JP2001043585A - Magnetic recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a frame dropout from occurring due to slackening of a tape caused when a magnetic tape is reversed in the running direction from the forward direction to the backward direction or vice versa, by controlling the device to hold the frame under reproducing when displaying a video signal of the frame immediately preceding to a frame under reproducing. SOLUTION: When the immediately preceding frame is reproduced, a reproducing direction reversing control part 7 reads a time code of a frame under reproducing at present from a tape position detecting part 4 and stores it. At the same time, the tape position detecting part 4 controls to freeze a video signal storage part 2 via a video signal freeze/release control part 3, and holds the state in which the video of the frame under reproducing at present is displayed on a monitor 8. Having wound the slack of the tape by driving a capstan 5 in the reverse direction, the reversing control part 7 makes the tape run in the reverse direction up to the stored time code position, and controls the video signal storage part 2 to be released from freezing via the release control part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus characterized in that the reproducing direction of a video can be changed while ensuring the continuity of a video signal obtained by reproducing a magnetic tape. .

[0002]

2. Description of the Related Art Generally, a video tape recorder which records and reproduces a video signal by a rotary magnetic head has a function of reproducing a recorded video in a reverse direction.

[0003] The following describes a conventional video playback state when the playback direction is reversed. FIG. 3 is a schematic diagram showing a conventional mechanism for transmitting the rotation of a capstan to a reel via an idler to wind up a magnetic tape.

In FIG. 3, reference numeral 31 denotes a cylinder on which a magnetic head for reproducing a signal recorded on a magnetic tape 40 is mounted, and 32 denotes a cylinder which pinches and rotates the magnetic tape 40 with a pinch roller to rotate the magnetic tape 40 at a predetermined speed. The capstan to be run, 33 and 34 are reels for feeding or winding the magnetic tape 40, 35 is an idler which is a mechanism for transmitting the rotation of the capstan 32 to the reels 33 and 34, and the idler 35 is driven by the rotation of the capstan 32. After moving to and engaging with either the reel 33 or the reel 34 on the side where the magnetic tape 40 is wound, the reel on the winding side is rotated and the magnetic tape 40 is wound on the reel. Three
Reference numeral 6 denotes a video signal storage unit for storing a video signal reproduced by a magnetic head attached to the cylinder 31 in frame units and displaying the frame on a monitor 37;
A capstan control unit 37 for controlling the traveling of the vehicle is a monitor for displaying a reproduced video.

[0005] The operation of the conventional video reproduction state when the reproduction direction is reversed will be described below.

First, the magnetic tape 40 is caused to travel in the direction of arrow A by the capstan 32, and a video signal recorded on the magnetic tape 40 is reproduced by the magnetic head attached to the cylinder 31 while the magnetic tape is traveling. The reproduced video signal is stored in the video signal storage unit 36, and the stored video signal is output to the monitor 37 for display.

When reversing the tape running direction, the reproducing position is reversed from the commanded position. That is, the rotation direction of the capstan 32 is reversed, and the rotation of the capstan 32 in the opposite direction is switched via the idler 35 from the reel 33 on which the magnetic tape 40 is wound to the reel 34, and reproduced immediately after the switching. The video signal is output to the monitor 37 and displayed.

[0008]

However, in the above-described conventional configuration, when the reproduction direction is switched from the direction of arrow A to the reverse direction or from the reverse direction to the direction of arrow A, the magnetic tape
Is required to be switched from the reel 33 to the reel 34 or from the reel 34 to the reel 33. To switch the reel on the take-up side, use the capstan 32
It is necessary to move the idler 35 by the rotation of, and to contact the reel, so that the torque in the opposite direction is transmitted. However, release the idler 35 from the reel on the current winding side,
There is a period during which torque is not transmitted to both reels until it comes into contact with the next reel on the winding side. Therefore, the magnetic tape 4 sent out by the rotation of the capstan 32
0 cannot be wound on either the reel 33 or the reel 34, and tape slack occurs. The video signal recorded at the point where the tape slack occurred is
Since the magnetic tape 40 is slightly floating with respect to the magnetic head, the recorded signal cannot be reproduced. Therefore, if the running direction of the tape is switched based on the position where the reproduced video is recorded, the tape slack occurs at the position where the video to be continuously reproduced is recorded. However, there has been a problem that frame skipping occurs due to lack of performance.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and prevents the skipping of frames caused by tape slack that occurs when the running direction of a magnetic tape shifts from a forward direction to a reverse direction or from a reverse direction to a forward direction. It is an object of the present invention to obtain a magnetic recording / reproducing apparatus which can ensure continuity of the magnetic recording / reproducing apparatus.

[0010]

To achieve this object, a magnetic recording / reproducing apparatus according to the present invention comprises a recording medium driving means for running a recording medium in which video signals are continuously recorded on a plurality of tracks in frame units. Recording medium travel amount detection means for detecting a travel amount of the recording medium using an FG signal output by rotation of the recording medium drive means, and a video signal obtained by reproducing from the recording medium in frame units. Video signal storage means for storing, video holding control means for controlling to hold the video signal stored in the video signal storage means in frame units, and absolute position in frame units for the video continuously recorded on the recording medium Recording medium position detecting means for detecting the time information to be used, inverting control means for inverting the reproduction direction of the recording medium, and video stored in the video signal storing means. And display means for displaying the signal,
When displaying the video signal one frame before the currently reproduced frame, the video holding control means controls to hold the display of the currently reproduced frame stored in the video signal storage means.

With this configuration, it is possible to prevent frame skipping caused by the tape slack that occurs when the running direction of the magnetic tape shifts from the forward direction to the reverse direction or from the reverse direction to the forward direction, thereby ensuring the continuity of the reproduced image. It is an object of the present invention to obtain a magnetic recording / reproducing device that can perform the above-described operations.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claims 1 and 2 of the present invention is directed to a recording medium driving means for causing a recording medium on which a video signal is continuously recorded on a plurality of tracks in frame units to travel, and the recording medium FG output by rotation of driving means
Recording medium travel amount detection means for detecting a travel amount of the recording medium using a signal, video signal storage means for storing a video signal obtained by reproducing from the recording medium in frame units, and the video signal storage means Video holding control means for controlling to hold the video signal stored in the frame unit, and a recording medium position detecting means for detecting time information which is an absolute position in a frame unit for the video continuously recorded on the recording medium, A reversal control unit for reversing the reproduction direction of the recording medium, and a display unit for displaying the video signal stored in the video signal storage unit, and displaying the video signal one frame before the frame being reproduced. At this time, the video holding control means controls to hold the display of the currently reproduced frame stored in the video signal storage means. It has the effect that the means to ensure the continuity of the image obtained.

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

(Embodiment 1) FIG. 1 is a block diagram of a reproduction direction inversion control according to Embodiment 1 of the present invention. In FIG. 1, reference numeral 1 denotes a video signal recorded on a magnetic tape as a recording medium. A video signal storage unit as video signal storage means for storing a video signal reproduced by the magnetic head mounted on the cylinder 1 and outputting the stored video signal to the monitor 8; A video signal storage freeze / release control unit that is a video holding control unit that freezes / freezes the video signal storage operation of the video signal storage unit 2, where “freeze” is a video signal stored in the video signal storage unit 2. Monitor 8
Means the operation to keep displaying. Reference numeral 4 denotes a tape position detecting unit which is a recording medium position detecting means for detecting a time code which is position information in a frame unit from a signal reproduced by a magnetic head mounted on the cylinder 1. Reference numeral 5 denotes a pinch roller (not shown). A capstan 6 for nipping a magnetic tape and running at a predetermined speed, 6 is a tape running means which is a recording medium running amount detecting means for counting a capstan FG signal output by rotation of the capstan 5 and detecting a magnetic tape running amount. The amount detector 7 monitors the time code output from the tape position detector 4 in response to the request for reversing the reproduction direction, and detects the amount of tape travel output from the tape travel detector 4, A reproduction direction inversion control unit, which is an inversion control unit for instructing the freeze / cancel control unit 3 to freeze / cancel, is a video signal memory. A monitor is a display means for displaying a video signal for displaying a video signal stored in 2. Here, as for the recording medium driving means, similarly to the above-described conventional technique, the tape is run by rotating the capstan, and the running direction is switched by bringing the idler into contact with the driven reel. ing.

FIG. 2 is a schematic diagram showing, in chronological order, positions traced by a magnetic head on a magnetic tape on which a video signal is continuously recorded in frame units according to the first embodiment of the present invention. Frame 1, frame 2, frame 3... Frame n, frame n +
1 (a natural number n), and the magnetic head reproduces the frame 3 one frame before from the state where the frame 4 on the magnetic tape has been reproduced in the forward direction (head position A). The tape travels to the position B in the forward direction, the position of the tape slack generated when the tape traveling direction is reversed is shifted, the traveling direction is reversed at this position, and the tape slack is reduced while traveling toward the head position C. Take up the frame 4 with the magnetic tape running after the head position C.
The operation of detecting the video of the frame 3 and reproducing the video signal of the frame 3 from the head position D to the head position E is shown.

The operation of the magnetic recording / reproducing apparatus of the present embodiment configured as described above will be described with reference to FIGS. 1, 2 and 3.

Frame 4 on the magnetic tape on which the video signal shown in FIG. 2 is recorded in the order of frame 1, frame 2, frame 3,... Frame n, frame n + 1 is reproduced in the forward direction. When reproducing the frame 3 one frame before the state after the head position A, that is, first, the reproduction direction inversion control unit 7 in FIG. 1 reads the time code of the currently reproduced frame 4 from the tape position detection unit 4. Remember.

At the same time, the tape position detecting section 4 instructs the video signal freeze / release control section 3 to freeze the video signal, and the video signal storage freeze / release control section 3 performs freeze control on the video signal storage section 2. Done, video signal storage unit 2
Holds the state in which the image of the frame 4 shown in FIG. 2 is output and displayed on the monitor 8 in FIG.

Thereafter, the reproduction direction reversal control unit 7 runs the capstan 5 from the head positions A to B in FIG. 2 while keeping the capstan 5 in the forward direction, that is, with the idler 35 shown in FIG. I do. Here, when traveling from the head position A to the head position B in FIG. 2, the reproduction direction reversal control unit 7 winds up the section in which the idler 35 generates a tape slack in which the reels 33 and 34 do not transmit torque and the generated slack. In order to travel the distance including the section, the traveling amount is controlled while monitoring the output from the tape traveling amount detection unit 6.

Next, the reproduction direction reversal control unit 7 shown in FIG. 1 reverses the running direction of the capstan 5 and runs it in the reverse direction. After reversing the tape running direction and winding up the tape slack generated, the reproducing direction in FIG. The head position C is reached. After reaching the head position C in FIG. 2, the tape is run in the reverse direction while monitoring the output of the tape position detection unit 4 to the time code position stored when the reproduction direction inversion control unit 7 in FIG. After detecting the stored time code position, the video signal storage freeze / release control unit 3 releases the video signal freeze. The video signal storage freeze / release control unit 3 performs freeze release control on the video signal storage unit 2, and the video signal storage unit 2 re-stores the reproduced video of the frame 3 shown in FIG. The video output to 8 is switched from frame 4 to frame 3 in FIG.

As described above, according to the present embodiment, frame skipping due to tape slack which occurs when the running direction of the magnetic tape 10 shifts from the forward direction to the reverse direction or from the reverse direction to the forward direction is prevented, and the image continuation is prevented. It is possible to perform video reproduction with ensured performance.

[0022]

As described above, the present invention prevents skipping of frames due to tape slack that occurs when the running direction of the magnetic tape shifts from the forward direction to the reverse direction or from the reverse direction to the forward direction.
An excellent effect that video reproduction can be performed while ensuring video continuity can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram of a reproduction direction inversion control according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing, in chronological order, positions where a magnetic head traces a magnetic tape on which a video signal is continuously recorded in frame units according to the first embodiment of the present invention;

FIG. 3 is a schematic diagram showing a conventional mechanism for transmitting rotation of a capstan to a reel via an idler and winding up a magnetic tape;

[Explanation of symbols]

 2 Video signal storage unit 3 Video signal storage freeze / cancel control unit 4 Tape position detection unit 5 Capstan 6 Tape travel amount detection unit 7 Reproduction direction inversion control unit 8 Monitor 10 Magnetic tape

Continued on the front page (72) Inventor Keigo Maeda 1-1 1-1 Matsushita-cho, Ibaraki-shi, Osaka F-term Matsushita Avicy Technology Co., Ltd. F-term (reference) 5C018 JA02 JA04 JB05 JC07 NA01 NA06 5C053 FA21 FA27 HA25 JA22 KA03 KA24 LA06 5D104 AB11 AC01 AC34 MB06 MC15 MF06

Claims (2)

[Claims] 1. A recording medium driving means for running a recording medium in which a video signal is continuously recorded on a plurality of tracks in frame units, and said recording medium using an FG signal output by rotation of said recording medium driving means. A traveling amount detecting means for detecting a traveling amount of a recording medium, a video signal storing means for storing a video signal obtained by reproducing from the recording medium in frame units, and a video signal stored in the video signal storing means as a frame. Video holding control means for controlling to hold in units of recording, recording medium position detecting means for detecting time information which is an absolute position of a frame unit with respect to a video continuously recorded on the recording medium, and a reproduction direction of the recording medium Control means for inverting the video signal, and display means for displaying the video signal stored in the video signal storage means. The magnetic recording / reproducing apparatus according to claim 1, wherein when displaying the video signal, the video holding control unit controls to hold the display of the currently reproduced frame stored in the video signal storage unit. 2. A recording medium driving means for causing a tape on which a video signal is continuously recorded on a plurality of tracks in a frame unit to travel, and the tape running using an FG signal output by rotation of the recording medium driving means. Recording medium travel amount detection means for detecting the amount, video signal storage means for storing a video signal obtained by reproducing from the tape in frame units, and holding the video signal stored in the video signal storage means in frame units Image holding control means for performing control to perform the operation, recording medium position detecting means for detecting time information that is an absolute position in a frame unit for an image continuously recorded on the tape, and inversion for inverting the reproduction direction of the tape. Control means; and display means for displaying the video signal stored in the video signal storage means, wherein the video signal one frame before the frame being reproduced is displayed. When displaying, the video holding control unit holds the display of the currently reproduced frame stored in the video signal storage unit, switches the operation of the recording medium driving unit, and takes the slack of the tape. Magnetic recording and reproducing device.