JPH02230586A - System and device for magnetic recording and reproduction - Google Patents

Abstract

PURPOSE:To match the timing of reproducing scenes from plural VTRs in frame unit desirably by setting the feed phase relation of a tape so that timing codes reproduced from reference and sub magnetic recording and reproducing means with the same timing can be set at desirable relation. CONSTITUTION:When no prescribed relation exists between indexes reproduced from the reference magnetic recording and reproducing means(code (a) is attached) and the sub magnetic recording and reproducing means(code (b) is attached), the fast feed and rewinding of a magnetic tape 13b by the sub magnetic recording and reproducing means are performed by a first adjusting means 15 so that the prescribed relation between those indexes can be obtained. When the prescribed relation is obtained, the fine adjustment of the feed of the magnetic tape 13b of the sub magnetic recording and reproducing means is performed by a second adjusting means 14 so that the prescribed relation between the time codes in reproducing video signals can be obtained by the reference and sub magnetic recording and reproducing means. Thereby, it is possible to match the timing of desired scenes reproduced from the plural VTRs in frame unit.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention uses a plurality of magnetic recording and reproducing devices (hereinafter referred to as VTRs) to splice and synthesize the respective reproduced video signals. The present invention relates to a magnetic recording/reproducing system and a magnetic recording/reproducing device.

[Conventional technology]

For example, if you want to select scenes recorded on two tape cassettes and edit and record them on another tape cassette, you can do this by using three VTRs. In this case, you can use one VTR as a recording VTR and attach a recording tape cassette, and use the other two VTs as a recording tape cassette.
R is used as a playback VTR, and a recorded tape cassette with each scene recorded on it is installed, and while the playback VTR plays back the recorded tape cassette, the recording VTR records these playback video signals onto the recording tape cassette. It is something to do.

When performing such editing, the playback VTR cues the required scene on the recorded tape cassette, and then one of the playback VTRs performs phase control based on the recording VTR, and then starts recording this recorded video. The required scene is recorded on the recording tape cassette from the beginning of the scene that has already been completed, and near the end of this scene, the other playback VTR starts playing with phase control based on the recording VTR, and at the end of this scene, the second To switch reproduction video signals of two reproduction VTRs.

According to this, in the recording tape set 1, it is possible to smoothly join and record the necessary scenes in two recorded tape cassettes, and to edit without disturbing the screen at the joints such as the assembly and insert. .

In addition, by putting two playback VTRs into playback mode at the same time and combining these playback video signals using an appropriate method,
Each scene can be recorded on the recording tape cassette 1 as a video signal that is displayed after being synthesized by recording division, fading, etc.

[Problem to be solved by the invention]

By the way, when editing or composite recording of necessary scenes from multiple recorded tape cassettes onto one recording tape cassette as described above, it is necessary to cue the necessary scenes for the corresponding pre-recorded tape set. However, when actually recording these scenes, when editing and recording, it is necessary to make sure that the end timing of the scene being recorded and the start timing of the next scene to be recorded match exactly. , i.e. pieces (frames or fields)
VTR so that the timing of two scenes matches each other
It is very difficult to control the scene, and this can result in some recording being omitted at the beginning or end of the scene, or unnecessary images being recorded before the beginning or after the end of the scene. Furthermore, when performing screen composite recording, there is a problem in that a timing shift occurs between corresponding screens between scenes.

It is also possible to reduce the noise in the reproduced video signal by recording the same scene on two tape sets 1, reproducing them simultaneously, and adding the respective reproduced video signals. According to this, an excellent effect of preventing afterimages, which cannot be obtained with conventional circuit noise reducers, can also be obtained. However, even in this case, it is impossible to avoid the timing difference between the two reproduced video signals, and if there is a difference of even one frame, the noise reduction effect will be significantly impaired.

It is an object of the present invention to solve such problems and to
An object of the present invention is to provide a magnetic recording and reproducing system and a magnetic recording and reproducing apparatus that can adjust the timing of scenes reproduced from frame to frame as desired.

[Means to solve the problem]

In order to achieve the above object, the magnetic recording and reproducing system according to the present invention records a video signal to which a time code whose contents change sequentially for each frame (or one field) is recorded, and also displays a position on a control track. A plurality of magnetic recording and reproducing means for reproducing a magnetic tape on which an index is recorded, and any one of the magnetic recording and reproducing means is used as a reference magnetic recording and reproducing means, and any other one is used as a subordinate magnetic recording and reproducing means. the sub-magnetic recording/reproducing means so that the index reproduced by the reference magnetic recording/reproducing means and the index reproduced from the sub-magnetic recording/reproducing means at the same timing have a desired relationship; a first adjusting means for coarsely adjusting the running of the magnetic tape; a time code that starts operating upon completion of the adjusting operation of the first adjusting means and is reproduced by the reference magnetic recording/reproducing means; a second adjusting means for finely adjusting the running of the magnetic tape in the subordinate magnetic recording and reproducing means so that the time code reproduced from the subordinate magnetic recording and reproducing means at the same timing has a predetermined relationship; Consists of.

Further, the magnetic recording redistribution system according to the present invention includes a servo control means for controlling the phase of the magnetic tape and the rotating video head, and a time code whose contents change sequentially for each frame (or one field) is added to the magnetic tape. a plurality of magnetic recording and reproducing means for reproducing video signals, any one of the magnetic recording and reproducing means being a reference magnetic recording and reproducing means, and the other arbitrary one being a secondary magnetic recording and reproducing means, the reference; Time code comparison means that compares the contents of the time codes reproduced by the secondary magnetic recording and reproducing means, outputs a difference detection signal when the two do not have a predetermined relationship, and outputs a coincidence signal when the two have a predetermined relationship. A reference signal serving as a phase reference is supplied to the reference and the servo control means of the slave magnetic recording and reproducing means, respectively, and a reference signal to the slave magnetic recording and reproducing means is supplied to the slave magnetic recording and reproducing means by the difference detection signal outputted by the time code comparing means. A reference signal circuit configured to increase or decrease the frequency and output the matching signal by the time code comparison means to correct the phase shift between the reference and the vertical synchronization signal of the video signal reproduced by the sub-magnetic recording and reproducing means. do. The phase shift of the vertical synchronization signal can be corrected by changing the reference signal to the slave magnetic recording/reproducing means based on the phase comparison result of the vertical synchronizing signal or the head switching signal, or by changing the reference signal to the slave magnetic recording/reproducing means. The reference signal may have the same frequency and the same phase as the reference l6 signal on the magnetic recording/reproducing means side.

Furthermore, the magnetic recording/reproducing system according to the present invention has a plurality of magnetic recording/reproducing means, and when there is almost no remaining tape remaining, the next magnetic recording/reproducing means is set to the recording mode.
A video signal to which a time code whose contents change sequentially for each frame (or field) is recorded is recorded, and when the remaining tape capacity of the plurality of magnetic recording and reproducing means becomes almost empty, the next magnetic recording and reproducing means is used. The video signal to which the time code has been added is sequentially reproduced so that the magnetic recording and reproducing means enters the reproduction mode, and when the next magnetic recording and reproducing means enters the reproduction mode, the reproduction mode precedes the reproduction time code. The servo reference signal is controlled so that the content matches the reproduction time code of the magnetic recording and reproduction means.

The magnetic recording and reproducing device according to the present invention is a magnetic recording and reproducing device that performs phase synchronization with a reference video signal from a desired video source to which a time code whose contents change sequentially for each frame (or one field) is added, and is controlled by servo control. A magnetic recording/reproducing means for reproducing a video signal to which a time code whose content changes sequentially for each frame (or one field) is added from a magnetic tape by a circuit, and comparing the time code of the reproduced video signal and the reference video signal. and when the difference between the time codes is larger than a predetermined value, the first signal is sent, and when the difference between the time codes is not zero and is equal to or less than the predetermined value, the second signal is sent.
time code comparison means for respectively generating a third signal when the difference between the time codes is zero; phase comparison means for comparing the phases of the vertical synchronization signals of the reproduced video signal and the reference video signal; and the time code comparison means. control means for controlling the servo control circuit to run the magnetic tape at high speed in accordance with the output of the first signal of the time code comparison means; generating a reference signal whose frequency increases or decreases in accordance with the output signal of the phase comparison means; and a reference signal circuit which uses as a phase reference signal of the servo control circuit.

[For production]

In the first aspect of the invention, when there is no predetermined relationship between the indexes reproduced from the reference magnetic recording/reproducing means and the subordinate magnetic recording/reproducing means, the first adjusting means adjusts the relationship between the indexes. The magnetic tape is fast-forwarded by the corresponding magnetic recording/reproducing means so that a predetermined relationship is obtained.
Rewinding is performed. When the predetermined relationship is obtained, the second adjustment means is then adjusted so that the time codes in the reproduced video signal are in the predetermined relationship by the reference magnetic recording and reproducing means and the subordinate magnetic recording and reproducing device. The running of the magnetic tape of the slave magnetic recording/reproducing means is adjusted by this.

As a result, the desired scenes reproduced from the reference magnetic recording/reproducing means and the sub-magnetic recording/reproducing means match the timing of the desired frames, and the screen division table and composition for noise reduction are performed. It can be done correctly, and even in editing, it is possible to stitch together any desired location without missing any frames or adding unnecessary frames.

In the magnetic recording/reproducing system according to the second aspect of the invention, the recording position of a desired scene on the magnetic tape (reference magnetic tape) in the reference magnetic recording/reproducing means is designated by the time code on this magnetic tape. The recording position of a desired scene on the magnetic tape (secondary magnetic tape) in the second magnetic recording/reproducing means is also specified by the time code on this magnetic tape. Therefore, the time code at a specific recording position such as the start or end of the desired scene on the reference magnetic tape and the time code at a specific recording position of the desired scene on the secondary magnetic tape are simultaneously reproduced. By adjusting the running condition of the secondary magnetic tape,
Each desired scene can be reproduced from the reference and slave magnetic tapes in a timely manner on a frame (or field) basis. After such adjustment, the vertical synchronizing signals of the reproduced video signals from the reference and slave magnetic tapes are aligned in phase.

Therefore, the desired scene played back from the reference and slave magnetic tapes will have the same timing between the desired frames, and the screen division table and composition for noise reduction will be performed correctly, and editing will be performed correctly. Also, any desired scene can be spliced together without missing any frames or adding unnecessary frames.

Further, in the magnetic recording and reproducing system according to the third aspect of the invention, video signals are sequentially recorded on different magnetic tapes, but when recording is transferred between two magnetic tapes, both of these magnetic tapes are in a recording mode for a predetermined period of time. Thus, overlap recording is performed in which the same video signal is recorded at the same time. Although a time code is added to this video signal, in the overlap recording section of these magnetic tapes,
Frames with the same information content to which the same time code is added are recorded on each magnetic tape.

Then, when playback is performed on one magnetic tape and this overlap recording section is reached, playback is performed on the other magnetic tape. By adjusting the running state of the magnetic tapes that have started, frames with the same content will be played back from these magnetic tapes at the same timing, and at this time, the played video signal will be transferred from one side of the magnetic tape to the other. By switching, the information content of the video signal at this switching point changes continuously.

Therefore, even if video signals are sequentially reproduced from a plurality of magnetic tapes, an unnatural change in information content does not occur at the time of switching between magnetic tapes, and it appears as if they were being reproduced from a single magnetic tape.

In the magnetic recording and reproducing apparatus according to the present invention, when the difference in time code between the reference video signal and the reproduced video signal is larger than a predetermined value, the magnetic tape is moved in the forward direction so that the difference quickly falls within the predetermined value. Or the vehicle is driven in the opposite direction at high speed. When this difference falls within a predetermined value, the frequency of the servo reference signal used for phase control of the magnetic tape during normal playback is increased or decreased so that the above time codes match.
The running of the magnetic tape is controlled. Due to this. The reproduced video signal matches the reference video signal in timing on a frame (or field) basis.

Thereafter, the frequency of the servo reference signal increases or decreases in accordance with the phase difference between the vertical synchronization signal between the reference video signal and the reproduced video signal.
As a result, these vertical synchronization signals are also phase-synchronized.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the magnetic recording and reproducing system according to the present invention, in which 1 is a TBC (time base collector), 2 is a synthesizer, 3 is a time code circuit, 4.
5 is a comparison circuit, 6a, 6b is a signal processing circuit, 7a, 7b
, 8a, 8b are rotating video heads, 9a, 9b are cylinder motors, 10a, 10b are servo control circuits, lla
, llb are capstan motors, 12a, 12b are C
TLP (:I troll signal) detector, 13a,
13b is a magnetic tape, 14 is a reference signal circuit, 15 is a system controller, 16 is a coincidence indicator, and l7 is an input terminal.

In this embodiment, two reproduction VTRs are used, and these are distinguished by the symbols a and b.

In the figure, one of the reproduction VTs marked with a
In R, the speed and phase of the capstan motor Ila and the cylinder motor 9a are controlled by the servo control circuit 10a to which the servo reference signal S8 is supplied from the reference signal circuit 14, and the magnetic tape 13a is driven to travel by the capstan motor Ila. The rotary magnetic heads 7a and 8a alternately reproduce and scan the magnetic tape 13a by the cylinder motor 9a.

The reproduced video signals from the rotating magnetic heads 7a, 8a are spliced into a continuous video signal signal by a signal processing circuit 6a, and are further subjected to processing such as demodulation. Similarly,
In the other reproduction VTR to which the signal b is attached, the capstan motor 1lb is controlled by the servo control circuit 1'Ob to which the servo reference signal Sb is supplied from the reference signal circuit 14.
and cylinder motor 9b are controlled in speed and phase, magnetic tape 13b is driven to run by capstan motor llb, and rotating magnetic head 7b . 8b alternately reproduces and scans the magnetic tape 13b. The reproduced video signals from the rotating magnetic heads 7b and 8b are spliced into a continuous video signal by a signal processing circuit 6b, and are further subjected to processing such as demodulation.

Here, on the magnetic tapes 13a and 13b, a time code and a CTL are stored in advance as tape position information at the time of recording.
P index is recorded. The time code is
For example, see "Japan Broadcasting Corporation 1 rVTR Technology" published by Japan Broadcasting Publishing Association (March 1981) 2nd edition pp. 226-2
V ITC (Vertical
Interval Time Code) is a code that is inserted into the vertical blanking period of each frame of a video signal and is used to number each frame in order. VITC is standardized to be inserted in frame units, but it may also be a time code inserted in field units. In addition, the CTLP index is, for example, the VASS (VHS
．． Address Search System). It is a code that is added to the CTLP to represent the address on the magnetic tape, and the duty ratio of the CTLP is divided into two types, one being a "0" bit and the other being a1.
One address value is represented by a combination of bits. Therefore, on the magnetic tape, the address value based on the CTLP index changes by 1 for each plurality of frames of the video signal recorded on the magnetic tape.

Therefore, in FIG. 1, the magnetic tapes 13a, 13
When the rotating magnetic heads 7a, 8a and the rotating magnetic heads 7b, 8b run and reproduce signals, a time code is generated during the vertical blanking period for each frame (or one field) of the video signal reproduced from these. It is included. Moreover, CTLP detectors 12a and 12b
As a result, the CTLP including the CTLP index is reproduced from the magnetic tapes 13a and 13b, respectively.

By the way, the magnetic tape 13 to be synthesized or edited
A certain scene P recorded on the magnetic tape 13b and a certain scene Q recorded on the magnetic tape 13b generally have different address values of their recording positions (that is, address values of the time code and CTLP index). These scenes P,
When composing or editing Q, it is necessary to set the playback timings of these in a predetermined relationship, and for this purpose, time codes and CTLP indexes are used.

That is, if the VTR to which the symbol a is attached is the reference VTR, the magnetic tape 13a of this reference VTR
The difference between the address value of the CTLP index representing the recording position of scene P on the magnetic tape 13b of the other VTR and the address value of the CTLP index representing the recording position of scene Q on the magnetic tape 13b of the other VTR is set as an offset value in the comparator circuit 5, and , the magnetic tape 13 for the address value of the time code representing the recording position of the scene P on the magnetic tape 13a.
The difference between the time code address values representing the recording position of scene Q at point b is set in the comparison circuit 4 as an offset value.

After that, the system controller 15 operates the servo control circuits 10a, 10b, and the magnetic tapes 13a,
13b is run. As a result, the CTLP detector 12
CTLP is reproduced from the magnetic tapes 13a and 13b by the magnetic tapes 13a and 12b, and is supplied to the comparator circuit 5. The comparison circuit 5 detects CTLP indexes from these CTLPs, corrects their address values with a preset offset value, and compares the magnitude relationship. This comparison result is supplied to the system controller 15, and if these address values corrected by the offset value do not match, the system controller 15 controls the servo control circuits 10a and 10b to rewind or fast forward the magnetic tape 13b. The above address values in the comparison circuit 5 are made to match. For example, suppose that the address value of the CTLP index changes by 1 every several hundred frames, and the rotating magnetic heads 7a, 8 on the magnetic tape 13a
The difference between the number of frames from the current scanning position of a to the recording position of scene P and the number of frames from the current running position of the rotating magnetic heads 7b, 8b on the magnetic tape 13b to the recording position of scene Q is 2,000-odd frames. The magnetic tape 13a
, 13b, even if corrected by the offset value, there is a difference of 4, then the magnetic tape 1 is adjusted so that this difference becomes zero.
3b is fast forwarded or rewound. As a result, scene P. The playback timing relationship for Q is set within an error range of several hundred frames from the defined relationship.

In this way, rough timing alignment between scenes P and Q is performed. The prescribed playback timing relationship for scenes P and Q differs depending on whether they are combined or edited. In the case of compositing, the playback timing is the same at the beginning of scenes P and Q, and in the case of editing, the playback timing is the same at the end of one of scenes P and Q and the start of the other. It is.

When the rough timing adjustment is completed as described above and the detection result of the comparator circuit 5 becomes zero, the system controller 15 controls the servo control circuits 10a . 10b are respectively connected to the servo reference signal S.10b of a specified frequency from the reference signal circuit 14. ，
S. The time code circuit 3 and the comparator circuit 4 are operated by putting each VTR into a normal playback state.

Therefore, the reproduced video signals from the signal processing circuits 6a and 6b are supplied to the reference signal circuit 14 and the time code circuit 3. A time code circuit 3 separates time codes from each reproduced video signal, and a comparator circuit 4 corrects these address values with a preset offset value and compares them in magnitude. In these address values corrected by the offset value, if the address value of the time code reproduced from the magnetic tape 13b is larger than the address value of the time code reproduced from the magnetic tape 1.3a, the address value of the time code reproduced from the magnetic tape 1.3a is This means that the magnetic tape 13b is leading, and in the opposite case, the magnetic tape L3b is behind. The comparison circuit 4 includes magnetic tapes 13a, 13
If there is a delay or lead between b, a difference detection signal A is output, and if there is no delay or lead, a match signal B is output.

Assuming that the magnetic tape 13b is ahead of the magnetic tape 13a by several hundred frames in time code value, a difference detection signal A representing this is supplied to the reference signal circuit 14. The reference signal circuit 14 supplies servo reference signals S- and Sb of the same frequency to the servo control circuits 10a and 10b, respectively, but the comparison circuit 4 supplies a difference detection signal A indicating that the magnetic tape 13b is advancing. If so, lower the frequency of the servo reference signal S (several percent).
degree). As a result, the running speed of the magnetic tape 13b is lowered than the normal reproduction running speed, and the magnetic tape 13a operates to catch up with the magnetic tape b.

When the magnetic tape 13a catches up with the magnetic tape 13b and the address values corrected by the offset value of the time code from them match, the comparator circuit 4 outputs a match signal B. As a result, the reference signal circuit 14 becomes the signal processing circuit 6a.
, 6b, and increases or decreases the frequency of the servo reference signal S, according to the phase relationship, so that the servo signals are in phase with each other. Controls the control circuit 10b.

Conversely, if the magnetic tape 13a is ahead, the reference signal circuit 14 increases the frequency of the reference signal S, based on the difference detection signal A of the comparator circuit 4 indicating this.

In the above manner, the time code address values of each frame in scenes P and Q, including the offset value, match, and fine timing adjustment is performed on a frame-by-frame basis. Further, the phase of the vertical synchronization signal also matches for each frame.

In this embodiment, the magnetic tape 1 operates as described above.
When desired scenes 3a and 13b are to be synthesized for split-screen display, noise reducer, etc., the difference between the time code address values at the beginnings of these scenes is set as an offset value in the comparator circuit 4, and The difference between the address values of the CTLP indexes may be used as the offset value set in the comparator circuit 5. By setting these offset values in the comparator circuit 4.5 to perform the above operation, the magnetic tape 13a.
The reproduced video signal of the desired scene 13b is output with timings matching from the first frame to the vertical synchronizing signal, that is, with timings matching frame by frame. The reproduced video signals output from the signal processing circuits 6a and 6b are TBCI
The time axis is corrected so that they match in units of one horizontal scanning period.

As described above, when even the phases of the vertical synchronization signals match, the reference signal circuit 14 sends a stable coincidence signal D to the coincidence indicator 16.
and display it. This coincidence signal D is also supplied to the synthesizer 2, and during the period when this coincidence signal D is being supplied, that is, when the coincidence display 16 is providing a stable display, the input terminal is The control signal supplied from 17 causes the combiner 2 to
The two reproduced video signals are combined and supplied to another VTR or monitor receiver.

In the case of assembly or insert editing in which desired scenes of the magnetic tapes 13a and 13b are spliced, the difference in time code address values at the end of the preceding scene and the beginning of the scene to be spliced is sent to the comparator circuit 4. The above operation is performed using the offset value to be set and the difference between the address values of the CTLP index as the offset value to be set in the comparator circuit 5.

That is, if it is assumed that the desired scene on the magnetic tape 13a now precedes, the VTR on the side marked with the symbol a performs normal playback as the reference VTR, and the video signal of the scene on the magnetic tape 13a is output from the synthesizer 2. be done. During this time, in the VTR on the side marked b, the comparator circuit 5 and the system controller 15 fast-forward or rewind the magnetic tape 13b, and the magnetic tape 13a . 13
Rough timing adjustment is performed so that the difference between the address values of the reproduced CTLP indexes of b is equal to the offset value set in the comparator circuit 5. When this is completed, the comparator circuit 4 and the reference signal circuit 14 perform magnetic The running speed of the tape 13b is increased or decreased in the forward direction, and fine timing adjustment is performed so that the difference in the address values of the reproduction timings of the magnetic tapes 13a and 13b becomes equal to the offset value set in the comparator circuit 4.

When this is completed, the TBCI causes the magnetic tape 13a to
．． The reproduced video signal 13b has the same timing on a frame-by-frame basis, and the horizontal synchronization signal also has the same phase.

The above operations are performed until the end of the desired scene on the magnetic tape 13a is reproduced, and at this end, the synthesizer 2 switches from the reproduced video signal of the magnetic tape 13a to the reproduced video signal of the magnetic tape 13b and outputs it. As a result, the starting end of the magnetic tape 13b is correctly spliced to the end of the desired scene on the magnetic tape 13a for reproduction.

The magnetic tape 1 is placed between two desired scenes on the magnetic tape 13a.
Insert for inserting the desired scene of 3b [In the case of 1 collection or when multiple desired scenes are recorded on the magnetic tapes 13a and 13b, assembly editing that alternately plays back and splices the desired scenes from the magnetic tapes 1.3a and 13b. In this scene, the VTR that normally reproduces the desired scene becomes the reference VTR, and during this reproduction, the coarse timing adjustment and fine timing adjustment described above are performed on the other VTR.

That is, the desired scene currently recorded on the magnetic tape 13a is displayed as P+. Pz, the desired scene recorded on the magnetic tape 13b is Q1, and the desired scene recorded on the magnetic tape 13b is spliced in the order of P1Q+ and Pz. First, the VTR on the side marked with the symbol a records the scene P+ from the magnetic tape 13a as base 1vrR. is played normally, while, as above, the sign b
Coarse timing adjustment and fine timing adjustment are performed on the side of the VTR whose side is turned on. At the end of scene P, when the synthesizer 2 switches from the reproduced video signal of scene P1 on the magnetic tape 13a to the reproduced video signal of scene Q1 on the magnetic tape 13b, the V on the side marked b
The TR performs normal playback operation as a reference VTR. During this time, the difference between the address values of the OCTLP index at the end of scene Q1 and the start of the next scene P2 on the magnetic tape 13a is set in the comparison circuit 5 as an offset value, and the difference between the address values of the time code is compared as an offset value. set in circuit 4, system controller 15 and reference signal circuit 1
4, the VTR on the side marked with the symbol a performs coarse timing adjustment and fine timing adjustment. Then, when the synthesizer 2 switches the reproduced video signal at the end of the scene Q, the VTR on the side marked with the symbol a
performs normal playback operation as the reference VTR, and the other VT
In R, coarse timing adjustment and fine timing adjustment are performed for the next case to be spliced.

In the manner described above, scenes can be synthesized and edited.

FIG. 2 is a block diagram showing an example of the reference signal circuit 14 in FIG. 1, in which 1st is an oscillator, 1920 is a counter, 20. 22 is a vertical synchronization signal detector, 23 is a phase comparator. 24. 25 is a switch. 26 is a switch signal generator, and parts corresponding to those in FIG. 1 are given the same reference numerals.

In the figure, the output signal of the oscillator 18 is transmitted to the counter 19,
Servo reference signal S88b
is generated. The frequency division ratio of the counters 19 and 20 is determined by the servo reference signal S. ,S so as to vary around the frequency at which each VTR in Fig. 1 is set to the normal playback state.
It is set to be variable.

The difference detection signal A of the comparison circuit 4 (FIG. 1) is supplied to the a side of the switch 24. Further, the output video signal of the signal processing circuit 6a6b is transmitted to the vertical synchronization signal detector 21. 22, and the vertical periodic signals VSI and VS2 are separated. The phase comparator 23 compares the phases of these vertical synchronizing signals VSI and VS2. Here, the phase comparator 23 is controlled by the switch signal SWI which is inverted every falling edge of the "H" coincidence signal B by the switch signal generator 26, and when the switch signal SW1 is "I", the vertical synchronization signal This difference indicates whether the vertical synchronization signal VS2 is ahead or behind VSI, and also indicates whether the vertical synchronization signal VS1 is ahead or behind the vertical synchronization signal VS2 when the switch signal SWI is "L". Outputs detection signal C.

This difference detection signal C is supplied to the b side of the switch 24.

The switch 24 is controlled by the match signal B from the comparison circuit 4, and when there is no "H" match signal B, it selects the difference detection signal A on the a side, and when there is a match signal B, it selects the difference detection signal C on the b side. select. The difference detection signal selected by the switch 24 is sent to the counter 19 or 20 via the switch 25.
is supplied to The switch 25 is a switch signal generator 26
When this switch signal SWI is "H", it is closed to the d side, and when it is 'L', it is closed to the C side.

The counters 19 and 20 output the servo reference signal S. when the difference detection signal is not supplied from the switch 25 or when it is zero even if it is supplied. ,S. The frequency of each magnetic tape 13a
, 13b (FIG. 1) is set such that the frequency is such that the servo reference signal S. , Sb is different from the above by a predetermined amount.

Therefore, as shown in FIG. 3, the switch signal SW
1 is "L" and the switch 25 is closed to the C side, the VTR on the side labeled b in FIG. 1 becomes the reference VTR, and the magnetic tape 13b receives the servo reference signal S.
, the vehicle runs at the normal regeneration speed. On the other hand, code a
For the VTR marked with , after the rough timing adjustment described above is completed, the phase comparator circuit 4 (Fig. 1)
The servo difference detection signal A is supplied to the counter 19 via the switch 24, which is closed to the a side, and further via the switch 25, and the servo reference signal S. frequency is changed. As a result, the running speed of the magnetic tape 13a is changed to perform fine timing adjustment.

After that, when the match signal B is supplied, the switch 24 switches to b.
and the vertical synchronizing signal VS from the phase comparator 23
A difference detection signal C representing the lead or lag of the vertical synchronizing signal VSI with respect to VSI is supplied to the counter 19, and the phase of the vertical synchronizing signal is adjusted.

After that, when the next offset value is set in the comparator circuit 4.5, the match signal B falls, the switch 24 is switched to the a side, and the switch signal SWI is set to "H".
As a result, the switch 25 is switched to the d side. This results in
The VTR on the side labeled a in FIG. 1 serves as a reference VTR, and fine timing adjustment and vertical synchronization signal phase adjustment of the other VTR are performed.

In the case of editing, it goes without saying that the level of the switch signal SWI is preset depending on which VTR in FIG. 1 is to be used as the reference VTR first. Further, when the vertical synchronization signals VSI, VS2 are phase synchronized, the phase comparator 23 outputs a coincidence signal D to be supplied to the coincidence indicator 16, and outputs a coincidence signal D to be supplied to the coincidence indicator 16,
It is displayed that the phases of S2 match.

FIG. 4 is a block diagram showing another specific example of the reference signal circuit 14 according to the present invention, in which 27 is an oscillator, 28 . 2
9 is a counter, 30. 31 is a switch, 32 is a switch signal generator, 33 is a T-type flip-flop circuit (hereinafter referred to as TFF), 34. 35 is an inverter, 36.
37 is an AND gate.

In the figure, the output signal of the oscillator 27 is transmitted to the counter 28,
The output signal of the counter 28 is divided by the switch 30 . 31, the output signal of the counter 29 is connected to the switch 30. 31 are respectively supplied to the b side. counter 2
9 is the counter 19. of FIG. 20, the frequency division ratio is variable and is controlled by the difference detection signal A from the phase comparison circuit 4 (FIG. 1).
has a fixed frequency division ratio, and this frequency division ratio is determined by the servo reference signal S.D when the VTR in FIG. , Sb is set so that a signal having the same frequency as that of Sb can be obtained. The coincidence signal B is output from the phase comparator circuit 4 and the difference detection signal A is output.
When is zero, the frequency division ratio of the counter 29 is equal to that of the counter 28.
is equal to the division ratio of

Switch 30. 31 is controlled by the switch signal generator 32, and as shown in FIG. 5, it closes to the b side when the switch signals SWa and SWb from the switch signal generator 32 are "H", and closes to the a side when they are "L". shall be taken as a thing. The switch signal generator 32 includes a TFF 33 that is triggered by the rising edge of the match signal B, inverters 34 and 35 that invert the level of the match signal B, and an output signal of the inverter 34 and the TF.
AND gate 36 to which the Q output of F33 is supplied;
It consists of an AND gate 37 to which the output signal of the inverter 35 and the Q output of the TFF 33 are supplied.
The switch signal SWa, which is “H” during the second period, is
From the D gate 37, a switch signal SWb which similarly becomes "H" for every other period is obtained.

Therefore, it is assumed that the rough timing adjustment described above has been completed using the VTR on the side where the symbol a in FIG. Then, in FIG. 5, the switch signal S
Wa is held at "L" and the switch signal SWb is held at "H", and the switch 30 is closed to the a side and the switch 31 is closed to the b side.

From this, the output signal of the counter 28 passes through the switch 3o and becomes the servo reference signal S8 in the servo control circuit 10a (
The output signal of the counter 29 passes through a switch 31 and is supplied as a servo reference signal S to the servo control circuit 10b (FIG. 1).

At this time, the frequency division ratio of the counter 29 is changing depending on the difference detection signal A, and therefore the servo reference signal Sb changes to perform fine timing adjustment.

When this fine timing adjustment is completed, the frequency division ratio of the counter 29 becomes equal to the frequency division ratio of the counter 28, and the servo reference signal S. , S, become equal in frequency and the magnetic tape 1
The traveling speeds of 3a and 13b (Fig. 1) become equal. However, in general, the phases of the servo reference signals SaSb do not match, and for this reason, the magnetic tapes 13a and 13b
The vertical synchronization signals of the reproduced video signals do not match in phase.

At the same time, a coincidence signal A of "H" is sent from the phase comparator circuit 4.
is supplied, and at its rising edge, the switch signal SWb is inverted from "H" to "L" and the switch 31 is switched to the a side. For this reason, the servo reference signals S- and Sb are output from the same counter 26, and have the same frequency and phase. Here, the servo control circuit 1 in FIG.
0a. 10b has the same configuration and the same characteristics,
As a result, the reproduced vertical period signals of the respective VTRs whose phases are set in the same phase relationship with the servo reference signals S- and Sb, respectively, match in phase with each other.

Therefore, in this specific example, frame alignment including phase matching of the vertical synchronizing signals is possible without providing a separate means for matching the phases of the vertical synchronizing signals as in the specific example shown in FIG. .

When the next offset value is then set in the phase comparison circuits 4 and 5 for insert editing, the match signal B falls, and at that edge, the switch signal SW
A becomes "H" and the switch 30 is switched to the b side. As a result, the servo reference signal sIl is output from the counter 29, and the next fine timing adjustment is
By controlling the frequency division ratio of the counter 29 using the difference detection signal A and changing the frequency of the servo reference signal S8, this is carried out in the VTR on the side labeled a in FIG. Then, when the coincidence signal B is supplied thereafter, the switch 3o is switched to the a side, and the servo reference signal S1 is outputted from the counter 28 in the same way as the servo reference signal S.

In this way, each period when the match signal B is not supplied, the switch 30. 31 is alternately closed to the b side, and the frequency of the servo reference signal S+Sb is alternately changed accordingly, so that fine timing adjustment is performed alternately between the two VTRs.

When editing, the state of the TFF 33 is preset depending on which of the two VTRs shown in FIG. 1 is to be used as the reference VTR first.

Although not shown in this specific example, a circuit for phase comparing the vertical synchronization signals of the video signals output from the signal processing circuits 6a and 6b in FIG. 1 is also provided, and the output signal is used as the coincidence signal D. A match indicator 16 (FIG. 1) is provided.

FIG. 6 is a block diagram showing still another specific example of the reference signal circuit 14 in FIG. 1, and parts corresponding to those in FIG. 2 are given the same reference numerals.

This specific example is a simplified version of the specific example shown in FIG.

That is, in FIG. G, the counter I8 has a constant frequency division ratio, and therefore the first
Servo reference signal S. of the frequency that puts the VTR on the side marked with the symbol a in the figure into normal playback mode. is always output. Further, the phase comparator Fi23 outputs a difference detection signal C representing the phase lead or lag of the vertical synchronizing signal VS2 from the vertical synchronizing signal device 22 with respect to the vertical synchronizing signal VS1 from the vertical synchronizing signal detector 21. As a result, in this specific example, the second
The switch 25 and the switch signal generator 26 in the illustrated example are omitted, and the difference detection signal A or C selected by the switch 24 is supplied only to the counter 20.

According to this specific example, in FIG. 1, the VTR on the side marked with the symbol a always serves as the reference VTR, and the running speed of the magnetic tape 13b is increased or decreased in the VTR on the side marked with the symbol b, thereby adjusting the timing finely. And the phase of the vertical synchronization signal is adjusted. Of course, in this case, rough timing adjustment is also performed by fast forwarding and rewinding the magnetic tape 13b.

As described above, in this specific example, the reference VTR is
Since it is set to TR, insert editing is not possible, but it is possible to perform synthesis, function as a noise reducer, and perform assembly editing in which one desired scene on the magnetic tape 13b is spliced and played back to one desired scene on the magnetic tape 13a. It is.

FIG. 7 is a block diagram showing still another specific example of the reference signal circuit 14 in FIG. 1, and parts corresponding to those in FIG. 4 are given the same reference numerals.

This specific example is a simplified version of the specific example shown in FIG.

That is, in FIG. 7, the counter 28 has a constant frequency division ratio, and therefore, from this counter 28, the first
Servo reference signal S. of the frequency that puts the VTR on the side marked with the symbol a in the figure into normal playback mode. is always output. As a result, in this specific example, the switch 30 and the switch signal generator 32 in the specific example shown in FIG. 4 are omitted, and the switch 31 is directly controlled by the coincidence signal B from the phase comparator circuit 4 (FIG. 1). be done. The switch 31 is closed during the period a of the coincidence signal B, and closed on the b side during other periods.

In this specific example as well, the reference VTR is determined to be a specific VTR, but the phase alignment of the vertical synchronizing signal is performed in the same way as in the specific example shown in FIG. 4, and the same as in the specific example shown in FIG. You can compose and edit the images.

Also, similar to the specific example shown in FIG. 4, the coincidence indicator 16 (
Needless to say, the apparatus also includes means for generating a coincidence signal D, which is supplied to the apparatus shown in FIG.

FIG. 8 is a block diagram showing a specific example of the phase comparator circuit 4 in FIG. There is.

In the figure, first, the difference N0 between the address values of the time codes at the above-mentioned predetermined positions in the desired scene on the magnetic tapes 13a and 13b is set in the arithmetic unit 38 as an offset value. This offset value NOf may always be the difference between the address value of the other magnetic tape 13b using the address value of one magnetic tape 13a as a reference, but it may also be the difference between the address value of the magnetic tape on the reference VTR side as a reference. It may also be the difference between the address values on the magnetic tape on the other VTR side. In any case, this offset value NOf will take a positive or negative value.

Now, if the address value of the time code reproduced from the magnetic tape 13a is Nml, and the address value of the time code reproduced from the magnetic tape 13b is N5, then in the phase comparator circuit 4, for example, An offset value N6f is added to the reproduction time code from the magnetic tape 13a by a computing unit 38, and the result is supplied to a comparator 39. Also, the time code reproduced from the magnetic tape 13b separated by the time code circuit 3 is directly transmitted to the comparator 3.
9.

The comparator 39 starts operating under the control of the system controller 15 upon completion of the rough timing adjustment, and compares the address value (Nll+Nof) to which the offset value N6f of one time code is added and the offset value of the other time code. Nb is compared, and when the two do not match, a difference detection signal A is output, and when the two match, a match signal B is output.
Output.

Note that the offset value N. Alternatively, f may be added to the time code reproduced from the magnetic tape 13b. However, in this case, the offset value Nof is different from the above case. becomes negative and reverse.

FIG. 9 is a prosock diagram showing a specific example of TBCI in FIG. 1, with 40a. 40b is a memory circuit, 41
a, 4lb are horizontal synchronization detectors, 42a, 42b
1 is a multiplier circuit, 43 is a continuation circuit, and parts corresponding to those in FIG. 1 are given the same reference numerals.

5. In the same figure, the video signal from the signal processing circuit 6a is supplied to a horizontal synchronization detector 41a to detect a horizontal synchronization signal, and a clock is generated from this horizontal synchronization signal in a multiplier path 42a. The memory circuit 40a has a capacity capable of storing several periods of horizontal scanning lines, and writes the video signal from the signal processing circuit 6a in units of one horizontal scanning line using the above-mentioned clock with the above-mentioned horizontal synchronization signal as a reference.

Similarly, for the video signal from the signal processing circuit 6b, using the horizontal synchronization detector 4lb and the multiplier circuit 42b,
Writing to the memory circuit 40b is performed in the same manner as above.

The continuation circuit 43 includes memory circuits 40a. 40b is simultaneously read and controlled.

Therefore, when the video signals reproduced from the two VTRs in FIG. 1 pass through this TBCI, the respective VT
Offsets, jitters, etc. of the phase control system occurring in R are absorbed, and the horizontal synchronizing signals also match each other. If the contents of these video signals are the same, the information contents of these video signals output from this TBC at the same time (in units of read clocks) are the same, and for this reason, the synthesizer 2 (first (Figure), the noise is reduced and the function as a noise reducer is obtained.

In this specific example, when editing, the two VTs in Figure 1
Even if the reference VTR is changed between R, the phase of the horizontal synchronizing signal is also the same between the two video signals at the scene switching point.

FIG. 10 is a block diagram showing another specific example of the TBCI in FIG.
9 is a vertical synchronization detector, 45 is a delay element, and parts corresponding to those in FIG. 9 are given the same reference numerals.

In this specific example, as in the case of using the reference signal circuit 14 shown in FIG. 6 or 7, one VTR in FIG.
This is used when R is always used as a reference VTR.

In FIG. 10, a vertical synchronization detector 44b and a horizontal synchronization detector 4lb detect a vertical synchronization signal and a horizontal synchronization signal, respectively, from the video signal from the signal processing circuit 6b. Then, the storage circuit 40 is initialized using this vertical synchronization signal as a reference point for one field, and the video signal from the signal processing circuit 6b is transferred to the storage circuit 40 in units of one horizontal scanning line using the horizontal synchronization signal as a reference point.
Write to 0. The write clock at this time is the horizontal synchronization signal detected by the horizontal synchronization detector 4lb, which is used by the multiplier circuit 4.
2b is used.

Further, the video signal from the signal processing circuit 6a is sent to the delay element 45.
The signal is delayed by several periods of the horizontal synchronizing signal and output from TBC1. On the other hand, the vertical synchronization detector 44a and the horizontal synchronization detector 41a detect a vertical synchronization signal and a horizontal synchronization signal from this video signal. Then, reading of the memory circuit 40 is initialized by this vertical synchronizing signal, and the video signal written in units of one horizontal scanning line as described above is read out based on the horizontal synchronizing signal. The reading clock at this time is the horizontal synchronization signal detected by the horizontal synchronization detector 41a, which is multiplied by the multiplier circuit 42a.
Use the value multiplied by . Here, the multiplier circuit 42a,
The multiplication ratios of 42b are equal.

Therefore, this video signal is written into the storage circuit 40 for one horizontal scanning period based on the horizontal synchronization signal of the video signal from the signal processing circuit 6b, and read out based on the horizontal synchronization signal of the video signal from the delay element 45. , the delay element 45
The video signal from the storage circuit 40 and the video signal from the storage circuit 40 have horizontal synchronization signals in phase. Also, by writing this video signal using a clock that is a multiplication of the horizontal synchronization signal of the video signal from the signal processing circuit 6b, and reading it using a clock that is a multiplication of the horizontal synchronization signal of the video signal from the delay element 45, the signal processing circuit 6a, When the video content of the video signal from 6b is the same, the information content of the video signal from delay element 45 and the video signal from storage circuit 40 match in clock units.

The vertical synchronization signals of the video signal from the signal processing circuit 6a and the video signal from the signal processing circuit 6b are matched by the system. Therefore, the amount by which the time axis of the video signal from the signal processing circuit 6b is corrected by the TBC 1 is the phase control offset and jitter that occur during reproduction of the two VTRs in FIG. 1. Therefore, the capacitance of the delay element 45 and the memory circuit 40 may be sufficient to correct this, that is, the capacity of several horizontal scanning lines.

Further, in this specific example, a vertical synchronization signal is used to initialize writing and reading of the memory circuit 40, but the signal processing circuit 6a
, 6b are already synchronized, so by matching the delay amount of the delay element 45 with the delay amount of writing and reading of the memory circuit 40, initialization using the vertical synchronization signal is not necessary. .

FIG. 11 is a block diagram showing another embodiment of the magnetic recording and reproducing system according to the present invention, in which 46a, 46b, 4
7a and 47b are magnets, and 48a and 48b are head position detectors, and parts corresponding to those in FIG. 1 are given the same reference numerals and redundant explanations will be omitted.

In the embodiment shown in FIG. 1, the phases of the vertical synchronization signals of the reproduced video signals from the two VTRs were directly aligned using these vertical synchronization signals, but in FIG. This is used to align the phase of the vertical synchronization signal.

In FIG. 11, two magnets 46a and 47a are provided on the rotating shaft of a cylinder motor 9a, and are rotated by the cylinder motor 9a in a predetermined phase relationship with respect to the rotating video head 7a+8a. These magnets 46
a. 47a is alternately detected by a head position detector 48a, and a 30 Hz head switching signal HSWa synchronized with the rotation of the rotating video heads 7a, 8a is generated. This head switching signal HSWa is, on the one hand, supplied to the signal processing circuit 6a, which switches the rotating video heads 7a, 8a and splices the reproduced video signals from now on to form a continuous video signal, and on the other hand, is supplied to the reference signal circuit 14. Supplied.

Further, two magnets 46b and 47b are also provided on the rotating shaft of the cylinder motor 9b, and the cylinder motor 9b
Accordingly, the video heads 7b and 8b rotate in a predetermined phase relationship with respect to the rotating video heads 7b and 8b. These magnets 46b, 47b
are alternately detected by the head position detector 48b, and a 30 Hz head switching signal HSWb synchronized with the rotation of the rotating video heads 7b, 8b is generated. On the one hand, this head switching signal HSWb is supplied to the signal processing circuit 6b, which switches the rotating video heads -5 6-=7b, 8b and splices the reproduced video signals from now on to make a continuous video signal, and on the other hand, The signal is supplied to the reference signal circuit 14.

Note that the switching point of the rotating video head by the head switching signals H S Wa and H S Wb is set within the vertical blanking period of the video signal. For example, in the VHS standard, the switching point of the rotating video head is set 6.5H before the leading edge of the vertical synchronizing signal. has been done.

The reference signal circuit 14 is similar to the embodiment shown in FIG. 1, except that when the time code address values match, the head switching signal H S Wa. The phase of the vertical synchronization signal is adjusted by comparing the phases of H S Wb. Therefore, the coincidence signal D is obtained by this phase comparison.

The other parts are similar to the embodiment shown in FIG. 1, and the same effects as this embodiment can be obtained.

FIG. 12 is a block diagram showing still another embodiment of the magnetic recording and reproducing system according to the present invention, and parts corresponding to those in FIG. 1 are given the same reference numerals and redundant explanation will be omitted.

In the figure, a signal processing circuit 6a, a rotating video head 7
a, 7b, cylinder motor 9a, servo control circuit 10a
, the capstan motor lla is one of the VTRs having a conventional configuration, and the servo control circuit 10a also includes a generator for generating a reference signal serving as a servo phase reference. The other parts are built into the other VTR, and this VTR
A VTR having a conventional configuration is connected to. However, the time code and CTLP index are already recorded on the magnetic tape 13a as well as on the magnetic tape 13b.

The comparison circuit 5 is set with the address value of the CTLP index at the start of the desired scene Q recorded on the magnetic tape 13b, and the comparison circuit 4 is set with the address value of the CTLP index at the start of the desired scene P recorded on the magnetic tape 13a. The difference between the address value of the time code at the start of the desired scene Q with respect to the time code is set as an offset value.

Then, the system controller 15 searches the desired scene on the magnetic tape 13a using a conventional method, and performs fast forwarding and rewinding on the magnetic tape 13b. As a result, the CTLP detector 12b reproduces the CTLP from the magnetic tape 13b, and the comparison circuit 5 compares the address value of the CTLP index extracted from this CTLP with a preset address value, and when the two match, The system controller 15 controls the servo control circuit 10b to stop the magnetic tape 13b.

This completes the cueing of the desired scene Q on the magnetic tape 13b.

Next, the system controller 15 controls the servo system 1 wholesale circuit 1
Operate VTRs 0a and 10b to put the two VTRs into normal playback mode. The subsequent steps are the same as in the previous embodiment, and the comparison circuit 4 compares the address values of the time codes reproduced from the magnetic tapes 13a and 13b.

The reference signal circuit 14 is controlled based on the comparison result,
By changing the frequency of the reference signal S, the running speed of the magnetic tape 13b is increased or decreased to perform fine (ie, frame-by-frame) timing adjustment.

In the manner described above, composition for split-screen display, noise reduction, etc. can be performed.

In this embodiment, a counter is used instead of the comparison circuit 50, and the current CTLP detector 1 on the magnetic tape 13b is
The magnetic tape 13b is fast forwarded or rewound so that the difference between the address value of the CTLP index reproduced by the CTLP index 2b and the address value of the CTLP index at the beginning of the desired scene is counted, and the desired scene of the magnetic tape 13b is located. You may also do so.

FIG. 13 is a block diagram showing still another embodiment of the magnetic recording and reproducing system according to the present invention, in which 49 is an input terminal, 50 is a vertical synchronization detector, 51 is a switch circuit, 52 is a supply reel, and 53 is a winding Take reel, 54. 55 is a rotation detector, 56 is a tape remaining amount detector, and parts corresponding to those in FIG. 1 are given the same reference numerals.

In this embodiment, scenes can be continuously recorded and played back over two magnetic tapes.

In the figure, first, the recording mode will be explained.

Although there is a recording command, the system controller 15 puts the signal processing circuits 6a and 6b and the servo control circuit 10a into an operating state. Video signal S ifi input from input terminal 49
is supplied to the signal processing circuits 6a, 6b and also to the vertical synchronization detector 50, where the vertical synchronization signal VS is separated. This vertical synchronizing signal VS is supplied to the servo control circuit 10a as a reference signal, and thereby the vertical synchronizing signal V
The VTR on the side marked with the symbol a is set to the recording mode with S as the phase reference. At this time, the vertical synchronizing signal vS is also supplied to the servo control circuit 10b, but since this servo control circuit 10b is in an inactive state, the VTR on the side marked with the symbol b is stopped.

Further, the vertical synchronization signal VS is also supplied to the time code circuit 3. This time code circuit 3 also has a time code generation function, and is synchronized with the supplied vertical synchronizing signal VS, and outputs the input video signal S+. A time code having a different address value by 1 is generated every n frames (or fields) and is supplied to the signal processing circuits 6a and 6b. In the signal processing circuits 6a and 6b, a time code is added to the input video signal during its vertical blanking period, and predetermined processing such as modulation for recording is performed. The video signal processed by the signal processing circuit 6a is supplied to rotary video heads 7a and 8a rotated by a cylinder motor 9a, and is sent to the magnetic tape 13a.
recorded above.

Here, in the VTR on the side marked with the symbol a, the rotation detector 54. 55 detects the rotational speeds of the supply reel 52 and take-up reel 53, and based on these rotational speeds, a remaining tape amount detector 56 detects the remaining amount of the magnetic tape 13a on the supply reel 52.

The system controller 15 monitors this detected remaining amount, and when this remaining amount reaches a small predetermined amount, it starts operating the servo control circuit 10b using the vertical synchronization signal VS from the vertical synchronization detector 50 as a reference signal. , set the VTR on the side marked with the symbol b to the recording mode. This results in
The video signal processed by the signal processing circuit 6b is supplied to rotating video heads 7b and 8b rotated by a cylinder motor 9b and recorded on a magnetic tape 13b. At this time,
The video signals recorded by the rotating video heads 7b and 8b are also added with time codes having the same content as the video signals recorded by the rotating video heads 7a and 8a.

When a predetermined period of time has elapsed after the start of recording in the VTR labeled b, the system controller 15 puts the servo control circuit 10a into a non-operating state and stops the VTR labeled a. Therefore, from now on,
The input video signal S i on the side of the VTR marked with the symbol b
Recording of Il is performed.

In this way, it becomes possible to record the scene continuously using the magnetic tapes 13a and 13b.

Next, the reproduction mode will be explained.

When there is a reproduction command, the system controller 15 puts the signal processing circuits 6a, 6b and the servo control circuit 10a into an operating state. The servo control circuit 10a is supplied with a reference signal from the reference signal circuit 14, and uses this as a phase reference to set the VTR on the side marked with the symbol a to a reproduction mode. Rotating video head 7a. The video signal reproduced from the magnetic tape 13a by 8a is supplied to the signal processing circuit 6a, where it becomes a continuous video signal, undergoes predetermined reproduction processing such as demodulation, and is supplied to the Yuni code circuit 3 and the switch circuit 51. be done. The switch circuit 51 includes a signal processing circuit 6a,
6b is supplied, but the initial setting is such that the signal processing circuit 6a side is selected, so that the video signal from the signal processing circuit 6a passes through the switch circuit 51 and becomes the output video signal S. It becomes ut.

Even in the playback mode, the system controller 15 monitors the remaining amount of the magnetic tape 13a on the supply reel 52 detected by the remaining tape amount detector 56, and when this remaining amount reaches the predetermined amount, the servo control circuit 10b. The servo control circuit lob is supplied with the reference signal Sb from the reference signal circuit 14, and uses this as a phase reference to set the VTR on the side labeled b to the reproduction mode. The video signal reproduced from the magnetic tape 13b by the rotating video heads 7b, 8b is supplied to the signal processing circuit 6b, where it becomes a continuous video signal, undergoes predetermined reproduction processing such as demodulation, and is sent to the time code circuit 3 and the switch circuit. 51. However, at this time, the switch circuit 51 is outputting the video signal from the signal processing circuit 6a.

The time code circuit 3 performs time code extraction operation by the system controller 15, and the signal processing circuit 6a,
The time code is extracted from the video signal from 6b. The address values of these time codes are compared by a comparator circuit 4. Among these video signals, the information contents of frames (or fields) assigned the same address value are exactly the same. Therefore, the magnetic tape 13a is
Proceeding to step b, if there is a delay, the address values of the two time codes compared by the comparison circuit 4 do not match. At this time, as in each of the previous embodiments, the comparison circuit 4 outputs the difference detection signal A.
The reference signal circuit 14 thereby outputs the reference signal S
By changing that frequency, the running speed of the magnetic tape 13b is increased or decreased.

When the address values of the two time codes match, the comparator circuit 4 generates a match signal B instead of the difference detection signal A. As a result, the reference signal circuit 14 uses the vertical synchronization signals of the video signals from the signal processing circuits 6a and 6b to generate the reference signal Sb.
The frequency and phase of the reference signal S. The phase of the vertical synchronization signal is adjusted. At the same time, the switch circuit 51 is controlled by the coincidence signal B, and after a certain period of time sufficient to complete the phase alignment of the vertical synchronization signal after the coincidence signal B is supplied, the signal processing circuit 6a processes the signal. The selection is switched to circuit 6b. As a result, the video signal from the signal processing circuit 6b passes through the switch circuit 51 and becomes the output video signal S out.

During the period from when the VTR on the side marked with the symbol b is set to the playback mode until the switch circuit 51 is switched, the remaining tape amount detector 56 detects the predetermined amount of remaining tape during recording. VT on the side marked with the symbol a after
This is set within the period for reproducing the portion recorded on the magnetic tape 13a before R is stopped, and when this portion is reproduced, the servo control circuit 10a is placed in a non-operating state by the system controller 15. , code a
The VTR on the side to which the mark is attached will stop. After this, reproduction from the magnetic tape 13b continues.

As described above, at the time when switching is performed by the switch circuit 51, the timing and vertical synchronization signals of the video signals from the signal processing circuits 6a and 6b are matched frame by frame, and therefore, at this switching point, image disturbances and There is no unnatural transition between images.

Note that in this embodiment, the switch circuit 51
It was assumed that the switching operation would be performed after a certain period of time after the signal was supplied, but the phase comparison of the vertical synchronizing signal or the phase comparison of the reference signals Sa and S, and the head switching signals of the respective VTRs was carried out to obtain a matching signal. The switch circuit 51 may perform the switching when the phases of the two signals coincide with each other in the phase comparison described above after the signal B is supplied.

Further, a signal processing circuit 6a+ is provided before the switch circuit 51.
TBC that adjusts the phase of the horizontal synchronization signal of the 6b video signal
may be provided. As the reference signal circuit 14, the circuit described above may be used.

In the embodiment described above, there are two VTRs, but
Needless to say, the same applies to three or more VTRs.

FIG. 14 is a block diagram showing an embodiment of the magnetic recording and reproducing apparatus according to the present invention, in which 4' is a comparison circuit, 6 is a signal processing circuit, 7 and 8 are rotary video heads, 9 is a cylinder motor, and 10 is a Servo system 1 wholesale circuit, 1l is capstan motor, 12 is CTLP detector, 13 is magnetic tape, 14'
is a reference signal circuit, 57 is an input terminal, 58.59 is a vertical synchronization detector, 60 is a phase comparator, 61 is a switch, 62 is a counter, 63 is a comparator, 64 is a reproduction VTR,
Parts corresponding to those in FIG. 1 are given the same reference numerals.

In the figure, the part to the right of the dashed-dotted line is the magnetic recording and reproducing device of this embodiment, and the reproducing VTR 64 is a conventional VTR, but a time code is added to each frame (or each field). A reproduced video signal Sv is output. In this embodiment, the reproduction video signal Sv is used as a reference, and rough timing is set so that the reproduction video signal Sv' from the magnetic tape 13 matches the timing in units of frames (or fields) and the vertical synchronization signal coincides with the reproduction video signal Sv. Coordination and detailed timing adjustments are made.

Signal processing circuit 6, rotating video heads 7, 8, cylinder motor 9, servo control circuit 10, capstan motor 11
, CTLP detector 12 and magnetic tape 13 are the same as those in the reproducing VTR denoted by reference numeral b in FIG.

The comparator circuit 4' is similar to the comparator circuit 4 in FIG.
Video signal Sv. The time codes of Sv' are compared and a difference detection signal A and a coincidence signal B are output, but the difference between these time codes (naturally corrected with an offset value)
It also outputs a difference value signal E representing .

The reference signal generation circuit 14' includes a frequency divider with a variable frequency division ratio and an oscillator, and generates a servo reference signal for the servo control circuit 10 by dividing the output signal of the oscillator by the frequency divider. The reference video signal Sv from the playback VTR 64 and the playback video signal 3, / from the signal processing circuit 6 and the vertical synchronization detector 58, respectively.
．． 59, the vertical synchronizing signal is detected, and the phases are compared by a phase comparator 60.

The difference detection signal C output from the phase comparator 60 and the difference detection signal A output from the comparison circuit 4' are selected by a switch 61 depending on the presence or absence of the coincidence signal B.

The frequency divider of the reference signal circuit 14' changes its frequency division ratio in accordance with the difference detection signal selected by the switch 61, and the frequency of the servo reference signal of the servo control circuit 10 increases or decreases.

When the reproduction VTR 64 is set to the reproduction mode and the servo control circuit 10 is operated in the reproduction mode by the servo reference signal from the reference signal circuit 14' by the system controller 15, the video signal Sv. The time codes of Sv are compared by a comparison circuit 4', and a difference value signal E representing the difference between them is output. This difference value signal E is supplied to the comparator 63 and the system controller 15.

The system controller 15 takes in the supplied difference value signal E, determines whether the time code difference is larger than a predetermined dark value, and if it is larger, the difference value of this difference value signal E is determined. The comparator 63 is preset and the counter 62 is reset, and the servo control circuit 10 is forcibly controlled to run the magnetic tape 13 at high speed in the forward or reverse direction.

On the other hand, the CTLP detector 12 detects the CTL from the magnetic tape 13.
The counter 62 counts this CTLP. The count value of the counter 62 is compared with a preset value (previous difference value) by a comparator 63, and if the two match, the counter 62 sends a match signal to the system controller 15. Upon receiving this match signal, the system controller 15 takes in the difference value signal from the comparator circuit 4' again and determines whether the difference value is larger than the predetermined threshold value. If it is larger, the difference value of the difference value signal E is preset in the comparator 63, the counter 62 is reset, and the above operation is performed again.

Although this operation performs rough timing adjustment, this operation will be explained in more detail using a numerical example.

Modes for running magnetic tape at high speed include fast forward,
There is a rewind mode and a search mode.

The fast forward and rewind modes run at extremely high speeds in the unloading state, and in this case it is impossible to stop the magnetic tape instantaneously, and the tape position shifts by about 20 frames due to loading. That is inevitable. For this reason, the tape position setting accuracy during fast forwarding and rewinding is ±100 frames or more.

Further, in the search mode, the magnetic tape is run at high speed in the loading state, but the running speed is set slower than in the fast forward and rewind modes. For this reason, although the tape position setting accuracy in the search mode is higher than in the fast forward and rewind modes, an error of ±5 frames or more still occurs.

Therefore, in this case, the system controller 15 sets the above-mentioned predetermined darkness value to ±5 frames.

Then, the difference value of the time code is ±1 by the difference value signal E.
00 frames or more, the servo control circuit 10
is controlled to set the fast forward or rewind mode, and when the difference value is between ±5 frames and ±100 frames, the search mode is set. Therefore, even if the fast forward or rewind mode is initially set, if the difference value becomes more than ±5 frames and less than ±100 frames by subsequently capturing the difference value signal E, the search mode is set 71. That will happen.

The time code difference value is below the specified dark value (in the above case, ±
5 frames or less), the system controller 15 controls the servo control circuit 10 to operate with the servo reference signal from the reference signal circuit 14'/. Thereby, as described above, when the comparison circuit 4' does not output the match signal B, the reference signal circuit 14' is controlled by the difference detection signal A, and fine timing adjustment is performed. When the matching signal B is output from the comparison circuit 4', the reference signal circuit 14' is controlled by the difference detection signal C from the phase comparator 60, and the vertical synchronization signals of the video signals sv and sv' are aligned in phase. .

Portions other than those described above are the same as those in the embodiment shown in FIG. 1, so explanations will be omitted.

FIG. 15 is a block diagram showing another embodiment of the magnetic recording/reproducing apparatus according to the present invention, in which 65 is a CTLP index circuit, 66 is an input terminal, and parts corresponding to those in FIG. 14 are given the same reference numerals. Repeated explanations will be omitted.

? The embodiment shown in Fig. 14 compares the time code difference value and the playback CTLP count value in rough timing adjustment, but the embodiment shown in Fig. 15 compares the CTLP index. This is what I did.

In FIG. 15, the reproducing VTR 64 reproduces and outputs not only the video signal to which the time code has been added, but also the CTLP index from the magnetic tape. Playback VTR6
The CTLP index IN outputted from the input terminal 4 is inputted from the input terminal 66 and supplied to the comparator 63. Also, C
The CTLP reproduced from the magnetic tape 13 by the TLP detector 12 is supplied to the CTLP index 65, and the CTLP is
TLP index IN' is extracted and supplied to comparator 63. The comparator 63 is CTLP index IN,
The value of IN' is corrected and compared with the offset value, and when the two match, a match signal is sent to the system controller 15.

In the system controller 15, a predetermined dark value is set, and the difference value signal E from the comparator circuit 4' is taken in to determine whether the difference value between the time codes of the video signals Sv and Sv' is larger than this dark value. Determine whether

If this is large, the system controller 15 controls the servo control circuit 10 to cause the magnetic tape 13 to run at high speed in the forward or reverse direction.

Here, as explained above, even if the values of CTLPININ' match, the difference value of the time code is a value of about ± several hundred frames. For this reason, the darkness value in this case is set to several hundred frames. If the time code difference value is less than this dark value, CTLP index I
The values of N and IN' match.

When the magnetic tape 13 is running at high speed as described above, when the values of the CTLP indexes IN and IN' match and a match signal is output from the comparator 63, the system controller 15 determines that the rough timing adjustment has been completed. As such, the servo control circuit 10 is operated by the servo reference signal outputted from the reference signal circuit 14, and fine timing adjustment and phase adjustment of the vertical synchronization signal are performed as in the embodiment shown in FIG.

Although numerical values are specifically shown in each of the above examples, these are only shown for convenience of explanation, and the present invention is not limited thereby.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to synchronize the timing of desired scenes played from multiple VTRs on a frame-by-frame basis, and it is possible to switch scenes in editing with high precision without excess or deficiency. In addition, split-screen display and synthesis as a noise reducer can be performed satisfactorily.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the magnetic recording/reproducing system according to the present invention, FIG. 2 is a block diagram showing a specific example of the reference signal circuit in FIG. 1, and FIG. 3 is an explanatory diagram of its operation. 4 is a block diagram showing another specific example of the reference signal circuit in FIG. 1, FIG. 5 is an explanatory diagram of its operation, and FIGS. 6 and 7 are further diagrams of the reference signal circuit shown in FIG. 1. A block diagram showing another specific example, FIG. 8 is a block diagram showing one specific example of the time code comparison circuit in FIG. 1, and FIGS. 9 and 10 are specific examples of the time base collector in FIG. 1. Block diagram showing Figures 11 to 1
FIG. 3 is a block diagram showing another embodiment of the magnetic recording/reproducing system according to the present invention, and FIGS. 14 and 15 are block diagrams showing embodiments of the magnetic recording/reproducing apparatus according to the present invention. ■...Time base collector, 2...Synthesizer, 3.
...Time code circuit, 4.4',5...Comparison circuit,
7, 7a, 7b, 8.8a, 8b...rotating video head, 10, 10a, 10b=servo control circuit, 1
2.12a, 12b - control signal detector, 1
3, 13a, 13b...magnetic tape, 14.14
'... Reference signal circuit, 15... System controller, 16... Coincidence indicator, 46a+ 46b+ 47
a+ 47b...7 gnets, 48a, 48b...
・Head position detector, 49...Video signal input terminal, 5
0... Vertical synchronization detector, 51... Switch circuit, 5
2... Supply reel, 53... Take-up reel, 54,5
5... Rotation detector, 56... Tape remaining amount detector, 5
8.59... Vertical synchronization detector, 60... Phase comparator, 61... Switch, 62... Counter, 63...
・Comparator, 64...VTR for playback165...CTL
P index circuit. Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] A magnetic tape on which a video signal to which a time code is added whose content changes sequentially every frame (or field) is recorded, and an index indicating the position is recorded on a control track. a plurality of magnetic recording and reproducing means for reproducing, and any one of the magnetic recording and reproducing means;
One is a reference magnetic recording/reproducing means, and another arbitrary one is a sub-magnetic recording/reproducing means, and the index is reproduced by the reference magnetic recording/reproducing means, and the slave magnetic recording/reproducing means is reproduced at the same timing. a first adjusting means for coarsely adjusting the running of the magnetic tape in the subordinate magnetic recording/reproducing means so that the index reproduced from the means has a desired relationship; and an adjusting operation of the first adjusting means. operation starts at the end of the reference magnetic recording/reproducing means, so that the time code reproduced by the reference magnetic recording/reproducing means and the time code reproduced from the subordinate magnetic recording/reproducing means at the same timing have a predetermined relationship. and a second adjusting means for finely adjusting the running of the magnetic tape in the subordinate magnetic recording and reproducing means, and the reference magnetic recording and reproducing means and the subordinate magnetic recording and reproducing means reproduce data at the same timing. 1. A magnetic recording and reproducing system characterized in that the running phase relationship of each magnetic tape can be set so that the time codes are in the desired relationship. 2. A plurality of magnetic heads equipped with servo control means for phase control of magnetic tapes and rotating video heads, and that reproduces video signals from magnetic tapes to which time codes whose contents change sequentially for each frame (or field) are added. Any one of the recording and reproducing means and the magnetic recording and reproducing means is a reference magnetic recording and reproducing means, and the other arbitrary one is a subordinate magnetic recording and reproducing means, and the reference magnetic recording and reproducing means and the subordinate magnetic recording and reproducing means are used. a time code comparison means for comparing the contents of the time code reproduced from the reference and outputting a difference detection signal when the two do not have the desired relationship, and outputting a matching signal when the two have the desired relationship; A reference signal serving as a phase reference is supplied to the servo control means of the magnetic recording and reproducing means and the subordinate magnetic recording and reproducing means respectively, and the difference detection signal from the time code comparing means is used to control the servo control means of the subordinate magnetic recording and reproducing means. As the frequency of the reference signal is increased or decreased and the matching signal is supplied from the time code comparing means, a phase shift of the vertical synchronization signal of the reproduced video signal by the reference magnetic recording/reproducing means and the subordinate magnetic recording/reproducing means. a reference signal circuit that changes the phase of a reference signal to the subordinate magnetic recording/reproducing means according to the frame (or What is claimed is: 1. A magnetic recording and reproducing system characterized in that it is configured to enable timing alignment in field units and phase alignment of vertical synchronization signals. 3. In claim 2, the reference signal circuit includes an oscillator and a frequency-divided output signal of the oscillator so that one of the reference signals of the reference magnetic recording and reproducing means and the other of the reference signals of the slave magnetic recording and reproducing means are divided. two frequency dividers that generate a reference signal, and a vertical synchronization signal reproduced by the subordinate magnetic recording and reproducing means (or a phase comparator that detects a phase shift between this signal and a signal with a constant phase relationship;
Of the two frequency dividers, the frequency division ratio of the frequency divider that generates a reference signal to the slave magnetic recording/reproducing means is determined by the difference detection signal from the time code comparison means and the detection output signal of the phase comparator. 1. A magnetic recording and reproducing system comprising: means for selectively changing the magnetic recording and reproducing system. 4. In claim 2 or 3, the frame (or field) of the reproduced video signal is controlled by the reference signal circuit.
1. A magnetic recording and reproducing system comprising a coincidence indicator that indicates that unit timing alignment and vertical synchronization signal phase alignment have been achieved. 5. The magnetic device according to claim 4, wherein the reproduction video signals of the reference magnetic recording/reproducing means and the secondary magnetic recording/reproducing means can be synthesized during the display period of the coincidence indicator. Recording and playback system. 6. A plurality of magnetic heads equipped with servo control means for phase control of magnetic tapes and rotating video heads, and that reproduces video signals from magnetic tapes to which time codes whose contents change sequentially for each frame (or field) are added. a recording/reproducing means, and any one of the magnetic recording/reproducing means is a reference magnetic recording/reproducing means, and any other one is a subordinate magnetic recording/reproducing means; the reference magnetic recording/reproducing means and the subordinate magnetic recording means; a time code comparison means for comparing the contents of the time code reproduced from the reproduction means, outputting a difference detection signal when the two do not have the desired relationship, and outputting a coincidence signal when the two have the desired relationship; A reference signal serving as a phase reference is supplied to the servo control means of the reference magnetic recording and reproducing means and the slave magnetic recording and reproducing means, respectively, and the magnetic recording and reproducing of the slave is performed based on the difference detection signal from the time code comparing means. The frequency of the reference signal is increased or decreased to the means, and as the matching signal is supplied from the time code comparison means, the reference signal is sent to the subordinate magnetic recording and reproducing means. It consists of a reference signal circuit that makes the same frequency and phase as the signal, and a vertical synchronization signal and timing alignment of the reproduced video signal in frame (or field) units by the reference magnetic recording and reproducing means and the subordinate magnetic recording and reproducing means. What is claimed is: 1. A magnetic recording and reproducing system characterized in that the system is configured to enable phase matching of. 7. In claim 6, the reference signal circuit includes an oscillator, a first frequency divider that divides the output signal of the oscillator at a constant frequency division ratio, and a first frequency divider that divides the output signal of the oscillator and divides the frequency of the output signal of the oscillator. A second frequency divider whose frequency division ratio increases or decreases depending on the difference detection signal from the code comparing means, and an output signal of the first frequency divider is supplied as the reference signal to the reference magnetic recording/reproducing means. Further, the secondary magnetic recording/reproducing means receives the output signal of the second frequency divider during the period in which the time code comparing means does not output the coincidence signal, and also transmits the output signal of the second frequency divider during the period in which the time code comparing means outputs the coincidence signal. A magnetic recording and reproducing system comprising means for supplying the output signals of the first frequency dividers as the reference signals. 8. In claim 6 or 7, the frame (or field) of the reproduced video signal is controlled by the reference signal circuit.
1. A magnetic recording and reproducing system comprising a coincidence indicator that indicates that unit timing alignment and vertical synchronization signal phase alignment have been achieved. 9. The magnetic device according to claim 8, wherein the reproduction video signals of the reference magnetic recording and reproducing means and the secondary magnetic recording and reproducing means can be synthesized during the display period of the coincidence indicator. Recording and playback system. 10. A magnetic recording and reproducing device that synchronizes the phase with a reference video signal from a desired video source to which a time code whose contents change sequentially for each frame (or field) is added, and that records information from a magnetic tape using a servo control circuit. 1 frame (
A magnetic recording/reproducing means for reproducing a video signal to which a time code whose content changes sequentially for each field) is used to compare the time code between the reproduced video signal and the reference video signal, and the difference between the time codes is determined by a predetermined difference. A first signal is generated when the time code difference is greater than the predetermined value, a second signal is generated when the time code difference is less than or equal to zero, and a third signal is generated when the time code difference is zero. code comparison means;
phase comparison means for comparing the phases of vertical synchronization signals of the reproduced video signal and the reference video signal; and a phase comparison means for controlling the servo control circuit in accordance with the output of the first signal of the time code comparison means, and controlling the magnetic tape. control means for causing the time code comparison means to run at high speed;
generates a reference signal whose frequency increases or decreases according to the output signal of the phase comparison means, and whose frequency increases or decreases according to the output signal of the phase comparison means as the third signal of the time code comparison means outputs; It consists of a reference signal circuit that serves as a phase reference signal for the servo control circuit, and is configured to enable timing alignment of the reproduced video signal to the reference video signal in units of frames (or fields) and phase alignment of the vertical synchronization signal. A magnetic recording/reproducing device characterized by: 11. In claim 10, a coincidence indicator is provided to indicate that timing alignment of the reproduced video signal and the reference video signal in units of frames (or fields) and phase alignment of the vertical synchronization signal have been achieved. A magnetic recording/reproducing device characterized by: 12. The magnetic recording and reproducing apparatus according to claim 11, wherein the reference video signal and the reproduced video signal can be synthesized during the display period of the coincidence indicator. 13. N magnetic recording/reproducing means of 1st, . . . , Nth (where N is an integer of 2 or more) and the contents of the input video signal change sequentially for each frame (or field). a means for adding a time code, and the i-th (however,
i=1, 2, 3, ..., N-1), the input video signal to which the time code has been added is
When the remaining amount of the tape reaches a predetermined amount, the (i+1)th magnetic recording/reproducing means records the input video signal on the (i+1)th magnetic tape to which the time code is added.
means for starting recording on the i-th magnetic tape and stopping the recording of the i-th magnetic recording/reproducing means after a predetermined period of time has elapsed; so that the input video signal can be recorded continuously, and the j-th (however, j=1, 2, 3, . . .
, N-1) reproduces the video signal to which the time code has been added from the i-th magnetic tape, and when the remaining tape amount reaches the predetermined amount, the (j+
1) Start reproducing the video signal to which the time code is added from the (i+1)th magnetic tape in the magnetic recording/reproducing means, and after the predetermined time elapses, start the jth magnetic recording/reproducing means. Compare the contents of the time code reproduced by the means for stopping and the j-th and (j+1)-th magnetic recording and reproducing means, and when the two do not match, output a difference detection signal, and when the two match. a time code comparing means for outputting a coincidence signal; a reference signal circuit for changing a reference signal serving as a servo phase reference of the (j+1)th magnetic recording/reproducing means according to the difference detection signal; and the time code comparing means. switch means for switching and outputting the reproduced video signal of the j-th magnetic recording/reproducing means to the reproduced video signal of the (j+1)-th magnetic recording/reproducing means within the predetermined time after outputting the coincidence signal; A magnetic recording/reproducing system characterized in that the first, second, .