JPH03283882A - Video recording and reproducing device - Google Patents

Abstract

PURPOSE:To eliminate the irregularities of an image by taking synchronism between the vertical synchronizing signal of a camera input signal or a video tape reproducing signal before switching and that of the video tape signal or the camera input signal to be switched. CONSTITUTION:When a reproducing PB button is depressed, a VTR part 21 is set to an operating state by a command from a system controller 17, and the vertical synchronizing signal (g) of a synchronizing signal generation circuit 1 is selected by a first change-over switch 22, and is inputted to a phase comparator 11, and the operation of a motor control circuit and the driving of a drum motor are performed synchronizing with the vertical synchronizing signal (g) of a camera part 20, and it is extracted from a magnetic tape 5 with magnetic heads 6a, 6b. Therefore, a signal in which the positions of the vertical synchronizing signals of a camera signal (b) and a reproducing signal (c) nearly coincide with each other can be generated, and the synchronism with the vertical synchronizing signal (g) can be taken, and it goes to the one in which the connection of the vertical synchronizing signals is performed satisfactorily even at a switching part from the camera signal (b) to the reproducing signal (c). In such a way, the irregularities of a display picture can be eliminated.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention converts an optical image of a captured object into an electrical signal, and converts the electrical signal into an image that can be recorded and played back on a magnetic tape using a rotating magnetic head. The present invention relates to a recording/reproducing device.

[Conventional technology]

Conventionally, as this type of video recording and reproducing apparatus, there is, for example, a camera-integrated VTR.

FIG. 4 is a block diagram of a conventional camera-integrated VTR.

As shown in the figure, a camera-integrated VTR has a camera section (2
0) and a video tape recorder section (hereinafter referred to as VTR section) (-21).

The camera unit (20) includes a lens (4) that inputs an optical image of a subject, a solid-state image sensor (2) that forms an optical image from the lens, and a synchronization signal generation circuit (1) that generates a synchronization signal. ) and a conversion means (3) for converting the optical image formed on the solid-state image sensor into an electrical camera signal based on the synchronization signal, and the conversion means applies a driving pulse to the solid-state image sensor. It consists of a drive circuit (3a) that supplies and reads out the captured image data as a temporally continuous electric signal, and a camera signal processing circuit (3b) that converts the read electric signal into a normal television signal.

Further, the VTR section (21) includes a rotating drum (7),
The camera unit (20) is fixed to this rotating drum (7).
a magnetic head (6a) for recording and reproducing output signals from the magnetic tape (5);

(6b), a changeover switch (14) that alternately switches between the magnetic heads (6a) and (6b) and connects them to the video signal processing circuit (15), and a rotation pulse that detects the rotational phase of the magnetic head. A generator (8), a waveform shaping circuit (13) that converts the rotational pulse signal from the rotational pulse generator into a head switching signal, a reference oscillator (12) that oscillates a reference signal, and a motor control circuit using the reference signal. Circuit (10)
The phase comparator circuit (11) controls the rotation of the drum motor (9) via the phase comparator circuit (11).

Further, a changeover switch (16) for outputting a video signal by switching between a camera signal from the camera section (20) and a magnetic tape playback signal from the VTR section (21), and a playback (PB) button (18) are provided. ), a stop button (19), and other operation buttons to control a camera section (20) and a VTR section (21).

Next, the operation of the conventional example will be explained below.

First, at the time of camera input to the camera unit (20), an optical image of the subject input through the lens (4) is formed on the solid-state image sensor (2).

Next, under the control of the system controller (17), the synchronization signal generation circuit (1) outputs a synchronization signal, and based on this synchronization signal, the drive circuit (3a) drives the solid-state image sensor (
2) The solid-state image sensor (2) is driven so as to output the optical image formed in step 2 as a temporally continuous electrical signal.

The electrical signal output from the solid-state image sensor (2) is converted into a camera signal (ordinary television signal) by the operation of the camera signal processing circuit (3b) based on the synchronization signal from the synchronization signal generation circuit (1). Ru.

On the other hand, when playing a videotape in the VTR section (21) (PB
time), the magnetic tape (5) is connected to the magnetic head (6a).
), the video signal extracted by (6b) is processed by the changeover switch (14) based on the head switching signal (m) obtained by converting the rotational pulse signal from the rotational pulse generator (8) by the waveform shaping circuit (13). Selected sequentially. This selected video signal is converted into a video tape playback signal by a video signal processing circuit (15) and output.

Further, the head switching signal (m) is transmitted to the phase comparator circuit (1
1), and its phase is compared with the reference signal (h) generated by the reference oscillator (12).

The output of the phase comparison circuit (11) determines the control amount of the motor control circuit (10), and by controlling the drum motor (9), phase synchronization of the rotation of the rotary drum (7) is performed. .

The camera signal (b) outputted from the camera section (20) and the playback signal (C) outputted from the VTR section (21) are appropriately selected by a changeover switch (16) to output the video signal. (e) is output to the outside.

Next, by using the changeover switch (16), the states of the transition from the camera signal to the videotape playback signal and the transition from the videotape playback signal to the camera signal are set based on FIGS. 5 and 6. This will be explained with reference to FIG.

First, the camera unit (20) shown in FIG. is output and selected by the changeover switch (16) to become the output video signal (e). This signal state is shown in the first half of FIG. 5 before the PB button is pressed.

Therefore, when the PB button (18) is pressed, the VTR unit (21) receives a command from the system controller (17).
) becomes operational.

However, the output switching signal (d) from the system controller (17) to the changeover switch (16) does not change immediately, and the camera signal (b) from the camera signal processing circuit (3b) remains as the output video signal (e). Output (
(See Figure 5).

Then, the playback signal (
c) rises to the normal reproduction state and becomes normal, the output switching signal (d) from the system controller (17) changes. As a result, the changeover switch (16)
is a video signal processing circuit (15) from the camera signal (e)
The reproduced signal (c) is selected as the output video signal (e).

In this case, since there is no correlation between the vertical synchronization signal positions of the camera signal and the playback signal, the signal is cut off in the middle of the output video signal (e), as shown in the circle A with the dashed-dotted line in Fig. 5, and the signal has a different phase. The signal waveform changes to the signal of . When this output video signal (e) is viewed on a monitor screen, the screen appears distorted.

Conversely, in the reproduction state of the VTR section (21), the reproduction signal (c) from the video signal processing circuit (15) is selected by the changeover switch (16) and becomes the output video signal (e). This signal state is shown in the first half of FIG. 6 before the 5TOP button is pressed.

Therefore, when the stop button (19) is pressed, when the camera signal (b) from the camera signal processing circuit (3b) becomes normal, the changeover switch ( 16) or the camera signal (b) is selected as the output video signal (e).

In this case, since there is no correlation between the vertical synchronization signal positions of the reproduction signal (c) and the camera signal (b), the phases differ each time. For example, as shown in the dot-dash line circle B in FIG. 6, the signal is cut off in the middle of the output video signal (e), resulting in a discontinuous signal state, and an incomplete video signal based on the phase difference is output. There is.

When this output video signal (e) is viewed on a monitor screen, the screen appears distorted.

[Problems to be Solved by the Invention] As described above, in the case of a conventional video recording and reproducing device, the vertical synchronization phase of the camera signal output from the camera section is determined by the synchronization signal generation circuit and the phase of the vertical synchronization output from the VTR section. Since the vertical synchronization phase of the reproduced signal is determined by the reference oscillator, there was no correlation between the phases of the two vertical synchronization signals.

For this reason, in the output video signal that is output by switching between the camera signal and the playback signal using a switch, the phase of the vertical synchronization signal is different when switching between the two signals, resulting in poor screen connection and synchronization of the display screen. There was a problem that the screen was distorted greatly.

The present invention was made with the aim of solving the above-mentioned problems, and at the time of transition from the camera signal to the playback signal, and from the playback signal to the camera signal, the vertical synchronization signal of both signals is It is an object of the present invention to provide a video recording and reproducing device that can improve the connection during switching by matching the phases and prevent the display screen from being disturbed.

[Means to solve the problem]

In order to solve the above problems, the video recording and reproducing apparatus of the present invention includes a camera unit that converts an optical image signal of a subject into a camera signal based on a synchronization signal generated by a synchronization signal generation circuit, and outputs the camera signal; A means for recording a camera signal from the camera unit on a magnetic tape is provided, and the video information recorded on the magnetic tape is read out based on a reference signal generated by a reference signal oscillator, converted into a video signal, and outputted. The camera section includes a VTR section and a selection means for switching and selecting between the camera signal and the video signal and outputting the selected signal to the outside as an output video signal, and the camera section converts the output video signal from the video signal into the camera signal. The VTR section includes first signal switching means for externally synchronizing by replacing the reference signal in place of the synchronization signal for a predetermined period of time before switching, and the VTR section is configured to switch the output video signal from the camera signal to the video signal. The apparatus is characterized in that it further includes second signal switching means for replacing the synchronization signal in place of the reference signal for a predetermined period of time for external synchronization.

[Effect]

According to the above configuration, the camera signal can be synchronized with the video signal immediately before switching the output video signal from the video signal to the camera signal, and thereby the phase difference between the two signals related to the switching of the output video signal can be removed.

Further, even when switching the output video signal from a camera signal to a video signal, the video signal can be synchronized with the camera signal, so the above-mentioned phase difference does not occur in this case as well.

Therefore, the output video signal can be switched smoothly without causing any disturbance in the video.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a video recording and reproducing apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

Incidentally, the same or equivalent members as in FIG. 4 of the conventional example described above are given the same reference numerals, and redundant explanation will be omitted below.

The characteristic configuration of this embodiment is that the VTR section (21) receives the reference signal from the reference oscillator (12) and the camera section (21).
0) and the vertical synchronizing signal from the synchronizing signal generating circuit (1) and inputting it to the phase comparator circuit (11).
It is equipped with a changeover switch (22).

Further, in the camera section (20), a synchronization signal generation circuit (
1) and external synchronization, which inputs a reference signal from the reference oscillator (12) of the VTR section (21) using an external synchronization input terminal (24). ing.

In such a configuration, the operation of the video recording and reproducing apparatus of this embodiment will be described below.

As shown in Figure 1, during camera input, the lens (
The optical image input via 4) is formed on the solid-state image sensor (2). This optical image is generated by the drive circuit (
3a) drives the solid-state image sensor (2) to extract an electrical signal, converts it into a television signal in a camera signal processing circuit (3b), and outputs it as a camera signal (b). This camera signal (b) is selected by a changeover switch (16) and becomes an output video signal (e).

Also, during videotape playback, the phase comparator circuit (11)
, the motor control circuit (10), the drum motor (9), etc., to drive the magnetic head (6a) on the rotating drum (7),
At (6b), a signal is extracted from the magnetic tape (5). The signal is then processed by a video signal processing circuit (15) via a changeover switch (14) to become a playback signal (C), which is selected by a changeover switch (16) to become an output video signal (e). .

The operation up to this point is the same as in the conventional example.

Next, the states at the time of transition from camera input to videotape playback and from videotape playback to camera input will be explained using FIGS. 2 and 3 and with reference to FIG. 1.

First, as shown by the changeover switch (23) in FIG. 1, in the camera input state, the second changeover switch (23) is switched to operate the synchronization signal generation circuit (1) in internal synchronization. .

Based on the synchronization signal from the synchronization signal generation circuit (1), the camera signal (b) processed by the camera signal processing circuit (3b) is converted into an output video signal (e) as shown in FIG. is output as

Here, when the playback (PB) button is pressed, the VT
At the same time as the R section (21) enters the operating state, the vertical synchronization signal (g) of the synchronization signal generation circuit (1) is selected by the first changeover switch (22), and the phase comparison circuit (1) is selected as a reference signal.
1) is input. For this reason, the operation of the motor control circuit and the drum motor are driven in synchronization with the vertical synchronization signal (g) of the camera unit (20), so the magnetic heads (6a) and (6b) extract data from the magnetic tape (5). and selector switch (
14) and processed by the video signal processing circuit (15), the reproduced signal (C) shown in FIG. 2 is obtained. That is, the positions of the vertical synchronization signals of the camera signal (b) and the reproduced signal (c) are almost the same.

At this time, as shown in Fig. 1, the vertical synchronization signal (g) from the synchronization signal generation circuit (1) is input to the reference oscillator (12) of the VTR section (21), and initialization is performed. . That is, synchronization is achieved with the vertical synchronization signal (g).

Then, when the playback signal (C) becomes normal, that is, when the video playback starts, the changeover switch (16) is switched from the camera signal (b) by the output changeover signal (d) from the system controller (17). Playback signal (c
).

Therefore, as shown in the circle D of the output video signal (e) in Fig. 2, the vertical synchronization signal has a good connection even in the switching part from the camera signal (b) to the playback signal (c). becomes.

The control system of the drum motor (9) including the phase comparator circuit (11) is synchronized by the vertical synchronization signal using the reference oscillator ( 12), the reference oscillator (12) synchronizes with the vertical synchronization signal (g
), the transition is smooth.

Next, in the videotape playback state, as shown in FIG. 1, the reference oscillator (
12) is selected and the reference signal from the phase comparator circuit (11
), and in synchronization with the reference signal, the motor control circuit (10), drum motor (9) and rotating drum (7)
) to work.

This allows the magnetic tape (5) to be moved from the magnetic head (6a).
The recorded signal extracted by (6b) is processed by the video signal processing circuit (15) via the changeover switch (14) to become a reproduced signal (c) as shown in FIG. (16) and becomes the output video signal (e).

Here, when the stop button (19) in Fig. 1 is pressed, the second selector switch (23) selects the reference signal of the reference oscillator (12) in response to a command from the system controller (17) and outputs the synchronization signal. Send to generation circuit (1).

In this synchronization signal generation circuit (1), the solid-state image sensor (2) is driven by a drive circuit (3a) to extract an electrical signal so as to create a camera signal synchronized with the reference signal, and the camera signal is Processed by a processing circuit (3b).

Camera signal (b) output from this camera section (20)
When the system controller (17) becomes normal,
The changeover switch (16) is switched by the changeover signal (d) from the output video signal (e), and the output video signal (e) is switched from the playback signal (C) to the camera signal (b), which becomes the output video signal (e).

The state of the output video signal (e) at the time of this switching is shown in circle E in Figure 3, and in the switching part between the playback signal (c) and camera signal (b), the connection of the vertical synchronization signal is In good condition.

Note that the synchronization signal generation circuit (1) generates a reproduced signal (C).
After a predetermined period of time has elapsed, a transition is made from external synchronization using the reference signal to internal synchronization.

At this time, the external synchronization applies a trigger at the initial stage of the vertical synchronization signal, and the internal synchronization simply shifts from the triggered operating state to the synchronization signal generation circuit (1)'s own clock operation, resulting in a smooth transition. It is possible to transition from external synchronization to internal synchronization.

〔Effect of the invention〕

As explained above, the video recording and reproducing apparatus according to the present invention, when switching from camera input to videotape playback and from videotape playback to camera input, performs vertical synchronization of the camera manual signal or videotape playback signal before switching, respectively. Since the signal is synchronized with the vertical synchronization signal of the videotape playback signal or camera input signal to be switched, the output video signal at the time of transition from camera input to videotape playback and from videotape playback to camera input is It is possible to improve the connection of vertical synchronization signals.

Therefore, signals can be switched without synchronizing the display screen or disturbing the screen.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram showing one embodiment of the present invention, and FIG.
The figure is a waveform diagram for switching from a camera signal to a reproduction signal in one embodiment, FIG. 3 is a waveform diagram for switching from a reproduction signal to a camera signal in one embodiment, FIG. 4 is a block diagram of the configuration of a conventional example, and FIG. 5 6 is a waveform diagram for switching from a conventional camera signal to a reproduction signal, and FIG. 6 is a waveform diagram for switching from a conventional reproduction signal to a camera signal. In the figure, (1) is a synchronization signal generation circuit, (2) is a solid-state image sensor, (3) is a conversion means, (3a) is a drive circuit, (
3b) is a camera signal processing circuit (4) is a lens, (5) is a magnetic tape, (6a), (6b) is a magnetic head, (
7) is a rotating drum, (8) is a rotating pulse generator, (9)
is the drum motor, (10) is the motor control circuit, (11)
is a phase comparison circuit, (12) is a reference oscillator, (13) is a waveform shaping circuit, (14) is a changeover switch, (15) is a video signal processing circuit, (16) is a changeover switch, (17) is a system controller, ( 18) is the play button, (19)
is a stop button, (20) is a camera section, (21) is a video tape recorder section (VTR section), (22) is a first changeover switch, (23) is a second changeover switch, (24)
) is an external synchronization input terminal. In the figures, the same symbols indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] A camera unit that converts an optical image signal of a subject into a camera signal based on a synchronization signal generated by a synchronization signal generation circuit and outputs the camera signal; and a camera unit that converts the camera signal from the camera unit into a magnetic tape. a VTR unit comprising a recording means, which reads video information recorded on the magnetic tape based on a reference signal generated by a reference signal oscillator, converts it into a video signal, and outputs it; and the camera signal and the video signal. and a selection means for switching and selecting between the two and outputting the selected signal to the outside as an output video signal, and the camera section is configured to convert the reference signal into the synchronization signal before switching the output video signal from the video signal to the camera signal. a first signal switching means for externally synchronizing by replacing the camera signal with the video signal for a predetermined period of time, and the VTR section converts the synchronization signal into the reference signal before switching the output video signal from the camera signal to the video signal. Instead, it has a second signal switching means that externally synchronizes by replacing it for a predetermined time, and is characterized in that when switching the output video signal, the signal after switching is synchronized with the signal before switching, and then the switching of the output video signal is performed. Video recording and playback device.