JPS61281786A - Video disk sound reproducer - Google Patents

Abstract

PURPOSE:To reproduce a sound according to a video signal by successively reproducing the first sound signal during a normal reproduction recorded on a disk, during the normal reproduction and successively reproducing the second sound signal during a special reproduction recorded on the disk, during the special reproduction. CONSTITUTION:A recording FM signal S6 detected from a video disk by a pickup circuit 15 is properly amplified by a preamplifier 16, FM demodulated 17, and a video signal and a sound FM wave are reproduced. A video signal S7 is reproduced as a standard color video signal in a next step video signal processing circuit 18. A sound FM wave signal S8 separates an FM carrier in a band pass filter 19 to demodulate 20 and obtain a digital sound signal S9, it is inputted to a data control circuit 22, by a control signal S10, a sound signal according to a reproducing mode (normal or special) is selected and reproduced.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a video disc audio playback device.

(Prior art) One of the characteristic features of video discs is 1x speed playback.
There are special playbacks such as slow motion playback. That is,
Various special reproductions are possible by kicking a signal detection light beam or sensor to the inner or outer periphery once or multiple times per revolution of the disk.

On the other hand, recording audio signals onto video discs.

Conventionally, it is common to FM-modulate two channels of analog audio signals and record them together with a video signal. For this reason, in the special playback mode, the sound has no meaning and has not been played back in the past.

(Object of the Invention) In view of the above, the present invention provides an apparatus for playing a video disc in which an audio signal for normal playback and an audio signal for special playback are recorded, in which even in the special playback mode, the audio An object of the present invention is to provide a video disc audio playback device that can play back video discs and audio.

(Structure of the Invention) In the video disc audio playback device of the present invention, a first audio signal during normal playback and a second audio signal during special playback are each converted into digital signals, and the digital signals are alternately arranged. The first or second audio signal is recorded on the audio channel, and the first or second audio signal is continuously reproduced depending on the reproduction mode.

(Function) During normal reproduction, the first audio signal recorded on the disc during normal reproduction is continuously reproduced, and during special reproduction, the second audio signal recorded on the disc during special reproduction is continuously reproduced.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

First, before explaining the audio reproducing apparatus, recording system signal processing for recording audio during normal reproduction and audio during double speed reproduction will be described with reference to FIG.

An analog audio signal S1 during normal playback inputted from a terminal 1 is converted into a digital audio signal S2 by an analog-to-digital converter (A/D converter) 5 and output to the array control section 6 at the first stage.

Further, the analog audio signal S3 inputted from the terminal 2 during double speed reproduction is converted into a digital audio signal S4 by the analog-to-digital converter 7, and is output to the array control section 6.

Assuming that the digital audio signal S2 described above is A and the digital audio signal S4 is B, the array control unit 6 outputs A, B, and A at regular intervals on the time axis as shown in FIG. 3(b).
The audio channels are arranged so that A, . . . are repeated alternately. The digital audio signals Sz and Sa arranged in this manner are subjected to processing such as adding an error correction signal in the digital modulator 8, then FM modulated in the FM modulator 9, and then sent to the next stage FM modulator IO. Output.

The video signal S5 input from the terminal 3 is subjected to color subcarrier low frequency conversion in the video signal processing section 11.

After processing such as pre-emphasis, it is output to the FM modulator 10, where each digital audio signal S,
, mixed with the S4 FM wave and recorded on the disc.
The signal S is modulated and output to terminal 4.

Figure 3 (al, (bl) and Figure 4 show the above relationships, and Figure 4 shows the video signal in Figure 3 (a) and the digital audio signals A and B in Figure 3 (b). It is a spectrum distribution diagram when recording.

This will be explained with reference to FIG. 5 regarding recording on the disk surface.

Now, the digital data blocks of audio A during normal playback on the n) rack are A, , , An-2+, respectively.
An-: l... and similarly, the digital data blocks of audio B during special playback are each Bfl-1+Bn.
-21Bn-3..., the digital audio arrangement on n tracks is An-+ + Bn-1+
An-z +tL-z l...A 11-m r
It becomes 13 nm.

In the above description, the two audio channels A and B were described as audio during normal playback and audio during double speed playback, but triple speed playback is used as special playback.

It is also possible to record audio at quadruple speed 1, etc.

Furthermore, if a frequency band that allows multi-channel recording is selected as the recording channel, it is possible to record not only the sound during normal playback but also the sound at double speed, triple speed, quadruple speed, etc. at the same time.

Next, let's talk about an audio playback device for video discs on which audio signals are recorded using the signal processing described above.

This will be explained with reference to FIG.

The recorded FM signal S6 detected from the video disc by the pink-up circuit 15 is appropriately amplified by the 5 preamplifier 16, and FM demodulated by the FM demodulator 17, thereby reproducing the video signal and audio FM wave shown in FIG. 4 above. be done.

The video signal S7 is subjected to dropout correction, color converter, and time base correction in the primary stage video signal processing circuit 18, and then reproduced as a standard color video signal.

On the other hand, the audio FM wave signal SIl is separated into FM carriers by a bandpass filter 19 and demodulated by an FM demodulator 20 to obtain a digital audio signal S9.

This digital audio signal S is transmitted to the digital demodulator 21
After processing such as error correction, the data is output to the data control circuit 22.

The data control circuit 22 receives a control signal S from a terminal 24. selects and reproduces an audio signal according to the reproduction mode. In other words, during normal playback,
A, 1-+, AI, -z, A-z "An-
m + A (noll-1+ A (11011-2
+A +11111-3...'A(null-6 is selected and reproduced, converted to analog audio signal S11 by the digital/analog converter 23, and outputted to the output terminal 25.Similarly, in the special playback mode, + BR-1+ B1
1-2 + B11-3 ”' B n-m + B
(n+11-1 +B(noll-! l B+l,
-3...Bo. 1. -1 and play the digital
The analog converter 23 converts it into an analog audio signal S, and outputs it to the output terminal 25.

(Effects of the Invention) As described above, according to the video disk audio reproducing apparatus of the present invention, it is possible to reproduce audio according to a video signal not only during normal playback but also in special playback mode.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram of a video disk audio reproducing apparatus of the present invention, FIG. 2 is a schematic block diagram showing signal processing of the recording system, and FIGS. FIG. 4 is a diagram showing the spectral distribution of the video signal and digital audio signal, and FIG. 5 is a diagram showing the arrangement of audio signals recorded on a video disc. 15...Pickup circuit 16...Preamplifier 17...FM demodulator 18.
...Video signal processing section 19...Band pass filter 20...FM demodulator 21...Digital demodulator 22...Data control circuit 23...Digital-to-analog converter Fig. 3 Fig. 4 F @SIL huan g5 figure reproduction 75 direction

Claims (1)

[Claims] 1) The first audio signal during normal playback and the second audio signal during special playback are each converted into digital signals, and these digital signals are alternately arranged and recorded on the audio channel, depending on the playback mode. A video disc audio reproducing device characterized in that the first or second audio signal is continuously reproduced.