JPH0287875A - Erroneous picture recording preventing device for video camera - Google Patents

Abstract

PURPOSE:To automatically release a picture recording state, when a video camera is left unused or put away in a state that it is forgotten to switch off a picture recording switch by stopping the picture recording state, when it is decided that an image pickup screen is not varied. CONSTITUTION:A signal from a CCD 1 driven by a driver 3 is processed by a signal processing circuit 2, and a signal 13 which turns ON in only the n-th frame signal period and a signal 14 which turns ON in only the (n+1)-th frame signal period are fetched by switches 6, 7 from a luminance signal 5. Subsequently, the signals are converted to DC voltages by integration circuits 8, 9, its difference voltage (V0) 11 is derived by an operational amplifier 10, and the variation of an image pickup screen is decided. In such a manner, when it is decided that the image pickup screen is not varied, the picture recording state of a video camera is stopped. Therefore, erroneous picture recording caused by forgetting to switch off a picture recording switch is prevented, and it can be realized to use efficiently a picture recording tape and a battery.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for preventing accidental recording of a video camera, and in particular, a device for automatically changing the recording state when the video camera is left unattended or put away due to forgetting to turn off the recording switch. The present invention relates to an accidental recording prevention device for a video camera having a release function.

[Traditional techniques, techniques]

Conventionally, there is no video camera that has a function of automatically canceling this type of recording state, and the mechanism is limited to displaying operating states such as recording and stopping using an LED, liquid crystal, etc. on the viewfinder or the video camera body.

[Problem to be solved by the invention]

The conventional video cameras mentioned above do not realize that they have forgotten to turn off the recording switch unless the user looks at the video camera's display (viewfinder or main unit), and the state of erroneous recording continues. The disadvantage is that it wastes battery power.

An object of the present invention is to provide a video camera erroneous recording prevention device that prevents erroneous recording caused by forgetting to turn off the recording switch.

[Means to solve the problem]

The video camera erroneous recording prevention device of the present invention includes means for detecting the state of a part or the entire imaging screen, means for determining whether the imaging screen has not changed based on the detected information, and an output of the determining means. and a means for stopping the recording state, and is configured to prevent erroneous recording.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a video camera erroneous recording prevention device for explaining a first embodiment of the present invention.

As shown in FIG. 1, this erroneous recording prevention device processes a signal from a CCD 1 driven by a driver 3 in a signal processing circuit 2, and transmits a luminance signal (hereinafter referred to as a Y signal) 5 to a switch 6.
Enter 7. The switch 6 receives a signal 13 from the timing circuit 4 connected to the driver 3 that turns on for the n-th frame signal period, and the switch 7 receives a signal 14 that turns on for the n-11th frame signal period. be done. The output of this switch 6.7 is converted into a DC voltage by an integrating circuit 8.9, and the difference voltage (
Vo) 11 is generated. Since this differential voltage (Vo) 11 is a differential voltage for each period of the frame signal, the amplitude of Vo represents the magnitude of change in the imaging screen. Therefore,
If the amplitude of Vo is small, it can be determined that the imaged object is not moving. Furthermore, if the amplitude of Vo continues to be small for a certain period of time, normally the image is not being photographed, but 1. Recording switch (not shown)
It can be determined that the lamp was left unattended because it had been forgotten to turn off. In FIG. 1, a comparator 15 compares Vo through the full-wave rectifier circuit 12 and a reference voltage (Vref) 16, and the timer 1
If it continues for more than the time set in step 8, one control signal will be output,
Stop the recording status of the video camera.

FIG. 2 is a block diagram of a video camera erroneous recording prevention device for explaining a second embodiment of the present invention.

As shown in Fig. 2, in this embodiment, the imaging screen is divided into several parts, changes in the imaging screen are detected for each divided screen, and the detection accuracy is improved by calculating the logical sum of the respective detection outputs. It is something.

This erroneous recording prevention device includes a CCD 1 and a signal processing circuit 2. COD driver 3. The timing circuit 4 and timer 18 are the same as in the first embodiment described above. The operation of this prevention device is to pass the Y signal output from the signal processing circuit 2 to the judgment circuits 27 and 281 according to the split screen.
~28. The respective outputs are logically summed by an OR gate 20, and a control output 19 is output from a timer 18. These judgment circuits 27.28r-28. In this operation, the Y signal is input to the sample/hold circuit (S/H) 21, and a signal corresponding to the Y signal for each frame is output under control from the timing circuit 4. Next, the S/H 21 output signal is transferred to two types of peak hold circuits 22 (+ and -).
．． 23 to hold the peak, and then input it to operational amplifier 2.
Then, the output of the operational amplifier 24 is compared with a reference voltage (Vref) 26 by a comparator 25 to generate an output signal for each judgment circuit.

〔Effect of the invention〕

As described above, the apparatus for preventing erroneous recording of a video camera according to the present invention includes means for detecting the state of the photographing screen, means for determining whether the photographing screen has not changed based on the detected information, and the determining means. By having a means for stopping the recording state of the video camera by the output of , it is possible to prevent erroneous recording due to forgetting to turn off the recording switch, and to realize efficient use of the recording tape and battery.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a video camera erroneous recording prevention device for explaining a first embodiment of the present invention, and FIG. 2 is a block diagram of a video camera erroneous recording prevention device for explaining a second embodiment of the present invention. It is a block diagram of a prevention device. 1... CCD image sensor, 2... signal processing circuit, 3.
...COD driver, 4...timing circuit, 5...
・Brightness signal, 6.7... Switch, 8.9... Integrating circuit, 10.24... Operational amplifier, 11... Operational amplifier output voltage, 12... Full wave rectifier circuit, 13.・・n
14th frame signal period, 14... n+1th frame signal period, 15.25... comparator, 16.26.
...Reference voltage, 17...Comparator output, 18...Timer, 19...Control signal, 20...OR gate, 2
1... Sample hold circuit, 22.23... Peak hold circuit, 27.28+~28. ...judgment circuit.

Claims (1)

[Claims] means for detecting the state of a part or the entire imaging screen;
The video camera is characterized in that it has means for determining whether the imaging screen has not changed based on detected information, and means for stopping the recording state based on the output of the determining means, to prevent erroneous recording. Recording prevention device.