error signal to obtain the first output signal.
- 一种主动降噪方法,其特征在于,包括:An active noise reduction method, comprising:获取误差传感器采集的第一误差信号,所述第一误差信号用于表征音频播放设备内部的残留噪声,所述误差传感器设置在所述音频播放设备的内部;acquiring a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device, and the error sensor is arranged inside the audio playback device;对所述第一误差信号进行预加重处理,得到目标误差信号;performing pre-emphasis processing on the first error signal to obtain a target error signal;根据所述目标误差信号进行滤波处理,得到用于降噪的第一输出信号,所述第一输出信号的相位与所述目标参考信号的相位相反;Perform filtering processing according to the target error signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal;对所述第一输出信号进行去加重处理,得到目标输出信号;performing de-emphasis processing on the first output signal to obtain a target output signal;控制扬声器播放所述目标输出信号。The speaker is controlled to play the target output signal.
- 一种主动降噪方法,其特征在于,包括:An active noise reduction method, comprising:获取参考传感器采集的第一参考信号,所述第一参考信号用于表征音频播放设备外部的环境噪声,所述参考传感器设置在所述音频播放设备的外部;acquiring a first reference signal collected by a reference sensor, where the first reference signal is used to represent ambient noise outside the audio playback device, and the reference sensor is provided outside the audio playback device;对所述第一参考信号进行低通滤波处理,得到目标参考信号;performing low-pass filtering processing on the first reference signal to obtain a target reference signal;对所述目标参考信号进行滤波处理,得到用于降噪的第一输出信号,所述第一输出信号的相位与所述目标参考信号的相位相反;Filtering the target reference signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal;对所述第一输出信号进行带宽扩展处理,得到目标输出信号;performing bandwidth expansion processing on the first output signal to obtain a target output signal;控制扬声器播放所述目标输出信号。The speaker is controlled to play the target output signal.
- 根据权利要求5所述的方法,其特征在于,所述方法还包括:The method according to claim 5, wherein the method further comprises:获取误差传感器采集的第一误差信号,所述第一误差信号用于表征所述音频播放设备内部的残留噪声,所述误差传感器设置在所述音频播放设备的内部;acquiring a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device, and the error sensor is arranged inside the audio playback device;对所述第一误差信号进行低通滤波处理,得到目标误差信号;performing low-pass filtering processing on the first error signal to obtain a target error signal;所述对所述目标参考信号进行滤波处理,得到用于降噪的第一输出信号,包括:The filtering process on the target reference signal to obtain a first output signal for noise reduction, including:所述目标误差信号,对所述目标参考信号进行滤波处理,得到所述第一输出信号。For the target error signal, filter the target reference signal to obtain the first output signal.
- 根据权利要求6所述的方法,其特征在于,The method of claim 6, wherein:所述对所述第一参考信号进行低通滤波处理,得到目标参考信号,包括:The performing low-pass filtering processing on the first reference signal to obtain a target reference signal includes:对所述第一参考信号进行下采样,得到所述目标参考信号;down-sampling the first reference signal to obtain the target reference signal;所述对所述第一误差信号进行低通滤波处理,得到目标误差信号,包括;The performing low-pass filtering processing on the first error signal to obtain a target error signal, including:对所述第一误差信号进行下采样,得到所述目标误差信号。Down-sampling the first error signal to obtain the target error signal.
- 根据权利要求5至7中任一项所述的方法,其特征在于,所述对所述第一输出信号进行带宽扩展处理,得到目标输出信号,包括:The method according to any one of claims 5 to 7, wherein the performing bandwidth extension processing on the first output signal to obtain a target output signal comprises:采用线性外推法,对所述第一输出信号进行带宽扩展处理,得到所述目标输出信号。Using a linear extrapolation method, the bandwidth expansion process is performed on the first output signal to obtain the target output signal.
- 一种主动降噪方法,其特征在于,包括:An active noise reduction method, comprising:获取误差传感器采集的第一误差信号,所述第一误差信号用于表征音频播放设备内部的残留噪声,所述误差传感器设置在所述音频播放设备的内部;acquiring a first error signal collected by an error sensor, where the first error signal is used to represent residual noise inside the audio playback device, and the error sensor is arranged inside the audio playback device;对所述第一误差信号进行低通滤波处理,得到目标误差信号;performing low-pass filtering processing on the first error signal to obtain a target error signal;根据所述目标误差信号进行滤波处理,得到用于降噪的第一输出信号,所述第一输出信号的相位与所述目标参考信号的相位相反;Perform filtering processing according to the target error signal to obtain a first output signal for noise reduction, where the phase of the first output signal is opposite to that of the target reference signal;对所述第一输出信号进行带宽扩展处理,得到目标输出信号;performing bandwidth expansion processing on the first output signal to obtain a target output signal;控制扬声器播放所述目标输出信号。The speaker is controlled to play the target output signal.
- 一种主动降噪装置,其特征在于,所述装置包括用于执行权利要求1至9中任一项所述的方法的单元。An active noise reduction device, characterized in that the device comprises a unit for performing the method of any one of claims 1 to 9.
- 一种芯片装置,包括至少一个处理器以及接口电路,所述接口电路用于为所述至少一个处理器提供数据、指令或者信息的发送和/或接收,其特征在于,当所述至少一个处理器执行程序代码或者指令时,实现权利要求1至9中任一项所述的方法。A chip device, comprising at least one processor and an interface circuit, wherein the interface circuit is used to provide the at least one processor with sending and/or receiving of data, instructions or information, characterized in that when the at least one processing When the computer executes the program code or instructions, the method of any one of claims 1 to 9 is implemented.
- 一种音频播放设备,其特征在于,所述音频播放设备包括权利要求11所述的芯片装置。An audio playback device, characterized in that, the audio playback device comprises the chip device of claim 11 .
- 一种计算机可读存储介质,用于存储计算机程序,其特征在于,所述计算机程序包括用于实现权利要求1至9中任一项所述的方法的指令。A computer-readable storage medium for storing a computer program, wherein the computer program includes instructions for implementing the method of any one of claims 1 to 9.
- 一种计算机程序产品,所述计算机程序产品中包含指令,其特征在于,当所述指令在计算机或处理器上运行时,使得所述计算机或所述处理器实现权利要求1至9中任一项所述的方法。A computer program product comprising instructions, characterized in that, when the instructions are executed on a computer or a processor, the computer or the processor is made to implement any one of claims 1 to 9 method described in item.
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