JPS5928261A - Recording and reproducing device of video signal - Google Patents

Abstract

PURPOSE:To have a quick program search with a simple operation even for a small video recording time, by providing a reproducing means for a joint signal and a timing means which counts the time after reproduction of the joint signal, and changing the working mode for the reproduction time of the joint signal and when the timing means is active for a prescribed period of time. CONSTITUTION:A switch 17 and a switch 19 are set under a still reproduction and fast forward modes respectively, and a switch 21 is turned on. When the joint signal is reproduced in a rapid traverse mode, a counter 12 is reset. The value of the counter 12 is compared with the value of an after-mode time setting time 10, and the output of a comparator 16 is changed to L level. Then a switch 18 delivers the data given from the switch 17, and a still reproduction mode is set to give a still reproduction to the images at a joint area of the signal. The output of an oscillator 11 is counted by the counter 12 for a period equal to the set time of a circuit 15, and therefore, the output of the comparator 16 is changed again to H level. Then the switch 18 delivers again the data given from the switch 19 to reset the rapid transverse mode. This operation is carried out for each joint signal. Then a switch 25 is turned on when a desired signal is obtained while observing a reproduced screen. Thus a program is searched as desired.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video signal recording and reproducing apparatus, and more particularly to a video signal recording and reproducing apparatus capable of recording a seam signal that provides information about the change of a video signal.

Hereinafter, in this specification, a helical scan type video tape recorder (hereinafter referred to as VT) will be used as a video signal recording and reproducing device.
The explanation will be given by taking an example.

Conventionally, in a VTR, the above-mentioned joint signal has been recorded, for example, on an audio track for recording audio signals, a control track for recording control signals, and the like.

By reproducing this seam signal, a change in the video signal was detected, and the beginning of the video signal was also found.

For example, if a joint signal is recorded on the control track, first touch the head for playing the control signal to the control track in a high-speed tape mode such as fast forward or fast reverse. The main method has been to regenerate a seam signal and use the reproduced seam signal to stop or put the device into a Bose (pause) mode.

However, with the method described above, fast-forwarding or fast-reversing stops every time a seam signal is played back.Since the recording was mainly for television broadcasts, -( recording time is long 4 times → seam It didn't bother me much even if the fast-forward (fast-forward) or fast-reverse stopped every time I played a signal. However, in recent years, with the advent of systems that integrate a camera and a VTR, and the progress in the miniaturization of portable type VTRs, opportunities for users to take images with a video camera are increasing. In this case, since the recording time for one recording is short, if a seam signal is recorded every time the video signal changes, it will stop immediately if you fast-forward or fast-reverse for a short time, making it very difficult to find the beginning. It was becoming a hassle.

Therefore, in conventional high-end VTRs, cueing was performed by entering an address for each scene and counting the number of control signals, for example. However, according to this method, the equipment becomes large-scale and becomes very expensive. In addition, the operation of inputting addresses for each scene and the operation of selecting a desired address and locating the cue become extremely complicated, making it difficult to use.

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, an object of the present invention is to provide a video signal recording and reproducing device that can quickly locate the beginning of a desired video signal with a simple operation even when the recording time is short. Its features include: a seam signal recording means for recording a seam signal giving information about the transition of a video signal on a recording medium; a seam signal reproducing means for reproducing the seam signal; and a seam signal reproducing means for reproducing the seam signal. and a clock means for counting the time, and the mode of operation is changed when the seam signal is reproduced and when the clock means measures a predetermined time.

FIG. 1 is a diagram showing the configuration of a video signal recording and reproducing apparatus according to an embodiment of the present invention. 1 is a magnetic tape as a recording medium; 2 is a head for recording and reproducing video signals; 3.
3' is a recording/reproduction changeover switch which is connected to the R side in the figure during recording and to the P side in the figure during playback. A video signal input from a TV tuner or a video camera (not shown) is input to the video signal input terminal 5, and the video signal is input to the recording signal processing circuit 4.
It is made into a form suitable for magnetic recording, and recorded on the magnetic tape 1 by the head 2.

On the other hand, a trigger signal is supplied to the seam signal generation circuit 9 when the mode changeover switch 14 switches to recording mode, when the pause is released, or when the camera section (not shown) starts imaging.

16 is a terminal to which an imaging start signal from the camera section is input. The seam signal generation circuit 9 generates a seam signal when the above-mentioned trigger signal is input, and the seam signal is recorded by the seam signal recording/reproducing head 8 via the switch 6I. Although this joint signal recording and reproducing head 8 is not shown, it may also be used as a control head, a roll head, or an f-voice head.

If a seam white signal is recorded with such a configuration, even if recording and stopping are repeated many times in a short period of time, there is no need to perform any special operation to input the seam signal each time.

FIG. 2, (Φ) is a diagram for explaining the generation timing of the seam signal. In FIG. 2, numeral 29 indicates a video camera, and numeral 62 indicates a portable type VTR. Further, 30 is an imaging switch of the camera 29, 61 is a recording switch that commands recording, and 33 is a pause switch that commands a temporary stop of the apparatus.

FIG. 2(B) is a circuit diagram for explaining the function of the seam signal generating circuit 9 of FIG. 1. First, I will explain how it works when a video camera is not connected. The input side of the inverter 660 is grounded and its output is always at a low level. Therefore, at this time, the output of the AND gate 65 is directly supplied to the monomulti 68. The output η of the AND gate 35 becomes high level (only when the recording switch 61 is on and the pause switch 33 is off). Therefore, the input signal of the monomulti 68 rises when the recording switch 61 is turned on while the pause switch 66 is in the off state, and when the pause switch 66 is turned off while the recording switch 31 is in the on state. Since the trigger is generated at the rising edge of the monomulti 38 input, the gate circuit 40 is opened for a certain period of time from the rising edge of the input.

When the gate circuit 40 is open, the output of the oscillator 39 is output as a joint signal. The oscillation frequency of this oscillator 39 may be selected to a frequency that can be distinguished from signals other than the joint signal (for example, control signals and audio signals).

Next, the operation when the video camera 29 is connected will be explained. Terminal 13 and terminal 16' are short-circuited by a connector (not shown). When the imaging switch 6o on the camera 29 side is in an off state, the input of the inverter 36 is at a high level), and the output of the AND gate 37 is prohibited. When the imaging switch 6o is turned on while the output of the AND gate 35 is at a high level, the AND gate 67 outputs an output, triggering the monomulti 68 and recording the seam signal as described above.

Although not shown, if the imaging switch 30 is not turned on when the connector is connected, the recording operation on the VTR side is stopped.

A seam signal is recorded as described above.

Next, the operation of the video signal recording and reproducing apparatus shown in FIG. 1 during reproduction using a joint signal will be described. The system controller 22 controls each part 27 of the apparatus according to the mode changeover switch 14, the front mode setting switch 19, or the rear mode setting switch 17. If you do not want to perform playback using the seam signal, turn off the seam playback switch 21.
The changeover switch 20 supplies the data of the mode changeover switch 14 to a system controller 22.

When performing reproduction using the seam signal, the switch 21 is turned on and output data of the changeover switch 18 is supplied to the system controller 22.

The output data of the changeover switch 18 is the data of the front mode setting switch 19 until the seam signal is regenerated, and the data of the rear mode setting switch 1 for a predetermined time after the seam signal is regenerated.
This is based on the mode data set in step 7. Modes that can be set by the previous mode setting switch 19 include, for example, fast forward mode, fast backward mode, fast forward mode for searching, fast forward playback, fast backward playback, and the like. On the other hand, the modes set by the rear mode setting switch 17 are playback, slow playback,
Possible options include still playback and stop.

Now, the case where the rear mode setting switch is set to still playback and the previous mode setting switch is set to fast forward) will be explained. It is assumed that the seam reproduction command switch is in the on state. Data from the previous mode setting switch 19 is supplied to the system controller 22, and the tape 1 is fast-forwarded 9. At this time, when the seam signal recorded as described above is reproduced by the seam signal reproducing circuit 10 via the head 8 and the switch 6', the seam counter 12 is reset by the reproduced seam signal. Then, the output of the comparator 16, which compares the values of the counter 12 and the post-mode time setting circuit 15, changes from high level to low level.

Then, the changeover switch 18 outputs the data of the rear mode setting switch 17), and the apparatus enters the still playback mode and plays back the still image of the transition part of the video signal. If a value corresponding to, for example, 5 seconds is set by the post-mode time setting circuit 15, then when the counter 12 counts the pulses output from the crystal oscillator 11 for 5 seconds, the output of the comparator 16 changes to high level again. Then, the selector switch 18 again outputs the data of υ from the previous mode setting switch 19, and the apparatus returns to the fast forward mode. This operation is performed every time a joint signal is reproduced. Then, by looking at the reproduced screen and turning on the stop command switch when the desired video signal is obtained, it is possible to locate the beginning of the desired video signal.

According to the configuration of the embodiment of the present invention described above, the video signal is played back at every turn of the video signal9, and as soon as the video signal is played back for a predetermined period of time, the tape is fed at high speed), so that the played screen cannot be viewed. However, the desired video signal can be quickly located.

The circuit shown in Figure 2 (B) is an example of a system that combines a portable VTR and a video camera; however, for example, an integrated VTR that integrates a camera and a VTR
In this case, terminal 13 and terminal 13' may be shorted.

Also, the joint signal may be recorded on the control track or the audio track (although this is described, it may also be recorded on other tracks on the magnetic tape, or on other media synchronized with the movement of the magnetic tape). It is also possible to record.

Furthermore, although the present invention has been described using a VTR as an example, the present invention will be more effective if applied to a recording/reproducing apparatus whose purpose is to reproduce moving images.

As explained above (according to the present invention), even if the recording time of - times is short, it is possible to quickly locate the beginning of a desired video signal with a simple operation, and the cost can be reduced with a simple configuration. A video signal recording and reproducing device can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention, and FIG.
), but) are diagrams for explaining the generation timing of the seam signal. Reference numeral 1 denotes a magnetic tape as a recording medium, a joint signal recording/reproducing head from 8 companies, 9 a joint signal generating circuit, 10 a joint signal reproducing circuit, 12 a counter as a time measuring means, and 15 determining a predetermined time of the present invention. A rear mode time setting circuit, 18 a data changeover switch, and 22 a system controller. Applicant Canon Co., Ltd.

Claims (1)

[Claims] 1) A seam signal recording means for recording a seam signal giving information about the change υ of a video signal on a recording medium, a seam signal reproducing means for reproducing the seam signal, and a timer for measuring the time after the seam signal is reproduced. 1. A video signal recording and reproducing apparatus, comprising: a timer; and a video signal recording and reproducing apparatus, characterized in that the mode of operation is changed when the joint signal is reproduced and when the timer means measures a predetermined time.