JPH0773365B2 - Segment recording type video tape recorder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to one vertical scanning period consisting of various video signals such as band-compressed video signals for high-definition television (high-vision) broadcasting and baseband video signals. The present invention relates to a segment recording type video tape recorder device for recording / reproducing the video signal of (1) on a plurality of tracks of a magnetic tape by a helical scan of a plurality of rotating heads.

[Conventional technology]

Conventionally, for example, VHS, β type helical scan type home video tape recorders usually use 180
Magnetic tapes are alternately helically scanned by a pair of rotary heads for recording and reproduction provided at positions separated by ゜, and the video signal for each vertical scanning period of standard television broadcast is sequentially transferred to each track of the magnetic tape. It is configured to record and reproduce.

In order to allow a margin for timing change of head switching, the magnetic tape runs with an angle larger than 180 ° of the rotating cylinder, and the head on the trace end side and the head on the trace start side are overlapped during the overlapping period before and after the head switching. Simultaneously traces the magnetic tape.

By the way, a band-compressed video signal (hereinafter referred to as a high-definition television signal) of high-definition television (high-vision) broadcasting is recorded and reproduced by using a helical scan type video tape recorder such as the above-mentioned home-use video tape recorder. Is being considered.

When recording and reproducing a high-definition television signal, the signal band of the high-definition television signal is about 5 times the signal band of the video signal of standard television broadcasting. Therefore, the relative speed between the magnetic tape and the rotating head is changed. It is necessary to increase the recording density and to perform recording and reproduction at a higher density than the recording density of the video signal of standard television broadcasting.

Therefore, for example, technical report (VR70-
In 4) "Study of analog segment recording in home-use MUSE VTR", the rotating cylinder is rotated at high speed to increase the relative speed between the magnetic tape and the rotating head to widen the recording / reproducing signal band. It is described that a high-definition television signal for one vertical scanning period is divided into a plurality of tracks and recorded and reproduced.

In addition, the “FEED FORWARD CONTROL TIME BASE COLLECTOR” of the Technical Report of the Television Society of Japan (TEBS83-1) divides the video signal of one vertical scanning period of the high-definition TV broadcast baseband into a plurality of tracks. It is described that recording and reproducing are performed as follows. By the way, as described in both of the above technical reports, when a video signal in one vertical scanning period is divided into a plurality of tracks for recording and reproducing, a synchronizing signal of the reproduced signal is present at the track switching portion, that is, before and after the head switching point. A phase discontinuity occurs due to the deviation of the, and skew distortion occurs on the playback screen.

Further, the specifications of high-definition television broadcast signals are extremely strict with respect to time axis fluctuations (jitter), and it is necessary to suppress the time axis fluctuations during reproduction within the allowable range of the specifications.

Therefore, in the technical report (VR70-4), etc., a helical scan type video tape recorder unit (hereinafter referred to as a VTR unit) such as a home video tape recorder and a digital time base collector for correcting a time base error are described. With a segment recording type video tape recorder equipped with a section (hereinafter referred to as the TBC section), a method of cutting and shortening a portion of the high-definition television signal at the time of recording to form a non-signal section and preventing skew distortion , A method of correcting a time axis error (fluctuation) at the time of reproduction by adding a negative sync signal for time axis error correction and a burst signal to each 1-track recording signal,
It is described that a high-definition television signal is decomposed and recorded in a plurality of tracks and is reproduced.

An example of a conventional segment recording type video tape recorder for recording and reproducing a high-definition television signal, that is, a helical scan type VTR section and a feedforward TBC section are provided for one vertical scanning period. A segment recording type video tape recorder for recording and reproducing a high quality television signal by dividing it into two tracks is constructed as shown in FIG.

In Fig. 3, (1) is a helical scan type VTR section equipped with a pair of rotary heads (2A) and (2B) for recording and reproducing,
(3) is a common recording circuit provided in the VTR section (1), which is composed of an FM modulation circuit (4) and a recording amplifier (5), and is a video signal input from the TBC section described later at the time of recording, that is, a high signal. The quality television signal is FM-modulated and amplified, and then supplied to the heads (2A) and (2B). Reference numeral (6) is a common reproducing circuit provided in the VTR section (1).
Two reproduction amplifiers (8A) and (8B) for amplifying the reproduction signals of each one track of the magnetic tape (7) reproduced by A) and (2B), and both amplifiers (8A) and (8B) ) The output signal of the switch (9) and the output signal of the switch (9) are FM demodulated.
It consists of an FM demodulation circuit (10).

(11) is a feedforward type TBC section connected to the VTR section (1), which is a recording block for processing the high-definition television signal from the recording input terminal (12) and outputting it to the recording circuit (3). (13) and a reproduction processing block (15) for processing the output signal of the reproduction circuit (6) and outputting it to the reproduction output terminal (14)
It has and.

(16) is an A / D conversion circuit connected to the input terminal (12), (1
7) is a recording head blanking processing circuit connected to the conversion circuit (16), (18) is the first and second line memos (18a),
A recording memory circuit having (18b), a processing circuit (1
7) connected to. Reference numeral (19) is a synchronization / burst addition circuit connected to the memory circuit (19), and reference numeral (20) is a D / A conversion circuit provided between the addition circuit (19) and the modulation circuit (4).

(21) is an A / D conversion circuit connected to the demodulation circuit (10), (2
Reference numeral 2) is a reproduction memory circuit having first and second line memories (22a) and (22b), which is connected to the conversion circuit (21). (23) is a time axis error detection circuit connected to the conversion circuit (21), and (24) is a reproduction memory control circuit connected to the detection circuit (23), based on the detection signal of the detection circuit (23), Writing and reading of both memories (22a) and (22b) of the memory circuit (22) are controlled. (25) is a reproduction head blanking processing circuit connected to the memory circuit (22), and (26) is a D / provided between the processing circuit (25) and the output terminal (14).
It is an A conversion circuit.

Incidentally, in FIG. 3, two heads (2A) and (2B) are shown in the figure in order to show the recording and reproducing connections of the heads (2A) and (2B), respectively. Head (2
There is only one each of A) and (2B), and the connection can be switched between recording and playback.

The heads (2A) and (2B) are provided 180 ° apart from the rotary cylinder as in the conventional home video tape recorder, and the tape (7) is attached to the rotary cylinder.
Drive with an angle greater than 180 °.

Therefore, the heads (2A) and (2B) are the head switching point (2A) or (2B) on the trace end side and the head (2B) or (2A) on the trace start side during recording and playback. Simultaneously trace the tape (7) during the front and back polymerization periods.

Head (2A) and (2B) head switching during recording and playback is synchronized with the head (2A) and (2B) traces. This is performed by the segment switching timing signal shown in FIG.

Then, during recording, the high-definition television signal of FIG. 4 (b) input to the input terminal (12) is digitally converted by the conversion circuit (16) and then input to the processing circuit (17).

At this time, the processing circuit (17) performs a recording blanking process using a memory or the like to reduce a part of the input high-definition television signal in one vertical scanning period by shortening it and move the time axis to 1 Separate output for each track.

Furthermore, the output signal of the processing circuit (17) is the memory circuit (18).
Is input to the memory circuit (18) at this time.
A) and (18b) are controlled to write and read in reverse every 1H (1 horizontal scanning period), the input signal is time-compressed, and there is no signal period at the end of each 1 track, that is, a gap. To form.

Then, the negative horizontal synchronizing signal and the burst signal of the additional circuit (19) are inserted and added as a signal for time axis error correction into the gap of each track formed by the time compression of the memory circuit (18). To be done.

Further, the output signal of the additional circuit (19) is analog-converted by the conversion circuit (20), and the video signal of each track formed by analog conversion from the conversion circuit (20) to the modulation circuit (4). Are sequentially output.

Then, the video signal FM-modulated by the modulation circuit (4) is alternately supplied to the heads (2A) and (2B) via the amplifier (5), and recorded on the heads (2A) and (2B). First, a high-definition television signal for one vertical scanning period is divided and recorded on two consecutive tracks of the tape (7).

At this time, based on the recording blanking processing of the processing circuit (17), the high-definition television signal of FIG. 4 (b) is a signal in the overlapping period in the middle of each vertical scanning period, that is, the signal of the shaded portion (A). Are overlapped and recorded in each track as the signals in the shaded areas (A ₁ ) and (A ₂ ) in (c) and (d) of FIG. The signal of the portion (B) is scraped and disappears.

Note that FIG. 4 (c) shows the output signal of the processing unit (17) by analog conversion separately for the heads (2A) and (2B), and FIG. 4 (d) shows the heads (2A) and (2B). The signals recorded on the tape (7) are shown below.

On the other hand, at the time of reproduction, each track of the tape (7) is sequentially reproduced based on the reproduction traces of the heads (2A) and (2B), and the reproduction signals of the heads (2A) and (2B) are reproduced. ), (8B), and then synthesized by switching the switch (9) based on the segment switching timing signal.

Then, the reproduced signal synthesized by the switch (9) is FM demodulated by the demodulation circuit (10), and then the conversion circuit (21).
Are converted to digital.

By the way, the head switching of the switch (9) is performed during the overlapping period, and the signal output from the demodulation circuit (10) to the conversion circuit (21) becomes the same reproduction signal as the recording signal of FIG. 4 (d).

Furthermore, the output signal of the conversion circuit (21) is the memory circuit (22).
And the detection circuit (23).

Then, the detection circuit (23) detects a time-axis error (fluctuation) of the reproduction signal based on the negative horizontal synchronizing signal and the burst signal in the input reproduction signal, and detects, for example, the level of the detected error. The detection signal is output to the control circuit (24).

In addition, the control circuit (24) controls the memories (22a) and (22b) of the memory circuit (22) to write and read each other in reverse, and controls the high-definition television signal in the output signal of the conversion circuit (21). It is time-expanded and output from the memory circuit (22). At this time, based on the detection signal of the detection circuit (23), the memory (22
The write timing of a) and (22b) is variably controlled according to the time axis error, the time axis error of the output signal of the memory circuit (22) is corrected, and the read timing of the memories (22a) and (22b) is controlled. Based on the above, the signal added by the adding circuit (19) is removed.

The output signal of the memory circuit (22) is processed by the processing circuit (25).
At this time, the processing circuit (25) uses a memory or the like to perform reproduction blanking processing so that the signals in the overlapping portions of the two tracks overlap each other (2A) or (2A).
The entire reproduction signal of one track on the B) side is time-shifted and output to the conversion circuit (26).

Furthermore, the reproduced high-definition television signal is output from the output terminal (14) by analog conversion of the conversion circuit (26).

By the way, by the blanking process of the processing circuit (25),
The recording signal of FIG. 4 (d) is moved on the time axis as shown in FIG. 4 (e), and at this time, the shaded area (A ₁ ) in FIG. 4 (d),
The signal of (A ₂ ) is the shaded area (A ₁ ) ′ in FIG.
(A ₂ ) ′ signal, and the output terminal (14)
As shown in FIG. 6F, the shaded area (A) in FIG.
A high-definition television signal is output by reproducing the above signal as a hatched portion (A) ′ signal.

4 (e) shows the signals processed by the processing section (25) separately for the heads (2A) and (2B), and FIG. 4 (f) shows the output terminal (14) from the conversion circuit (26). ) Shows the signal output.

That is, in the apparatus of FIG. 3, at the time of recording, instead of cutting and shortening the signal in the shaded area (B) by the recording blanking process, the signal in the shaded area (A) is recorded by overlapping during the overlapping period. During playback, a high-definition television signal for each vertical scanning period is obtained without skew distortion, and playback is performed by correcting the time axis error during playback based on the negative horizontal sync signal and burst signal added during recording. The time axis error of the high-definition television signal for each vertical scanning period is corrected.

[Problems to be solved by the invention]

By the way, in the case of the apparatus of FIG. 3, in order to prevent skew distortion at the time of reproduction, a part of the high-definition television signal in one vertical scanning period at the time of recording, that is, the shaded area (B) of FIG. 4 (b).
Is required to be shortened by cutting off the portion, and in this case, the reproduced high-definition television signal lacks a portion corresponding to the shaded portion (B) as shown in the blank portion (C) of FIG. .

On the other hand, in the case of a high-definition television signal, as is clear from its transmission format, there is no period that can be lost, that is, an extra period that can be sacrificed.

Therefore, the above-mentioned shaded portion (B) is usually set in the audio information area during the vertical blanking period of the high-definition television signal, and in this case, recording and reproduction of audio information in the audio information area cannot be performed.

That is, in the case of the apparatus shown in FIG. 4, in order to prevent skew distortion during reproduction, a high-definition television signal in one vertical scanning period cannot be completely recorded, and some information such as audio information is lost. There is a problem.

As described above, all of the conventional segment recording type video tape recorders that record and reproduce high-definition television signals reduce and shorten a part of the high-definition television signal at the time of recording to reduce the skip time during reproduction. In order to prevent distortion, there are the same problems as described above.

In addition, the baseband video signal of high-definition television broadcasting, the band-compressed video signal used for other than high-definition television broadcasting, and the baseband video signal are divided into a plurality of tracks as described above, and recorded and reproduced. Also in this case, if a part of the video signal at the time of recording is cut and shortened in order to prevent skew distortion at the time of reproduction, the same problem as described above occurs.

Then, according to the present invention, it is a technical object to completely record a video signal in one vertical scanning period at the time of recording without omission and to obtain a complete video signal in one vertical scanning period without skew distortion at the time of reproduction. And

[Means for solving problems]

The present invention has been made with the above points in mind,
The head on the trace end side and the head on the trace start side are provided with a plurality of rotary heads for recording / reproducing that simultaneously trace the magnetic tape during the overlap period before and after the head switching point, and one vertical scan is performed by the recording / reproducing trace of each head. In a helical scan type segment recording video tape recorder device that records and plays back the video signal of the period by dividing it into multiple tracks of the magnetic tape, divides the video signal input at the time of recording into divided lengths. A recording memory circuit for time-compressing and outputting, an additional circuit for adding a signal for time axis error correction to a gap generated by the time compression of the recording memory circuit, and one vertical scanning period of one vertical scanning period output from the additional circuit. A common process of recording the video signal and supplying the video signal to the heads so that the same signal is recorded during the overlapping period of each track. A recording circuit; a plurality of reproducing circuits for reproducing the reproduced signals of the heads and outputting the reproduced signals separately; and a plurality of reproducing memory circuits for time-expanding and outputting the video signals of the output signals from the reproducing circuits. , A plurality of time axis error detection circuits for detecting time axis errors of the output signals from the respective reproduction circuits and a synchronization signal in the output signals from the respective reproduction circuits are compared, and between the reproduction signals from the respective heads. A sync deviation detecting unit for detecting a sync deviation, and a write timing of each reproduction memory circuit based on a detection signal of each time axis error detection circuit, and each reproduction memory based on the detection signal of the sync deviation detecting unit. The signal added by the additional circuit is removed from each reproduction memory circuit by adjusting the circuit write timing and controlling the read timing of each reproduction memory circuit. A plurality of memory control circuits for reading signals, and a signal synthesizing circuit for synthesizing the signals read from the respective reproducing memory circuits and continuously outputting the reproduced video signals for one vertical scanning period are provided. It is a segment recording type video tape recorder device.

[Work]

Therefore, the video signal of one vertical scanning period is divided and recorded into a plurality of tracks by a plurality of rotating heads that simultaneously trace the magnetic tape during the superposition period of the start and the end of the trace, and at the time of reproduction, reproduction of each head is performed. The signals are reproduced separately, and the reproduced signals of the heads after the reproduction processing are combined after the correction of the time axis error and the correction of the synchronization deviation between the tracks, and the combined signals are produced in one vertical scanning period. Therefore, skew distortion during playback is prevented, and 1
A complete video signal in the vertical scanning period is divided into a plurality of tracks and recorded and reproduced.

〔Example〕

Next, the present invention will be described in detail with reference to FIGS. 1 and 2 showing one embodiment thereof.

In FIG. 1, the same symbols as in FIG. 3 indicate the same or corresponding ones, and (6A) and (6B) are provided in the VTR section (1) instead of the common reproducing circuit (6) in FIG. There are two playback circuits, a playback amplifier (8A) and (8B), respectively.
With FM demodulation circuit (10A), (10B), head (2A),
(2B) playback signals are processed respectively and TBC section (13)
To output separately.

(21A) and (21B) are two A / D conversion circuits provided in place of the conversion circuit (21) shown in FIG.
It is connected to each of A) and (10B). (22A), (2
2B) are two reproduction memory circuits provided in place of the memory circuit (22) of FIG. 3, which are the first line memory (22Aa), (22Ba) and the second line memory (22Ab), respectively.
(22Bb), and the memory circuit (22A) has a conversion circuit (21B).
Memory circuit (22B) is connected to A) and conversion circuit (21B)
It is connected to the.

(23A) and (23B) are two time axis error detection circuits provided in place of the detection circuit (23) of FIG. 3, and the detection circuit (23A) is connected to the conversion circuit (21A). The conversion circuit (23B) is connected to the conversion circuit (21B). (2
7) is a synchronization deviation detection unit connected to both detection circuits (23A) and (23B).

Reference numerals (24A) and (24B) denote two reproduction memory control circuits provided in place of the control circuit (24) shown in FIG. 3. The detection signals of the detection circuits (23A) and (23B) and the detection unit ( Based on the detection signal of 27), writing and reading of the memory circuits (22A) and (22B) are controlled.

(28) is a switch forming a signal synthesizing circuit, which synthesizes the signals read from the memory circuits (22A), (22B) and outputs the synthesized signal to the converting circuit (26).

(29) is a recording circuit block formed by the conversion circuit (16), the memory circuit (18), the additional circuit (19) and the conversion circuit (20), and (30) is the conversion circuit (21A), (21B), memory circuit. (22A), (22B), detection circuit (23A), (23B), control circuit (24A), (24B) and conversion circuit (26), detection unit (2
7), a regeneration block formed by the switch (28).

The difference between the device of FIG. 1 and the device of FIG. 3 is that VT
In the R section (1), reproduction circuits (6A) and (6B) are provided for each of the heads (2A) and (2B), and a switch (9) is provided.
Is omitted, and in the TBC section (11), the reproduction circuit (6
A), (6B) A reproduction processing circuit for two channels for correcting the time base error of each output signal, that is, a conversion circuit (21A), a memory circuit (22A), a detection circuit (24A).
Regeneration processing circuit and conversion circuit (21B), memory circuit (2
2B), a reproduction processing circuit of a detection circuit (24B), a synchronization deviation detection unit (27), and a switch (28) are provided,
The processing parts (17) and (25) are omitted.

Next, the recording and reproducing operation of FIG. 1 will be described with reference to FIG.

At the time of recording, the high-definition television signal input to the input terminal (12) is digitally converted by the conversion circuit (16) and then immediately input to the memory circuit (18). At this time, the memory circuit (18) is input. The divided signal is divided into recording recording lengths, time-compressed, and output to an additional circuit (19).

Further, the addition circuit (19) adds the negative horizontal sync signal and the burst signal to the gap generated by the time compression of the input signal.

The output signal of the additional circuit (19) is input to the recording circuit (3) via the conversion circuit (20), and the signal output from the conversion circuit (20) to the recording circuit (3) at this time is one vertical. The video signal of one vertical scanning period is obtained by adding the horizontal synchronizing signal and the burst signal to the high-definition television signal without any loss of the scanning period.

Further, the output signal of the conversion circuit (20) is recorded by the modulation circuit (4) and the amplifier (5) of the recording circuit (3) and supplied to the heads (2A) and (2B).

Since the winding angle of the tape (7) is larger than 180 °, the heads (2A) and (2B) trace the tape (7) at the same time during the superposition of the tracing start and trailing ends. In each track of 7), a video signal for one track having the same signal during the superposition period is recorded.

That is, if the segment switching timing signal at the time of recording / reproducing is the signal of FIG. 2 (a), the recording circuit (3) has a high level of one vertical scanning period without loss as shown in FIG. 2 (b). A video signal having a quality television signal is continuously input, and by the recording traces of the heads (2A) and (2B), each track of the tape (7) is before and after the head switching point as shown in FIG. The signal of each overlapping period, that is, the signal of the hatched portion (Z) in the same figure (b) is redundantly recorded as the signal of the hatched portion (Z ₁ ) or (Z ₂ ) at the beginning and the rear end of each track.

Next, at the time of reproduction, the reproduction traces of the heads (2A) and (2B) are used to convert the heads (2A) and (2B) to the amplifier (8A),
A reproduction signal of one track having a hatched portion (Z ₁ ) or (Z ₂ ) in FIG. 2 (c) is alternately output to (8B). At this time, amplifiers (8A), (8B) and a demodulation circuit are output. (10A), (1
0B), the reproduction signals of the heads (2A) and (2B) are separately reproduced.

The reproduced signals of the heads (2A) and (2B) demodulated by the demodulation circuits (10A) and (10B) are converted into conversion circuits (21A) and
(21B) is input to each of the conversion circuits (21A), (21
By B), the reproduction signals of the heads (2A) and (2B) are digitally converted.

Further, the reproduction signal of the head (2A) via the conversion circuit (21A) is input to the memory circuit (22A) and the detection circuit (23A), and the reproduction signal of the head (2B) via the conversion circuit (21B) is stored in the memory. Input to the circuit (22B) and the detection circuit (23B).

Then, the detection circuits (23A) and (23B) separate and extract the negative horizontal sync signal and the burst signal from the input signal,
The time axis error of the input signal is detected, and, for example, the detection signal of the detected error level is sent to the control circuit (24A),
(24B) Output to each.

Further, the detection section (27) compares the horizontal synchronization signals input via both detection circuits (23A) and (23B), and the head (2A)
Of the synchronization signal between the reproduction signal of the head and the reproduction signal of the head (2B), that is, the synchronization deviation between the tracks is detected, and the detection signal of the detected correction level of the synchronization deviation is sent to the control circuits (24A) and (24B), respectively. Output.

Further, the control circuits (24A) and (24B) are connected to the memory circuit (22
A) and (22B) are controlled respectively for writing and reading, and the memories (22Aa), (22Ba) and the memories (22Ab), (22Bb) are controlled to write and read in reverse, and the head (2A), (22A) 2
B) Only the high-definition television signal in each reproduced signal is time-expanded and read out from each of the memory circuits (22A) and (22B). At this time, the detection signals of the detection circuits (23A) and (23B) and the detection unit are detected. Based on (27) and the detection signal, the write timing of each of the memory circuits (22A) and (22B) is variably controlled according to each of the detected time axis error and the synchronization shift, and the memory circuits (22A) and (22A), 22B) The time axis error of each output signal and the synchronization deviation between the output signals of the memory circuits (22A) and (22B) are corrected.

That is, the control circuits (24A) and (24B) are connected to the detection circuit (23
Based on the detection signals of (A) and (23B), the write timing of each of the memory circuits (22A) and (22B) is changed according to the time axis error of the reproduction signals of each of the heads (2A) and (2B). , Based on the detection signal of the detection section (27), the synchronization signals of the reproduction signals of the heads (2A) and (2B) are written in the memory circuits (22A) and (22B) at the same timing and arranged in H. Correction of time axis error and correction of synchronization deviation are performed.

Further, by controlling the read timing of the control circuits (24A) and (24B), the additional circuits (19) from the reproduction signals of the heads (2A) and (2B) are output from the memory circuits (22A) and (22B). The high-definition television signal excluding the signal added by is read out.

The signals read from the memory circuits (22A) and (22B) are combined by a switch (28) that switches in synchronization with the segment switching timing signal, and then output through a conversion circuit (26). The conversion circuit (26) outputs the signal to the terminal (14), and at this time the time axis error and the synchronization deviation of the output signals of the memory circuits (22A) and (22B) are corrected.
As shown in FIG. 2 (d), the signal output from the same is a shaded portion (Z) 'corresponding to the shaded portion (Z) in FIG. 2 (b), that is, a portion where the switch (28) is switched. The H-arrangement is performed so that skew distortion does not occur, resulting in a complete high-definition television signal in one vertical scanning period without skew distortion.

Therefore, in the case of the apparatus shown in FIG. 1, segment recording that divides and records a high-definition television signal in one vertical scanning period into two tracks prevents skew distortion at the time of reproduction and completely records and reproduces without loss. can do.

Although the video signals to be recorded and reproduced are high-definition television signals, that is, band-compressed video signals for high-definition television broadcasting in the above-described embodiment, the video signals to be recorded and reproduced are of the high-definition television broadcasting baseband. Of course, various video signals such as video signals and video signals of standard television broadcasting may be used.

Further, in the above embodiment, since the time axis error at the time of reproduction is corrected by the negative horizontal synchronizing signal and the burst signal added at the time of recording, the TBC section (11) is provided with the recording processing block (29). At the same time, the memory circuits (22A) and (22B) of the reproduction processing block (30) of the TBC section (11) are used to extend the time. If the error can be corrected, it is not necessary to add a signal for correcting the time base error. Therefore, the TBC section (11) is provided with only the reproduction processing block (30) and the memory circuits (22A), (22B ), It is only necessary to correct the time axis error and the synchronization deviation.

Further, it is needless to say that the present invention can be applied when the number of rotary heads, the number of tracks to be dividedly recorded, and the like are different from those of the embodiment.

In addition, the detection signal of the detection unit (27) is sent to the control circuit (24A),
(24B) and supply only to one of the heads (2A),
It is also possible to correct the synchronization deviation with reference to either one of the reproduction signals of (2B).

〔The invention's effect〕

As described above, according to the segment recording type video tape recorder device of the present invention, a plurality of rotary heads for simultaneously tracing the magnetic tape during the superposition period at the start and the end of the trace allows the video signal in one vertical scanning period to be recorded in a plurality of tracks. In addition to separately recording and reproducing each head reproduction signal at the time of reproduction, the reproduction signal of each head after reproduction processing is corrected for time axis error at all head switching points and between tracks. Synchronous deviation is corrected and then combined to obtain a video signal in one vertical scanning period. Therefore, skew distortion during reproduction is prevented in the vertical blanking period as well as in the period of the signal forming the screen, and one vertical scanning is performed. A complete video signal in the scanning period can be divided into a plurality of tracks and recorded and reproduced.

[Brief description of drawings]

1 and 2 show an embodiment of a segment recording type video tape recorder device of the present invention. FIG. 1 is a block diagram, FIGS. 2 (a) to 2 (d) are timing charts for explaining the operation, FIG. 3 is a block diagram of a conventional segment recording type video tape recorder, and FIGS. 4 (a) to 4 (f).
Is a timing chart for explaining the operation of FIG. (1) …… VTR section, (2A), (2B) …… Rotary head,
(3) …… Recording circuit, (6A), (6B) …… Reproducing circuit,
(7) …… Magnetic tape, (11) …… TBC part, (22A),
(22B) …… Playback memory circuit, (23A), (23B) …… Time axis error detection circuit, (24A), (24B) …… Playback memory control circuit, (27) …… Synchronous shift detection unit, (28 ) …… Switch.

Claims (1)

[Claims] 1. A head for tracing end and a head for tracing start are provided with a plurality of rotary heads for recording / reproducing for simultaneously tracing a magnetic tape during a superposition period before and after a head switching point, and recording / reproducing of each head. In a helical scan type segment recording type video tape recorder which divides a video signal for one vertical scanning period into a plurality of tracks of a magnetic tape by tracing and records and reproduces the video signal input at the time of recording. A recording memory circuit that divides the output into time intervals and outputs the compressed time, an additional circuit that adds a signal for time axis error correction to a gap generated by the time compression of the recording memory circuit, and an output circuit that outputs the additional signal. The video signal for one vertical scanning period is recorded, and the video signal is recorded on each head so that the same signal is recorded during the overlapping period of each track. A common recording circuit for supplying the same, a plurality of reproducing circuits for reproducing the reproduced signals of the respective heads and outputting them separately, and a plurality of reproducing circuits for time-expanding the video signals of the output signals from the respective reproducing circuits. The reproduction memory circuit, a plurality of time axis error detection circuits for detecting time axis errors of the output signals from the respective reproduction circuits, and the synchronization signals in the output signals from the respective reproduction circuits are compared, and A sync deviation detecting section for detecting a sync deviation between the reproduction signals, and a write timing of each of the reproduction memory circuits based on the detection signals of the time axis error detecting circuits, and based on the detection signals of the sync deviation detecting section. The write timing of each reproduction memory circuit is made uniform, and the reproduction circuit is added from the reproduction memory circuit by controlling the read timing of each reproduction memory circuit. A plurality of memory control circuits for reading out the video signals except the signal and a signal synthesizing circuit for synthesizing the signals read out from the respective reproducing memory circuits and continuously outputting the reproduced video signals for one vertical scanning period. A segment recording type video tape recorder device characterized by the above.