A method and system for preventing howling of audio equipment

Abstract

The present invention is applicable to the field of audio processing technology, and in particular to an anti-howling method and system for audio equipment, the method comprising: constructing and setting an audio playback system; calling a preset test audio, independently controlling each audio playback device according to the test audio, constructing a three-dimensional coordinate system, determining the position of a feedback pickup and multiple groups of audio playback devices; obtaining the audio to be played, performing frequency division processing on the audio to be played, and playing local audio of different frequency bands through different audio playback devices; picking up sound through a feedback pickup to obtain feedback frequency division audio, positioning an input pickup, and feedback-adjusting the input pickup based on the feedback frequency division audio. The present invention constructs an audio playback system, so that frequency division playback is performed when the audio is played, and then dynamic audio synthesis is performed according to the real-time position of the input pickup, thereby actively suppressing the occurrence of howling and improving the user experience.

Description

Technical Field

[0001] The present invention belongs to the technical field of audio processing, and in particular relates to an anti-howling method and system for audio equipment. Background Art

[0002] Howling in audio equipment is a high-frequency, sharp sound, usually caused by acoustic feedback or incompatibility between devices. This often occurs in audio equipment such as sound systems, headphone amplifiers, or conference phones. When the input and output signals form a closed loop at a certain frequency, the howling occurs when the signal is continuously amplified. To avoid this phenomenon, you can adjust the position of the device, use anti-feedback tools, or lower the volume and gain settings.

[0003] Although existing audio equipment is equipped with technology to suppress howling, the effect is often difficult to meet the requirements. Once howling occurs, it will produce a harsh sound, affecting the user experience. Summary of the invention

[0004] The purpose of the present invention is to provide an anti-howling method for an audio device, aiming to solve the problem that although the existing audio device is equipped with a howling suppression technology, the effect is often difficult to meet the requirements. Once howling occurs, a harsh sound will be emitted, affecting the user experience.

[0005] The present invention is implemented as follows: a method for preventing howling of an audio device, the method comprising:

[0006] Constructing and setting an audio playback system, the audio playback system includes two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices, and the audio playback devices and input pickups are both equipped with built-in Bluetooth modules;

[0007] Retrieve the preset test audio, independently control each audio playback device according to the test audio, build a three-dimensional coordinate system, and determine the positions of the feedback pickup and multiple groups of audio playback devices;

[0008] Get the audio to be played, perform frequency division processing on the audio to be played based on the number of audio playback devices, and play local audio in different frequency bands through different audio playback devices;

[0009] The feedback pickup is used to pick up sound, and feedback frequency-divided audio is obtained to locate the input pickup. The input pickup is feedback-adjusted based on the feedback frequency-divided audio.

[0010] Preferably, the step of calling preset test audio, independently controlling each audio playback device according to the test audio, constructing a three-dimensional coordinate system, and determining the positions of the feedback pickup and the multiple groups of audio playback devices specifically includes:

[0011] Retrieve the preset test audio, import the test audio into each audio playback device, and play it in turn through the audio playback devices;

[0012] When the audio player is playing, the feedback pickup and the input pickup are used to synchronously pick up the sound, thereby obtaining multiple groups of picked-up audio;

[0013] A three-dimensional coordinate system is constructed to determine the coordinates of the feedback pickup and the input pickup, and the position of each audio playback device is determined based on the picked-up audio.

[0014] Preferably, the step of obtaining the audio to be played, performing frequency division processing on the audio to be played based on the number of audio playback devices, and playing local audio of different frequency bands through different audio playback devices specifically includes:

[0015] Get the audio to be played, count the number of audio playback devices and the frequency range of the audio to be played;

[0016] Dividing the frequency range according to the number of audio playback devices to obtain a plurality of local frequency band ranges, wherein the local frequency band ranges include an upper frequency limit and a lower frequency limit;

[0017] Different filters are set according to the local frequency band range, and the audio to be played is filtered through different filters to obtain local audio in different frequency bands, which is played through the audio playback device.

[0018] Preferably, the steps of picking up sound through a feedback pickup to obtain feedback frequency-divided audio, positioning the input pickup, and performing feedback adjustment on the input pickup based on the feedback frequency-divided audio specifically include:

[0019] Picking up sound through a feedback pickup to obtain feedback frequency-divided audio, filtering the feedback frequency-divided audio, and extracting independent frequency-divided audio;

[0020] During the working process, the audio player communicates with the Bluetooth module in the input pickup in real time to determine the position of the input pickup in the room;

[0021] According to the distance between the audio playback device and the input pickup, the independent frequency-divided audio is superimposed to obtain feedback suppression audio, and the sound recorded by the input pickup is suppressed by the feedback suppression audio.

[0022] Preferably, the step of superimposing the independently divided-frequency audios according to the distance between the audio playback device and the input pickup to obtain the feedback suppressed audio includes calculating the distance between the audio playback device and the input pickup, determining the playback time difference of each independently divided-frequency audio, and aligning the feedback suppressed audios corresponding to the audio playback devices based on the playback time difference to obtain the feedback suppressed audio.

[0023] Another object of the present invention is to provide an anti-howling system for an audio device, the system comprising:

[0024] A playback system construction module, used to construct and set up an audio playback system, wherein the audio playback system includes two groups of feedback pickups, one group of input pickups, and multiple groups of audio playback devices, wherein both the audio playback devices and the input pickups are equipped with a built-in Bluetooth module;

[0025] The device positioning module is used to call the preset test audio, independently control each audio playback device according to the test audio, build a three-dimensional coordinate system, and determine the position of the feedback pickup and multiple groups of audio playback devices;

[0026] The audio frequency division module is used to obtain the audio to be played, perform frequency division processing on the audio to be played based on the number of audio playback devices, and play local audio of different frequency bands through different audio playback devices;

[0027] The howling suppression module is used to pick up sound through a feedback pickup to obtain feedback frequency-divided audio, locate the input pickup, and perform feedback adjustment on the input pickup based on the feedback frequency-divided audio.

[0028] Preferably, the device positioning module includes:

[0029] The audio playback unit is used to call the preset test audio, import the test audio into each audio playback device, and play it in turn through the audio playback devices;

[0030] The device testing unit is used to synchronously pick up sound through the feedback pickup and the input pickup when the audio playback device is playing, so as to obtain multiple groups of picked-up audio;

[0031] The position recognition unit is used to construct a three-dimensional coordinate system, determine the coordinates of the feedback pickup and the input pickup, and determine the position of each audio playback device based on the picked-up audio.

[0032] Preferably, the audio frequency division module includes:

[0033] A device information acquisition unit, used to acquire the audio to be played, count the number of audio playback devices and the frequency range of the audio to be played;

[0034] A frequency range division unit, used for dividing the frequency range according to the number of audio playback devices to obtain a plurality of local frequency band ranges, wherein the local frequency band ranges include an upper frequency limit and a lower frequency limit;

[0035] The audio filter unit is used to set different filters according to the local frequency band range, filter the audio to be played through different filters, obtain local audio in different frequency bands, and play it through the audio playback device.

[0036] Preferably, the howling suppression module includes:

[0037] The audio extraction unit is used to pick up sound through a feedback pickup to obtain feedback frequency-divided audio, filter the feedback frequency-divided audio, and extract independent frequency-divided audio;

[0038] A Bluetooth positioning unit is used to determine the position of the input pickup in the room through real-time communication between the audio playback device and the Bluetooth module in the input pickup during operation;

[0039] The audio suppression unit is used to perform superposition processing on the independent frequency-divided audio according to the distance between the audio playback device and the input pickup to obtain feedback suppression audio, and suppress the sound recorded by the input pickup through the feedback suppression audio.

[0040] Preferably, the step of superimposing the independently divided-frequency audios according to the distance between the audio playback device and the input pickup to obtain the feedback suppressed audio includes calculating the distance between the audio playback device and the input pickup, determining the playback time difference of each independently divided-frequency audio, and aligning the feedback suppressed audios corresponding to the audio playback devices based on the playback time difference to obtain the feedback suppressed audio.

[0041] The present invention provides an anti-howling method for audio equipment. By constructing an audio playback system, frequency division playback is performed when the audio is played, and then dynamic audio synthesis is performed according to the real-time position of the input pickup, thereby actively suppressing the occurrence of howling and improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 A flowchart of an anti-howling method for an audio device provided by an embodiment of the present invention;

[0043] Figure 2 A flowchart of the steps of calling preset test audio, independently controlling each audio playback device according to the test audio, constructing a three-dimensional coordinate system, and determining the positions of feedback pickups and multiple groups of audio playback devices provided by an embodiment of the present invention;

[0044] Figure 3 A flowchart of the steps of obtaining audio to be played, performing frequency division processing on the audio to be played based on the number of audio playback devices, and playing local audio of different frequency bands through different audio playback devices provided in an embodiment of the present invention;

[0045] Figure 4 A flowchart of the steps of picking up sound through a feedback pickup, obtaining feedback frequency-divided audio, locating an input pickup, and performing feedback adjustment on the input pickup based on the feedback frequency-divided audio provided in an embodiment of the present invention;

[0046] Figure 5 An architecture diagram of an anti-howling system for an audio device provided by an embodiment of the present invention;

[0047] Figure 6 An architecture diagram of a device positioning module provided by an embodiment of the present invention;

[0048] Figure 7 An architecture diagram of an audio frequency division module provided in an embodiment of the present invention;

[0049] Figure 8 This is an architecture diagram of a howling suppression module provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0051] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first xx script may be referred to as a second xx script, and similarly, a second xx script may be referred to as a first xx script.

[0052] like Figure 1 FIG. 1 is a flowchart of an anti-howling method for an audio device provided by an embodiment of the present invention, the method comprising:

[0053] S100, constructing and setting an audio playback system, wherein the audio playback system includes two groups of feedback pickups, one group of input pickups, and multiple groups of audio playback devices, and the audio playback devices and the input pickups are both equipped with built-in Bluetooth modules.

[0054] In this step, an audio playback system is constructed and set up. The audio playback system is set up in a venue where audio needs to be played. The audio playback system includes two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices. The number of feedback pickups is at least two, and the number of audio playback devices is at least one. Multiple groups can be set up in a large venue. The audio playback device is equipped with a Bluetooth module. Through the Bluetooth module, the audio playback device and the input pickup can communicate with each other. When configuring the audio playback system, the audio playback device and the feedback pickup are set in a fixed position. In the subsequent use process, the position of the audio playback device and the feedback pickup is not changed. Before the input pickup is officially put into use, the position is kept fixed. When it is officially used, the input pickup can be moved in the playback venue, that is, before the configuration is completed, the input pickup is in a temporarily fixed state, and the two groups of feedback pickups and the input pickup are not colinear.

[0055] S200, calling a preset test audio, independently controlling each audio playback device according to the test audio, constructing a three-dimensional coordinate system, and determining the positions of the feedback pickup and the multiple groups of audio playback devices.

[0056] In this step, a preset test audio is retrieved. The audio playback system includes a control center, which is connected to two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices. The control center is used to control the audio playback devices to play and process the audio collected by the feedback pickups and the input pickups. After the positions of the feedback pickups and the input pickups are determined, the positions of the feedback pickups and the input pickups are manually measured to construct a three-dimensional coordinate system, and the positions of the feedback pickups and the input pickups are marked in the three-dimensional coordinate system. At this time, each audio playback device is started one by one to play the test audio, and the playback time of the test audio and the time when the test audio is received by the feedback pickups and the input pickups are recorded, so as to calculate the distance between each audio playback device and the feedback pickups and the input pickups according to the propagation speed of sound. The coordinates of each audio playback device in the three-dimensional coordinate system can be determined by three groups of distance values. After the test is completed, the position of the input pickup can be moved at will.

[0057] S300, obtaining audio to be played, performing frequency division processing on the audio to be played based on the number of audio playback devices, and playing local audio in different frequency bands through different audio playback devices.

[0058] In this step, the audio to be played is obtained, the spectrum analysis is performed on the audio to be played, and the audio to be played is filtered. Specifically, a bandpass filter, a low-pass filter, and a high-pass filter can be used for filtering. The audio to be played is separated according to different frequency bands to obtain local audio corresponding to different frequency bands. The local audio is allocated, and one or more local audios corresponding to each audio playback device are determined, and played through the audio playback device.

[0059] S400, picking up sound through a feedback pickup to obtain feedback frequency-divided audio, positioning an input pickup, and performing feedback adjustment on the input pickup based on the feedback frequency-divided audio.

[0060] In this step, the feedback pickup is used to pick up the sound. After the audio played by the audio player is transmitted through the air, it will reach each pickup (including the feedback pickup and the input pickup) in turn. Without processing, the audio to be played will be amplified by the audio player and will enter the input pickup again, and the cycle will be repeated to form a closed-loop amplification path, which will cause howling. In the present invention, the feedback pickup is used to pick up the sound, so as to collect audio of multiple frequency bands and obtain feedback frequency-divided audio. The feedback frequency-divided audio corresponds to the local audio. The feedback frequency-divided audio The frequency is the sound of local audio played by the audio playback device. The input microphone receives the voice of the speaker on the one hand, and on the other hand, it also receives the sound from the audio playback device. Therefore, the two will overlap and be transmitted to the audio playback device again, thereby generating howling. In the present invention, the feedback microphone collects the feedback frequency-divided audio and inputs it into the input microphone, and performs alignment processing. The feedback frequency-divided audio is used to suppress the sound recorded by the input microphone, and the influence of the feedback frequency-divided audio on the input microphone is offset by generating a sound wave with an opposite phase, thereby avoiding the generation of howling.

[0061] like Figure 2 As shown, as a preferred embodiment of the present invention, the steps of calling preset test audio, independently controlling each audio playback device according to the test audio, constructing a three-dimensional coordinate system, and determining the positions of the feedback pickup and the multiple groups of audio playback devices specifically include:

[0062] S201, retrieve preset test audio, import the test audio into each audio playback device, and play it in turn through the audio playback devices.

[0063] In this step, a preset test audio is retrieved. The test audio may be an audio file of a preset frequency. When the audio player is playing the audio file, the time when the audio player plays the audio file is recorded and transmitted to the control center.

[0064] S202, when the audio player is playing, the feedback pickup and the input pickup are used to synchronously pick up sound to obtain multiple groups of picked-up audio.

[0065] In this step, when the audio playback device is playing, the feedback pickup and the input pickup are turned on synchronously, so the sound played by the audio playback device will reach the feedback pickup and the input pickup at different times to obtain picked-up audio. The feedback pickup and the input pickup both record the arrival time of each picked-up audio and send it to the control center.

[0066] S203, constructing a three-dimensional coordinate system, determining the coordinates of the feedback pickup and the input pickup, and determining the position of each audio playback device according to the picked-up audio.

[0067] In this step, a three-dimensional coordinate system is constructed. Since the coordinates of the feedback pickup and the input pickup have been determined, three coordinate points have been determined in the three-dimensional coordinate system, and the three coordinate points are not collinear. When the audio playback device plays sound, the sound emission time and the sound reception time have been determined. Based on the speed of sound propagation in the air, the distance value between the audio playback device and each pickup can be calculated. The coordinates of the three coordinate points and the distances between the coordinate points and the coordinate points to be determined are known, and the coordinates of the audio playback device in the three-dimensional coordinate system can be determined.

[0068] like Figure 3 As shown, as a preferred embodiment of the present invention, the step of obtaining the audio to be played, performing frequency division processing on the audio to be played based on the number of audio playback devices, and playing local audio of different frequency bands through different audio playback devices specifically includes:

[0069] S301, obtaining audio to be played, and counting the number of audio playing devices and the frequency range of the audio to be played.

[0070] In this step, the audio to be played is obtained. Different audio playback devices are suitable for playing audio of different frequencies. Larger playback units are suitable for processing low-frequency signals, while smaller playback units are suitable for processing high-frequency signals. The upper and lower limits of the frequency of the audio to be played are identified.

[0071] S302: Divide the frequency range according to the number of audio playback devices to obtain a plurality of local frequency band ranges, wherein the local frequency band range includes an upper frequency limit and a lower frequency limit.

[0072] In this step, the frequency range is divided according to the number of audio playback devices. The number of audio playback devices is counted as N, and the interval value of the frequency range is P. Then the entire frequency range will be divided into M intervals, where M is an integer multiple of N, such as M=2N, then one audio playback device corresponds to two local frequency band ranges.

[0073] S303, setting different filters according to the local frequency band range, filtering the audio to be played through different filters, obtaining local audio in different frequency bands, and playing through an audio playback device.

[0074] In this step, different filters are set according to the local frequency band range. By constructing the filter, the audio to be played is filtered to obtain the local audio corresponding to each local frequency band range, and played through the audio playback device. When playing, multiple local audios belonging to the same audio playback device are collectively referred to as a whole and played through the corresponding audio playback device.

[0075] like Figure 4 As shown, as a preferred embodiment of the present invention, the steps of picking up sound through a feedback pickup to obtain feedback frequency-divided audio, positioning the input pickup, and performing feedback adjustment on the input pickup based on the feedback frequency-divided audio specifically include:

[0076] S401, picking up sound through a feedback pickup to obtain feedback frequency-divided audio, filtering the feedback frequency-divided audio, and extracting independent frequency-divided audio.

[0077] In this step, sound is picked up by the feedback pickup. At this time, multiple audio playback devices will work synchronously. The distances between the audio playback devices and the feedback pickups are different. Then, during the playback process, the sound emitted by the audio playback devices will first reach different feedback pickups. A filter is provided in the feedback pickup. Each feedback pickup corresponds to multiple audio playback devices. The feedback frequency-divided audio is filtered by the filter to obtain the local audio played by the corresponding audio playback device. For example, the frequency range of the audio to be played is divided into 10 intervals, namely A1, A2..., A10, and there are two audio playback devices, namely B1 and B2 and B1 are used to play audio in five frequency bands, namely A1, A3, A5, A7 and A9; B2 is used to play audio in five frequency bands, namely A2, A4, A6, A8 and A10; the feedback pickups are C1 and C2 respectively, wherein C1 corresponds to B1 and C2 corresponds to B2. Then the feedback pickup C1 filters the feedback frequency-divided audio according to the five frequency bands, namely A1, A3, A5, A7 and A9, thereby obtaining independent frequency-divided audio in the five frequency bands, namely a1, a3, a5, a7 and a9. Similarly, filtering is performed through the feedback pickup C2 to obtain independent frequency-divided audio in the five frequency bands, namely a2, a4, a6, a8 and a10.

[0078] S402, during the working process, the audio player communicates with the Bluetooth module in the input pickup in real time to determine the position of the input pickup in the room.

[0079] In this step, during the working process, real-time communication is performed through the Bluetooth module in the audio playback device and the input pickup. Since both the audio playback device and the input pickup are equipped with built-in Bluetooth modules, Bluetooth communication is continuously performed between the input pickup and the audio playback device, and the Bluetooth signal strength between the input pickup and the audio playback device is recorded. The distance between the two is calculated based on the Bluetooth signal strength, and then the position of the input pickup in the room can be determined based on the calculated multiple distances, thereby determining the real-time position of the input pickup.

[0080] S403, performing superposition processing on the independent frequency-divided audio according to the distance between the audio playback device and the input microphone to obtain feedback suppression audio, and suppressing the sound recorded by the input microphone through the feedback suppression audio.

[0081] In this step, the distance between the audio player and the input pickup is calculated. Since the sources of each independent frequency-divided audio are different, the time when each independent frequency-divided audio is transmitted to the input pickup is different, and there is a certain time difference. If the independent frequency-divided audio is directly synthesized in real time, the independent frequency-divided audio will be out of sync with the audio played by the audio player detected by the input pickup. Then, the howling suppression is performed based on the feedback suppression audio obtained by synthesizing the above independent frequency-divided audio. Due to the phase difference, the suppression effect is not ideal. In the present invention, the distance between the audio player and the input pickup is first calculated, and the playback time difference of each independent frequency-divided audio is determined. Based on the playback time difference, the feedback suppression audio corresponding to the audio player is aligned to obtain the feedback suppression audio, and then a sound wave signal with an anti-phase is generated according to the feedback suppression audio, thereby offsetting the sound played by the audio player detected by the input pickup, thereby achieving the effect of suppressing howling.

[0082] like Figure 5 As shown, an anti-howling system for an audio device provided by an embodiment of the present invention includes:

[0083] The playback system construction module 100 is used to construct and set up an audio playback system, which includes two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices. The audio playback devices and input pickups are both equipped with built-in Bluetooth modules.

[0084] In this system, the playback system construction module 100 constructs and sets up an audio playback system, and the audio playback system is set up in a venue where audio needs to be played. The audio playback system includes two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices. The number of feedback pickups is at least two, and the number of audio playback devices is at least one. Multiple groups can be set up in a large venue, wherein the audio playback device is equipped with a Bluetooth module, through which the audio playback device and the input pickup can communicate with each other. When configuring the audio playback system, the audio playback device and the feedback pickup are set in a fixed position. In the subsequent use process, the position of the audio playback device and the feedback pickup is not changed, and the input pickup is kept fixed before it is officially put into use. When it is officially used, the input pickup can be moved in the playback venue, that is, before the configuration is completed, the input pickup is in a temporarily fixed state, and the two groups of feedback pickups and the input pickup are not colinear.

[0085] The device positioning module 200 is used to retrieve preset test audio, independently control each audio playback device according to the test audio, construct a three-dimensional coordinate system, and determine the positions of feedback pickups and multiple groups of audio playback devices.

[0086] In this system, the device positioning module 200 retrieves the preset test audio, and the audio playback system includes a control center, which is connected to two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices. The control center is used to control the audio playback device to play and process the audio collected by the feedback pickup and the input pickup. After the positions of the feedback pickup and the input pickup are determined, the positions of the feedback pickup and the input pickup are manually measured to construct a three-dimensional coordinate system, and the positions of the feedback pickup and the input pickup are marked in the three-dimensional coordinate system. At this time, each audio playback device is started one by one to play the test audio, and the playback time of the test audio and the time when the test audio is received by the feedback pickup and the input pickup are recorded, so as to calculate the distance between each audio playback device and the feedback pickup and the input pickup according to the propagation speed of sound. The coordinates of each audio playback device in the three-dimensional coordinate system can be determined by three groups of distance values. After the test is completed, the position of the input pickup can be moved at will.

[0087] The audio frequency division module 300 is used to obtain the audio to be played, perform frequency division processing on the audio to be played based on the number of audio playback devices, and play local audio of different frequency bands through different audio playback devices.

[0088] In this system, the audio frequency division module 300 obtains the audio to be played, performs spectrum analysis on the audio to be played, and performs filtering processing on the audio to be played. Specifically, a bandpass filter, a low-pass filter, and a high-pass filter can be used for filtering processing to separate the audio to be played according to different frequency bands, thereby obtaining local audio corresponding to different frequency bands, allocating the local audio, determining one or more local audio corresponding to each audio playback device, and playing them through the audio playback device.

[0089] The howling suppression module 400 is used to pick up sound through a feedback pickup to obtain feedback frequency-divided audio, locate the input pickup, and perform feedback adjustment on the input pickup based on the feedback frequency-divided audio.

[0090] In this system, the howling suppression module 400 picks up sound through the feedback pickup. After the audio played by the audio playback device is transmitted through the air, it will reach each pickup (including the feedback pickup and the input pickup) in turn. Without processing, the audio to be played will be amplified by the audio playback device and then enter the input pickup again, and the cycle will be repeated to form a closed-loop amplification path, thereby causing howling. In the present invention, the feedback pickup is used to pick up sound, so as to collect audio of multiple frequency bands and obtain feedback frequency-divided audio. The feedback frequency-divided audio corresponds to the local audio. Feedback frequency-divided audio is the sound of local audio played through an audio playback device. The input microphone receives the voice of the speaker on the one hand, and on the other hand, it also receives the sound from the audio playback device. Therefore, the two will overlap and be transmitted to the audio playback device again, thereby generating howling. In the present invention, the feedback microphone collects the feedback frequency-divided audio and inputs it into the input microphone, and performs alignment processing. The feedback frequency-divided audio is used to suppress the sound recorded by the input microphone, and the influence of the feedback frequency-divided audio on the input microphone is offset by generating a sound wave with an opposite phase, thereby avoiding the generation of howling.

[0091] like Figure 6 As shown, as a preferred embodiment of the present invention, the device positioning module 200 includes:

[0092] The audio playing unit 201 is used to call the preset test audio, import the test audio into each audio playing device, and play it in turn through the audio playing devices.

[0093] In this module, the audio playback unit 201 retrieves a preset test audio, which may be an audio file of a preset frequency. When the audio playback device plays the audio file, the time when the audio playback device plays the audio file is recorded and the time is transmitted to the control center.

[0094] The device testing unit 202 is used to synchronously pick up sounds through the feedback pickup and the input pickup when the audio playing device is playing, so as to obtain multiple groups of picked-up audio.

[0095] In this module, when the device testing unit 202 plays the audio playback device, the feedback pickup and the input pickup are both turned on synchronously, so the sound played by the audio playback device will reach the feedback pickup and the input pickup at different times to obtain the picked-up audio. The feedback pickup and the input pickup both record the arrival time of each picked-up audio and send it to the control center.

[0096] The position identification unit 203 is used to construct a three-dimensional coordinate system, determine the coordinates of the feedback pickup and the input pickup, and determine the position of each audio playback device according to the picked-up audio.

[0097] In this module, the position identification unit 203 constructs a three-dimensional coordinate system. Since the coordinates of the feedback pickup and the input pickup have been determined, three coordinate points have been determined in the three-dimensional coordinate system, and the three coordinate points are not collinear. When the audio playback device plays sound, the sound emission time and the sound reception time have been determined. Based on the speed of sound propagation in the air, the distance value between the audio playback device and each pickup can be calculated. The coordinates of the three coordinate points and the distances between the coordinate points and the coordinate points to be determined are known, and the coordinates of the audio playback device in the three-dimensional coordinate system can be determined.

[0098] like Figure 7 As shown, as a preferred embodiment of the present invention, the audio frequency division module 300 includes:

[0099] The device information acquisition unit 301 is used to acquire the audio to be played, and count the number of audio playback devices and the frequency range of the audio to be played.

[0100] In this module, the device information acquisition unit 301 acquires the audio to be played. Different audio playback devices are suitable for playing audio of different frequencies. Larger playback units are suitable for processing low-frequency signals, while smaller playback units are suitable for processing high-frequency signals. The upper and lower limits of the frequency of the audio to be played are identified.

[0101] The frequency range division unit 302 is used to divide the frequency range according to the number of audio playback devices to obtain a plurality of local frequency band ranges, wherein the local frequency band range includes an upper frequency limit and a lower frequency limit.

[0102] In this module, the frequency range division unit 302 divides the frequency range according to the number of audio playback devices, counts the number of audio playback devices N, and the interval value of the frequency range is P, then the entire frequency range will be divided into M intervals, M is an integer multiple of N, such as M=2N, then one audio playback device corresponds to two local frequency band ranges.

[0103] The audio filtering unit 303 is used to set different filters according to the local frequency band range, filter the audio to be played through different filters, obtain local audio in different frequency bands, and play it through the audio playback device.

[0104] In this module, the audio filtering unit 303 sets different filters according to the local frequency band range, and filters the audio to be played by constructing filters to obtain local audio corresponding to each local frequency band range, which is played through the audio playback device. When playing, multiple local audios belonging to the same audio playback device are collectively referred to as a whole and played through the corresponding audio playback device.

[0105] like Figure 8 As shown, as a preferred embodiment of the present invention, the howling suppression module 400 includes:

[0106] The audio extraction unit 401 is used to pick up sound through a feedback microphone to obtain feedback frequency-divided audio, filter the feedback frequency-divided audio, and extract independent frequency-divided audio.

[0107] In this module, the audio extraction unit 401 picks up sound through the feedback pickup. At this time, multiple audio playback devices will work synchronously. The distances between the audio playback devices and the feedback pickups are different. Then, during the playback process, the sound emitted by the audio playback device will first reach different feedback pickups. A filter is provided in the feedback pickup. Each feedback pickup corresponds to multiple audio playback devices. The feedback frequency-divided audio is filtered by the filter to obtain the local audio played by the corresponding audio playback device. For example, the frequency range of the audio to be played is divided into 10 intervals, namely A1, A2..., A10, and there are two audio playback devices. They are B1 and B2, B1 is used to play audio in five frequency bands such as A1, A3, A5, A7 and A9, B2 is used to play audio in five frequency bands such as A2, A4, A6, A8 and A10, the feedback pickups are C1 and C2 respectively, among which C1 corresponds to B1, and C2 corresponds to B2, then the feedback pickup C1 filters the feedback frequency-divided audio according to the five frequency bands of A1, A3, A5, A7 and A9, thereby obtaining independent frequency-divided audio in five frequency bands such as a1, a3, a5, a7 and a9. Similarly, filtering is performed through the feedback pickup C2 to obtain independent frequency-divided audio in five frequency bands such as a2, a4, a6, a8 and a10.

[0108] The Bluetooth positioning unit 402 is used to determine the position of the input pickup in the room through real-time communication between the audio playback device and the Bluetooth module in the input pickup during operation.

[0109] In this module, during operation, the Bluetooth positioning unit 402 performs real-time communication through the Bluetooth module in the audio playback device and the input pickup. Since both the audio playback device and the input pickup are equipped with built-in Bluetooth modules, the input pickup and the audio playback device continuously perform Bluetooth communication, record the Bluetooth signal strength between the input pickup and the audio playback device, and calculate the distance between the two based on the Bluetooth signal strength. Then, the position of the input pickup in the room can be determined based on the calculated multiple distances, thereby determining the real-time position of the input pickup.

[0110] The audio suppression unit 403 is used to perform superposition processing on the independent frequency-divided audio according to the distance between the audio playback device and the input microphone to obtain feedback-suppressed audio, and suppress the sound recorded by the input microphone through the feedback-suppressed audio.

[0111] In this module, the audio suppression unit 403 calculates the distance between the audio playback device and the input pickup. Since the sources of each independent frequency-divided audio are different, the time when each independent frequency-divided audio is transmitted to the input pickup is different, and there is a certain time difference. If the independent frequency-divided audio is directly synthesized in real time, the independent frequency-divided audio will be out of sync with the audio played by the audio playback device detected by the input pickup. Then, the feedback suppression audio obtained by synthesizing the above independent frequency-divided audio is used to suppress howling, but the suppression effect is not ideal due to the phase difference. In the present invention, the distance between the audio playback device and the input pickup is first calculated, and the playback time difference of each independent frequency-divided audio is determined. Based on the playback time difference, the feedback suppression audio corresponding to the audio playback device is aligned to obtain the feedback suppression audio, and then a sound wave signal with an anti-phase is generated according to the feedback suppression audio, thereby offsetting the sound played by the audio playback device detected by the input pickup, thereby achieving the effect of suppressing howling.

[0112] It should be understood that, although each step in the flow chart of each embodiment of the present invention is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0113] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0114] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

[0116] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preventing howling in an audio device, characterized in that: The method comprises: Constructing and setting an audio playback system, the audio playback system includes two groups of feedback pickups, one group of input pickups and multiple groups of audio playback devices, and the audio playback devices and input pickups are both equipped with built-in Bluetooth modules; Retrieve the preset test audio, independently control each audio playback device according to the test audio, build a three-dimensional coordinate system, and determine the positions of the feedback pickup and multiple groups of audio playback devices; Get the audio to be played, perform frequency division processing on the audio to be played based on the number of audio playback devices, and play local audio in different frequency bands through different audio playback devices; Picking up sound through the feedback pickup to obtain feedback frequency-divided audio, positioning the input pickup, and performing feedback adjustment on the input pickup based on the feedback frequency-divided audio; The steps of calling preset test audio, independently controlling each audio playback device according to the test audio, constructing a three-dimensional coordinate system, and determining the positions of the feedback pickup and the multiple groups of audio playback devices specifically include: Retrieve the preset test audio, import the test audio into each audio playback device, and play it in turn through the audio playback devices; When the audio player is playing, the feedback pickup and the input pickup are used to synchronously pick up the sound, thereby obtaining multiple groups of picked-up audio; Construct a three-dimensional coordinate system, determine the coordinates of the feedback pickup and the input pickup, and determine the position of each audio playback device based on the picked-up audio; The step of obtaining the audio to be played, performing frequency division processing on the audio to be played based on the number of audio playback devices, and playing local audio of different frequency bands through different audio playback devices specifically includes: Get the audio to be played, count the number of audio playback devices and the frequency range of the audio to be played; Dividing the frequency range according to the number of audio playback devices to obtain a plurality of local frequency band ranges, wherein the local frequency band ranges include an upper frequency limit and a lower frequency limit; Different filters are set according to the local frequency band range, and the audio to be played is filtered through different filters to obtain local audio in different frequency bands, which is played through the audio playback device; The steps of picking up sound through the feedback pickup to obtain feedback frequency-divided audio, positioning the input pickup, and performing feedback adjustment on the input pickup based on the feedback frequency-divided audio specifically include: Picking up sound through a feedback pickup to obtain feedback frequency-divided audio, filtering the feedback frequency-divided audio, and extracting independent frequency-divided audio; During the working process, the audio player communicates with the Bluetooth module in the input pickup in real time to determine the position of the input pickup in the room; According to the distance between the audio playback device and the input pickup, the independent frequency-divided audio is superimposed to obtain feedback suppression audio, and the sound recorded by the input pickup is suppressed by the feedback suppression audio; When constructing and setting up the audio playback system, the audio playback device and the feedback pickup are set at a fixed position. In the subsequent use process, the positions of the audio playback device and the feedback pickup are not changed, and the input pickup is kept fixed before it is officially put into use. When it is officially used, the input pickup can be moved in the playback venue, that is, before the configuration is completed, the input pickup is in a temporarily fixed state, and the two sets of feedback pickups and the input pickup are not collinear; Play the test audio, record the playing time of the test audio and the time when the test audio is received by the feedback pickup and the input pickup, so as to calculate the distance between each audio playback device and the feedback pickup and the input pickup according to the propagation speed of sound. The coordinates of each audio playback device in the three-dimensional coordinate system can be determined through three sets of distance values. After the test is completed, the position of the input pickup can be moved at will; The step of obtaining the audio to be played, dividing the audio to be played based on the number of audio playback devices, and playing local audio of different frequency bands through different audio playback devices includes setting different filters according to the local frequency band range, constructing filters, filtering the audio to be played to obtain local audio corresponding to each local frequency band range, and playing the local audio through the audio playback device. When playing, multiple local audios belonging to the same audio playback device are collectively referred to as a whole, and played through the corresponding audio playback device; The feedback pickup is used to pick up the sound. At this time, multiple audio playback devices will work synchronously. The distances between the audio playback devices and the feedback pickups are different. Therefore, during the playback process, the sound emitted by the audio playback devices will first reach different feedback pickups. A filter is set in the feedback pickup. Each feedback pickup corresponds to multiple audio playback devices. The feedback frequency-divided audio is filtered by the filter to obtain the local audio played by the corresponding audio playback device. The distance between the audio playback device and the input pickup is calculated to determine the playback time difference of each independent frequency-divided audio. The feedback suppression audio corresponding to the audio playback device is aligned based on the playback time difference to obtain the feedback suppression audio. Then, a sound wave signal with an anti-phase is generated based on the feedback suppression audio, thereby offsetting the sound played by the audio playback device detected by the input pickup and achieving the effect of suppressing howling.

2. An anti-howling system for audio equipment, characterized in that: The system comprises: A playback system construction module, used to construct and set up an audio playback system, wherein the audio playback system includes two groups of feedback pickups, one group of input pickups, and multiple groups of audio playback devices, wherein both the audio playback devices and the input pickups are equipped with a built-in Bluetooth module; The device positioning module is used to call the preset test audio, independently control each audio playback device according to the test audio, build a three-dimensional coordinate system, and determine the position of the feedback pickup and multiple groups of audio playback devices; The audio frequency division module is used to obtain the audio to be played, perform frequency division processing on the audio to be played based on the number of audio playback devices, and play local audio of different frequency bands through different audio playback devices; A howling suppression module is used to pick up sound through a feedback pickup to obtain feedback frequency-divided audio, locate the input pickup, and perform feedback adjustment on the input pickup based on the feedback frequency-divided audio; The device positioning module includes: The audio playback unit is used to call the preset test audio, import the test audio into each audio playback device, and play it in turn through the audio playback devices; The device testing unit is used to synchronously pick up sound through the feedback pickup and the input pickup when the audio playback device is playing, so as to obtain multiple groups of picked-up audio; A position identification unit, used to construct a three-dimensional coordinate system, determine the coordinates of the feedback pickup and the input pickup, and determine the position of each audio playback device based on the picked-up audio; The audio frequency division module comprises: A device information acquisition unit, used to acquire the audio to be played, count the number of audio playback devices and the frequency range of the audio to be played; A frequency range division unit, used for dividing the frequency range according to the number of audio playback devices to obtain a plurality of local frequency band ranges, wherein the local frequency band ranges include an upper frequency limit and a lower frequency limit; The audio filter unit is used to set different filters according to the local frequency band range, filter the audio to be played through different filters, obtain local audio in different frequency bands, and play it through the audio playback device; The howling suppression module comprises: The audio extraction unit is used to pick up sound through a feedback pickup to obtain feedback frequency-divided audio, filter the feedback frequency-divided audio, and extract independent frequency-divided audio; A Bluetooth positioning unit is used to determine the position of the input pickup in the room through real-time communication between the audio playback device and the Bluetooth module in the input pickup during operation; An audio suppression unit, used to perform superposition processing on the independent frequency-divided audio according to the distance between the audio playback device and the input pickup, to obtain feedback suppression audio, and suppress the sound recorded by the input pickup through the feedback suppression audio; When constructing and setting up the audio playback system, the playback system construction module sets the audio playback device and the feedback pickup at a fixed position. In the subsequent use process, the position of the audio playback device and the feedback pickup is not changed, and the input pickup is kept in a fixed position before it is officially put into use. When it is officially used, the input pickup can be moved in the playback venue, that is, before the configuration is completed, the input pickup is in a temporarily fixed state, and the two sets of feedback pickups and the input pickup are not collinear; The device positioning module is also used to play the test audio, record the playing time of the test audio and the time when the test audio is received by the feedback pickup and the input pickup, so as to calculate the distance between each audio playback device and the feedback pickup and the input pickup according to the propagation speed of sound. The coordinates of each audio playback device in the three-dimensional coordinate system can be determined through three sets of distance values. After the test is completed, the position of the input pickup can be moved at will; The audio frequency division module is used to set different filters according to the local frequency band range. By constructing the filter, the audio to be played is filtered to obtain the local audio corresponding to each local frequency band range, and the local audio is played through the audio playback device. When playing, multiple local audios belonging to the same audio playback device are collectively referred to as a whole and played through the corresponding audio playback device; The howling suppression module picks up sound through the feedback pickup. At this time, multiple audio playback devices will work synchronously. The distances between the audio playback devices and the feedback pickups are different. Therefore, during the playback process, the sound emitted by the audio playback device will first reach different feedback pickups. A filter is set in the feedback pickup. Each feedback pickup corresponds to multiple audio playback devices. The feedback frequency-divided audio is filtered through the filter to obtain the local audio played by the corresponding audio playback device. The howling suppression module is also used to calculate the distance between the audio playback device and the input pickup, determine the playback time difference of each independent frequency-divided audio, align the feedback suppression audio corresponding to the audio playback device based on the playback time difference, and obtain the feedback suppression audio, and then generate an anti-phase sound wave signal based on the feedback suppression audio, thereby offsetting the sound played by the audio playback device detected by the input pickup, and achieving the effect of suppressing howling.

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