JPS62150983A - Recording and reproducing device for television signal - Google Patents

Abstract

PURPOSE:To record and reproduce plural standard television signals without changing a recording and reproducing means by providing the first recording and reproducing mode to record and reproduce plural standard television signals and the second one to record and reproduce a high definition television signal. CONSTITUTION:The two standard television signals are supplied to a timing adjusting circuit 4, where the vertical synchronizing signal of one of the said two signals is taken for a reference and timing of the vertical synchronizing signal of the other one is adjusted to come to identical. So the standard television signals whose timings are synchronized are obtained in the output of the circuit 4. Then, these two signals A and B are respectively supplied to a time-base compression circuit A5 and that B5, where respectively time-base compressed in the unit of one-field period. And thus signals whose time bases are compressed to a half are obtained. The signals are mixed by a mixer 7, and a resulting synthesized signal (f) is supplied to a recording-system circuit 9 through a mode switching switch 8, and recorded on a recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a recording and reproducing apparatus for television signals, and particularly to a recording and reproducing apparatus for selectively recording and reproducing a high-definition television signal and a plurality of standard television signals. It provides equipment.

Conventional technology Conventional television systems include NTSC system and PA
There are standard television systems such as L system (hereinafter abbreviated as standard system). In recent years, a high-definition television system (hereinafter referred to as "high-definition system") has been devised in order to obtain higher image quality than the standard system.

3. Problems to be solved by the invention Although this high-definition television system is a future system,
It is not a method that completely replaces the conventional standard method, but it is thought that it will coexist with the standard method during its dissemination process.

Therefore, it is desirable that the recording and reproducing apparatus be capable of selectively recording and reproducing both of these types.

In order to record and reproduce this high-definition television signal, a recording and reproduction system that can record and reproduce a wider band signal than conventional standard television signals is required. Therefore, by using such a recording and reproducing device, it is possible to record and reproduce a plurality of conventional standard television signals.

Means for solving the problem There is a first recording and reproducing mode in which a plurality of standard television signals are recorded and reproduced, and a second recording and reproducing mode in which a high-definition television signal with a wider band than the standard television signal is recorded and reproduced. A timing adjustment means for adjusting the timings of the plurality of standard television signals so that the synchronization signal timings of the plurality of standard television signals are synchronized with each other, and a time axis compression of the plurality of standard television signals outputted from the adjustment means. ,
Furthermore, a combining means for time-division multiplexing to obtain a composite signal, and switching between the composite signal and the high-definition television signal according to the mode, and transmitting the composite signal in the first mode and the high-definition television signal in the second mode. means for recording and reproducing signals from the switching means on a recording medium;
Separation means for obtaining a plurality of time-axis compressed standard television signals from the composite signal during reproduction in a first mode; and a separation means for time-axis expanding the signal from the separation means to generate a plurality of reproduction standard television signals. The present invention realizes a recording and reproducing apparatus that selectively records and reproduces a plurality of standard television signals and high-definition television signals.

Operation The recording and reproducing apparatus of the present invention has a first recording and reproducing mode in which a plurality of standard television signals are recorded and reproduced, and a second recording and reproducing mode in which a high quality television signal is recorded and reproduced.

The five-vane timing adjustment means adjusts the timing of the standard television signals so that the synchronization signal timings of the plurality of standard television signals are synchronized with each other, and performs time axis compression and time division multiplexing in the combining means. make it easier.

The combining means individually time-base compresses the plurality of standard television signals from the adjusting means and further time-division multiplexes them to obtain one composite signal. As a result, this composite signal is a signal in which multiple television signals are combined into one signal. The band of this composite signal is made wider by time axis compression, and is almost equivalent to the band of a high-definition television signal.

The switching means switches between the composite signal and the high-definition television signal in accordance with the mode, and outputs the composite signal in the first mode and the high-definition television signal in the second mode. Then, the signal from the switching means is recorded on the recording medium by the recording/reproducing means. In other words, multiple standard television signals are converted into a composite signal and recorded, and the recording and reproducing means can be recorded and reproduced without any changes. .

During reproduction, a composite signal is reproduced in the first mode, and a high-definition television signal is reproduced in the second mode.
In this mode, the reproduced high-definition television signal is output as is. In the first mode, a plurality of time-axis compressed standard television signals are separated from the reproduced composite signal by the separating means, and further time-axis expanded by the time-axis expanding means to reproduce a reproduced standard television signal.

Example FIG. 1 shows a block diagram of an embodiment of the present invention.

In FIG. 1, 1 is a high-definition television signal input terminal for inputting a high-definition television signal, 2.3 is a standard television signal input terminal for inputting a standard television signal, 4 is a standard television input terminal 2, Timing adjustment circuit 5 and 6 adjust the timing of the two standard television signals from timing adjustment circuit 4 to obtain a standard television signal in which the timings of their synchronization signals are synchronized; A time axis compression circuit that performs axis compression and obtains a time axis compressed signal, 7 is a time axis compression circuit 6
．． 6 is a mixer that mixes the two time-base compressed signals from 6 to obtain a composite signal; 8 is a mode changeover switch that switches between the composite signal and the high-definition television signal according to the two recording/reproducing modes; 9 is a changeover switch a recording system circuit that obtains a recording signal by converting the signal from 8 into a signal suitable for recording and reproduction;
is a recording head that records this recording signal on a recording medium, 1
Reference numeral 1 denotes a playback head that reproduces a signal recorded on a recording medium to obtain a playback signal, and 12 performs signal processing on this playback signal in the opposite manner to that of the recording circuit to obtain a playback high-definition television signal or a playback composite signal. Reproduction system circuit, 13 is a mode changeover switch for switching output light according to two recording and reproduction modes, 14
15.16 is a separation circuit for separating the reproduced composite signal into two reproduction time compressed signals; 15.16 is a time axis expansion circuit for time axis expansion of the reproduced time axis compressed signal from the separation circuit 14 to obtain a reproduced standard television signal; 17; 18.1 is a high-definition television signal output terminal that outputs a reproduced high-definition television signal.
9 is a standard television signal output terminal for outputting a reproduced standard television signal.

Next, the operation will be explained. First, a high definition television signal is input to the high definition television input terminal, and two standard television signals are input to the standard television input terminal 2.3. In this embodiment, the standard television signal is an NTSC signal, and the high-definition television signal is a signal whose required band is about twice that of the standard television signal. The required bandwidth for a normal high-definition television signal is approximately six times that of the NTSC system, but in consideration of satellite broadcasting, the band can be compressed to produce a high-definition television signal with a bandwidth approximately twice that of the NTSC system. be. For details, see Ninomiya, Otsuka, Izumi: High Definition Television Satellite Single Channel Transmission System (MUSE), Television Science and Technology Report, TEB
395-2, PP0E 5l-2 (1984), so the description thereof will be omitted.

Next, this high-definition television signal is applied to the recording system circuit 9 via the mode changeover switch 8 in the second mode. The recording system circuit 9 performs signal processing (for example,
FM modulation) to obtain a recording signal, which is recorded on a recording medium by a recording head 1o.

On the other hand, the two standard television signals are given to a timing adjustment circuit 4, so that the timing of the vertical synchronization signal of the other standard television signal is the same based on the vertical synchronization signal of one standard television signal. adjusted,
At its output, two standard television signals synchronized in timing are obtained. FIG. 2 is a time chart showing the timing of the signals in each part of FIG. It is divided.

As shown in the figure, the timings of these signals are shifted by time T, but the timing adjustment circuit 4 adjusts the timing of standard television signal B (in this example, time T
(delayed by 10 minutes), and a timing-synchronized signal similar to C is obtained. Next, these timing-synchronized standard television signals A and B are respectively sent to a time axis compression circuit A5. The signal is applied to the time axis compression circuit B6, where the time axis is compressed every field period, and a signal whose time is compressed to about 1/2 as shown in FIGS. 2d and 2a is obtained. Then, the signals are mixed in a mixer 7 to obtain a composite signal like f.

In the first mode, this composite signal is applied to the recording system circuit 9 via the mode changeover switch, and is recorded on the recording medium in the same manner as in the case of recording high-definition television.

During playback, the playback head 11 plays back the signal recorded on the recording medium, and the playback circuit 12 performs signal processing (for example, FM demodulation) that is the opposite of the signal processing in the recording circuit 9, resulting in high quality playback. A television signal or a regenerated composite signal is obtained. In the second mode, the reproduced high-definition television signal is outputted to the high-definition television output terminal via the mode changeover switch 13. In the first mode, the regenerated composite signal is applied to the separation circuit 14 via the mode changeover switch 1311. Next, the separation circuit 14
Then, the signal is separated into two time axis compressed signals and applied to the time axis expansion circuit A159 and the time axis expansion circuit B16, respectively. Then, these time axis expansion circuits 15 and 16 individually expand the time axis to obtain two reproduction standard television signals,
It is output to standard television signal output terminals 18 and 19.

The above is an explanation of one embodiment of the present invention, and a magnetic tape is used as a recording medium and a recording/reproducing means. State diagrams of the upper recording track are shown in FIGS. 3 and 4. Note that FIG. 3 shows a case in which a high-definition television signal is recorded, and FIG. 4 shows a case in which two standard television signals are recorded. As shown in the example in Figure 4, the recording areas of the two standard television signals are different, so if one of the signals is rewritten, the on signal becomes two signals, but the required bandwidth for high-definition television is (In this example, this is equivalent to two signals in the required band of standard television signals.) It is similarly possible to record and reproduce even more standard television signals.

Effects of the Invention According to the present invention, in a device for recording and reproducing high-definition television signals, it is possible to record and reproduce a plurality of standard television signals without changing the recording and reproducing means, and the effects are significant. .

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a block diagram of an embodiment of the present invention.
A time chart showing the timing relationship of the various signals in the figure,
3 and 4 are front views showing recording track states on the magnetic tape realized by the embodiment of FIG. 1. FIG. 1...High-definition television signal input terminal, 2゜3...Standard television signal input terminal, 4...
...timing adjustment circuit, 5. e...--Time axis compression circuit, 7...Mixer, 8...Mode changeover switch, 14...Separation circuit, '15
．． 16... Time axis expansion circuit. 13 Name of Behn's agent: Patent attorney Toshio Nakao, 1 person, Healfield Kokusha 1→

Claims (1)

[Claims] A recording and reproducing apparatus having a first recording and reproducing mode for recording and reproducing a plurality of standard television signals and a second recording and reproducing mode for recording and reproducing a high-definition television signal with a wider band than the standard television signals, the recording and reproducing apparatus comprising: a timing adjustment means for adjusting the timing so that the synchronization signal timings of a plurality of standard television signals are synchronized with each other in the recording/reproducing mode of 1; A time-base compression means for compressing, a combining means for time-division multiplexing a plurality of time-base compressed standard television signals from the time-base compression means to obtain one composite signal, and a composite signal and a high-definition television signal. The signal is switched according to the above mode, and the first
switching means for obtaining a composite signal in the first mode and a high-definition television signal in the second mode; recording and reproducing means for recording and reproducing the signals from the switching means; A television signal comprising a separation means for obtaining time-axis compressed standard television, and a time-axis expansion means for time-axis expansion of the signal from the separation means to obtain a plurality of reproduced standard television signals. Recording and playback device.