JPS5890888A - Signal recording and reproducing system - Google Patents

Abstract

PURPOSE:To record audio information together with video information without extending a frequency band, by inserting a PCM audio signal and FM-modulating the signal to each blanking period of a luminance signal and a carrier chrominance signal to be low-frequency-converted. CONSTITUTION:A stereo audio signal is pulse-code-modulated at PCM modulation circuits 2, 3. The PCM audio signal from the circuit 2 is applied to a synthesizer 4. A video signal is applied to a luminance/chrominance separation circuit 6, the separated luminance signal is applied to the synthesizer 4 and the PCM audio signal is inserted at a horizontal blanking period of the luminance signal. After the output of the synthesizer 4 is modulated in an FM modulation circuit 7, it is applied to a synthesizer 8. Further, the carrier chrominance signal is frequency-converted at a frequency conversion circuit 11 and after insertion the PCM audio signal which is delayed in the horizontal blanking period, applied to the synthesizer 8. The output of the synthesizer 8 is modulated at a PWM modulation circuit 12 and recorded on an optical recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording method for recording audio information together with video information on a recording medium, and a reproduction method for reproducing the recorded information.

Conventional recording methods for recording audio information along with the FM information include the following: ・The Eiso signal and the audio signal are each recorded as FNII, and both signals labeled FMt are weighted. and record it on the recording medium.

■ FM tune the Eirin signal, convert the audio into a PCM audio signal with a lower frequency than the FMt-frequency band, superimpose these signals, convert them into *PWM signals, and send this to the recording medium. to be recorded. (2) A PCM signal of the audio signal is inserted into the blanking period of the video signal, and the video signal into which the PCM audio signal has been inserted is FM-modified and recorded.

Since the recording method (2) does not apply PCM to the audio signal, there are problems in terms of compensation for 8/N of the audio signal and dropout. Since the reproduction method (2) adopts PCM for the audio signal, there is no problem with the reduction of 87N or compensation for dropouts, but interleaving etc. is applied to the PCM audio signal in consideration of compensation for dropouts. Therefore, the number of pits of the PCM audio signal increases and the frequency band used becomes wider.The playback method of @■ cannot widen the frequency band used for the PCM audio signal, so it is necessary to compensate for dropouts. Therefore, it is difficult to perform interleaving or the like on the PCM audio signal to compensate for dropouts.

In view of this, the main object of the present invention is to record audio information together with video information on the same recording track of a recording medium using a signal recording method and a nuclear recording method that can record audio information without expanding the frequency band used. This paper attempts to propose a reproduction method that can easily reproduce video information and audio information from signals recorded on a medium. Another object of the present invention is to propose a signal reproduction method that makes it possible to compensate for dropouts even though audio information is recorded on the same recording track of a recording medium as well as video information. Still another object of this book is to propose a signal recording method that can record multiple channels of audio information along with video information on the same recording track of a recording medium without expanding the frequency band used.

The present invention of tJtl is concerned with a signal distribution method,
Separating the video signal into a luminance signal and a carrier color signal,
This carrier color signal is subjected to low frequency conversion, and the first and second PCs are used during each blanking period of the luminance signal and the low frequency converted carrier color signal.
The M audio signals are inserted respectively, and the luminance signal into which the first PCM audio signal is inserted is FMll'1iiL, and this FM
A first composite signal consisting of a modulated signal and a second composite signal consisting of a low frequency converted carrier color signal into which a PCM audio signal is inserted.''2
A synthesized signal of #10 composite signal consisting of the FM modulated signal of the luminance signal with the inserted signal and #! in the blanking period. The superimposed signal is reproduced from a recording medium on which a second synthesized signal consisting of a low-frequency converted carrier color signal into which the PCM audio signal of No. 2 is inserted is superimposed, and w, 1, and The composite signal of tJL2 is separated, the first composite signal is FM demodulated, and the t! Separating the luminance signal and the first PCM audio signal from the FM de-output of the composite signal of jL1, and separating the low-frequency converted carrier color signal and the second PCM audio signal from the second composite signal, This low frequency converted carrier color signal is inversely converted to the original carrier color signal.

Embodiments of the present invention will be explained below with reference to the figures.

Figure 1 is a block diagram of an example of a signal recording device to which the signal distribution method of the present invention is applied, and FIG. 2 is a block diagram of an example of a signal reproducing device to which the signal reproducing method of the present invention is applied. First, start from the signal recording device shown in Figure 1 to the station. (1
1 is an audio signal input terminal. This audio signal is a stereo audio signal consisting of left and right audio signals, I'L. This stereo audio signal is transmitted to the first and second PCM modulation circuits (2
+ , (supplied to 31, where the first and #20P
CM strange p! Circuit (2).

The audio signals supplied in (3) are the first and second audio signals, respectively, and here they are the same stereo audio signals as fit. These first and second PCM cost tuning circuits).

In (3), each tJLl and the second audio signal are converted into PCM, and an error correction code such as chcc and a synchronization bit signal are inserted. Note that the video signal from the input terminal (5) is supplied to the synchronization separation circuit I, and the obtained synchronization signal (horizontal synchronization signal) is supplied to the clock signal generator aS.

This clock signal generator (clock signal from IS
CM cost tuning circuit), (supplied to 31).

The first PCM audio signal from the first PCM flight p1 plane (2) is supplied to the synthesizer (4). The video signal from the video signal input terminal (5) is transmitted to the luminance-chromaticity separation circuit (6).
) and the separated luminance signal is sent to the synthesizer (4)
The above-mentioned first PCM audio signal is inserted into the horizontal blanking period of the luminance signal. This synthesizer (4) will be used at the station with reference to FIG. 3A. FIG. 3A shows the waveform of the luminance signal, which has a vertical blanking period T(HH) of about 10 μsec. Note that sH indicates the horizontal synchronization signal that should be present.

This horizontal blanking period T (HB) corresponds to approximately 35 pits when converted into the number of pits. Then, the above-mentioned first PCM audio signal is inserted into this horizontal blanking period. In this case, the number of pits for the left and right audio signals and R is 10 bits each, and the number of pits for the synchronization and error correction signals is 3, so that a total of 23 bits are co-interpolated.

The output from the synthesizer (4) is supplied to the FM modulation circuit (7), which outputs the first valley signal.
The combined signal is supplied to the combiner (8).

Second PCM conversion sound from the 20th PeM modulation circuit (3)
The pa signal is passed through a delay circuit (9) for dropout compensation.
) to the combiner Ql.

The carrier chrominance signal from the luminance signal-chromaticity signal separation circuit (6) (
The carrier wave frequency is 3.58 MHz) is supplied to the frequency conversion circuit Qll, where it is low-band converted into a carrier color signal with a carrier wave frequency of 688 kHz, and the low-band converted carrier color signal is supplied to the combiner αυ, and this The above-mentioned delayed second PCM audio signal is inserted into one horizontal blanging period of the carrier color signal to be low-band converted, and the second synthesized signal is outputted from this.

This synthesizer (1(1)) will be used at the station with reference to FIG. 3. FIG.
・This horizontal synchronization signal section 'r (sH) is approximately 13
Comparable to Pitt. And this horizontal synchronization interval T(8
A second PCM audio signal is inserted into H). That PCM
As for the encoded audio signal, 5 bits are allocated to each of the left and right audio signals, 5 bits are allocated to R, and 1.5 pits are allocated to the error correction code and P1+ period signal, and a total of 11.5 bits are co-inserted.

The second combined signal from the combiner is supplied to the combiner (8) and added to the above-mentioned first combined signal, and the added output is supplied to the PWMtl11 circuit a3, and its output terminal ( A recording signal is supplied to 13. This distribution signal is recorded on an optical recording medium using an optical recording device, for example. , bFi is the band line of the carrier chrominance signal subjected to low frequency conversion, CFi is the band line of the FM modulated brightness signal, dl
and e respectively show the bands of the first and second PCM audio signals. Note that the horizontal axis represents frequency (MHz), and the vertical axis represents level (dB).

Next, with reference to FIG. 2, the signal reproduction is performed between stations.

Alternatively, it is an input terminal for a reproduction signal reproduced from an optical recording medium using, for example, an optical signal reproduction device.゛This reproduced signal is supplied to the iPWM demodulation circuit (11, and its damaged frame output is supplied to the Hynos filter ■ and the low-pass filter eυ. The first synthesized signal from the I-pass filter (FIG. ) The luminance signal obtained from this separation circuit is supplied to the synchronization forming circuit (24), where the first PCM audio signal that was inserted into the luminance signal is replaced with a horizontal synchronization signal, and the luminance signal obtained by this separation circuit is The combined luminance signal is supplied to the combiner (c).

The output from the low-pass filter CI) is the color If flaw signal PC
The signal is supplied to the M signal separation circuit (A). The low frequency converted carrier color signal obtained from the separation circuit (c) is supplied to the frequency exclusion circuit fin and is inversely converted to the original carrier color signal having a carrier wave frequency of 3.58 MHz. (to) is a PLL circuit that generates a local oscillation signal of 4.27 MHz to be supplied to this frequency conversion circuit.

In addition, the luminance signal from the separation circuit is supplied to the synchronization separation circuit (i@), and the horizontal and vertical 11 synchronization signals obtained from this circuit are sent to the synchronization shaping circuit (infrared). ).

The gate signal for extracting the PCM audio signal created by this circuit is supplied to the @ of the separation circuit.The carrier color signal of 3.58 MHz obtained from the frequency conversion circuit is sent to the color process circuit (to). supplied to

The burst flag signal from the circuit is then supplied to the process circuit (7). The signal is then supplied to the iIs color forwarding/positioning signal generator (c) from the process circuit (to), added to the above-mentioned luminance signal, and then supplied to the picture processing circuit 011. (2) In addition, the first and second PCM-converted audio signals obtained from the separation circuits @ and @ are respectively output after PCM.

*1 and the second audio signal obtained respectively are supplied to the error compensation circuit (to) and demodulated.
When a dropout occurs, for example, 0 (to) that compensates the first audio signal with the second audio signal is the output terminal of the error compensation circuit (c), and this terminal CIb1K
In the embodiment described above, the same stereo audio signal was used as the first and second audio signals, but instead, the first audio haiku was output as the left audio signal L (or the right audio signal). R), the second audio signal can also be the right audio signal R (or the left audio signal L). Alternatively, the first audio signal is the left and right audio signal, and the sum of l-L, that is, the sum signal (L+ft), and the second audio signal is the left and right audio signal, and the RO difference signal (L-)t). Alternatively, the front left, rear left, front right, and far right audio signals of the 4-channel stereo audio signal may be matrixed to form a 2-channel composite audio signal, and each of the 4-channel stereo audio signals may be
It may also be an audio signal.

According to the first invention described above, it is possible to develop a signal recording method that can record audio information together with video information on the -1- recording track of a recording medium without increasing the frequency band used. ◎ According to the second invention, the above-mentioned signal recording method can be used as a recording medium! ? It is possible to obtain a signal reproduction method that can easily reproduce video information and audio 'ps+W information from a reproduced signal of a recorded signal.

Further, according to the first aspect of the present invention, by using the same audio signal as the above-mentioned first and second audio signals, there is provided a signal recording method that allows dropout compensation without expanding the frequency band used. can be obtained.

According to the first aspect of the present invention, it is possible to obtain a signal recording method that can record audio information of multiple channels together with audio information on the same recording track of a recording medium without expanding the frequency band used. I can do it.

As long as the above-mentioned signal recording and reproducing methods can be applied, it is not limited to optical recording and reproducing methods, but also magnetic recording and reproducing methods, capacitive recording and reproducing methods, piezoelectric recording and reproducing methods, etc. .

[Brief explanation of the drawing]

Claims (1)

[Claims] 1. Separating the video signal into a luminance signal and a carrier chrominance signal, and converting the carrier chrominance signal into a low frequency band, and in each blanking period of the luminance signal and the carrier chrominance signal to be low frequency converted. , the 11th and second PCM audio signals are respectively inserted, and the luminance signal into which the #1 PCM audio signal has been inserted is F Mrllil L
, the synthesized signal of the building consisting of the covered FM modulated signal, and the above #
! 2. A signal recording method characterized in that a synthesized signal of signal 2 consisting of a low-frequency converted carrier color signal into which a PCM audio signal of signal 2 is inserted is superimposed and recorded on a recording medium. 2. A first composite signal consisting of a #FM modulated signal of a luminance signal into which a first PCM audio signal is inserted during a blanking period, and a low-frequency band into which a second PCM audio signal is inserted during a blanking period. The superimposed signal is reproduced from the recording medium on which the composite signal of body 2 consisting of the converted carrier color signal is superimposed and recorded, the superimposed signal is separated from the first and #20 composite tubes, and the first composite signal is The signal is FMQ modulated, and the above jf degree signal and the above II P are obtained from the FM@@ output of the first composite signal.
The CM audio signal is separated, and the low frequency converted carrier color signal and the second PCM audio signal are separated from the second composite signal, and the 1# low frequency w! A child's name reproduction method that is characterized by reversing the cost-conveyed color signal to the original color signal.