The audio processing equipment of gain automatic control device, method and application thereof and earphone
Technical field
The present invention relates to a kind of Gain Automatic device and method, relate in particular to a kind of sound gain automatic control device, it uses the hardware of lesser number to constitute and can control a sonorific volume automatically.
Background technology
Recently, being used more and more widely such as MP3, Walkman and mobile phone by people, but in music appreciating, conversation, our ear is also bearing damage in various degree.
Therefore, a kind of Gain Automatic control technology occurred, can control the hearing of the volume of sound-producing device output sound with the protection user.On July 16th, 2003, disclosed Chinese No. 02119372 patent provided the method for a kind of automatic gain controller and output control signal thereof, and this automatic gain controller comprises an estimator, is used to estimate the level of input signal; A subtracter is used to calculate by the level of described estimator estimation and the difference between the predetermined reference value; And a gain controller, by exporting controlling value to doing non-linear ratio's conversion by the difference of described subtracter output.Though above-mentioned technology has reached the purpose of automatic control signal gain, complex structure.
Summary of the invention
In view of this, the invention provides a kind of automatic gain output device, particularly a kind of gain automatic control device is with protection hearing, and simplifies the hardware configuration of described device.
In view of this, the invention provides a kind of automatic gain output device, particularly a kind of gain automatic control device that uses the hardware formation of lesser number.
Described gain automatic control device, it comprises an input port and an output port, described gain automatic control device also comprises: a multicircuit switch, be connected an attenuator circuit with input port, be connected with multicircuit switch and output port, comprise a plurality of decay branch roads, each decay branch road is used for the signal from input port input is carried out in various degree decay; One signal sampling circuit links to each other with output port, is used for obtaining sampled signal from output port; One analogue-to-digital converters, be connected with sample circuit and multicircuit switch respectively, be used for converting sampled signal to digital quantity from analog quantity, this digital quantity control multicircuit switch choose respective branch transmission in the attenuator circuit from the signal of input port input to output port.
Described automatic gain control equipment, each decay branch road is serially connected with the resistance of different resistances respectively in the attenuator circuit, and this resistance makes from the signal respective attenuation of input port input.
A kind of auto gain control method is provided simultaneously, and its step comprises: the sampled signal that obtains an output port; Convert described sampled signal to digital quantity from analog quantity; Utilize described digital quantity sampled signal to control a multicircuit switch and select a respective attenuation branch road; Utilize the transmission of described multicircuit switch and described decay branch road from the signal of input port input to output port.
Compared to prior art, described AGC (automatic gain control) system avoids the output sound volume excessive in the automatic control that realizes output volume, uses hardware configuration still less when reaching the purpose of protecting hearing, is convenient to implement.
The present invention provides an audio processing equipment simultaneously, described audio processing equipment comprises: an audio decoder is decoded to being stored in a storage device sound intermediate frequency file, it is simulated audio signal that one D/A conversion unit is used for described decoded digit audio frequency conversion of signals, and the simulated audio signal after the audio frequency amplifier logarithmic mode converting unit conversion amplifies; Simulated audio signal output after one audio output port will amplify.Described audio processing equipment also comprises a gain automatic control device, described gain automatic control device is connected between audio frequency amplifier and the audio output port, audio signal after the amplification is input to described gain automatic control device, described audio signal is sampled, and carry out integral processing, according to the integral processing result described audio signal is adjusted, exported adjusted audio signal to described audio output port.Audio signal can be regulated output sound automatically by gain automatic control device before the described audio processing equipment of output volume.
The present invention provides an earphone simultaneously, comprises an input, it imports audio electrical signal; One loudspeaker are sound wave with audio signal by electrical signal conversion.Described earphone also comprises a gain automatic control device, and described input, gain automatic control device, loudspeaker link to each other successively; Audio signal is input to described gain automatic control device through input and handles, described audio signal is sampled, and carry out integral processing, described audio signal is adjusted according to the integral processing result, export adjusted audio signal to described loudspeaker, audio signal is converted to sound wave.Can also once add a line control machine on described earphone, the user can also be by regulating the volume of the manual control loudspeaker output of this line control machine.The earphone that includes described gain automatic control device, the volume that can regulate output sound automatically.
Description of drawings
Fig. 1 is the circuit block diagram in gain automatic control device one execution mode of the present invention.
Fig. 2 is ordinary audio treatment facility modular structure figure.
Fig. 3 is the modular structure figure in sound intermediate frequency treatment facility one execution mode of the present invention.
Fig. 4 is the modular structure figure of earphone first execution mode among the present invention.
Fig. 5 is the modular structure figure of earphone second execution mode among the present invention.
Fig. 6 is the modular structure figure in machine the 3rd execution mode among the present invention.
Embodiment
As shown in Figures 1 and 2, the two-way audio signal enters a multicircuit switch 13 via the input port (including a first input end 10a and one second input 10b) of gain automatic control device 1 respectively.This multicircuit switch 13 has two output port groups 2 and 3, is respectively applied for transmitting two paths audio signal to an attenuator circuit 14.Attenuator circuit 14 has two decay branch road groups 6 and 7, respectively the output port group 2 and 3 of corresponding multicircuit switch 13.The two-way audio signal carries out exporting to respectively after the decay of respective degrees the output port (including one first output 15a and one second output 15b) of gain automatic control device 1 via these two decay branch road groups 6 and 7.
One signal sampling circuit 11 obtains the sampled signal of output two-way audio signal and carries out integral processing from first and second output 15a, 15b; Sampled signal after 12 pairs of described integral processing of one analogue-to-digital converters carries out the conversion of analog quantity to digital quantity.
In execution mode shown in Figure 1, in advance the sampled signal analog quantity is divided into by size 4 numerical value sections: numerical value section 1,2,3 and 4, corresponding with it 4 digital quantities (with Binary Zero and 1 expression) that after analogue-to-digital converters 12 conversions, produce: 00,01,10,11.When certain sampled signal falls into a certain numerical value section of analog quantity, analogue-to-digital converters 12 produce a corresponding digital amount according to this numerical value section, this digital quantity inputs to multicircuit switch 13 via the two control end groups 4 and 5 of multicircuit switch 13, and the disconnection of these digital quantity control multicircuit switch 13 each ports of output group or conducting state utilize 14 pairs of audio signals from first, second input 10a, 10b input of attenuator circuit to carry out respective attenuation.
Corresponding four groups of sampled signal digital quantities from 4,5 inputs of two control end groups, multicircuit switch 13 output port groups 2 have four output ports 21,22,23 and 24, and output port group 3 has four output ports 31,32,33 and 34.Output port group 2 is connected a decay branch road of attenuator circuit 14 with 3 each output port.Each decay branch road is not connected in series or is connected in series resistance element R1, R2 and the R3 that resistance does not wait, with this audio signal of transmitting is carried out in various degree decay.According to the sampled signal digital quantity of each reception, multicircuit switch 13 is chosen from different output port transmitting audio signals to different decay branch roads.
Control the conducting or the disconnection of multicircuit switch 13 each output port of output group from the sampled signal digital quantity of multicircuit switch 13 control end groups 4 and 5 inputs.Concrete control relation such as following table:
41,42 inputs |
Output |
00 |
21 conductings 22,23,24 disconnect |
01 |
22 conductings 21,23,24 disconnect |
10 |
23 conductings 21,22,24 disconnect |
11 |
24 conductings 21,22,23 disconnect |
51,52 inputs |
Output |
00 |
31 conductings 32,33,34 disconnect |
01 |
32 conductings 31,33,34 disconnect |
10 |
33 conductings 31,32,34 disconnect |
11 |
34 conductings 31,32,33 disconnect |
Below illustrate, for example, if certain sampled signal analog quantity size falls into numerical value section 2, then produce digital quantity 01 after analogue-to-digital converters 12 conversions, this digital quantity 01 is sent to the two control end groups 4 and 5 of multicircuit switch 13 simultaneously.Two control ends 41 of control end group 4 and 42 receive digital quantity 01; Two control ends 51 of control end group 5 and 52 receive digital quantity 01.4 controls of control end group are carried out respective attenuation from the audio signal of first input end 10a input attenuator circuit 14 decay branch road groups 22,5 controls of control end group are carried out respective attenuation from the audio signal of second input 10b input attenuator circuit 14 decay branch road groups 32.
Obviously the sampled signal analog quantity is not limited to be divided into 4 numerical value sections by size, can be any even number.By the adjustment of variable connector 13, realized automatic control to original input audio signal gain.
As shown in Figure 2, be audio processing equipment under the prior art.Described audio processing equipment comprises: a central processing unit 100, and it can obtain to press the audio documents of certain coded format storage from a storage device 103; 105 pairs of described audio documents of one audio decoder are decoded, and generate digital audio and video signals; One digital to analog converter 106, the digital audio and video signals of audio decoder being adorned device 105 decodings is converted to simulated audio signal; One audio frequency is put device 107, is used for amplifying described simulated audio signal, and by the simulated audio signal after an audio output port 108 output amplifications.Audio processing equipment generally also includes: a communication interface 102, be used for being connected with equipment such as outer computer, and obtaining the audio documents of outer computer, and be stored in this storage device 103; One input unit 104, the user can send operational order to central processing unit 100 by this input unit 104, for example play, a last head, next, stop and volume adjusting etc.; One display unit 101 is used to show the relevant information of audio processing equipment.
Figure 3 shows that the audio processing equipment that has increased Gain Automatic controlled function.This audio processing equipment has added a gain automatic control device 1, described gain automatic control device 1 places between audio frequency amplifier 107 and the audio output port 108, analog signal is input to first input end 10a and the one second input 10b of gain automatic control device 1 after amplifying through audio frequency amplifier 107, and exports after 1 gain is controlled automatically through gain automatic control device again.Before this audio processing equipment of audio signal output,, can reach automatic control output volume effect through described gain automatic control device 1.
Be illustrated in figure 4 as first execution mode of the earphone that increases Gain Automatic controlled function.This earphone comprises signal one input 201, a gain automatic control device 1 and loudspeaker 200.Simulated audio signal is input to gain automatic control device by input 201, afterwards by loudspeaker 200 audio signal is converted to sound wave through the Gain Automatic control of 1 pair of gain automatic control device.As shown in Figure 5, increased by second execution mode of the earphone of Gain Automatic controlled function, this earphone is different with first embodiment to be also to comprise a line control machine 203, and this line control machine 203 is connected between loudspeaker 200 and the gain automatic control device 1.The user can be by regulating the gain of these line control machine 203 manual adjustments audio signals.As shown in Figure 6, be the earphone among the 3rd embodiment, the different line control machines 203 that are with second embodiment of this earphone are connected between input 201 and the gain automatic control device 1.