Spatial noise reduction method, device, equipment and storage medium based on lecture hall

Abstract

The present invention relates to a spatial noise reduction technology, and discloses a spatial noise reduction method based on a stepped classroom, comprising: performing similarity recognition on a sound signal and an input signal respectively obtained by a main microphone and a noise reducer of the stepped classroom, and deleting similar signals in the input signal according to the result of the similarity recognition to obtain a noise signal; calculating a resonance frequency according to the three-dimensional information of the stepped classroom, and calculating a control noise signal according to the resonance frequency and a noise suppression algorithm; filtering the noise signal according to a proportional coefficient determined by the control noise signal and the spatial position of the noise reducer to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to a speaker. The present invention also proposes a spatial noise reduction device, an electronic device, and a storage medium based on a stepped classroom. The present invention can improve the noise reduction effect and the accurate noise reduction of the noise field under mixed content.

Description

Technical Field

[0001] The present invention relates to the field of spatial noise reduction technology, and in particular to a spatial noise reduction method, device, electronic device and computer-readable storage medium based on a stepped classroom. Background Art

[0002] With the development of science and technology and the improvement of people's living standards, noise is an inevitable part of daily work, study and life. Therefore, the technology of using science and technology to achieve active noise reduction has emerged. Active noise reduction is to offset external noise by generating reverse sound waves equal to external noise through the noise reduction system. In the field of noise reduction, the problem of spatial noise reduction is particularly prominent. In application scenarios such as lecture halls and conference rooms, the combination of spatial noise reduction and conference voice makes noise reduction more difficult.

[0003] At present, the active spatial noise reduction system in the prior art is usually composed of a single microphone and a single speaker. After the microphone picks up the noise, it can only send out an anti-phase sound wave with a phase opposite to the noise through one speaker to cancel the noise; or measure the noise signal through each noise sampling point, use a filter circuit to process each noise signal to generate a noise reduction signal, and determine the noise reduction result based on the average value of the processed sound signal at each sampling point. However, due to the complexity of the noise in the spatial field, the noise reduction effect achieved by the prior art is poor, and it is impossible to achieve accurate noise reduction for the noise field under mixed content. Summary of the invention

[0004] The present invention provides a spatial noise reduction method, device and computer-readable storage medium based on a stepped classroom, the main purpose of which is to solve the problem of poor noise reduction effect and inability to accurately reduce the noise field under mixed content.

[0005] To achieve the above object, the present invention provides a spatial noise reduction method based on a stepped classroom, comprising:

[0006] Receiving a sound signal from a main microphone of a lecture hall, and collecting input signals from a plurality of preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone, and a speaker;

[0007] Performing similarity recognition on the sound signal and the input signal, and deleting similar signals in the input signal according to the result of the similarity recognition to obtain a noise signal;

[0008] Acquire three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, determine the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm;

[0009] Filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to the speaker for output;

[0010] Using the second microphone to collect the residual noise signal remaining after the speaker outputs the sound signal and the anti-phase noise signal, and determining whether the remaining residual noise signal is less than a stepped classroom noise threshold;

[0011] If the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

[0012] Optionally, the performing similarity recognition on the sound signal and the input signal, and deleting a similar signal in the input signal according to a result of the similarity recognition to obtain a noise signal, includes:

[0013] Extracting the sound digital discreteness of the sound signal and the input signal respectively, and performing consistency comparison according to the sound digital discreteness;

[0014] When the consistency comparison result of the sound digital discreteness is greater than a preset threshold, an input signal corresponding to the sound digital discreteness greater than the preset threshold is extracted as a target signal, and the target signal is deleted from the input signal.

[0015] Optionally, determining a proportional coefficient corresponding to the noise reducer according to a spatial position of the noise reducer in the lecture hall includes:

[0016] Obtaining the standing wave sound field distribution of the stepped classroom to obtain a three-dimensional closed standing wave sound field;

[0017] Determining the acoustic mode anti-interface position according to the three-dimensional closed standing wave acoustic field;

[0018] Determine a first weight according to the step height in the spatial position, and obtain a second weight according to the correspondence between the acoustic mode anti-interface position and the spatial position of the noise reducer;

[0019] A proportional coefficient corresponding to the noise reducer is calculated according to the first weight and the weight.

[0020] Optionally, the calculating the control noise signal corresponding to the noise signal according to the resonant frequency and a preset noise suppression algorithm includes:

[0021] Acquire a target noise signal contained in the noise signal having the same frequency as the resonance frequency;

[0022] Calculating the target noise signal using a preset FxLMS algorithm to obtain a target control noise signal;

[0023] The target control noise signal is integrated with noise signals other than the target noise signal in the noise signal to obtain a control noise signal.

[0024] Optionally, filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain the anti-phase noise signal includes:

[0025] Converting the reference noise signal and the residual noise signal into a first digital signal and a second digital signal through an AD converter;

[0026] A preset filtering formula is used to calculate according to the first digital signal, the second digital signal and the proportional coefficient to obtain an anti-phase noise signal.

[0027] Optionally, the using a preset filtering formula to calculate according to the first digital signal, the second digital signal and the proportional coefficient to obtain the anti-phase noise signal includes:

[0028] Calculate the first digital signal according to a first formula in the filtering formula to obtain a first filtering result;

[0029] updating a preset filtering coefficient according to the first filtering result, the second digital signal and the proportional coefficient;

[0030] The updated filter coefficient and the first filter result are calculated according to the second formula in the filter formula to obtain an inverted noise signal.

[0031] Optionally, transmitting the sound signal and the anti-phase noise signal to the speaker for output includes:

[0032] Performing signal integration on the sound signal and the anti-phase noise signal;

[0033] The integrated signal is converted into an analog signal through an audio DAC, and the analog signal is pre-amplified;

[0034] The loudspeaker is used to output the pre-amplified analog signal to the lecture hall.

[0035] In order to solve the above problems, the present invention also provides a spatial noise reduction device based on a stepped classroom, the device comprising:

[0036] A multiple signal acquisition module, used to receive the sound signal of the main microphone of the lecture hall, and to collect the input signals of multiple preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone and a speaker;

[0037] A noise signal generating module, used for performing similarity recognition between the sound signal and the input signal, and deleting a similar signal in the input signal according to a result of the similarity recognition to obtain a noise signal;

[0038] A control noise signal generation module is used to obtain three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm;

[0039] an inverted noise signal generating module, for determining a proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to the speaker for output;

[0040] The noise reprocessing module is used to use the second microphone to collect the residual noise signal remaining after the speaker outputs the sound signal and the anti-phase noise signal, and determine whether the remaining residual noise signal is less than the stepped classroom noise threshold; if the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to filter the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

[0041] In order to solve the above problem, the present invention further provides an electronic device, the electronic device comprising:

[0042] at least one processor; and,

[0043] a memory communicatively connected to the at least one processor; wherein,

[0044] The memory stores a computer program that can be executed by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the above-mentioned spatial noise reduction method based on the stepped classroom.

[0045] In order to solve the above problems, the present invention also provides a computer-readable storage medium, in which at least one computer program is stored. The at least one computer program is executed by a processor in an electronic device to implement the above-mentioned spatial noise reduction method based on a stepped classroom.

[0046] The embodiment of the present invention performs similarity recognition based on the sound signal of the main microphone and the input signal to ensure the distinction between the target propagation content and the noise content in the application scenario with mixed content, and ensures that only the noise signal is suppressed when performing spatial noise suppression, thereby avoiding weakening the useful sound signal in the noise suppression process, and achieving accurate noise reduction of the noise field; by filtering and updating the filter coefficient according to the noise signal and the spatial position of the noise reducer, the complexity of the noise in the spatial field and the distribution of the noise reducer in the space are taken into account, and efficient noise reduction for noise in different spatial positions is achieved; by collecting the residual noise signal remaining after the speaker outputs the sound signal and the inverted noise signal, the subsequent noise reduction situation is further confirmed to improve the final noise reduction effect. Therefore, the spatial noise reduction method, device, electronic device and computer-readable storage medium based on the stepped classroom proposed by the present invention can solve the problem of poor noise reduction effect and inability to accurately reduce the noise field under mixed content. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 A schematic diagram of a flow chart of a spatial noise reduction method based on a lecture hall provided in one embodiment of the present invention;

[0048] Figure 2 A schematic diagram of a flow chart of determining a proportional coefficient corresponding to a noise reducer according to a spatial position of the noise reducer provided in one embodiment of the present invention;

[0049] Figure 3 A schematic diagram of a flow chart of calculating a noise signal according to a resonance frequency and a preset noise suppression algorithm provided in one embodiment of the present invention;

[0050] Figure 4 A functional module diagram of a spatial noise reduction device based on a lecture hall provided by an embodiment of the present invention;

[0051] Figure 5 A schematic diagram of the structure of an electronic device for implementing the spatial noise reduction method based on a stepped classroom provided in one embodiment of the present invention.

[0052] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0053] 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.

[0054] The embodiment of the present application provides a spatial noise reduction method based on a stepped classroom. The execution subject of the spatial noise reduction method based on the stepped classroom includes but is not limited to at least one of the electronic devices such as a server, a terminal, etc. that can be configured to execute the method provided by the embodiment of the present application. In other words, the spatial noise reduction method based on the stepped classroom 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. The server can be an independent server, or it can be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery networks (Content Delivery Network, CDN), and big data and artificial intelligence platforms.

[0055] Reference Figure 1 FIG. 1 is a flow chart of a spatial noise reduction method based on a stepped classroom provided by an embodiment of the present invention. In this embodiment, the spatial noise reduction method based on a stepped classroom includes:

[0056] S1. Receive a sound signal from a main microphone in a lecture hall, and collect input signals from a plurality of preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone, and a speaker.

[0057] In an embodiment of the present invention, the sound signal of the main microphone may be a sound signal emitted by a speaker through a speech microphone in a preset tiered classroom or conference room; the input signal of the noise reducer may include a reference noise signal of the first microphone, a residual noise signal of the second microphone, etc.

[0058] The embodiment of the present invention can actively collect the sound signal of the main microphone and the input signal of the noise reducer through the microphone and the noise reducer installed in the area such as the wall of the space.

[0059] In an embodiment of the present invention, a plurality of noise reducers may be fixedly arranged on the inner surface of a preset stepped classroom or conference room. The noise reducers may be distributed at equal intervals or at non-equal intervals. For example, one noise reducer may be installed per square meter. The first microphone, the second microphone, and the speaker in the noise reducer may be spaced at a certain distance in a direction perpendicular to the spatial position, so as to reduce mutual interference between the three, or they may be regularly distributed according to their actual uses to form a noise reducer unit. Multiple noise reducers may be distributed on the inner surface of a single wall, on the inner surfaces of multiple walls, or on the outer walls of the space.

[0060] S2. Perform similarity recognition on the sound signal and the input signal, and delete similar signals in the input signal according to the result of the similarity recognition to obtain a noise signal.

[0061] The embodiment of the present invention deletes the input signal through the similarity recognition result of the sound signal, thereby suppressing only the noise signal, thereby ensuring that the sound signal of the main microphone in the lecture hall is transmitted without being disturbed by noise.

[0062] In the embodiment of the present invention, the performing similarity recognition on the sound signal and the input signal, and deleting the similar signal in the input signal according to the result of the similarity recognition to obtain the noise signal includes:

[0063] Extracting the sound digital discreteness of the sound signal and the input signal respectively, and performing consistency comparison according to the sound digital discreteness;

[0064] When the consistency comparison result of the sound digital discreteness is greater than a preset threshold, an input signal corresponding to the sound digital discreteness greater than the preset threshold is extracted as a target signal, and the target signal is deleted from the input signal.

[0065] For example, when the consistency comparison result is greater than 85%, it can be determined that the input signal includes a signal corresponding to the sound signal, and the signal corresponding to the sound signal is subtracted from the signal corresponding to the input signal, and the resulting signal is the noise signal.

[0066] S3. Acquire three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, determine the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm.

[0067] In an embodiment of the present invention, the three-dimensional size information of the lecture hall can be obtained by the spatial information acquisition component, and the three-dimensional size information includes length, width and height; the proportional coefficient is the proportional coefficient determined by the positional relationship of the noise reducer relative to the lecture hall.

[0068] Specifically, the resonant frequency of the lecture hall can be calculated according to the following calculation formula and three-dimensional information:

[0069]

[0070] in, is the resonant frequency, The three-dimensional size information is length, width and height respectively. is the speed of sound, is the preset modal coefficient, and its value range is a natural number.

[0071] In the embodiment of the present invention, due to the influence that the floor of the lecture hall gradually rises in a stepped shape, the length in the three-dimensional information may be the length of the inclined ground.

[0072] For example, The value of can be 1 or 2 respectively. The combination can calculate 8 results, among which there may be results with the same value. That is, a maximum of 8 resonance frequency information can be obtained through the above formula.

[0073] See also Figure 2 As shown, in the embodiment of the present invention, determining the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall includes:

[0074] S21, obtaining the standing wave sound field distribution of the stepped classroom to obtain a three-dimensional closed standing wave sound field;

[0075] S22, determining the acoustic mode anti-interface position according to the three-dimensional closed standing wave sound field;

[0076] S23, determining a first weight according to the step height in the spatial position, and obtaining a second weight according to the correspondence between the acoustic mode anti-interface position and the spatial position of the noise reducer;

[0077] S24. Calculate a proportional coefficient corresponding to the noise reducer according to the first weight and the weight.

[0078] In an embodiment of the present invention, the standing wave sound field distribution of the stepped classroom is affected by the gradual rise of the floor of the stepped classroom in a stepped shape. The farther away from the podium, the higher the ground. The standing waves in the front part of the stepped classroom close to the podium and the back part of the space far away from the podium are different; and because the steps continue to rise, the proportional weights corresponding to the noise reducers at different step heights are different.

[0079] The embodiment of the present invention can obtain the standing wave sound field distribution of the stepped classroom through active noise control theoretical analysis; the acoustic mode anti-interface position is obtained from the standing wave sound field, that is, the position condition satisfied when the detected secondary sound source intensity is equal to the optimal secondary sound source intensity.

[0080] See also Figure 3 As shown, in the embodiment of the present invention, the control noise signal corresponding to the noise signal is calculated according to the resonant frequency and a preset noise suppression algorithm, including:

[0081] S31, obtaining a target noise signal contained in the noise signal and having the same frequency as the resonance frequency;

[0082] S32, calculating the target noise signal using a preset FxLMS algorithm to obtain a target control noise signal;

[0083] S33: Integrate the target control noise signal with the noise signals other than the target noise signal in the noise signal to obtain a control noise signal.

[0084] In the embodiment of the present invention, by controlling the noise signal to include a target noise signal having the same frequency as the resonance frequency, the occurrence of sound resonance in the lecture hall is avoided, thereby improving the control effect of noise reduction in the lecture hall.

[0085] In another optional embodiment of the present invention, after generating the control noise signal, the method further includes:

[0086] Extracting the acoustic wave characteristics of the control noise signal;

[0087] generating a reverse acoustic wave feature according to the acoustic wave feature;

[0088] The reverse acoustic wave characteristics are synthesized to obtain an anti-phase noise signal.

[0089] In the embodiment of the present invention, the acoustic wave characteristics include but are not limited to spectrum characteristics and phase characteristics.

[0090] S4. Filter the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmit the sound signal and the inverted noise signal to the speaker for output.

[0091] In an embodiment of the present invention, filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain the anti-phase noise signal includes:

[0092] Converting the reference noise signal and the residual noise signal into a first digital signal and a second digital signal through an AD converter;

[0093] A preset filtering formula is used to calculate according to the first digital signal, the second digital signal and the proportional coefficient to obtain an anti-phase noise signal.

[0094] Furthermore, the use of a preset filtering formula to calculate according to the first digital signal, the second digital signal and the proportional coefficient to obtain an anti-phase noise signal includes:

[0095] Calculate the first digital signal according to a first formula in the filtering formula to obtain a first filtering result;

[0096] updating a preset filtering coefficient according to the first filtering result, the second digital signal and the proportional coefficient;

[0097] The updated filter coefficient and the first filter result are calculated according to the second formula in the filter formula to obtain an inverted noise signal.

[0098] Specifically, the first digital signal may be calculated using the following first formula:

[0099]

[0100] in, For the The first filtering result of the denoiser, For the The preset filter coefficients of the denoiser, For the The first digital signal of the noise reducer, Represents the convolution operation;

[0101] The preset filter coefficient can be updated using the following formula:

[0102]

[0103] in, is the updated filter coefficient, For the The scaling factor of the noise reducer, is the preset learning step size, For the a second digital signal of a noise reducer, and The vectors have the same length;

[0104] The updated filter coefficient and the first filter result can be calculated using the following second formula:

[0105]

[0106] in, For the The anti-phase noise signal of the noise reducer, For the The first filtering result output by the noise reducer.

[0107] In the embodiment of the present invention, the first formula in the filtering formula can be implemented by calculating the first filter in the noise reducer, and the second formula in the filtering formula can be implemented by calculating the second filter in the noise reducer.

[0108] In an embodiment of the present invention, in the first filtering, the residual noise signal corresponding to the error microphone in the noise reducer is filtered according to the filtering coefficient to obtain a corrected residual noise signal. The purpose of the first filtering is to reasonably distribute the residual noise processed by each noise reducer; in the second filtering, the reference noise signal picked up by the reference microphone in the noise reducer is filtered according to the updated filtering coefficient to obtain an inverted noise signal for playback by the speaker in any one of the noise reducers. The goal of the second filtering is for each noise reducer to output the corresponding inverted noise according to its respective assigned residual noise intensity.

[0109] In the embodiment of the present invention, the step of transmitting the sound signal and the anti-phase noise signal to the speaker for output includes:

[0110] Performing signal integration on the sound signal and the anti-phase noise signal;

[0111] The integrated signal is converted into an analog signal through an audio DAC, and the analog signal is pre-amplified;

[0112] The loudspeaker is used to output the pre-amplified analog signal to the lecture hall.

[0113] S5. Using the second microphone to collect the residual noise signal remaining after the speaker outputs the sound signal and the anti-phase noise signal, and determining whether the remaining residual noise signal is less than a stepped classroom noise threshold.

[0114] In the embodiment of the present invention, after the speaker outputs the anti-phase noise signal, the second microphone can be used to actively collect the residual noise signal, thereby obtaining the remaining residual noise signal.

[0115] In an embodiment of the present invention, the obtained remaining residual noise signal is compared with the noise threshold of the lecture hall, thereby achieving an intuitive judgment on the noise reduction result, wherein the spatial noise threshold can be set to different values ​​according to the standards of different lecture halls and conference rooms.

[0116] If the remaining residual noise signal is greater than or equal to the spatial noise threshold, the process returns to S4.

[0117] In an embodiment of the present invention, if the remaining residual noise signal is smaller than the spatial noise threshold, it means that the noise reduction achieved in the above steps does not meet the preset requirements and does not meet the indoor noise requirements. The process can return to step S4 and perform noise reduction again according to the remaining residual noise signal to generate a new inverted noise signal and transmit it to the speaker to achieve spatial noise reduction again.

[0118] If the remaining residual noise signal is smaller than the spatial noise threshold, step S6 is performed and the spatial noise reduction process ends.

[0119] In the embodiment of the present invention, if the remaining residual noise signal is smaller than the spatial noise threshold, it means that the noise reduction achieved by the above steps meets the preset requirements and the indoor noise requirements, and there is no need to perform spatial noise reduction processing again.

[0120] The embodiment of the present invention performs similarity recognition based on the sound signal of the main microphone and the input signal to ensure the distinction between the target propagation content and the noise content in the application scenario with mixed content, and ensures that only the noise signal is suppressed when performing spatial noise suppression, thereby avoiding weakening the useful sound signal in the noise suppression process, and achieving accurate noise reduction of the noise field; by filtering and updating the filter coefficient according to the noise signal and the spatial position of the noise reducer, the complexity of the noise in the spatial field and the distribution of the noise reducer in the space are taken into account, and efficient noise reduction for noise in different spatial positions is achieved; by collecting the residual noise signal remaining after the speaker outputs the sound signal and the inverted noise signal, the subsequent noise reduction situation is further confirmed to improve the final noise reduction effect. Therefore, the spatial noise reduction method based on the stepped classroom proposed by the present invention can solve the problems of poor noise reduction effect and inability to accurately reduce the noise field under mixed content.

[0121] like Figure 4 , which is a functional module diagram of a spatial noise reduction device based on a stepped classroom provided by an embodiment of the present invention.

[0122] The spatial noise reduction device 100 based on a stepped classroom of the present invention can be installed in an electronic device. According to the functions to be implemented, the spatial noise reduction device 100 based on a stepped classroom can include a multiple signal acquisition module 101, a noise signal generation module 102, a control noise signal generation module 103, an inverted noise signal generation module 104 and a noise reprocessing module 105. The module of the present invention can also be referred to as a unit, which refers to a series of computer program segments that can be executed by a processor of an electronic device and can complete fixed functions, which are stored in the memory of the electronic device.

[0123] In this embodiment, the functions of each module / unit are as follows:

[0124] The multiple signal acquisition module 101 is used to receive the sound signal of the main microphone of the lecture hall and to collect the input signals of multiple preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone and a speaker;

[0125] The noise signal generating module 102 is used to perform similarity recognition between the sound signal and the input signal, and delete the similar signal in the input signal according to the result of the similarity recognition to obtain the noise signal;

[0126] The control noise signal generating module 103 is used to obtain three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm;

[0127] The anti-phase noise signal generating module 104 is used to determine the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, filter the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an anti-phase noise signal, and transmit the sound signal and the anti-phase noise signal to the speaker for output;

[0128] The noise reprocessing module 105 is used to use the second microphone to collect the residual noise signal remaining after the speaker outputs the sound signal and the anti-phase noise signal, and determine whether the remaining residual noise signal is less than the stepped classroom noise threshold; if the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to filter the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

[0129] In detail, each module described in the spatial noise reduction device 100 based on the stepped classroom in the embodiment of the present invention is used in the same manner as described above. Figures 1 to 3 The same technical means are used as the spatial noise reduction method based on the stepped classroom described in, and can produce the same technical effects, so I will not go into details here.

[0130] like Figure 5 , which is a schematic diagram of the structure of an electronic device for implementing a spatial noise reduction method based on a stepped classroom provided by an embodiment of the present invention.

[0131] The electronic device 1 may include a processor 10, a memory 11, a communication bus 12, and a communication interface 13, and may also include a computer program stored in the memory 11 and executable on the processor 10, such as a spatial noise reduction program based on a lecture hall.

[0132] In some embodiments, the processor 10 may be composed of an integrated circuit, 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. The processor 10 is the control core (ControlUnit) 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 (for example, executing a spatial noise reduction program based on a lecture hall, etc.), and calls data stored in the memory 11 to execute various functions of the electronic device and process data.

[0133] 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 (for example, 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 an electronic device, such as a mobile hard disk of the electronic device. In other embodiments, the memory 11 may also be an external storage device of an electronic device, such as a plug-in mobile hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), etc. equipped on the electronic device. Further, the memory 11 may also include both an internal storage unit of the electronic device 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, such as the code of the spatial noise reduction program based on the stepped classroom, but also can be used to temporarily store data that has been output or is to be output.

[0134] The communication bus 12 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The bus is configured to realize connection and communication between the memory 11 and at least one processor 10, etc.

[0135] The communication interface 13 is used for communication between the above-mentioned electronic device and other devices, including a network interface and a user 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 and other electronic devices. The user interface may be a display (Display), an input unit (such as a keyboard (Keyboard)), and optionally, the user interface may also be a standard wired interface, 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, organic light-emitting diode) touch device, etc. Among them, 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 and to display a visual user interface.

[0136] Figure 5 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 5 The 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.

[0137] For example, although not shown, the electronic device 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 may also include a variety of sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

[0138] It should be understood that the embodiment is for illustration only and the scope of the patent application is not limited to this structure.

[0139] The spatial noise reduction program based on the lecture hall stored in the memory 11 of the electronic device 1 is a combination of multiple instructions. When running in the processor 10, it can achieve:

[0140] Receiving a sound signal from a main microphone of a lecture hall, and collecting input signals from a plurality of preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone, and a speaker;

[0141] Performing similarity recognition on the sound signal and the input signal, and deleting similar signals in the input signal according to the result of the similarity recognition to obtain a noise signal;

[0142] Acquire three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, determine the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm;

[0143] Filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to the speaker for output;

[0144] Using the second microphone to collect the residual noise signal remaining after the speaker outputs the sound signal and the anti-phase noise signal, and determining whether the remaining residual noise signal is less than a stepped classroom noise threshold;

[0145] If the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

[0146] Specifically, the specific implementation method of the processor 10 for the above instructions can refer to the description of the relevant steps in the corresponding embodiment of the accompanying drawings, which will not be repeated here.

[0147] 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).

[0148] 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:

[0149] Receiving a sound signal from a main microphone of a lecture hall, and collecting input signals from a plurality of preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone, and a speaker;

[0150] Performing similarity recognition on the sound signal and the input signal, and deleting similar signals in the input signal according to the result of the similarity recognition to obtain a noise signal;

[0151] Acquire three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, determine the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm;

[0152] Filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to the speaker for output;

[0153] Using the second microphone to collect the residual noise signal remaining after the speaker outputs the sound signal and the anti-phase noise signal, and determining whether the remaining residual noise signal is less than a stepped classroom noise threshold;

[0154] If the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

[0155] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, so it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any attached figure mark in the claims should not be regarded as limiting the claims involved.

[0160] In addition, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Multiple units or devices stated in the system claim can also be implemented by one unit or device through software or hardware. The words first, second, etc. are used to indicate names, and do not indicate any particular order.

[0161] 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 spatial noise reduction method based on a lecture hall. It is characterized in that The method comprises: Receiving a sound signal from a main microphone of a lecture hall, and collecting input signals from a plurality of preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone, and a speaker; Performing similarity recognition on the sound signal and the input signal, and deleting a similar signal in the input signal according to a result of the similarity recognition to obtain a noise signal; Acquire three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, determine the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm; Filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to the speaker for output to obtain a noise-reduced sound signal; collecting, using the second microphone, a residual noise signal remaining after the speaker outputs the noise-reduced sound signal, and determining whether the remaining residual noise signal is less than a spatial noise threshold; If the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to the step of filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

2. The spatial noise reduction method based on a stepped classroom as claimed in claim 1, It is characterized in that The performing similarity identification on the sound signal and the input signal, and deleting similar signals in the input signal according to the result of the similarity identification to obtain a noise signal, includes: Extracting the sound digital discreteness of the sound signal and the input signal respectively, and performing consistency comparison according to the sound digital discreteness; When the consistency comparison result of the sound digital discreteness is greater than a preset threshold, an input signal corresponding to the sound digital discreteness greater than the preset threshold is extracted as a target signal, and the target signal is deleted from the input signal.

3. The spatial noise reduction method based on a stepped classroom as claimed in claim 1, It is characterized in that Determining the proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall includes: Obtaining the standing wave sound field distribution of the stepped classroom to obtain a three-dimensional closed standing wave sound field; Determining the acoustic mode anti-interface position according to the three-dimensional closed standing wave acoustic field; Determine a first weight according to the step height in the spatial position, and obtain a second weight according to the correspondence between the acoustic mode anti-interface position and the spatial position of the noise reducer; A proportional coefficient corresponding to the noise reducer is calculated according to the first weight and the weight.

4. The spatial noise reduction method based on a stepped classroom as claimed in claim 1, It is characterized in that The step of calculating the control noise signal corresponding to the noise signal according to the resonant frequency and a preset noise suppression algorithm includes: Acquire a target noise signal contained in the noise signal having the same frequency as the resonance frequency; Calculating the target noise signal using a preset FxLMS algorithm to obtain a target control noise signal; The target control noise signal is integrated with noise signals other than the target noise signal in the noise signal to obtain a control noise signal.

5. The spatial noise reduction method based on a stepped classroom as claimed in claim 1, It is characterized in that The filtering process is performed on the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an anti-phase noise signal, including: Converting the reference noise signal and the residual noise signal into a first digital signal and a second digital signal through an AD converter; A preset filtering formula is used to calculate according to the first digital signal, the second digital signal and the proportional coefficient to obtain an anti-phase noise signal.

6. The spatial noise reduction method based on a stepped classroom as claimed in claim 5, It is characterized in that The using a preset filtering formula to calculate according to the first digital signal, the second digital signal and the proportional coefficient to obtain an anti-phase noise signal includes: Calculate the first digital signal according to a first formula in the filtering formula to obtain a first filtering result; updating a preset filtering coefficient according to the first filtering result, the second digital signal and the proportional coefficient; The updated filter coefficient and the first filter result are calculated according to the second formula in the filter formula to obtain an inverted noise signal.

7. The spatial noise reduction method based on a lecture hall according to any one of claims 1 to 6, It is characterized in that The step of transmitting the sound signal and the anti-phase noise signal to the speaker for output includes: Performing signal integration on the sound signal and the anti-phase noise signal; The integrated signal is converted into an analog signal through an audio DAC, and the analog signal is pre-amplified; The loudspeaker is used to output the pre-amplified analog signal to the lecture hall.

8. A spatial noise reduction device based on a stepped classroom. It is characterized in that The device comprises: A multiple signal acquisition module, used to receive the sound signal of the main microphone of the lecture hall, and to collect the input signals of multiple preset noise reducers in the lecture hall, wherein the noise reducers include a first microphone, a second microphone and a speaker; A noise signal generating module, used for performing similarity recognition between the sound signal and the input signal, and deleting a similar signal in the input signal according to a result of the similarity recognition to obtain a noise signal; A control noise signal generation module is used to obtain three-dimensional information of the lecture hall, calculate the resonance frequency according to the three-dimensional information, and calculate the control noise signal corresponding to the noise signal according to the resonance frequency and a preset noise suppression algorithm; an inverted noise signal generating module, for determining a proportional coefficient corresponding to the noise reducer according to the spatial position of the noise reducer in the lecture hall, filtering the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal to obtain an inverted noise signal, and transmitting the sound signal and the inverted noise signal to the speaker for output to obtain a noise-reduced sound signal; A noise reprocessing module is used to use the second microphone to collect the residual noise signal remaining after the speaker outputs the noise-reduced sound signal, and determine whether the remaining residual noise signal is less than a spatial noise threshold; if the remaining residual noise signal is greater than or equal to the spatial noise threshold, return to filter the control noise signal according to the reference noise signal of the first microphone, the residual noise signal of the second microphone and the proportional coefficient in the control noise signal until the remaining residual noise signal is less than the spatial noise threshold.

9. An electronic device, It is characterized in that The electronic device comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the spatial noise reduction method based on a lecture hall as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, It is characterized in that When the computer program is executed by a processor, the spatial noise reduction method based on a lecture hall as described in any one of claims 1 to 7 is implemented.

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