Audio processing circuit, audio processing method, audio processing equipment and audio mixer

Abstract

The invention provides an audio processing circuit, an audio processing method, audio processing equipment and an audio mixer. The audio processing circuit comprises a first input module and a second input module which are used for inputting audio signals; the sound mixing module is used for carrying out sound mixing processing on the first audio signal and the second audio signal; the gain regulator is connected with the second input module and is used for regulating the gain of the second sound mixing link; the voltage detection module is connected with the first input module and is used for detecting the peak voltage of the first audio signal and comparing the peak voltage with a preset voltage threshold value; the control module is respectively connected with the voltage detection module and the gain regulator, and is used for controlling the first sound mixing link to be switched on and controlling the gain of the second sound mixing link to be reduced when the peak voltage is greater than a preset voltage threshold value, and also used for controlling the first sound mixing link to be switched off when the peak voltage is less than the preset voltage threshold value, and controlling the gain of the second sound mixing link to be reduced; and the gain of the second sound mixing link is controlled to be increased. According to the invention, invalid sound source noise does not participate in sound mixing, and the signal-to-noise ratio of sound mixing output is improved.

Description

Technical Field

[0001] The present application relates to the technical field of audio processing, and in particular to an audio processing circuit, method, device and mixer. Background Art

[0002] Mixing is an audio processing technique. Mixing is the process of combining multiple sounds into one or more channels. In this process, the volume level, frequency content, dynamics and panoramic position of the source are manipulated or enhanced.

[0003] Currently, there are two commonly used mixing methods in the industry: the first is to mix the microphone sound source audio with other sound source audio. The second is to directly mix the Line in input with the audio processor, using direct addition processing. The problem with the first mixing method is that the microphone picks up long-distance environmental noise and circuit noise and continuously participates in the mixing, causing the signal-to-noise ratio of the output sound after mixing of other sound sources to be seriously reduced when there is no effective sound source. In the second mixing method, the root cause of the problem of mixing the Line in input with the audio processor is that the radiation coupling noise of the Line in connection cable and the output noise of the external low signal-to-noise ratio sound source continuously participate in the mixing, causing the signal-to-noise ratio of the output sound after mixing of other sound sources to be seriously reduced when there is no effective sound source input to the Line in.

[0004] In the above mixing method, the reason why the output sound signal-to-noise ratio is seriously reduced is that the mixed output sound changes from high signal-to-noise ratio and high sound quality input to ordinary signal-to-noise ratio and ordinary sound quality output, or even from high signal-to-noise ratio and high sound quality input to low signal-to-noise ratio and low sound quality output. The ordinary sound quality or low sound quality output amplification brings a very bad audio experience to users. Summary of the invention

[0005] The main purpose of the embodiments of the present application is to provide an audio processing circuit, method, device and mixer to prevent invalid sound source noise from participating in mixing, reduce circuit mixing output noise, and improve the signal-to-noise ratio of the mixing output.

[0006] In a first aspect, an embodiment of the present application provides an audio processing circuit, comprising: a first input module, for inputting a first audio signal to be processed; a second input module, for inputting a second audio signal to be processed; a mixing module, connected to the first input module to form a first mixing link, the mixing module connected to the second input module to form a second mixing link, for mixing the first audio signal and the second audio signal; a gain adjuster, connected to the second input module, for adjusting the gain of the second mixing link; a voltage detection module, connected to the first input module, for detecting a peak voltage of the first audio signal, and comparing the peak voltage with a preset voltage threshold, and outputting a voltage comparison result; a control module, connected to the voltage detection module and the gain adjuster, respectively, for controlling the first mixing link to be turned on when the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, and controlling the gain adjuster to reduce the gain of the second mixing link to a first threshold; the control module is also used to control the first mixing link to be disconnected when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, and control the gain adjuster to increase the gain of the second mixing link to a second threshold, the second threshold being greater than the first threshold.

[0007] In one embodiment, the control module includes: a switch connected to the first mixing link, when the switch is closed, the first mixing link is turned on, and when the switch is opened, the first mixing link is disconnected; the switch is used to control the switch to be closed when the voltage comparison result is that the peak voltage is greater than the preset voltage threshold.

[0008] In one embodiment, the switch is further configured to control the switch to be disconnected when the voltage comparison result is that the peak voltage is less than the preset voltage threshold.

[0009] In one embodiment, the voltage detection module includes: a voltage detector connected to the first input module and used to detect the peak voltage of the first audio signal; a voltage comparator connected to the voltage detector and the control module, used to compare the peak voltage with a preset voltage threshold and output the voltage comparison result to the control module.

[0010] In one embodiment, the gain adjuster includes: an adjustable potentiometer; the control module also includes: a controller;

[0011] The controller is connected to the voltage comparator and is used to control the resistance of the adjustable potentiometer to increase to a first resistance value when the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold, so as to reduce the gain of the second mixing link to the first threshold.

[0012] In one embodiment, the controller is further used to control the resistance of the adjustable potentiometer to decrease to a second resistance value when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, so as to increase the gain of the second mixing link to the second threshold, and the second resistance value is less than the first resistance value.

[0013] In one embodiment, it also includes: a filter connected to the mixing module, used to filter the mixed audio output by the mixing module; and / or an output module connected to the filter, used to output the mixed audio after filtering.

[0014] In a second aspect, an embodiment of the present application provides an audio processing method, which is applied to the circuit described in any one of the above aspects, and the method includes: obtaining the peak voltage of the first audio signal, and comparing the peak voltage with a preset voltage threshold to determine a voltage comparison result; when the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, controlling the first mixing link to be turned on, and controlling the gain adjuster to reduce the gain of the second mixing link to a first threshold; when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, controlling the first mixing link to be disconnected, and controlling the gain adjuster to increase the gain of the second mixing link to a second threshold, and the second threshold is greater than the first threshold.

[0015] In a third aspect, an embodiment of the present application provides an electronic device, including:

[0016] at least one processor; and

[0017] a memory communicatively coupled to the at least one processor;

[0018] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the electronic device to execute the method described in any one of the above aspects.

[0019] In a fourth aspect, an embodiment of the present application provides a mixer, comprising the audio processing circuit described in any of the above aspects.

[0020] The audio processing circuit, method, device and mixer provided in the embodiments of the present application detect the peak voltage of the first audio signal input by the first input module through the voltage detection module, and compare the peak voltage with the preset voltage threshold. When the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, the first audio signal is determined to be a valid sound source. At this time, the first mixing link where the first input module is located is controlled to be turned on through the control module so that the first audio signal participates in the mixing. At the same time, the gain of the second mixing link is reduced to the first threshold through the gain regulator to achieve audio ducking. On the other hand, when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, the first audio signal is determined to be an invalid sound source. At this time, the first mixing link can be controlled to be disconnected through the control module so that the invalid first audio signal does not participate in the mixing. At the same time, the gain of the second mixing link is increased to the second threshold through the gain regulator. In this way, the invalid sound source noise does not participate in the mixing, the circuit mixing output noise is reduced, and the signal-to-noise ratio of the mixing output is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application. Obviously, the drawings described below are some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0022] Figure 1 A block diagram of an audio processing circuit provided in an embodiment of the present application;

[0023] Figure 2 A schematic diagram of the architecture of an audio processing circuit provided in an embodiment of the present application;

[0024] Figure 3 A schematic diagram of a simulation circuit of an audio processing circuit provided in an embodiment of the present application;

[0025] Figure 4 A schematic diagram of simulation results of an audio processing circuit provided in an embodiment of the present application;

[0026] Figure 5 A flowchart of an audio processing method provided in an embodiment of the present application;

[0027] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0028] Figure 7 A schematic diagram of the structure of a mixer provided in an embodiment of the present application.

[0029] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0030] Here, exemplary embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application.

[0031] The term "and / or" in this article is used to describe the association relationship of associated objects, specifically indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone.

[0032] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with the relevant laws, regulations and standards of the relevant countries and regions, and provide corresponding operation entrances for users to choose to authorize or refuse.

[0033] In order to clearly describe the technical solution of the embodiment of the present application, the terms involved in the present application are first defined:

[0034] RISC: Reduced Instruction Set Computer RISC, reduced instruction set computer.

[0035] ARM: Advanced RISC Machines, a RISC microprocessor.

[0036] CPU: Central Processing Unit.

[0037] MCU: Microcontroller Unit, micro control unit.

[0038] FPGA: Field Programmable Gate Array, field programmable logic gate array.

[0039] DSP: Digital Signal Processing, digital signal processing technology.

[0040] Mixing is an audio processing technique. Mixing is the process of combining multiple sounds into one or more channels. In this process, the volume level, frequency content, dynamics and panoramic position of the source are manipulated or enhanced.

[0041] Currently, there are two commonly used mixing methods in the industry: the first is to mix the microphone sound source audio with other sound source audio. The second is to directly mix the Line in input with the audio processor, using direct addition processing. The problem with the first mixing method is that the microphone picks up long-distance environmental noise and circuit noise and continuously participates in the mixing, causing the signal-to-noise ratio of the output sound after mixing of other sound sources to be seriously reduced when there is no effective sound source. In the second mixing method, the root cause of the problem of mixing the Line in input with the audio processor is that the radiation coupling noise of the Line in connection cable and the output noise of the external low signal-to-noise ratio sound source continuously participate in the mixing, causing the signal-to-noise ratio of the output sound after mixing of other sound sources to be seriously reduced when there is no effective sound source input to the Line in.

[0042] In the above mixing method, the reason why the output sound signal-to-noise ratio is seriously reduced is that the mixed output sound changes from high signal-to-noise ratio and high sound quality input to ordinary signal-to-noise ratio and ordinary sound quality output, or even from high signal-to-noise ratio and high sound quality input to low signal-to-noise ratio and low sound quality output. The ordinary sound quality or low sound quality output amplification brings a very bad audio experience to users.

[0043] In order to solve the above problems, an embodiment of the present application provides an audio processing solution, in which the peak voltage of the first audio signal input by the first input module is detected by a voltage detection module, and the peak voltage is compared with a preset voltage threshold. When the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, the first audio signal is determined to be a valid sound source. At this time, the first mixing link where the first input module is located is controlled to be turned on by the control module so that the first audio signal participates in the mixing. At the same time, the gain of the second mixing link is adjusted to the first threshold through the gain regulator to achieve audio ducking. On the other hand, when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, the first audio signal is determined to be an invalid sound source. At this time, the first mixing link can be controlled to be disconnected by the control module so that the invalid first audio signal does not participate in the mixing. At the same time, the gain of the second mixing link is adjusted to the second threshold through the gain regulator. In this way, the invalid sound source noise does not participate in the mixing, the circuit mixing output noise is reduced, and the signal-to-noise ratio of the mixing output is improved.

[0044] Some embodiments of the present application are described in detail below in conjunction with the accompanying drawings. In the case where there is no conflict between the embodiments, the following embodiments and the features in the embodiments can be combined with each other. In addition, the step sequence in the following method embodiments is only an example and not a strict limitation.

[0045] Please see Figure 1 , which is a schematic diagram of an audio processing circuit 100 according to an embodiment of the present application, mainly comprising: a first input module 101, a second input module 102, a mixing module 103, a gain regulator 104, a voltage detection module 105 and a control module 106, and the functions of each module are as follows:

[0046] The first input module 101 is used to input the first audio signal to be processed. Here, the first audio signal can be a sound signal in the current environment, such as a sound signal collected in real time by a microphone in a teaching, stage, or singing room. The first audio signal can also be a pre-recorded sound signal, such as a sound source signal input by Line in.

[0047] The second input module 102 is used to input a second audio signal to be processed. Here, the second audio signal can be a pre-recorded high-quality sound source signal, such as a courseware sound source signal in a teaching scene, a promotional video sound source signal in a stage scene, a background music accompaniment function sound source signal in a singing room scene, etc. The second audio signal can simulate an audio signal.

[0048] The mixing module 103 is connected to the first input module 101 to form a first mixing link, and is connected to the second input module 102 to form a second mixing link, for mixing the first audio signal and the second audio signal. The mixing module 103 can be implemented using an inverse adder.

[0049] The gain adjuster 104 is connected to the second input module 102 and is used to adjust the gain of the second mixing link.

[0050] The voltage detection module 105 is connected to the first input module 101 and is used to detect the peak voltage of the first audio signal, compare the peak voltage with a preset voltage threshold, and output a voltage comparison result.

[0051] The control module 106 is connected to the voltage detection module 105 and the gain regulator 104, respectively, and is used to control the first mixing link to be turned on when the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold, and control the gain regulator 104 to reduce the gain of the second mixing link to a first threshold. Here, the first threshold may be a preset negative gain value.

[0052] The control module 106 is further configured to control the first mixing link to be disconnected when the voltage comparison result shows that the peak voltage is less than the preset voltage threshold, and control the gain regulator 104 to increase the gain of the second mixing link to a second threshold, which is greater than the first threshold. Here, the second threshold may be 0 dB.

[0053] In this embodiment, the peak voltage of the first audio signal input by the first input module 101 is detected by the voltage detection module 105, and the peak voltage is compared with the preset voltage threshold. When the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, the first audio signal is determined to be a valid sound source. At this time, the first mixing link where the first input module 101 is located is controlled to be turned on by the control module 106, so that the first audio signal participates in the mixing. At the same time, the gain of the second mixing link is adjusted to the first threshold by the gain regulator 104 to achieve audio ducking. On the other hand, when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, the first audio signal is determined to be an invalid sound source. At this time, the first mixing link can be controlled to be disconnected by the control module 106, so that the invalid first audio signal does not participate in the mixing. At the same time, the gain of the second mixing link is adjusted to the second threshold by the gain regulator 104. In this way, the invalid sound source noise does not participate in the mixing, the circuit mixing output noise is reduced, and the signal-to-noise ratio of the mixing output is improved.

[0054] Please see Figure 2 , which is an audio processing circuit 100 of an embodiment of the present application, wherein the first audio signal and the second audio signal can both be analog audio signals, the first audio signal takes the analog audio input signal 1 (i.e., Uin(1)) as an example, and the second audio signal takes the multiple analog audio input signals 2~n (i.e., Uin(2)~Uin(n)) as an example, where n is a positive integer.

[0055] The mixing module 103 can be implemented by an analog mixing module 7 including an inverse adder, which is used to adjust the voltages of Uin(2) to Uin(n) after gain and superimpose them with the processed voltage of Uin(1), and invert the phase of the superimposed analog audio signal.

[0056] In one embodiment, the voltage detection module 105 may specifically include: a voltage detector 2 and a voltage comparator 3, wherein:

[0057] The voltage detector 2 is connected to the first input module 101 and is used to detect the peak voltage of the first audio signal. The voltage detector 2 may be a voltage detector 2 with a slow discharge dynamic peak voltage detection function, which is used to dynamically obtain the AC peak voltage of the analog audio input signal Uin(1).

[0058] The voltage comparator 3 is connected to the voltage detector 2 and the control module 106, and is used to compare the peak voltage with the preset voltage threshold, and output the voltage comparison result to the control module 106. Specifically, the voltage comparator 3 compares the magnitude relationship between the peak voltage output by the voltage detector 2 and the preset voltage threshold, and outputs the voltage comparison result.

[0059] In one embodiment, the control module 106 may specifically include: a controller 5 and a switch, wherein:

[0060] The switch is connected to the first mixing link. In an optional embodiment, the switch is respectively connected to the first input module 101, the voltage detection module 105 and the mixing module 103. When the switch is closed, the first mixing link is turned on. When the switch is opened, the first mixing link is disconnected. The switch here can be implemented by an automatic mixing switching analog switch 4. The analog switch 4 is connected to the voltage comparator 3. The voltage comparator 3 can automatically generate a control signal Control(1) to the analog switch 4 according to the voltage comparison result, and automatically close or open the analog switch 4 under the action of the control signal Control(1).

[0061] Specifically, when the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, Uin(1) is determined to be a valid sound source, and the voltage comparator 3 generates a switch closure control signal and sends it to the analog switch 4 to control the analog switch 4 to close, thereby turning on the first mixing link, and Uin(1) participates in the mixing process.

[0062] The controller 5 is connected to the voltage comparator 3 and is used to generate a corresponding control signal according to the voltage comparison result output by the voltage comparator 3. The controller 5 can be implemented by one or more of ARM, CPU, MCU, FPGA and DSP.

[0063] In one embodiment, the switch is further configured to control the switch to be disconnected when the voltage comparison result shows that the peak voltage is less than a preset voltage threshold.

[0064] In this embodiment, when the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold, Uin(1) is determined to be an invalid sound source, such as noise. At this time, the voltage comparator 3 can generate a switch disconnection control signal and send it to the analog switch 4 to control the analog switch 4 to disconnect. When the switch is disconnected, the first mixing link is disconnected, so that Uin(1) does not participate in the mixing, thus preventing noise from participating in the mixing and improving the signal-to-noise ratio of the mixing output.

[0065] In one embodiment, the gain regulator 104 includes an adjustable potentiometer 6. The controller 5 is further configured to control the resistance of the adjustable potentiometer 6 to be increased to a first resistance value when the voltage comparison result shows that the peak voltage is greater than a preset voltage threshold, so as to reduce the gain of the second mixing link to the first threshold.

[0066] In this embodiment, the gain adjuster 104 can be implemented by a digital adjustable potentiometer 6, which is connected to the second mixing link where Uin(2)~Uin(n) are located, and is connected to the controller 5, and is used to adjust the gain of the second mixing link according to the control signal Control(2) of the controller 5.

[0067] When the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, Uin(1) is determined to be an effective sound source. At this time, the analog switch 4 is closed, and the first mixing link where the effective input sound source Uin(1) is located is turned on. Uin(1) participates in the mixing. At this time, the controller 5 generates a control signal for increasing the resistance and sends it to the digital adjustable potentiometer 6, so that the resistance of the adjustable potentiometer 6 is continuously and quickly adjusted from a small resistance to a large resistance, thereby making the gain of the second mixing link where Uin(2)~Uin(n) is located quickly decay from 0dB to the set threshold negative gain, for example, the gain is reduced to -A, so as to achieve audio ducking, so that the sound of Uin(1) in the mixing output is clearer.

[0068] For example, in a teaching scenario, the microphone collects the teacher's lecture sound as Uin(1), and the courseware sound source is Uin(2)~Uin(n). When the teacher's lecture sound Uin(1) is the effective sound source, the volume of the courseware sound source Uin(2)~Uin(n) is lowered, so that the teacher's lecture sound is clearer in the mixed output sound, which is easier for students to listen to.

[0069] In one embodiment, the controller 5 is further used to control the resistance of the adjustable potentiometer 6 to decrease to a second resistance value when the voltage comparison result shows that the peak voltage is less than the preset voltage threshold, so as to increase the gain of the second mixing link to a second threshold, and the second resistance value is less than the first resistance value.

[0070] In this embodiment, if the voltage comparison result is that the peak voltage is less than the preset voltage threshold, it means that Uin(1) is an invalid sound source, which may be noise. At this time, the analog switch 4 is disconnected, and the first mixing link where the invalid input sound source Uin(1) is located is disconnected, so that Uin(1) does not participate in the mixing. At this time, the controller 5 generates a control signal for adjusting the resistance to be sent to the adjustable potentiometer 6, so that the resistance value of the adjustable potentiometer 6 is continuously and quickly adjusted from a large resistance to a small resistance, thereby making the gain of the second mixing link where Uin(2)~Uin(n) is located quickly increase from the set threshold negative gain (-A) to 0dB, and Uin(2)~Uin(n) participate in the mixing output normally. In this way, the invalid sound source noise does not participate in the mixing, reducing the circuit mixing output noise and improving the signal-to-noise ratio of the mixing output.

[0071] In one embodiment, the circuit may further include: a filter 8 connected to the mixing module 103 and configured to perform filtering processing on the mixed audio output by the mixing module 103 .

[0072] In this embodiment, the filter 8 may be an analog inverse low-pass filter 8, which is used to filter the mixed audio signal output by the mixing module 103 and inverse the phase of the audio signal.

[0073] In one embodiment, the circuit may further include: an output module, connected to the filter 8, for outputting the mixed audio after filtering.

[0074] In this embodiment, the output module may be implemented with an analog audio output (Uout) 9 for outputting a high-quality mixed audio signal.

[0075] Please see Figure 3 , which is a schematic diagram of a simulation circuit of an audio processing circuit 100 according to an embodiment of the present application, wherein:

[0076] The first audio signal Uin(1) can be generated by a simulator and connected to a voltage detector 2 through a capacitor C4. The voltage detector 2 includes an operational amplifier U7, a diode D1, a diode D2, a diode D3, a resistor R1, a resistor R2, a resistor R6 and a capacitor C1, and AVCC is a power supply voltage. U7 is used for voltage follower isolation so as not to affect the voltage circuit being detected. The combination of D3 and C1 is used to extract the peak voltage of the AC signal, D1 is used to compensate for the voltage drop of D3, D2 and D1 are used to ensure that U7 always works as a follower, and R1 is used to fine-tune the diode voltage drop of D1 to improve the peak voltage detection accuracy. Resistor R2 is used for current limiting to prevent the operational amplifier from directly driving capacitor C1 to work abnormally. Resistor R6 is used to discharge C1 so that the voltage detector 2 can dynamically obtain the peak voltage of the AC audio signal. The voltage detector 2 is connected to the voltage comparator 3 through a resistor R24.

[0077] The voltage comparator 3 includes an operational amplifier U2, a capacitor C2, a resistor R22 and a resistor R23, wherein the resistors R22 and R23 are used to configure a preset voltage threshold, and the capacitor C2 is used to suppress noise. U2 is used to compare the peak voltage of Uin(1) with the preset voltage threshold.

[0078] The output end of the operational amplifier U2 is connected to the field effect transistor T1 of the controller 5. The controller 5 includes the field effect transistor T1 and the resistor R7. The field effect transistor T1 can output multiple control signals for controlling the input audio signals of the multiple second input modules 102. For example, the control signal Ctr(2) is used to control Uin(2), and the control signal Ctr(n) is used to control Uin(n).

[0079] The first audio signal Uin(1) is connected to the analog switch 4 through the capacitor C4. The analog switch 4 may include a switch component U4 and a resistor R10. The resistor R10 is used to provide a common-mode bias voltage so that the input signal is within the operating range of the operational amplifier U7 and the switch component U4. The VDD terminal of the switch component U4 is connected to the power supply voltage, the 1A port is connected to the signal simulator that generates Uin(1), the 1C port is connected to the output terminal of the voltage comparator 3, the 1B port is connected to the mixing module 103, and the GND terminal is grounded.

[0080] The second audio signal Uin(2)~Uin(n) can also be generated by a signal simulator, and connected to a corresponding adjustable potentiometer 6 after passing through a corresponding capacitor. The adjustable potentiometer 6 can be implemented by a digital adjustable potentiometer, and the adjustable potentiometer 6 can be configured with a corresponding switch component, and connected to the controller 5 through the switch component. It is used to adjust the potentiometer resistance value in the gain circuit of the analog input signal Uin(2)~Uin(n), and adjust the gain of the analog input signal Uin(2)~Uin(n).

[0081] For example, Uin(2) is connected to the digital adjustable potentiometer P1 through the capacitor C3 and the resistor R17. The digital adjustable potentiometer P1 is equipped with a switch component U3. The input end of the digital adjustable potentiometer P1 is connected to Uin(2). The output end of the digital adjustable potentiometer P1 is connected to the mixing module 103. The sliding end of the digital adjustable potentiometer P1 is connected to the 1A port of the switch component U3. The VDD end of the switch component U3 is connected to the power supply voltage. The 1C port of the switch component U3 is connected to the Ctr(2) port of the field effect transistor T1 of the controller 5. The 1B port of the switch component U3 is connected to the output end of the digital adjustable potentiometer P1. The GND end is grounded.

[0082] Uin(n) is connected to the digital adjustable potentiometer P2 through the capacitor C7 and the resistor R3. The digital adjustable potentiometer P2 is equipped with a switch component U8. The input end of the digital adjustable potentiometer P2 is connected to Uin(n). The output end of the digital adjustable potentiometer P2 is connected to the mixing module 103. The sliding end of the digital adjustable potentiometer P2 is connected to the 1A port of the switch component U8. The VDD end of the switch component U8 is connected to the power supply voltage. The 1C port of the switch component U8 is connected to the Ctr(n) port of the field effect tube T1 of the controller 5. The 1B port of the switch component U8 is connected to the output end of the digital adjustable potentiometer P2. The GND end is grounded.

[0083] The mixing module 103 includes an operational amplifier U6, a resistor R19, a capacitor C5, a capacitor C6 and a resistor R20. The 1B port of the switch component U4 is connected to the mixing module 103 via a resistor R21. The mixing module 103 is used to superimpose and adjust the gain voltages of Uin(2) to Uin(n) and the processed voltage of Uin(1) and to reverse the phase of the superimposed analog audio signal.

[0084] The output end of the mixing module 103 is connected to the analog inverse low-pass filter 8 via a resistor R11.

[0085] The analog inverse low-pass filter 8 comprises an operational amplifier U5, a resistor R11, a resistor R12, a capacitor C9, a capacitor C10 and a resistor R13, and is used for filtering audio signals and inverting the phase of audio signals.

[0086] The output of the filter 8 is connected to the output module (Uout) to output a high-quality mixed audio signal.

[0087] In one embodiment, when the circuit works normally, there is a certain working voltage range, and the common mode voltage providing circuit 10 can be used to provide the audio processing circuit 100100 with the common mode voltage required for operation. The common mode voltage providing circuit 10 may include an operational amplifier U1, a resistor R15, a resistor R18, and a capacitor C8, and its output Vcom is the common mode voltage required for the audio processing circuit 100 to work.

[0088] The working principle of the circuit is as follows: First, the voltage detector 2 dynamically obtains the peak voltage of the AC audio signal. The peak voltage of the AC audio signal is compared with the set threshold voltage, and the comparison result is output. If the peak voltage of the AC audio signal is greater than the comparison threshold voltage, the comparison result is that the input is a valid sound source. If the peak voltage of the AC audio signal is less than the comparison threshold voltage, the comparison result is that the input is an invalid noise sound source. The analog switch 4 detects that the control input is a valid sound source, the analog switch 4 of the valid input sound source Uin(1) link is turned on, Uin(1) participates in the mixing, the resistance of the digital adjustable potentiometer 6 of the Uin(2)~Uin(n) mixing link is continuously and quickly adjusted from a small resistor to a large resistor, and the gain of the Uin(2)~Uin(n) mixing link is quickly attenuated from 0dB to the set threshold negative gain to achieve audio ducking.

[0089] The analog switch 4 detects an invalid sound source as the control input, and the invalid input sound source Uin(1) link analog switch 4 is disconnected, Uin(1) does not participate in the mixing, and the adjustable potentiometer 6 resistance of the Uin(2)~Uin(n) mixing link is continuously and rapidly adjusted from a large resistor to a small resistor, and the Uin(2)~Uin(n) mixing link gain increases rapidly from the set threshold negative gain to 0dB. The invalid sound source noise of Uin(1) does not participate in the mixing, the circuit mixing output has lower noise, and the circuit mixing output signal-to-noise ratio is higher.

[0090] Please see Figure 4 , which is a schematic diagram of simulation results of the audio processing circuit 100 for automatically detecting effective sound sources and performing high-quality mixing processing according to an embodiment of the present application, Figure 3 The point where the Uin(1) signal is detected is used as the signal detection point, and the Uin(1) signal detection value is obtained as the peak voltage of the AC audio signal. With time as the horizontal axis and voltage amplitude as the vertical axis, the Uin(1), Uin(2), Uin(n), Uin(1) signal detection and the mixing output result Uout are compared and illustrated.

[0091] Within 0 to 30 ms, the Uin(1) signal is less than the preset voltage threshold, Uin(1) does not participate in the mixing, and the Uin(1) circuit background noise and small signal noise will not be injected into the mixing link, thus not lowering the signal-to-noise ratio of the mixing output.

[0092] Within 30 to 87 ms, when the Uin(1) signal is greater than the preset voltage threshold, Uin(1) participates in the mixing, and the Uin(2) to Uin(n) signals automatically duck. Therefore, during automatic ducking, the Uin(2) to Uin(n) signals participate in the attenuation of the mixing signal. At this time, Uout = Uin(1) + [Uin(2) + ... + Uin(n)] × k, where k is the attenuation coefficient.

[0093] The above-mentioned audio processing solution specifically involves the field of automatic detection of effective sound sources of analog audio with high-quality mixing. It supports the ducking function for automatic detection of effective sound sources of teaching microphones and high-quality mixing and low-latency local sound amplification of courseware sound sources. It supports the ducking function for automatic detection of effective sound sources of stage venue microphones and high-quality mixing and low-latency local sound amplification of promotional film sound sources. It supports the background music accompaniment function for automatic detection of effective sound sources of K-song room microphones and high-quality mixing and low-latency local sound amplification. It supports the ducking function for automatic detection of effective sound sources of Line in input and high-quality mixing and playback of local music playback by car high-fidelity audio processors.

[0094] Please see Figure 5 , which is an audio processing method of an embodiment of the present application, the method can be applied to Figures 1 to 4 In the application scenario of audio processing shown in , automatic detection of valid audio input device access and mixing of multiple audio inputs are realized. Invalid sound source noise does not participate in mixing, circuit mixing output noise is reduced, and the signal-to-noise ratio of mixing output is improved. The method includes the following steps:

[0095] Step 501: Acquire a peak voltage of a first audio signal, and compare the peak voltage with a preset voltage threshold to determine a voltage comparison result.

[0096] Step 502: When the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold, the first mixing link is controlled to be turned on, and the gain regulator 104 is controlled to reduce the gain of the second mixing link to a first threshold.

[0097] Step 503: when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, the first mixing link is controlled to be disconnected, and the gain regulator 104 is controlled to increase the gain of the second mixing link to a second threshold, which is greater than the first threshold.

[0098] In the above-mentioned audio processing method, the peak voltage of the first audio signal input by the first input module 101 is detected by the voltage detection module 105, and the peak voltage is compared with the preset voltage threshold. When the voltage comparison result is that the peak voltage is greater than the preset voltage threshold, the first audio signal is determined to be a valid sound source. At this time, the first mixing link is controlled to be turned on by the control module 106 so that the first audio signal participates in the mixing. At the same time, the gain of the second mixing link is adjusted to the first threshold through the gain regulator 104 to achieve audio ducking. On the other hand, when the voltage comparison result is that the peak voltage is less than the preset voltage threshold, the first audio signal is determined to be an invalid sound source. At this time, the first mixing link can be controlled to be disconnected by the control module 106 so that the invalid first audio signal does not participate in the mixing. At the same time, the gain of the second mixing link is adjusted to the second threshold through the gain regulator 104. In this way, the invalid sound source noise does not participate in the mixing, the circuit mixing output noise is reduced, and the signal-to-noise ratio of the mixing output is improved.

[0099] For a detailed description of the above audio processing method, please refer to the relevant description in the above embodiment. Its implementation principle and technical effect are similar and will not be repeated in this embodiment.

[0100] like Figure 6 As shown, this embodiment provides an electronic device 600, including: at least one processor 61 and a memory 62, Figure 6 A processor is taken as an example. The processor 61 and the memory 62 are connected via a bus 60. The memory 62 stores instructions that can be executed by the processor 61, and the instructions are executed by the processor 61 so that the electronic device 600 can execute all or part of the process of the method in the aforementioned embodiment to achieve automatic detection of valid audio input device access and mixing of multiple audio inputs. Invalid sound source noise does not participate in mixing, reducing the circuit mixing output noise and improving the signal-to-noise ratio of the mixing output.

[0101] In one embodiment, the electronic device 600 may be a network device such as a switch, a router, a gateway, etc., or may be a mobile phone, a tablet computer, a laptop computer, a desktop computer, or a large computing system composed of multiple computers.

[0102] The method provided in the embodiment of the present application can be implemented by the electronic device 600 executing corresponding software codes.

[0103] like Figure 7 As shown, this embodiment provides a mixer 700, including: the audio processing circuit 100 of any of the aforementioned embodiments, the mixer can be a separate mixing device, or it can be an accessory in an audio device, and at least has the same technical effect as the audio processing circuit 100 of the aforementioned embodiment. Please refer to the relevant description in the above embodiment. Its implementation principle and technical effect are similar, and this embodiment will not be repeated here.

[0104] An embodiment of the present application further provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the method of any of the aforementioned embodiments is implemented.

[0105] An embodiment of the present application also provides a computer program product, including a computer program, which implements the method of any of the aforementioned embodiments when executed by a processor.

[0106] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of modules is only a logical function division, and there may be other division methods in actual implementation, such as multiple modules can be combined or integrated into another system, or some features can be ignored or not executed.

[0107] The above-mentioned integrated module implemented in the form of a software function module can be stored in a computer-readable storage medium. The above-mentioned software function module is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to perform some steps of the methods of various embodiments of the present application.

[0108] It should be understood that the above-mentioned processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the application can be directly embodied as being executed by a hardware processor, or can be executed by a combination of hardware and software modules in the processor. The memory may include a high-speed RAM (Random Access Memory) memory, and may also include non-volatile storage NVM (Nonvolatile memory, NVM for short), such as at least one disk storage, and can also be a USB flash drive, a mobile hard disk, a read-only memory, a disk or an optical disk, etc.

[0109] The above storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The storage medium can be any available medium that can be accessed by a general or special computer.

[0110] An exemplary storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and the storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the storage medium can also exist as discrete components in an electronic device or a main control device.

[0111] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0112] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0113] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods of each embodiment of the present application.

[0114] In the technical solution of this application, the collection, storage, use, processing, transmission, provision and disclosure of user data and other information involved are in compliance with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0115] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An audio processing circuit, characterized in that: include: A first input module, used for inputting a first audio signal to be processed; A second input module, used for inputting a second audio signal to be processed; A mixing module connected to the first input module to form a first mixing link, the mixing module connected to the second input module to form a second mixing link, and used for mixing the first audio signal and the second audio signal; A gain adjuster, connected to the second input module, and used to adjust the gain of the second mixing link; a voltage detection module, connected to the first input module, configured to detect a peak voltage of the first audio signal, compare the peak voltage with a preset voltage threshold, and output a voltage comparison result; a control module, connected to the voltage detection module and the gain regulator, respectively, for controlling the first mixing link to be turned on and controlling the gain regulator to reduce the gain of the second mixing link to a first threshold value when the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold; The control module is further configured to, when the voltage comparison result shows that the peak voltage is less than the preset voltage threshold, control the first mixing link to be disconnected, and control the gain regulator to increase the gain of the second mixing link to a second threshold, where the second threshold is greater than the first threshold.

2. The circuit according to claim 1, characterized in that The control module comprises: a switch connected to the first mixing link, wherein when the switch is closed, the first mixing link is turned on, and when the switch is opened, the first mixing link is disconnected; The switch is used to control the switch to be closed when the voltage comparison result is that the peak voltage is greater than the preset voltage threshold.

3. The circuit according to claim 2, characterized in that The switch is further configured to control the switch to be disconnected when the voltage comparison result shows that the peak voltage is less than the preset voltage threshold.

4. The circuit according to claim 1, characterized in that The voltage detection module comprises: a voltage detector, connected to the first input module, and configured to detect a peak voltage of the first audio signal; A voltage comparator is connected to the voltage detector and the control module, and is used to compare the peak voltage with a preset voltage threshold and output a voltage comparison result to the control module.

5. The circuit according to claim 4, characterized in that The gain regulator includes: an adjustable potentiometer; the control module also includes: a controller; The controller is connected to the voltage comparator and is used to control the resistance of the adjustable potentiometer to increase to a first resistance value when the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold, so as to reduce the gain of the second mixing link to the first threshold.

6. The circuit according to claim 5, characterized in that The controller is further configured to control the resistance of the adjustable potentiometer to decrease to a second resistance value when the voltage comparison result shows that the peak voltage is less than the preset voltage threshold, so as to increase the gain of the second mixing link to the second threshold, and the second resistance value is less than the first resistance value.

7. The circuit according to claim 1, characterized in that Also includes: A filter, connected to the mixing module, for filtering the mixed audio output by the mixing module; And / or, an output module, connected to the filter, for outputting the mixed audio after filtering.

8. An audio processing method, characterized in that: Applied to the circuit according to any one of claims 1 to 7, the method comprises: Acquiring a peak voltage of the first audio signal, and comparing the peak voltage with a preset voltage threshold to determine a voltage comparison result; When the voltage comparison result shows that the peak voltage is greater than the preset voltage threshold, controlling the first mixing link to be turned on, and controlling the gain regulator to reduce the gain of the second mixing link to a first threshold; When the voltage comparison result is that the peak voltage is less than the preset voltage threshold, the first mixing link is controlled to be disconnected, and the gain regulator is controlled to increase the gain of the second mixing link to a second threshold, which is greater than the first threshold.

9. An electronic device, characterized in that: include: at least one processor; as well as a memory communicatively coupled to the at least one processor; The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the electronic device to perform the method of claim 8.

10. A sound mixer, characterized in that: The method comprises the audio processing circuit as claimed in any one of claims 1 to 7.

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