JPH0789402B2 - Video signal recorder - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal recording / reproducing apparatus such as a video tape recorder.

2. Description of the Related Art In recent years, a video tape recorder has been developed in the fields of business and broadcasting, in which a color video signal is separated into two channel component signals of a luminance signal and a color signal and recorded (for example, M format or βCAM. It is a VTR called, etc., Broadcasting Technical Magazine, October 1982 issue P872-P89
Recording method as described in 0).

Problems to be Solved by the Invention A conventional two-channel component VTR has a color signal track adjacent to a luminance signal track in a recording track recorded on a magnetic tape. Overwriting recording (so-called solid writing) is impossible even if an azimuth angle is provided between the head for signal recording and it is difficult to switch between so-called standard tape running mode and long-time tape running mode. Met.

Means for Solving the Problems The present invention solves the above-mentioned problems, and in a 2-channel component recording VTR, an image divided into two channels is provided so as to have two or more kinds of tape running speeds during recording. A device for recording each of the signals, comprising two sets of two video heads arranged on the rotating cylinder at positions displaced by 90 ° from each other and a tape drive system having two or more kinds of tape running speeds during recording. It was done.

Operation The present invention, with the above-described configuration, enables two-channel component recording and can be used by switching between the standard tape running mode and the long time tape running mode.

Example Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of an electromagnetic conversion system showing a configuration of a main part of the present invention. FIG. 1 is a circuit block diagram showing a signal processing unit of the present invention. FIG. 2 is a schematic diagram of the electromagnetic conversion system 14 showing the essential configuration of the present invention. A luminance signal as shown in FIG. 3A, for example, is input to the input terminal 1. Input terminal 2
For example, a time axis compression-multiplexed color signal as shown in FIG. 3B is input to. Here, as an example, a luminance signal and a time axis compression multiplexed color signal form a two-channel component signal. The luminance signal is connected to one input terminal of the first switcher 4 together with the horizontal synchronizing signal separation circuit (HSS) 3. In the HSS3, the horizontal synchronizing signal is separated and supplied to the flip-flop (FF) 5 as shown in FIG. 2C. The control terminal 6 of the first switcher 4 is supplied with the output signal of FF5 as shown in FIG. 3D. An example of the internal configuration of the first switcher 4 includes two switches 7 and 8 as shown in FIG.
It outputs to the output terminals 9 and 10. At the output terminal 9,
A signal as shown in FIG. 3E is obtained, and at the output terminal 10,
A signal as shown in FIG. 3F is obtained. The output signal from the output terminal 9 is modulated by the FM modulator 11 and supplied to the electromagnetic conversion system 14. The output signal from the output terminal 10 is delayed by the delay circuit 43 for a time corresponding to 1/2 field, and then the FM modulator 12
And is supplied to the electromagnetic conversion system 14. These input terminals 1,2, HSS3, first switcher 4, FF5, FM modulator 11,1
The delay circuit 43 and the delay circuit 43 form the recording circuit unit 13. FIG. 2 shows a schematic diagram of the essential parts of the electromagnetic conversion system 14. The FM signals input to the input terminals 15 and 16 of the electromagnetic conversion system 14 are rotary transformers 18, 19, 20, 21
Through the video head placed on the rotating disk 22
It is recorded on the magnetic tape 23 via A ₁ , A ₂ , B ₁ , and B ₂ .
The rotating disk 22 rotates in the direction of arrow 24 at a rotation speed of about 30 Hz (about 25 Hz depending on the broadcasting system). (The motor as a drive source and the motor control circuit are not shown.) The video heads A ₁ , A ₂ , B ₁ , B ₂ are mounted at positions 90 ° apart from each other.

The magnetic tape 23 is run in the direction of the arrow 29 by the capstan 25 and the pinch roller 26 via the guide posts 27 and 28. By selecting a recording mode switch (not shown), the running speed is standard tape running mode, which is the normal running speed, and long tape running, which is 1/3 (1/2 in some cases) of the normal running speed. The mode is switched to. FIG. 5 shows a recording track pattern (portion) recorded on the magnetic tape 23 in the standard tape running mode. Fifth
In the figure, an arrow 24 indicates the scanning direction of the video heads A ₁ , A ₂ , B ₁ , B ₂ , and an arrow 29 indicates the traveling direction of the magnetic tape 23.
Recording tracks 101 and 105 are recording tracks recorded by the video head A ₁ , recording tracks 102 and 106 are recording tracks recorded by the video head A ₂ , and recording tracks 103 are recording tracks recorded by the video head B ₁ . Yes, the recording track 104 is the recording track recorded by the video head B ₂ . The signals recorded by the video heads A ₁ and B ₁ are shown in FIG. 3E, and the signals recorded by the video heads A ₂ and B ₂ are shown in FIG. 3F.
And As described above, since the video heads A ₁ , A ₂ , B ₁ , and B ₂ are mounted at 90 ° intervals, the time corresponding to 90 °, that is, 1/2 field time, is shown in FIG. 3F. By delaying the signal with the delay circuit 43, a track pattern as shown in FIG. 5 is obtained. That is, the luminance signal (Y) is located adjacent to the luminance signal (Y), and the color signal (C) is located adjacent to the color signal (C). For this reason,
Even if overwriting recording (solid writing recording) is performed, the level of interference from adjacent tracks is small, and high-density recording without a guard band by overwriting recording (solid writing recording) becomes possible. Needless to say, as shown in FIG. 5, azimuth recording between tracks is an effective means for overwriting recording (solid writing recording).

Next, a case where recording is performed at a running speed of 1/3 (1/2 in some cases) of a normal running speed, that is, a case of a long time tape running mode will be described. Tape running speed is 1 /
3, so each video track has a portion of it
Re-recorded by the next scanning video head,
A tape pattern as shown in FIG. 6 is obtained. In addition,
In order to make the drawing easier to see, FIG. 6 shows the track width direction in a three-fold enlarged view as compared with FIG. Recording track 301,
Reference numeral 305 is a recording track recorded by the video head A ₁ , recording tracks 302 and 306 are recording tracks recorded by the video head A ₂ , and recording track 303
Is a recording track recorded by the video head B ₁ , and the recording track 304 is a recording track recorded by the video head B ₂ .

As in the conventional example (such as βCAM or M format), for example, the A ₁ head and the B ₁ head are mounted close to each other, and the rotation plane of the A ₁ head and the B ₁ head corresponds to one track pitch. 7 and the A ₂ and B ₂ heads are also mounted in the same manner, and the recording track pattern is as shown in FIG. 7 in the standard tape running mode. That is, the A ₁ and B ₁ heads are the luminance signals (Y)
The A ₂ and B ₂ heads are in charge of recording and reproducing of the color signal (C). As shown in FIG. 7, since the color signal is recorded adjacent to the luminance signal, overwriting recording (solid writing recording) becomes impossible due to interference between adjacent tracks, and a guard band is required. Therefore, the conventional example has a low recording density according to the embodiment of the present invention. It should be noted that in FIG. 6, recording tracks 201 to 206 are examples of conventional recording tracks.

Furthermore, in the long-time tape running mode, recording and reproduction cannot be performed because the video tracks overlap each other.

In the above description, the luminance signal and the time axis compression multiplexed color signal are used as the signals handled by the video signal recording device for recording each of the video signals divided into two channels. Even when the signal recorded in is the two-channel recording in which the FM-luminance signal and the FM-mixed two-color-difference signal are frequency-multiplexed, by switching the channel switcher provided in the recording circuit unit 13 every 1H,
Since the recording track patterns on the magnetic tape 23 as shown in FIGS. 5 and 6 are obtained, it is possible to realize a plurality of recording tape running modes together with overwriting (solid writing) as in the present embodiment.

That is, the present invention is applied to various video signal recording devices in which the electromagnetic conversion unit 14 is capable of 2-channel recording, and the input signal of the recording circuit unit 13 is a luminance signal and two types of color difference signals. However, it does not matter whether it is the R signal, the G signal, or the B signal, or the signal obtained by time-axis compression multiplexing of the luminance signal and the two kinds of color difference signals as shown in this embodiment. Further, even if a 1-channel signal in which a luminance signal and a line-sequential color signal are time-axis compression-multiplexed like a MAC signal is an input signal of the recording circuit unit 13, the electromagnetic conversion unit 14 performs 2-channel recording. In order to do so, it is similarly applied to the case of handling as a signal of two channels extended in the time axis. The same applies to a 1-channel signal in which the luminance signal and the two types of color difference signals are all time-axis compression multiplexed.

The recording track pattern on the magnetic tape 23 is not limited to the one shown in FIG. 5, and for example, the luminance signal and the color signal are switched every nH (n: any positive integer), and the luminance signal is changed. The luminance signals are recorded adjacent to the video signals, and the color signals are recorded adjacent to the color signals so that the video heads A ₁ , A ₂ ,
The same effect can be obtained by arranging B ₁ and B ₂ . Delay circuit 43
The same effect can be obtained even if the delay time is not limited to 1/2 field.

EFFECTS OF THE INVENTION In a recording apparatus in which two-channel recording is performed on a magnetic tape pattern, if each head for two-channel recording is mounted close to each other as in the conventional example, it is between the luminance signal track and the chrominance signal track. Since it is necessary to provide a guard band, the tape utilization rate deteriorates accordingly. Further, it is impossible to use a plurality of tape running speed modes such as a standard tape running mode and a long time running mode at the time of recording. However, as shown in the present invention, the two-channel recording heads are arranged at positions separated by 90 °, and the recording channel of the recording signal is switched for each nH, and the brightness is set on the adjacent track of the brightness signal on the magnetic tape pattern. By configuring the signals to be recorded and the color signals to be recorded on the adjacent tracks of the color signals, the influence of crosstalk between adjacent tracks can be reduced to a negligible level. Since there is no need to provide a guard band, there is an effect that the tape utilization rate increases accordingly.

Further, there is an effect that it is possible to have a plurality of recording tape running modes such as a standard tape running mode and a long time tape running mode.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing a signal processing unit in one embodiment of the present invention, FIG. 2 is a schematic configuration diagram of an electromagnetic conversion system 14 in FIG. 1, and FIG. 3 is a signal waveform diagram of each unit in FIG. FIG. 4 is a specific configuration diagram of the switcher 4 in FIG. 1, FIG. 5 is a pattern diagram showing an example of a recording pattern recorded on the magnetic tape 23 according to the present invention, and FIG. FIG. 7 is a pattern diagram showing another example of the pattern recorded on the tape 23, and FIG. 7 is a pattern diagram showing an example of the pattern recorded on the magnetic tape 23 in the conventional example. 3 ... Horizontal sync signal separation circuit, 4 ... First switcher, 5 ... Flip-flop, 14 ... Electromagnetic conversion system, 23
...... Magnetic tape, 43 ...... Delay circuit, 101,102,103,104,10
5,106 …… Recording tracks, 301,302,303,304,305,306 ……
Recording track, A ₁ , A ₂ , B ₁ , B ₂ ... Video head.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kazuhiro Yamanishi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-150225 (JP, A) JP-A-60- 70883 (JP, A) JP-A-54-78108 (JP, A)

Claims (1)

[Claims] 1. A device for recording each of the video signals divided into two channels, which are arranged on a rotary cylinder at 90 degrees each other.
2 sets of 2 video heads arranged at offset positions,
2 channels input, equipped with a tape drive system having two or more kinds of tape running speeds during recording, a channel switcher, a 1/2 field delay circuit, a first FM circuit, and a second FM circuit. Video signal of the channel switcher, the channel switcher switches the channels of the input video signal to each other every nH (n: positive integer, H: horizontal synchronization interval), and The output signal passes through the 1/2 field delay circuit to the first F
It supplies to the M circuit, the other output signal is supplied to the second FM circuit, and the output signal of each FM circuit is supplied to the two sets of the two video heads, whereby two or more kinds of tape running speeds are obtained. At each speed, the recording signal channel on the recorded tape is switched every nH, and the recording signal of the adjacent track is the same channel in the divided two input video signals. A video signal recording device characterized by.