JP2654398B2 - Video signal recording device and playback device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for recording / reproducing a video signal or the like on / from a recording medium, and more particularly to a high-definition video signal compressed in a band and a current broadcast system (NTSC) video signal. And a magnetic recording / reproducing apparatus capable of recording and reproducing both.

[Conventional technology]

Conventionally, record and reproduce high-definition video signals with band compression
As VTR, for example, National Technical Report. Vol. 32. Number 4 (August 1986) pp. 2 to 10 (National Technical Report vol.32 No.4
(Aug. 1986) pp2-10).

However, no consideration is given to a system that records and reproduces both a band-compressed high-definition video signal and a current broadcast (NTSC) video signal.

By the way, the definition of HDTV (High Definition), which has twice as many scanning lines as the current broadcasting system (NTSC) and has dramatically improved image quality, is being promoted by improving the broadcasting system.
ition TV) broadcast is about to begin.

In the HDTV system, the video signal band is extremely wide as shown in FIG. For this reason, as shown in FIG. 3, a band compression method for compressing the band of a wide-band high-definition video signal and efficiently transmitting the band has been proposed.

Therefore, it is expected that in the future broadcasting form, HDTV broadcasting using band compression technology will coexist in addition to the current broadcasting (NTSC).

[Problems to be solved by the invention]

The above-mentioned prior art supports a band-compressed high-definition video signal, but does not consider a current broadcast system (NTSC) video signal.

For this reason, the user needs to prepare a separate magnetic recording / reproducing device for recording / reproducing the video signal of each system, and there is a problem that great inconvenience occurs in terms of usability and economy.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic recording and reproducing apparatus capable of recording and reproducing both band-compressed high-definition video signals and current broadcast system (NTSC) video signals with good consistency.

[Means for solving the problem]

The above object is achieved by employing the following configuration.

Any one of a high-definition video signal and a standard video signal having different bands and incompatible with each other is recorded on a plurality of parallel diagonal tracks on a magnetic tape by a rotating magnetic head mounted on a cylinder. In the recording apparatus, selecting means for selecting one of a first mode for recording a high-definition video signal and a second mode for recording a standard video signal; N (N) is set to be substantially the same as the signal band per channel of the video signal.
Means for time-expanding and dividing into video signals of two or more channels) to generate a first recorded video signal of N channels, and a second recorded video signal of one channel from an input standard video signal Means for performing, when the first mode is selected, the first recording video signal is recorded on a track on the magnetic tape by the rotating magnetic head in N channels, and the second mode is selected. Recording means for recording the second recording video signal on a track on the magnetic tape by the rotary magnetic head in one channel, and in the first mode and the second mode, the rotary magnetic head is substantially A video signal recording device comprising: control means for controlling the number of rotations to be the same.

[Action]

As the input video signal, either a band-compressed high-definition video signal or a current broadcast system (NTSC) video signal having a different signal band from each other is input.

By switching the signal processing circuit according to the identification signal for distinguishing the input video signal, according to a predetermined format,
The band-compressed high-definition video signal and the current broadcasting system (NT
SC) The signal processing is performed so that the signal band when recording on the magnetic tape is substantially the same as the video signal.

Further, both video signals can be recorded by setting the servo control to a predetermined recording mode according to the identification signal of the input video signal.

On the other hand, at the time of reproduction, the reproduction mode is identified based on a difference in the frequency of the control signal or a difference in the format of the recorded video signal, and an identification signal is output.

Then, the servo control is set to a predetermined reproduction mode in accordance with the above-mentioned reproduction mode identification signal, and the signal processing circuit is switched to process the reproduction signal according to a predetermined format, thereby restoring the original video signal. .

In this manner, the same device can record and reproduce both the band-compressed high definition video signal and the current broadcast system (NTSC) video signal.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 shows the current broadcasting system (NT
SC) A magnetic recording and reproducing apparatus according to an embodiment of the present invention capable of recording and reproducing both a video signal (hereinafter, referred to as an NTSC signal) and a band-compressed high-definition video signal (hereinafter, referred to as a band-compressed HDTV signal). It is a block diagram.

First, as an example, home VTRs that are now widely used
A case will be described in which an NTSC signal is recorded and reproduced in the same system (for example, the VHS system).

In FIG. 1, an NTSC signal input from an NTSC signal input terminal 1 at the time of recording includes a low-pass filter (hereinafter, referred to as LPF) 10 and a band-pass filter (hereinafter, referred to as BPF) 20.
Supplied to

In the LPF 10, a luminance signal is extracted from the NTSC signal and supplied to the FM modulation circuit 60 via the switching switch 50. The luminance signal is FM-modulated by the FM modulation circuit 60 and then supplied to one input terminal of the addition circuit 40.

In the BPF 20, a carrier color signal is extracted from the NTSC signal and supplied to the frequency conversion circuit 30.

The carrier chrominance signal near 3.58 MHz supplied to the frequency conversion circuit 30 is converted to a predetermined low frequency, for example, 629 KHz (hereinafter, referred to as 629 KHz).
After this signal is referred to as a low-frequency conversion color signal), the addition circuit
It is supplied to the other input terminal of 40.

The addition circuit 40 adds the luminance signal obtained as described above and the low-frequency conversion color signal, and outputs the added signal via the switching switch 51, the recording amplifier 70, and the switching switch 52 to the magnetic heads 90 and 90 '. Is recorded on the magnetic tape 100.

Note that the magnetic heads 90 and 90 '
The magnetic tape 100 is wound around the cylinder 101 by 180 ° or more.

By the way, the switching switches 50 to 52 are controlled in the following manner. That is, the recording mode switching switch 3 selects either the NTSC signal or the band-compressed HDTV signal, and the identification signal generation circuit 4 responds to the selection.
And outputs the V _R.

Switching switch 50 to 52 by the identification signal V _R, NTSC
Connected to terminal N when recording signals, and connected to terminal H when recording band-compressed HDTV signals, and switched so that predetermined signal processing is performed on each of NTSC signals and band-compressed HDTV signals. Can be

Further, the identification signal V _R is also supplied to the servo control circuit 80, capstan motor control, with cylinder motor control is performed, control signal recording and reproducing head for servo control during reproduction (hereinafter, CTL head Written as) 8
A control signal (hereinafter, referred to as a CTL signal) recorded on the magnetic tape 100 through 3 is output from the servo control circuit 80.

If you do the above, you can see that the widely used home VT
An NTSC signal can be recorded on the magnetic tape 100 in the same manner as R (for example, the VHS method). Next, a case where the NTSC signal is reproduced will be described.

The video signal recorded on the magnetic tape 100 is a magnetic head 9
0, 90 'and supplied to the preamplifier 210 via the switching switch 200.

The output signal from the preamplifier 210 is supplied to the BPF 220 and the LPF 230, and the BPF 220 outputs the FM-modulated luminance signal to the LPF 230.
Then, a low-frequency conversion color signal is extracted.

Among them, the luminance signal is FM through the switch 201.
After being supplied to the demodulation circuit 260 and modulated into the original baseband signal, it is input to one input terminal of the addition circuit 250 via the switching switch 202.

On the other hand, the low-frequency conversion color signal is supplied to the frequency conversion circuit 240, frequency-converted to the original carrier color signal near 3.58 MHz, and then input to the other input terminal of the addition circuit 250.

The addition circuit 250 combines the luminance signal and the carrier chrominance signal obtained as described above, and outputs the original NTSC signal from the terminal 5.

By the way, the switching switches 200 to 202 are controlled as follows. That is, during playback, the CTL head 83
In accordance with the identification signal V _P output from the reproduction mode identification circuit 82 based on the reproduction CTL signal reproduced, the switching switch 200 to 202 in the case of the NTSC signal is connected to the terminal N side,
In the case of a band-compressed HDTV signal, the terminal H is connected to
Switching is performed so that predetermined signal processing is performed on each of the SC signal and the band-compressed HDTV signal.

At the time of reproduction, the servo control operation is set to one of the mode for reproducing the NTSC signal and the mode for reproducing the band-compressed HDTV signal, and the C reproduced from the CTL head 83 is set.
The playback mode identification circuit 82 is operated by the TL signal to perform playback.
Identifying a frequency of the CTL signal to obtain an identification signal V _P, capstan motor in response to the identification signal V _P in the servo control circuit 80, by controlling so that the rotational speed of the cylinder motor becomes a predetermined value, A good and automatic reproduction video signal can be obtained.

If you do the above, you can see that the widely used home VT
NTSC signals can be recorded and reproduced using the same method as R (for example, VHS method).

More specifically, a high-quality home-use VTR system (for example, S-VHS system) that is now widely spread, that is, 62 mmφ
The rotation of the cylinder is controlled to 1800 rpm, and FM
The carrier center frequency of the signal is 6.2 MHz and the maximum frequency shift is
When set to 1.6 MHz, NTSC signals with a bandwidth of about 4 MHz can be recorded and reproduced with almost no image quality deterioration.

Next, a case in which a band-compressed HDTV signal is recorded and reproduced will be described.

Hereinafter, the magnetic recording / reproducing apparatus of the present invention shown in FIG. 1 will be described by taking as an example a band-compressed HDTV signal having a signal band approximately twice (8.1 MHz) the NTSC signal.

In FIG. 1, the band-compressed HDTV signal input from the band-compressed HDTV signal input terminal 2 during recording is supplied to a recording signal processing circuit 200.

The recording signal processing circuit 200 is approximately twice the NTSC signal (8.1 MHz).
z) The above band-compressed HDTV signal having the signal band of (2) is divided into two channels, and the recording signal band per channel is made almost the same as the band of the NTSC signal, and the signal is processed so that recording can be performed on the magnetic tape 100. FIG. 4 shows a specific example, and FIG. 5 shows a waveform showing a process of generating the recording signal.

The operation of the recording signal processing circuit 200 will be described below with reference to FIGS.

In FIG. 4, a band-compressed HDTV signal (FIG. 5 (a)) input from an input terminal 201 is supplied to a clock generation circuit 203.
The analog signal is sequentially converted into a digital signal by the A / D converter 202 by the sampling clock WCK generated in the step (1), and then supplied to the time-axis expansion 2-channel dividing circuit 204.

The time axis expansion 2 channel division circuit 204 is mainly composed of a memory, and the digital signal from the A / D converter 202 is written to the memory of the time axis expansion 2 channel division circuit 204 based on the sampling clock WCK. Be included.
In the time axis expansion 2 channel dividing circuit 204, the band compression HDT
The V signal (FIG. 5 (a)) is sequentially distributed to two channels in units of one horizontal scanning line, and the time axis is extended.

The time base extension, for the frequency f _W in the sampling black poke WCK, f _R is _{f W = n × f R (} n> 1) ...... (1) becomes a relationship read clock RCK to the clock generation circuit This is accomplished by reading the digital signal generated at 203 and written to the memory with this read clock RCK.

At this time, the signal S ₁ ′ S ₂ ′ of each channel output from the time-axis expansion two-channel dividing circuit 204 is 1
The time axis is extended n times in units of horizontal scanning lines, and the signals S ₁ ′ and S ₂ ′ of each channel are selected by selection circuits 206 and 207, respectively.
Supplied to

On the other hand, in the synchronization generation circuit 205, the read clock RCK
, New horizontal synchronization information SY is generated and supplied to the selection circuits 206 and 207.

In the selection circuit 206, the signal S ₁ ′ and the horizontal synchronization information SY
And time-division multiplexed by appropriately selecting the door, give recording signals S ₁ shown in FIG. 5 (b), is converted into an analog signal by the D / A converter 208 is outputted from an output terminal 210. Similarly, to obtain a recording signal S ₂ shown in FIG. 5 (c) by the selection circuit 207, is converted into an analog signal by a D / A converter 209,
Output from the output terminal 211.

In the specific example shown in FIG. 5, the expansion rate n in the equation (1) and the period τ _S of the horizontal synchronization information SY are 2H = τ _S + n when one horizontal scanning period of the band-compressed HDTV signal is 1H. × H (2) As an example, when n = 1.8, τ _S = 0.2H, the recording signals S ₁ , S ₂ are respectively band-compressed HDT
This means that the time axis of the V signal is expanded 1.8 times in units of horizontal scanning.

Therefore, the signal band B of the recording signals S ₁ and S ₂ is B = 8.1 MHz / n = 8.1 MHz / 1.8 = 4.5 MHz (3), which can be made almost the same as the band of the NTSC signal. .

Note that various types of the horizontal synchronization information SY output from the synchronization generation circuit 205 can be considered, and FIG. 6 shows an example thereof.

FIG. 6 (a) shows the negative sync information, FIG. 6 (b) shows the positive sync information added to the negative sync information to improve the S / N of the sync information, and FIG. 6 (c) shows the S / N of the sync information. In order to further improve N, a burst signal is added to the negative synchronization information.

In particular, the synchronization information shown in FIG. 11C is optimal for correcting a time-base error such as jitter or skew during reproduction by minimizing the influence of noise.

As is clear from the above description, the recording signal processing circuit 200 shown in FIG.
The signal is converted to the recording signal bandwidth per channel 4.
This is reduced to 5 MHz, and the recording signal band becomes almost the same as the NTSC signal.

For this reason, the recording signals S ₁ and S ₂ output from the recording signal processing circuit 200 are FM-modulated by the same FM allocation as in the case of recording the NTSC signal, respectively, and by the same mechanical system,
Recording can be performed at almost the same recording wavelength.

Accordance connexion, in Figure 1, the recording signal S ₁ output from the recording signal processing circuit 200, the switching switch 50, FM modulation circuit 60, the switching switch 51, recording amplifier 70, via the switching switch 52, the magnetic head The data can be recorded on the magnetic tape 100 at 91 and 91 '.

The FM modulation circuit 60 and the recording amplifier 70 may be exactly the same as those used for recording the NTSC signal.
Since they can be shared by the switching operations of 50 and 51, the circuit scale can be reduced.

Incidentally, the switching switch 50, 51 and 52, by the identification signal V _R, as described above, the switching switch 50, 51, 52 in the case of recording the bandwidth compression HDTV signal is connected to the terminal H side, the predetermined Switching is performed so that signal processing is performed.

On the other hand, the recording signal of the other channel output from the recording signal processing circuit 200 is a newly provided FM modulation circuit 6.
1. The data is recorded on the magnetic tape 100 by the magnetic heads 92 and 92 'via the recording amplifier 71.

The FM modulation circuit 61 and the recording amplifier 71 are
The modulation circuit 60 and the recording amplifier 70 may be exactly the same.

Note that two sets of magnetic heads (91
And 91 ', 92 and 92') are mounted on the cylinder 101 for recording and reproducing band-compressed HDTV signals.

In this embodiment, the servo control when recording the band-compressed HDTV signal is performed by controlling the rotation speed of the cylinder because the band of the recording signals S ₁ and S ₂ of each of the above-described channels is reduced to about the same as the band of the NTSC signal. May be controlled to the same rotation speed (for example, 1800 rpm) as when recording the NTSC signal.

Further, in accordance with the tape running speed in the identification signal V _R, is controlled to be twice the NTSC signal in the servo control circuit 80, a band compression HDTV signal can be recorded and reproduced at almost the same S / N and NTSC signals This produces the effect.

Next, a case where the band-compressed HDTV signal is reproduced will be described.

The recording signal S ₁ recorded on the magnetic tape 100 is reproduced by the magnetic heads 91 and 91 ′ and supplied to the preamplifier 210 via the switching switch 200.

The output signal from the preamplifier 210 is supplied to the FM demodulation circuit 260 via the switching switch 201, and the FM demodulated reproduction signal is input to one input terminal of the reproduction processing circuit 300 via the switching switch 202.

The switching switch 200 to 202, as described above, in response to the identification signal V _P output from the reproduction mode identification circuit 82, when the bandwidth compression HDTV signal is connected to the terminal H side,
Switching is performed so that the predetermined signal processing is performed.

The preamplifier 210 and the FM demodulation circuit 260 are the same as those used when reproducing the NTSC signal, and can be shared by the switching operations of the switching switches 200 to 202, so that the circuit scale can be reduced.

On the other hand, the recording signal S ₂ of the other channel recorded on the magnetic tape 100 is reproduced by the magnetic heads 92 and 92 ′, and the reproduced signal is transmitted through a newly provided preamplifier 211 and FM demodulation circuit 261. The signal is input to the other input terminal of the processing circuit 300.

The reproduction signal processing circuit 300 compresses the reproduction signal on the time axis and performs channel synthesis to restore the original band-compressed HDTV signal. One specific example is shown in FIG.

In Figure 7, the reproduction signal S ₁ inputted from the input terminal 301 is supplied to a sync separator 303, A / D converter 305.
In the sync separation circuit 303, the horizontal sync information S added at the time of recording is
Separate Y. The clock generation circuit 307 generates a clock WCK 'phase-synchronized with the separated horizontal synchronization information SY.

On the other hand, the reproduction signal S ₁ supplied to the A / D converter 305 is
The analog signals are sequentially converted into digital signals based on the clock WCK '.

Clock WCK 'is for is generated from the reproduced signals S _1, in the A / D converter 305, can be completely in phase synchronous sampling in the time axis error such Jitsuta the reproduction signals S ₁ has.

The reproduced signals S ₁ that has been converted into a digital signal, time base corrector (hereinafter referred to as TBC) is 309 in the time axis error correction. That is, the TBC309 is composed of a memory, writing to the memory is performed by the clock WCK 'which follows the time base error of the reproduced signal S _1, read from the memory the reference clock generated based on such as a crystal oscillator circuit
By the frequency output from 311 is performed in a stable reference clock RCK1, can be corrected time base error included in the above reproduced signal S _1.

However, the frequency f _W ′ of the clock WCK ′ and the clock RCK1
f _R1 is the frequency of the read clock RCK shown in Fig. 4.
f Same as _R.

The reproduction signal S ₁ output from the TBC 309 with the time axis error corrected is supplied to the time axis compression channel synthesis circuit 312.

The reproduction signal S ₂ of the other channel which is input from the input terminal 302, sync separator 304, A / D converter 306, the clock generation circuit 308, TBC310, is exactly like the signal processing and the reproduction signals S ₁ The time axis error is corrected and supplied to the time axis compression channel synthesis circuit 312.

In the time axis compression channel synthesizing circuit 312, signal processing reverse to that of the time axis expansion channel dividing circuit 204 in FIG. 4 is performed to convert the signal into the original band compressed HDTV signal. That is, the horizontal synchronizing information SY added at the time of recording is removed, time axis compressed, and channel synthesis is performed.

The time axis compression channel synthesizing circuit 312 is mainly composed of a memory, and the time axis compression converts the reproduction signals S ₁ and S ₂ output from the TBCs 309 and 310 in which the time axis error is corrected to the frequency f _R1. The reference clock RCK1 is written into the memory of the time axis compression channel synthesizing circuit 312, and the frequency f _R2 is related to the frequency f _R1 of the reference clock RCK1 by the following relationship: f _R2 = n × f _R1 (4) And the time axis is compressed to 1 / n.

Note that the reference clock RCK2 is generated by the reference clock generating circuit 311, the frequency f _R2 is a stable clock.

Therefore, as described above, for example, at the time of recording, n = 1.8, the band-compressed HDTV signal is expanded by 1.8 times in the time axis, and
When recording is performed by dividing the channel, during reproduction, the original band-compressed HDTV signal can be restored by compressing the time axis by 1 / 1.8 and combining the channels by the time-axis compression channel combining circuit 312.

The restored band-compressed HDTV signal output from the time-axis compression channel synthesizing circuit 312 is sequentially converted from a digital signal to an analog signal by the D / A converter 313, and the output terminal 31
4 is supplied to the band compression HDTV signal output terminal 6 shown in FIG.

1 generates a vertical synchronizing signal VD and a horizontal synchronizing signal HD in connection with the reproduction signal processing performed by the reproduction signal processing circuit 300, and outputs the output terminals 7 and 8 respectively. Output from

Also, during reproduction, in response to the identification signal V _P output from the reproduction mode identification circuit 82, the servo control circuit 80, the same rotational speed as the rotational speeds of the cylinder for recording and reproducing an NTSC signal (for example, 1800 rpm) And the tape running speed is N
If servo control is performed twice as much as when recording and reproducing TSC signals, S / N is almost the same as when recording and reproducing NTSC signals.
Thus, a band-compressed HDTV signal can be obtained well and automatically.

Therefore, as described above, if the signal processing circuit and the magnetic head are switched in accordance with the input video signal so that predetermined signal processing can be performed, the signal bands can be mutually changed without changing the rotation speed of the cylinder. Alternating NTSC signal and band compression HDTV
Signals can be recorded / reproduced with the same FM allocation and mechanism system and with almost the same S / N.

Furthermore, since the recording and reproducing method of the NTSC signal is the same as the method of the currently popular home VTR, the band-compressed HDTV signal can be recorded and reproduced while maintaining complete compatibility with the current home VTR.

Next, a specific example of the reproduction mode identification circuit 82 in FIG. 1 is shown in FIG. 8 and will be described with reference to the waveform diagram of FIG.

In FIG. 8, a CTL signal input from an input terminal 400 drives a monostable multivibrator 402 via a preamplifier 401.

The CTL signal is recorded on the magnetic tape 1
For example, when the NTSC signal is reproduced in the mode in which the NTSC signal is recorded, when the NTSC signal is recorded, the CTL signal shown in FIG. 9A is obtained, whereas the band-compressed HDTV signal is recorded. In this case, since the tape is recorded at twice the tape speed, as shown in FIG.
The CTL signal is reproduced.

Therefore, the monostable multivibrator 402 is driven by the reproduced CTL signal to record the NTSC signal, and to record the signal of FIG. 9B when the band-compressed HDTV signal is recorded. A signal is generated, integrated by an integration circuit 403, and a level is determined by a determination circuit 404 having a predetermined threshold value for the input signal, whereby an identification signal _VP is generated and output from an output terminal 405.

In FIG. 1, the identification of the recording signal is performed by switching from the outside. This is because of the difference in the system of the NTSC signal and the band-compressed HDTV signal, specifically, the difference of the synchronization format or one horizontal scanning. There may be a method for automatic identification based on the difference in the period.

In this way, the NTSC signal can be recorded and reproduced with compatibility with the currently popular home VTR, and the band-compressed HDTV signal having a wider band than the NTSC signal can be recorded and reproduced with good consistency. An easy-to-use magnetic recording / reproducing apparatus can be realized by the automatic determination of the reproduced signal.

〔The invention's effect〕

As described above, according to the present invention, the NTSC signal can be recorded and reproduced while maintaining compatibility with the currently popular home VTR, and the band-compressed HDTV signal can be recorded and reproduced by one magnetic recording and reproducing apparatus. Therefore, the usability for the user is improved, and a magnetic recording / reproducing apparatus with good economy can be realized.
A magnetic recording / reproducing apparatus having excellent functions can be provided, excluding the above-described problems of the related art.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram for explaining a high-definition television system, FIG. 3 is a diagram for explaining a conventionally proposed band-compressed high-definition video signal, and FIG. 5 is a block diagram showing a specific example of the recording signal processing circuit 200 in FIG. 1, FIG. 5 is a waveform diagram for explaining the operation of the embodiment of FIG. 4, and FIG. 6 is a synchronization generation circuit 205 in FIG. 7 is a waveform diagram showing an example of the synchronization information generated in FIG. 7, FIG. 7 is a block diagram showing a specific example of the reproduction signal processing circuit 300 in FIG. 1, and FIG. 8 is a specific example of the reproduction mode identification circuit 82 in FIG. FIG. 9 is a block diagram showing an example, and FIG. 9 is a waveform diagram for explaining the operation of FIG. 1, 2 input terminals, 5 to 8 output terminals, 3 recording mode switching switches, 4 identification signal generation circuits, 50 to 5
2,200-202 switching switch, 80 servo control circuit, 200 recording signal processing circuit, 83 CTL head, 82
... Reproduction mode identification circuit, 300 ... Reproduction signal processing circuit.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kyoichi Hosokawa 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Home Appliances Research Laboratory, Hitachi, Ltd. (72) Inventor Manabu Katsuki 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Inside Hitachi, Ltd. Home Appliance Research Laboratory (72) Inventor Kazutaka Naka 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Hitachi, Ltd. Home Appliance Research Laboratory Co., Ltd. (56) References JP-A-60-241390 (JP, A) JP-A-60 JP-A-191588 (JP, A) JP-A-63-269877 (JP, A) JP-A-2-73790 (JP, A)

Claims (5)

(57) [Claims] An incompatible high-definition video signal and a standard video signal having different bands are recorded on a plurality of parallel oblique tracks on a magnetic tape by a rotating magnetic head mounted on a cylinder. A recording device configured as above, comprising: a selection unit that selects one of a first mode for recording a high-definition video signal and a second mode for recording a standard video signal; The signal is time-expanded and divided into N (N is an integer of 2 or more) channel video signals so as to be substantially the same as the signal bandwidth per channel of the standard video signal, and the N channel first recorded video signal Means for generating a second recording video signal of one channel from an input standard video signal; and, when the first mode is selected, the first recording video signal When the second mode is selected, the second recording video signal is recorded on the track on the magnetic tape by one channel on the track on the magnetic tape. Recording means for controlling the rotating magnetic head to have substantially the same number of revolutions in the first mode and the second mode. apparatus. 2. The video signal recording apparatus according to claim 1, wherein the control means sets the tape running speed in the first mode to a value exceeding the tape running speed in the second mode. Characteristic video signal recording device. 3. The video signal recording apparatus according to claim 1, wherein said recording means records in said first mode by two sets of rotating magnetic heads each facing said cylinder at 180 degrees. In a second mode, recording is performed by a set of rotary magnetic heads that face the cylinder at 180 degrees, respectively. 4. The video signal recording apparatus according to claim 1, wherein the selection unit identifies which video signal system is used from the input video signal, and determines whether the selected mode is the first mode. A video signal recording apparatus for automatically selecting whether the mode is the second mode. 5. A video signal of N channels (N is an integer of 2 or more) is time-expanded, divided, converted into a first recording video signal of N channels, and recorded on a plurality of parallel oblique tracks on a magnetic tape. The converted high-definition video signal and a one-channel second recording video signal having substantially the same signal band as the first recording video signal, and substantially the same number of revolutions as when recording the high-definition video signal A reproducing apparatus configured to reproduce any one of standard video signals recorded on a plurality of parallel oblique tracks on a magnetic tape by a rotating magnetic head, wherein the standard video signal has a different band from the standard video signal and is compatible with the standard video signal. Identification means for identifying, based on a reproduction signal from a magnetic tape, whether the mode is a first mode for reproducing a high-definition video signal having no characteristic or a second mode for reproducing the standard video signal; If the recording mode is identified, the first recorded video signal recorded on the track on the magnetic tape is reproduced by the rotating magnetic head to obtain an N-channel first reproduced video signal, and the N-channel first reproduced video signal is obtained. First restoration means for time-compressing and synthesizing the first reproduced video signal to restore the original high-definition video signal of one channel; and, when the second mode is identified, a track on the magnetic tape. The second recorded video signal recorded is reproduced by the rotating magnetic head to obtain a second reproduced video signal of one channel, and a second standard video signal for restoring an original standard video signal from the second reproduced video signal is obtained. And a restoring means.