Audio playback system sound effect calibration method, device, system and storage medium

Abstract

The present disclosure provides an audio effect calibration method, device, system and storage medium of an audio playing system; in the method, a test audio is played by controlling a subwoofer and a main sound box, a transmission audio at a main listening position is collected by using an audio collection device, a sound emission time delay and a volume parameter difference are analyzed, and the subwoofer is calibrated in combination with an audio response curve of a scene, so as to solve the problem that the precision of audio effect calibration between the subwoofer and the main sound box is low in the prior art, and the user's listening experience is low.

Description

Technical Field

[0001] This disclosure relates to the field of audio processing technology, and in particular to a method, apparatus, system and storage medium for calibrating the sound effects of an audio playback system. Background Technology

[0002] In modern home theaters and high-fidelity audio systems, the subwoofer, as a device specifically responsible for low-frequency reproduction, has a crucial impact on the overall sound quality. However, since subwoofers are usually installed separately from the main speakers, a balanced calibration of both is necessary.

[0003] In existing technologies, the balance calibration of subwoofers and main speakers is mainly achieved by calibrating the transmission time delay of audio signals between the two to achieve audio synchronization calibration. The balance of sound quality and volume is achieved through manual calibration. In other words, the current balance calibration method does not take into account factors such as the acoustic characteristics of the environment, resulting in inaccurate calibration. Summary of the Invention

[0004] In view of this, the purpose of this disclosure is to provide a sound effect calibration method, device, system and storage medium for an audio playback system, so as to solve the problem that the accuracy of sound effect calibration between the subwoofer and the main speaker in the prior art is low, resulting in a poor listening experience for users.

[0005] In a first aspect, embodiments of this disclosure provide a sound effect calibration method for an audio playback system. The audio playback system includes at least a subwoofer, a main speaker, and an audio acquisition device. The method includes: detecting the connection status of the subwoofer and the main speaker, and the working status of the audio acquisition device, and determining whether the connection status and the working status are normal; if normal, using a first test audio to test the acoustic characteristics of the scene where the audio playback system is located and the delay at the main listening position, obtaining the frequency response curve and transmission time delay of the scene, wherein the transmission time delay is the time difference between the transmission of the first test audio from the locations of the subwoofer and the main speaker to the main listening position; controlling the subwoofer and the main speaker to play a second test audio respectively, acquiring the transmission audio located at the main listening position through the audio acquisition device, and calculating the sound emission time delay between the subwoofer and the main speaker using a cross-correlation method; calculating the volume parameter difference of the subwoofer relative to the main speaker based on the transmission audio of the subwoofer and the transmission audio of the main speaker; and calibrating the device parameters of the subwoofer based on the sound emission time delay, the volume parameter difference, and the frequency response curve.

[0006] Optionally, the step of testing the acoustic characteristics of the scene where the audio playback system is located and the delay at the main listening position using the first test audio to obtain the frequency response curve and transmission time delay of the scene includes: playing the first test audio at the positions of the subwoofer and the main speaker respectively, and adjusting the audio acquisition device to the main listening position in the scene to use the test audio; calculating the time difference between the transmission of the first test audio from the positions of the subwoofer and the main speaker to the main listening position based on the reception time of the test audio and the transmission time of each of the first test audios, and obtaining the transmission time difference; analyzing the spectrum of the test audio and the first test audio using the Fast Fourier Transform algorithm, and calculating the corresponding frequency response based on the two analyzed spectra to obtain the frequency response curve of the scene.

[0007] Optionally, the step of controlling the subwoofer and the main speaker to play a second test audio, acquiring the transmitted audio at the main listening position through the audio acquisition device, and calculating the sound emission time delay between the subwoofer and the main speaker using a cross-correlation method includes: based on the second test audio, exciting the subwoofer to emit a first sound signal, and acquiring the first sound signal at the main listening position using the audio acquisition device; based on the second test audio, exciting the main speaker to emit a second sound signal, and acquiring the second sound signal at the main listening position using the audio acquisition device; and using the cross-correlation method to calculate the sound emission time delay between the subwoofer and the main speaker based on the time difference between the acquired first and second sound signals.

[0008] Optionally, calculating the volume parameter difference between the subwoofer and the main speaker based on the transmitted audio of the subwoofer and the transmitted audio of the main speaker includes: analyzing the sound pressure level data corresponding to the first sound signal and the second sound signal; determining whether the two sound pressure level data match; if they do not match, calculating the difference between the two sound pressure level data, and based on the difference, querying the configuration parameters of the subwoofer from a preset correspondence table of sound pressure and volume parameters; and calculating the volume parameter difference between the subwoofer and the main speaker based on the configuration parameters.

[0009] Optionally, calibrating the subwoofer's device parameters based on the sound emission time delay, the volume parameter difference, and the frequency response curve includes: determining whether the transmission time delay is greater than a preset delay threshold; compensating the subwoofer's sound emission time using the sound emission time delay or the transmission time delay and the sound emission time delay based on the determination result; calculating the subwoofer's compensated device parameters based on the volume parameter difference and the frequency response curve, and calibrating based on the compensated device parameters.

[0010] Optionally, the step of compensating the subwoofer's sound emission time using the sound emission time delay or the transmission time delay and the sound emission time delay based on the judgment result includes: determining whether the sound emission time delay is greater than zero; if the transmission time delay is greater than a preset delay threshold and the sound emission time delay is greater than zero, then delaying the subwoofer based on the transmission time delay and the sound emission time delay; if the transmission time delay is greater than a preset delay threshold and the sound emission time delay is less than zero, then advancing the subwoofer based on the transmission time delay and the sound emission time delay; if the transmission time delay is less than a preset delay threshold and the sound emission time delay is greater than zero, then delaying the subwoofer based on the sound emission time delay; if the transmission time delay is less than a preset delay threshold and the sound emission time delay is less than zero, then advancing the subwoofer based on the sound emission time delay.

[0011] Optionally, the step of compensating the subwoofer's emission time using the emission time delay or the transmission time delay and the emission time delay based on the judgment result further includes: analyzing the phase response of the main speaker and the subwoofer near the crossover point based on the transmission audio; calculating the difference between the phase response of the main speaker and the subwoofer; and delaying the subwoofer's emission time to a preset fine-tuning amplitude based on the difference, so as to achieve phase consistency between the subwoofer and the main speaker within the same frequency range.

[0012] Optionally, the step of calculating the compensation device parameters of the subwoofer based on the volume parameter difference and the frequency response curve, and calibrating based on the compensation device parameters, includes: calculating the audio gain value of the subwoofer using a binary method based on the volume parameter difference;

[0013] The frequency response curve and the transmitted audio of the subwoofer are fitted using the least squares method to obtain the actual frequency response of the subwoofer; based on the audio gain value and the actual frequency response, the compensation device parameters of the subwoofer are calculated and calibrated.

[0014] Optionally, after calibrating the subwoofer's device parameters based on the sound emission time delay, the volume parameter difference, and the frequency response curve, the method further includes: adjusting the audio acquisition device to transmit audio at multiple secondary listening positions in other locations, and calculating the corresponding sound emission time delay and volume parameter difference; using a weighted average method to fuse the sound emission time delay and volume parameter difference at each of the secondary listening positions to obtain a fusion compensation parameter, and calibrating the subwoofer.

[0015] Optionally, the step of using a weighted average method to fuse the differences in sound emission time delay and volume parameters at each of the secondary listening positions to obtain fusion compensation parameters, and calibrating the subwoofer, includes: measuring the distance between each of the secondary listening positions and the primary listening position, and assigning a corresponding weight value to each distance using a weighted average method; fusing the differences in sound emission time delay and volume parameters at each of the secondary listening positions based on the weight values ​​to obtain fusion compensation parameters, and calibrating the subwoofer.

[0016] Optionally, after measuring the distance between each of the secondary listening positions and the primary listening position, the method further includes: acquiring the frequency response curve of each of the secondary listening positions and calculating the standard deviation between each of the secondary listening positions and the primary listening position; and determining the spatial equalization of the scene based on each of the standard deviations.

[0017] Findably, assigning corresponding weight values ​​to each of the distances using a weighted average method includes: using a weighted average method to calculate the weight value of each of the secondary listening positions based on the spatial equalization and each of the distances.

[0018] Secondly, embodiments of this disclosure provide a sound effect calibration device for an audio playback system. The audio playback system includes at least a subwoofer, a main speaker, and an audio acquisition device. The device includes: a detection module, used to detect the connection status of the subwoofer and the main speaker, and the working status of the audio acquisition device, and to determine whether the connection status and the working status are normal; and a first testing module, used to test the acoustic characteristics of the scene where the audio playback system is located and the delay of the main listening position using a first test audio when the detection is normal, to obtain the frequency response curve and transmission time delay of the scene, wherein the transmission time delay is calculated by the first test audio. The second test module is used to control the subwoofer and the main speaker to play a second test audio, acquire the transmitted audio at the main listening position through the audio acquisition device, and calculate the sound emission time delay between the subwoofer and the main speaker using the cross-correlation method; the calculation module is used to calculate the volume parameter difference between the subwoofer and the main speaker based on the transmitted audio of the subwoofer and the transmitted audio of the main speaker; the calibration module is used to calibrate the device parameters of the subwoofer based on the sound emission time delay, the volume parameter difference, and the frequency response curve.

[0019] Thirdly, this disclosure provides an audio playback system, which includes at least a subwoofer, a main speaker, an audio acquisition device, a memory, and at least one processor. The memory stores instructions. The at least one processor invokes the instructions in the memory to cause the processor to execute the sound effect calibration method of the audio playback system described above.

[0020] Fourthly, embodiments of this disclosure provide a computer-readable storage medium storing computer-executable instructions. When the computer-executable instructions are invoked and executed by a processor, the computer-executable instructions cause the processor to implement the sound effect calibration method of the audio playback system described above.

[0021] The embodiments disclosed herein bring the following beneficial effects:

[0022] The aforementioned audio playback system's sound effect calibration method, apparatus, system, and storage medium detect the connection status of the subwoofer and the main speaker, as well as the operating status of the audio acquisition device, and determine whether the connection status and the operating status are normal. If normal, the system uses a first test audio to test the acoustic characteristics of the scene where the audio playback system is located and the delay at the main listening position, obtaining the frequency response curve and transmission time delay of the scene. The transmission time delay is the time difference between the transmission of the first test audio from the locations of the subwoofer and the main speaker to the main listening position. The system controls the subwoofer and the main speaker to play a second test audio, and the audio acquisition device acquires the transmission audio located at the main listening position. The system uses a cross-correlation method to calculate the sound emission time delay between the subwoofer and the main speaker. Based on the transmission audio of the subwoofer and the transmission audio of the main speaker, the system calculates the volume parameter difference between the subwoofer and the main speaker. The system calibrates the subwoofer's device parameters based on the sound emission time delay, the volume parameter difference, and the frequency response curve. By controlling the subwoofer and main speaker to play test audio, and using audio acquisition equipment to collect the transmitted audio at the main listening position, the differences in sound generation time delay and volume parameters are analyzed. Combined with the audio response curve of the scene, the subwoofer is calibrated, thereby solving the problem of low accuracy of sound effect calibration between the subwoofer and the main speaker in the existing technology, which leads to a poor listening experience for users.

[0023] Other features and advantages of this disclosure will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the disclosure. The objects and other advantages of this disclosure are realized and obtained through the structures particularly pointed out in the description, claims and drawings.

[0024] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a flowchart of one embodiment of the sound effect calibration method for an audio playback system in this disclosure;

[0027] Figure 2 This is a flowchart of another embodiment of the sound effect calibration method for the audio playback system in this disclosure;

[0028] Figure 3 This is a schematic diagram of one embodiment of the sound effect calibration device for the audio playback system in this disclosure;

[0029] Figure 4 This is a schematic diagram of one embodiment of the audio playback system in this disclosure. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0031] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in this disclosure, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” or “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0032] For ease of understanding, the specific process of the embodiments of this disclosure is described below. Please refer to [link / reference]. Figure 1 The embodiments of this disclosure are applied to an audio playback system that includes at least a subwoofer, a main speaker, and an audio acquisition device. One embodiment of the sound effect calibration method for the audio playback system in this disclosure includes:

[0033] Step S10: Detect the connection status of the subwoofer and main speaker, as well as the working status of the audio acquisition device, and determine whether the connection status and working status are normal.

[0034] It is understood that in this embodiment of the audio calibration method, the sound effect calibration method is triggered by the terminal. The terminal provides a graphical user interface, which displays trigger controls for sound acquisition commands and communication test commands. The user triggers the communication test command by operating the trigger controls. After the terminal responds to the command, it will detect the communication link between the subwoofer and the main speaker and send a test signal to test whether the audio acquisition device can acquire information.

[0035] Similarly, by operating the trigger control, a sound acquisition command can be triggered. The terminal responds to the sound acquisition command and starts playing at least one test signal while simultaneously acquiring ambient sound, thereby obtaining audio from different locations in the system's environment.

[0036] In this embodiment, the connection status of the subwoofer and the main speaker can be detected by signal voltage detection and audio signal detection. Specifically, the signal voltage detection method involves writing a program to periodically read the input port voltage of the subwoofer and the main speaker; setting a voltage threshold (e.g., 1V-10V); if the voltage is within this range and there is an audio signal output, the connection is considered normal.

[0037] For the audio signal detection method, an analog signal acquisition module is used to detect the frequency and intensity of the audio signal; if the signal frequency is within a preset range (such as 20Hz-20kHz), it is determined to be a normal connection.

[0038] The methods for detecting the working status of audio acquisition devices include input signal strength monitoring and frequency response detection. Specifically, the input signal strength monitoring method reads the input signal strength of the audio acquisition device through an ADC (analog-to-digital converter); a reasonable strength threshold is set to determine whether the input signal is within the normal range.

[0039] For the frequency response detection method, the FFT (Fast Fourier Transform) algorithm is used to analyze the frequency components of the input signal; ensure that the input signal is between 20Hz and 20kHz to determine whether the device is working properly.

[0040] Step S20: If normal, use the first test audio to test the acoustic characteristics of the scene where the audio playback system is located and the delay of the main listening position, and obtain the frequency response curve and transmission time delay of the scene.

[0041] It should be noted that the transmission time delay is the time difference between the transmission of the first test audio from the locations of the subwoofer and the main speaker to the main listening position. This step mainly performs a self-test on the subwoofer, main speaker, and audio acquisition device in the system to determine the audio response parameters before the hardware is tested, namely the frequency response curve and transmission time delay. The frequency response curve refers to the loss or delay curve of audio sound due to reflection and refraction in the current environment. This curve can provide a compensation basis for subsequent volume calibration and can be used to extract the acoustic characteristics of the current scene.

[0042] Specifically, a wideband test signal (such as a logarithmic sweep signal or an MLS sequence) is sent, and the room response is acquired through a measurement microphone. The acquired signal is analyzed using a Fast Fourier Transform (FFT) algorithm to obtain the room's frequency response curve. The audio acquisition device is placed at the main listening position, and the arrival time difference of sounds from different speakers is analyzed. Based on this arrival time difference, the listener's position relative to each speaker can be estimated; this arrival time difference is the transmission time delay between the sound source and the main listening position. The calculation of the transmission time delay can be achieved using a cross-correlation method.

[0043] Step S30: Control the subwoofer and main speaker to play the second test audio respectively, collect the transmitted audio located at the main listening position through the audio acquisition device, and calculate the sound emission time delay between the subwoofer and the main speaker using the cross-correlation method.

[0044] In one implementation, the subwoofer and main speaker are controlled to emit sound by triggering controls on the user interface to capture audio for an audio acquisition device (such as a microphone) located at the main listening position, and then the sound emission time delay is calculated using the cross-correlation method.

[0045] Specifically, the audio playback system excites the main speaker and subwoofer separately, and collects sound signals through a measuring microphone. The sound arrival time is calculated using a cross-correlation method.

[0046] R_ms(τ) = Σ[m(n)s(n+τ)]

[0047] τ_ms = argmax(R_ms(τ))

[0048] Where m(n) is the signal from the main speaker, s(n) is the signal from the subwoofer, and τ_ms is the time delay between the two.

[0049] It should be noted that the main listening position in step S30 differs from the main listening position in step S20 above. In step S30, the main listening position can be considered the surface or sound outlet of the subwoofer and main speaker enclosures. This sampling method ensures that the calculated signal processing delay is solely that of the device itself, excluding transmission delay.

[0050] In another embodiment, the subwoofer and main speaker can be tested sequentially or simultaneously in parallel. For sequential testing, the same second test audio can be used. For parallel testing, sound signals of different frequencies or frequency bands need to be constructed based on the second test audio and output to the subwoofer and main speaker for playback. Specifically, the time delay can also be calculated using a cross-correlation method.

[0051] Step S40: Calculate the volume parameter difference between the subwoofer and the main speaker based on the transmitted audio of the subwoofer and the transmitted audio of the main speaker.

[0052] It should be noted that the volume parameter difference refers to the sound pressure difference between the subwoofer and the main speaker. By analyzing the spectrum of the transmitted audio from the subwoofer and the main speaker respectively, the frequency and amplitude information is extracted. Based on the frequency and amplitude information, the corresponding sound pressure is calculated. Finally, the sound pressure difference between the subwoofer and the main speaker is calculated to obtain the volume parameter difference.

[0053] In this embodiment, the Fast Fourier Transform (FFT) algorithm can be used to analyze the spectrum of the transmitted audio to obtain the audio amplitude curves of the subwoofer and the main speaker. The standard deviation of the two curves is calculated to obtain the amplitude difference. Finally, the volume parameter difference is calculated using the relationship function between sound pressure, amplitude, and device parameters.

[0054] Step S50: Calibrate the subwoofer's device parameters based on sound emission time delay, volume parameter differences, and frequency response curves.

[0055] It should be noted that this calibration is divided into two independent steps: time delay calibration and volume calibration. Time delay calibration utilizes the occurrence time delay. If a transmission time delay exists, it also needs to be calibrated in conjunction with the transmission time delay. Specifically, the delay between the subwoofer and the main speaker is determined based on the occurrence time delay (e.g., the subwoofer before the main speaker or vice versa). The direction of time adjustment is determined based on this delay, and then time compensation is applied to the subwoofer in conjunction with the transmission time delay. This can be understood as adjusting the duration of the subwoofer's audio output or adjusting the triggering time. Regardless of the method, it essentially involves constructing the corresponding audio generation program, namely the subwoofer's sound production program.

[0056] The sound effect calibration method provided by the above embodiments controls the subwoofer and main speaker to play test audio, uses an audio acquisition device to collect the transmitted audio at the main listening position, analyzes the difference in sound start time delay and volume parameters, and calibrates the subwoofer in combination with the audio response curve of the scene. This solves the problem of low accuracy of sound effect calibration between the subwoofer and the main speaker in the prior art, which leads to a poor listening experience for users.

[0057] Please see Figure 2 Another embodiment of the audio effect calibration method for the audio playback system in this disclosure includes:

[0058] Step S201: Detect the connection status of the subwoofer and main speaker, as well as the working status of the audio acquisition device, and determine whether the connection status and working status are normal.

[0059] Step S202: If normal, use the first test audio to test the acoustic characteristics of the scene where the audio playback system is located and the delay of the main listening position, and obtain the frequency response curve and transmission time delay of the scene.

[0060] In one implementation, the system plays a first test audio at the positions of the subwoofer and the main speaker, respectively, and adjusts the audio acquisition device to the main listening position in the scene to use the test audio; based on the reception time of the test audio and the transmission time of each of the first test audios, the system calculates the time difference between the transmission of the first test audio from the positions of the subwoofer and the main speaker to the main listening position, respectively, to obtain the transmission time difference; the system uses a fast Fourier transform algorithm to analyze the spectrum of the test audio and the first test audio, and calculates the corresponding frequency response based on the two analyzed spectra to obtain the frequency response curve of the scene.

[0061] The frequency response can be calculated using the following formula:

[0062] H(f) = Y(f) / X(f),

[0063] Where Y(f) is the spectrum of the signal collected by the measuring microphone, and X(f) is the spectrum of the transmitted test signal.

[0064] Specifically, the Fast Fourier Transform algorithm is used to analyze the spectra of the test audio and the first test audio, and the corresponding frequency response is calculated based on the analyzed spectra to obtain the frequency response curve of the scene, including:

[0065] The test audio and the first test audio are denoised to remove background noise;

[0066] The denoised test audio and the first test audio are segmented to obtain multiple signal segments;

[0067] Perform a Fast Fourier Transform (FFT) on each signal segment to convert the time-domain signal into a frequency-domain signal, obtain the FFT results corresponding to the test audio and the first test audio, and extract the frequency and amplitude information therein;

[0068] Based on the extracted frequency and amplitude information, the frequency response curve of the scene is calculated, wherein the frequency response curve represents the relationship between amplitude response and frequency.

[0069] Understandably, this step is the initialization operation of each hardware component in the audio playback system. First, the connection status of the subwoofer and main speaker is initialized, and the working status of the audio acquisition device is initialized to ensure that it is in a normal state. If the initialization fails, the user needs to be prompted to troubleshoot. Otherwise, the relevant parameters of the acquisition environment on audio transmission are tested, such as the characteristics of audio refraction and reflection, and the transmission delay of audio at each location in the environment.

[0070] Specifically, the audio playback system sends a wideband test signal (such as a logarithmic sweep signal or an MLS sequence) and acquires the scene (i.e., the room) response through an audio acquisition device. The acquired signal is analyzed using a Fast Fourier Transform (FFT) algorithm to obtain the room's frequency response curve. This frequency response curve includes multiple frequency responses, and the calculation for each frequency response is performed using the formulas described above.

[0071] Furthermore, the audio playback system prompts the user to place the audio acquisition device in the primary listening position. By analyzing the arrival time difference (i.e., transmission time delay) of sound from different speakers, the audio playback system can estimate the listener's position relative to each speaker. The cross-correlation method can be used to calculate the transmission time delay, and its formula is as follows:

[0072] Rxy(τ)=Σ[x(n)y(n+τ)]

[0073] τ_max=argmax(Rxy(τ)),

[0074] Where x(n) and y(n) are test signals emitted from two different speakers, and τ_max is the time delay between the two signals.

[0075] Step S203: Based on the second test audio, the subwoofer is activated to emit a first sound signal, and the first sound signal located at the main listening position is acquired using an audio acquisition device.

[0076] Step S204: Based on the second test audio, excite the main speaker to emit a second sound signal, and use an audio acquisition device to acquire the second sound signal located at the main listening position.

[0077] Steps S203 and S204 involve parallel testing of the subwoofer and main speaker systems. For the main speaker, signal excitation is achieved by generating and sending a test signal (e.g., a pulse signal) to the main speaker via a signal generator, ensuring the generator's settings (frequency, amplitude) meet experimental requirements. For the subwoofer, signal excitation is also achieved by generating and sending a test signal to the subwoofer via a signal generator. This signal should be synchronized with the main speaker signal but with a different frequency range to cover the low-frequency range. Further, audio signals are recorded at the main listening position using audio acquisition equipment, i.e., separately acquiring the sound signals from the main speaker and subwoofer. The acquired signals are then denoised and mean-reduced to improve analysis accuracy. A window function is applied to the signals to reduce spectral leakage and boundary effects. Finally, cross-correlation analysis is performed on the sound signals from the main speaker and subwoofer, calculating their cross-correlation functions, and using these functions to calculate the sound emission time delay.

[0078] Step S205: Using the cross-correlation method, the time difference between the first and second sound signals is used to obtain the sound emission time delay between the subwoofer and the main speaker.

[0079] In one implementation, the first and second audio signals acquired are respectively subjected to noise reduction and mean removal processing;

[0080] Apply a window function to the processed signal;

[0081] The cross-correlation function of the signals is calculated, which includes performing Fourier transform on the first and second sound signals, calculating the cross-correlation function, and obtaining the cross-correlation function through inverse fast Fourier transform (IFFT).

[0082] The peak position is extracted from the cross-correlation function, and the arrival time difference between the two signals is calculated to obtain the sound emission time delay between the subwoofer and the main speaker.

[0083] Specifically, the cross-correlation calculation can be performed using the following steps:

[0084] Step 1: Perform Fourier transform on the signals from the main speaker and the subwoofer respectively to obtain their spectra.

[0085] Step 2: Calculate the cross-correlation function of the two signals. Cross-correlation is typically calculated using FFT, and the formula is:

[0086]

[0087] Where x(t) and y(t) are the signals from the main speaker and subwoofer, respectively, and τ is the time delay.

[0088] Step 3, use Fast Fourier Transform (FFT) to calculate the cross-correlation function:

[0089]

[0090] Where x(t) and y(t) are the signals of the main speaker and subwoofer, respectively, τ is the sound emission time delay, FFT is the fast Fourier transform, IFFT is the inverse fast Fourier transform, and ∗ represents complex conjugate.

[0091] Step S206: Analyze the sound pressure level data corresponding to the first sound signal and the second sound signal.

[0092] Step S207: Determine whether the two sound pressure level data match.

[0093] Step S208: If there is a mismatch, calculate the difference between the two sound pressure level data, and based on the difference, look up the subwoofer configuration parameters from the preset sound pressure and volume parameter correspondence table.

[0094] Step S209: Calculate the volume parameter difference between the subwoofer and the main speaker based on the configuration parameters.

[0095] In practical applications, when controlling the main speaker to emit a second sound signal, a reference sound pressure level (typically 85 dB SPL) is set for the second sound signal. The second sound signal is constructed using pink noise for testing, and its sound pressure level data is acquired using an audio acquisition device. Simultaneously, the sound pressure level data of the first sound signal is acquired in real time and then paired to determine the difference between the two.

[0096] Step S210: Perform delay calibration on the subwoofer's sound emission time based on the sound emission time delay.

[0097] In one embodiment, it is determined whether the transmission time delay is greater than a preset delay threshold; based on the determination result, the sound emission time of the subwoofer is compensated using the sound emission time delay or the transmission time delay and the sound emission time delay; based on the volume parameter difference and the frequency response curve, the compensation device parameters of the subwoofer are calculated, and calibration is performed based on the compensation device parameters.

[0098] The step of compensating the subwoofer's sound emission time based on the judgment result, using either the sound emission time delay or the transmission time delay and the sound emission time delay, includes:

[0099] Determine whether the sound emission time delay is greater than zero;

[0100] If the transmission time delay is greater than a preset delay threshold and the sound emission time delay is greater than zero, then the subwoofer is delayed based on the transmission time delay and the sound emission time delay.

[0101] If the transmission time delay is greater than a preset delay threshold and the sound emission time delay is less than zero, then the subwoofer is preprocessed based on the transmission time delay and the sound emission time delay.

[0102] If the transmission time delay is less than a preset delay threshold and the sound emission time delay is greater than zero, then the subwoofer is delayed based on the sound emission time delay.

[0103] If the transmission time delay is less than a preset delay threshold and the sound emission time delay is less than zero, then the subwoofer is preprocessed based on the sound emission time delay.

[0104] Furthermore, the step of compensating the subwoofer's sound emission time using the sound emission time delay or the transmission time delay and the sound emission time delay based on the judgment result further includes:

[0105] Based on the transmitted audio, the phase response of the main speaker and the subwoofer near the crossover point is analyzed;

[0106] The difference in phase response between the main speaker and the subwoofer is calculated, and the sound emission time of the subwoofer is delayed to a preset fine-tuning amplitude based on the difference, so as to achieve phase consistency between the subwoofer and the main speaker in the same frequency range.

[0107] Step S211: Calibrate the subwoofer's device parameters based on volume parameter differences and frequency response curves.

[0108] In one implementation, the audio gain value of the subwoofer is calculated using a binary method based on the difference in volume parameters.

[0109] The frequency response curve and the transmitted audio of the subwoofer are fitted using the least squares method to obtain the actual frequency response of the subwoofer.

[0110] Based on the audio gain value and the actual frequency response, the compensation device parameters of the subwoofer are calculated and calibrated.

[0111] It should be noted that volume calibration here can be understood as including the main speaker reference level device (i.e., setting the sound pressure level data of the second audio signal), subwoofer level matching, and frequency response curve smoothing, among which:

[0112] The main speaker reference level is set as follows: First, set the main speaker to a reference sound pressure level (typically 85 dB SPL). Test using a pink noise signal and collect sound pressure level data via a measuring microphone.

[0113] Subwoofer level matching involves gradually adjusting the subwoofer's gain until its sound pressure level near the crossover point matches that of the main speaker. A binary search method can be used to quickly find a suitable gain value; the formula is as follows:

[0114] gain_sub = binary_search(gain_min, gain_max, tolerance)

[0115] The binary_search function implements the binary search algorithm, where gain_min and gain_max are the gain search ranges, and tolerance is the allowed error range.

[0116] Frequency response curve smoothing is achieved by using parametric equalization (PEQ) to fine-tune the subwoofer's frequency response to make the low-frequency response smoother. The target curve can be fitted using the least squares method, and its calculation formula is as follows:

[0117] H_target(f) = a_0 + a_1f + a_2f^2 + ... + a_nf^n

[0118] [a_0, a_1, ..., a_n] = argmin(Σ[H_measured(f) - H_target(f)]^2)

[0119] Based on the fitting results, the audio playback system can automatically set the PEQ parameters to calculate the actual frequency response.

[0120] In another embodiment, after calibrating the subwoofer's device parameters based on the sound emission time delay, the volume parameter difference, and the frequency response curve, the method further includes:

[0121] The audio acquisition device is adjusted to transmit audio from multiple secondary listening positions in other locations, and the corresponding sound emission time delay and volume parameter differences are calculated; that is, a set of time delay and volume calibration data is obtained.

[0122] {(delay_1, gain_1), (delay_2, gain_2), ..., (delay_n, gain_n)}.

[0123] The differences in sound emission time delay and volume parameters at each of the secondary listening positions are fused using a weighted average method to obtain fusion compensation parameters, and the subwoofer is then calibrated.

[0124] Understandably, the system is situated in a space of a certain area, allowing users to listen from different positions. To ensure the calibrated system delivers the same sound effect from every location, a multi-point acquisition calibration method is employed. The implementation steps include:

[0125] Step 1: Place measurement microphones at different listening positions and measure the delay and gain of the subwoofer respectively. The measurement is performed with time delay and volume calibration steps at each position.

[0126] Step 2: Perform weighted averaging on the calibration data from different listening positions. The weights are set based on the distance between the secondary and primary listening positions to optimize the overall delay and gain settings of the subwoofer. The formula for calculating the weights is as follows:

[0127] delay_opt = Σ(w_i * delay_i) / Σw_i

[0128] gain_opt = Σ(w_i * gain_i) / Σw_i

[0129] Where w_i is the weight of the i-th listening position.

[0130] Step 3: Calculate the standard deviation of the frequency response curves at each measurement point, evaluate the spatial balance of the entire listening area, and optimize the sound distribution of the subwoofer.

[0131] Furthermore, the step of using a weighted average method to fuse the differences in sound emission time delay and volume parameters at each of the secondary listening positions to obtain fusion compensation parameters, and calibrating the subwoofer, includes:

[0132] The distance between each of the secondary listening positions and the primary listening position is measured, and a weighted average method is used to assign a corresponding weight value to each distance; based on each weight value, the differences in sound emission time delay and volume parameters of each of the secondary listening positions are fused to obtain fusion compensation parameters, and the subwoofer is calibrated.

[0133] After measuring the distance between each of the secondary listening positions and the primary listening position, the method further includes:

[0134] Obtain the frequency response curves of each of the secondary listening positions, and calculate the standard deviation between each of the secondary listening positions and the primary listening position; determine the spatial equalization of the scene based on each standard deviation; the calculation formula is: σ(f) = sqrt(Σ[H_i(f) - H_avg(f)]^2 / N)

[0135] Where H_i(f) is the frequency response of the i-th listening position, H_avg(f) is the average frequency response, and N is the number of listening positions.

[0136] The step of assigning corresponding weight values ​​to each distance using a weighted average method includes:

[0137] Using a weighted average method, the weight values ​​of each of the secondary listening positions are calculated based on the spatial equalization and each of the distances.

[0138] In practical applications, the scene set by the audio playback system changes over time, with the addition of new layouts, devices, and objects, which alters its impact on the audio, particularly the frequency response curve and transmission time delay. This can lead to desynchronization between the subwoofer and the main speaker. To address this, this embodiment provides an adaptive optimization calibration scheme, the adaptive optimization calibration steps of which include:

[0139] The system continuously monitors audio playback, including ambient noise levels, volume changes, and different types of audio content.

[0140] The monitoring data is used to train a machine learning model, which is used to predict the optimal subwoofer calibration parameters for different usage scenarios.

[0141] The system dynamically adjusts the subwoofer's latency and gain parameters based on the predictions of the machine learning model, enabling the subwoofer to adapt to different environmental changes and audio content, thus optimizing the user's listening experience. The machine learning model can be trained using collected data, such as a support vector machine (SVM) or a neural network, to predict the optimal calibration parameters under different conditions.

[0142] [delay_pred,gain_pred]=ML_model(audio_type,volume, noise_level, ...)

[0143] Furthermore, the scenario will also include multiple subwoofers and main speakers. Therefore, the calibration process further includes acquiring the volume parameter differences of each subwoofer for collaborative calibration. This multi-subwoofer collaborative calibration step includes:

[0144] In a multi-subwoofer system, the delay and gain parameters of each subwoofer are measured separately, taking into account the mutual influence between multiple subwoofers;

[0145] Based on the measurement results, the relative delay and gain settings of multiple subwoofers are optimized to ensure that the sound of all subwoofers blends consistently.

[0146] Automatic crossover point adjustment, which automatically selects the optimal crossover point by analyzing the frequency response curves of the main speaker and subwoofer.

[0147] Furthermore, the phase response adjustment of the crossover point can be set to automatic adjustment. Specifically, by testing the frequency response data of the main speaker and subwoofer, the frequency at which the low-frequency response of the main speaker begins to decay and the flat range of the low-frequency response of the subwoofer are determined. The optimal crossover point between the main speaker and the subwoofer is automatically determined. The determination of the crossover point is based on the superposition effect of the frequency responses, so that the low-frequency response is seamless. Its expression is:

[0148] f_crossover = find_optimal_crossover(H_main(f), H_sub(f))

[0149] The `find_optimal_crossover` function here implements a heuristic algorithm to find the frequency point where the low-frequency response of the main speaker begins to decay and the subwoofer response flattens.

[0150] In another embodiment, during calibration, it can be a range adjustment. Specifically, during the adaptive optimization described above, the dynamic range characteristics of the audio content of the subwoofer and main speaker are monitored. The dynamic range includes the difference between the minimum and maximum values ​​of the audio. The compression ratio and compression threshold of the subwoofer are automatically adjusted according to the dynamic range to avoid overload during high-volume playback and to ensure the stability and sound quality of the bass output.

[0151] Furthermore, after calibration, parameter optimization is also included based on user feedback on the user interface. Specifically, user ratings or adjustment opinions on the sound effects are collected through the user interface. The user feedback data is used to update the machine learning model, and the updated model further optimizes the calibration parameters of Subwoofer.

[0152] In another embodiment, to facilitate user calibration control, this disclosure also designs a user-friendly interface to guide users through the initial calibration process. The interface provides feedback on the microphone placement and calibration progress through animation or graphics. It provides a one-click automatic calibration function while retaining a manual adjustment function for advanced users to perform fine-tuning.

[0153] The user interface also includes a scene preset function, which includes:

[0154] It provides sound effect presets for different usage scenarios such as movies, music, and games, which users can quickly switch between;

[0155] The system automatically loads the corresponding Subwoofer calibration parameters based on the selected scenario.

[0156] In another embodiment, when the subwoofer, main speaker, and audio acquisition device are detected, the system's hardware and software are periodically self-tested to ensure that the subwoofer, main speaker, and other devices are working properly; a self-test report is generated, and if an abnormality is detected, the user is prompted to maintain or recalibrate.

[0157] During the calibration process, the system detects abnormalities in the frequency response curve or calibration parameters in real time; it automatically identifies abnormalities and issues warnings or automatically adjusts to restore the normal calibration state.

[0158] Furthermore, a firmware update mechanism is provided for the hardware support of the subwoofer and main speaker of the audio playback system. This firmware update mechanism includes the following steps:

[0159] Regularly check for new firmware versions, which include algorithm improvements and feature enhancements;

[0160] Prevent unexpected interruptions during system updates to ensure the system can continue to operate normally after the update.

[0161] The audio playback system sound effect calibration method provided by the above-described implementation method achieves comprehensive and accurate low-frequency optimization by combining time delay and volume calibration. The method first performs system initialization and environmental detection, comprehensively analyzing the room's acoustic characteristics and the listener's position. Subsequently, through precise time delay calculation and phase alignment optimization, perfect synchronization between the subwoofer and the main speaker is ensured. In the volume calibration stage, a binary method is used to quickly match levels, and parametric equalization is used to smooth the frequency response. Multi-point optimization technology fuses data from multiple locations using a weighted average method, significantly improving spatial equalization. Particularly noteworthy is the introduction of a machine learning-based adaptive optimization mechanism, which dynamically adjusts parameters according to different audio content and environmental noise, continuously optimizing the listening experience. Furthermore, this method includes advanced functions such as multiple subwoofer collaborative calibration and automatic crossover point adjustment, further enhancing the system's flexibility and adaptability. The user-friendly interface design and operation process simplify the complex calibration process while retaining the possibility of professional tuning. Finally, a robust anomaly detection and self-diagnosis mechanism ensures the long-term stability and reliability of the system. Overall, this comprehensive, intelligent, and adaptive calibration method not only overcomes the limitations of traditional technologies but also provides users with an unprecedented high-quality low-frequency experience, making it of significant application value in the fields of home theaters and high-fidelity audio systems.

[0162] The audio effect calibration method of the audio playback system in this disclosure has been described above. The audio effect calibration device of the audio playback system in this disclosure is described below. Please refer to [link / reference]. Figure 3 The audio playback system in this embodiment includes a sound effect calibration device, wherein the audio playback system includes at least a subwoofer, a main speaker, and an audio acquisition device, and the device includes:

[0163] The detection module 310 is used to detect the connection status of the subwoofer and the main speaker, as well as the working status of the audio acquisition device, and to determine whether the connection status and the working status are normal.

[0164] The first test module 320 is used to test the acoustic characteristics of the scene where the audio playback system is located and the delay of the main listening position using the first test audio when the detection is normal, so as to obtain the frequency response curve and transmission time delay of the scene, wherein the transmission time delay is the time difference between the transmission of the first test audio from the subwoofer and the main speaker to the main listening position respectively.

[0165] The second test module 330 is used to control the subwoofer and the main speaker to play the second test audio respectively, acquire the transmitted audio located at the main listening position through the audio acquisition device, and calculate the sound emission time delay between the subwoofer and the main speaker using the cross-correlation method;

[0166] The calculation module 340 is used to calculate the difference in volume parameters of the subwoofer relative to the main speaker based on the transmitted audio of the subwoofer and the transmitted audio of the main speaker.

[0167] The calibration module 350 is used to calibrate the device parameters of the subwoofer based on the sound emission time delay, the volume parameter difference, and the frequency response curve.

[0168] Optionally, the first test module 320 is specifically used for:

[0169] The first test audio is played at the positions of the subwoofer and the main speaker, respectively, and the audio acquisition device is adjusted to the main listening position in the scene to use the test audio.

[0170] Based on the reception time of the test audio and the transmission time of each of the first test audios, the time difference between the transmission of the first test audio from the location of the subwoofer and the main speaker to the main listening position is calculated, and the transmission time difference is obtained.

[0171] The frequency response curve of the scene is obtained by analyzing the spectrum of the test audio and the first test audio using the Fast Fourier Transform algorithm and calculating the corresponding frequency response based on the two analyzed spectra.

[0172] Optionally, the second test module 330 is specifically used for:

[0173] Based on the second test audio, the subwoofer is excited to emit a first sound signal, and the first sound signal located at the main listening position is acquired using the audio acquisition device;

[0174] Based on the second test audio, the main speaker is excited to emit a second sound signal, and the audio acquisition device is used to acquire the second sound signal located at the main listening position;

[0175] The sound emission time delay between the subwoofer and the main speaker is obtained by using the cross-correlation method to measure the time difference between the first and second sound signals.

[0176] Optionally, the computing module 340 is specifically used for:

[0177] Analyze the sound pressure level data corresponding to the first sound signal and the second sound signal;

[0178] Determine whether the two sound pressure level data points match;

[0179] If they do not match, the difference between the two sound pressure level data is calculated, and based on the difference, the configuration parameters of the subwoofer are retrieved from a preset correspondence table of sound pressure and volume parameters.

[0180] The volume parameter difference between the subwoofer and the main speaker is calculated based on the configuration parameters.

[0181] Optionally, the calibration module 350 is specifically used for:

[0182] Determine whether the transmission time delay is greater than a preset delay threshold;

[0183] Based on the judgment result, the sound emission time of the subwoofer is compensated by using the sound emission time delay or the transmission time delay and the sound emission time delay.

[0184] Based on the difference in volume parameters and the frequency response curve, the compensation device parameters of the subwoofer are calculated, and calibration is performed based on the compensation device parameters.

[0185] Optionally, the calibration module 350 is specifically used for:

[0186] Determine whether the sound emission time delay is greater than zero;

[0187] If the transmission time delay is greater than a preset delay threshold and the sound emission time delay is greater than zero, then the subwoofer is delayed based on the transmission time delay and the sound emission time delay.

[0188] If the transmission time delay is greater than a preset delay threshold and the sound emission time delay is less than zero, then the subwoofer is preprocessed based on the transmission time delay and the sound emission time delay.

[0189] If the transmission time delay is less than a preset delay threshold and the sound emission time delay is greater than zero, then the subwoofer is delayed based on the sound emission time delay.

[0190] If the transmission time delay is less than a preset delay threshold and the sound emission time delay is less than zero, then the subwoofer is preprocessed based on the sound emission time delay.

[0191] Optionally, the calibration module 350 is further configured to:

[0192] Based on the transmitted audio, the phase response of the main speaker and the subwoofer near the crossover point is analyzed;

[0193] The difference in phase response between the main speaker and the subwoofer is calculated, and the sound emission time of the subwoofer is delayed to a preset fine-tuning amplitude based on the difference, so as to achieve phase consistency between the subwoofer and the main speaker in the same frequency range.

[0194] Optionally, the calibration module 350 is specifically used for:

[0195] Based on the difference in volume parameters, the audio gain value of the subwoofer is calculated using the binary method;

[0196] The frequency response curve and the transmitted audio of the subwoofer are fitted using the least squares method to obtain the actual frequency response of the subwoofer.

[0197] Based on the audio gain value and the actual frequency response, the compensation device parameters of the subwoofer are calculated and calibrated.

[0198] Optionally, the sound calibration device further includes an optimization module 360, used for:

[0199] The audio acquisition device is adjusted to transmit audio at multiple secondary listening positions in other locations, and the corresponding sound emission time delay and volume parameter differences are calculated.

[0200] The differences in sound emission time delay and volume parameters at each of the secondary listening positions are fused using a weighted average method to obtain fusion compensation parameters, and the subwoofer is then calibrated.

[0201] Optionally, the optimization module 360 ​​is specifically used for:

[0202] The distance between each of the secondary listening positions and the primary listening position is measured, and a weighted average method is used to assign a corresponding weight value to each distance;

[0203] Based on the weight values, the differences in sound emission time delay and volume parameters at each of the secondary listening positions are fused to obtain fusion compensation parameters, and the subwoofer is calibrated.

[0204] Optionally, the optimization module 360 ​​is further configured to:

[0205] Obtain the frequency response curves of each of the secondary listening positions, and calculate the standard deviation between each of the secondary listening positions and the primary listening position;

[0206] The spatial balance of the scene is determined based on the standard deviations of each standard deviation.

[0207] Optionally, the optimization module 360 ​​is specifically used for:

[0208] Using a weighted average method, the weight values ​​of each of the secondary listening positions are calculated based on the spatial equalization and each of the distances.

[0209] By implementing the aforementioned device, the connection status of the subwoofer and the main speaker, as well as the working status of the audio acquisition device, are detected, and it is determined whether the connection status and the working status are normal. If normal, the acoustic characteristics of the scene where the audio playback system is located and the delay at the main listening position are tested using the first test audio, and the frequency response curve and transmission time delay of the scene are obtained, wherein the transmission time delay is the time difference between the transmission of the first test audio from the locations of the subwoofer and the main speaker to the main listening position. The subwoofer and the main speaker are controlled to play the second test audio, and the transmission audio located at the main listening position is acquired by the audio acquisition device, and the sound emission time delay between the subwoofer and the main speaker is calculated using the cross-correlation method. Based on the transmission audio of the subwoofer and the transmission audio of the main speaker, the volume parameter difference of the subwoofer relative to the main speaker is calculated. Based on the sound emission time delay, the volume parameter difference, and the frequency response curve, the device parameters of the subwoofer are calibrated. By controlling the subwoofer and main speaker to play test audio, and using audio acquisition equipment to collect the transmitted audio at the main listening position, the differences in sound generation time delay and volume parameters are analyzed. Combined with the audio response curve of the scene, the subwoofer is calibrated, thereby solving the problem of low accuracy of sound effect calibration between the subwoofer and the main speaker in the existing technology, which leads to a poor listening experience for users.

[0210] above Figure 3 The sound effect calibration device in this disclosure embodiment is described in detail from the perspective of modular functional entities. The audio playback system in this disclosure embodiment is described in detail from the perspective of hardware processing.

[0211] See Figure 4 As shown, the audio playback system includes a subwoofer, a main speaker, an audio acquisition device, a processor 400, and a memory 401. The memory 401 stores machine-executable instructions that can be executed by the processor 400. The processor 400 executes the machine-executable instructions to implement the aforementioned sound effect calibration method.

[0212] Furthermore, Figure 4 The audio playback system shown also includes a bus 402 and a communication interface 403. The processor 400, the communication interface 403 and the memory 401 are connected through the bus 402.

[0213] The memory 401 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 403 (which can be wired or wireless), such as the Internet, wide area network, local area network, metropolitan area network, etc. The bus 402 may be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 4 The symbol is represented by a single double-headed arrow, but this does not mean that there is only one bus or one type of bus.

[0214] The processor 400 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of the processor 400 or by instructions in software form. The processor 400 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this disclosure. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this disclosure can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 401. The processor 400 reads the information in memory 401 and, in conjunction with its hardware, completes the method steps of the aforementioned embodiment.

[0215] This disclosure also provides a computer-readable storage medium, which can be a non-volatile computer-readable storage medium or a volatile computer-readable storage medium, wherein the computer-readable storage medium stores instructions that, when executed on a computer, cause the computer to perform the steps of the audio effect calibration method of the audio playback system.

[0216] The audio playback system sound effect calibration method, apparatus, system, and storage medium computer program product provided in this disclosure include a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the methods described in the preceding method embodiments. For specific implementation details, please refer to the method embodiments, which will not be repeated here.

[0217] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system and apparatus described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0218] Furthermore, in the description of the embodiments of this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0219] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this disclosure, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this disclosure. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0220] In the description of this disclosure, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0221] Finally, it should be noted that the above embodiments are merely specific implementations of this disclosure, used to illustrate the technical solutions of this disclosure, and not to limit it. The protection scope of this disclosure is not limited thereto. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this disclosure. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure, and should all be covered within the protection scope of this disclosure. Therefore, the protection scope of this disclosure should be determined by the protection scope of the claims.

Claims

1. A method for calibrating the sound effects of an audio playback system, characterized in that, The audio playback system includes at least a subwoofer, a main speaker, and an audio acquisition device, and the method includes: The connection status of the subwoofer and the main speaker, as well as the working status of the audio acquisition device, are detected, and it is determined whether the connection status and the working status are normal. If normal, the acoustic characteristics of the scene where the audio playback system is located and the delay of the main listening position are tested using the first test audio, and the frequency response curve and transmission time delay of the scene are obtained, wherein the transmission time delay is the time difference between the transmission of the first test audio from the subwoofer and the main speaker to the main listening position. The subwoofer and the main speaker are controlled to play a second test audio. The audio acquisition device acquires the transmitted audio at the listening positions of the subwoofer and the main speaker after the second test audio is played. The cross-correlation method is used to perform cross-correlation analysis on the transmitted audio at the listening positions to obtain the cross-correlation function. The sound emission time delay between the subwoofer and the main speaker is calculated based on the cross-correlation function. Based on the transmitted audio of the subwoofer and the transmitted audio of the main speaker, the difference in volume parameters of the subwoofer relative to the main speaker is calculated; The subwoofer's device parameters are calibrated based on the sound emission time delay, the volume parameter difference, and the frequency response curve.

2. The sound effect calibration method for the audio playback system according to claim 1, characterized in that, The step of testing the acoustic characteristics of the scene where the audio playback system is located and the delay at the main listening position using the first test audio, to obtain the frequency response curve and transmission time delay of the scene, includes: The first test audio is played at the positions of the subwoofer and the main speaker, respectively, and the audio acquisition device is adjusted to the main listening position in the scene to use the test audio. Based on the reception time of the test audio and the transmission time of each of the first test audios, the time difference between the transmission of the first test audio from the location of the subwoofer and the main speaker to the main listening position is calculated, and the transmission time difference is obtained. The Fast Fourier Transform algorithm is used to perform spectral analysis on the test audio and the first test audio, and the corresponding frequency response is calculated based on the two analyzed spectra to obtain the frequency response curve of the scene.

3. The sound effect calibration method for the audio playback system according to claim 1, characterized in that, The subwoofer and the main speaker are respectively controlled to play the second test audio. The audio acquisition device acquires the transmitted audio at the listening position after the subwoofer and the main speaker play the second test audio. The cross-correlation method is used to perform cross-correlation analysis on the transmitted audio at the listening position to obtain the cross-correlation function. The sound emission time delay between the subwoofer and the main speaker is calculated based on the cross-correlation function, including: Based on the second test audio, the subwoofer is excited to emit a first sound signal, and the first sound signal located at the listening position is acquired using the audio acquisition device; Based on the second test audio, the main speaker is excited to emit a second sound signal, and the second sound signal located at the listening position is acquired using the audio acquisition device; The time difference between the first and second sound signals is calculated using the cross-correlation method to obtain the sound emission time delay between the subwoofer and the main speaker.

4. The sound effect calibration method for the audio playback system according to claim 3, characterized in that, The calculation of the volume parameter difference between the subwoofer and the main speaker based on the transmitted audio from the subwoofer and the main speaker includes: Analyze the sound pressure level data corresponding to the first sound signal and the second sound signal; Determine whether the two sound pressure level data points match; If they do not match, the difference between the two sound pressure level data is calculated, and based on the difference, the configuration parameters of the subwoofer are retrieved from a preset correspondence table of sound pressure and volume parameters. The volume parameter difference between the subwoofer and the main speaker is calculated based on the configuration parameters.

5. The sound effect calibration method for an audio playback system according to any one of claims 1-4, characterized in that, The device parameters for calibrating the subwoofer based on the sound emission time delay, the volume parameter difference, and the frequency response curve include: Determine whether the transmission time delay is greater than a preset delay threshold; Based on the judgment result, the sound emission time of the subwoofer is compensated by using the sound emission time delay or the transmission time delay and the sound emission time delay. Based on the difference in volume parameters and the frequency response curve, the compensation device parameters of the subwoofer are calculated, and calibration is performed based on the compensation device parameters.

6. The sound effect calibration method for an audio playback system according to claim 5, characterized in that, The step of compensating for the subwoofer's sound emission time using the sound emission time delay or the transmission time delay and the sound emission time delay, based on the judgment result, includes: Determine whether the sound emission time delay is greater than zero; If the transmission time delay is greater than a preset delay threshold and the sound emission time delay is greater than zero, then the subwoofer is delayed based on the transmission time delay and the sound emission time delay. If the transmission time delay is greater than a preset delay threshold and the sound emission time delay is less than zero, then the subwoofer is preprocessed based on the transmission time delay and the sound emission time delay. If the transmission time delay is less than a preset delay threshold and the sound emission time delay is greater than zero, then the subwoofer is delayed based on the sound emission time delay. If the transmission time delay is less than a preset delay threshold and the sound emission time delay is less than zero, then the subwoofer is preprocessed based on the sound emission time delay.

7. The sound effect calibration method for an audio playback system according to claim 5, characterized in that, The step of compensating the subwoofer's sound emission time using the sound emission time delay or the transmission time delay and the sound emission time delay based on the judgment result further includes: Based on the transmitted audio, the phase response of the main speaker and the subwoofer near the crossover point is analyzed; The difference in phase response between the main speaker and the subwoofer is calculated, and the sound emission time of the subwoofer is delayed to a preset fine-tuning amplitude based on the difference, so as to achieve phase consistency between the subwoofer and the main speaker in the same frequency range.

8. The sound effect calibration method for an audio playback system according to claim 5, characterized in that, The step of calculating the subwoofer's compensation device parameters based on the volume parameter difference and the frequency response curve, and calibrating based on the compensation device parameters, includes: Based on the difference in volume parameters, the audio gain value of the subwoofer is calculated using the binary method; The frequency response curve and the transmitted audio of the subwoofer are fitted using the least squares method to obtain the actual frequency response of the subwoofer. Based on the audio gain value and the actual frequency response, the compensation device parameters of the subwoofer are calculated and calibrated.

9. The sound effect calibration method for an audio playback system according to claim 1, characterized in that, After calibrating the subwoofer's device parameters based on the sound emission time delay, the volume parameter difference, and the frequency response curve, the method further includes: The audio acquisition device is adjusted to transmit audio at multiple secondary listening positions in other locations, and the corresponding sound emission time delay and volume parameter differences are calculated. The differences in sound emission time delay and volume parameters at each of the secondary listening positions are fused using a weighted average method to obtain fusion compensation parameters, and the subwoofer is then calibrated.

10. The sound effect calibration method for an audio playback system according to claim 9, characterized in that, The process of using a weighted average method to fuse the differences in sound emission time delay and volume parameters at each of the secondary listening positions to obtain fusion compensation parameters, and then calibrating the subwoofer, includes: The distance between each of the secondary listening positions and the primary listening position is measured, and a weighted average method is used to assign a corresponding weight value to each distance; Based on the weight values, the differences in sound emission time delay and volume parameters at each of the secondary listening positions are fused to obtain fusion compensation parameters, and the subwoofer is calibrated.

11. The sound effect calibration method for the audio playback system according to claim 10, characterized in that, After measuring the distance between each of the secondary listening positions and the primary listening position, the method further includes: Obtain the frequency response curves of each of the secondary listening positions, and calculate the standard deviation between each of the secondary listening positions and the primary listening position; The spatial balance of the scene is determined based on the standard deviations of each standard deviation.

12. The sound effect calibration method for an audio playback system according to claim 11, characterized in that, Assigning corresponding weight values ​​to each distance using a weighted average method includes: Using a weighted average method, the weight values ​​of each of the secondary listening positions are calculated based on the spatial equalization and each of the distances.

13. A sound effect calibration device for an audio playback system, characterized in that, The audio playback system includes at least a subwoofer, a main speaker, and an audio acquisition device, wherein the device includes: The detection module is used to detect the connection status of the subwoofer and the main speaker, as well as the working status of the audio acquisition device, and to determine whether the connection status and the working status are normal. The first test module is used to test the acoustic characteristics of the scene where the audio playback system is located and the delay of the main listening position using the first test audio when the detection is normal, so as to obtain the frequency response curve and transmission time delay of the scene, wherein the transmission time delay is the time difference between the transmission of the first test audio from the subwoofer and the main speaker to the main listening position respectively. The second test module is used to control the subwoofer and the main speaker to play the second test audio respectively. It acquires the transmitted audio at the listening position after the subwoofer and the main speaker play the second test audio through the audio acquisition device, and performs cross-correlation analysis on the transmitted audio at the listening position using the cross-correlation method to obtain the cross-correlation function. Based on the cross-correlation function, it calculates the sound emission time delay between the subwoofer and the main speaker. The calculation module is used to calculate the difference in volume parameters of the subwoofer relative to the main speaker based on the transmitted audio of the subwoofer and the transmitted audio of the main speaker. A calibration module is used to calibrate the device parameters of the subwoofer based on the sound emission time delay, the volume parameter difference, and the frequency response curve.

14. An audio playback system, characterized in that, The audio playback system includes at least a subwoofer, a main speaker, an audio acquisition device, a memory, and at least one processor, wherein the memory stores instructions. The at least one processor invokes the instructions in the memory to cause the processor to execute the sound effect calibration method of the audio playback system as described in any one of claims 1-12.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when invoked and executed by a processor, cause the processor to implement the sound effect calibration method of the audio playback system according to any one of claims 1-12.

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