WO2020097828A1

WO2020097828A1 - Echo cancellation method, delay estimation method, echo cancellation apparatus, delay estimation apparatus, storage medium, and device

Info

Publication number: WO2020097828A1
Application number: PCT/CN2018/115443
Authority: WO
Inventors: 陈岩
Original assignee: 深圳市欢太科技有限公司; Oppo广东移动通信有限公司
Priority date: 2018-11-14
Filing date: 2018-11-14
Publication date: 2020-05-22
Also published as: CN113170024B; CN113170024A

Abstract

An echo cancellation method and a delay estimation method. The delay estimation method estimates an echo path delay of an electronic device, so as to use the echo path delay to perform echo estimation during a call, thereby cancelling an echo, achieving the purpose of improving the speech quality.

Description

Echo cancellation method, delay estimation method, device, storage medium and equipment

Technical field

The present application belongs to the technical field of audio processing, and particularly relates to an echo cancellation method, a delay estimation method, a device, a storage medium, and equipment.

Background technique

The echo is due to the acoustic loop between the speaker and the microphone. During a call, the audio signal of the far-end device is transmitted to the near-end device through the communication connection, released by the speaker of the near-end device, collected by the microphone after passing through the acoustic circuit between the speaker and the microphone, and then transmitted back to the far end through the communication connection Device, so that the user of the remote device will hear his own echo.

Summary of the invention

Embodiments of the present application provide an echo cancellation method, delay estimation method, device, storage medium, and equipment, which can improve call quality.

In a first aspect, an embodiment of the present application provides an echo cancellation method, which is applied to an electronic device and includes:

Obtain the far-end audio signal from the remote device;

Acquiring a near-end audio signal corresponding to the far-end audio signal through a microphone;

Performing echo estimation according to the echo path delay of the electronic device and the far-end audio signal to obtain a first echo signal;

Subtracting the first echo signal from the near-end audio signal to obtain a first residual audio signal;

Wherein, the delay of the echo path is estimated according to a preset frequency sweep signal and a delayed frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal.

In a second aspect, an embodiment of the present application provides a delay estimation method, which is applied to an electronic device and includes:

Providing a preset frequency sweep signal to the speaker to play sound through the speaker;

Collecting sound through a microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal;

Estimating the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal to obtain an operation result;

Transforming the operation result from the time domain to the frequency domain, and determining the frequency at the maximum amplitude of the operation result;

The echo path delay of the electronic device is estimated according to the frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.

In a third aspect, an embodiment of the present application provides an echo cancellation device, which is applied to an electronic device and includes:

The first obtaining module is used to obtain remote audio signals from the remote device;

A second obtaining module, configured to obtain a near-end audio signal corresponding to the far-end audio signal through a microphone;

An echo estimation module, configured to perform echo estimation based on the echo path delay of the electronic device and the far-end audio signal to obtain a first echo signal;

An echo cancellation module, configured to subtract the first echo signal from the near-end audio signal to obtain a first residual audio signal;

According to a fourth aspect, an embodiment of the present application provides a delay estimation device, which is applied to an electronic device and includes:

The signal playing module is used to provide a preset frequency sweep signal to the speaker to play sound through the speaker;

A signal collection module for collecting sound through a microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal;

A multiplication module, used to estimate the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiply the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, Get the operation result;

A frequency determination module, configured to transform the operation result from the time domain to the frequency domain, and determine the frequency at the maximum amplitude of the operation result;

The delay estimation module is used to estimate the echo path delay of the electronic device according to the frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.

According to a fifth aspect, an embodiment of the present application provides a storage medium on which a computer program is stored, wherein, when the computer program is executed on a computer, the computer is caused to execute the echo cancellation method provided in the first aspect of the embodiment , Or cause the computer to execute the delay estimation method provided in the second aspect of this embodiment.

According to a sixth aspect, an embodiment of the present application provides an electronic device, including a memory and a processor, and the processor is used to execute a computer program by calling a computer program stored in the memory:

Obtain the far-end audio signal from the remote device;

According to a seventh aspect, an embodiment of the present application provides an electronic device, including a memory and a processor, where the processor invokes a computer program stored in the memory to execute:

By using the delay estimation method provided by this embodiment to estimate the echo path delay of the electronic device, the echo cancellation method provided by this embodiment can be used to estimate the echo during the call, thereby eliminating the echo, To achieve the purpose of improving call quality.

BRIEF DESCRIPTION

The technical solution of the present invention and its beneficial effects will be apparent through the detailed description of the specific embodiments of the present invention with reference to the accompanying drawings.

FIG. 1 is a schematic flowchart of an echo cancellation method provided by an embodiment of the present application.

2 is a schematic diagram of establishing a communication connection between an electronic device serving as a near-end device and other electronic devices serving as a remote device in an embodiment of the present application.

FIG. 3 is a schematic diagram of collecting near-end audio signals through a microphone in an embodiment of the present application.

4 is another schematic flowchart of an echo cancellation method provided by an embodiment of the present application.

FIG. 5 is a schematic diagram of an echo cancellation mode configuration interface provided in an embodiment of the present application.

FIG. 6 is a schematic flowchart of a delay estimation method provided by an embodiment of the present application.

7 is a schematic structural diagram of an echo cancellation device provided by an embodiment of the present application.

FIG. 8 is a schematic structural diagram of a delay estimation device provided by an embodiment of the present application.

9 is a schematic structural diagram of an electronic device provided by an embodiment of the present application.

10 is another schematic structural diagram of an electronic device provided by an embodiment of the present application.

detailed description

Please refer to the drawings, where the same component symbols represent the same components. The principle of the present invention is illustrated by implementation in an appropriate computing environment. The following description is based on the illustrated specific embodiments of the present invention, which should not be construed as limiting other specific embodiments of the present invention that are not detailed herein.

Please refer to FIG. 1, which is a schematic flowchart of an echo cancellation method provided by an embodiment of the present application. The echo cancellation method can be applied to electronic equipment. The process of the echo cancellation method may include:

In 101, a far-end audio signal is obtained from a far-end device.

Referring to FIG. 2, the electronic device and other electronic devices establish a communication connection based on the network, and based on the communication connection, and the respective microphones and speakers, the electronic device and other electronic devices can interact with audio signals, for example, can make voice calls.

It should be noted that the microphone and the speaker may be independent devices externally connected to the electronic device, or may be two devices disposed within the electronic device, such as a microphone and a speaker built in the electronic device such as a smartphone and a tablet computer.

In this embodiment, the electronic device is recorded as a near-end device, and other electronic devices are recorded as a far-end device. First, the electronic device can obtain the remote audio signal from the remote device. For example, the remote device collects the speech sound of the remote user through the microphone to obtain the audio signal of the speech sound of the remote user, and transmits the audio signal of the speech sound of the remote user to the electronic device, and the electronic device The audio signal of the user's voice is recorded as the far-end audio signal.

In addition, the electronic device also provides the acquired far-end audio signal to the speaker, and plays the sound of the far-end audio signal through the speaker, so that the near-end user can hear the far-end user's voice.

In 102, a near-end audio signal corresponding to a far-end audio signal is obtained through a microphone.

For example, referring to FIG. 3, the electronic device collects sound through a microphone. In addition to collecting the speech sound of the near-end user, the sound of the far-end audio signal played by the speaker (that is, the user's speech sound of the plan) The collected audio signal including both the near-end user's voice and the sound of the speaker playing the far-end audio signal is recorded as the near-end audio signal.

It is easy to understand that since the near-end audio signal includes the sound of the speaker playing the far-end audio signal, if the near-end audio signal is directly transmitted to the far-end device, the far-end user will hear his own “echo”. For this reason, in this embodiment, in order to avoid passing the "echo" to the far-end user, the echo needs to be canceled and transferred to 103.

In 103, the echo estimation is performed according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal.

It should be noted that in this embodiment, the transmission duration of the echo from the speaker to the microphone is recorded as the echo path delay. The echo path delay is obtained before 101 according to the preset frequency sweep signal and the delay frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal, and the delay estimation method provided in the embodiment of the present application is used to estimate the delay.

In this embodiment, after acquiring the near-end audio signal corresponding to the far-end audio signal through the microphone, the electronic device further performs echo estimation according to the pre-obtained echo path delay and the far-end audio signal, and then estimates the estimated echo signal at this time Recorded as the first echo signal.

In 104, the first echo signal is subtracted from the near-end audio signal to obtain a first residual audio signal.

In this embodiment, after estimating the first echo signal, the electronic device can subtract the first echo signal from the near-end audio signal to eliminate the echo in the near-end audio signal and reduce the near-end audio signal at this time The residual audio signal obtained by removing the first echo signal is recorded as the first residual audio signal.

As can be seen from the above, in this embodiment, the electronic device as the near-end device can obtain the far-end audio signal from the far-end device, and obtain the near-end audio signal corresponding to the far-end audio signal through the microphone; then, according to the echo path delay And the far-end audio signal performs echo estimation to obtain a first echo signal, and then subtracts the first echo signal from the near-end audio signal to eliminate the echo in the near-end audio signal to obtain a first residual audio signal. Wherein, the echo path delay is obtained in advance by delay estimation according to the preset frequency sweep signal and the delay sweep signal collected by the microphone corresponding to the preset frequency sweep signal. Therefore, when this solution is adopted, as long as the echo path is obtained Delay, the echo path delay can be used to estimate the echo during the call, so as to eliminate the echo and achieve the purpose of improving the quality of the call.

Please refer to FIG. 4, which is another schematic flowchart of an echo cancellation method according to an embodiment of the present application. The echo cancellation method can be applied to electronic equipment. The process of the echo cancellation method may include:

In 201, the electronic device obtains a remote audio signal from the remote device.

In 202, the electronic device obtains the near-end audio signal corresponding to the far-end audio signal through the microphone.

For example, referring to FIG. 3, the electronic device collects sound through the microphone. In addition to collecting the speech sound of the near-end user, the sound of the speaker playing the far-end audio signal (that is, the speech sound of the far-end user) is also collected. The collected audio signal including both the near-end user's voice and the sound of the speaker playing the far-end audio signal is recorded as the near-end audio signal.

It is easy to understand that since the near-end audio signal includes the sound of the speaker playing the far-end audio signal, if the near-end audio signal is directly transmitted to the far-end device, the far-end user will hear his own “echo”. For this reason, in this embodiment, in order to avoid passing the "echo" to the far-end user, the echo needs to be canceled and transferred to 203.

In 203, the electronic device determines the current echo cancellation mode, where the echo cancellation mode includes the first echo cancellation mode or the second echo cancellation mode, if the current echo cancellation mode is the first echo cancellation mode, then go to 204, if If the current echo cancellation mode is the second echo cancellation mode, go to 206.

It should be noted that two echo cancellation modes are provided in this embodiment, which are respectively denoted as a first echo cancellation mode and a second echo cancellation mode. The processing speed of the first echo cancellation mode is faster than the processing speed of the second echo cancellation mode. The current echo cancellation mode used by the electronic device can be specified by the user (ie, the near-end user), and can also be set by the electronic device by default (for example, the second echo cancellation mode is used by default).

For example, referring to FIG. 5, the electronic device provides an echo cancellation mode configuration interface. The echo cancellation mode configuration interface includes a prompt message “please move the slider to select the echo cancellation mode to be adopted” and a prompt message “the slider will not be centered. "Echo cancellation", in addition, the echo cancellation mode configuration interface also includes an operable control, the operable control includes a circular slider for the user to select the echo cancellation mode, wherein the circular slider includes three states, which are instructions The centered state where echo cancellation is not performed, the left state indicating the adoption of the first echo cancellation mode, and the right state indicating the adoption of the second echo cancellation mode.

In 204, the electronic device performs echo estimation according to its echo path delay and the far-end audio signal to obtain a first echo signal.

It should be noted that in this embodiment, the transmission duration of the echo from the speaker to the microphone is recorded as the echo path delay. The echo path delay is obtained before 201 according to the preset frequency sweep signal and the delayed frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal, and the delay estimation method provided by the embodiment of the present application is used to estimate the delay.

When it is determined that the first echo cancellation mode is used for echo cancellation, the electronic device will first perform echo estimation based on the echo path delay and the far-end audio signal, and record the estimated echo signal at this time as the first echo signal.

Optionally, in an embodiment, when the electronic device performs echo estimation based on the echo path delay and the far-end audio signal to obtain the first echo signal, it may perform:

The electronic device delays the far-end audio signal according to the delay of its echo path, and uses the delayed far-end audio signal as the first echo signal.

For example, if the delay of the echo path is 50 milliseconds, the far-end audio signal is delayed by 50 milliseconds in the time domain, and the far-end audio signal delayed by 50 milliseconds is used as the first echo signal.

Optionally, in an embodiment, before using the delayed far-end audio signal as the first echo signal, the electronic device may perform:

The electronic device performs gain control on the delayed far-end audio signal according to the preset gain coefficient.

Wherein, the preset gain coefficient may be an empirical value, which is used to perform gain control on the delayed far-end audio signal, thereby reducing the amplitude of the far-end audio signal, so that the estimated first echo signal can more closely approximate the real echo.

In 205, the electronic device subtracts the first echo signal from the near-end audio signal to obtain a first residual audio signal.

In this embodiment, after estimating the first echo signal, the electronic device may subtract the first echo signal from the near-end audio signal to eliminate the echo in the first audio signal, and reduce the near-end audio signal at this time The residual audio signal obtained by removing the first echo signal is recorded as the first residual audio signal.

In 206, the electronic device updates the adaptive filter according to its echo path delay.

In 207, the electronic device performs echo estimation according to the updated adaptive filter and the far-end audio signal to obtain a second echo signal;

In 208, the electronic device subtracts the second echo signal from the near-end audio signal to obtain a second residual audio signal.

In this embodiment, an adaptive filter technique may be used to simulate the echo path, so that the echo signal is estimated based on the far-end audio signal. Among them, the echo path is also the propagation path of the echo from the speaker to the microphone.

When it is determined to use the second echo cancellation mode for echo cancellation, the electronic device will first update the adaptive filter according to its echo path delay, that is, update the filter coefficient of the adaptive filter.

Optionally, in an embodiment, when the electronic device updates the adaptive filter according to its echo path delay, it may perform:

The electronic device delays the far-end audio signal according to the delay of its echo path, and updates the adaptive filter according to the near-end audio signal and the delayed far-end audio signal.

The above update operation of the adaptive filter can be expressed as:

h (n) = h (n-1) + alpha * e (n-1) * x (n) / (x (n) ² + beta);

e (n-1) = y (n) -x (n) * h (n-1);

Among them, h (n) represents the updated filter coefficient, h (n-1) represents the filter coefficient before updating, alpha represents the update step size (takes the empirical value), and x (n) represents the delayed far-end audio Signal, beta represents the regularization factor (takes empirical value), e (n-1) represents the residual audio signal obtained by performing echo cancellation before the update of the filter coefficients, and y (n) represents the near-end audio signal.

After completing the update of the adaptive filter, the electronic device performs echo estimation according to the updated adaptive filter and the far-end audio signal, and records the estimated echo signal at this time as the second echo signal.

The above echo estimation based on the updated adaptive filter and the far-end audio signal can be expressed as:

z (n) = x (n) * h (n);

Where z (n) represents the estimated second echo signal.

After the electronic device performs echo estimation according to the updated adaptive filter and the far-end audio signal, and obtains the second echo signal, the second echo signal can be subtracted from the near-end audio signal to eliminate the near-end audio signal Echo, and the residual audio signal obtained by subtracting the second echo signal from the near-end audio signal at this time is recorded as the second residual audio signal.

The above subtracting the second echo signal from the near-end audio signal can be expressed as:

e (n) = y (n) -z (n);

Where e (n) represents the second residual audio signal.

Optionally, in an embodiment, before determining the current echo cancellation mode, the electronic device may also execute:

The electronic device recognizes whether the far-end audio signal is a voice signal;

If yes, the electronic device determines the current echo cancellation mode.

In this embodiment, first recognize whether the far-end audio signal is a voice signal, and if the far-end audio signal is recognized as a voice signal, the electronic device further determines the current echo cancellation mode, so as to determine the near-end audio signal according to the current echo cancellation mode For echo cancellation, please refer to the relevant description in the above embodiment for details, and will not repeat them here; if it is recognized that the far-end audio signal is not a voice signal, the electronic device determines that there is no need to perform echo cancellation on the near-end audio signal, and directly The audio signal at the end is transmitted to the remote device.

As an optional implementation, when identifying whether the far-end audio signal is a voice signal, the electronic device may perform:

The electronic device obtains the energy value of the remote audio signal;

The electronic device determines whether the energy value of the far-end audio signal reaches the preset energy value, and then determines that the far-end audio signal is a voice signal, otherwise it is not a voice signal.

Wherein, the preset energy value can be obtained by a person of ordinary skill in the art according to actual needs.

As another optional implementation manner, when identifying whether the far-end audio signal is a voice signal, the electronic device may perform:

The electronic device obtains the autocorrelation value of the far-end audio signal;

The electronic device determines whether the auto-correlation value of the far-end audio signal reaches a preset threshold, and then determines that the far-end audio signal is a voice signal, otherwise it is not a voice signal.

Wherein, the preset threshold can be obtained by a person of ordinary skill in the art according to actual needs.

As yet another optional implementation manner, when identifying whether the far-end audio signal is a voice signal, the electronic device may perform:

The electronic device obtains the energy value of the remote audio signal;

The electronic device determines whether the energy value of the remote audio signal reaches the preset energy value;

If yes, the electronic device obtains the autocorrelation value of the remote audio signal;

Optionally, in an embodiment, after subtracting the first echo signal from the near-end audio signal to obtain the first residual audio signal, the electronic device may further execute:

The electronic device transmits the first residual audio signal to the remote device.

The first residual signal is the near-end audio signal after echo cancellation according to the first echo cancellation mode. When the far-end device plays the first residual signal through its own speaker, the far-end user will hear the near-end user's speech And will not hear your own echo.

Optionally, in an embodiment, after subtracting the second echo signal from the near-end audio signal to obtain the second residual audio signal, the electronic device may further execute:

The electronic device transmits the second residual audio signal to the remote device.

The second residual signal is the near-end audio signal after echo cancellation according to the second echo cancellation mode. When the far-end device plays the second residual signal through its own speaker, the far-end user will hear the near-end user's speech And will not hear your own echo.

Please refer to FIG. 6, which is a schematic flowchart of a delay estimation method according to an embodiment of the present application. The delay estimation method can be applied to electronic devices. The flow of the delay estimation method may include:

In 301, an electronic device provides a preset frequency sweep signal to a speaker to play sound through the speaker.

It should be noted that the speaker may be an independent speaker externally connected to the electronic device, or may be a built-in speaker of the electronic device.

Among them, the preset frequency sweep signal may be generated in real time, or may be stored locally in the electronic device in advance.

If s (t) is used to represent the preset frequency sweep signal, the preset frequency sweep signal can be expressed as:

Where A ₁ represents the amplitude of the preset frequency sweep signal, T represents the duration of the preset frequency sweep signal, f ₂ represents the end frequency of the preset frequency sweep signal, f ₁ represents the start frequency of the preset frequency sweep signal, t Represents the variable "time".

It should be noted that the specific parameter configuration of the preset frequency sweep signal can be configured by a person of ordinary skill in the art according to experience.

In this embodiment, the electronic device first provides a preset frequency sweep signal to the speaker, and plays the sound of the preset frequency sweep signal through the speaker.

In 302, the electronic device collects sound through a microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal.

In this embodiment, during the process of providing the preset frequency sweep signal to the speaker, the electronic device collects sound through the microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal. Wherein, the delayed frequency sweep signal is also the preset frequency sweep signal after the delay of the delayed echo path.

If r (t) is used to represent the delayed sweep signal and Δt is used to represent the echo path delay, then the delayed sweep signal can be expressed as:

Among them, A ₂ represents the amplitude of the delayed sweep signal.

In 303, the electronic device estimates the overlapping portion of the preset frequency sweep signal and the delayed frequency sweep signal, and multiplies the overlapping portion of the preset frequency sweep signal and the delayed frequency sweep signal to obtain an operation result.

In this embodiment, after acquiring the delayed sweep signal corresponding to the preset sweep signal, the electronic device further estimates the overlapping portion of the preset sweep signal and the delayed sweep signal, which can be estimated based on experience, and The correlation between the preset frequency sweep signal and the delayed frequency sweep signal can be calculated, so that the overlapping portion of the preset frequency sweep signal and the delayed frequency sweep signal can be estimated according to the calculated correlation.

After estimating the overlapping part of the preset frequency sweep signal and the delayed sweep frequency signal, the electronic device multiplies the overlapping part of the preset frequency sweep signal and the delayed sweep frequency signal to obtain the operation result, which can be expressed as:

It can be seen from the calculation results obtained that there is a fixed frequency component with the echo path delay Δt as a variable.

In 304, the electronic device transforms the obtained operation result from the time domain to the frequency domain, and determines the frequency at the maximum amplitude of the operation result.

In 305, the electronic device estimates the echo path delay of the electronic device according to the foregoing frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.

The electronic device multiplies the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal to obtain the operation result, and then further transforms the obtained operation result from the time domain to the frequency domain to determine the maximum amplitude in the operation result Frequency.

After that, the electronic device can estimate the echo path delay of the electronic device according to the foregoing frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal according to the following formula:

△ T = f _d * T / (f ₂ -f ₁ );

Where f _d represents the frequency at the maximum amplitude in the calculation result.

In an embodiment, the obtained operation result is transformed from the time domain to the frequency domain, and the electronic device may perform:

Electronic equipment uses fast Fourier transform to transform the obtained operation results from time domain to frequency domain.

In an embodiment, before providing a preset frequency sweep signal to the speaker to play a sound through the speaker, the electronic device may also perform:

The electronic device collects sound through the microphone to obtain the environmental audio signal;

The electronic device determines whether the current environment is in a quiet state according to the environmental audio signal;

If yes, the preset frequency sweep signal is provided to the speaker to play sound through the speaker.

There is no specific limitation on the duration of the environmental audio signal collected by the electronic device, which can be set by a person of ordinary skill in the art according to actual needs. For example, the electronic device can be set to collect the environmental audio signal for 5 seconds.

After collecting the environmental audio signal, the electronic device determines whether the current environment is in a quiet state based on the environmental audio signal, wherein the electronic device can determine whether the energy value of the environmental audio signal continues for a preset duration less than the preset energy value (can It is configured as the same preset energy value used to determine whether the far-end audio signal is a voice signal in the above embodiment), if it is, it is determined that the environment it is currently in is in a quiet state, otherwise it is not in a quiet pass. It should be noted that, for the value of the preset duration, a person of ordinary skill in the art can take an experience value, for example, it can be configured to 5 seconds.

When it is determined that the current environment is in a quiet state, the electronic device can provide a preset frequency sweep signal to the speaker to play sound through the speaker.

Optionally, in an embodiment, after determining whether the environment in which it is currently located is in a quiet state according to the ambient audio signal, the electronic device may also execute:

If not, continue to judge whether the current environment is in a quiet state, until the current environment is in a quiet state, go to execute "provide a preset sweep signal to the speaker to play sound through the speaker".

In an embodiment, when multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, the electronic device may perform:

The electronic device selects a part of a preset length from the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal for multiplication.

Among them, in order to reduce the time required for the multiplication operation, a part of a preset length can be selected from the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal for multiplication operation, wherein, for the value of the preset length, An empirical value can be taken by a person of ordinary skill in the art, for example, one audio frame or multiple audio frames can be taken.

At this time, the electronic device multiplies a part of the predetermined length from the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, which can be expressed as:

Among them, n = [1, N], N represents the preset length.

Please refer to FIG. 7, which is a schematic structural diagram of an echo cancellation device according to an embodiment of the present application. The echo cancellation device can be applied to electronic equipment. The echo cancellation apparatus may include: a first acquisition module 401, a second acquisition module 402, an echo estimation module 403, and an echo cancellation module 404.

The first obtaining module 401 is used to obtain remote audio signals from the remote device;

The second obtaining module 402 is configured to obtain a near-end audio signal corresponding to the far-end audio signal through a microphone;

The echo estimation module 403 is configured to perform echo estimation according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal;

The echo cancellation module 404 is used to subtract the first echo signal from the near-end audio signal to obtain a first residual audio signal;

The delay of the echo path is estimated according to the preset frequency sweep signal and the delayed frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal.

In an embodiment, before performing echo estimation based on the echo path delay of the electronic device and the far-end audio signal, the echo estimation module 403 may be used to:

Determine the current echo cancellation mode, where the echo cancellation mode includes the first echo cancellation mode or the second echo cancellation mode;

If the current echo cancellation mode is the first echo cancellation mode, the echo estimation is performed according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal.

In one embodiment, before determining the current echo cancellation mode, the echo estimation module 403 may also be used to:

Identify whether the far-end audio signal is a voice signal;

If so, determine the current echo cancellation mode.

In an embodiment, when identifying whether the far-end audio signal is a voice signal, the echo estimation module 403 may be used to:

Obtain the autocorrelation value of the far-end audio signal;

It is determined whether the auto-correlation value of the far-end audio signal reaches a preset threshold, and it is determined that the far-end audio signal is a voice signal, otherwise it is not a voice signal.

Obtain the energy value of the far-end audio signal;

To determine whether the energy value of the far-end audio signal reaches the preset energy value, it is determined that the far-end audio signal is a voice signal, otherwise it is not a voice signal.

In an embodiment, when performing echo estimation based on the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal, the echo estimation module 403 may be used to:

Delay the far-end audio signal according to the delay of the echo path of the electronic device, and use the delayed far-end audio signal as the first echo signal.

In an embodiment, the echo cancellation device further includes a transmission module for transmitting the first residual audio signal to the first residual audio signal after the echo cancellation module 404 subtracts the first echo signal from the near-end audio signal to Remote device.

In one embodiment, after determining the current echo cancellation mode, the echo estimation module 403 may also be used to:

If the current echo cancellation mode is the second echo cancellation mode, the adaptive filter is updated according to the echo path delay of the electronic device;

Echo estimation based on the updated adaptive filter and the far-end audio signal to obtain a second echo signal;

The echo cancellation module 404 can also be used to subtract the second echo signal from the near-end audio signal to obtain a second residual audio signal.

In an embodiment, after the echo cancellation module 404 subtracts the second echo signal from the near-end audio signal to obtain the second residual audio signal, the transmission module may also be used to:

Transmit the second residual audio signal to the remote device.

Please refer to FIG. 8, which is a schematic structural diagram of a delay estimation apparatus according to an embodiment of the present application. The delay estimation device can be applied to an electronic device delay estimation device 500 and can include a signal playback module 501, a signal acquisition module 502, a multiplication module 503, a frequency determination module 504, and a delay estimation module 505.

The signal playing module 501 is used to provide a preset frequency sweep signal to the speaker to play sound through the speaker;

The signal collection module 502 is used to collect sound through a microphone to obtain a delayed sweep signal corresponding to a preset sweep signal;

The multiplication operation module 503 is used to estimate the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiply the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal to obtain an operation result;

The frequency determination module 504 is used to transform the obtained operation result from the time domain to the frequency domain, and determine the frequency at the maximum amplitude of the operation result;

The delay estimation module 505 is used to estimate the echo path delay of the electronic device according to the aforementioned frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.

In an embodiment, when transforming the obtained operation result from the time domain to the frequency domain, the frequency determination module 504 may be used to:

The fast Fourier transform is used to transform the obtained operation result from time domain to frequency domain.

In an embodiment, before providing a preset frequency sweep signal to the speaker to play a sound through the speaker, the signal collection module 502 is further used to collect sound through a microphone to obtain an ambient audio signal;

Determine whether the current environment of the electronic device is in a quiet state according to the obtained environmental audio signal;

If yes, the signal playback module 501 provides a preset frequency sweep signal to the speaker to play sound through the speaker.

In an embodiment, when multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, the multiplication operation module 503 may be used to:

Select the part of the preset length from the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal for multiplication.

An embodiment of the present application provides a computer-readable storage medium on which a computer program is stored, and when the stored computer program is executed on a computer, causes the computer to perform the steps in the echo cancellation method provided in this embodiment, or The computer is caused to perform the steps in the delay estimation method as provided in this embodiment.

An embodiment of the present application also provides an electronic device, including a memory, a processor, and the processor executes the steps in the echo cancellation method provided in this embodiment by calling a computer program stored in the memory, or executes the extension as provided in this embodiment Steps in the estimation method.

Please refer to FIG. 9, which is a schematic structural diagram of an electronic device according to an embodiment of the present application. The electronic device may include a speaker 601, a memory 602, a processor 603, a microphone 604, and other components. A person of ordinary skill in the art may understand that the structure of the electronic device shown in FIG. 9 does not constitute a limitation on the electronic device, and may include more or fewer components than those illustrated, or combine certain components, or arrange different components .

The speaker 601 may output an audio signal to play sound.

The memory 602 may be used to store application programs and data. The application program stored in the memory 602 contains executable code. The application program can form various functional modules. The processor 603 executes application programs stored in the memory 602 to execute various functional applications and data processing.

The processor 603 is the control center of the electronic device, and uses various interfaces and lines to connect the various parts of the entire electronic device. Various functions and processing data, so as to carry out overall monitoring of electronic equipment.

The microphone 604 can collect sounds and generate audio signals.

In an embodiment, the processor 603 in the electronic device loads the executable code corresponding to the process of one or more echo cancellation programs into the memory 602 according to the following instructions, and the processor 603 executes and stores the The application program in the memory 602, thereby executing:

Obtain the far-end audio signal from the remote device;

Obtain the near-end audio signal corresponding to the far-end audio signal through the microphone;

Echo estimation based on the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal;

Alternatively, the processor 603 in the electronic device will load the executable code corresponding to the process of one or more delay estimation programs into the memory 602 according to the following instructions, and the processor 603 runs and stores the memory in the memory 602 Application to execute:

Provide a preset frequency sweep signal to the speaker to play sound through the speaker;

Collect sound through the microphone to obtain the delayed sweep signal corresponding to the preset sweep signal;

Estimate the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiply the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal to obtain the operation result;

Transform the obtained operation result from the time domain to the frequency domain to determine the frequency at the maximum amplitude of the operation result;

The echo path delay of the electronic device is estimated according to the aforementioned frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.

Please refer to FIG. 10, which is another schematic structural diagram of an electronic device provided by an embodiment of the present application. The difference from the electronic device shown in FIG. 6 is that the electronic device further includes components such as an input unit 605 and an output unit 606.

The input unit 605 can be used to receive input numbers, character information, or user characteristic information (such as fingerprints), and generate keyboard, mouse, joystick, optical, or trackball signal inputs related to user settings and function control.

The output unit 606 may be used to display information input by the user or information provided to the user, such as a screen.

In the embodiment of the present application, the processor 603 in the electronic device loads the executable code corresponding to the process of one or more echo cancellation programs into the memory 602 according to the following instructions, and the processor 603 executes and stores The application program in the memory 602, thereby executing:

Obtain the far-end audio signal from the remote device;

In an embodiment, before performing the echo estimation based on the echo path delay of the electronic device and the far-end audio signal, the processor 603 may execute:

In one embodiment, before determining the current echo cancellation mode, the processor 603 may execute:

Identify whether the far-end audio signal is a voice signal;

If so, determine the current echo cancellation mode.

In an embodiment, when identifying whether the far-end audio signal is a voice signal, the processor 603 may execute:

Obtain the autocorrelation value of the far-end audio signal;

Obtain the energy value of the far-end audio signal;

In an embodiment, when performing echo estimation based on the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal, the processor 603 may execute:

In an embodiment, after subtracting the first echo signal from the near-end audio signal to obtain the first residual audio signal, the processor 603 may execute:

Transmit the first residual audio signal to the remote device.

In one embodiment, after determining the current echo cancellation mode, the processor 603 may execute:

The second echo signal is subtracted from the near-end audio signal to obtain a second residual audio signal.

In an embodiment, after subtracting the second echo signal from the near-end audio signal to obtain the second residual audio signal, the processor 603 may execute:

Transmit the second residual audio signal to the remote device.

In an embodiment, when transforming the obtained operation result from the time domain to the frequency domain, the processor 603 may execute:

In one embodiment, before providing a preset frequency sweep signal to the speaker to play sound through the speaker, the processor 603 may execute:

Collect sound through microphone to get environmental audio signal;

In an embodiment, when multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, the processor 603 may execute:

In the above embodiments, the description of each embodiment has its own emphasis. For a part that is not detailed in an embodiment, you can refer to the above detailed description for the echo cancellation method / delay estimation method, which will not be repeated here. .

The echo cancellation device provided by the embodiment of the present application and the echo cancellation method in the above embodiments belong to the same concept. Any method provided in the echo cancellation method embodiment can be run on the echo cancellation device, and the specific implementation process is described in echo cancellation The method embodiments are not repeated here.

The delay estimation device provided by the embodiment of the present application and the delay estimation method in the above embodiment belong to the same concept. Any method provided in the delay estimation method embodiment can be run on the delay estimation device, and the specific implementation process For details, refer to the embodiment of the delay estimation method, and details are not described herein again.

It should be noted that, for the echo cancellation method / delay estimation method in the embodiment of the present application, a person of ordinary skill in the art can understand that all or part of the process for implementing the echo cancellation method / delay estimation method in the embodiment of the present application can be obtained through Program to control the related hardware to complete, the computer program can be stored in a computer readable storage medium, such as stored in memory, and executed by at least one processor, during the implementation process can include, for example, echo cancellation method / delay The flow of the embodiment of the estimation method. Among them, the storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM, Read Only Memory), a random access memory (RAM, Random Access Memory), etc.

For the echo cancellation device / delay estimation in the embodiment of the present application, each functional module may be integrated into one processing chip, or each module may exist alone physically, or two or more modules may be integrated into one Module. The above integrated modules may be implemented in the form of hardware or software function modules. If the integrated module is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium, such as a read-only memory, magnetic disk, or optical disk.

The above describes an echo cancellation method, delay estimation method, device, storage medium, and electronic equipment provided by the embodiments of the present application in detail. Specific examples are used to explain the principles and implementations of the present invention. The description of the embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation mode and application scope. The content of this specification should not be construed as a limitation of the present invention.

Claims

An echo cancellation method applied to electronic equipment, including:

Obtain the far-end audio signal from the remote device;

Acquiring a near-end audio signal corresponding to the far-end audio signal through a microphone;

Performing echo estimation according to the echo path delay of the electronic device and the far-end audio signal to obtain a first echo signal;

Subtracting the first echo signal from the near-end audio signal to obtain a first residual audio signal;

Wherein, the delay of the echo path is estimated according to a preset frequency sweep signal and a delayed frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal.
The echo cancellation method according to claim 1, wherein the performing echo estimation according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal further comprises:

Determine the current echo cancellation mode, where the echo cancellation mode includes a first echo cancellation mode or a second echo cancellation mode, and the processing speed of the first echo cancellation mode is faster than the processing speed of the second echo cancellation mode ;

If the current echo cancellation mode is the first echo cancellation mode, echo estimation is performed according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal.
The echo cancellation method according to claim 2, wherein before determining the current echo cancellation mode, the method further comprises:

Identify whether the far-end audio signal is a voice signal;

If so, determine the current echo cancellation mode.
The echo cancellation method according to claim 3, wherein the identifying whether the far-end audio signal is a voice signal includes:

Acquiring the autocorrelation value of the far-end audio signal;

To determine whether the auto-correlation value reaches a preset threshold, it is determined that the far-end audio signal is a voice signal, otherwise it is not a voice signal.
The echo cancellation method according to claim 1, wherein the performing echo estimation according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal includes:

Delay the far-end audio signal according to the delay of the echo path, and use the delayed far-end audio signal as the first echo signal.
The echo cancellation method according to claim 1, wherein after subtracting the first echo signal from the near-end audio signal to obtain a first residual audio signal, further comprising:

Transmitting the first residual audio signal to the remote device.
The echo cancellation method according to claim 2, wherein after determining the current echo cancellation mode, the method further comprises:

If the current echo cancellation mode is the second echo cancellation mode, update the adaptive filter according to the echo path delay;

Performing echo estimation according to the updated adaptive filter and the far-end audio signal to obtain a second echo signal;

The second echo signal is subtracted from the near-end audio signal to obtain a second residual audio signal.
The echo cancellation method according to claim 7, wherein after subtracting the second echo signal from the near-end audio signal to obtain a second residual audio signal, further comprising:

Transmitting the second residual audio signal to the remote device.
A delay estimation method applied to electronic equipment, including:

Providing a preset frequency sweep signal to the speaker to play sound through the speaker;

Collecting sound through a microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal;

Estimating the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal to obtain an operation result;

Transforming the operation result from the time domain to the frequency domain, and determining the frequency at the maximum amplitude of the operation result;

The echo path delay of the electronic device is estimated according to the frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.
The delay estimation method according to claim 9, wherein the transforming the operation result from the time domain to the frequency domain includes:

The fast Fourier transform is used to transform the operation result from the time domain to the frequency domain.
The method for delay estimation according to claim 9, wherein before providing a preset frequency sweep signal to the speaker to play a sound through the speaker, further comprising:

Collect sound through microphone to get environmental audio signal;

Determine whether the environment in which the electronic device is currently in a quiet state according to the environmental audio signal;

If yes, the preset frequency sweep signal is provided to the speaker to play sound through the speaker.
The delay estimation method according to claim 9, wherein the multiplying the overlapping part of the preset frequency sweep signal and the delay frequency sweep signal includes:

A part of a preset length is selected from the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal for multiplication.
An echo cancellation device applied to electronic equipment, including:

The first obtaining module is used to obtain remote audio signals from the remote device;

A second obtaining module, configured to obtain a near-end audio signal corresponding to the far-end audio signal through a microphone;

An echo estimation module, configured to perform echo estimation based on the echo path delay of the electronic device and the far-end audio signal to obtain a first echo signal;

An echo cancellation module, configured to subtract the first echo signal from the near-end audio signal to obtain a first residual audio signal;

Wherein, the delay of the echo path is estimated according to a preset frequency sweep signal and a delayed frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal.
A delay estimation device applied to electronic equipment, including:

The signal playing module is used to provide a preset frequency sweep signal to the speaker to play sound through the speaker;

A signal collection module for collecting sound through a microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal;

A multiplication module, used to estimate the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiply the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, Get the operation result;

A frequency determination module, configured to transform the operation result from the time domain to the frequency domain, and determine the frequency at the maximum amplitude of the operation result;

The delay estimation module is used to estimate the echo path delay of the electronic device according to the frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.
A storage medium on which a computer program is stored, wherein when the computer program is executed on a computer, the computer is caused to perform the method according to any one of claims 1 to 8, or the computer is caused to The method according to any one of claims 9 to 12 is performed.
An electronic device includes a memory and a processor, wherein the processor is used to execute a computer program stored in the memory by executing:

Obtain the far-end audio signal from the remote device;

Acquiring a near-end audio signal corresponding to the far-end audio signal through a microphone;

Performing echo estimation according to the echo path delay of the electronic device and the far-end audio signal to obtain a first echo signal;

Subtracting the first echo signal from the near-end audio signal to obtain a first residual audio signal;

Wherein, the delay of the echo path is estimated according to a preset frequency sweep signal and a delayed frequency sweep signal collected by the microphone corresponding to the preset frequency sweep signal.
The electronic device according to claim 16, wherein before performing echo estimation based on the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal, the processor is configured to execute:

Determine the current echo cancellation mode, where the echo cancellation mode includes a first echo cancellation mode or a second echo cancellation mode, and the processing speed of the first echo cancellation mode is faster than the processing speed of the second echo cancellation mode ;

If the current echo cancellation mode is the first echo cancellation mode, echo estimation is performed according to the echo path delay of the electronic device and the far-end audio signal to obtain the first echo signal.
The electronic device of claim 17, wherein after determining the current echo cancellation mode, the processor is configured to execute:

If the current echo cancellation mode is the second echo cancellation mode, update the adaptive filter according to the echo path delay;

Performing echo estimation according to the updated adaptive filter and the far-end audio signal to obtain a second echo signal;

The second echo signal is subtracted from the near-end audio signal to obtain a second residual audio signal.
An electronic device includes a memory and a processor, wherein the processor is used to execute a computer program stored in the memory by executing:

Providing a preset frequency sweep signal to the speaker to play sound through the speaker;

Collecting sound through a microphone to obtain a delayed frequency sweep signal corresponding to the preset frequency sweep signal;

Estimating the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, and multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal to obtain an operation result;

Transforming the operation result from the time domain to the frequency domain, and determining the frequency at the maximum amplitude of the operation result;

The echo path delay of the electronic device is estimated according to the frequency and the duration, end frequency, and start frequency of the preset frequency sweep signal.
The electronic device according to claim 19, wherein, when multiplying the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal, the processor is configured to execute:

A part of a preset length is selected from the overlapping part of the preset frequency sweep signal and the delayed frequency sweep signal for multiplication.