Audio reverberation method and apparatus, electronic device, medium, product, and vehicle

Abstract

The application discloses an audio reverberation method and device, electronic equipment, medium, product and vehicle. The method comprises the following steps: determining a target reverberation time of the audio to be reverberated according to the attenuation speed of the environmental sound feature of the target audio reverberation scene in each frequency band of the audio to be reverberated; determining the delay parameter of each delay line in the feedback delay network according to the target reverberation time; updating the coefficient of the state variable filter on each delay line according to the target reverberation time and the delay parameter of each delay line, and obtaining an updated state variable filter; performing attenuation processing on the delayed audio through the updated state variable filter, and obtaining the output audio of each delay line; and performing superposition processing on the output audio output by the multiple delay lines and the audio to be reverberated, and obtaining the target audio. The scheme can improve the stability of the audio reverberation system.

Description

Technical Field

[0001] This application belongs to the field of audio signal processing, and particularly relates to an audio reverberation method, apparatus, electronic equipment, medium, product, and vehicle. Background Technology

[0002] In related technologies, feedback delay networks are commonly used to implement audio reverberation. The filters in a feedback delay network are typically implemented using a single second-order filter cascaded together. However, in time-varying systems, this approach causes audio numerical overflow during the audio reverberation process, reducing the stability of the audio reverberation system. Summary of the Invention

[0003] This application provides an audio reverberation method, apparatus, electronic device, medium, product, and vehicle that can improve the stability of the audio reverberation system.

[0004] In a first aspect, embodiments of this application provide an audio reverberation method, the method comprising: determining a target reverberation time corresponding to the audio to be reverberated based on the attenuation rate of the ambient sound features corresponding to the target audio reverberation scene at each frequency band in the audio to be reverberated; determining delay parameters of each delay line in a feedback delay network based on the target reverberation time, wherein the feedback delay network includes at least multiple delay lines, each delay line being equipped with a delay unit and a state variable filter; updating the coefficients of the state variable filter on each delay line based on the target reverberation time and the delay parameters corresponding to each delay line, thereby obtaining an updated state variable filter; performing attenuation processing on the corresponding delayed audio through the updated state variable filter to obtain the output audio corresponding to each delay line, wherein the delayed audio is the audio obtained after delay processing of the audio to be reverberated by the delay unit on the corresponding delay line; and superimposing the output audio output from the multiple delay lines in the feedback delay network and the audio to be reverberated to obtain a target audio corresponding to the target audio reverberation scene.

[0005] Secondly, embodiments of this application provide an audio reverberation device, comprising: a reverberation time determination module, configured to determine a target reverberation time corresponding to the audio to be reverberated based on the attenuation rate of the ambient sound characteristics corresponding to the target audio reverberation scene at each frequency band in the audio to be reverberated; a parameter calculation module, configured to determine the delay parameters of each delay line in the feedback delay network based on the target reverberation time, wherein the feedback delay network includes at least multiple delay lines, each delay line being equipped with a delay unit and a state variable filter; a coefficient update module, configured to update the coefficients of the state variable filter on each delay line based on the target reverberation time and the delay parameters corresponding to each delay line, thereby obtaining an updated state variable filter; an attenuation module, configured to attenuate the corresponding delayed audio through the updated state variable filter, thereby obtaining the output audio corresponding to each delay line, wherein the delayed audio is the audio obtained after delaying the audio to be reverberated through the delay unit on the corresponding delay line; and a reverberation module, configured to superimpose the output audio output from the multiple delay lines in the feedback delay network and the audio to be reverberated, thereby obtaining a target audio corresponding to the target audio reverberation scene.

[0006] Thirdly, embodiments of this application provide an electronic device, which includes: a processor and a memory storing computer program instructions; the processor executes the computer program instructions to implement the audio reverberation method as described in the first aspect.

[0007] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer program instructions that, when executed by a processor, implement the audio reverberation method as described in the first aspect.

[0008] Fifthly, embodiments of this application provide a computer program product in which instructions, when executed by a processor of an electronic device, cause the electronic device to perform the audio reverberation method as described in the first aspect.

[0009] In a sixth aspect, embodiments of this application provide a vehicle that includes at least one of the following: an audio reverberation device as described in the second aspect; an electronic device as described in the third aspect; and a computer-readable storage medium as described in the fourth aspect.

[0010] As can be seen from the above, in this embodiment of the application, a state variable filter is deployed in the feedback delay network to replace the single second-order filter in the related technology. Since the filters in the state variable filter achieve filtering efficiency by sharing state variables, the stability of the audio can be guaranteed, thereby improving the stability of the audio reverberation system.

[0011] Furthermore, compared with related technologies that only adjust the reverberation time of the feedback delay network and the delay parameters corresponding to each delay line, in the embodiment of this application, not only are the reverberation time and the delay parameters corresponding to each delay line adjusted during the audio reverberation process, but the coefficients of the state variable filter are also updated. This makes the state variable filter more adaptable to the current audio reverberation scenario, which not only improves the quality of audio reverberation but also enhances the stability of the audio reverberation system.

[0012] Therefore, it can be seen that the method proposed in the embodiments of this application can improve the stability of audio reverberation. Attached Figure Description

[0013] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] Figure 1 This is a network structure diagram of a feedback delay network provided in one embodiment of this application;

[0015] Figure 2 This is a flowchart illustrating an audio reverberation method provided in one embodiment of this application;

[0016] Figure 3 This is an overall flowchart of an audio reverberation method provided in one embodiment of this application;

[0017] Figure 4 This is a schematic diagram of the structure of an audio reverberation device provided in another embodiment of this application;

[0018] Figure 5 This is a schematic diagram of the structure of an electronic device provided in another embodiment of this application. Detailed Implementation

[0019] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0020] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0021] To facilitate understanding, before explaining the solution provided in this application, the background of the solution provided in this application will be explained first.

[0022] In related technologies, feedback delay networks are typically used in the reverberation process of audio. These networks usually incorporate filters to attenuate and filter the audio to be reverberated. These filters are often implemented by cascading multiple second-order bifilters. However, in time-varying systems, using multiple cascaded second-order bifilters to attenuate and filter audio can lead to numerical overflow in the resulting audio signal, and the audio reverberation system itself is unstable.

[0023] To address the problems of the prior art, embodiments of this application provide an audio reverberation method, apparatus, electronic device, medium, product, and vehicle. The audio reverberation method provided in this application embodiment is described below.

[0024] The audio reverberation method proposed in this application embodiment can be applied to feedback delay networks. Feedback delay networks can simulate the reverberation effect of audio through delay lines and feedback loops. By delaying and feeding back the input audio and mixing it with the input audio itself, the effect of sound reflection and echo in different spaces can be simulated.

[0025] In this embodiment, the feedback delay network includes multiple delay lines, each of which is equipped with a delay unit and a state variable filter.

[0026] As an example, Figure 1 The network structure diagram of the feedback delay network is shown. Figure 1 In the feedback delay network shown, four delay lines are deployed, each with a delay unit and a state variable filter. For example, in... Figure 1 In the middle, the delay units deployed on the four delay lines are z -M1z -M2 z -M3 z -M4 The state variable filters deployed on the four delay lines are SVF1, SVF2, SVF3, and SVF4, respectively. The feedback delay network also includes a feedback unit connecting the input and output of the multi-delay lines.

[0027] like Figure 1 As shown, the audio to be reverberated is input to each delay line in the feedback delay network, and each delay line has a fixed delay time and attenuation coefficient. For a certain delay line, after the input audio to be reverberated is processed by signal delay, it is attenuated by a state variable filter, and then mixed with the input audio by the feedback unit before being input to the delay line again. After delay and attenuation, the audio is mixed with the audio output from other delay lines and the original audio before being output to obtain the reverberated audio y(n).

[0028] It should be noted that in the above embodiments, the delay time and attenuation coefficient corresponding to each delay line can be set according to the actual desired reverberation effect. Additionally, Figure 1 The diagram only shows a feedback delay network with four delay lines. In practical applications, different numbers of delay lines can be set according to requirements. The more delay lines there are, the better the reverberation effect, but the computational load will also increase accordingly.

[0029] Furthermore, it should be noted that by adjusting the delay time and attenuation coefficient on different delay lines, different types of reverberation effects can be simulated, such as those found in concert halls and home theaters. Additionally, using a feedback delay network to achieve audio reverberation reduces computational complexity and results in high-quality reverberated audio.

[0030] The audio reverberation method proposed in the embodiments of this application will be described below.

[0031] Figure 2 A schematic flowchart of an audio reverberation method according to an embodiment of this application is shown. Figure 2 As shown, the method includes the following steps S201 to S205:

[0032] Step S201: Determine the target reverberation time of the audio to be reverberated based on the decay rate of the ambient sound characteristics corresponding to the target audio reverberation scene in each frequency band of the audio to be reverberated.

[0033] In step S201, the audio reverberation scene is the scene corresponding to the desired audio effect, such as a concert hall, theater, auditorium, etc. Different audio reverberation scenes have different impulse response files. The impulse response file includes the environmental sound characteristics of the corresponding audio reverberation scene. The environmental sound characteristics are used to characterize the signal reflection data and signal attenuation data of the impulse signal in the environment of the audio reverberation scene.

[0034] In addition, in step S201, the reverberation time (hereinafter referred to as RT60) is the time required for the sound energy to decay to 60 decibels of the original volume after the indoor sound source stops emitting sound. It is an important parameter for measuring the acoustic characteristics of a room and is used to describe the continuous reflection and attenuation of sound in the room.

[0035] It should be noted that, in this embodiment, when a user needs to add reverb to audio, they only need to determine the desired audio reverb effect or audio reverb scene. The audio reverb system can then select an impulse response file based on the user-determined audio reverb scene, and thus implement audio reverb based on the impulse response file. When a user needs to adjust the audio reverb scene, they only need to select the changed audio reverb scene, and the audio reverb system selects an impulse response file based on the changed audio reverb scene, without needing to change the feedback delay network.

[0036] Therefore, the audio reverberation method proposed in this application embodiment can realize audio reverberation in various audio reverberation scenarios. Compared with related technologies, where a feedback delay network can only realize audio reverberation in one audio reverberation scenario, the audio reverberation method proposed in this application embodiment can reduce the cost of audio reverberation.

[0037] Step S202: Determine the delay parameters of each delay line in the feedback delay network based on the target reverberation time.

[0038] In step S202, the feedback delay network includes at least multiple delay lines, each with a delay unit and a state variable filter deployed on it. The network structure of the feedback delay network has been described above and will not be repeated here.

[0039] Step S203: Based on the target reverberation time and the delay parameters corresponding to each delay line, update the coefficients of the state variable filter on each delay line to obtain the updated state variable filter.

[0040] In step S203, after determining the target reverberation time and the delay parameters corresponding to the delay unit, the amplitude response corresponding to the state variable filter can be determined. Then, the amplitude response of the state variable filter is inversely solved to obtain the coefficients of the state variable filter. The state variable filter at this time is the updated state variable filter.

[0041] It should be noted that in step S203, the state variable filters on different delay lines are independent of each other, that is, in this embodiment of the application, the coefficients of the state variable filters on different delay lines are adjusted separately.

[0042] As can be seen from step S203, in the embodiment of this application, in the process of implementing audio reverberation, not only the reverberation time and the delay parameters corresponding to each delay line are adjusted, but also the coefficients of the state variable filter are updated, so that the state variable filter can be more adapted to the current audio reverberation scenario, which can not only improve the quality of audio reverberation, but also improve the stability of the audio reverberation system.

[0043] Step S204: Attenuate the corresponding delayed audio using the updated state variable filter to obtain the output audio for each delay line.

[0044] In step S204, the delayed audio is the audio obtained after delaying the reverberant audio through the delay unit on the corresponding delay line.

[0045] For example, the audio reverberation system also acquires the first audio output from the first delay line fed back by the feedback unit, and superimposes the audio to be reverberated with the first audio to obtain a second audio; then, the second audio is delayed by the delay unit in the first delay line to obtain a delayed audio. Here, the first delay line is any one of multiple delay lines. For example, in... Figure 1 In this context, delayed audio can be the audio after delaying the reverberation audio; delayed audio can also be the audio obtained by superimposing the audio fed back by the feedback unit and the reverberation audio, and then delaying it again by the delay unit.

[0046] Furthermore, in step S204, the state variable filter is a digital filter that can process and synthesize audio signals. Specifically, the state variable filter can simultaneously provide the functions of a low-pass filter, a high-pass filter, and a band-pass filter. It allows for independent design of poles and amplitudes at different frequency bands, free synthesis of three filter outputs, and generation of arbitrary second-order transfer functions.

[0047] It should be noted that deploying state variable filters in the feedback delay network instead of a single two-order filter in related technologies can improve the stability of the audio reverberation system because the filters in the state variable filter achieve filtering efficiency by sharing state variables.

[0048] Step S205: The output audio of the multiple delay lines in the feedback delay network and the audio to be reverberated are superimposed to obtain the target audio corresponding to the target audio reverberation scene.

[0049] For example, in Figure 1 In this process, the audio output from each delay line is superimposed, and the superimposed audio is then superimposed with the audio to be reverberated to obtain the desired audio reverberation effect.

[0050] Based on the scheme defined in steps S201 to S205 above, it can be understood that in this embodiment, a state variable filter is deployed in the feedback delay network to replace the single second-order filter in related technologies. Since the filters in the state variable filter achieve filtering efficiency by sharing state variables, the stability of the audio can be guaranteed, thereby improving the stability of the audio reverberation system. In addition, compared with related technologies that only adjust the reverberation time of the feedback delay network and the delay parameters corresponding to each delay line, in this embodiment, in the process of implementing audio reverberation, not only the reverberation time and the delay parameters corresponding to each delay line are adjusted, but the coefficients of the state variable filter are also updated. This makes the state variable filter more adaptable to the current audio reverberation scenario, which not only improves the quality of audio reverberation but also improves the stability of the audio reverberation system.

[0051] Therefore, it can be seen that the method proposed in the embodiments of this application can improve the stability of audio reverberation.

[0052] The following describes the specific implementation of the method proposed in the embodiments of this application.

[0053] In this embodiment of the application, the audio reverberation system first determines the target reverberation time corresponding to the audio to be reverberated based on the decay rate of the ambient sound characteristics corresponding to the target audio reverberation scene in each frequency band of the audio to be reverberated, that is, performs step S201.

[0054] Specifically, the audio reverberation system obtains a target impulse response file that matches the target audio reverberation scene from multiple impulse response files. Then, it calculates the decay rate of the ambient sound features in the target impulse response file at multiple frequency bands. Based on the decay rate of the ambient sound features at multiple frequency bands, it determines the reverberation time corresponding to each frequency band. Finally, based on the frequency band corresponding to the audio to be reverberated, it determines the target reverberation time corresponding to the audio to be reverberated.

[0055] For example, there is a correlation between audio reverberation scenes and impulse response files. For instance, an audio reverberation scene has a scene identifier, and an impulse response file has a file identifier. The correlation between the scene identifier and the file identifier can be stored in a preset file. After determining the target audio reverberation scene, the target impulse response file can be determined by querying the aforementioned preset file. Then, the ambient sound characteristics corresponding to the target audio reverberation scene are obtained from the target impulse response file. The ambient sound characteristics at different frequency bands are statistically analyzed, and the decay rate corresponding to the ambient sound characteristics at each frequency band is determined, thereby determining the reverberation time corresponding to each frequency band. Finally, the target reverberation time of the audio to be reverberated can be determined based on the frequency band of the audio to be reverberated.

[0056] As an example, the audio to be reverberated may consist of sub-audio frequencies in multiple frequency bands. In this scenario, the audio reverberation system can divide the audio to be reverberated into multiple sub-audio frequencies and then determine the target reverberation time for each sub-audio frequency using the method described above.

[0057] The above method can accurately determine the target reverberation time corresponding to the audio to be reverberated, thereby making the audio reverberation effect more consistent with the target audio scene, improving the stability of audio reverberation, and thus meeting the user's expectations for audio reverberation.

[0058] Furthermore, after determining the target reverberation time, the delay parameters corresponding to each delay line can be determined based on the target reverberation time, and then the state variable filter can be updated according to the target reverberation time and the delay parameters.

[0059] Specifically, the audio reverberation system can determine the total delay parameters corresponding to the multiple delay lines based on the target reverberation time and the number of delay lines; and then determine the delay parameters corresponding to each delay line based on the total delay parameters.

[0060] For example, the total delay parameter and the target reverberation time can be expressed by the following formula:

[0061] M0≥λ*f s *RT 60

[0062] In the above formula, M0 is the total delay parameter; λ is a constant, which can be set according to actual needs, for example, λ can be set to 0.15; f s RT is the sampling rate; 60 The target reverberation time is denoted as M0. For example, when the sampling rate is 50 kHz and the target reverberation time is 1 s, the total delay parameter M0 ≥ 7500.

[0063] After determining the total delay parameters, the delay parameters corresponding to each delay line can be selected according to preset rules. The total delay parameters are the sum of the delay parameters corresponding to multiple delay lines, and the delay parameters corresponding to multiple delay lines are coprime. That is, the preset rules may include: the delay parameters corresponding to multiple delay lines are coprime.

[0064] It should be noted that the delay parameter is one of the important parameters of audio reverberation. After determining the target audio reverberation scene, the reasonable selection of reverberation time and delay parameters can not only make the reverberated audio more in line with the user's needs, but also improve the stability of the audio reverberation system.

[0065] Furthermore, after determining the target reverberation time and delay parameters, the audio reverberation system can update the coefficients of the state variable filter on each delay line according to the target reverberation time and the delay parameters corresponding to each delay line.

[0066] Specifically, the audio reverberation system determines the frequency response of the first state variable filter on the first delay line based on the target reverberation time and the delay parameters corresponding to the first delay line. Then, it calculates the amplitude response corresponding to the frequency response. Next, it performs inverse kinematics calculation on the amplitude response to obtain the target filter coefficients corresponding to the first state variable filter. Finally, it updates the initial filter coefficients of the first state variable filter to the target filter coefficients to obtain the updated state variable filter.

[0067] In the above embodiments, the first delay line is any one of the multiple delay lines, and the first state variable filter is a filter deployed on the first delay line.

[0068] It should be noted that, in the embodiments of this application, the amplitude response of the state variable filter is determined by the reverberation time and delay parameters, and the state variable filters on different delay lines are independent of each other.

[0069] In one embodiment, after obtaining the sampling rate of the first state variable filter, the attenuation response of the first state variable filter is determined based on the sampling rate and the target reverberation time, and then the product of the delay parameter corresponding to the first delay line and the attenuation response is determined as the frequency response of the first state variable filter.

[0070] For example, let M be the delay parameter on a certain delay line (i.e., the first delay line mentioned above) in the feedback delay network, and let A(z) be the time-domain representation of the transfer function of the state variable filter corresponding to this delay line, and let A(ω) be the frequency representation. Let B(ω) be the attenuation response (in decibels) of the audio to be reverberated as it passes through each delay line. Then B(ω) satisfies the following equation:

[0071]

[0072] In the above formula, RT 60 (ω) represents the target reverberation time; f s The sampling rate is the first state variable filter.

[0073] The frequency response A(ω) of the first state variable filter is expressed as:

[0074]

[0075] In the above formula, M is the delay parameter corresponding to the first delay line; RT 60 (ω) is the target reverberation time; A(ω) is the frequency response value of the first state variable filter; f s The sampling rate is the first state variable filter.

[0076] After determining the frequency response of the first state variable filter, the amplitude response of the first state variable filter can be obtained by calculating the amplitude of the frequency response of the first state variable filter.

[0077] In this embodiment, the state variable filter includes a low-pass filter, a high-pass filter, and a band-pass filter, and the low-pass filter, high-pass filter, and band-pass filter share state variables.

[0078] In one embodiment, the amplitude response is inversely solved to obtain the cutoff frequency, resonant parameters, and state values ​​of the first state variable filter. Based on the cutoff frequency, resonant parameters, and state values ​​of the first state variable filter, the transfer function of the bandpass filter is determined. Based on the cutoff frequency, state values ​​of the first state variable filter, and coefficients of the bandpass filter, the transfer function of the low-pass filter is determined. Based on the resonant parameters, coefficients of the low-pass filter, and coefficients of the bandpass filter, the transfer function of the high-pass filter is determined. Finally, the weighted values ​​of the target filter coefficients and the transfer functions of the bandpass filter, low-pass filter, and high-pass filter are calculated to obtain the updated transfer function of the state variable filter.

[0079] As can be seen from the above embodiments, the transfer function of the updated state variable filter is expressed by the following formula:

[0080] y(n)=c hp y hp (n)+c bp y bp (n)+c lp y lp (n)

[0081] In the above equation, y(n) is the output value of the transfer function of the updated state variable filter; c hp c represents the coefficients corresponding to the high-pass filter.bp c represents the coefficients corresponding to the bandpass filter. lp These are the coefficients corresponding to the low-pass filter; y hp (n) is the transfer function of the high-pass filter; y bp (n) is the transfer function of the bandpass filter; y lp (n) is the transfer function of the low-pass filter;

[0082]

[0083] y lp (n)=gy bp (n)+h2(n-1)

[0084] y hp (n)=x(n)-y lp (n)-2Ry bp (n)

[0085] h1(n)=2y bp (n)-h1(n-1)

[0086] h2(n)=2y lp (n)-h2(n-1)

[0087] Where g is the cutoff frequency of the updated state variable filter; R is the resonance parameter of the updated state variable filter; h1(n) and h2(n) are the first and second state values ​​corresponding to the updated state variable filter.

[0088] As can be seen from the above, in the process of implementing audio reverberation in this application embodiment, not only the reverberation time and the delay parameters corresponding to each delay line are adjusted, but the coefficients of the state variable filter are also updated, so that the state variable filter can be more adapted to the current audio reverberation scenario, which can not only improve the quality of audio reverberation, but also improve the stability of the audio reverberation system.

[0089] In one embodiment, Figure 3 This paper shows an overall flowchart of the audio reverberation method proposed in an embodiment of this application. Figure 3 It can be seen that this method mainly includes the following steps:

[0090] Step S301: Obtain the impulse response file corresponding to the target audio reverberation scene.

[0091] Step S302: Divide the audio to be reverberated into multiple frequency bands and determine the reverberation time of each frequency band.

[0092] Step S303: Determine the amplitude response of the state variable filter corresponding to each delay line based on the reverberation time and the delay parameter corresponding to each delay line in the feedback delay network.

[0093] Step S304: Perform inverse kinematics on the amplitude response to obtain the coefficients of the state variable filter.

[0094] In step S305, the coefficients of the state variable filter are updated to update the feedback delay network, and then the feedback delay network is used to reverberate the audio to be reverberated to obtain the target audio.

[0095] As described above, the audio reverberation method proposed in this application employs a state variable filter in the feedback delay network. This state variable filter typically consists of a low-pass filter, a band-pass filter, and a high-pass filter, which achieve their filtering effect by sharing state variables. Due to the shared state variables, the state variable filter ensures numerical stability. In time-varying systems, it is more stable than a single Biquad filter system when processing signals with high amplitude and high Q values, and it has simpler system stability conditions. Furthermore, because sharing state variables reduces redundant calculations, the calculation speed is faster, resulting in higher music quality.

[0096] Furthermore, in this embodiment, during the implementation of audio reverberation, not only are the reverberation time and the delay parameters corresponding to each delay line adjusted, but the coefficients of the state variable filter are also updated. This allows the state variable filter to better adapt to the current audio reverberation scenario, improving not only the quality of the audio reverberation but also the stability of the audio reverberation system. Moreover, users can change the desired reverberation effect in real time, ensuring the stability of the audio reverberation system.

[0097] This application also provides an audio reverberation device, such as... Figure 4 As shown, the device 400 includes: a reverberation time determination module 401, a parameter calculation module 402, a coefficient update module 403, an attenuation module 404, and a reverberation module 405.

[0098] The reverberation time determination module 401 is used to determine the target reverberation time of the audio to be reverberated based on the decay rate of the environmental sound characteristics corresponding to the target audio reverberation scene in each frequency band of the audio to be reverberated.

[0099] The parameter calculation module 402 is used to determine the delay parameters of each delay line in the feedback delay network based on the target reverberation time. The feedback delay network includes at least multiple delay lines, and each delay line is equipped with a delay unit and a state variable filter.

[0100] The coefficient update module 403 is used to update the coefficients of the state variable filter on each delay line according to the target reverberation time and the delay parameters corresponding to each delay line, so as to obtain the updated state variable filter.

[0101] The attenuation module 404 is used to attenuate the corresponding delayed audio through the updated state variable filter to obtain the output audio corresponding to each delay line. The delayed audio is the audio obtained after delaying the reverberation audio through the delay unit on the corresponding delay line.

[0102] The reverb module 405 is used to superimpose the output audio of the multiple delay lines in the feedback delay network and the audio to be reverberated to obtain the target audio corresponding to the target audio reverberation scene.

[0103] In one example, the reverberation time determination module is specifically used to obtain a target impulse response file that matches the target audio reverberation scene from multiple impulse response files. The impulse response file includes the ambient sound features of the corresponding audio reverberation scene. The ambient sound features are used to characterize the signal reflection data and signal attenuation data of the impulse signal in the environment of the audio reverberation scene. The module calculates the attenuation rate of the ambient sound features in the target impulse response file at multiple frequency bands. Based on the attenuation rate of the ambient sound features at multiple frequency bands, the module determines the reverberation time corresponding to each frequency band. Based on the frequency band corresponding to the audio to be reverberated, the module determines the target reverberation time corresponding to the audio to be reverberated.

[0104] In one example, the parameter calculation module is specifically used to determine the total delay parameter corresponding to the multiple delay lines based on the target reverberation time and the number of delay lines; and to determine the delay parameter corresponding to each delay line based on the total delay parameter, wherein the total delay parameter is the sum of the delay parameters corresponding to the multiple delay lines, and the delay parameters corresponding to the multiple delay lines are coprime.

[0105] In one example, the coefficient update module includes: a frequency response determination module, an amplitude response determination module, a coefficient determination module, and a target update module. The frequency response determination module determines the frequency response of a first state variable filter on the first delay line based on the target reverberation time and the delay parameters corresponding to the first delay line. The first delay line is any one of multiple delay lines, and the first state variable filter is a filter deployed on the first delay line. The amplitude response determination module calculates the amplitude response corresponding to the frequency response. The coefficient determination module performs inverse kinematics on the amplitude response to obtain the target filter coefficients corresponding to the first state variable filter. The target update module updates the initial filter coefficients of the first state variable filter to the target filter coefficients, resulting in the updated state variable filter.

[0106] In one example, the frequency response determination module is specifically used to obtain the sampling rate of the first state variable filter; determine the attenuation response of the first state variable filter based on the sampling rate and the target reverberation time; and determine the frequency response of the first state variable filter by multiplying the delay parameter corresponding to the first delay line with the attenuation response.

[0107] In one example, the state variable filter includes a low-pass filter, a high-pass filter, and a band-pass filter. The target update module is specifically used to perform inverse kinematics calculation on the amplitude response to obtain the cutoff frequency, resonance parameter, and state value of the first state variable filter. Based on the cutoff frequency, resonance parameter, and state value of the first state variable filter, the transfer function of the band-pass filter is determined. Based on the cutoff frequency, state value of the first state variable filter, and coefficients of the band-pass filter, the transfer function of the low-pass filter is determined. Based on the resonance parameter, coefficients of the low-pass filter, and coefficients of the band-pass filter, the transfer function of the high-pass filter is determined. The weighted values ​​of the target filter coefficients and the transfer functions of the band-pass filter, low-pass filter, and high-pass filter are calculated to obtain the updated transfer function of the state variable filter.

[0108] In one example, the feed-delay network further includes a feedback unit connected between the input and output of the multiple delay lines, and the audio reverberation device further includes: a delay processing module for acquiring the first audio output of the first delay line fed back by the feedback unit, wherein the first delay line is any one of the multiple delay lines; superimposing the audio to be reverberated with the first audio to obtain a second audio; and delaying the second audio through the delay unit in the first delay line to obtain a delayed audio.

[0109] The audio reverberation device provided in this application embodiment can realize the various processes implemented in the aforementioned method embodiments, and will not be described again here to avoid repetition.

[0110] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0111] Figure 5 A schematic diagram of the hardware structure of the electronic device provided in an embodiment of this application is shown.

[0112] The electronic device may include a processor 501 and a memory 502 storing computer program instructions.

[0113] Specifically, the processor 501 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this application.

[0114] Memory 502 may include mass storage for data or instructions. For example, and not limitingly, memory 502 may include a hard disk drive (HDD), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 502 may include removable or non-removable (or fixed) media. Where appropriate, memory 502 may be internal or external to the integrated gateway disaster recovery device. In a particular embodiment, memory 502 is non-volatile solid-state memory.

[0115] Memory may include read-only memory (ROM), random access memory (RAM), disk storage media devices, optical storage media devices, flash memory devices, and electrical, optical, or other physical / tangible memory storage devices. Therefore, typically, memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the methods according to one aspect of this disclosure.

[0116] The processor 501 implements any of the audio reverberation methods described in the above embodiments by reading and executing computer program instructions stored in the memory 502.

[0117] In one example, the electronic device may also include a communication interface 503 and a bus 510. Wherein, as... Figure 5 As shown, the processor 501, memory 502, and communication interface 503 are connected through bus 510 and complete communication with each other.

[0118] The communication interface 503 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of this application.

[0119] Bus 510 includes hardware, software, or both, that couples components of an electronic device together. For example, and not limitingly, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), HyperTransport (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Microchannel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local (VLB) bus, or other suitable buses, or combinations of two or more of these. Where appropriate, bus 510 may include one or more buses. Although specific buses are described and illustrated in embodiments of this application, this application contemplates any suitable bus or interconnect.

[0120] Furthermore, in conjunction with the audio reverberation methods in the above embodiments, this application embodiment can provide a computer-readable storage medium for implementation. This computer-readable storage medium stores computer program instructions; when these computer program instructions are executed by a processor, they implement any of the audio reverberation methods in the above embodiments.

[0121] Furthermore, in conjunction with the audio reverberation methods in the above embodiments, this application embodiment can provide a computer program product for implementation. When the instructions in this computer program product are executed by the processor of an electronic device, the electronic device performs and implements any of the audio reverberation methods in the above embodiments.

[0122] In addition, in conjunction with the audio reverberation method in the above embodiments, this application embodiment can provide a vehicle, which includes at least one of the following: the audio reverberation device as described above; the electronic device as described above; and the computer-readable storage medium as described above.

[0123] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.

[0124] The functional modules shown in the above-described block diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. Programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0125] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0126] The foregoing flowcharts and / or block diagrams describing audio reverberation methods, apparatuses, electronic devices, media, products, and vehicles according to embodiments of this disclosure have described various aspects of the present disclosure. It should be understood that each block in the flowcharts and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to create a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowcharts and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by dedicated hardware performing the specified functions or actions, or can be implemented by a combination of dedicated hardware and computer instructions.

[0127] The above description is merely a specific implementation of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. An audio reverberation method, characterized in that, include: The target reverberation time of the audio to be reverberated is determined based on the decay rate of the ambient sound features corresponding to the target audio reverberation scene in each frequency band of the audio to be reverberated. The delay parameters of each delay line in the feedback delay network are determined based on the target reverberation time, wherein the feedback delay network includes at least multiple delay lines, and each delay line is equipped with a delay unit and a state variable filter. Based on the target reverberation time and the delay parameters corresponding to each delay line, the coefficients of the state variable filter on each delay line are updated to obtain the updated state variable filter. The corresponding delayed audio is attenuated by the updated state variable filter to obtain the output audio corresponding to each delay line, wherein the delayed audio is the audio obtained after delaying the audio to be reverberated by the delay unit on the corresponding delay line; The output audio from the multiple delay lines in the feedback delay network and the audio to be reverberated are superimposed to obtain the target audio corresponding to the target audio reverberation scene.

2. The method according to claim 1, characterized in that, The target reverberation time of the audio to be reverberated is determined based on the decay rate of the ambient sound features corresponding to the target audio reverberation scene at each frequency band in the audio to be reverberated, including: Obtain a target impulse response file that matches the target audio reverberation scene from multiple impulse response files, wherein the impulse response file includes the environmental sound features of the corresponding audio reverberation scene, and the environmental sound features are used to characterize the signal reflection data and signal attenuation data of the impulse signal in the environment of the audio reverberation scene; Calculate the attenuation rate of the ambient sound features in the target impulse response file across multiple frequency bands; The reverberation time corresponding to each frequency band is determined based on the attenuation rate of the environmental sound characteristics in the multiple frequency bands; The target reverberation time corresponding to the audio to be reverberated is determined based on the frequency band corresponding to the audio to be reverberated.

3. The method according to claim 1, characterized in that, Determine the delay parameters of each delay line in the feedback delay network based on the target reverberation time, including: Based on the target reverberation time and the number of delay lines in the multi-path delay line, determine the total delay parameters corresponding to the multi-path delay line; The delay parameter corresponding to each delay line is determined based on the total delay parameter, wherein the total delay parameter is the sum of the delay parameters corresponding to the multiple delay lines, and the delay parameters corresponding to the multiple delay lines are coprime.

4. The method according to claim 1, characterized in that, Based on the target reverberation time and the delay parameters corresponding to each delay line, the coefficients of the state variable filter on each delay line are updated to obtain the updated state variable filter, including: Based on the target reverberation time and the delay parameters corresponding to the first delay line, the frequency response of the first state variable filter on the first delay line is determined, wherein the first delay line is any one of the multiple delay lines, and the first state variable filter is a filter deployed on the first delay line. Calculate the amplitude response corresponding to the frequency response; The magnitude response is inversely calculated to obtain the target filter coefficients corresponding to the first state variable filter; The initial filter coefficients of the first state variable filter are updated to the target filter coefficients to obtain the updated state variable filter.

5. The method according to claim 4, characterized in that, Based on the target reverberation time and the delay parameters corresponding to the first delay line, determine the frequency response of the first state variable filter on the first delay line, including: Obtain the sampling rate of the first state variable filter; The attenuation response of the first state variable filter is determined based on the sampling rate and the target reverberation time; The product of the delay parameter corresponding to the first delay line and the attenuation response is determined as the frequency response of the first state variable filter.

6. The method according to claim 4, characterized in that, The state variable filter includes a low-pass filter, a high-pass filter, and a band-pass filter. The updated state variable filter is obtained by updating the initial filter coefficients of the first state variable filter to the target filter coefficients, including: The amplitude response is inversely calculated to obtain the cutoff frequency, resonance parameters, and state values ​​of the first state variable filter. The transfer function of the bandpass filter is determined based on the cutoff frequency, the resonance parameter, and the state value of the first state variable filter. The transfer function of the low-pass filter is determined based on the cutoff frequency, the state value of the first state variable filter, and the coefficients of the bandpass filter. The transfer function of the high-pass filter is determined based on the resonance parameters, the coefficients of the low-pass filter, and the coefficients of the band-pass filter. The weighted values ​​of the target filter coefficients, the transfer functions of the bandpass filter, the lowpass filter, and the highpass filter are calculated to obtain the updated state variable filter transfer function.

7. The method according to claim 1, characterized in that, The feedback delay network further includes a feedback unit connected between the input and output terminals of the multiple delay lines. Before attenuating the corresponding delayed audio through the updated state variable filter to obtain the output audio corresponding to each delay line, the method further includes: Obtain the first audio output from the first delay line fed back by the feedback unit, wherein the first delay line is any one of the multiple delay lines; The audio to be reverberated is superimposed on the first audio to obtain the second audio. The second audio is delayed by using the delay unit in the first delay line to obtain the delayed audio.

8. An audio reverberation device, characterized in that, include: The reverberation time determination module is used to determine the target reverberation time of the audio to be reverberated based on the decay rate of the environmental sound characteristics corresponding to the target audio reverberation scene in each frequency band of the audio to be reverberated. The parameter calculation module is used to determine the delay parameters of each delay line in the feedback delay network based on the target reverberation time, wherein the feedback delay network includes at least multiple delay lines, and each delay line is equipped with a delay unit and a state variable filter. The coefficient update module is used to update the coefficients of the state variable filter on each delay line according to the target reverberation time and the delay parameters corresponding to each delay line, so as to obtain the updated state variable filter. The attenuation module is used to attenuate the corresponding delayed audio through the updated state variable filter to obtain the output audio corresponding to each delay line, wherein the delayed audio is the audio obtained after delaying the audio to be reverberated through the delay unit on the corresponding delay line; The reverb module is used to superimpose the output audio from the multiple delay lines in the feedback delay network and the audio to be reverbed to obtain the target audio corresponding to the target audio reverb scene.

9. An electronic device, characterized in that, Electronic devices include: processors and memory storing computer program instructions; When the processor executes the computer program instructions, it implements the audio reverberation method as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, A computer-readable storage medium stores computer program instructions that, when executed by a processor, implement the audio reverberation method as described in any one of claims 1-7.

11. A computer program product, characterized in that, When the instructions in the computer program product are executed by the processor of the electronic device, the electronic device causes the electronic device to perform the audio reverberation method as described in any one of claims 1-7.

12. A vehicle, characterized in that, Includes at least one of the following: The audio reverberation device as described in claim 8; The electronic device as described in claim 9; The computer-readable storage medium as claimed in claim 10.

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