JPH11283297A - Time-lapse video tape recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a time-lapse video tape recorder capable of preventing the quality deterioration of recording even when track bending occurs. SOLUTION: Recording signals equivalent to one track are intermittently outputted at equal intervals by providing a pause period S4 before/after a time axis, a recording tape is caused to stop running in the pause period S4, the recording tape is started for fixed-speed running at the time of recording start of one track, and the fixed-speed transport of the recording tape is stopped at the time of recording the end of one track. Track bending occurs in the beginning and end of a track in the recording locus of a track, a previously recorded track and a track for subsequent writing are arranged side by side without overlapping, and thus overwriting is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a time lapse video tape recorder.

[0002]

2. Description of the Related Art When recording a monitoring image for a long period of time, a time-lapse video tape recorder is used which records a video signal for each unit screen of one field or one frame by intermittently running a magnetic tape.

A conventional time lapse video tape recorder is configured as shown in FIGS. The signal processing circuit 1 shown in FIG. 5 is for compressing a video signal for one frame and recording it on ten tracks.
The signal processing circuit for DV compression for C corresponds to this. As shown in FIG. 6A, the signal processing circuit 1 intermittently outputs a video signal of 10 tracks and 1 frame after a pause period S2 for 4 tracks. On the other hand, the running control of the magnetic tape 6 loaded on the cylinder 3 is managed by the tape running control unit 8, and controls the rotation of the capstan 7 in synchronization with the signal output of the signal processing circuit 1.

Specifically, as shown in FIG. 6B, a recording period S during which a video signal is output from the signal processing circuit 1 is shown.
At 1, the magnetic tape 6 is run, and during the pause S2, the tape running is stopped. The rotary head to which the heads 4 and 5 are attached continuously rotates over periods S1 and S2.

A video signal output from the signal processing circuit 1 is recorded on a magnetic tape 6 by heads 4 and 5 via a recording circuit 2.

[0006]

FIG. 7 (a) shows a track pattern of the magnetic tape 6 when recording is performed as described above, and in a transition period when the magnetic tape 6 changes from constant speed running to running stop. And a transition time t1 when the magnetic tape 6 changes from stoppage to running at a constant speed.
In No. 2, there is a problem that the track bend occurs and the overwrite portions R1 and R2 in FIG. 7A occur, the track width of the portions becomes narrow, so-called thin track occurs, and the recording quality deteriorates. .

More specifically, FIG. 7B and FIG.
FIG. 2A is an exploded view of the heads 4 and 5 of the rotary head. The eighth in the recording period S1 in FIG.
The magnetic tape 6 like the track T8 and the ninth track T9
When the vehicle is traveling at a constant speed, the eighth track T8
The recording signal of the ninth track T9 is recorded by the head 4 on the magnetic tape 6 without the track being bent like the track pattern shown in FIG. 7C, and the recording signal of the ninth track T9 is recorded by the head 5 in the track pattern shown in FIG. Thus, the track is recorded on the magnetic tape 6 without bending.

In the transitional period when the magnetic tape 6 changes from constant speed running to running stop, as in the tenth track T10, the recording signal is applied by the head 4 to the position indicated by the end A as shown in FIG. Is recorded on the magnetic tape 6 in a state where the track is bent.

As can be seen by comparing FIGS. 7 (b) and 7 (c), the recording locus of the track bending of the track pattern T10 shown in FIG. 7 (c) corresponds to a part of the track pattern T9 shown in FIG. 7 (b). 9th track T recorded by overwriting
9 (the overwritten portion R1) is erased.

The above description is for the transitional period timing t1 at which the magnetic tape 6 changes from constant speed running to running stop, but at the transitional period t2 at which the magnetic tape 6 changes from running stop to constant speed running. The same applies to the case. In addition,
Reference numerals 9, 10, and 11 indicate the trajectories of the heads 4 and 5 during the suspension period S2. If the trajectory of the head 4 at the timing t2 of the transition period from the stop of traveling to the constant speed traveling is described in a superimposed manner, it is difficult to understand the trajectory, and only the trajectory of the portion is extracted and displayed in FIG.

It is an object of the present invention to provide a time-lapse video tape recorder which does not cause a decrease in recording quality even when track bending occurs.

[0012]

According to the time lapse video tape recorder of the present invention, a recording signal for one track to be sequentially recorded on each track is intermittently output at regular intervals by providing a pause period before and after a time axis to record. The tape stops running during the above-mentioned pause period, and at the start of recording for one track, the recording tape rises from stoppage to running at a constant speed, and at the end of recording for one track, the recording tape falls from running at constant speed to stop running. It is characterized by.

According to the present invention, in the recording trajectory of each track, track bends of the same shape occur at the beginning and end of the track, and the previously recorded track and the track to be written later are arranged without overlapping, so that overwriting is performed. Does not occur.
Therefore, the track is not thin.

[0014]

A time-lapse video tape recorder according to the first aspect of the present invention is a time-lapse video tape recorder that divides a video signal for a unit screen into a plurality of tracks and records the divided signals on a recording tape. A recording signal processing unit that intermittently outputs a recording signal for one track to be recorded at regular intervals with pauses before and after the time axis, and a recording signal generated by the recording signal processing unit that moves relative to the recording tape. A recording unit for recording and a tape running control unit for running the recording tape intermittently in synchronization with the intermittent output of the recording signal of the recording signal processing unit are provided.

According to a second aspect of the present invention, there is provided a time lapse video tape recorder, wherein the recording signal processing section comprises:
A signal processing circuit for continuously outputting recording signals for a plurality of tracks constituting a unit screen; and a recording signal output from the signal processing circuit being input, and recording signals for one track being subjected to pause periods before and after the time axis. And a buffer for providing intermittent output at regular intervals.

According to a third aspect of the present invention, there is provided the time lapse video tape recorder according to the first aspect, wherein the recording unit is a rotary head including two heads which are arranged to face each other by 180 degrees and have different azimuth angles. .

An embodiment of the present invention will be described below with reference to FIGS. It is to be noted that components having the same functions as those in FIG.

FIG. 1 shows a time lapse video tape recorder of the present invention. A special buffer 9 is interposed between the signal processing circuit 1 and the recording circuit 2 shown in FIG. Has been changed to Others are the same as the conventional example shown in FIG.

The buffer 9 is configured as follows.
The signal processing circuit 1 shown in FIG. 5 has been described as generating a recording signal of 10 tracks and 1 frame during the recording period S1 and repeatedly outputting a recording signal of the next 10 tracks and 1 frame after the pause period S2. In the embodiment, as shown in FIG. 2A, a description will be given assuming that a recording signal of four tracks and one frame is generated and a recording signal of the next four tracks and one frame is repeatedly output after a pause period S2 for eight tracks. .

The recording signal processing section 10 is composed of the signal processing circuit 1 and a buffer 9, and the buffer 9 is shown in FIG.
And a recording period S3 for outputting a recording signal for one track and a pause period S4 for two tracks as shown in FIG.
, And the recording signal of the next track is output.

The tape running control unit 8 which is operated in synchronization with the output timing of the recording signal from the buffer 9 has a function as shown in FIG.
As shown in (b), at the start of recording for one track from the buffer 9, the recording tape is started from stoppage to running at constant speed, and at the end of recording for one track, the recording tape is dropped from running at constant speed to stop for running. Is configured.

FIG. 4B shows the recording locus of the head 4, and FIG. 4C shows the recording locus of the head 5. The heads 4 and 5 are rotating heads which are arranged 180 degrees opposite to each other and have different azimuth angles.

The head 4 raises the recording tape from running stop to running at a constant speed, and falls to running stop as shown in FIG.
As shown in (1), the recording signal of the first track T1 is recorded on the magnetic tape 6 first, and then the recording tape is started from running stop to running at a constant speed in response to the recording signal on the second track T2, and then dropped to running stop. In the meantime, the head 5 records the recording signal of the second track T2 on the magnetic tape 6 as shown in FIG.

Next, in response to the recording signal of the third track T3, the recording tape is raised from stoppage to running at a constant speed and then stopped during running, and the head 4 is moved to the third position as shown in FIG. The recording signal of the track T3 is recorded on the magnetic tape 6.

Next, in response to the recording signal of the fourth track T4, the head 5 moves the recording tape from the running stop to the constant speed running to the running stop, and the head 5 is moved to the fourth speed as shown in FIG. The recording signal of the track T4 is recorded on the magnetic tape 6.

In this manner, recording of one frame composed of four tracks is completed, and thereafter, each frame is recorded in the same manner. As described above, when the recording signals are recorded by the heads 4 and 5, the magnetic tape 6 rises from the stop of traveling to the constant speed traveling and falls to the stop of traveling. As can be seen from FIGS. 4 (b) and (c), track bends Bs and Be occur.

The actual recording locus is such that the recording locus of the head 4 in FIG. 4B and the recording locus of the head 5 in FIG. 4C overlap as shown in FIG. 4A, and FIG. As shown in FIG. 7, the speed change of the magnetic tape 6 is made the same during recording on any track, so that the second track T2
Is recorded without overwriting a part of the recording trajectory of the first track T1, the recording trajectory of the third track T3 is recorded without overwriting a part of the recording trajectory of the second track T2. The recording track of the track T4 is recorded without overwriting a part of the recording track of the third track T3.

It is to be noted that all the tracks recorded in this manner have track bends, but during reproduction, FIG.
As shown in (d), by using a reproducing head having a reading width substantially equal to or wider than the track width W having the track bending, good reproduction can be realized.

Therefore, according to this embodiment, it is possible to realize recording without deterioration in recording quality despite the fact that the recording track has a track bend. The recording signal processing unit 10 of the above-described embodiment converts the recording signal continuously output from the signal processing circuit 1 for four tracks of one frame via the buffer 9. When the video signal is output in the signal format of (b), the format conversion by the buffer 9 is not required.

[0030]

As described above, in the time-lapse video tape recorder of the present invention, a recording signal for one track to be sequentially recorded on each track is intermittently output at regular intervals by providing a pause before and after the time axis. The tape stops running during the above-mentioned pause period, and when the recording for one track is started, the recording tape rises to the constant speed running from the stop of the running, and when the recording for one track ends, the recording tape falls from the constant speed running to the running stop. However, the recording track of each track has the same shape at the beginning and end of the track,
Since the previously recorded track and the track to be written later are arranged without overlapping, the track is not thinned due to overwriting, so that recording / reproduction without deteriorating the recording quality can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a time-lapse video tape recorder according to an embodiment of the present invention.

FIG. 2 is a diagram showing an output signal waveform of a signal processing circuit and an output signal waveform of a buffer according to the embodiment;

FIG. 3 is a diagram showing a relationship between an output signal waveform of a buffer and a traveling speed of a recording tape according to the embodiment;

FIG. 4 is an explanatory diagram of a recording track and a reproduction track width according to the embodiment;

FIG. 5 is a configuration diagram of a conventional time-lapse video tape recorder.

FIG. 6 is a diagram showing a relationship between an output signal waveform of the signal processing circuit of the conventional example and a traveling speed of a recording tape.

FIG. 7 is an explanatory diagram of a recording track of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Signal processing circuit 2 Recording circuit 3 Cylinder 4, 5 head 6 Magnetic tape (recording tape) 7 Capstan 8 Tape running control part 9 Buffer 10 Recording signal processing part S1 Recording period S2 Pause period S3 Output recording signal for one track Recording period S4 Pause period following recording period S3 T1 First track T2 Second track T3 Third track T4 Fourth track Bs Track bend at start of track Be Track bend at end of track W Track width of read head

Claims (3)

[Claims] 1. A time-lapse video tape recorder which divides a video signal for a unit screen into a plurality of tracks and records the divided signals on a recording tape. A recording signal processing unit for intermittently outputting at regular intervals with a pause period provided therein, a recording unit for moving relative to a recording tape and recording a recording signal generated from the recording signal processing unit, and a recording signal for the recording signal processing unit A time lapse video tape recorder provided with a tape running control section for running a recording tape intermittently in synchronization with an intermittent output of the tape. 2. A recording signal processing unit, comprising: a signal processing circuit for continuously outputting recording signals for a plurality of tracks constituting a unit screen; and a recording signal output from the signal processing circuit being input for one track. 2. A time-lapse video tape recorder according to claim 1, further comprising a buffer for intermittently outputting the recording signal at regular intervals with a pause before and after the time axis. 3. The time lapse video tape recorder according to claim 1, wherein the recording section is a rotary head including two heads which are arranged to face each other by 180 degrees and have different azimuth angles.