CN107613382A - The PCM mode audio synthesis systems of television set - Google Patents

Abstract

The invention discloses the PCM mode audio synthesis systems of television set, including clock oscillator, control device, speech memory, address counter, decoding circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device, the control device, speech memory, address counter are connected with clock oscillator respectively, and the speech memory, address counter, decoding circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device are sequentially connected；The different clock signals that the clock oscillator is used for required for producing in television set.The present invention provides clock signal to control device, speech memory, address counter simultaneously by same clock oscillator, it ensure that control device, speech memory, the uniformity of three devices of address counter, it ensure that the real-time of audio synthesis system, carry out the decompression of data in the case where reducing distortion rate by decoding circuit again, ensure that higher discrimination.

Description

The PCM mode audio synthesis systems of television set

Technical field

The present invention relates to tv audio system, and in particular to the PCM mode audio synthesis systems of television set.

Background technology

TV (Television, TV, Video) refers to the image frame and audio using electronic technology and equipment transmission activity Signal, i.e. television receiver, and important broadcast and video communication instrument, television set is earliest by Britain engineer John Lip river Lucky Baird is invented in nineteen twenty-five.The visual pattern of TV electronically transmission activity immediately.It is similar with film, TV profit Show the rest image of a frame frame gradual change with the persistence of vision effect of human eye, form visual live image.Television system is sent out It is order transmission after electric signal that each fine fraction of scenery is pressed brightness and chroma conversion by sending end.In receiving terminal by corresponding several What position shows brightness and the colourity of each fine fraction to reappear view picture original image.The progress of science and technology, is that TV is rapid One major reason of popularization.Various countries' TV signal scanning standard and channel broadband are incomplete same, are seeked advice from by international wireless electricity The suggestion of the committee (CCIR) is distinguished with the Latin alphabet.Audio synthesis system of the prior art can not have concurrently discrimination and Real-time two advantages.

The content of the invention

The technical problems to be solved by the invention be audio synthesis system of the prior art can not have concurrently discrimination and Real-time two advantages are, and it is an object of the present invention to provide the PCM mode audio synthesis systems of television set, in the case where realizing higher discrimination Realize the advantages of real-time.

The present invention is achieved through the following technical solutions：

The PCM mode audio synthesis systems of television set, including clock oscillator, control device, speech memory, address meter Number device, decoding circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device, the control device, voice Memory, address counter are connected with clock oscillator respectively, the speech memory, address counter, decoding circuit, digital-to-analogue Converter, low pass filter, audio-frequency amplifier, audio output device are sequentially connected；The clock oscillator is used to produce TV Different clock signals required in machine；The control device is used to be turned on and off audio synthesis system, and the voice is deposited Reservoir is used to store voice data, and the decoding circuit is used to composite colour television signal restoring former tristimulus signals, described Digital analog converter is used to digital audio and video signals being converted into simulated audio signal, and the low pass filter is used to filter out less than cut-off The signal of frequency is by the way that the audio amplification signal is used for the amplification of audio signal, and the audio output device is used for sound Output.

Clock generator produces concussion by elements such as extraneous resistance, electric capacity, brilliant battle arrays, by internal oscillating circuit, during generation Clock signal, the clock signal needed for each several part is produced after signal is divided by frequency divider all the time, to realize the clock of each several part It is synchronous.The working condition of control section each several part, sequential logic etc. are controlled.Audio-frequency information honor in the form of digital code is placed on In audio ROM, caused digital code after being stored in usual audio ROM and non-audio signals directly quantify, but by this Digital code is stored in audio ROM after being compressed.

Decoded portion is for recovering the digital code after these compressions, and it is by compressing and converting into natural code, Ran Houtong Cross D/A converter and convert digital signals into analog signal, that is, regenerate the audio signal recorded.Obtain the sound of high quality Sound, it is necessary to area is carried out to the output signal of D/A converter and is made an uproar processing, i.e., by a low pass filter, is then put with audio Big device amplifies the voice signal of synthesis, is exported by loudspeaker.The present invention gives control dress simultaneously by same clock oscillator Put, speech memory, address counter offer clock signal, ensure that control device, speech memory, address counter three The uniformity of device, the real-time of audio synthesis system is ensure that, then entered by decoding circuit in the case where reducing distortion rate The decompression of row data, it ensure that higher discrimination.

Further, the decoding circuit includes luminance channel, decoding matrix, chrominance channel and the subcarrier being sequentially connected Restoring circuit, the luminance channel are used to separate the luminance signal in composite colour television signal, carry out broadband amplification, Realize brightness and contrast's control；The chrominance channel is used for the extraction of chrominance signal, obtains tristimulus signals；The subcarrier Restoring circuit is used to provide reflection carrier chrominance signal strong and weak half-line frequency identification signal.

Further, what the speech memory stored is the digital code after overcompression.

The present invention compared with prior art, has the following advantages and advantages：The present invention is shaken by same clock Swing device while provide clock signal to control device, speech memory, address counter, ensure that control device, phonetic storage The uniformity of three device, address counter devices, the real-time of audio synthesis system is ensure that, then reduced by decoding circuit The decompression of data is carried out in the case of distortion rate, ensure that higher discrimination.

Brief description of the drawings

Accompanying drawing described herein is used for providing further understanding the embodiment of the present invention, forms one of the application Point, do not form the restriction to the embodiment of the present invention.In the accompanying drawings：

Fig. 1 is schematic structural view of the invention.

Embodiment

For the object, technical solutions and advantages of the present invention are more clearly understood, with reference to embodiment and accompanying drawing, to this Invention is described in further detail, and exemplary embodiment of the invention and its explanation are only used for explaining the present invention, do not make For limitation of the invention.

Embodiment

As shown in figure 1, the PCM mode audio synthesis systems of television set, including clock oscillator, control device, voice are deposited Reservoir, address counter, decoding circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device, the control Device processed, speech memory, address counter are connected with clock oscillator respectively, the speech memory, address counter, solution Code circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device are sequentially connected；The clock oscillator is used Different clock signals required for producing in television set；The control device is used to be turned on and off audio synthesis system, The speech memory is used to store voice data, and the decoding circuit is used to composite colour television signal restoring former three primary colours Signal, the digital analog converter are used to digital audio and video signals being converted into simulated audio signal, and the low pass filter is used to filter Go out the signal less than cut-off frequency by the way that the audio amplification signal is used for the amplification of audio signal, the audio output device Output for sound.Luminance channel, decoding matrix, chrominance channel and the subcarrier that the decoding circuit includes being sequentially connected are extensive Compound circuit, the luminance channel are used to separate the luminance signal in composite colour television signal, carry out broadband amplification, real Existing brightness and contrast's control；The chrominance channel is used for the extraction of chrominance signal, obtains tristimulus signals；The subcarrier is extensive Compound circuit is used to provide reflection carrier chrominance signal strong and weak half-line frequency identification signal.The speech memory storage is through overcompression Digital code afterwards.

Above-described embodiment, the purpose of the present invention, technical scheme and beneficial effect are carried out further Describe in detail, should be understood that the embodiment that the foregoing is only the present invention, be not intended to limit the present invention Protection domain, within the spirit and principles of the invention, any modification, equivalent substitution and improvements done etc., all should include Within protection scope of the present invention.

Claims (3)

1. the PCM mode audio synthesis systems of television set, it is characterised in that including clock oscillator, control device, phonetic storage Device, address counter, decoding circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device, the control Device, speech memory, address counter are connected with clock oscillator respectively, the speech memory, address counter, decoding Circuit, digital analog converter, low pass filter, audio-frequency amplifier, audio output device are sequentially connected；The clock oscillator is used for Produce the different clock signals required in television set；The control device is used to be turned on and off audio synthesis system, institute Predicate acoustic memory is used to store voice data, and the decoding circuit is used to composite colour television signal restoring former three primary colours letter Number, the digital analog converter is used to digital audio and video signals being converted into simulated audio signal, and the low pass filter is used to filter out Signal less than cut-off frequency is used for by, the audio amplification signal amplification of audio signal, and the audio output device is used In the output of sound.

2. the PCM mode audio synthesis systems of television set according to claim 1, it is characterised in that the decoding circuit Including luminance channel, decoding matrix, chrominance channel and the subcarrier regenerator being sequentially connected, the luminance channel is used for coloured silk Luminance signal in color composite video signal is separated, and is carried out broadband amplification, is realized brightness and contrast's control；The colourity Passage is used for the extraction of chrominance signal, obtains tristimulus signals；The subcarrier regenerator is used to provide reflection carrier chrominance signal Strong and weak half-line frequency identification signal.

3. the PCM mode audio synthesis systems of television set according to claim 1, it is characterised in that the phonetic storage What device stored is the digital code after overcompression.