An intelligent sound amplification system for teaching sound amplification

Abstract

The invention discloses an intelligent sound amplification system for teaching sound amplification, and relates to the technical field of sound amplification systems. In the process of sound amplification, a microphone monitoring module monitors the harmonic distortion and signal-to-noise ratio of a microphone on a lectern and a microphone suspended on the top of a podium within a period of time, and generates a sound capture score for the microphone on the lectern and the microphone suspended on the top of a podium after preprocessing the harmonic distortion and the signal-to-noise ratio. The abnormal state of the microphone on the lectern and the microphone suspended on the top of the podium is determined by comparing the sound capture score with a score threshold. The control prompt module uses fuzzy logic to determine whether to send a voice prompt to the teacher's earphone and control the operation of the microphone according to the abnormal state and the teacher's trend. The sound amplification system can provide corresponding voice prompts and control the microphone to the teacher in combination with the teacher's trend and the operating state of the microphone in use, which not only reduces the overall energy consumption of the sound amplification system, but also effectively ensures the stable use of the sound amplification system.

Description

Technical Field

[0001] The present invention relates to the technical field of sound amplification systems, and in particular to an intelligent sound amplification system for teaching sound amplification. Background Art

[0002] In the past, teachers often suffered from pharyngitis due to irritation from chalk dust or excessive use of their throats. With the change of teaching methods, most teachers no longer need to use chalk on the blackboard when teaching, but the incidence of pharyngitis among teachers is still high. This is mainly related to the pronunciation method and the lack of sound amplification products. Data show that on average, teachers speak for 6.5 hours a day; on average, 20% of teachers are absent for a week each school year due to throat problems, and 21% of teachers insist on teaching despite having a sore throat. The risk of throat-related diseases in the teaching profession is 32 times greater than that of other ordinary professions. In order to reduce the incidence of pharyngitis, schools usually equip teachers with sound amplification equipment.

[0003] The prior art has the following deficiencies:

[0004] In order to improve the sound amplification effect of the sound reinforcement system, the existing sound reinforcement system is usually equipped with multiple microphones for auxiliary use. However, in the actual operation process, the sound reinforcement system is unable to obtain the teacher's movements and secondly, it has no usage status monitoring of the microphone in operation. Therefore, it is impossible to combine the teacher's movements and the microphone usage status to provide voice prompts to the teacher and control the microphone. This not only increases the overall energy consumption of the sound reinforcement system, but also fails to ensure the stable operation of the sound reinforcement system. Summary of the invention

[0005] The purpose of the present invention is to provide an intelligent sound amplification system for teaching sound amplification to solve the shortcomings of the background technology.

[0006] In order to achieve the above-mentioned object, the present invention provides the following technical solutions: an intelligent sound amplification system for teaching sound amplification, comprising a judgment color acquisition module, a shielding sound amplification module, a teacher movement judgment module, a microphone monitoring module, and a control prompt module;

[0007] Judgment color acquisition module: After the teacher logs into the PA system, the camera above the podium is used to obtain the teacher's clothing color as the judgment color. The judgment color is used to determine whether the teacher is in the podium area. The judgment color information is sent to the shielded PA module and the teacher movement judgment module;

[0008] Shielded sound amplification module: When the color is judged to be in the podium area, the microphone on the podium table and the microphone on the top of the podium are automatically turned on. When the teacher speaks, the microphone that receives the voice is automatically shielded, and the voice information of the microphone that receives the voice first is transmitted to the digital audio processor. The voice information is pre-processed by the digital audio processor and then amplified through the speakers installed inside the classroom;

[0009] Teacher movement judgment module: During the sound amplification process, the teacher's movement is judged based on whether the judgment color is located in the podium area, and the teacher's movement judgment result is sent to the control prompt module;

[0010] Microphone monitoring module: During the sound amplification process, the harmonic distortion and signal-to-noise ratio of the microphone on the lectern and the microphone on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and the signal-to-noise ratio, a sound capture score is generated for the microphone on the lectern and the microphone on the top of the podium. The abnormal state of the microphone on the lectern and the microphone on the top of the podium is judged by comparing the sound capture score with the score threshold, and the abnormal state judgment result is sent to the control prompt module;

[0011] Control prompt module: Use fuzzy logic to determine whether to send voice prompts to the teacher's headset and control the microphone operation based on abnormal conditions and teacher movements.

[0012] In a preferred embodiment, when a microphone receives speech first, the shielding and amplification module automatically generates a shielding trigger signal and sends the shielding trigger signal to the microphone that receives the speech later, notifying the microphone that receives the speech later to stop receiving speech. After receiving the shielding signal, the microphone that receives the speech later stops receiving speech and enters a shielding state. When the teacher signals to stop, the shielding and amplification module automatically turns on the shielded microphone.

[0013] In a preferred embodiment, the microphone monitoring module normalizes the harmonic distortion and the signal-to-noise ratio so that the value ranges of the harmonic distortion and the signal-to-noise ratio are mapped to [0, 1], obtains the normalized value of the harmonic distortion and the normalized value of the signal-to-noise ratio, and subtracts the normalized value of the harmonic distortion from the normalized value of the signal-to-noise ratio to obtain the sound capture score;

[0014] If the sound capture score of the microphone on the desk is greater than or equal to the score threshold, it is judged that there is no abnormality in the microphone on the desk; if the sound capture score of the microphone on the desk is less than the score threshold, it is judged that there is an abnormality in the microphone on the desk;

[0015] If the sound capture score of the hanging microphone on the top of the podium is greater than or equal to the scoring threshold, it is judged that there is no abnormality in the hanging microphone on the top of the podium. If the sound capture score of the hanging microphone on the top of the podium is less than the scoring threshold, it is judged that there is an abnormality in the hanging microphone on the top of the podium.

[0016] In a preferred embodiment, the control prompt module defines the abnormal state of the microphone mounted on the top of the podium, the abnormal state of the microphone on the desk, and the teacher's movements as input variables, which are divided into different fuzzy sets respectively, and defines voice prompts and control of microphone operation as output variables, which are divided into different fuzzy sets respectively, formulates a set of fuzzy rules to describe the influence of different input variables on the output variables, performs fuzzy reasoning according to the fuzzy rules, and determines whether to issue voice prompts to the teacher's headset and control the microphone operation.

[0017] In a preferred embodiment, the calculation logic of the harmonic distortion is: monitoring the effective value of the microphone main frequency and the effective values ​​of several harmonic frequencies, and calculating the harmonic distortion through the effective value of the main frequency and several harmonic frequencies, and the expression is:

[0018] Where THD is harmonic distortion, n is the harmonic order, V 1 is the effective value of the main frequency, V i Represents the effective value of the i-th harmonic frequency.

[0019] In a preferred embodiment, the calculation logic of the signal-to-noise ratio is: calculate the signal energy from the sound signal collected by the microphone, calculate the background noise energy from the sound signal collected by the microphone, and calculate the signal-to-noise ratio by the signal energy and the noise energy. The expression is: Where SNR is the signal-to-noise ratio, XHN is the signal energy, and ZSN is the noise energy.

[0020] In a preferred embodiment, the digital audio processor performs noise suppression, feedback suppression, and automatic gain control on the voice information.

[0021] An intelligent sound amplification method for teaching sound amplification, the sound amplification method comprising the following steps:

[0022] After the teacher logs into the PA system, the PA system uses the camera above the podium to obtain the color of the teacher's clothing as the judgment color. When the judgment color is in the podium area, the PA system automatically turns on the microphone on the podium desk and the microphone mounted on the top of the podium.

[0023] When the teacher speaks, the sound reinforcement system automatically shields the microphone that receives the speech, and the microphone that receives the speech first transmits the speech information to the digital audio processor, which pre-processes the speech information and then amplifies it through the speakers installed inside the classroom.

[0024] During the sound amplification process, the teacher's movement is judged based on whether the color is located in the podium area, and the harmonic distortion and signal-to-noise ratio of the microphone on the podium and the microphone mounted on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the podium and the microphone mounted on the top of the podium. The abnormal state of the microphone on the podium and the microphone mounted on the top of the podium is judged by comparing the sound capture score with the score threshold;

[0025] The PA system uses fuzzy logic to determine whether to send voice prompts to the teacher's headset and control the microphone operation according to abnormal conditions and the teacher's movements.

[0026] In the above technical solution, the technical effects and advantages provided by the present invention are:

[0027] The present invention uses a teacher's movement judgment module to judge the teacher's movement according to whether the color is located in the podium area during the sound amplification process. The microphone monitoring module monitors the harmonic distortion and signal-to-noise ratio of the microphone on the desk and the microphone on the top of the podium during the sound amplification process. After pre-processing the harmonic distortion and the signal-to-noise ratio, a sound capture score is generated for the microphone on the desk and the microphone on the top of the podium. The abnormal state of the microphone on the desk and the microphone on the top of the podium is judged by comparing the sound capture score with the score threshold. The control prompt module uses fuzzy logic to judge whether to send a voice prompt to the teacher's earphone and control the microphone operation according to the abnormal state and the teacher's movement. The sound amplification system can give the teacher corresponding voice prompts and control the microphone in combination with the teacher's movement and the operating state of the microphone in use, which not only reduces the overall energy consumption of the sound amplification system, but also effectively guarantees the stable use of the sound amplification system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a system module diagram of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example 1: Please refer to Figure 1 As shown, the intelligent sound amplification system for teaching sound amplification described in this embodiment includes a judgment color acquisition module, a shielding sound amplification module, a teacher movement judgment module, a microphone monitoring module, and a control prompt module;

[0032] Judgment color acquisition module: After the teacher logs into the PA system, the camera above the podium is used to obtain the teacher's clothing color as the judgment color. The judgment color is used to determine whether the teacher is in the podium area. The judgment color information is sent to the shielded PA module and the teacher movement judgment module;

[0033] Shielded sound amplification module: When the color is judged to be in the podium area, the microphone on the podium table and the microphone on the top of the podium are automatically turned on. When the teacher speaks, the microphone that receives the voice is automatically shielded, and the voice information of the microphone that receives the voice first is transmitted to the digital audio processor. The voice information is pre-processed by the digital audio processor and then amplified through the speakers installed inside the classroom;

[0034] Teacher movement judgment module: During the sound amplification process, the teacher's movement is judged based on whether the judgment color is located in the podium area, and the teacher's movement judgment result is sent to the control prompt module;

[0035] Microphone monitoring module: During the sound amplification process, the harmonic distortion and signal-to-noise ratio of the microphone on the lectern and the microphone on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and the signal-to-noise ratio, a sound capture score is generated for the microphone on the lectern and the microphone on the top of the podium. The abnormal state of the microphone on the lectern and the microphone on the top of the podium is judged by comparing the sound capture score with the score threshold, and the abnormal state judgment result is sent to the control prompt module;

[0036] Control prompt module: Use fuzzy logic to determine whether to send voice prompts to the teacher's headset and control the microphone operation based on abnormal conditions and teacher movements.

[0037] This application uses the teacher movement judgment module to judge the teacher's movement during the sound amplification process based on whether the color is located in the podium area. The microphone monitoring module monitors the harmonic distortion and signal-to-noise ratio of the microphone on the podium and the microphone mounted on the top of the podium during the sound amplification process. After pre-processing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the podium and the microphone mounted on the top of the podium. The abnormal state of the microphone on the podium and the microphone mounted on the top of the podium is judged by comparing the sound capture score with the score threshold. The control prompt module uses fuzzy logic to determine whether to send a voice prompt to the teacher's headset and control the microphone operation based on the abnormal state and the teacher's movement. The sound amplification system can provide corresponding voice prompts and control the microphone to the teacher in combination with the teacher's movement and the operating status of the microphone in use, which not only reduces the overall energy consumption of the sound amplification system, but also effectively ensures the stable use of the sound amplification system.

[0038] The specific working process of the sound reinforcement system is as follows:

[0039] After the teacher logs into the PA system, the PA system obtains the color of the teacher's clothing as the judgment color through the camera above the podium. The judgment color is used to determine whether the teacher is in the podium area. When the judgment color is in the podium area, the PA system automatically turns on the microphone on the podium and the microphone suspended on the top of the podium. When the teacher speaks, the PA system automatically shields the microphone that receives the voice later. The microphone that receives the voice first transmits the voice information to the digital audio processor. The digital audio processor pre-processes the voice information and then amplifies it through the speakers installed inside the classroom. During the amplification process, the teacher's movement is determined based on whether the judgment color is in the podium area. The harmonic distortion and signal-to-noise ratio of the microphone on the podium and the microphone suspended on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the podium and the microphone suspended on the top of the podium. The abnormal state of the microphone on the podium and the microphone suspended on the top of the podium is determined by comparing the sound capture score with the score threshold. The PA system uses fuzzy logic to determine whether to send a voice prompt to the teacher's headset and control the operation of the microphone based on the abnormal state and the teacher's movement.

[0040] The installation process of the sound reinforcement system is as follows:

[0041] 1. Place an ASW30 digital audio processor host on the desk in the classroom;

[0042] 2. Install a QG800 high-fidelity and high-sensitivity microphone on the podium, and configure a hanging microphone on the other side of the podium, as well as a three-in-one wireless microphone.

[0043] 3. Hang a JX06A speaker on each wall of the classroom at a distance of 1 / 3 of the total length of the classroom from the blackboard. The power of the classroom should be selected at no less than 0.5W per cubic meter, and the speaker should be selected according to the selected amplifier and the situation of the classroom. For a larger classroom (greater than 120 square meters), a pair of JX06A speakers can be added at the back to achieve uniform sound reinforcement;

[0044] 4. The four-channel microphone input port of the ASW30 digital audio processor can be connected to a hanging microphone, interface microphone, wireless microphone, conference microphone, etc. It can be connected to a central control or computer to achieve long-distance microphone line volume control; it can be connected to an external desktop control box to turn off or on the amplification; after restarting, the system automatically restores the system set volume and amplification on status.

[0045] The sound reinforcement system uses a hanging microphone, a QG800 high-fidelity and high-sensitivity microphone, and a three-in-one wireless microphone to achieve all-round audio collection in the classroom. The hanging microphone can collect sound from up to three meters away, and the QG800 high-fidelity and high-sensitivity microphone can collect sound from up to three meters away. The directivity of the microphone is adjustable, including omnidirectional, cardioid, and single direction (selected through software to prevent students and teachers from affecting the sound collection effect due to misoperation). It is processed by the ASW30 digital audio processor host's internal noise suppression, feedback suppression, automatic gain control, etc., and the sound is clearly amplified from the voice speaker.

[0046] Three-in-one wireless microphone, innovatively integrated 2.4G, UHF, IR three wireless transmission modes for integrated use. Comprehensively solve the problems of wireless teaching microphones being interfered with, easy to cross-frequency, poor sound quality, bulky, troublesome maintenance, and difficult management. Fully digital transmission, DSP signal processing, digital debugging, and intelligent management. 2.4G and infrared two automatic frequency matching methods, seamless conversion, adapt to any harsh environment. Automatically detect the working environment when powered on and automatically select the optimal working solution. Professional microphone sound quality, 48K, 16bit, 30~20KHz wide frequency response, no sense of delay. Support wireless charging, put down to charge, pick up to speak, and speak freely. Built-in large-capacity lithium battery, fully intelligent charging management, with wireless charging function, long battery life, zero maintenance. Integrated intelligent sensor, put down to mute, pick up to speak; automatic standby when not used for timeout. Provide interface support to access the school management platform, and manage all microphones intelligently online. Integrate three functions of microphone, laser pointer, and wireless PPT page turning, and support button function customization. Built-in microphone core, supports external microphone. OLED display, clearly displays system status and parameters, supports display interface customization. Automatic mute function, automatic voice fast recovery, easy to use in noisy environment. Type C charging port, keep up with the trend of technology, avoid mis-insertion, more reliable and durable. Built-in DSP digital anti-howling function.

[0047] Embodiment 2: After the teacher logs into the sound reinforcement system, the judgment color acquisition module acquires the color of the teacher's clothing as the judgment color through the camera above the podium. The judgment color is used to determine whether the teacher is in the podium area;

[0048] When the teacher logs into the PA system at the computer on the desk, the camera above the console of the judgment color acquisition module is running, and the teacher's image is extracted from the background using background segmentation technology to more accurately identify the teacher's clothing color. In the teacher image after background segmentation, the color value of each pixel in the image is calculated and the color value is statistically analyzed to extract the teacher's clothing color. According to the statistical analysis results of the color, the range or threshold of the teacher's clothing color is determined. For example, if the statistical analysis shows that the color of most pixels is within the blue range, blue is determined to be the teacher's clothing color;

[0049] The background segmentation technology can be an existing technology based on a deep learning semantic segmentation model (such as Mask R-CNN), which will not be described in detail here.

[0050] When the color is judged to be in the podium area, the shielding and amplification module automatically turns on the microphone on the podium table and the microphone suspended on the top of the podium. When the teacher speaks, the microphone that receives the voice is automatically shielded, and the voice information of the microphone that receives the voice first is transmitted to the digital audio processor. The voice information is pre-processed by the digital audio processor and then amplified through the speakers installed inside the classroom.

[0051] When the teacher speaks, the shielded amplification module automatically shields the microphone that receives the voice later and transmits the voice information of the microphone that receives the voice first to the digital audio processor, because there are microphones on the desk and microphones hanging on the top of the podium in the podium area, and the teacher may be walking in the podium area, so the teacher may be close to the microphone on the desk or the microphone hanging on the top of the podium. Therefore, in order to avoid the two microphones capturing the voice at the same time and causing the voice amplification to overlap, the shielded amplification module automatically shields the microphone that receives the voice later and transmits the voice information of the microphone that receives the voice first to the digital audio processor.

[0052] When a microphone receives speech first, the shielding amplification module automatically generates a shielding trigger signal and sends the shielding trigger signal to the microphone that receives speech later, notifying it to stop receiving speech. After receiving the shielding signal, the microphone that receives speech later stops receiving speech and enters the shielding state. When the teacher signals to stop, the shielding amplification module automatically turns on the shielded microphone.

[0053] The shielded sound amplification module pre-processes the voice information through a digital audio processor and then amplifies it through the speakers installed inside the classroom;

[0054] The digital audio processor performs noise suppression, feedback suppression, and automatic gain control on voice information. The specific process is as follows:

[0055] Noise suppression: First, the digital audio processor estimates the noise in the environment, usually using technologies such as adaptive filters or spectral subtraction, and then extracts noise features from the input signal, such as energy, spectral distribution, etc., and uses the noise features and environmental noise estimation results to establish a noise model for subsequent suppression processing. Based on the established noise model, the digital audio processor performs real-time noise suppression processing on the input signal, usually using technologies such as adaptive filters, spectral subtraction, and frequency domain filtering to reduce or eliminate noise components to improve speech clarity and intelligibility;

[0056] Feedback suppression: The digital audio processor builds a model of the feedback path to estimate possible feedback signals and monitor the feedback signal components in the input signal in real time. This is usually achieved through methods such as adaptive filters or autocorrelation functions. Once the feedback signal is detected, the digital audio processor will take corresponding suppression measures, usually through dynamic filters or adaptive filters to weaken or eliminate the feedback signal to prevent sound loops and improve stability.

[0057] Automatic Gain Control (AGC): The digital audio processor measures the energy of the input signal in real time to understand the signal strength and dynamic range. Based on the signal energy measurement results and the preset target gain level, the digital audio processor automatically adjusts the signal gain to ensure that the output signal strength is within an appropriate range, which can not only ensure the clarity of the voice, but also avoid signal overload or distortion.

[0058] Teacher movement judgment module: During the sound amplification process, the teacher's movement is judged based on whether the judgment color is located in the podium area;

[0059] The teacher movement judgment module obtains the judgment color and the podium area through the judgment color acquisition module. When the judgment color is in the podium area, it indicates that the teacher is in the podium area. At this time, the microphone on the podium table and the microphone on the top of the podium are still turned on. When the judgment color is not in the podium area, it indicates that the teacher is not in the podium area. At this time, the microphone on the podium table and the microphone on the top of the podium are turned off.

[0060] Microphone monitoring module: During the sound amplification process, the harmonic distortion and signal-to-noise ratio of the microphone on the lectern and the microphone on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the lectern and the microphone on the top of the podium. The abnormal status of the microphone on the lectern and the microphone on the top of the podium is determined by comparing the sound capture score with the score threshold.

[0061] The calculation logic of harmonic distortion is: monitor the effective value of the microphone main frequency and several harmonic frequencies, and calculate the harmonic distortion through the effective value of the main frequency and several harmonic frequencies. The expression is:

[0062] Where THD is harmonic distortion, n is the harmonic order, V 1 is the effective value of the main frequency, V i Represents the effective value of the i-th harmonic frequency.

[0063] When the harmonic distortion is large, the microphone may have the following abnormalities:

[0064] Non-Linear Distortion: High total harmonic distortion usually indicates non-linear distortion in the microphone or its circuitry. In a non-linear system, the output of the signal will contain harmonic components at multiples of the input signal frequency. This can be caused by aging, damage, or poor design of the microphone's internal components.

[0065] Degraded sound quality: Higher harmonic distortion will lead to degraded sound quality, making the output sound unclear, distorted, or noisy. This will affect the sound quality of the microphone and reduce the user experience.

[0066] Signal distortion: Harmonic distortion may cause the sound signal output by the microphone to be significantly different from the input signal. This may affect the actual use of the microphone, especially in situations where high fidelity and accuracy are required, such as recording, speech recognition, etc.

[0067] Unstable operation: Higher harmonic distortion may cause unstable operation of the microphone, and the sound may shake, fluctuate or be discontinuous, which will affect the normal use of the microphone.

[0068] Shortened equipment life: Long-term presence of high harmonic distortion may accelerate the aging and damage of microphone internal components, resulting in shortened equipment life and increased repair and replacement costs.

[0069] The calculation logic of the signal-to-noise ratio is: calculate the signal energy from the sound signal collected by the microphone, calculate the background noise energy from the sound signal collected by the microphone, and calculate the signal-to-noise ratio through the signal energy and the noise energy. The expression is: In the formula, SNR is the signal-to-noise ratio, XHN is the signal energy, and ZSN is the noise energy;

[0070] The calculation expression of signal energy is: Where A represents the number of sound signal sampling points, w a Represents the amplitude value of the ath sampling point in the sound signal;

[0071] The calculation expression of noise energy is: In the formula, B represents the number of background noise signal sampling points, g b Represents the amplitude value of the bth sampling point in the background noise signal.

[0072] If the signal-to-noise ratio is low, it indicates that the microphone has the following abnormalities:

[0073] Increased noise interference: A low signal-to-noise ratio means that the background noise is more significant than the signal, which may be due to an increase in the noise level of the microphone itself or increased noise interference in the environment. This may be caused by aging, damage or improper design of the internal components of the microphone.

[0074] Deterioration of sound quality: The increase in noise will cause aliasing between the sound signal and the noise, reducing the clarity and accuracy of the sound, thereby reducing the sound quality of the microphone.

[0075] Difficulty in speech recognition: In situations where the signal-to-noise ratio is low, speech recognition systems may face greater challenges because noise interference may make it difficult for speech recognition algorithms to accurately distinguish speech signals from noise.

[0076] Reduced user experience: For application scenarios that require clear and accurate transmission of sound information, such as teleconferencing and voice recording, a low signal-to-noise ratio will reduce the user experience and make communication effects worse.

[0077] Degraded system performance: A lower signal-to-noise ratio may affect the overall performance of the microphone, such as affecting the transmission quality of the communication system or affecting the sound reproduction effect of the audio system.

[0078] After preprocessing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the lectern and the microphone mounted on the top of the podium. The abnormal state of the microphone on the lectern and the microphone mounted on the top of the podium is determined by comparing the sound capture score with the score threshold.

[0079] Normalize the harmonic distortion and signal-to-noise ratio so that the value ranges of the harmonic distortion and the signal-to-noise ratio are mapped to [0, 1], and obtain the normalized value of the harmonic distortion and the normalized value of the signal-to-noise ratio;

[0080] The normalized calculation formula is: In the formula, x norn is the normalized value of the parameter, x is the original parameter, max(x) is the maximum value of the parameter, min(x) is the minimum value of the parameter. The calculation method of the normalized value of the harmonic distortion and the normalized value of the signal-to-noise ratio is the same as the normalized calculation formula, which will not be repeated here.

[0081] In this application, it is necessary to maximize the signal-to-noise ratio and minimize the harmonic distortion, therefore, the normalized value of the harmonic distortion is subtracted from the normalized value of the signal-to-noise ratio to obtain the sound capture score;

[0082] If the sound capture score of the microphone on the desk is greater than or equal to the score threshold, it is judged that there is no abnormality in the microphone on the desk; if the sound capture score of the microphone on the desk is less than the score threshold, it is judged that there is an abnormality in the microphone on the desk;

[0083] If the sound capture score of the hanging microphone on the top of the podium is greater than or equal to the scoring threshold, it is judged that there is no abnormality in the hanging microphone on the top of the podium. If the sound capture score of the hanging microphone on the top of the podium is less than the scoring threshold, it is judged that there is an abnormality in the hanging microphone on the top of the podium.

[0084] The control prompt module uses fuzzy logic to determine whether to send voice prompts to the teacher's headset and control the microphone operation according to abnormal status and teacher's movements;

[0085] The control prompt module defines the abnormal state of the microphone hanging on the podium, the abnormal state of the microphone on the podium, and the teacher's movement as input variables, and divides them into different fuzzy sets respectively;

[0086] The voice prompt and the control microphone operation are defined as output variables and divided into different fuzzy sets respectively;

[0087] A set of fuzzy rules is formulated to describe the influence of different input variables on the output variables. Fuzzy reasoning is performed based on the fuzzy rules to determine whether to send voice prompts to the teacher's headset and control the operation of the microphone.

[0088] Formulate a set of fuzzy rules to describe the impact of different input variables on output variables. The definition of rules can be based on professional knowledge or obtained through data analysis and experiments. For example:

[0089] In this application, the abnormal state of the microphone hanging on the top of the podium is marked as DT, the abnormal state of the microphone on the podium is marked as JT, the teacher's movement is marked as MT, the voice prompt is represented as NC, and the control microphone operation is marked as MC;

[0090] The abnormal state fuzzy set of the microphone hanging on the podium is divided into "abnormal" and "No abnormalities";

[0091] The abnormal state fuzzy set of the microphone on the podium is divided into "abnormal" and "No abnormalities";

[0092] The fuzzy set of teacher movements is divided into “At the podium” and “Not on the podium”;

[0093] The fuzzy set of voice prompts is divided into: "prompt" and "Do not prompt";

[0094] The fuzzy set of controlling microphone operation is divided into "control" and "Uncontrol"

[0095] Then the fuzzy rule can be defined as:

[0096] Rule 1: IF (DT is abnormal) AND (JT is abnormal) AND (MT is at the podium) THEN (NC is prompt) AND (MC is control), where the voice prompt is: "Please turn on the backup handheld microphone (i.e., the three-in-one wireless microphone mentioned in this application)", and the microphone control operation is: turn off the microphone on the top of the podium and the microphone on the desk. This rule indicates that both the microphone on the top and the microphone on the desk are abnormal and cannot be used, so the backup handheld microphone needs to be turned on;

[0097] Rule 2: IF (DT is No abnormalities) AND (JT is No abnormalities) AND (MT is Not on the podium) THEN (NC is prompt) AND (MC is control), where the voice prompt is: "Please turn on the backup handheld microphone (i.e., the three-in-one wireless microphone mentioned in this application)", and the microphone operation is controlled as follows: turn off the microphone mounted on the top of the podium and the microphone on the desk. This rule indicates that the teacher is not on the podium, so the backup microphone needs to be turned on;

[0098] Rule 3:IF(DT is abnormal)AND(JT is No abnormalities)AND(MT is At the podium)THEN(NC is Do not prompt)AND(MC is control), the microphone operation is controlled as follows: turn off the microphone with abnormality...; This rule indicates that a certain microphone at the podium is not supported for use, but another microphone is supported for use, and you only need to turn off the microphone that is not supported for use.

[0099] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0100] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0101] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0102] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the above-described system, device and unit can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0103] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An intelligent sound amplification system for teaching, characterized by: It includes a color determination module, a sound amplification module, a teacher's movement determination module, a microphone monitoring module, and a control prompt module; Judgment color acquisition module: After the teacher logs into the PA system, the camera above the podium is used to obtain the teacher's clothing color as the judgment color. The judgment color is used to determine whether the teacher is in the podium area. The judgment color information is sent to the shielded PA module and the teacher movement judgment module; Shielded sound amplification module: When the color is judged to be in the podium area, the microphone on the podium table and the microphone on the top of the podium are automatically turned on. When the teacher speaks, the microphone that receives the voice is automatically shielded, and the voice information of the microphone that receives the voice first is transmitted to the digital audio processor. The voice information is pre-processed by the digital audio processor and then amplified through the speakers installed inside the classroom; Teacher movement judgment module: During the sound amplification process, the teacher's movement is judged based on whether the judgment color is located in the podium area, and the teacher's movement judgment result is sent to the control prompt module; Microphone monitoring module: During the sound amplification process, the harmonic distortion and signal-to-noise ratio of the microphone on the lectern and the microphone on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the lectern and the microphone on the top of the podium. The abnormal status of the microphone on the lectern and the microphone on the top of the podium is determined by comparing the sound capture score with the score threshold. The microphone monitoring module normalizes the harmonic distortion and signal-to-noise ratio so that the value ranges of the harmonic distortion and the signal-to-noise ratio are mapped to [0,1], obtains the normalized value of the harmonic distortion and the normalized value of the signal-to-noise ratio, and subtracts the normalized value of the harmonic distortion from the normalized value of the signal-to-noise ratio to obtain the sound capture score; If the sound capture score of the microphone on the desk is greater than or equal to the score threshold, it is judged that there is no abnormality in the microphone on the desk; if the sound capture score of the microphone on the desk is less than the score threshold, it is judged that there is an abnormality in the microphone on the desk; If the sound capture score of the microphone hanging on the top of the podium is greater than or equal to the score threshold, it is judged that there is no abnormality in the microphone hanging on the top of the podium; if the sound capture score of the microphone hanging on the top of the podium is less than the score threshold, it is judged that there is an abnormality in the microphone hanging on the top of the podium, and the abnormal state judgment result is sent to the control prompt module; Control prompt module: Based on abnormal status and teacher's movements, fuzzy logic is used to determine whether to send voice prompts to the teacher's headset and control the operation of the microphone; The control prompt module defines the abnormal state of the microphone mounted on the top of the podium, the abnormal state of the microphone on the desk, and the teacher's movements as input variables, which are divided into different fuzzy sets respectively. It defines voice prompts and control of microphone operation as output variables, which are divided into different fuzzy sets respectively. A set of fuzzy rules is formulated to describe the influence of different input variables on the output variables. Fuzzy reasoning is performed according to the fuzzy rules to determine whether to send voice prompts to the teacher's headset and control the microphone operation.

2. The intelligent sound amplification system for teaching according to claim 1, characterized in that: When a microphone receives speech first, the shielding and amplification module automatically generates a shielding trigger signal and sends the shielding trigger signal to the microphone that receives the speech later, notifying the microphone that receives the speech later to stop receiving speech. After receiving the shielding signal, the microphone that receives the speech later stops receiving speech and enters the shielding state. When the teacher signals to stop speaking, the shielding and amplification module automatically turns on the shielded microphone.

3. The intelligent sound amplification system for teaching according to claim 2, characterized in that: The calculation logic of the harmonic distortion is: monitor the effective value of the microphone main frequency and the effective values ​​of several harmonic frequencies, and calculate the harmonic distortion through the effective value of the main frequency and several harmonic frequencies. The expression is: , where is the harmonic distortion, is the harmonic order, is the effective value of the main frequency, Indicates The effective value of harmonic frequency.

4. The intelligent sound amplification system for teaching according to claim 3, characterized in that: The calculation logic of the signal-to-noise ratio is: calculate the signal energy from the sound signal collected by the microphone, calculate the background noise energy from the sound signal collected by the microphone, and calculate the signal-to-noise ratio through the signal energy and the noise energy. The expression is: , where is the signal-to-noise ratio, is the signal energy, is the noise energy.

5. The intelligent sound amplification system for teaching according to claim 4, characterized in that: The digital audio processor performs noise suppression, feedback suppression, and automatic gain control on voice information.

6. An intelligent sound amplification method for teaching sound amplification, implemented by the sound amplification system according to any one of claims 1 to 5, characterized in that: The sound amplification method comprises the following steps: After the teacher logs into the PA system, the PA system uses the camera above the podium to obtain the color of the teacher's clothing as the judgment color. When the judgment color is in the podium area, the PA system automatically turns on the microphone on the podium desk and the microphone mounted on the top of the podium. When the teacher speaks, the sound reinforcement system automatically shields the microphone that receives the speech, and the microphone that receives the speech first transmits the speech information to the digital audio processor, which pre-processes the speech information and then amplifies it through the speakers installed inside the classroom. During the sound amplification process, the teacher's movement is judged based on whether the color is located in the podium area, and the harmonic distortion and signal-to-noise ratio of the microphone on the podium and the microphone mounted on the top of the podium are monitored for a period of time. After pre-processing the harmonic distortion and signal-to-noise ratio, a sound capture score is generated for the microphone on the podium and the microphone mounted on the top of the podium. The abnormal state of the microphone on the podium and the microphone mounted on the top of the podium is judged by comparing the sound capture score with the score threshold; The PA system uses fuzzy logic to determine whether to send voice prompts to the teacher's headset and control the microphone operation according to abnormal conditions and the teacher's movements.

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