JP2522296Y2 - Video tape recorder device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a video tape recorder device suitable for application to, for example, a camera-integrated video tape recorder.

[Prior Art] Conventionally, for example, a camera-integrated video tape recorder having a recording check function is known.

That is, when the operation key for recording check is pressed in the recording standby mode, the video tape recorder performs reverse reproduction for a predetermined period and then performs normal reproduction. Then, a video signal reproduced by the video tape recorder is supplied to an image display device, for example, an electronic viewfinder, and a reproduced image is displayed. Thus, a recording check is performed.

[Problem to be Solved by the Invention] Here, at the time of reverse reproduction of a video tape recorder, a so-called noise bar appears in a reproduced image because a magnetic head scans across a recording track formed on a magnetic tape, which is very unsightly. Was something.

Therefore, the purpose of this invention is to make it easier to see the screen in the recording check mode.

Means for Solving the Problems The present invention is a video tape recorder device in which an input video signal is supplied as a recording signal to a video tape recorder through a signal processing circuit having an image memory,
Image display means for displaying an image based on the supplied video signal; and when the recording check mode is selected in the recording standby mode, the video tape recorder is set to the reverse playback state for a certain period and then to the normal reproduction state for a certain period and then to the recording standby. Video tape recorder control means for returning to the mode,
In the recording standby mode, the input video signal is sequentially updated and written in the image memory, and when the video tape recorder is in the reverse playback state, the video signal for one screen immediately before shifting from the recording standby mode to the recording check mode is transferred from the image memory. When the video tape recorder is in the reverse reproduction state, the video signal read from the image memory is supplied to the image display means, and when the video tape recorder is in the normal reproduction state, it is reproduced by the video tape recorder. Signal switching means for supplying a video signal to the image display means.

[Operation] In the above-described configuration, in the recording check mode, during the reverse playback period of the video tape recorder 20, the image memory 1
The video signal read from 4 and 24 is supplied to the image display device 28. That is, the image display device 28 displays a still image without a noise bar instead of a reproduced image with a noise bar.

[Embodiment] An embodiment of the present invention will be described below with reference to FIG. This example is an example applied to a camera-integrated video tape recorder.

In FIG. 1, reference numeral 1 denotes an image sensor, for example, a CCD solid-state image sensor. An image signal from the image sensor 1 is supplied to a process circuit 3 via an AGC amplifier 2, and the process circuit 3 outputs a luminance signal Y and a color difference signal. RY and BY are output.

An image signal from the image sensor 1 is supplied to a level detector 4, and the detection signal is supplied to an iris driver 5 as a control signal.
The iris 6 arranged on the front side of the image sensor 1 is driven. In this case, the opening of the iris 6 is controlled in accordance with the level of the imaging signal, and is controlled to be open at a recommended illuminance or less, for example, 200 lux or less.

The output signal of the AGC amplifier 2 is supplied to a level detector 7, and the detection signal is transmitted through the amplifier 8 to the AGC amplifier 2.
Is supplied as an AGC control signal. As a result, the AGC amplifier 2 operates below the recommended illuminance, and the level of the output signal of the AGC amplifier 2 is kept constant. 2a is a potentiometer for setting the maximum gain of the AGC amplifier 2.

The luminance signal Y output from the process circuit 3 is γ
The signal is supplied to an encoder 11 via a series circuit of a correction circuit 9 and an amplifier 10, and after a synchronization signal is added by the encoder 11, the signal is supplied to a fixed terminal on the R side of a changeover switch 12.

The output signal of the changeover switch 12 is supplied to an A / D converter 13, which converts the output signal into a digital signal, and then supplies the digital signal to a field memory 14 as a write signal.

The field memory 14 is controlled via a memory control circuit 15 by a controller 16 having a microcomputer. In this case, writing and reading are performed in parallel in the recording mode and the recording standby mode. In the recording check mode, only reading is performed during a reverse playback period of a video tape recorder described later, and writing and reading are performed in parallel during a normal playback period.

The controller 15 is connected with an operation key 17 for setting a recording check mode and an operation key 18 for setting a recording mode or a recording standby mode.

The output signal of the field memory 14 is supplied to the D / A converter 1
After being converted into an analog signal at 9, it is supplied as a recording signal to a VTR (video tape recorder) 20.

Further, the color difference signals RY,
B-Y is quadrature-modulated by the encoder 11 and then output as a color signal C (color subcarrier frequency is, for example, 3.58 MHz). The color signal C is supplied to the R-side fixed terminal of the changeover switch 21. You.

The output signal of the changeover switch 21 is supplied to an A / D converter 22 and is converted into a digital signal by the A / D converter 22, and then supplied to a color demodulation circuit 23. RY and BY are output in dot sequence.

The color difference signals RY and BY from the color demodulation circuit 23 are
It is supplied to the field memory 24 as a write signal.

This field memory 24 is also controlled by the controller 16 via the memory control circuit 15. In this case, writing and reading are performed in parallel in the recording mode and the recording standby mode. In the recording check mode, only reading is performed during a reverse playback period of a video tape recorder described later, and writing and reading are performed in parallel during a normal playback period.

The output signal of the field memory 24 is supplied to a color modulation circuit 25, and the color signal C output from the color modulation circuit 25 is
After being converted into an analog signal by the D / A converter 26, the analog signal is supplied to the VTR 20 as a recording signal.

The operation of the VTR 20 is controlled by the controller 16 via the VTR control circuit 27.

The luminance signal Y and the chrominance signal C output from the VTR 20 are supplied to P-side fixed terminals of the changeover switches 12 and 21, respectively. Switching of these changeover switches 12 and 21 is controlled by the controller 16. In this case, the mode is switched to the R side in the recording mode or the recording standby mode, and is switched to the P side in the recording check mode.

The output signal of the D / A converter 19 is supplied to an electronic viewfinder (EVF) 28, and the output signals of the D / A converters 19 and 26 are supplied to an adder 29, where they are added to each other. And supplied to the monitor connection terminal 31.

In the above configuration, in the recording standby mode,
The changeover switches 12 and 21 are connected to the R side, and writing and reading are performed in the field memories 14 and 24 in parallel. As a result, the subject currently being photographed is displayed on the EVF 28 (shown in FIG. 3A).

In this state, when the operation key 17 is pressed to set the recording check mode, the operation is performed as shown in FIG.

That is, when it is determined in step 41 that the operation key 17 has been pressed, in step 42, the field memories 14 and 24 are brought into a still image state. That is, the video signals of the last screen supplied from the video camera unit in the recording standby mode are repeatedly read from the field memories 14 and 24. As a result, the final screen is displayed as a still image on the EVF 28 (see FIG. B).

Then, in step 43, the VTR 20 is set to the reverse reproduction state, and at this time, the changeover switches 12 and 21 are switched to the P side.

Next, at step 44, it is determined whether or not two seconds have elapsed. When two seconds have elapsed, at step 45, the VTR 20 is set to the normal reproduction state.

Then, in step 46, the field memories 14 and 24
Is released. That is, these field memories 14 and 24 are set in a state where writing and reading are performed in parallel. As a result, the EVF28 has a VTR20
, An image based on the video signal reproduced, that is, a reproduced image is displayed (illustrated in FIG. C).

Next, in step 47, it is determined whether or not 2 seconds have elapsed. If 2 seconds have elapsed, in step 48, the mode is set to the recording standby mode, and the process returns to step 41. At this time, the changeover switches 12 and 21 are switched to the R side. As a result, the subject currently being photographed is displayed on the EVF 28 (illustrated in FIG. D).

Note that the two-second period in the above description is not limited to this.

FIG. 4 shows the operation of the VTR 20 in the recording check mode in relation to the head position on the magnetic tape. The contents in parentheses indicate the display contents on the EVF28.

Since the reproduced image during the normal reproduction start period is disturbed by the delay of the mechanical operation of the VTR 20, muting may be performed at this time, or the display of the still image may be extended.

As described above, according to the present example, the VT
During the period in which the R20 performs reverse playback, the EVF 28 displays a still image based on the video signal from the video camera unit. In other words, this
Since the EVF 28 displays a still image without a noise bar instead of a playback image with a noise bar, the screen in the recording check mode has the advantage of being very easy to see.

Although the case where the recording check is performed by the EVF 28 has been described above, a similar effect can be obtained when a monitor is connected to the monitor connection terminal 31 and the recording is checked using this monitor.

[Effects of the Invention] As described above, according to the invention, in the recording check mode, during the reverse playback period of the video tape recorder, the video signal read from the image memory is supplied to the image display device. Since a still image without a noise bar is displayed on the image display device instead of a reproduced image with a noise bar, there is an advantage that the screen in the recording check mode is very easy to see. When the normal reproduction period of the video tape recorder in the recording check mode ends, the mode automatically returns to the recording standby mode, so that the operation for shifting to the recording mode becomes easy.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing an operation in a recording check mode, FIG.
The figure shows the EVF display screen in the recording check mode,
FIG. 4 is a diagram showing the operation of the VTR in the recording check mode. DESCRIPTION OF SYMBOLS 1 ... Image sensor 2 ... AGC amplifier 3 ... Process circuit 4, 7 ... Level detector 6 ... Iris 11 ... Encoder 12, 21 ... Changeover switch 13, 22 ... A / D converter 14, 24… Field memory 15… Memory control circuit 16… Controller 17,18… Operation keys 19,26… D / A converter 20… VTR 27… VTR control circuit 28 …… Electronic viewfinder 29… … Adder 31 …… Monitor connection terminal

Claims (1)

(57) [Scope of request for utility model registration] 1. A video tape recorder device in which an input video signal is supplied as a recording signal to a video tape recorder through a signal processing circuit having an image memory, wherein an image display for displaying an image based on the supplied video signal is provided. Means, when the recording check mode is selected in the recording standby mode, a video tape recorder control means for returning the video tape recorder to the recording standby mode as the normal reproduction state for the predetermined period after the video tape recorder is set to the reverse reproduction state for the predetermined period. In the recording standby mode, the input video signal is sequentially updated and written in the image memory, and when the video tape recorder is in the reverse playback state, the image memory shifts from the recording standby mode to the recording check mode. Memory system that repeatedly reads the video signal for the immediately preceding screen Means for supplying a video signal read from the image memory to the image display means when the video tape recorder is in the reverse playback state, and the video tape recorder when the video tape recorder is in the normal playback state. And a signal switching means for supplying a video signal reproduced by the video display means to the image display means.