A method and system for controlling the pickup state of a variable directional pickup

Abstract

The present invention relates to the field of acoustic technology, and is a method and system for controlling the pickup state of a variable directional microphone, comprising: confirming a pickup test unit, using the pickup test unit to perform a directional coordinate test on a pre-built test microphone, confirming a target cardioid space and a target bidirectional space in a target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set, respectively, using the activated variable directional microphone to perform real-time sound pickup on a target sound source in a sound control environment, using a four-element cross microphone array to perform a sound source localization operation on the target sound source, performing a mode correction operation on the variable directional microphone based on the target sound source point, the target cardioid space and the target bidirectional space, obtaining a target microphone, until a preset pickup end instruction is received, obtaining a target recording file, and completing the pickup state control of the microphone. The present invention can realize the automatic control of the pickup mode in the variable directional microphone, and improve the recording sound quality of the variable directional microphone.

Description

Technical Field

[0001] The present invention relates to the field of acoustic technology, and in particular to a method, system, electronic device and computer-readable storage medium for controlling the sound pickup state of a variable directional microphone. Background Art

[0002] With the continuous development of information technology, microphones have been widely used in many fields. Especially in scenarios such as voice communication, conference systems, smart homes, and broadcast recording, microphones are the main sound input devices, and the regulation of their pickup status has an important impact on the audio quality. Omnidirectional microphones can evenly collect sound signals from all directions and are suitable for environments that require wide sound reception. However, in a high-noise background, omnidirectional microphones are easily interfered by environmental noise, resulting in reduced sound quality. Unidirectional microphones can focus on the sound source in a specific direction, thereby effectively isolating background noise, but their pickup range is relatively narrow.

[0003] Currently, there is a variable-directional pickup that can switch between multiple pickup modes (cardioid, bidirectional, and omnidirectional). The variable-directional pickup can switch its pickup mode according to user needs to adapt to different sound environments.

[0004] Although the existing variable directional microphone can adjust the pickup state, the existing technology basically uses manual switching to adjust the pickup mode, lacks intelligent adjustment function, and cannot automatically adjust its pickup mode according to the movement of the sound source, resulting in the sound quality of the recorded file obtained by picking up the sound cannot meet the needs of users in an environment where the sound source position changes frequently. Therefore, a method for adjusting the pickup state is urgently needed to achieve intelligent adjustment of the pickup state of the variable directional microphone. Summary of the invention

[0005] The present invention provides a method for controlling the pickup state of a variable directional microphone and a computer-readable storage medium, the main purpose of which is to realize automatic control of the pickup mode in the variable directional microphone and improve the recording sound quality of the variable directional microphone.

[0006] To achieve the above object, the present invention provides a method for controlling the pickup state of a variable directional pickup, comprising:

[0007] Confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk;

[0008] Using a sound pickup test unit to perform a directional coordinate test on a pre-built test sound pickup, and obtaining a cardioid coordinate set and a bidirectional coordinate set;

[0009] receiving a sound control instruction, and confirming a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone, and a four-element cross microphone array, wherein the variable directional microphone is in the shape of a cylinder;

[0010] A target space coordinate system is constructed based on a variable directional pickup and a four-element cross microphone array, and a target cardioid space and a target bidirectional space are respectively identified in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set;

[0011] The variable directional microphone is started, and the target sound source in the sound control environment is picked up in real time by using the started variable directional microphone, and the time interval is recorded in real time with the time when the variable directional microphone is started as the starting point to obtain the sound picking time interval;

[0012] A four-element cross microphone array is used to perform a sound source localization operation on the target sound source to obtain the three-dimensional coordinates of the sound source, and the target sound source point is confirmed in the target space coordinate system based on the three-dimensional coordinates of the sound source;

[0013] Based on the target sound source point, the target cardioid space and the target bidirectional space, a mode correction operation is performed on the variable directional microphone to obtain a target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode;

[0014] When the sound pickup time interval reaches a preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is taken as the starting point and the time interval is recorded in real time to obtain an updated time interval, the updated time interval is used as the sound pickup time interval, the target pickup is used as a variable directional pickup, and the process returns to the step of performing a sound source localization operation on the target sound source using a four-element cross microphone array until a preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the pickup is completed.

[0015] Optionally, the four-element cross microphone array includes: a first microphone, a second microphone, a third microphone and a fourth microphone, the positions of the first microphone, the second microphone, the third microphone and the fourth microphone are all located on a circle with the center of gravity of the variable directional pickup as the center, the distances between the first microphone, the second microphone, the third microphone and the fourth microphone and the variable directional pickup are all preset initial distances, the positions of the first microphone and the third microphone are all located on a straight line where the axis of the cylinder of the variable directional pickup is located, and the vertical distance between the first microphone and the upper bottom surface of the cylinder of the variable directional pickup is smaller than the vertical distance between the first microphone and the lower bottom surface of the cylinder of the variable directional pickup, the vertical distance between the third microphone and the lower bottom surface of the cylinder of the variable directional pickup is smaller than the vertical distance between the third microphone and the upper bottom surface of the cylinder of the variable directional pickup, and the straight line where the center of gravity of the second microphone and the center of gravity of the fourth microphone are located is perpendicular to the straight line where the axis of the cylinder of the variable directional pickup is located.

[0016] Optionally, the method of using the sound pickup test unit to perform a pointing coordinate test on a pre-built test sound pickup to obtain a cardioid coordinate set and a bidirectional coordinate set includes:

[0017] Fixing the test pickup at the center of the center disk of the pickup test unit to obtain a center pickup, wherein the center pickup is in the shape of a cylinder, and the axis of the cylinder of the center pickup is parallel to the plane where the center disk is located, wherein the modes of the center pickup include: a cardioid directional test mode and a bidirectional test mode;

[0018] The center of gravity of the central pickup is taken as a pole, and a polar coordinate system is constructed based on the pole, wherein the direction from the center of gravity of the central pickup to the center of the upper bottom surface of the cylinder of the central pickup is taken as the direction of the polar axis of the polar coordinate system;

[0019] The test position is confirmed based on the polar coordinate system, wherein the test position is located on the outer ring turntable, and the corresponding polar coordinates of the test position in the polar coordinate system are preset initial polar coordinates, wherein the initial polar coordinates are as follows:

[0020]

[0021] in, is a preset initial radius, and the initial radius is larger than the radius of the central disk;

[0022] Fix the standard sound source at the test position on the outer ring turntable to obtain the test sound source;

[0023] Set the center pickup mode to the cardioid test mode to obtain the first pickup;

[0024] The outer ring turntable is rotated clockwise to obtain a rotating turntable, wherein the rotation angular velocity of the outer ring turntable when rotating clockwise is preset, and the target rotation time interval is calculated based on the rotation angular velocity, wherein the calculation formula of the target rotation time interval is as follows:

[0025]

[0026] in, is the target rotation time interval, is the angular velocity of rotation;

[0027] When it is confirmed that the test sound source rotates clockwise with the rotating turntable, the test sound source is started, the time of starting the test sound source is recorded to obtain the start time, and the start time is used as the starting point and the time interval is recorded in real time to obtain the moving time interval;

[0028] A test sound wave is generated by using the started test sound source, and the test sound wave is collected based on a preset collection frequency and a first pickup. When the moving time interval is equal to the target rotation time interval, a plurality of signal time groups are obtained, wherein the signal time group includes: a test voltage signal and a collection time, wherein the test voltage signal is a voltage signal output when the first pickup collects the test sound wave, and the collection time is the time when the first pickup collects the test sound wave;

[0029] The following operations are performed for each of the multiple signal time groups:

[0030] The estimated limit distance is calculated based on the test voltage signal in the signal time group, and the acquisition angle is calculated based on the acquisition time, start time and rotation angular velocity. The calculation formula is as follows:

[0031]

[0032] in, is the acquisition angle, is the collection time, is the start time;

[0033] The test polar coordinates are obtained based on the estimated limit distance and acquisition angle, where the test polar coordinates are as follows:

[0034] )

[0035] in, To estimate the limit distance;

[0036] Summarize the test polar coordinates to obtain a cardioid coordinate set;

[0037] Obtain a bidirectional coordinate set based on the center pickup, bidirectional test pattern, outer ring turntable and test sound source.

[0038] Optionally, calculating the estimated limit distance according to the test voltage signal in the signal time group includes:

[0039] Obtain the fluctuation value of the test voltage signal and calculate the estimated limit distance based on the fluctuation value. The calculation formula is as follows:

[0040]

[0041] in, To estimate the limit distance, is the fluctuation value, It is the preset standard fluctuation value.

[0042] Optionally, the step of constructing a target space coordinate system based on a variable directional microphone and a four-element cross microphone array includes:

[0043] The center of gravity of the variable directional microphone is taken as the origin of space, and a target space coordinate system is constructed based on the origin of space, wherein the direction from the center of the lower bottom surface of the cylinder of the variable directional microphone to the center of the upper bottom surface of the cylinder of the variable directional microphone is taken as the positive direction of the x-axis of the target space coordinate system, a straight line passing through the origin of space, perpendicular to the x-axis and parallel to the plane where the four-element cross microphone array is located is taken as the y-axis of the target space coordinate system, and a straight line passing through the origin of space, perpendicular to the x-axis and perpendicular to the y-axis is taken as the z-axis of the target space coordinate system.

[0044] Optionally, the identifying a target cardioid space and a target bidirectional space in a target space coordinate system based on the cardioid coordinate set and the bidirectional coordinate set respectively includes:

[0045] For each test polar coordinate in the cardioid coordinate set, perform the following operations:

[0046] Confirm the three-dimensional space coordinates based on the estimated limit distance and acquisition angle in the test polar coordinates, where the three-dimensional space coordinates are as follows:

[0047]

[0048] in, is the cosine function, is a sine function;

[0049] Summarize the three-dimensional space coordinates to obtain multiple three-dimensional space coordinates, and fit the multiple three-dimensional space coordinates in the target space coordinate system to obtain a cardioid curve;

[0050] The surface enclosed by the cardioid curve and the x-axis of the target space coordinate system is taken as the cardioid surface;

[0051] In the target space coordinate system, a rotation operation is performed on the cardioid surface using the x-axis of the target space coordinate system as a rotation axis to obtain a target cardioid space, wherein the target cardioid space is a space swept by the cardioid surface during the rotation process;

[0052] The target bidirectional space is obtained based on the bidirectional coordinate set and the target space coordinate system.

[0053] Optionally, performing a sound source localization operation on a target sound source using a four-element cross microphone array to obtain a three-dimensional coordinate of the sound source includes:

[0054] confirming a target sound wave based on a target sound source, wherein the target sound wave is a sound wave generated by the target sound source;

[0055] Turn on the first microphone, the second microphone, the third microphone and the fourth microphone in the four-element cross microphone array, and record the time when the first microphone, the second microphone, the third microphone and the fourth microphone in the four-element cross microphone array are turned on to obtain a starting time, and take the starting time as a starting point and record the time interval in real time to obtain an analysis time interval;

[0056] The target sound waves are collected by using the first microphone, the second microphone, the third microphone and the fourth microphone respectively after being turned on, until the analysis time interval reaches the preset target time interval, and the first microphone, the second microphone, the third microphone and the fourth microphone are turned off to obtain the first sound signal, the second sound signal, the third sound signal and the fourth sound signal;

[0057] Determine the midpoint time interval and the quarter time interval based on the target time interval, wherein the midpoint time interval is half of the target time interval and the quarter time interval is one quarter of the target time interval;

[0058] Confirm the midpoint time based on the start time and the midpoint time interval, wherein the time interval between the midpoint time and the start time is the midpoint time interval, and the midpoint time lags behind the start time; confirm the quarter-minute time based on the start time and the quarter-minute time interval, wherein the time interval between the start time and the quarter-minute time is the quarter-minute time interval, and the quarter-minute time lags behind the start time; confirm the end time based on the midpoint time and the quarter-minute time interval, wherein the time interval between the end time and the midpoint time is the quarter-minute time interval, and the end time lags behind the midpoint time;

[0059] Determine the time interception range based on the midpoint time and the quarter time, wherein the minimum value of the time interception range is the quarter time and the maximum value of the time interception range is the midpoint time;

[0060] Intercepting the first sound signal based on the time interception range to obtain a first intercepted signal;

[0061] Confirming the cutting start time based on the preset cutting time interval and the starting time, wherein the cutting time interval is less than the target time interval, and the time interval between the cutting start time and the starting time is the cutting time interval, and the cutting start time lags behind the starting time; confirming the cutting end time based on the cutting start time and the four-minute time interval, wherein the time interval between the cutting start time and the cutting end time is the four-minute time interval, and the cutting end time lags behind the cutting start time;

[0062] Acquire a comparison interception range based on the cutting start time and the cutting end time, and perform a signal interception operation on the second sound signal based on the comparison interception range to obtain a second intercepted signal;

[0063] The unit time difference is calculated according to the cutting end point time and the midpoint time, where the calculation formula of the unit time difference is as follows:

[0064]

[0065] in, is the unit time difference, is the midpoint time, The cutting end time;

[0066] Performing a translation operation on the second intercepted signal based on the unit time difference to obtain a second translated signal;

[0067] The cross-correlation index between the first intercepted signal and the second translated signal is calculated, wherein the calculation formula of the cross-correlation index is as follows:

[0068]

[0069] in, is the cross-correlation index, is the first intercept signal, is the second translation signal, For four minutes;

[0070] integrating the cross-correlation index and the unit time difference into a correlation data group, storing the correlation data group in a pre-constructed second memory, and obtaining a second target memory;

[0071] The second target memory is used as the second memory, the cutting start time is used as the starting time, and the process returns to the step of confirming the cutting start time based on the preset cutting time interval and the starting time, until the cutting end time is greater than or equal to the end time, and a plurality of related data groups are extracted from the second target memory;

[0072] The correlation data group with the largest cross-correlation index among the multiple correlation data groups is recorded as the target data group, and the unit time difference in the target data group is recorded as the one-two time difference of sound transmission;

[0073] Acquire a sound transmission time difference of one-three based on the first intercepted signal, the cutting time interval, the starting time, the third sound signal and the pre-constructed third memory, and acquire a sound transmission time difference of one-four based on the first intercepted signal, the cutting time interval, the starting time, the fourth sound signal and the pre-constructed fourth memory;

[0074] The three-dimensional coordinates of the sound source are calculated based on the one-two time difference, the one-three time difference and the four-time difference.

[0075] Optionally, the calculating the three-dimensional coordinates of the sound source according to the one-two time difference of sound transmission, the one-three time difference of sound transmission and the one-four time difference of sound transmission includes:

[0076] The distance of the sound source is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows:

[0077]

[0078] in, is the sound source distance, is the preset sound speed, , and They are the sound transmission time difference of one and two, the sound transmission time difference of one and three, and the sound transmission time difference of one and four;

[0079] The plane angle is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows:

[0080]

[0081] in, is the plane angle, is the inverse tangent function;

[0082] The altitude angle is calculated based on the time difference of one to two, the time difference of one to three, the time difference of one to four and the initial distance. The calculation formula is as follows:

[0083]

[0084] in, is the altitude angle, is the inverse sine function, is the initial distance;

[0085] The three-dimensional coordinates of the sound source are obtained according to the sound source distance, plane angle and altitude angle, where the three-dimensional coordinates of the sound source are as follows:

[0086]

[0087] in, is a sine function, is the cosine function.

[0088] Optionally, performing a pattern correction operation on the variable directional microphone based on the target sound source point, the target cardioid space, and the target bidirectional space to obtain the target microphone includes:

[0089] Determine whether the target sound source point is located in the target cardioid space, and if the target sound source point is located in the target cardioid space, set the mode of the variable directional microphone to a cardioid directional mode to obtain a cardioid microphone;

[0090] If the target sound source point is not located in the target cardioid space, it is determined whether the target sound source point is located in the target bidirectional space; if the target sound source point is located in the target bidirectional space, the mode of the variable directional microphone is set to a bidirectional mode to obtain a bidirectional microphone; otherwise, the mode of the variable directional microphone is set to an omnidirectional mode to obtain an omnidirectional microphone;

[0091] The cardioid pickup, the bidirectional pickup or the omnidirectional pickup is recorded as a target pickup.

[0092] To achieve the above object, the present invention also provides a sound pickup state control system of a variable directional sound pickup, comprising:

[0093] A sound pickup direction test module is used to confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer turntable surrounds the central disk. The sound pickup test unit is used to perform a direction coordinate test on the pre-built test pickup to obtain a cardioid coordinate set and a bidirectional coordinate set;

[0094] A sound pickup space confirmation module is used to receive a sound control instruction, and confirm a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional sound pickup, and a four-element cross microphone array, wherein the variable directional sound pickup is in the shape of a cylinder, a target space coordinate system is constructed based on the variable directional sound pickup and the four-element cross microphone array, and a target cardioid space and a target bidirectional space are confirmed in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set respectively;

[0095] A sound pickup pattern correction module is used to start a variable directional sound pickup, use the started variable directional sound pickup to pick up the target sound source in the sound control environment in real time, take the time when the variable directional sound pickup is started as the starting point and record the time interval in real time to obtain the sound pickup time interval, use a four-element cross microphone array to perform a sound source positioning operation on the target sound source to obtain the three-dimensional coordinates of the sound source, confirm the target sound source point in the target space coordinate system based on the three-dimensional coordinates of the sound source, perform a pattern correction operation on the variable directional sound pickup based on the target sound source point, the target cardioid space and the target bidirectional space to obtain the target sound pickup, wherein the modes of the variable directional sound pickup include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode;

[0096] The sound pickup step loop module is used to, when the sound pickup time interval reaches a preset sound pickup threshold, take the time when the sound pickup time interval reaches the preset sound pickup threshold as the starting point and record the time interval in real time, obtain an updated time interval, use the updated time interval as the sound pickup time interval, use the target pickup as a variable directional pickup, and return to the step of performing a sound source localization operation on the target sound source using a four-element cross microphone array until a preset sound pickup end instruction is received, obtain a target recording file, and complete the sound pickup state regulation of the pickup.

[0097] In order to solve the above problem, the present invention further provides an electronic device, the electronic device comprising:

[0098] a memory storing at least one instruction; and

[0099] The processor executes the instructions stored in the memory to implement the above-mentioned method for controlling the sound pickup state of the variable directional pickup.

[0100] In order to solve the above problem, the present invention also provides a computer-readable storage medium, in which at least one instruction is stored. The at least one instruction is executed by a processor in an electronic device to implement the above-mentioned method for controlling the sound pickup state of the variable directional pickup.

[0101] The present invention solves the problem described in the background technology. The present invention confirms a sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk. It can be seen that the embodiment of the present invention provides a complete and closed test environment for subsequent pointing coordinate testing by confirming the sound pickup test unit, thereby improving the accuracy of the pointing coordinate test of the test pickup. Then, the sound pickup test unit is used to perform a pointing coordinate test on the pre-constructed test pickup to obtain a cardioid coordinate set and a bidirectional coordinate set. It can be seen that the embodiment of the present invention obtains a cardioid coordinate set and a bidirectional coordinate set corresponding to two test modes of the test pickup by testing. Since the test microphone is of the same model as the variable directional microphone, a reference is provided for the subsequent variable directional microphone to construct a target cardioid space and a target bidirectional space, a sound control instruction is received, and a sound control environment is confirmed based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone and a four-element cross microphone array, wherein the shape of the variable directional microphone is a cylinder. It can be seen that the embodiment of the present invention provides a necessary environment for the subsequent variable directional microphone to perform real-time sound pickup on the target sound source and the four-element cross microphone array to perform sound source localization on the target sound source by confirming the sound control environment, and a target space coordinate system is constructed based on the variable directional microphone and the four-element cross microphone array, respectively based on the cardioid coordinate set and the bidirectional coordinate set. The target cardioid space and the target bidirectional space are confirmed in the target space coordinate system. It can be seen that the embodiment of the present invention confirms the optimal recording range of the variable directional microphone in space under different modes by confirming the target cardioid space and the target bidirectional space, which provides a basis for subsequent mode correction of the variable directional microphone. The variable directional microphone is started, and the started variable directional microphone is used to pick up the target sound source in the sound control environment in real time. The time when the variable directional microphone is started is used as the starting point and the time interval is recorded in real time to obtain the pickup time interval. The sound source positioning operation is performed on the target sound source using the four-element cross microphone array to obtain the three-dimensional coordinates of the sound source. The target sound source point is confirmed in the target space coordinate system based on the three-dimensional coordinates of the sound source. It can be seen that the present invention The embodiment performs a sound source localization operation on the target sound source through a four-element cross microphone array, thereby confirming the position of the target sound source, providing a basis for subsequent mode correction of the variable directional microphone, and performing a mode correction operation on the variable directional microphone based on the target sound source point, the target cardioid space and the target bidirectional space to obtain the target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode. It can be seen that the embodiment of the present invention determines whether the position of the target sound source is in the target cardioid space or the target bidirectional space, thereby accurately switching the mode of the variable directional microphone, thereby realizing automatic control of the pickup mode of the variable directional microphone, and by accurately switching the pickup mode of the variable directional microphone,The variable directional microphone pickup effect on the target sound source is always kept in the best state, thereby improving the recording sound quality of the variable directional microphone pickup. When the sound pickup time interval reaches the preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is used as the starting point and the time interval is recorded in real time to obtain an updated time interval. The updated time interval is used as the sound pickup time interval, and the target microphone pickup is used as the variable directional microphone pickup. The step of performing the sound source localization operation on the target sound source using the four-element cross microphone array is returned until the preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the microphone pickup is completed. It can be seen that the embodiment of the present invention constructs a loop process by setting the sound pickup threshold, and repeatedly returns to the step of performing the sound source localization operation on the target sound source using the four-element cross microphone array, thereby dynamically adjusting the sound pickup mode of the microphone pickup, realizing the automatic regulation of the sound pickup mode, and finally completing the sound pickup when the sound pickup end instruction is received, generating a high-quality target recording file, and improving the recording sound quality of the variable directional microphone pickup. Therefore, the present invention can realize the automatic regulation of the sound pickup mode in the variable directional microphone pickup, and improve the recording sound quality of the variable directional microphone pickup. BRIEF DESCRIPTION OF THE DRAWINGS

[0102] Figure 1 A schematic flow chart of a method for controlling the sound pickup state of a variable directional pickup provided by an embodiment of the present invention;

[0103] Figure 2 A schematic diagram of the positional relationship between a variable directional microphone and a four-element cross microphone array in a method for controlling the sound pickup state of a variable directional microphone provided in an embodiment of the present invention;

[0104] Figure 3 A functional module diagram of a sound pickup state control system for a variable directional sound pickup provided by an embodiment of the present invention;

[0105] Figure 4 A schematic structural diagram of an electronic device for implementing the method for controlling the sound pickup state of the variable directional microphone provided in one embodiment of the present invention.

[0106] Description of reference numerals:

[0107] 201. First microphone; 202. Second microphone; 203. Third microphone; 204. Fourth microphone; 205. Variable directional microphone; 206. Upper bottom surface of variable directional microphone; 1. Electronic device; 10. Processor; 11. Memory; 12. Bus.

[0108] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0109] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0110] The embodiment of the present application provides a method for regulating the pickup state of a variable directional microphone. The execution subject of the method for regulating the pickup state of a variable directional microphone includes but is not limited to at least one of the electronic devices such as a server and a terminal that can be configured to execute the method provided by the embodiment of the present application. In other words, the method for regulating the pickup state of a variable directional microphone can be executed by software or hardware installed on a terminal device or a server device, and the software can be a blockchain platform. The server includes but is not limited to: a single server, a server cluster, a cloud server or a cloud server cluster, etc.

[0111] Reference Figure 1 FIG. 1 is a flow chart of a method for controlling the sound pickup state of a variable directional microphone provided by an embodiment of the present invention. In this embodiment, the method for controlling the sound pickup state of a variable directional microphone includes:

[0112] S1. Confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk.

[0113] It should be explained that the pickup test unit is a laboratory that integrates a soundproof room, a standard sound source and a layered turntable, and can perform pointing coordinate tests on the test pickup. The standard sound source is a device that can convert electrical signals into sound signals. When an electrical signal is input into the standard sound source, the standard sound source will emit a corresponding sound signal according to the characteristics of the electrical signal, such as frequency, amplitude, etc. The soundproof room is a room that can isolate external noise and provide a quiet environment for pointing coordinate testing. The layered turntable is a device composed of a central disc and an outer ring turntable. The central disc is a disc made of metal, and the outer ring turntable is a ring surrounding the central disc. The outer ring turntable can rotate at a certain angular velocity with the center of the central disc as the center of rotation, and the central disc is fixed when the outer ring turntable rotates.

[0114] S2. Use a sound pickup test unit to perform a directional coordinate test on a pre-built test sound pickup to obtain a cardioid coordinate set and a bidirectional coordinate set.

[0115] In detail, the method of using the sound pickup test unit to perform a directional coordinate test on a pre-built test sound pickup to obtain a cardioid coordinate set and a bidirectional coordinate set includes:

[0116] Fixing the test pickup at the center of the center disk of the pickup test unit to obtain a center pickup, wherein the center pickup is in the shape of a cylinder, and the axis of the cylinder of the center pickup is parallel to the plane where the center disk is located, wherein the modes of the center pickup include: a cardioid directional test mode and a bidirectional test mode;

[0117] The center of gravity of the central pickup is taken as a pole, and a polar coordinate system is constructed based on the pole, wherein the direction from the center of gravity of the central pickup to the center of the upper bottom surface of the cylinder of the central pickup is taken as the direction of the polar axis of the polar coordinate system;

[0118] The test position is confirmed based on the polar coordinate system, wherein the test position is located on the outer ring turntable, and the corresponding polar coordinates of the test position in the polar coordinate system are preset initial polar coordinates, wherein the initial polar coordinates are as follows:

[0119]

[0120] in, is a preset initial radius, and the initial radius is larger than the radius of the central disk;

[0121] Fix the standard sound source at the test position on the outer ring turntable to obtain the test sound source;

[0122] Set the center pickup mode to the cardioid test mode to obtain the first pickup;

[0123] The outer ring turntable is rotated clockwise to obtain a rotating turntable, wherein the rotation angular velocity of the outer ring turntable when rotating clockwise is preset, and the target rotation time interval is calculated based on the rotation angular velocity, wherein the calculation formula of the target rotation time interval is as follows:

[0124]

[0125] in, is the target rotation time interval, is the angular velocity of rotation;

[0126] When it is confirmed that the test sound source rotates clockwise with the rotating turntable, the test sound source is started, the time of starting the test sound source is recorded to obtain the start time, and the start time is used as the starting point and the time interval is recorded in real time to obtain the moving time interval;

[0127] A test sound wave is generated by using the started test sound source, and the test sound wave is collected based on a preset collection frequency and a first pickup. When the moving time interval is equal to the target rotation time interval, a plurality of signal time groups are obtained, wherein the signal time group includes: a test voltage signal and a collection time, wherein the test voltage signal is a voltage signal output when the first pickup collects the test sound wave, and the collection time is the time when the first pickup collects the test sound wave;

[0128] The following operations are performed for each of the multiple signal time groups:

[0129] The estimated limit distance is calculated based on the test voltage signal in the signal time group, and the acquisition angle is calculated based on the acquisition time, start time and rotation angular velocity. The calculation formula is as follows:

[0130]

[0131] in, is the acquisition angle, is the collection time, is the start time;

[0132] The test polar coordinates are obtained based on the estimated limit distance and acquisition angle, where the test polar coordinates are as follows:

[0133] )

[0134] in, To estimate the limit distance;

[0135] Summarize the test polar coordinates to obtain a cardioid coordinate set;

[0136] Obtain a bidirectional coordinate set based on the center pickup, bidirectional test pattern, outer ring turntable and test sound source.

[0137] It should be explained that the test microphone is a capacitive microphone that can switch between multiple microphone directivities (cardioid, bi-directional and omni-directional). The cardioid is a type of microphone directivity. The cardioid is characterized by having the best sound pickup effect for the sound from the front of the microphone, while the sound from other directions will be attenuated. Bi-directional is a type of microphone directivity. The bi-directional is characterized by having the best sound pickup effect for the sound from the front and rear of the microphone, while the sound from other directions will be attenuated, but the sound pickup effect for the sound from the front of the microphone is not as good as the cardioid. Omnidirectional is a type of microphone directivity. The omnidirectional is characterized by having the same sound pickup effect for the sound from all directions of the microphone, but the sound pickup effect for the sound from the front and rear of the microphone is not as good as the cardioid and bi-directional. The technology that the test microphone can switch between multiple modes is a prior art and will not be repeated here.

[0138] In the embodiment of the present invention, the direction in which the lower bottom surface of the cylinder of the test pickup or the variable directional pickup points to the upper bottom surface of the cylinder is regarded as the front of the test pickup or the variable directional pickup, and the direction in which the upper bottom surface of the cylinder of the test pickup and the variable directional pickup points to the lower bottom surface of the cylinder is regarded as the rear of the test pickup or the variable directional pickup.

[0139] It should be understood that the core components of a capacitive pickup are a diaphragm (usually a thin metal film or a film) and a fixed electrode. When the capacitive pickup receives external sound waves, the diaphragm vibrates under the action of the sound waves. These vibrations cause the capacitance between the diaphragm and the fixed electrode to change, and the change in capacitance causes the voltage output by the capacitive pickup to change, thereby converting the sound waves into voltage signals for output. In an embodiment of the present invention, in the cylinder corresponding to the test pickup or the variable directional pickup, the vertical distance between the upper bottom surface of the cylinder and the diaphragm is less than the vertical distance between the lower bottom surface of the cylinder and the diaphragm.

[0140] It can be understood that the cardioid test mode and the bi-directional test mode are two different modes built into the center pickup. When the center pickup is in the cardioid test mode, the microphone directivity of the center pickup is cardioid. When the center pickup is in the bi-directional test mode, the microphone directivity of the center pickup is bi-directional.

[0141] It should be explained that the initial radius is related to the radius of the center disk and the ring width of the outer ring disk. The initial radius must be larger than the radius of the center disk and smaller than the sum of the radius of the center disk and the ring width of the outer ring disk to ensure that the subsequent standard sound source can be fixed on the outer ring disk. Optionally, the rotation angular velocity is 0.1 rad / s.

[0142] Exemplarily, if the time to start the test sound source is 10:00:00, then the start time is 10:00:00, and 10:00:00 is used as the starting point and the time interval is recorded in real time. When it is 10:00:02, the moving time interval is 2 seconds, and when it is 10:00:04, the moving time interval is 4 seconds. An electrical signal with a fixed frequency and amplitude is input into the test sound source, so that the test sound source emits a test sound wave based on the electrical signal. If the collection frequency is once every 2 seconds, the test sound wave is collected once every 2 seconds using the first microphone, and each collection lasts for a period of time. Optionally, the collection lasts for 0.5 seconds. If the time of the first collection is 10:00:00, the second collection is performed at 10:00:02. The first microphone converts the collected sound signal into an analog voltage signal during the collection. The analog voltage signal is the test voltage signal. If the time of the second collection is 10:00:02, the test voltage signal obtained by the second collection is x (A), then the test voltage signal and the time of the second collection together constitute a signal time group: [x (A), 10:00:02]. Finally, when the moving time interval is equal to the target rotation time interval, the signal time groups obtained by multiple collections are summarized to obtain multiple signal time groups.

[0143] It should be understood that the method of obtaining a bidirectional coordinate set based on a central microphone, a bidirectional test mode, an outer ring turntable and a test sound source is the same as the method of obtaining a cardioid coordinate set using a central microphone, a cardioid test mode, an outer ring turntable and a test sound source, and will not be repeated here.

[0144] In detail, the calculating the estimated limit distance according to the test voltage signal in the signal time group includes:

[0145] Obtain the fluctuation value of the test voltage signal and calculate the estimated limit distance based on the fluctuation value. The calculation formula is as follows:

[0146]

[0147] in, To estimate the limit distance, is the fluctuation value, It is the preset standard fluctuation value.

[0148] It should be explained that the fluctuation value refers to the peak-to-peak value of the test voltage signal.

[0149] Exemplarily, the test pickup is placed at a distance of an initial radius from a standard sound source, with the cylindrical upper bottom surface of the test pickup facing the standard sound source, and the standard sound source emits a sound with an intensity of 30 decibels. The peak-to-peak value of the voltage signal output by the test pickup is measured at this time, and the peak-to-peak value is used as the standard fluctuation value.

[0150] It should be understood that when the distance between the test sound source and the first microphone is greater than the estimated limit distance, when the first microphone picks up the sound generated by the test sound source, the peak-to-peak value of the output voltage signal is already lower than the peak-to-peak value of the voltage signal corresponding to the 30 decibel sound, and the sound below 30 decibels is almost inaudible to the human ear, which means that when the distance between the test sound source and the first microphone is greater than the estimated limit distance, the sound quality of the recording obtained when the first microphone picks up the test sound source is already very poor. Therefore, the estimated limit distance reflects the maximum distance that the test sound source can be away from the first microphone when the first microphone picks up the test sound source, under the premise of ensuring that the sound quality of the recording meets the requirements, that is, under the premise of ensuring that the peak-to-peak value of the voltage signal output by the test sound source is greater than the standard fluctuation value.

[0151] S3. Receive a sound control instruction, and confirm a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone and a four-element cross microphone array, wherein the variable directional microphone is in the shape of a cylinder.

[0152] It should be explained that the sound control instruction is initiated by the user of the microphone. The sound control environment is a necessary environment for the variable directional microphone to collect sound. The target sound source refers to the object whose sound needs to be collected in the sound control environment, such as the host or speaker in the meeting. The variable directional microphone is a condenser microphone of the same model as the test microphone, which can switch between multiple microphone directivities (cardioid, bidirectional and omnidirectional) and is pre-installed in a designated position. The designated position can be the center of the conference room.

[0153] For example, Xiao Zhang is a user of the microphone, and now needs to record the speech of the host during a large conference, so he presses the switch on the microphone to initiate the sound control instruction.

[0154] In detail, the four-element cross microphone array includes: a first microphone, a second microphone, a third microphone and a fourth microphone. The positions of the first microphone, the second microphone, the third microphone and the fourth microphone are all located on a circle with the center of gravity of the variable directional pickup as the center of the circle. The distances between the first microphone, the second microphone, the third microphone and the fourth microphone and the variable directional pickup are all preset initial distances. The positions of the first microphone and the third microphone are all located on a straight line where the axis of the cylinder of the variable directional pickup is located, and the vertical distance between the first microphone and the upper bottom surface of the cylinder of the variable directional pickup is smaller than the vertical distance between the first microphone and the lower bottom surface of the cylinder of the variable directional pickup, the vertical distance between the third microphone and the lower bottom surface of the cylinder of the variable directional pickup is smaller than the vertical distance between the third microphone and the upper bottom surface of the cylinder of the variable directional pickup, and the straight line where the center of gravity of the second microphone and the center of gravity of the fourth microphone are located is perpendicular to the straight line where the axis of the cylinder of the variable directional pickup is located.

[0155] It should be explained that the first microphone, the second microphone, the third microphone and the fourth microphone are all microphones with a volume less than 1 cubic decimeter. Optionally, the initial distance is 1 cm.

[0156] It is understandable that the positional relationship between the variable directional microphone and the four-element cross microphone array in the sound control environment is as follows: Figure 2 shown.

[0157] S4. Construct a target space coordinate system based on a variable directional microphone and a four-element cross microphone array, and identify a target cardioid space and a target bidirectional space in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set, respectively.

[0158] In detail, the target space coordinate system is constructed based on the variable directional microphone and the four-element cross microphone array, including:

[0159] The center of gravity of the variable directional microphone is taken as the origin of space, and a target space coordinate system is constructed based on the origin of space, wherein the direction from the center of the lower bottom surface of the cylinder of the variable directional microphone to the center of the upper bottom surface of the cylinder of the variable directional microphone is taken as the positive direction of the x-axis of the target space coordinate system, a straight line passing through the origin of space, perpendicular to the x-axis and parallel to the plane where the four-element cross microphone array is located is taken as the y-axis of the target space coordinate system, and a straight line passing through the origin of space, perpendicular to the x-axis and perpendicular to the y-axis is taken as the z-axis of the target space coordinate system.

[0160] In detail, the step of respectively identifying the target cardioid space and the target bidirectional space in the target space coordinate system based on the cardioid coordinate set and the bidirectional coordinate set includes:

[0161] For each test polar coordinate in the cardioid coordinate set, perform the following operations:

[0162] Confirm the three-dimensional space coordinates based on the estimated limit distance and acquisition angle in the test polar coordinates, where the three-dimensional space coordinates are as follows:

[0163]

[0164] in, is the cosine function, is a sine function;

[0165] Summarize the three-dimensional space coordinates to obtain multiple three-dimensional space coordinates, and fit the multiple three-dimensional space coordinates in the target space coordinate system to obtain a cardioid curve;

[0166] The surface enclosed by the cardioid curve and the x-axis of the target space coordinate system is taken as the cardioid surface;

[0167] In the target space coordinate system, a rotation operation is performed on the cardioid surface using the x-axis of the target space coordinate system as a rotation axis to obtain a target cardioid space, wherein the target cardioid space is a space swept by the cardioid surface during the rotation process;

[0168] The target bidirectional space is obtained based on the bidirectional coordinate set and the target space coordinate system.

[0169] Exemplarily, the test polar coordinates are ), then the three-dimensional space coordinates are .

[0170] Optionally, a cubic spline interpolation method is used to fit the three-dimensional space coordinates, and the technology of fitting the three-dimensional space coordinates using the cubic spline interpolation method is an existing technology and will not be described in detail here.

[0171] It should be understood that the target cardioid space reflects the optimal recording range in space when the variable-directional pickup is in cardioid mode and picks up the target sound source. The target bidirectional space reflects the optimal recording range in space when the variable-directional pickup is in bidirectional mode and picks up the target sound source.

[0172] S5, starting the variable directional microphone, using the started variable directional microphone to pick up the target sound source in the sound control environment in real time, taking the time when the variable directional microphone is started as the starting point and recording the time interval in real time to obtain the sound picking time interval.

[0173] Exemplarily, if the time to start the variable directional microphone is 10:00:00, then taking 10:00:00 as the starting point, at 10:00:02, the sound pickup time interval is 2 seconds, and at 10:20:00, the sound pickup time interval is 20 minutes.

[0174] It should be understood that the use of the activated variable directional microphone to pick up the target sound source in the sound control environment in real time means: using the activated variable directional microphone to record the sound generated by the target sound source in real time. It should be noted that before receiving the preset sound pickup end instruction in the subsequent embodiments, the variable directional microphone has been picking up the target sound source in the sound control environment in real time, and will not be interrupted by the mode correction operation until the sound pickup end instruction is received, and all the sounds recorded in the process of the variable directional microphone picking up the sound in real time are integrated into a sound file, thereby obtaining the target recording file in the subsequent embodiments.

[0175] For example, during a large conference, speakers will often change positions. Therefore, while using the activated variable-directional microphone to pick up the target sound source in the sound control environment in real time, subsequent embodiments also use a four-element cross microphone array to perform sound source localization on the target sound source, thereby updating the pattern of the variable-directional microphone according to the result of the sound source localization, thereby improving the sound quality of the target recording file finally obtained.

[0176] S6. Perform a sound source localization operation on the target sound source using a four-element cross microphone array to obtain the three-dimensional coordinates of the sound source, and confirm the target sound source point in the target space coordinate system based on the three-dimensional coordinates of the sound source.

[0177] In detail, the method of performing a sound source localization operation on a target sound source using a four-element cross microphone array to obtain the three-dimensional coordinates of the sound source includes:

[0178] confirming a target sound wave based on a target sound source, wherein the target sound wave is a sound wave generated by the target sound source;

[0179] Turn on the first microphone, the second microphone, the third microphone and the fourth microphone in the four-element cross microphone array, and record the time when the first microphone, the second microphone, the third microphone and the fourth microphone in the four-element cross microphone array are turned on to obtain a starting time, and take the starting time as a starting point and record the time interval in real time to obtain an analysis time interval;

[0180] The target sound waves are collected by using the first microphone, the second microphone, the third microphone and the fourth microphone respectively after being turned on, until the analysis time interval reaches the preset target time interval, and the first microphone, the second microphone, the third microphone and the fourth microphone are turned off to obtain the first sound signal, the second sound signal, the third sound signal and the fourth sound signal;

[0181] Determine the midpoint time interval and the quarter time interval based on the target time interval, wherein the midpoint time interval is half of the target time interval and the quarter time interval is one quarter of the target time interval;

[0182] Confirm the midpoint time based on the start time and the midpoint time interval, wherein the time interval between the midpoint time and the start time is the midpoint time interval, and the midpoint time lags behind the start time; confirm the quarter-minute time based on the start time and the quarter-minute time interval, wherein the time interval between the start time and the quarter-minute time is the quarter-minute time interval, and the quarter-minute time lags behind the start time; confirm the end time based on the midpoint time and the quarter-minute time interval, wherein the time interval between the end time and the midpoint time is the quarter-minute time interval, and the end time lags behind the midpoint time;

[0183] Determine the time interception range based on the midpoint time and the quarter time, wherein the minimum value of the time interception range is the quarter time and the maximum value of the time interception range is the midpoint time;

[0184] Intercepting the first sound signal based on the time interception range to obtain a first intercepted signal;

[0185] Confirming the cutting start time based on the preset cutting time interval and the starting time, wherein the cutting time interval is less than the target time interval, and the time interval between the cutting start time and the starting time is the cutting time interval, and the cutting start time lags behind the starting time; confirming the cutting end time based on the cutting start time and the four-minute time interval, wherein the time interval between the cutting start time and the cutting end time is the four-minute time interval, and the cutting end time lags behind the cutting start time;

[0186] Acquire a comparison interception range based on the cutting start time and the cutting end time, and perform a signal interception operation on the second sound signal based on the comparison interception range to obtain a second intercepted signal;

[0187] The unit time difference is calculated according to the cutting end point time and the midpoint time, where the calculation formula of the unit time difference is as follows:

[0188]

[0189] in, is the unit time difference, is the midpoint time, The cutting end time;

[0190] Performing a translation operation on the second intercepted signal based on the unit time difference to obtain a second translated signal;

[0191] The cross-correlation index between the first intercepted signal and the second translated signal is calculated, wherein the calculation formula of the cross-correlation index is as follows:

[0192]

[0193] in, is the cross-correlation index, is the first intercept signal, is the second translation signal, For four minutes;

[0194] integrating the cross-correlation index and the unit time difference into a correlation data group, storing the correlation data group in a pre-constructed second memory, and obtaining a second target memory;

[0195] The second target memory is used as the second memory, the cutting start time is used as the starting time, and the process returns to the step of confirming the cutting start time based on the preset cutting time interval and the starting time, until the cutting end time is greater than or equal to the end time, and a plurality of related data groups are extracted from the second target memory;

[0196] The correlation data group with the largest cross-correlation index among the multiple correlation data groups is recorded as the target data group, and the unit time difference in the target data group is recorded as the one-two time difference of sound transmission;

[0197] Acquire a sound transmission time difference of one-three based on the first intercepted signal, the cutting time interval, the starting time, the third sound signal and the pre-constructed third memory, and acquire a sound transmission time difference of one-four based on the first intercepted signal, the cutting time interval, the starting time, the fourth sound signal and the pre-constructed fourth memory;

[0198] The three-dimensional coordinates of the sound source are calculated based on the one-two time difference, the one-three time difference and the four-time difference.

[0199] Exemplarily, if the target sound source is a speaker in a conference room, the target sound wave is the sound wave of the sound generated by the speaker when speaking. If the time when the first microphone, the second microphone, the third microphone, and the fourth microphone in the four-element cross microphone array are turned on is 08:00:00, the starting time is 08:00:00, and at 08:00:01, the analysis time interval is 1 second. If the target time interval is set to 4 seconds, at 08:00:04, the first microphone, the second microphone, the third microphone, and the fourth microphone are turned off, and the sound signals obtained by collecting the target sound wave from 08:00:00 to 08:00:04 by the first microphone, the second microphone, the third microphone, and the fourth microphone are used as the first sound signal, the second sound signal, the third sound signal, and the fourth sound signal. Signal and the fourth sound signal, since the target time interval is 4 seconds, the midpoint time interval and the quarter time interval are 2 seconds and 1 second respectively, since the starting time is 08:00:00, the midpoint time, quarter time and end time are 08:00:02, 08:00:01 and 08:00:03 respectively, so the time interception range is (08:00:01, 08:00:02), since the time period corresponding to the first sound signal is 08:00:00 to 08:00:04, the sound signal with a time period of 08:00:01 to 08:00:02 is intercepted from the first sound signal as the first intercepted signal.

[0200] It should be understood that the cutting time interval should be much smaller than the target time interval. Optionally, the cutting time interval is 0.01 seconds.

[0201] It is understandable that the method of obtaining the comparative interception range based on the cutting start time and the cutting end time is the same as the method of confirming the time interception range based on the midpoint time and the quarter time, and will not be repeated here. The method of performing the signal interception operation on the second sound signal based on the comparative interception range to obtain the second intercepted signal is the same as the method of performing the signal interception operation on the first sound signal based on the time interception range to obtain the first intercepted signal, and will not be repeated here.

[0202] It should be understood that the cross-correlation index reflects the degree of overlap between the waveform corresponding to the first intercepted signal and the waveform corresponding to the second translated signal from the quarter moment to the midpoint moment. The larger the cross-correlation index, the higher the degree of overlap between the waveform corresponding to the first intercepted signal and the waveform corresponding to the second translated signal from the quarter moment to the midpoint moment.

[0203] It should be explained that the second memory, the third memory and the fourth memory are all memories that can store related data groups. The related data group is a data packet that stores the mutual correlation index and the unit time difference.

[0204] It can be understood that the method of obtaining the sound transmission one-three time difference based on the first intercepted signal, cutting time interval, starting moment, third sound signal and pre-constructed third memory and the method of obtaining the sound transmission one-four time difference based on the first intercepted signal, cutting time interval, starting moment, fourth sound signal and pre-constructed fourth memory are the same as the method of obtaining the sound transmission one-two time difference using the first intercepted signal, cutting time interval, starting moment, first sound signal and pre-constructed second memory, and will not be repeated here.

[0205] In detail, performing a translation operation on the second intercepted signal based on the unit time difference to obtain a second translated signal includes:

[0206] confirming a unit time based on the unit time difference, wherein the unit time is an absolute value of the unit time difference;

[0207] Determine whether the unit time difference is a positive number, and if the unit time difference is a positive number, confirm the second forward-shifted signal based on the second intercepted signal and the unit time, wherein the second forward-shifted signal is the second intercepted signal that is shifted forward in time by the unit time;

[0208] If the unit time difference is not a positive number, confirming a second backward-shifted signal based on the second intercepted signal and the unit time, wherein the second backward-shifted signal is the second intercepted signal that is shifted backward in time by the unit time;

[0209] The second forward shift signal or the second backward shift signal is used as a second translation signal.

[0210] For example, if the unit time difference is -1s, if the second intercepted signal is , then the second intercepted signal is shifted backward by 1s on the time axis, that is, the second intercepted signal is Transformed into , This is the second translation signal.

[0211] It should be understood that due to the distance between the first microphone and the second microphone, the time when the sound waves generated by the target sound source reach the first microphone and the second microphone is different. Therefore, there is a time delay between the first sound signal and the second sound signal collected by the first microphone and the second microphone. For example, the second microphone is farther away from the target sound source than the first microphone, so the second sound signal collected by the second microphone will be delayed for a period of time on the time axis compared with the first sound signal collected by the first microphone. Therefore, the embodiment of the present invention performs multiple shift attempts on the time axis through multiple cycles to obtain multiple A second shifted signal is generated, and the cross-correlation index between the second shifted signal and the first intercepted signal is calculated multiple times. Among the multiple cross-correlation indexes, the waveform of the second shifted signal corresponding to the largest cross-correlation index is the one with the highest degree of overlap between the waveforms of the multiple second shifted signals and the first intercepted signal. This means that when the second shifted signal is shifted on the time axis using the unit time difference corresponding to the largest cross-correlation index, the time delay between the second shifted signal and the first intercepted signal can be eliminated. Therefore, the unit time difference corresponding to the largest cross-correlation index is recorded as the sound transmission time difference, that is, the sound transmission time difference reflects the time delay difference between the first sound signal and the second sound signal.

[0212] For example, if the starting time is 8:00:00, the four-minute time interval is 1 second, the midpoint time is 8:00:2.00, and the end time is 8:00:3.00, in the first cycle, if the cutting time interval is 0.01 seconds, the cutting starting time is 8:00:0.01, and the cutting end time is 8:00:1.01. At this time, the midpoint time is subtracted from the cutting end time, and the calculated unit time difference is -0.99 seconds. After the relevant data group is calculated, the relevant data group is stored in the second memory, and then the cutting starting time is used as the starting time to perform In the second cycle, the starting time becomes 8:0:01, and a new cutting start time is calculated to be 8:0:02, and the cutting end time is 8:0:1.02. At this time, the calculated unit time difference is -0.98 seconds, and a related data group is calculated again and stored in the second memory, and so on, until the 300th cycle, when the cutting end time is 8:0:3.00, which is equal to the end time, then the cycle ends, and the 300 related data groups stored in all the cycles are extracted from the second memory.

[0213] In detail, the three-dimensional coordinates of the sound source are calculated according to the one-two time difference, the one-three time difference and the one-four time difference, including:

[0214] The distance of the sound source is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows:

[0215]

[0216] in, is the sound source distance, is the preset sound speed, , and They are the sound transmission time difference of one and two, the sound transmission time difference of one and three, and the sound transmission time difference of one and four;

[0217] The plane angle is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows:

[0218]

[0219] in, is the plane angle, is the inverse tangent function;

[0220] The altitude angle is calculated based on the time difference of one to two, the time difference of one to three, the time difference of one to four and the initial distance. The calculation formula is as follows:

[0221]

[0222] in, is the altitude angle, is the inverse sine function, is the initial distance;

[0223] The three-dimensional coordinates of the sound source are obtained according to the sound source distance, plane angle and altitude angle, where the three-dimensional coordinates of the sound source are as follows:

[0224]

[0225] in, is a sine function, is the cosine function.

[0226] It should be explained that the speed of sound refers to the speed at which sound propagates in the air. The sound source distance refers to the distance between the target sound source and the variable directional pickup.

[0227] For example, a target vector is constructed, where the direction from the origin of the target space coordinate system to the point corresponding to the target sound source in the target space coordinate system is the direction of the target vector, then the angle between the target vector and the unit vector on the positive semi-axis of the x-axis is the plane angle, and the angle between the target vector and the unit vector on the positive semi-axis of the z-axis is the altitude angle. If the sound source distance is 4 meters, the plane angle is 30 degrees, and the altitude angle is 60 degrees, then the three-dimensional coordinates of the sound source are .

[0228] It should be understood that identifying the target sound source point in the target space coordinate system based on the three-dimensional coordinates of the sound source means: finding a point in the target space coordinate system whose coordinates are the three-dimensional coordinates of the sound source and taking the point as the target sound source point.

[0229] S7. Performing a mode correction operation on the variable directional microphone based on the target sound source point, the target cardioid space and the target bidirectional space to obtain a target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode.

[0230] In detail, the method of performing a pattern correction operation on the variable directional microphone based on the target sound source point, the target cardioid space and the target bidirectional space to obtain the target microphone includes:

[0231] Determine whether the target sound source point is located in the target cardioid space, and if the target sound source point is located in the target cardioid space, set the mode of the variable directional microphone to a cardioid directional mode to obtain a cardioid microphone;

[0232] If the target sound source point is not located in the target cardioid space, it is determined whether the target sound source point is located in the target bidirectional space; if the target sound source point is located in the target bidirectional space, the mode of the variable directional microphone is set to a bidirectional mode to obtain a bidirectional microphone; otherwise, the mode of the variable directional microphone is set to an omnidirectional mode to obtain an omnidirectional microphone;

[0233] The cardioid pickup, the bidirectional pickup or the omnidirectional pickup is recorded as a target pickup.

[0234] It can be understood that the cardioid polarity mode, bi-directional mode and omni-directional mode are three different modes built into the variable directional pickup. When the variable directional pickup is in the cardioid polarity mode, the microphone directivity of the variable directional pickup is cardioid; when the variable directional pickup is in the bi-directional mode, the microphone directivity of the variable directional pickup is bi-directional; when the variable directional pickup is in the omni-directional mode, the microphone directivity of the variable directional pickup is omni-directional.

[0235] It should be understood that the embodiment of the present invention improves the sound quality of the target recording file finally obtained by selecting the most suitable mode for the variable directional microphone according to the position of the target sound source point.

[0236] S8. When the sound pickup time interval reaches a preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is taken as the starting point and the time interval is recorded in real time to obtain an updated time interval, and the updated time interval is used as the sound pickup time interval, and the target pickup is used as a variable directional pickup, and the step of performing a sound source localization operation on the target sound source using the four-element cross microphone array is returned until a preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the pickup is completed.

[0237] For example, if the sound pickup threshold is set to 30 seconds, and if the time to start the variable directional microphone is 10:00:00, then from 10:00:00 to 10:00:30, the following process is carried out simultaneously: the variable directional microphone has been recording the meeting, and the initial mode of the variable directional microphone is the omnidirectional mode, and the sound source localization operation is performed on the target sound source through the four-element cross microphone array, and it is confirmed that the mode of the target microphone is the cardioid directional mode, so the mode of the variable directional microphone is switched from the omnidirectional mode to the cardioid directional mode (the switching does not interrupt the recording process), until 10:00:30, the sound pickup threshold is reached, and the recording is resumed at 10:0 0:30 is taken as the starting point, and the time is recorded in real time again to obtain the update time interval (if the update time interval is 2 seconds at 10:00:32), the sound pickup time interval is used as the update time interval and the above process is repeated, that is, from 10:00:30 to 10:01:00, the mode correction is performed again until 10:01:00, the sound pickup time interval reaches the sound pickup threshold again, and so on, until the sound pickup end instruction is received. If the time when the sound pickup end instruction is received is 10:20:00, all the sounds recorded by the variable directional microphone from 10:00:00 to 10:20:00 are integrated into a sound file to obtain the target recording file. Therefore, the embodiment of the present invention continuously performs mode correction on the variable directional microphone in the loop process, so that the sound collected by the variable directional microphone in the entire recording process is always of the best sound quality, thereby improving the sound quality of the target recording file finally obtained.

[0238] The present invention solves the problem described in the background technology. The present invention confirms a sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk. It can be seen that the embodiment of the present invention provides a complete and closed test environment for subsequent pointing coordinate testing by confirming the sound pickup test unit, thereby improving the accuracy of the pointing coordinate test of the test pickup. Then, the sound pickup test unit is used to perform a pointing coordinate test on the pre-constructed test pickup to obtain a cardioid coordinate set and a bidirectional coordinate set. It can be seen that the embodiment of the present invention obtains a cardioid coordinate set and a bidirectional coordinate set corresponding to two test modes of the test pickup by testing. Since the test microphone is of the same model as the variable directional microphone, a reference is provided for the subsequent variable directional microphone to construct a target cardioid space and a target bidirectional space, a sound control instruction is received, and a sound control environment is confirmed based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone and a four-element cross microphone array, wherein the shape of the variable directional microphone is a cylinder. It can be seen that the embodiment of the present invention provides a necessary environment for the subsequent variable directional microphone to perform real-time sound pickup on the target sound source and the four-element cross microphone array to perform sound source localization on the target sound source by confirming the sound control environment, and a target space coordinate system is constructed based on the variable directional microphone and the four-element cross microphone array, respectively based on the cardioid coordinate set and the bidirectional coordinate set. The target cardioid space and the target bidirectional space are confirmed in the target space coordinate system. It can be seen that the embodiment of the present invention confirms the optimal recording range of the variable directional microphone in space under different modes by confirming the target cardioid space and the target bidirectional space, which provides a basis for subsequent mode correction of the variable directional microphone. The variable directional microphone is started, and the started variable directional microphone is used to pick up the target sound source in the sound control environment in real time. The time when the variable directional microphone is started is used as the starting point and the time interval is recorded in real time to obtain the pickup time interval. The sound source positioning operation is performed on the target sound source using the four-element cross microphone array to obtain the three-dimensional coordinates of the sound source. The target sound source point is confirmed in the target space coordinate system based on the three-dimensional coordinates of the sound source. It can be seen that the present invention The embodiment performs a sound source localization operation on the target sound source through a four-element cross microphone array, thereby confirming the position of the target sound source, providing a basis for subsequent mode correction of the variable directional microphone, and performing a mode correction operation on the variable directional microphone based on the target sound source point, the target cardioid space and the target bidirectional space to obtain the target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode. It can be seen that the embodiment of the present invention determines whether the position of the target sound source is in the target cardioid space or the target bidirectional space, thereby accurately switching the mode of the variable directional microphone, thereby realizing automatic control of the pickup mode of the variable directional microphone, and by accurately switching the pickup mode of the variable directional microphone,The variable directional microphone pickup effect on the target sound source is always kept in the best state, thereby improving the recording sound quality of the variable directional microphone pickup. When the sound pickup time interval reaches the preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is used as the starting point and the time interval is recorded in real time to obtain an updated time interval. The updated time interval is used as the sound pickup time interval, and the target microphone pickup is used as the variable directional microphone pickup. The step of performing the sound source localization operation on the target sound source using the four-element cross microphone array is returned until the preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the microphone pickup is completed. It can be seen that the embodiment of the present invention constructs a loop process by setting the sound pickup threshold, and repeatedly returns to the step of performing the sound source localization operation on the target sound source using the four-element cross microphone array, thereby dynamically adjusting the sound pickup mode of the microphone pickup, realizing the automatic regulation of the sound pickup mode, and finally completing the sound pickup when the sound pickup end instruction is received, generating a high-quality target recording file, and improving the recording sound quality of the variable directional microphone pickup. Therefore, the present invention can realize the automatic regulation of the sound pickup mode in the variable directional microphone pickup, and improve the recording sound quality of the variable directional microphone pickup.

[0239] like Figure 3 , which is a functional module diagram of a sound pickup state control system of a variable directional microphone provided by an embodiment of the present invention.

[0240] The pickup state control system 100 of the variable directional pickup of the present invention can be installed in an electronic device. According to the functions to be implemented, the pickup state control system 100 of the variable directional pickup can include a pickup direction test module 101, a pickup space confirmation module 102, a pickup mode correction module 103 and a pickup step loop module 104. The module of the present invention can also be called a unit, which refers to a series of computer program segments that can be executed by an electronic device processor and can complete fixed functions, which are stored in the memory of the electronic device.

[0241] The sound pickup direction test module 101 is used to confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer turntable surrounds the central disk. The sound pickup test unit is used to perform a direction coordinate test on a pre-built test pickup to obtain a cardioid coordinate set and a bidirectional coordinate set;

[0242] The sound pickup space confirmation module 102 is used to receive a sound control instruction, and confirm a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional sound pickup, and a four-element cross microphone array, wherein the variable directional sound pickup is in the shape of a cylinder, a target space coordinate system is constructed based on the variable directional sound pickup and the four-element cross microphone array, and a target cardioid space and a target bidirectional space are confirmed in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set, respectively;

[0243] The sound pickup pattern correction module 103 is used to start the variable directional pickup, use the started variable directional pickup to pick up the target sound source in the sound control environment in real time, take the time when the variable directional pickup is started as the starting point and record the time interval in real time to obtain the sound pickup time interval, use the four-element cross microphone array to perform a sound source positioning operation on the target sound source to obtain the three-dimensional coordinates of the sound source, confirm the target sound source point in the target space coordinate system based on the three-dimensional coordinates of the sound source, perform a pattern correction operation on the variable directional pickup based on the target sound source point, the target cardioid space and the target bidirectional space to obtain the target pickup, wherein the modes of the variable directional pickup include: cardioid directional mode, bidirectional mode and omnidirectional mode;

[0244] The sound pickup step loop module 104 is used to, when the sound pickup time interval reaches the preset sound pickup threshold, take the time when the sound pickup time interval reaches the preset sound pickup threshold as the starting point and record the time interval in real time, obtain an updated time interval, use the updated time interval as the sound pickup time interval, use the target pickup as a variable directional pickup, and return to the step of performing the sound source localization operation on the target sound source using the four-element cross microphone array until a preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the pickup is completed.

[0245] In detail, the modules in the sound pickup state control system 100 of the variable directional pickup in the embodiment of the present invention are used in the same manner as described above. Figure 1 The same technical means as the method for controlling the pickup state of the variable directional pickup described in the text and the like can produce the same technical effects, which will not be repeated here.

[0246] like Figure 4 , which is a schematic diagram of the structure of an electronic device for implementing a method for controlling the sound pickup state of a variable directional microphone provided by an embodiment of the present invention.

[0247] The electronic device 1 may include a processor 10, a memory 11 and a bus 12, and may also include a computer program stored in the memory 11 and executable on the processor 10, such as a method program for controlling the pickup state of a variable directional pickup.

[0248] The memory 11 includes at least one type of readable storage medium, and the readable storage medium includes a flash memory, a mobile hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory, etc.), a magnetic memory, a disk, an optical disk, etc. In some embodiments, the memory 11 may be an internal storage unit of the electronic device 1, such as a mobile hard disk of the electronic device 1. In other embodiments, the memory 11 may also be an external storage device of the electronic device 1, such as a plug-in mobile hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device 1. Further, the memory 11 also includes an internal storage unit of the electronic device 1 and an external storage device. The memory 11 can not only be used to store application software and various types of data installed in the electronic device 1, such as the code of the program of the method for controlling the pickup state of the variable directional pickup, but also can be used to temporarily store data that has been output or is to be output.

[0249] The processor 10 may be composed of an integrated circuit in some embodiments, for example, a single packaged integrated circuit, or a plurality of packaged integrated circuits with the same or different functions, including one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and combinations of various control chips, etc. The processor 10 is the control core (Control Unit) of the electronic device, and uses various interfaces and lines to connect various components of the entire electronic device, and executes or executes programs or modules stored in the memory 11 (such as a program for controlling the sound pickup state of a variable directional pickup, etc.), and calls data stored in the memory 11, so as to execute various functions of the electronic device 1 and process data.

[0250] The bus 12 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus 12 may be divided into an address bus, a data bus, a control bus, etc. The bus 12 is configured to realize connection and communication between the memory 11 and at least one processor 10, etc.

[0251] Figure 4 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 4The structure shown does not constitute a limitation on the electronic device 1, and may include fewer or more components than shown in the figure, or combine certain components, or arrange the components differently.

[0252] For example, although not shown, the electronic device 1 may also include a power source (such as a battery) for supplying power to various components. Preferably, the power source may be logically connected to the at least one processor 10 through a power management device, so that the power management device can realize functions such as charging management, discharging management, and power consumption management. The power source may also include one or more DC or AC power sources, recharging devices, power failure detection circuits, power converters or inverters, power status indicators, and other arbitrary components. The electronic device 1 may also include a variety of sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

[0253] Furthermore, the electronic device 1 may also include a network interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is generally used to establish a communication connection between the electronic device 1 and other electronic devices.

[0254] Optionally, the electronic device 1 may further include a user interface, which may be a display, an input unit (such as a keyboard), or a standard wired interface or a wireless interface. Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, and an OLED (Organic Light-Emitting Diode) touch device. The display may also be appropriately referred to as a display screen or a display unit, which is used to display information processed in the electronic device 1 and to display a visual user interface.

[0255] The program of the method for controlling the pickup state of the variable directional pickup stored in the memory 11 of the electronic device 1 is a combination of multiple instructions. When running in the processor 10, the following can be achieved:

[0256] Confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk;

[0257] Using a sound pickup test unit to perform a directional coordinate test on a pre-built test sound pickup, and obtaining a cardioid coordinate set and a bidirectional coordinate set;

[0258] receiving a sound control instruction, and confirming a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone, and a four-element cross microphone array, wherein the variable directional microphone is in the shape of a cylinder;

[0259] A target space coordinate system is constructed based on a variable directional pickup and a four-element cross microphone array, and a target cardioid space and a target bidirectional space are respectively identified in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set;

[0260] The variable directional microphone is started, and the target sound source in the sound control environment is picked up in real time by using the started variable directional microphone, and the time interval is recorded in real time with the time when the variable directional microphone is started as the starting point to obtain the sound picking time interval;

[0261] A four-element cross microphone array is used to perform a sound source localization operation on the target sound source to obtain the three-dimensional coordinates of the sound source, and the target sound source point is confirmed in the target space coordinate system based on the three-dimensional coordinates of the sound source;

[0262] Based on the target sound source point, the target cardioid space and the target bidirectional space, a mode correction operation is performed on the variable directional microphone to obtain a target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode;

[0263] When the sound pickup time interval reaches a preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is taken as the starting point and the time interval is recorded in real time to obtain an updated time interval, the updated time interval is used as the sound pickup time interval, the target pickup is used as a variable directional pickup, and the process returns to the step of performing a sound source localization operation on the target sound source using a four-element cross microphone array until a preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the pickup is completed.

[0264] Specifically, the specific implementation method of the processor 10 for the above instructions can refer to Figures 1 to 4 The description of the relevant steps in the corresponding embodiments will not be repeated here.

[0265] Furthermore, if the module / unit integrated in the electronic device 1 is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. The computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM).

[0266] The present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor of an electronic device, the computer program can implement:

[0267] Confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk;

[0268] Using a sound pickup test unit to perform a directional coordinate test on a pre-built test sound pickup, and obtaining a cardioid coordinate set and a bidirectional coordinate set;

[0269] receiving a sound control instruction, and confirming a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone, and a four-element cross microphone array, wherein the variable directional microphone is in the shape of a cylinder;

[0270] A target space coordinate system is constructed based on a variable directional pickup and a four-element cross microphone array, and a target cardioid space and a target bidirectional space are respectively identified in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set;

[0271] The variable directional microphone is started, and the target sound source in the sound control environment is picked up in real time by using the started variable directional microphone, and the time interval is recorded in real time with the time when the variable directional microphone is started as the starting point to obtain the sound picking time interval;

[0272] A four-element cross microphone array is used to perform a sound source localization operation on the target sound source to obtain the three-dimensional coordinates of the sound source, and the target sound source point is confirmed in the target space coordinate system based on the three-dimensional coordinates of the sound source;

[0273] Based on the target sound source point, the target cardioid space and the target bidirectional space, a mode correction operation is performed on the variable directional microphone to obtain a target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode;

[0274] When the sound pickup time interval reaches a preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is taken as the starting point and the time interval is recorded in real time to obtain an updated time interval, the updated time interval is used as the sound pickup time interval, the target pickup is used as a variable directional pickup, and the process returns to the step of performing a sound source localization operation on the target sound source using a four-element cross microphone array until a preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the pickup is completed.

[0275] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, systems and methods can be implemented in other ways. For example, the system embodiments described above are only illustrative, and actual implementation may have other division methods.

[0276] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0277] In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0278] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0279] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A method for controlling the pickup state of a variable directional pickup, characterized in that: The method comprises: Confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer ring turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer ring turntable surrounds the central disk; Using a sound pickup test unit to perform a directional coordinate test on a pre-built test sound pickup, and obtaining a cardioid coordinate set and a bidirectional coordinate set; receiving a sound control instruction, and confirming a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional microphone, and a four-element cross microphone array, wherein the variable directional microphone is in the shape of a cylinder; A target space coordinate system is constructed based on a variable directional pickup and a four-element cross microphone array, and a target cardioid space and a target bidirectional space are respectively identified in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set; The variable directional microphone is started, and the target sound source in the sound control environment is picked up in real time by using the started variable directional microphone, and the time interval is recorded in real time with the time when the variable directional microphone is started as the starting point to obtain the sound picking time interval; The target sound source is analyzed by using a four-element cross microphone array to obtain the sound transmission time difference of one and two, one and three, and one and four. The three-dimensional coordinates of the sound source are calculated according to the one-two time difference, the one-three time difference and the one-four time difference of sound transmission, wherein the three-dimensional coordinates of the sound source are calculated according to the one-two time difference, the one-three time difference and the one-four time difference of sound transmission, including: The distance of the sound source is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows: Among them, D sx is the distance from the sound source, v s is the preset sound speed, T 12 , T 13 and T 14 They are the sound transmission time difference of one and two, the sound transmission time difference of one and three, and the sound transmission time difference of one and four; The plane angle is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows: Among them, α x is the plane angle, arctan is the inverse tangent function; The altitude angle is calculated based on the time difference of one to two, the time difference of one to three, the time difference of one to four and the initial distance. The calculation formula is as follows: Among them, β x is the altitude angle, arcsin is the inverse sine function, D x0 is the initial distance; The three-dimensional coordinates of the sound source are obtained according to the sound source distance, plane angle and altitude angle, where the three-dimensional coordinates of the sound source are as follows: (D sx ×sinβ x ×cosα x ,D sx ×sinα x ×sinβ x ,D sx ×cosβ x ) Among them, sin is the sine function and cos is the cosine function; Confirming the target sound source point in the target space coordinate system based on the three-dimensional coordinates of the sound source; Based on the target sound source point, the target cardioid space and the target bidirectional space, a mode correction operation is performed on the variable directional microphone to obtain a target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode and an omnidirectional mode; When the sound pickup time interval reaches a preset sound pickup threshold, the time when the sound pickup time interval reaches the preset sound pickup threshold is taken as the starting point and the time interval is recorded in real time to obtain an updated time interval, the updated time interval is used as the sound pickup time interval, the target pickup is used as a variable directional pickup, and the process returns to the step of performing a sound source localization operation on the target sound source using a four-element cross microphone array until a preset sound pickup end instruction is received, the target recording file is obtained, and the sound pickup state regulation of the pickup is completed.

2. The method for controlling the pickup state of a variable directional pickup according to claim 1, characterized in that: The four-element cross microphone array includes: a first microphone, a second microphone, a third microphone and a fourth microphone. The positions of the first microphone, the second microphone, the third microphone and the fourth microphone are all located on a circle with the center of gravity of a variable directional microphone as the center. The distances between the first microphone, the second microphone, the third microphone and the fourth microphone and the variable directional microphone are all preset initial distances. The positions of the first microphone and the third microphone are all located on a straight line where the axis of the cylinder of the variable directional microphone is located, and the vertical distance between the first microphone and the upper bottom surface of the cylinder of the variable directional microphone is smaller than the vertical distance between the first microphone and the lower bottom surface of the cylinder of the variable directional microphone, the vertical distance between the third microphone and the lower bottom surface of the cylinder of the variable directional microphone is smaller than the vertical distance between the third microphone and the upper bottom surface of the cylinder of the variable directional microphone, and the straight line where the center of gravity of the second microphone and the center of gravity of the fourth microphone are located is perpendicular to the straight line where the axis of the cylinder of the variable directional microphone is located.

3. The method for controlling the pickup state of a variable directional pickup as claimed in claim 2, characterized in that: The method uses the sound pickup test unit to perform a directional coordinate test on the pre-built test sound pickup to obtain a cardioid coordinate set and a bidirectional coordinate set, including: Fixing the test pickup at the center of the center disk of the pickup test unit to obtain a center pickup, wherein the center pickup is in the shape of a cylinder, and the axis of the cylinder of the center pickup is parallel to the plane where the center disk is located, wherein the modes of the center pickup include: a cardioid directional test mode and a bidirectional test mode; The center of gravity of the central pickup is taken as a pole, and a polar coordinate system is constructed based on the pole, wherein the direction from the center of gravity of the central pickup to the center of the upper bottom surface of the cylinder of the central pickup is taken as the direction of the polar axis of the polar coordinate system; The test position is confirmed based on the polar coordinate system, wherein the test position is located on the outer ring turntable, and the corresponding polar coordinates of the test position in the polar coordinate system are preset initial polar coordinates, wherein the initial polar coordinates are as follows: (ρ0,0°) Among them, ρ0 is the preset initial radius, and the initial radius is larger than the radius of the central disk; Fix the standard sound source at the test position on the outer ring turntable to obtain the test sound source; Set the center pickup mode to the cardioid test mode to obtain the first pickup; The outer ring turntable is rotated clockwise to obtain a rotating turntable, wherein the rotation angular velocity of the outer ring turntable when rotating clockwise is preset, and the target rotation time interval is calculated based on the rotation angular velocity, wherein the calculation formula of the target rotation time interval is as follows: Among them, t w is the target rotation time interval, w0 is the rotation angular velocity; When it is confirmed that the test sound source rotates clockwise with the rotating turntable, the test sound source is started, the time of starting the test sound source is recorded to obtain the start time, and the start time is used as the starting point and the time interval is recorded in real time to obtain the moving time interval; A test sound wave is generated by using the started test sound source, and the test sound wave is collected based on a preset collection frequency and a first pickup. When the moving time interval is equal to the target rotation time interval, a plurality of signal time groups are obtained, wherein the signal time group includes: a test voltage signal and a collection time, wherein the test voltage signal is a voltage signal output when the first pickup collects the test sound wave, and the collection time is the time when the first pickup collects the test sound wave; The following operations are performed for each of the multiple signal time groups: The estimated limit distance is calculated based on the test voltage signal in the signal time group, and the acquisition angle is calculated based on the acquisition time, start time and rotation angular velocity. The calculation formula is as follows: θ x =w0×(t x -t0) Among them, θ x is the acquisition angle, t x is the acquisition time, t0 is the start time; The test polar coordinates are obtained based on the estimated limit distance and acquisition angle, where the test polar coordinates are as follows: (r x ,i x ) Among them, ρ x To estimate the limit distance; Summarize the test polar coordinates to obtain a cardioid coordinate set; Obtain a bidirectional coordinate set based on the center pickup, bidirectional test pattern, outer ring turntable and test sound source.

4. The method for controlling the pickup state of a variable directional pickup as claimed in claim 3, characterized in that: The calculating the estimated limit distance according to the test voltage signal in the signal time group includes: Obtain the fluctuation value of the test voltage signal and calculate the estimated limit distance based on the fluctuation value. The calculation formula is as follows: Among them, ρ x To estimate the limit distance, U m is the fluctuation value, and U0 is the preset standard fluctuation value.

5. The method for controlling the pickup state of a variable directional pickup as claimed in claim 4, characterized in that: The method of constructing a target space coordinate system based on a variable directional microphone and a four-element cross microphone array includes: The center of gravity of the variable directional microphone is taken as the origin of space, and a target space coordinate system is constructed based on the origin of space, wherein the direction from the center of the lower bottom surface of the cylinder of the variable directional microphone to the center of the upper bottom surface of the cylinder of the variable directional microphone is taken as the positive direction of the x-axis of the target space coordinate system, a straight line passing through the origin of space, perpendicular to the x-axis and parallel to the plane where the four-element cross microphone array is located is taken as the y-axis of the target space coordinate system, and a straight line passing through the origin of space, perpendicular to the x-axis and perpendicular to the y-axis is taken as the z-axis of the target space coordinate system.

6. The method for controlling the sound pickup state of a variable directional pickup as claimed in claim 5, characterized in that: The step of respectively identifying the target cardioid space and the target bidirectional space in the target space coordinate system based on the cardioid coordinate set and the bidirectional coordinate set includes: For each test polar coordinate in the cardioid coordinate set, perform the following operations: Confirm the three-dimensional space coordinates based on the estimated limit distance and acquisition angle in the test polar coordinates, where the three-dimensional space coordinates are as follows: (r x ×cosθ x ,r x ×sinθ x ,0) Among them, cos is the cosine function, sin is the sine function; Summarize the three-dimensional space coordinates to obtain multiple three-dimensional space coordinates, and fit the multiple three-dimensional space coordinates in the target space coordinate system to obtain a cardioid curve; The surface enclosed by the cardioid curve and the x-axis of the target space coordinate system is taken as the cardioid surface; In the target space coordinate system, a rotation operation is performed on the cardioid surface using the x-axis of the target space coordinate system as a rotation axis to obtain a target cardioid space, wherein the target cardioid space is a space swept by the cardioid surface during the rotation process; The target bidirectional space is obtained based on the bidirectional coordinate set and the target space coordinate system.

7. The method for controlling the sound pickup state of a variable directional pickup as claimed in claim 6, characterized in that: The method of using a four-element cross microphone array to perform a sound source time difference analysis on a target sound source to obtain a sound transmission time difference of one to two, a sound transmission time difference of one to three, and a sound transmission time difference of one to four includes: confirming a target sound wave based on a target sound source, wherein the target sound wave is a sound wave generated by the target sound source; Turn on the first microphone, the second microphone, the third microphone and the fourth microphone in the four-element cross microphone array, and record the time when the first microphone, the second microphone, the third microphone and the fourth microphone in the four-element cross microphone array are turned on to obtain a starting time, and take the starting time as a starting point and record the time interval in real time to obtain an analysis time interval; The target sound waves are collected by using the first microphone, the second microphone, the third microphone and the fourth microphone respectively after being turned on, until the analysis time interval reaches the preset target time interval, and the first microphone, the second microphone, the third microphone and the fourth microphone are turned off to obtain the first sound signal, the second sound signal, the third sound signal and the fourth sound signal; Determine the midpoint time interval and the quarter time interval based on the target time interval, wherein the midpoint time interval is half of the target time interval and the quarter time interval is one quarter of the target time interval; Confirm the midpoint time based on the start time and the midpoint time interval, wherein the time interval between the midpoint time and the start time is the midpoint time interval, and the midpoint time lags behind the start time; confirm the quarter-minute time based on the start time and the quarter-minute time interval, wherein the time interval between the start time and the quarter-minute time is the quarter-minute time interval, and the quarter-minute time lags behind the start time; confirm the end time based on the midpoint time and the quarter-minute time interval, wherein the time interval between the end time and the midpoint time is the quarter-minute time interval, and the end time lags behind the midpoint time; Determine the time interception range based on the midpoint time and the quarter time, wherein the minimum value of the time interception range is the quarter time and the maximum value of the time interception range is the midpoint time; Intercepting the first sound signal based on the time interception range to obtain a first intercepted signal; Confirming the cutting start time based on the preset cutting time interval and the starting time, wherein the cutting time interval is less than the target time interval, and the time interval between the cutting start time and the starting time is the cutting time interval, and the cutting start time lags behind the starting time; confirming the cutting end time based on the cutting start time and the four-minute time interval, wherein the time interval between the cutting start time and the cutting end time is the four-minute time interval, and the cutting end time lags behind the cutting start time; Acquire a comparison interception range based on the cutting start time and the cutting end time, and perform a signal interception operation on the second sound signal based on the comparison interception range to obtain a second intercepted signal; The unit time difference is calculated according to the cutting end point time and the midpoint time, where the calculation formula of the unit time difference is as follows: T c =t endx -t mid Among them, T c is the unit time difference, t mid is the midpoint time, t endx The cutting end time; Performing a translation operation on the second intercepted signal based on the unit time difference to obtain a second translated signal; The cross-correlation index between the first intercepted signal and the second translated signal is calculated, wherein the calculation formula of the cross-correlation index is as follows: Among them, δ zx is the cross-correlation index, A1(t) is the first intercepted signal, A 2x (t) is the second translation signal, t sk For four minutes; integrating the cross-correlation index and the unit time difference into a correlation data group, storing the correlation data group in a pre-constructed second memory, and obtaining a second target memory; The second target memory is used as the second memory, the cutting start time is used as the starting time, and the process returns to the step of confirming the cutting start time based on the preset cutting time interval and the starting time, until the cutting end time is greater than or equal to the end time, and a plurality of related data groups are extracted from the second target memory; The correlation data group with the largest cross-correlation index among the multiple correlation data groups is recorded as the target data group, and the unit time difference in the target data group is recorded as the one-two time difference of sound transmission; Based on the first intercepted signal, cutting time interval, starting moment, third sound signal and pre-constructed third memory, the sound transmission time difference one-three is obtained; based on the first intercepted signal, cutting time interval, starting moment, fourth sound signal and pre-constructed fourth memory, the sound transmission time difference one-four is obtained.

8. The method for controlling the pickup state of a variable directional pickup as claimed in claim 7, characterized in that: The method of performing a mode correction operation on the variable directional microphone based on the target sound source point, the target cardioid space and the target bidirectional space to obtain the target microphone includes: Determine whether the target sound source point is located in the target cardioid space, and if the target sound source point is located in the target cardioid space, set the mode of the variable directional microphone to a cardioid directional mode to obtain a cardioid microphone; If the target sound source point is not located in the target cardioid space, it is determined whether the target sound source point is located in the target bidirectional space; if the target sound source point is located in the target bidirectional space, the mode of the variable directional microphone is set to a bidirectional mode to obtain a bidirectional microphone; otherwise, the mode of the variable directional microphone is set to an omnidirectional mode to obtain an omnidirectional microphone; The cardioid pickup, the bidirectional pickup or the omnidirectional pickup is recorded as a target pickup.

9. A sound pickup state control system for a variable directional pickup, characterized in that: The system comprises: A sound pickup direction test module is used to confirm the sound pickup test unit, wherein the sound pickup test unit includes: a soundproof room, a standard sound source and a layered turntable, the layered turntable includes a central disk and an outer turntable, wherein the standard sound source and the layered turntable are both located in the soundproof room, and the outer turntable surrounds the central disk. The sound pickup test unit is used to perform a direction coordinate test on the pre-built test pickup to obtain a cardioid coordinate set and a bidirectional coordinate set; A sound pickup space confirmation module is used to receive a sound control instruction, and confirm a sound control environment based on the sound control instruction, wherein the sound control environment includes: a target sound source, a variable directional sound pickup, and a four-element cross microphone array, wherein the variable directional sound pickup is in the shape of a cylinder, a target space coordinate system is constructed based on the variable directional sound pickup and the four-element cross microphone array, and a target cardioid space and a target bidirectional space are confirmed in the target space coordinate system based on a cardioid coordinate set and a bidirectional coordinate set respectively; The sound pickup mode correction module is used to start the variable directional sound pickup, use the started variable directional sound pickup to pick up the target sound source in the sound control environment in real time, take the time when the variable directional sound pickup is started as the starting point and record the time interval in real time to obtain the sound pickup time interval, use the four-element cross microphone array to perform sound source time difference analysis on the target sound source, and obtain the sound transmission one-two time difference, the sound transmission one-three time difference and the sound transmission one-four time difference; The three-dimensional coordinates of the sound source are calculated according to the one-two time difference, the one-three time difference and the one-four time difference of sound transmission, wherein the three-dimensional coordinates of the sound source are calculated according to the one-two time difference, the one-three time difference and the one-four time difference of sound transmission, including: The distance of the sound source is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows: Among them, D sx is the distance from the sound source, v s is the preset sound speed, T 12 , T 13 and T 14 They are the sound transmission time difference of one and two, the sound transmission time difference of one and three, and the sound transmission time difference of one and four; The plane angle is calculated based on the time difference of one to two, the time difference of one to three, and the time difference of one to four. The calculation formula is as follows: Among them, α x is the plane angle, arctan is the inverse tangent function; The altitude angle is calculated based on the time difference of one to two, the time difference of one to three, the time difference of one to four and the initial distance. The calculation formula is as follows: Among them, β x is the altitude angle, arcsin is the inverse sine function, D x0 is the initial distance; The three-dimensional coordinates of the sound source are obtained according to the sound source distance, plane angle and altitude angle, where the three-dimensional coordinates of the sound source are as follows: (D sx ×sinβ x ×cosα x ,D sx ×sinα x ×sinβ x ,D sx ×cosβ x ) Among them, sin is the sine function and cos is the cosine function; Based on the three-dimensional coordinates of the sound source, a target sound source point is identified in a target space coordinate system, and a mode correction operation is performed on a variable directional microphone based on the target sound source point, a target cardioid space, and a target bidirectional space to obtain a target microphone, wherein the modes of the variable directional microphone include: a cardioid directional mode, a bidirectional mode, and an omnidirectional mode; The sound pickup step loop module is used to, when the sound pickup time interval reaches a preset sound pickup threshold, take the time when the sound pickup time interval reaches the preset sound pickup threshold as the starting point and record the time interval in real time, obtain an updated time interval, use the updated time interval as the sound pickup time interval, use the target pickup as a variable directional pickup, and return to the step of performing a sound source localization operation on the target sound source using a four-element cross microphone array until a preset sound pickup end instruction is received, obtain a target recording file, and complete the sound pickup state regulation of the pickup.

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