Audio equalization method and device, equipment and storage medium

Abstract

The invention discloses an audio equalization method and device, equipment and a storage medium, and relates to the technical field of audio. The method comprises the following steps: acquiring an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter comprises at least one frequency point needing to be adjusted and a gain corresponding to the at least one frequency point; filtering the input audio signal through a filter bank to obtain a plurality of audio sub-bands; according to the at least one frequency point and the gain corresponding to the at least one frequency point, obtaining delay time corresponding to the plurality of audio sub-bands; performing delay processing on the plurality of audio sub-bands according to the delay time corresponding to the plurality of audio sub-bands to obtain a plurality of delayed audio sub-bands; and synthesizing the plurality of delayed audio sub-bands to obtain an output audio signal. According to the invention, the influence on the energy of the audio signal is avoided, the normal output of the audio signal is ensured, the equalization adjustment of the audio signal is realized, and the audio equalization quality is improved.

Description

Technical Field

[0001] The present application relates to the field of audio technology, and in particular to an audio equalization method, device, equipment and storage medium. Background Art

[0002] The equalization adjustment of audio signals (audio equalizer) is usually achieved using IIR (Infinite Impulse Response) or FIR (Finite Impulse Response) filters, which controls the increase in some frequency points in the audio signal to amplify or attenuate the amplitude of the audio signal of the corresponding frequency.

[0003] In the related art, in the music player program, after the audio decoder decodes the audio file into PCM (Pulse Code Modulation) data, it needs to be balanced and adjusted, and then the balanced PCM data is sent to the amplifier module through the audio output interface of the operating system. The energy of the digital sound source is usually standardized, such as the CD (Compact Disc) standard, the MP3 (Moving Picture Experts Group Audio Layer III) with a label, Dolby, AAC (Advanced Audio Coding, advanced audio coding), etc., most of which are close to the full amplitude of the audio digital signal. Therefore, if the user wants to apply an equalization adjustment with a gain of 10dB at a frequency of 120Hz, there is a high probability that the audio digital signal will overflow, and then the audio signal compression effect (such as using dynamic range compression to control signal overflow after equalization adjustment) or clipping distortion will appear. An effective solution is to attenuate the volume of the audio digital signal (reduce the audio energy) before making the equalization adjustment, and then make the equalization adjustment. Finally, the power amplifier module is required to cooperate (increase the gain of the audio analog signal, or even increase the power supply voltage of the audio analog signal amplification circuit) to compensate for the previous attenuation of the audio digital signal volume.

[0004] However, the above audio equalization method may need to modify the hardware circuit in order to compensate for the defect of audio energy, which costs too much. Summary of the invention

[0005] The embodiment of the present application provides an audio equalization method, device, equipment and storage medium. The technical solution provided by the embodiment of the present application is as follows:

[0006] According to one aspect of an embodiment of the present application, there is provided an audio equalization method, the method comprising:

[0007] Acquire an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter includes at least one frequency point to be adjusted and a gain corresponding to the at least one frequency point, wherein the gain is used to amplify the frequency of the frequency point;

[0008] Filtering the input audio signal through a filter bank to obtain a plurality of audio sub-bands, wherein the filter bank includes a low-pass filter, a high-pass filter and at least one band-pass filter, wherein the at least one band-pass filter is a band-pass filter divided based on a critical band of a Bark scale;

[0009] Obtaining delay times corresponding to the plurality of audio sub-bands according to the at least one frequency point and the gains corresponding to the at least one frequency point, wherein the delay times are time for unifying auditory perception of the audio sub-bands;

[0010] Delaying the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands to obtain multiple delayed audio sub-bands;

[0011] The delayed multiple audio sub-bands are synthesized to obtain an output audio signal.

[0012] According to one aspect of an embodiment of the present application, there is provided an audio equalization device, the device comprising:

[0013] A signal acquisition module, used to acquire an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter includes at least one frequency point to be adjusted and a gain corresponding to the at least one frequency point, wherein the gain is used to amplify the frequency of the frequency point;

[0014] a signal filtering module, configured to filter the input audio signal through a filter bank to obtain a plurality of audio sub-bands, wherein the filter bank comprises a low-pass filter, a high-pass filter and at least one band-pass filter, wherein the at least one band-pass filter is a band-pass filter divided based on a critical frequency band of a Bark scale;

[0015] a delay determination module, configured to obtain delay times corresponding to the plurality of audio sub-bands respectively according to the at least one frequency point and the gains respectively corresponding to the at least one frequency point, wherein the delay times are time for unifying auditory perception of the audio sub-bands;

[0016] a delay processing module, configured to perform delay processing on the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands, so as to obtain multiple delayed audio sub-bands;

[0017] The sub-band synthesis module is used to synthesize the delayed multiple audio sub-bands to obtain an output audio signal.

[0018] According to one aspect of an embodiment of the present application, a computer device is provided, the computer device comprising a processor and a memory, the memory storing a computer program, the computer program being loaded and executed by the processor to implement the above-mentioned audio equalization method.

[0019] According to one aspect of an embodiment of the present application, a computer-readable storage medium is provided, in which a computer program is stored. The computer program is loaded and executed by a processor to implement the above-mentioned audio equalization method.

[0020] According to one aspect of an embodiment of the present application, a computer program product is provided. The computer program product includes a computer program. The computer program is loaded and executed by a processor to implement the above-mentioned audio equalization method.

[0021] The technical solution provided in the embodiments of the present application can bring the following beneficial effects:

[0022] By filtering the input audio signal to obtain multiple audio sub-bands, the gain of the frequency point in the equalization adjustment process of the audio signal can be converted into the delay time corresponding to the audio sub-band, avoiding directly amplifying or attenuating the amplitude of the audio signal, thereby avoiding affecting the energy of the audio signal, causing the audio signal to overflow and the compression effect or clipping distortion, and realizing the equalization adjustment of the audio signal while ensuring the normal output of the audio signal, and by calculating the delay time corresponding to the audio sub-band and delaying each audio sub-band, the delayed audio sub-band unifies the auditory perception time of the audio sub-band, so that the auditory perception of the output audio signal at each frequency is consistent, and the quality of audio equalization is improved. In addition, since the technical method provided by the present application is easy to implement in operation, it avoids changing the hardware circuit, reduces the implementation steps of audio equalization, saves the resources required for audio equalization, improves the efficiency of audio equalization, and avoids the excessive cost of compensating for the defects of audio energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of an implementation environment of a solution provided by an embodiment of the present application;

[0024] Figure 2 is a flow chart of an audio equalization method provided by an embodiment of the present application;

[0025] Figure 3 It is a flowchart of an audio equalization method provided by an embodiment of the present application;

[0026] Figure 4 is a schematic diagram of allocating a first frequency point to each audio sub-band gain value provided by an embodiment of the present application;

[0027] Figure 5 is a block diagram of an audio equalization device provided by an embodiment of the present application;

[0028] Figure 6 It is a structural block diagram of a computer device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0030] Please refer to Figure 1 , which shows a schematic diagram of a solution implementation environment provided by an embodiment of the present application. The solution implementation environment can be implemented as an audio equalization system. The solution implementation environment may include: a terminal device 10 and a server 20.

[0031] The number of terminal devices 10 can be one or more. The terminal device 10 can be an electronic device such as a mobile phone, a tablet computer, a laptop computer, a desktop computer, a game console, an e-book reader, a multimedia player, a wearable device, an intelligent voice interaction device, a smart home appliance, a vehicle terminal, an aircraft, etc.

[0032] The terminal device 10 may be installed with a client of a target application, and the target application has the function of performing equalization adjustment on the input audio signal. The user may input the audio signal and the equalization adjustment parameters in the target application, and realize the equalization adjustment of the audio signal based on at least one frequency point to be adjusted and the gain corresponding to at least one frequency point. The present application does not limit the type of the target application, including but not limited to music applications, video applications, web applications, etc. Optionally, the target application may be an application that needs to be downloaded and installed, or may be a click-to-use application, and the present application does not limit this.

[0033] The server 20 is used to provide background services for the client of the target application installed and running in the terminal device 10. For example, the server 20 can be the background server of the above application. The server 20 can be an independent physical server, or a server cluster composed of multiple servers, or a cloud computing service center. Optionally, the server 20 provides background services for the applications in multiple terminal devices 10 at the same time. The terminal device 10 and the server 20 can communicate with each other through the network.

[0034] In an embodiment of the present application, a user inputs an audio signal to be equalized and an equalization adjustment parameter in a target application, and a computer device obtains an input audio signal, as well as at least one frequency point to be adjusted and a gain corresponding to at least one frequency point. The input audio signal is filtered through multiple filters in a filter bank to obtain multiple audio sub-bands, and the delay times corresponding to the multiple audio sub-bands are calculated based on the gains corresponding to the at least one frequency point and the at least one frequency point, and the multiple audio sub-bands are delayed based on the delay time, and the multiple audio sub-bands after delay are synthesized to obtain an output audio signal.

[0035] Please refer to Figure 2 , which shows a flow chart of an audio equalization method provided by an embodiment of the present application. The execution subject of each step of the method may be a computer device. The method may include at least one of the following steps 210 to 250:

[0036] Step 210: acquiring an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter includes at least one frequency point to be adjusted and a gain corresponding to the at least one frequency point, wherein the gain is used to amplify the frequency of the frequency point.

[0037] The input audio signal refers to an input audio digital signal, which is PCM data obtained by decoding an audio file through an audio decoder.

[0038] The equalization adjustment parameter is a parameter input by the user for equalization adjustment of the input audio signal. The equalization adjustment parameter includes at least one frequency point that needs to be adjusted and the gain corresponding to at least one frequency point. The frequency point is used to indicate the position where the signal amplitude needs to be adjusted in the input audio signal, and the gain corresponding to the frequency point is used to control the increase of the frequency point to amplify or attenuate the amplitude of the audio signal at the frequency point. Exemplarily, if the gain corresponding to the frequency point is 10dB, it means that the amplitude of the audio signal at the frequency point is amplified by 10^(10dB / 20)=3.16 times. If the gain corresponding to the frequency point is -10dB, it means that the amplitude of the audio signal at the frequency point is amplified by 10^(-10dB / 20)=0.316 times.

[0039] Step 220: Filter the input audio signal through a filter bank to obtain multiple audio sub-bands, where the filter bank includes a low-pass filter, a high-pass filter and at least one band-pass filter, and the at least one band-pass filter is a band-pass filter divided based on a critical band of a Bark scale.

[0040] The low-pass filter is used to obtain audio signals in the input audio signal whose frequency is lower than the cutoff frequency of the low-pass filter, the high-pass filter is used to obtain audio signals in the input audio signal whose frequency is higher than the cutoff frequency of the high-pass filter, and the band-pass filter is used to obtain audio signals in the input audio signal within a frequency band.

[0041] The filter bank can be an IIR filter bank with high stopband attenuation, or a FIR filter bank with high stopband attenuation, which is not limited in this application. Exemplarily, the filter bank can be designed with a window function to obtain 1 FIR low-pass filter, 1 FIR high-pass filter and 23 FIR band-pass filters, the window function adopts a Blackman window, and the filter order adopts 513 orders.

[0042] In some embodiments, the performance of each filter included in the filter bank satisfies that the stopband attenuation exceeds 60 dB and the slope exceeds 36 dB / oct.

[0043] In some embodiments, at least one bandpass filter is a bandpass filter divided based on critical bands of the Bark scale.

[0044] Exemplarily, the filter bank includes 25 filters, the cutoff frequency corresponding to the low-pass filter is 100 Hz, the cutoff frequency corresponding to the high-pass filter is 15500 Hz, and the low cutoff frequency and high cutoff frequency of the remaining 23 band-pass filters correspond to the starting frequency and cutoff frequency of No. 2 to No. 24 of the critical frequency band of the Bark scale, that is, the frequency band range of the first band-pass filter is 100-200 Hz, the frequency band range of the second band-pass filter is 200-300 Hz, ..., and the frequency band range of the 23rd band-pass filter is 12000-15500 Hz.

[0045] Exemplarily, if the filter bank includes 25 filters, the input audio signal is filtered by the filter bank to obtain 25 audio subbands.

[0046] Since delaying the signal of the audio sub-band and then synthesizing PCM will cause large phase distortion at the boundary frequency of each audio sub-band, if the filter crossover point is arbitrarily selected, the distortion may appear in the frequency range that is most obvious to human auditory perception. When the Bark scale is selected as the crossover point, the phase distortion is concentrated on the boundaries of each Bark frequency band. The Bark scale is divided according to human auditory perception, which can effectively solve the problem of phase distortion.

[0047] Step 230: Obtain delay times corresponding to the plurality of audio sub-bands according to at least one frequency point and the gain corresponding to the at least one frequency point. The delay time is a time for unifying auditory perception of the audio sub-bands.

[0048] According to psychoacoustics, for a composite audio signal composed of multiple frequencies, the frequency signal heard first is more obvious to the auditory perception. Therefore, it is necessary to determine the delay time corresponding to each audio sub-band based on at least one frequency point and the gain corresponding to at least one frequency point respectively, convert the gain into delay time without changing the energy of the audio signal, and align multiple audio sub-bands through delay time, thereby achieving balanced adjustment of the audio signal.

[0049] The specific process of determining the delay time corresponding to the audio sub-band may refer to the following embodiment and will not be introduced here.

[0050] Step 240: Delay the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands to obtain multiple delayed audio sub-bands.

[0051] The delayer may delay the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands to obtain the multiple audio sub-bands after delay. For example, the number of audio samples corresponding to the delay time may be determined according to the interval time of the audio samples included in the delay time, so that the audio sample value within the delay time is assigned to 0 to obtain the audio sub-band after delay.

[0052] Exemplarily, the audio sampling values ​​at each position of the audio subband are expressed as (1, 1, 0, 1, 1, 1), and the delay time includes the interval time between two audio samples. Then, the audio sampling values ​​at each position of the delayed audio subband are expressed as (0, 0, 1, 1, 0, 1, 1, 1).

[0053] Step 250: synthesize the delayed multiple audio sub-bands to obtain an output audio signal.

[0054] In some embodiments, step 250 includes at least one of sub-steps 251 - 252 .

[0055] Sub-step 251, adding the audio sampling values ​​at the same position in the multiple audio sub-bands after delay to obtain audio sub-signals corresponding to the multiple positions.

[0056] Exemplarily, if the filter bank includes 25 filters, 25 audio subbands are obtained by filtering, and the 25 delayed audio subbands are S1, S2, S3, ..., S24, and S25, respectively. Each audio subband contains at least one audio sample value, S1[0] represents the first audio sample value in the audio subband S1, S1[1] represents the second audio sample value in the audio subband S1, S2[0] represents the first audio sample value in the audio subband S2, and so on. To calculate the audio subsignal corresponding to the first position, it is necessary to add the audio sample values ​​at the first position in the 25 delayed audio subbands to obtain the audio subsignal corresponding to the first position PCM[0]=S1[0]+S2[0]+S3[0]+...+S25[0]. Similarly, the audio sub-signal PCM[1] corresponding to the second position is S1[1]+S2[1]+S3[1]+…+S25[1], …, and the audio sub-signal PCM[n] corresponding to the nth position is S1[n]+S2[n]+S3[n]+…+S25[n], where n is a positive integer.

[0057] Sub-step 252, obtaining an output audio signal according to the audio sub-signals corresponding to the multiple positions.

[0058] By combining the audio sub-signals corresponding to the multiple positions, an output audio signal can be obtained.

[0059] Exemplarily, the audio sub-signal PCM[0] corresponding to the first position, the audio sub-signal PCM[1] corresponding to the second position, ..., the audio sub-signal PCM[n] corresponding to the nth position are combined to obtain an output audio signal PCM, which is a composite audio signal after the audio sub-bands are synthesized.

[0060] The above method realizes the balanced adjustment of the audio signal without changing the energy of the audio signal, and achieves the consistency of the auditory experience of each audio sub-band.

[0061] Figure 3 The flowchart of the audio equalization method is shown. First, the user inputs an audio signal and an equalization adjustment parameter, and the filter group filters the input audio signal to obtain multiple audio sub-bands. Then, according to at least one frequency point to be adjusted and the gain corresponding to at least one frequency point included in the equalization adjustment parameter, the delay time corresponding to each audio sub-band is determined. According to the delay time, the multiple audio sub-bands are delayed respectively to obtain delayed audio sub-bands. The multiple delayed audio sub-bands are synthesized to obtain an output audio signal.

[0062] The technical solution provided by the embodiment of the present application obtains multiple audio sub-bands by filtering the input audio signal, so that the gain of the frequency point in the equalization adjustment process of the audio signal can be converted into the delay time corresponding to the audio sub-band, avoiding directly amplifying or attenuating the amplitude of the audio signal, thereby avoiding affecting the energy size of the audio signal, causing the audio signal to overflow and the compression effect or clipping distortion, and realizing the equalization adjustment of the audio signal while ensuring the normal output of the audio signal, and by calculating the delay time corresponding to the audio sub-band and delaying each audio sub-band, the delayed audio sub-band unifies the auditory perception time of the audio sub-band, so that the auditory perception of the output audio signal at each frequency is consistent, and the quality of audio equalization is improved. In addition, since the technical method provided by the present application is easy to implement in operation, it avoids changing the hardware circuit, reduces the implementation steps of audio equalization, saves the resources required for audio equalization, improves the efficiency of audio equalization, and avoids the excessive cost spent to make up for the defects of audio energy.

[0063] In some embodiments, step 230 includes at least one of sub-steps 231 - 232 .

[0064] Sub-step 231, obtaining gain values ​​corresponding to a plurality of audio sub-bands respectively according to at least one frequency point and the gain respectively corresponding to the at least one frequency point.

[0065] It should be noted that the initial gain values ​​of the multiple audio sub-bands are all 0.

[0066] In some embodiments, step 231 includes at least one of sub-steps 2311 - 2313 .

[0067] Sub-step 2311: for a first frequency point among the at least one frequency point, obtain a first audio sub-band and a second audio sub-band from multiple audio sub-bands, the frequency of the first frequency point is greater than or equal to the center frequency of the first audio sub-band, and the frequency of the first frequency point is less than the center frequency of the second audio sub-band.

[0068] The first frequency point is used to indicate a first position in the input audio signal where the signal amplitude needs to be adjusted. The frequency of the first frequency point is represented as F1, and the gain corresponding to the first frequency point is represented as G1.

[0069] The center frequency of an audio subband refers to the average value of at least one audio sample value contained in the audio subband, the first audio subband is represented by S1, the second audio subband is represented by S2, the center frequency of the first audio subband is C1, and the center frequency of the second audio subband is C2. Then C1≤F1<C2.

[0070] Sub-step 2312, according to the center frequency of the first audio sub-band, the center frequency of the second audio sub-band, the frequency of the first frequency point and the gain corresponding to the first frequency point, obtain the sub-gain value of the first frequency point allocated to the first audio sub-band and the sub-gain value of the first frequency point allocated to the second audio sub-band.

[0071] In some embodiments, the distance corresponding to the first audio sub-band is obtained according to the center frequency of the first audio sub-band, the center frequency of the second audio sub-band and the frequency of the first frequency point; and the sub-gain value of the first frequency point allocated to the first audio sub-band is obtained according to the distance corresponding to the first audio sub-band and the gain corresponding to the first frequency point.

[0072] According to the center frequency C1 of the first audio sub-band, the center frequency C2 of the second audio sub-band, and the frequency F1 of the first frequency point, a distance R1 corresponding to the first audio sub-band is obtained. According to the distance R1 corresponding to the first audio sub-band and the gain G1 corresponding to the first frequency point, a sub-gain value SG1 allocated to the first audio sub-band at the first frequency point is obtained.

[0073] Exemplarily, R1 = (F1 - C1) / (C2 - C1), SG1 = (1 - R1)*G1.

[0074] In some embodiments, the distance corresponding to the second audio sub-band is obtained according to the center frequency of the first audio sub-band, the center frequency of the second audio sub-band and the frequency of the first frequency point; and the sub-gain value of the first frequency point allocated to the second audio sub-band is obtained according to the distance corresponding to the second audio sub-band and the gain corresponding to the first frequency point.

[0075] According to the center frequency C1 of the first audio sub-band, the center frequency C2 of the second audio sub-band, and the frequency F1 of the first frequency point, a distance R2 corresponding to the second audio sub-band is obtained. According to the distance R2 corresponding to the second audio sub-band and the gain G1 corresponding to the first frequency point, a sub-gain value SG2 allocated from the first frequency point to the second audio sub-band is obtained.

[0076] Exemplarily, R2 = (C2 - F1) / (C2 - C1), SG2 = (1 - R2) * G1.

[0077] The above sub-steps 2311 to 2312 are looped to determine multiple groups of audio sub-bands that meet the frequency requirements of the first frequency point from the multiple audio sub-bands, and the sub-gain values ​​assigned to each audio sub-band at the first frequency point are calculated respectively. For example, for the first frequency point, the first audio sub-band and the third audio sub-band can also be obtained from the multiple audio sub-bands, the frequency of the first frequency point is greater than or equal to the center frequency of the first audio sub-band, and the frequency of the first frequency point is less than the center frequency of the third audio sub-band, then another sub-gain value assigned to the first audio sub-band at the first frequency point and the sub-gain value assigned to the third audio sub-band at the first frequency point are calculated. In this case, the other sub-gain value assigned to the first audio sub-band at the first frequency point needs to be added to the sub-gain value assigned to the first audio sub-band at the first frequency point that has been obtained, and the sub-gain value assigned to the first audio sub-band at the first frequency point is obtained by looping and superimposing.

[0078] Figure 4 The process of allocating the sub-gain values ​​of the first frequency point to each audio sub-band is shown. For the first frequency point, the first audio sub-band S1 and the second audio sub-band S2 that meet the frequency requirements are obtained from multiple audio sub-bands. According to the center frequency of the first audio sub-band S1, the center frequency of the second audio sub-band S2 and the frequency F1 of the first frequency point, the distance R1 corresponding to the first audio sub-band and the distance R2 corresponding to the second audio sub-band are obtained, and then the sub-gain value SG1 allocated to the first audio sub-band at the first frequency point and the sub-gain value SG2 allocated to the second audio sub-band at the first frequency point are obtained.

[0079] Sub-step 2313: obtaining a gain value corresponding to the first audio sub-band according to the sub-gain values ​​respectively allocated to the first audio sub-band at least one frequency point, and obtaining a gain value corresponding to the second audio sub-band according to the sub-gain values ​​respectively allocated to the second audio sub-band at least one frequency point.

[0080] For example, at least one frequency point is respectively assigned to the sub-gain values ​​of the first audio sub-band and the gain value corresponding to the first audio sub-band is obtained by adding the sub-gain values ​​of the second audio sub-band and the gain value corresponding to the second audio sub-band is obtained by adding the sub-gain values ​​of the second audio sub-band and the gain value corresponding to the second audio sub-band.

[0081] Sub-step 232, obtaining delay times corresponding to the plurality of audio sub-bands respectively according to the gain values ​​corresponding to the plurality of audio sub-bands respectively.

[0082] According to psychoacoustics, the gain value corresponding to the audio sub-band is converted into the delay time corresponding to the audio sub-band to unify the auditory perception time of the audio sub-band and make the auditory perception of the output audio signal consistent at each frequency.

[0083] In some embodiments, step 232 includes at least one of sub-steps 2321 - 2323 .

[0084] Sub-step 2321: Obtain a maximum gain value among the gain values ​​corresponding to the multiple audio sub-bands.

[0085] The maximum gain value among the gain values ​​corresponding to the multiple audio sub-bands is recorded as Gmax.

[0086] Sub-step 2322: For any audio sub-band, subtract the maximum gain value from the gain value corresponding to the audio sub-band to obtain a normalized gain value corresponding to the audio sub-band.

[0087] The maximum gain value is subtracted from the gain values ​​corresponding to the multiple audio sub-bands respectively, and the gain value of the audio sub-band is normalized to a maximum value of 0, that is, the maximum value of the normalized gain value corresponding to the audio sub-band is 0.

[0088] Sub-step 2323, obtaining the delay time corresponding to the audio sub-band according to the center frequency and the normalized gain value of the audio sub-band.

[0089] According to the center frequency of the audio sub-band, the normalized gain value corresponding to the audio sub-band is converted into the delay time corresponding to the audio sub-band. The conversion method is: for an audio sub-band S, its center frequency is C, and the gain is SG, then the period length corresponding to the signal delay C of the audio sub-band is calculated for every 1 dB, and then the delay time corresponding to the audio sub-band S is obtained according to the number of periods required to be delayed.

[0090] Sub-step 2323 includes the following steps.

[0091] 1. According to the center frequency of the audio sub-band, the period length of the audio sub-band is obtained.

[0092] The period duration of the audio subband=1 / the center frequency of the audio subband. Exemplarily, for the audio subband S, if the center frequency of the audio subband S is 150 Hz, the period duration of the audio subband S is 1 / 150=0.00667 seconds.

[0093] 2. According to the linear mapping relationship between the normalized gain value and the number of delay cycles, the number of delay cycles corresponding to the normalized gain value is obtained.

[0094] The number of delay cycles is used to indicate the number of cycles that the audio subband needs to be delayed. There is a preset linear mapping relationship between the normalized gain value and the number of delay cycles. This application does not limit the linear mapping relationship between the normalized gain value and the number of delay cycles.

[0095] For example, if the normalized gain value of the audio subband S is -10 dB and the number of delay cycles is 10, it means that the audio subband needs to be delayed by 10 cycles. If the normalized gain value of the audio subband S is -20 dB and the number of delay cycles is 20, it means that the audio subband needs to be delayed by 20 cycles.

[0096] 3. According to the number of delay cycles corresponding to the normalized gain value and the cycle length of the audio sub-band, the delay time corresponding to the audio sub-band is obtained.

[0097] Exemplarily, the delay time corresponding to the audio sub-band is obtained by multiplying the number of delay periods corresponding to the normalized gain value by the period length of the audio sub-band.

[0098] For example, if the normalized gain value of the audio subband S is -10 dB and the number of delay cycles is 10, the delay time corresponding to the audio subband is 0.0667 seconds. If the normalized gain value of the audio subband S is -20 dB and the number of delay cycles is 20, the delay time corresponding to the audio subband is 0.1334 seconds.

[0099] In some embodiments, for a regularized gain value having a decimal, a rounding method toward negative infinity may be used to perform rounding, and the number of delay cycles corresponding to the normalized gain value may be determined according to the rounded normalized gain value. For example, if the normalized gain value of the audio subband S is -10.5 dB, the normalized gain value obtained by rounding the normalized gain value is -11 dB, and correspondingly, the number of delay cycles obtained according to the rounded normalized gain value is 11.

[0100] The gain value corresponding to each audio sub-band is calculated by the above method, and the gain value corresponding to the audio sub-band is converted into the delay time corresponding to the audio sub-band, thereby achieving equalization adjustment of the audio signal without changing the energy of the audio signal, while ensuring the normal output of the audio signal, improving the quality of audio equalization, and bringing better audio hearing effects to users.

[0101] The following is an embodiment of the device of the present application, which can be used to execute the embodiment of the method of the present application. For details not disclosed in the embodiment of the device of the present application, please refer to the embodiment of the method of the present application.

[0102] Please refer to Figure 5 , which shows a block diagram of an audio equalization device provided by an embodiment of the present application. The device has the function of implementing the above-mentioned audio equalization method, and the function can be implemented by hardware, or by hardware executing corresponding software. The device can be the computer device introduced above, or it can be set in a computer device. Figure 5 As shown, the apparatus 500 may include: a signal acquisition module 510 , a signal filtering module 520 , a delay determination module 530 , a delay processing module 540 and a sub-band synthesis module 550 .

[0103] The signal acquisition module 510 is used to acquire an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter includes at least one frequency point to be adjusted and a gain corresponding to the at least one frequency point, wherein the gain is used to amplify the frequency of the frequency point.

[0104] The signal filtering module 520 is used to filter the input audio signal through a filter bank to obtain multiple audio sub-bands, wherein the filter bank includes a low-pass filter, a high-pass filter and at least one band-pass filter, and the at least one band-pass filter is a band-pass filter divided based on the critical frequency band of the Bark scale.

[0105] The delay determination module 530 is used to obtain the delay time corresponding to the multiple audio sub-bands according to the at least one frequency point and the gain corresponding to the at least one frequency point, and the delay time is the time used to unify the auditory perception of the audio sub-bands.

[0106] The delay processing module 540 is configured to perform delay processing on the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands to obtain multiple delayed audio sub-bands.

[0107] The sub-band synthesis module 550 is used to synthesize the delayed multiple audio sub-bands to obtain an output audio signal.

[0108] In some embodiments, the delay determination module 530 includes:

[0109] The gain determination unit is used to obtain the gain values ​​corresponding to the multiple audio sub-bands respectively according to the at least one frequency point and the gains respectively corresponding to the at least one frequency point.

[0110] The delay determination unit is used to obtain the delay times corresponding to the multiple audio sub-bands respectively according to the gain values ​​corresponding to the multiple audio sub-bands respectively.

[0111] In some embodiments, the gain determination unit is configured to:

[0112] For a first frequency point among the at least one frequency point, obtaining a first audio sub-band and a second audio sub-band from the multiple audio sub-bands, wherein a frequency of the first frequency point is greater than or equal to a center frequency of the first audio sub-band, and a frequency of the first frequency point is less than a center frequency of the second audio sub-band;

[0113] obtaining, according to the center frequency of the first audio sub-band, the center frequency of the second audio sub-band, the frequency of the first frequency point, and the gain corresponding to the first frequency point, a sub-gain value of the first frequency point allocated to the first audio sub-band and a sub-gain value of the first frequency point allocated to the second audio sub-band;

[0114] A gain value corresponding to the first audio sub-band is obtained according to the sub-gain values ​​respectively allocated to the first audio sub-band at the at least one frequency point, and a gain value corresponding to the second audio sub-band is obtained according to the sub-gain values ​​respectively allocated to the second audio sub-band at the at least one frequency point.

[0115] In some embodiments, the gain determination unit is configured to:

[0116] obtaining, according to a center frequency of the first audio sub-band, a center frequency of the second audio sub-band, and a frequency of the first frequency point, a distance corresponding to the first audio sub-band and a distance corresponding to the second audio sub-band;

[0117] obtaining a sub-gain value allocated to the first audio sub-band by the first frequency point according to the distance corresponding to the first audio sub-band and the gain corresponding to the first frequency point;

[0118] A sub-gain value of the first frequency point allocated to the second audio sub-band is obtained according to the distance corresponding to the second audio sub-band and the gain corresponding to the first frequency point.

[0119] In some embodiments, the delay determination unit is configured to:

[0120] Obtaining a maximum gain value among the gain values ​​respectively corresponding to the multiple audio sub-bands;

[0121] For any one of the audio sub-bands, subtract the maximum gain value from the gain value corresponding to the audio sub-band to obtain a normalized gain value corresponding to the audio sub-band;

[0122] A delay time corresponding to the audio sub-band is obtained according to the center frequency of the audio sub-band and the normalized gain value.

[0123] In some embodiments, the delay determination unit is configured to:

[0124] Obtaining a period length of the audio sub-band according to a center frequency of the audio sub-band;

[0125] According to the linear mapping relationship between the normalized gain value and the number of delay cycles, the number of delay cycles corresponding to the normalized gain value is obtained;

[0126] The delay time corresponding to the audio sub-band is obtained according to the number of delay cycles corresponding to the normalized gain value and the cycle length of the audio sub-band.

[0127] In some embodiments, the sub-band synthesis module 550 is configured to:

[0128] Adding audio sampling values ​​at the same position in the delayed multiple audio sub-bands to obtain audio sub-signals corresponding to the multiple positions;

[0129] The output audio signal is obtained according to the audio sub-signals respectively corresponding to the multiple positions.

[0130] It should be noted that the device provided in the above embodiment, when implementing its functions, is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the content structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the device and method embodiments provided in the above embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0131] Please refer to Figure 6 , which shows a block diagram of a computer device 600 provided in one embodiment of the present application. The computer device 600 may be any electronic device with data calculation, processing and storage functions. The computer device 600 may be used to implement the audio equalization method provided in the above embodiment.

[0132] Typically, the computer device 600 includes a processor 601 and a memory 602 .

[0133] The processor 601 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 601 may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field Programmable Gate Array), and PLA (Programmable Logic Array). The processor 601 may also include a main processor and a coprocessor. The main processor is a processor for processing data in an awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in a standby state. In some embodiments, the processor 601 may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 601 may also include an AI processor, which is used to process computing operations related to machine learning.

[0134] The memory 602 may include one or more computer-readable storage media, which may be non-transitory. The memory 602 may also include a high-speed random access memory and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 602 is used to store a computer program, which is configured to be executed by one or more processors to implement the above-mentioned audio equalization method.

[0135] Those skilled in the art will understand that Figure 6 The structure shown in the figure does not constitute a limitation on the computer device 600, and the computer device 600 may include more or less components than those shown in the figure, or combine some components, or adopt a different arrangement of components.

[0136] In an exemplary embodiment, a computer-readable storage medium is also provided, in which a computer program is stored, and when the computer program is executed by a processor of a computer device, the above-mentioned audio equalization method is implemented. Optionally, the above-mentioned computer-readable storage medium can be a ROM (Read-Only Memory), a RAM (Random Access Memory), a CD-ROM (Compact Disc Read-Only Memory), a magnetic tape, a floppy disk, an optical data storage device, etc.

[0137] In an exemplary embodiment, a computer program product is also provided, the computer program product comprising a computer program, the computer program being stored in a computer-readable storage medium. A processor of a computer device reads the computer program from the computer-readable storage medium, and the processor executes the computer program, so that the computer device performs the above audio equalization method.

[0138] It should be understood that the "multiple" mentioned in this article refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. In addition, the step numbers described in this article only illustrate a possible execution sequence between the steps. In some other embodiments, the above steps may not be executed in the order of the numbers, such as two steps with different numbers are executed at the same time, or two steps with different numbers are executed in the opposite order to the diagram. The embodiments of the present application are not limited to this.

[0139] The above description is only an exemplary embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An audio equalization method, It is characterized in that The method comprises: Acquire an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter includes at least one frequency point to be adjusted and a gain corresponding to the at least one frequency point, wherein the gain is used to amplify the frequency of the frequency point; Filtering the input audio signal through a filter bank to obtain a plurality of audio sub-bands, wherein the filter bank includes a low-pass filter, a high-pass filter and at least one band-pass filter, wherein the at least one band-pass filter is a band-pass filter divided based on a critical band of a Bark scale; Obtaining delay times corresponding to the plurality of audio sub-bands according to the at least one frequency point and the gains corresponding to the at least one frequency point, wherein the delay times are time for unifying auditory perception of the audio sub-bands; Delaying the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands to obtain multiple delayed audio sub-bands; The delayed multiple audio sub-bands are synthesized to obtain an output audio signal.

2. The method according to claim 1, It is characterized in that The obtaining, according to the at least one frequency point and the gains respectively corresponding to the at least one frequency point, the delay times respectively corresponding to the multiple audio sub-bands comprises: Obtaining gain values ​​respectively corresponding to the multiple audio sub-bands according to the at least one frequency point and the gains respectively corresponding to the at least one frequency point; Delay times corresponding to the multiple audio sub-bands are obtained according to the gain values ​​corresponding to the multiple audio sub-bands respectively.

3. The method according to claim 2, It is characterized in that The obtaining, according to the at least one frequency point and the gains respectively corresponding to the at least one frequency point, the gain values ​​respectively corresponding to the multiple audio sub-bands comprises: For a first frequency point among the at least one frequency point, obtaining a first audio sub-band and a second audio sub-band from the multiple audio sub-bands, wherein a frequency of the first frequency point is greater than or equal to a center frequency of the first audio sub-band, and a frequency of the first frequency point is less than a center frequency of the second audio sub-band; obtaining, according to the center frequency of the first audio sub-band, the center frequency of the second audio sub-band, the frequency of the first frequency point, and the gain corresponding to the first frequency point, a sub-gain value of the first frequency point allocated to the first audio sub-band and a sub-gain value of the first frequency point allocated to the second audio sub-band; A gain value corresponding to the first audio sub-band is obtained according to the sub-gain values ​​respectively allocated to the first audio sub-band at the at least one frequency point, and a gain value corresponding to the second audio sub-band is obtained according to the sub-gain values ​​respectively allocated to the second audio sub-band at the at least one frequency point.

4. The method according to claim 3, It is characterized in that The obtaining, according to the center frequency of the first audio sub-band, the center frequency of the second audio sub-band, the frequency of the first frequency point, and the gain corresponding to the first frequency point, a sub-gain value of the first frequency point allocated to the first audio sub-band and a sub-gain value of the first frequency point allocated to the second audio sub-band, comprises: Obtaining, according to a center frequency of the first audio sub-band, a center frequency of the second audio sub-band, and a frequency of the first frequency point, a distance corresponding to the first audio sub-band and a distance corresponding to the second audio sub-band; obtaining a sub-gain value allocated to the first audio sub-band by the first frequency point according to the distance corresponding to the first audio sub-band and the gain corresponding to the first frequency point; A sub-gain value of the first frequency point allocated to the second audio sub-band is obtained according to the distance corresponding to the second audio sub-band and the gain corresponding to the first frequency point.

5. The method according to claim 2, It is characterized in that The obtaining, according to the gain values ​​respectively corresponding to the plurality of audio sub-bands, the delay times respectively corresponding to the plurality of audio sub-bands comprises: Obtaining a maximum gain value among the gain values ​​respectively corresponding to the multiple audio sub-bands; For any one of the audio sub-bands, subtract the maximum gain value from the gain value corresponding to the audio sub-band to obtain a normalized gain value corresponding to the audio sub-band; A delay time corresponding to the audio sub-band is obtained according to the center frequency of the audio sub-band and the normalized gain value.

6. The method according to claim 5, It is characterized in that The obtaining, according to the center frequency of the audio sub-band and the normalized gain value, a delay time corresponding to the audio sub-band includes: Obtaining a period length of the audio sub-band according to a center frequency of the audio sub-band; According to the linear mapping relationship between the normalized gain value and the number of delay cycles, the number of delay cycles corresponding to the normalized gain value is obtained; The delay time corresponding to the audio sub-band is obtained according to the number of delay cycles corresponding to the normalized gain value and the cycle length of the audio sub-band.

7. The method according to any one of claims 1 to 6, It is characterized in that The synthesizing the delayed multiple audio sub-bands to obtain an output audio signal includes: Adding audio sampling values ​​at the same position in the delayed multiple audio sub-bands to obtain audio sub-signals corresponding to the multiple positions; The output audio signal is obtained according to the audio sub-signals respectively corresponding to the multiple positions.

8. An audio equalizer, It is characterized in that The device comprises: A signal acquisition module, used to acquire an input audio signal and an equalization adjustment parameter, wherein the equalization adjustment parameter includes at least one frequency point to be adjusted and a gain corresponding to the at least one frequency point, wherein the gain is used to amplify the frequency of the frequency point; a signal filtering module, configured to filter the input audio signal through a filter bank to obtain a plurality of audio sub-bands, wherein the filter bank comprises a low-pass filter, a high-pass filter and at least one band-pass filter, wherein the at least one band-pass filter is a band-pass filter divided based on a critical frequency band of a Bark scale; a delay determination module, configured to obtain delay times corresponding to the plurality of audio sub-bands respectively according to the at least one frequency point and the gains respectively corresponding to the at least one frequency point, wherein the delay times are time for unifying auditory perception of the audio sub-bands; A delay processing module, configured to perform delay processing on the multiple audio sub-bands according to the delay times respectively corresponding to the multiple audio sub-bands, to obtain multiple delayed audio sub-bands; The sub-band synthesis module is used to synthesize the delayed multiple audio sub-bands to obtain an output audio signal.

9. A computer device, It is characterized in that The computer device comprises a processor and a memory, wherein a computer program is stored in the memory, and the computer program is loaded and executed by the processor to implement the audio equalization method according to any one of claims 1 to 7.

10. A computer-readable storage medium, It is characterized in that The computer-readable storage medium stores a computer program, which is loaded and executed by a processor to implement the audio equalization method according to any one of claims 1 to 7.

11. A computer program product, It is characterized in that The computer program product comprises a computer program, which is loaded and executed by a processor to implement the audio equalization method according to any one of claims 1 to 7.

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