JPH03230368A - Magnetic recording and reproducing device for color video signal and sound signal - Google Patents

Abstract

PURPOSE:To realize plural recording and reproducing modes by arranging six pieces of a magnetic head in specified positions on a circumference of a rotary cylinder at the recording time in three channels and changing relative positions of their individual recording tracks similarly to plural tape feed speeds. CONSTITUTION:On the rotary cylinder (SL) 15 to be rotated in the direction 16, six magnetic heads (HM) 17-22 are disposed symmetrically to a rotary center at 60 deg. respectively with the same relative height to a vertical plane to a rotary shaft. A magnetic tape (TM) is wound on the SL 15 more than 180 deg. to always be in contact with at least three pieces of HM, and recording signals as divided into three channels are supplied to the specified three pieces of HM to be in contact with the TM, where a video signal is recorded only for a period of half a rotation of the SL on the TM, while a sound signal in an area adjacent to a video signal area. Consequently, even when the tape feed speed is changed, recording track widths for all the pieces of HM are the same, and at the time of reproducing, the signal is restored to its original signal in the reverse process of the recording time. By this method, the recording and reproducing can be performed in plural recording modes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to magnetic recording and reproduction of color video signals and audio signals, such as video tape recorders that record and reproduce high quality color video signals and audio signals using magnetic tape. It is related to the device.

Conventional technology Conventional commercial and broadcast video tape recorders (VTRs)
In the field of (hereinafter abbreviated as ), a method has been developed for recording and reproducing a color video signal by decomposing it into two-channel component signals, a luminance signal and a color signal. For example, there are VTRs called M-format and β-CAM, and broadcast technology magazines.

The recording method described in the October issue of 1981, pages 872-890, and the recording method called MU format and described in the Technical Report VR70-2 of the Television Society, pages 7-12. It is a method.

These two-channel component type VTRs have a chrominance signal track adjacent to a luminance signal track in the recording track recorded on the magnetic tape.
Even if an azimuth angle is set between the luminance signal recording head and the chrominance signal recording head, if overwriting is performed by solid writing without a guard band, unnecessary signal components will appear as interference during playback. As a result, there is a drawback that the reproduced image quality is significantly degraded, and overwriting recording without a guard band is not currently performed. In other words, a 2-channel component VTR requires a guard band.
There is a problem that recording efficiency is poor.

Furthermore, the tape feed amount is fixed for each method,
For example, there is a problem in that it is not possible to use different recording and playback times for the same tape, such as standard mode and long-time mode in the VH3 system, which is a system for home VTRs.

An example of the conventional two-channel component type VTR mentioned above will be described below with reference to the drawings. Second
The figure is a block diagram of main parts of a conventional two-channel component VTR. In FIG. 2, a luminance signal is input to the input terminal 36.

Further, to the input terminal 37, for example, a time-base compression multiplexed color signal is input. Here, as an example of the conventional technique, a two-channel component signal is formed by a luminance signal and a time-base compression multiplexed color signal.

The luminance signal input from the input terminal 36 is sent to the FM modulator 38.
The magnetic heads 39 and 4 are frequency modulated (FM).
A reproduced luminance signal recorded on a magnetic tape at 1 and reproduced by magnetic heads 39 and 41 during reproduction is demodulated by an FM demodulator 43 and output from an output terminal 45. On the other hand, the time-base compression multiplexed color signal input from the output terminal 37 reaches the FM modulator 47 where it is FMed and recorded on a magnetic tape by the magnetic heads 40 and 42. The reproduced time-base compressed multiplex signal is demodulated by the FM demodulator 44 and outputted from the output terminal 46.

Problems to be Solved by the Invention In the conventional two-channel component VTR, a guard hand 36 exists to suppress crosstalk interference between adjacent tracks, and this has the problem that the recording density is lower than in solid writing recording or overwriting recording. be. Furthermore, there is a major problem in that it is not possible to use the recording and playback time for the same tape differently, such as the standard mode and long-time mode mentioned above.

In view of the above problems, the present invention provides two recording channels for a VTR.
By increasing the amount of information that can be recorded by increasing the number of channels to 3 channels or 4 channels or more, it is possible to record and play higher quality color video signals and audio signals, and there is no guard hand that reduces tape usage efficiency. In addition, the present invention provides a multi-channel VTR capable of recording and reproducing two or more types of time for the same tape.

Means for Solving the Problems In order to solve the above problems, in the present invention, for example, when the number of recording channels is three, six magnetic heads are placed on the circumference of the rotating cylinder from the center of rotation of the rotating cylinder. The magnetic heads 22 are arranged so that their center angles are 60 degrees, and the relative positional relationship of the center line or one end line of the recording trunk by each magnetic head 22 changes relative to the tape feed speed ↓. Yo C: Yes.

Operation The present invention has the above-described configuration, and although it is a 3,000-channel VTR that can record and play back high-quality color video signals and audio signals, it achieves high-density recording without a guard hand, and can record and play back on the same tape. To realize a VTR having two or more types of time such as a standard mode and a long time mode.

EXAMPLE An example of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of main parts in one embodiment of the present invention. The color video signal and audio signal to be recorded in this embodiment are specifically high-definition signals, but include a luminance signal and two color difference signals Cw,
Suppose that Cn + and an audio signal. In FIG. 1, for example, input terminal 1 receives a luminance signal, input terminal 2 receives a color difference signal Cw, input terminal 3 receives a color difference signal Cn, and input terminal 4 receives an audio signal. The luminance signal input from the input terminal 1 is input to the synchronization separation circuit 5, where it is separated into a horizontal synchronization signal and a vertical synchronization signal. The separated horizontal synchronization signal and vertical synchronization signal are input to the recording side reference clock generation circuit 6. In the recording side reference clock generation circuit 6, the conventionally well-known P
By operating the LL circuit, a reference clock is generated from the horizontal synchronization signal and the vertical synchronization signal, which serves as a time axis reference for the operation of each circuit's 7-rotation cylinder, capstan motor, etc. during recording. Now, the luminance signal, two color difference signals Cw and Cn inputted from the input terminals 1, 2 and 3 are led to the recording side video signal processing circuit 7, and after being converted into digital signals,
Conventionally well-known time axis compression and expansion are performed, and the signal is then stored in the memory in the recording side video signal processing circuit 7. Furthermore, the audio signal inputted from the input terminal 4 is guided to the recording side audio signal processing circuit 8, and this is also converted into a digital PCM signal by adding an error correction code etc. using a known method. , - are stored in the memory in the recording side audio signal processing circuit 8.

By the way, in this embodiment, as shown in FIG. 1, there are six magnetic heads 17, 18, . ．． 19.20.21 and 2
2 are mounted symmetrically at 60 degrees with respect to the center of rotation. Here, the track width of these six magnetic heads as a head is the same except that the azimuth is opposite to that of the adjacent magnetic head, and the azimuth is perpendicular to the rotation axis. The relative height of each head with respect to the flat plane is also the same.

Further, the magnetic tape is wound around the rotating cylinder 15 by about 180 degrees or more, and at least three heads are always in contact with the magnetic tape. In this example, the first
As shown in the figure, the recording signal is divided into three channels and is supplied to three specific magnetic heads that are in contact with the magnetic tape, and the signals are recorded on the magnetic tape by these magnetic heads. One point of the present invention lies in the recording track pattern of the recorded signal.

That is, in the present invention, since time-axis expanded or compressed video signals, whether luminance signals or color signals, are frequency modulated (FM modulated) and recorded, the signals recorded on adjacent tracks are statistically If a signal with a strong correlation is used, even if a crosstalk signal recorded on this adjacent trunk is picked up during playback, this crosstalk signal will be sufficiently attenuated due to the theory of so-called triangle noise during FM demodulation. As a result, crosstalk interference on the reproduced image quality becomes less noticeable. That is, the recording side video signal processing circuit 7 adjusts the time standard of the recording reference clock generation circuit 6, which also controls the rotational phase of the rotary cylinder 15, so as to create a track pattern that records signals with strong correlation between adjacent tracks. Based on the signal, the output of the three channels is sent to three FM
It is transmitted to modulators 9, 10 and 11. The outputs of the three FM modulators 9, 10 and 11 are transmitted to the input terminals of three switchers 12, 13 and 14, respectively. The three switchers 12, 13 and 14 have two input terminals, and the output signal of the recording side audio signal processing circuit 8 is input to the remaining terminal. The output signal of the recording-side audio signal processing circuit 8 is a PCM digital signal, and unlike a video signal, -g has no statistical correlation for each -horizontal scanning period or one vertical scanning period, for example. Therefore, it is not necessarily necessary to record an audio signal on a track adjacent to a portion where an audio signal is recorded, but as described above, a video signal may be recorded on a track adjacent to a portion where a video signal is recorded. Therefore, an audio signal is inevitably recorded in a track portion adjacent to a portion where an audio signal is recorded. The timing at which this audio signal is recorded is switched by three switches 12, 13 and 14.

As a result, in this embodiment, the video signal recording track and the audio signal recording track are switched while the magnetic head helically scans the magnetic tape.
The total recording track length corresponds to the period during which the magnetic head rotates 180 degrees on the rotating cylinder. A video signal is recorded in a reverse azimuth in a track portion adjacent to the portion where a video signal is recorded, and a track portion in which an audio signal is recorded in a reverse azimuth is adjacent to a track portion adjacent to a portion in which an audio signal is recorded. It's a pattern.

The recording track length of the video signal recording track is equivalent to the period during which the magnetic head rotates 180 degrees on the rotating cylinder, and the audio signal recording track is continuous with the track on which the video signal is recorded. The length of the recording track corresponds to the period during which the magnetic head rotates about 10 degrees to 30 degrees on the rotating cylinder, and the winding of the magnetic tape around the rotating cylinder 15 makes the angle about 200 degrees. The configuration can also be considered.

In the present invention, six magnetic heads 17, 18, 19, 20, 21 and 22 are mounted on the rotating cylinder 15 and are arranged 60 degrees symmetrically with respect to the center of rotation, so that the capstan motor Even if the rotational speed is changed to change the feeding speed of the magnetic tape, the recording track width for all heads remains the same, making it possible to record and reproduce in a plurality of recording modes. If you want to obtain playback images with ultra-high image quality and high sound quality, you can use a recording pattern with a slight guard band, or if you want to obtain playback images with high image quality and high sound quality over a long period of time, you can use a recording pattern without guard bands. It is sufficient to use a solid recording pattern. An example of a recording trunk pattern is shown in FIG.

Now, during playback, the original signal is restored by the reverse process to that during recording. In FIG. 1, the signals reproduced from the three magnetic heads are input to the reproduction side reference clock generation circuit 23, where the synchronization signal and burst signal are detected and a specific video signal or audio signal is recorded. detect the timing. The reproduction side reference clock generation circuit 23 then:
The three switchers 24, 25 and 26 are respectively switched as follows. That is, when the reproduced signal is a video signal, it passes through three FMyt modulators 27, 28 and 29, and then leads to the reproduction side video signal processing circuit 30. Further, when the reproduced signal is an audio signal, it is guided to the reproduction side audio signal processing circuit 31.

The playback side video signal processing circuit 30 and the playback side audio signal processing circuit 31 each perform signal processing almost opposite to that on the recording side, and output a luminance signal from the output terminal 32 and a color difference signal Cw from the output terminal 33 as playback signals. , a color difference signal Cn from an output terminal 34, and an audio signal from an output terminal 35, respectively.

Furthermore, if a track pattern can be detected even for a recording signal that is not recorded by a rotary cylinder with a different head arrangement, recording and reproduction compatibility can be ensured by controlling the timing of signal processing.

Effects of the Invention The present invention makes it possible to increase the number of recording channels of a VTR to three or more, increase the amount of recordable information, and record and play back higher quality video and audio signals, while also improving the number of recording channels of a VTR compared to conventional multichannel channels. It becomes possible to realize multiple recording and playback modes that were not possible with recording.

[Brief explanation of drawings]

FIG. 1 is a block diagram of main parts in an embodiment of the present invention, FIG. 2 is a block diagram of main parts in a conventional embodiment, and FIG. 3 is a recording track pattern diagram according to the present invention. 1.2.3.4... Input terminal, 5...
Synchronous separation circuit, 6... Recording side reference clock circuit, 7... Recording side video signal processing circuit, 8...
...Recording side audio signal processing circuit, 9.10.11...
...FM modulation circuit, 15...Rotating cylinder, 2
3...Reproduction side reference clock generation circuit, 27.2
8.29...FM demodulation circuit, 30...
Reproducing side video signal processing circuit, 31... Reproducing side audio signal processing circuit, 32, 33.34.35... Output terminal.

Claims (22)

[Claims] (1) A means for inputting color video signals and audio signals and converting them into 3-channel signals that can be recorded on magnetic tape, and supplying them to the rotating cylinder by changing the rotational speed of the kip stun motor using a changeover switch. means for varying the feeding speed of the magnetic tape; and a rotating cylinder around which the magnetic tape is wound at an angle of about 180 degrees or more, and which rotates by N/2 for every field of the color video signal, where N is a positive integer. and six magnetic heads arranged 60 degrees symmetrically with respect to the central axis of the rotary cylinder and whose track ends have the same relative height with respect to a plane perpendicular to the rotation axis of the rotary cylinder. ,
The recordable signals of the three channels are supplied to at least three of the six magnetic heads that are in contact with the magnetic tape, and the video signal is recorded on the magnetic tape during a period in which the rotating cylinder makes about half a rotation. and the audio signal is recorded in an area adjacent to the area where the video signal is recorded, and the reproduction means and the reproduced signal are exchanged again into the input color video signal and audio signal. 1. A magnetic recording and reproducing device for color video signals and audio signals, which outputs color video signals and audio signals. (2) The input color video signal and audio signal having one field period length are subjected to time axis expansion and compression processing.
The color video signal according to claim 1, wherein the color video signal is converted into a recordable three-channel signal having a length of one field period, and is recorded during a period in which each of the six magnetic heads rotates 180 degrees on a rotating cylinder. and a magnetic recording and reproducing device for audio signals. (3) The input color video signal with a length of 1 field period is converted into a recordable 3-channel signal with a length of 1 field period through time axis expansion and compression processing, and six magnetic heads are respectively placed on a rotating cylinder. A claim characterized in that an audio signal having a length of one field and inputted during a period of rotation of 180 degrees is recorded in an area adjacent to an area on the magnetic tape in which the color video signal is recorded. The magnetic recording and reproducing device for color video signals and audio signals according to item (1). (4) The magnetic heads to be driven are switched one by one in the rotational direction opposite to the rotational direction of the rotary cylinder every time the rotary cylinder rotates 60 degrees. Magnetic recording and reproducing device for color video and audio signals. (5) Magnetic recording of color video signals and audio signals according to claim (1), wherein the signal format when the color video signal is recorded is a frequency-modulated luminance signal and two color difference signals. playback device. (6) Magnetic recording of color video signals and audio signals according to claim (1), wherein the signal format when the color video signal is recorded is a frequency-modulated luminance signal and a line-sequential color difference signal. playback device. (7) The recording trunk pattern is determined so that the frequency-modulated luminance signal and two color difference signals recorded on the magnetic tape have a statistically high correlation with the signals recorded on adjacent tracks. Claim (5) characterized in that
) or (6), the magnetic recording and reproducing device for color video signals and audio signals. (8) The color signal according to claim (1), wherein the signal form when the audio signal is recorded is a digital signal obtained by adding an error correction code to the digitized audio signal and modulating the signal. Magnetic recording and reproducing device for video and audio signals. (9) The magnetic recording and reproducing device for color video signals and audio signals according to claim (1), wherein all six magnetic heads have the same head track width. (10) The color video signal according to claim (1), wherein each of the six magnetic heads has an azimuth opposite to that of an adjacent magnetic head whose central angle with respect to the cylinder center is 60 degrees. and a magnetic recording and reproducing device for audio signals. (11) Magnetic recording and reproduction of color video signals and audio signals according to claim (1), wherein N, which is a positive integer, is 1, and the rotating cylinder rotates half a rotation for every one field of the color video signal. Device. (12) Means for inputting color video signals and audio signals and converting them into M-channel signals recordable on magnetic tape, where M is a positive integer greater than 3, and rotational speed of the capstan motor using a changeover switch. means for varying the feeding speed of the magnetic tape fed to the rotary cylinder by changing the speed of the magnetic tape;
It is provided with a rotating cylinder that is wound by 0 degrees or more and rotates by N/2 for each field of the color video signal, where N is a positive integer, and (180/M) with respect to the central axis of the rotating cylinder. 2M magnetic heads arranged symmetrically and having the same relative height of track ends with respect to a plane perpendicular to the rotation axis of the rotary cylinder, and recordable signals of the M channels are transmitted to the 2M magnetic heads. The video signal is supplied to at least M magnetic heads that are in contact with the magnetic tape among the magnetic heads, and the video signal is recorded on the magnetic tape for a period during which the rotary cylinder makes half a rotation, and the audio signal is recorded on the magnetic tape during the half-rotation period of the rotary cylinder. A color video signal, characterized in that the color video signal is recorded in an area adjacent to the recorded area and also reproduced, and the reproduced signal is converted back into the inputted color video signal and audio signal and outputted. and a magnetic recording and reproducing device for audio signals. (13) The input color video signal and audio signal with a length of one field period are converted into recordable M-channel signals with a length of one field period by time axis expansion and compression processing, and the M magnetic heads are 13. A magnetic recording and reproducing apparatus for color video signals and audio signals according to claim 12, wherein the recording is performed during a period of rotation of 180 degrees on a rotating cylinder. (14) The input color video signal with a length of one field period is converted into a recordable M-channel signal with a length of one field period by time axis expansion and compression processing,
The input audio signal, which is recorded during the period when each of the M magnetic heads rotates 180 degrees on the rotating cylinder and has a length of one field period, is adjacent to the area on the magnetic tape where the color video signal is recorded. 13. The magnetic recording and reproducing apparatus for color video signals and audio signals according to claim 12, wherein the magnetic recording and reproducing apparatus for color video signals and audio signals is recorded in a region. (15) The magnetic head to be driven has a rotary cylinder (1
Magnetic recording of color video signals and audio signals according to claim 12, characterized in that the rotation direction is switched one by one to the rotation direction opposite to the rotation direction of the rotary cylinder each time the rotation cylinder rotates by 80/M) degrees. playback device. (16) The signal format when a color video signal is recorded is
13. The magnetic recording and reproducing apparatus for color video signals and audio signals according to claim 12, wherein the signals are a frequency-modulated luminance signal and two color difference signals. (17) The signal format when a color video signal is recorded is
13. The magnetic recording and reproducing apparatus for color video signals and audio signals according to claim 12, wherein the signals are a frequency-modulated luminance signal and a line-sequential color difference signal. (18) The recording track pattern is determined so that the frequency-modulated luminance signal and the two color difference signals recorded on the magnetic tape have a statistically high correlation with the signals recorded on adjacent tracks. A claim characterized in that (
16) or the magnetic recording and reproducing device for color video signals and audio signals according to any one of (17). (19) The signal form when an audio signal is recorded is to add an error correction code to the digitized audio signal, and
13. The magnetic recording and reproducing apparatus for color video signals and audio signals according to claim 12, wherein the signals are modulated digital signals. (20) The magnetic recording and reproducing apparatus for color video signals and audio signals according to claim (12), wherein the head track widths of the 2M magnetic heads are all the same. (21) According to claim (12), each of the 2M magnetic heads has an azimuth opposite to that of an adjacent magnetic head whose central angle with respect to the cylinder center is (180/M) degrees. Magnetic recording and reproducing device for color video and audio signals. (22) Magnetic recording and reproduction of color video signals and audio signals according to claim (12), wherein N, which is a positive integer, is 1, and the rotating cylinder rotates half a rotation for every one field of the color video signal. Device.