JPH0454090A - Video recording method by cordless unattended diving device - Google Patents

Abstract

PURPOSE:To record only a desired video image accurately and sharply by outputting a video recording start stop signal to a changeover circuit synchronously with a time when a picture signal the same picture signal displayed on a monitor is outputted from a picture memory while a command signal is given so as to operate/stop a video recorder. CONSTITUTION:A supervisor (not shown) on a control vessel 12 always monitors a video image on a video monitor 24 and turns on a recording start switch (not shown) of a command device 32 of a video remote controller 30 when a picture requiring recording is displayed. When the video recording start signal is received by a receiver 40, the signal is given to a time reference circuit 46 via a filter amplifier 42 and a demodulator 44. An output signal of the time reference circuit 46 is outputted when the recording start switch 32 is closed synchronously with a time when a color signal inputted to a picture memory 28 is outputted from the picture memory 28 simultaneously with the picture displayed on the video monitor 24. Then a changeover circuit 29 is closed and the video recorder 48 starts recording.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a video recording method that allows color images taken by an unmanned underwater vehicle that is remotely controlled by sound to be captured into a recording device by remote control. It is.

[Conventional technology]

Recently, remote-controlled unmanned underwater vehicles have been developed and put into practical use for exploration of the ocean floor and underwater work. These unmanned underwater vehicles have usefulness different from manned vehicles, such as requiring significantly less water pressure countermeasures than manned vehicles, being easier to make smaller and lighter, and being cost-effective.

By the way, unmanned underwater vehicles (hereinafter referred to as FSV), which are remotely controlled via acoustic radio, can currently be monitored using monitoring equipment capable of transmitting rough monochrome still images in 2 to 3 seconds. It is limited to being able to mount commercial units. At the research level, it has become possible to transmit relatively detailed still images in color at a rate of one every seven seconds from a distance of 3,500 meters.

[Problems to be Solved by the Invention] However, it is often important to obtain detailed color images not only in academic and technical fields but also in news reporting. Therefore, it is preferable to use a cabled unmanned submersible that can be precisely controlled and send color images, but in dangerous waters or places where there is a risk of cables getting tangled, it is necessary to use FSV. There's a problem.

As a countermeasure, a color video camera is mounted on the FSV. Conventionally, color images can only be recorded by randomly recording consecutive images using a certain program. However, with this method, there is a risk of not being able to properly record important images, and
Since the capacity of the image recording device is limited, when cruising for the purpose of recording images, there is a problem in that the cruising time is limited by the capacity of the recording device.

Therefore, the present invention records only necessary images on the recording device installed in the FSV, and uses a device with a smaller storage capacity to record detailed color images on a small FSV. The object of the present invention is to provide an FSV video recording method that allows the maximum flight time to be obtained within the available recording capacity.

(Means for Solving the Problems) The configuration of the video recording method for an unmanned underwater vehicle according to the present invention to achieve the above object is to simultaneously output a color video signal and a monochrome video signal to the unmanned underwater vehicle. A video camera is installed to convert the monochrome video signal into an audio signal and send it to the command ship, and the color video signal is input to the image memory and temporarily stored, and then output to the input +11fi switching circuit, and the command ship: The submersible includes means for monitoring the monochrome video signal and means for transmitting an operation/stop command signal for the recording device, and the submersible applies the received command signal to a time reference circuit so that the command signal is issued. When the same image signal as the image displayed on the monitor is output from the image memory, a recording start/stop signal is output to the switching circuit to start/stop the recording device. be.

The monochrome image signal may be a signal from a monochrome video camera, or may be a signal obtained by converting a color signal from a color video camera into a monochrome signal.

However, in reality, the frequency band given to the color luminance signal is smaller than the band of the monochrome image signal, so the image quality deteriorates. Therefore, in consideration of image deterioration due to audiovisual transmission, a dedicated monochrome image signal is better.

Further, the monochrome image may be a quasi-moving image using frame-by-frame images. However, it is more preferable if the video is a continuous video.

〔Example〕

Hereinafter, F of the present invention will be explained with reference to the block circuit diagram shown in the attached figure.
The SV video recording method will be specifically explained.

In the figure, in the FSVI, a signal from a monochrome CCD video camera 2 is input to an image memory 4 for temporary storage, output as an image signal constituting one screen as a frame advance image, and modulated by a modulator 6 according to a carrier frequency. Shi, increase @
(amplifier 8) transmits the acoustic signal from the transmitter 10 to the command ship 12.
It transmits waves in the same manner.

When the transfer unit 14 of the command ship 12 receives the acoustic signal, it is applied to the filter amplifier 16, the monochrome image signal is demodulated by the demodulator 18, and converted to the original image signal by the decoder 2o and stored in the image memory 22. The image is temporarily stored and displayed on the video monitor 24 as a frame-by-frame image.

The FSVI is equipped with a color CCD video camera 26 that captures the same image as the monochrome video camera 2, and the color image signal is applied to an image memory 28 that temporarily stores the signal, and after storing the image signal for a predetermined period of time. ,
It is configured to sequentially output the signals to the switching circuit in the order of input.

On the command ship 12, a supervisor (not shown) constantly monitors the image on the video monitor 24, and when an image that requires recording appears, activates a recording start switch (not shown) on the command device 32 of the recording remote control device 30. When turned on, the signal is modulated into a transmission signal by the modulator 34, and amplified (amplifier 36).
After that, it is transmitted into the sea from the wave transmitter 38 as an acoustic signal.

When the receiver 40 receives the recording start signal, the signal is
The signal is applied to a time reference circuit 46 via a filter amplifier 42 and a demodulator 44. The output signal of the time reference circuit 46 is a color signal that is input to the image memory 28 at the same time as the image being displayed on the video monitor 24 when the recording start switch 32 is turned on. It is output synchronously with the timing. Then, the switching circuit 29 is turned on and the recording device 48 starts recording. The recording device 48 can use magnetic recording means such as a video deck.

Next, when the recording stop switch (not shown) of the command device 32 is turned on, the same image signal as the image displayed on the video monitor 24 is outputted from the image memory 28 through the same process as described above. The switching circuit 29 is turned off and image recording is stopped.

The storage capacity of the image memory 28 is determined by the time required for the monochrome image signal and command signal to propagate underwater, and the image reproduction time for displaying the image on a monitor. In other words, the speed at which sound travels underwater is approximately 1500 m/sec, so for example 3000 m/sec.
A case will be explained in which the capacity is determined so that images can be controlled even from a distance.

It takes approximately 2 seconds for an acoustic signal to propagate a distance of 3000 meters each way. Therefore, if the image playback time for displaying the image on the monitor, for example, 3 seconds, is added, the storage capacity needs to be sufficient to store the amount of images for about 10 seconds. Therefore, the time for turning on and off the switching circuit 29 changes depending on the distance, but this adjustment can be done by adding time information to the command signal using a distance measuring device provided in the command ship 12. The time reference circuit 46 may be equipped with an arithmetic function for adjusting the time output to the switching circuit 29 depending on the distance.

〔Effect of the invention〕

As explained above, the FSV video recording method of the present invention is as follows:
The FSV is equipped with a clear color recording device that monitors the image displayed on the monochrome monitor on the command ship.When an image to be recorded is displayed, a recording command is issued and the image is temporarily stored in the FSV. Since the system is configured so that the same image displayed on the monitor can be recorded from the color image displayed, only the desired image can be recorded accurately and clearly, and the waste of recording unnecessary images can be eliminated.

Therefore, necessary images can be effectively recorded with high quality images using a recording device with a more compact capacity, thereby dramatically improving the usefulness of highly mobile FSVs, especially small FSVs. I can do it.

[Brief explanation of the drawing]

The figure is a block circuit diagram for explaining the outline of a video recording device for an unmanned underwater vehicle according to the method of the present invention. ■...FSV (unmanned underwater vehicle), 2...monochrome video camera, 4, 22.28...image memory, 10.38...transmitter, 14.40...transfer device ,
24... Video monitor, 29... Switching circuit,
3o... Recording remote control device, 46... Time reference circuit, 48... Recording device.

Claims (1)

[Claims] The unmanned underwater vehicle is equipped with a video camera that simultaneously outputs color and monochrome video signals.The monochrome video signal is converted to an audio signal and sent to the command ship, and the color video signal is input to the image memory. After being temporarily stored, the signals are outputted to a switching circuit in the order of input, and the command ship is equipped with means for monitoring the monochrome video signal and means for transmitting an operation/stop command signal for the recording device, and the submersible is equipped with The command signal is applied to the time reference circuit, and the switching circuit starts and stops recording in synchronization with the timing when the same image signal as the image displayed on the monitor when the command signal is issued is output from the image memory. A video recording method for an unmanned underwater vehicle that outputs a signal to start and stop a recording device.