JPH05103253A - Video camera - Google Patents

Abstract

PURPOSE:To set a shutter speed to be longer than 1/60 seconds, and to obtain a smooth video. CONSTITUTION:At the time of setting the shutter speed of an image pickup element 1 to be longer than 1/60 seconds, the shutter speed is fixed to be 1/60 seconds, and transmitted to an A/D converter 2 at every 1/60 seconds. A digital video signal obtained by the A/D converter 2 is transmitted through (n) pieces of adders 3-1 to 3-n in parallel to (n) pieces of video memories 4-1 to 4-n, and added to the digital video signal held at present in each video memory 4-1 to 4-n. On the other hand. it is necessary to transmit the digital video from an output video switching circuit 5 to a D/A converter 6 at every 1/60 seconds, and the digital video signal is successively read out from each video memory 4-1 to 4-n at 1/60 second interval, and simultaneously the data in the video memories 4-1 to 4-n after the read out are erased.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a shutter speed
It relates to a video camera that can be set longer than 1/60 seconds.

[0002]

2. Description of the Related Art In a conventional video camera, as shown in FIG. 4, the shutter speed of an image pickup device 11 in the video camera is set longer than 1/60 seconds, and the obtained video signal is digitalized by an A / D converter 12. After being converted into a signal, it is stored in the video memory 14. At this time, the number of times that the image signal is sent from the image pickup device 11 by the control signal of the output video switching circuit 15 is less than 60 times per second, and thus the signal stored in the video memory 14 is different from that of the output video switching circuit 15. By control signal
It is repeatedly sent to the video tape recorder through the D / A converter 16 every 1/60 seconds.

[0003]

In such a conventional structure, since the image signal obtained from the image pickup device 11 is less than 60 screens per second, the same screen is continuously output a plurality of times. Therefore, an image obtained with a fast moving image is not smooth.

The present invention solves the above problems and provides a video camera in which the shutter speed of the video camera can be set longer than 1/60 seconds, and the movement of the obtained image can be smoothed. Has a purpose.

[0005]

In order to solve the above problems, a video camera of the present invention comprises an image pickup device and an A / D for converting a video signal from the image pickup device into a digital video signal.
A converter, a plurality of video memories for storing digital video signals, a digital video signal of the video memory and the A
A plurality of adders for adding the digital video signals from the D / D converter and one by one to the plurality of video memories are sequentially selected, and the data of one selected video memory is output as a digital video signal, and immediately after that An output video switching circuit for erasing data in one video memory and a D / A converter for converting a digital video signal from the output video switching circuit into a video signal are provided.

[0006]

With the above structure, a video memory capable of storing video signals for a plurality of screens is used, and a digital video signal adder is added to each video memory, thereby reducing the shutter speed of the video camera to 1/60 second. It can be set to an integral multiple, and the motion of the resulting image can be smoothed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram showing an embodiment of a video camera of the present invention. In FIG. 1, the shutter speed of the image sensor 1 is fixed to 1/60 second even when it is desired to be longer than 1/60 second, and is sent to the A / D converter 2 every 1/60 second. The digital video signals obtained by the A / D converter 2 are sent in parallel to the video memories 4-1 to 4-n through the n adders 3-1 to 3-n, respectively, and the respective video memories 4-1 are sent. For signals 4-n, the signal of the A / D converter 2 is added to the currently held digital video signal and stored. On the other hand, since it is necessary to send a digital image from the output image switching circuit 5 to the D / A converter 6 every 1/60 seconds, 1/60 from each of the image memories 4-1 to 4-n.
At the same time, the digital video signals are sequentially read out at a time interval, and at the same time, the data in the video memories 4-1 to 4-n after the reading are erased.

An outline of this operation is shown in FIG. 1/60 on the horizontal axis
Taking the time in seconds, the images taken by the image pickup device at each time are conveniently ..., t-n + 1, ..., t-2,
t-1, t, t + 1, t + 2, ..., t + n-1, t +
n, t + n + 1, ... At each time, the images of the respective image memories 4-1 to 4-n, the image memory selected by the output image switching circuit 5 and the selected image signal are also shown.

By such an operation, the read digital video signal is always a video of n / 60 seconds, and a slow shutter video of n / 60 seconds can be obtained. Moreover, when comparing one frame and the next frame, as is clear from FIG. 2, (n-1) / 60 seconds are video signals at the same time, and video signals at different times are only 1/60 seconds. , The difference between each frame is reduced, and smooth moving images can be obtained.
Also, the minimum illuminance as a video camera at this time is 1/60
It is 1 / n of a second, and high-sensitivity shooting is possible.

FIG. 3 is a schematic block diagram showing a concrete embodiment of the present invention. 6 screens of video memory 41, 42, 43, 44 that can be added by adders 31, 32, 33, 34, 35, 36
By preparing 45 and 46, a slow shutter of 1/10 (6/60) seconds can be realized and smooth movement can be obtained. In addition, the minimum illuminance of the video camera at this time is ⅙ of the 1/60 second, and high-sensitivity shooting is possible.

[0011]

As described above, according to the present invention, the shutter speed of the video camera can be set to be longer than 1/60 second, and the motion of the obtained image can be smoothed.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram showing a processed image of each unit during operation of the video camera of the present invention.

FIG. 3 is a schematic block diagram showing a specific embodiment of the video camera of the present invention.

FIG. 4 is a schematic diagram showing a conventional video camera.

[Explanation of symbols]

 1 Image sensor 2 A / D converter 3-1 to 3-n Adder 4-1 to 4-n Video memory 5 Output video switching circuit 6 D / A converter

Claims (1)

[Claims] 1. An image sensor, and an A / D converter for converting a video signal from the image sensor into a digital video signal,
A plurality of video memories for storing digital video signals, a plurality of adders for adding the digital video signals of the video memories and the digital video signals from the A / D converter, and one for each of the plurality of video memories An output video switching circuit for outputting data of the selected one selected video memory as a digital video signal and immediately thereafter deleting the data of the one video memory, and a digital video signal from the output video switching circuit Video camera equipped with a D / A converter to convert to.