JPS6320073B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A system for creating a composite image using a VTR (video tape recorder) and a camera is known.

For example, what is called a chromakey device obtains a playback signal for a background image from a VTR, and an imaging signal for a subject such as a person from a camera, and synthesizes the two to produce a picture of a subject such as a person in the background. It is used to fit a statue.

By the way, when compositing a subject image into the background in this way, if the contents of the background change, for example, the perspective changes, the composite image may become unnatural unless the size of the subject image is changed. . The size of this subject image can be changed by performing a zooming operation on the lens of the camera, but conventionally, the zooming operation of this camera was
This is done manually while monitoring the monitor image of the playback signal from the VTR.

However, while monitoring the monitor image,
Manually zoom the camera lens on the VTR
It was very difficult to follow the content of the reproduced video.

In consideration of this point, this invention allows the camera lens to zoom according to the content of the video being played back on the VTR.
The aim is to provide something that automatically follows the content of the video being played back on the VTR.

Hereinafter, an example of a video synthesis device according to the present invention will be explained with reference to the drawings.

Figure 1 shows an example of the case where the present invention is applied to the above-mentioned chromakey device. In this example, a subject image from a camera is synthesized during playback of a VTR, and this is recorded on another VTR. There is.

That is, in FIG. 1, 1 and 2 are VTRs, and 3 is a camera.

A tape on which a background image is recorded is loaded into the VTR 1, and the VTR 1 is put into playback mode. In this case, a key code is inserted into the vertical blanking section V _BL of the video signal recorded on this tape in accordance with the contents such as the perspective of the background image.

A subject such as a person to be inserted into the background image is imaged by the camera 3 with one side of the subject being almost uniformly blue in the background.

The reproduced signal from the VTR 1 is supplied to one input terminal of the switch circuit 4. Further, the image signal from the camera 3 is supplied to the encoder 6 through the camera control unit 5 and converted into an NTSC color video signal, which is then sent to the switch circuit 4.
is supplied to the other input end of the .

The signal from the camera 3 is also transmitted to the blue color detection circuit 7.
The blue hue component of the imaging signal is detected, and the detection output is supplied to the switching pulse forming circuit 8, and only the image section consisting of only the blue hue of the image captured by the camera 3 is processed. 0"
A switching pulse SW is obtained from this, and the switching circuit 4 is switched by this pulse SW.

That is, since the subject is imaged with a blue background, when the camera 3 is imaging this blue background, this is detected by the blue detection circuit 7, the pulse SW becomes "0", and the switch circuit 4 is It is switched to the state shown in the figure, and the switch circuit 4
The playback signal of VTR1 is extracted. When the camera 3 is photographing a subject such as a person,
Since no blue detection output is obtained, the pulse SW becomes "1", the switch circuit 4 is switched to a state opposite to that shown in the figure, and the image signal of the subject from the encoder 6 is obtained from the switch circuit 4.

Therefore, the output signal of the switch circuit 4 is transferred to the VTR 2.
When the reproduced image is viewed on the monitor receiver 9, the monitor receiver 9 displays a composite image in which the image of the subject, such as a person, captured by the camera 3 is embedded in the background image from the VTR 1. It will be projected. Incidentally, if there is no need to record a composite image and only a composite image is to be obtained, the output of the switch circuit 4 may be directly supplied to the monitor receiver 10 as shown in the figure.

In this way, a composite image is obtained in which a subject image such as a person is embedded in the background image, but the key code signal included in the playback video signal of the VTR 1 is used to zoom the camera lens according to changes in the background. This is done as follows.

That is, the reproduction signal of the VTR 1 is supplied to the key code detection and decoding circuit 11. In this key code detection and decoding circuit 11,
The reproduction signal of the VTR 1 is supplied to the gate circuit 14 and also to the vertical synchronization signal separation circuit 12, where the vertical synchronization signal P _V (FIG. 2A) is extracted.
For example, the monostable multivibrator 13 is triggered by the trailing edge of this vertical synchronization signal P _V , and the key code signal of the vertical blanking section V _BL of the video signal is generated.
Section "1" corresponding to the section where C _K is inserted
A gate pulse G _P (FIG. 2B) is obtained, which is supplied to the gate circuit 14. Then, this gate circuit 14 is turned on in the section where the gate pulse G _P is "1", and from this, the key code signal C _K (Fig. 2C) inserted in the vertical blanking section is obtained. The signal is supplied to the digital-to-analog converter 15, from which a pulse voltage E _A (FIG. 2D) having a peak value corresponding to the code information is obtained. Then, this pulse voltage is applied to the peak hold circuit 16.
From this, a voltage E _H (Fig. 2 E) that holds the pulse voltage E _A for one field period is obtained, and this is supplied to the motor 18 that controls the rotation amount of the zoom ring 19 through the drive circuit 17. The motor 18 is controlled to rotate by an amount corresponding to the voltage value.

In this case, the key code signal C _K inserted into the vertical retrace section V _BL corresponds to the distance, etc. of the background image, so the camera 3
This means that the size of the subject image will change depending on the background image, and the composite image will no longer look unnatural.

FIG. 3 shows another example of the device of this invention, which is a so-called dissolve device.

That is, in this example, the reproduction signal from the VTR 1 and the imaging signal from the encoder 6 are supplied to the resolve circuit 20, and the two signals are superimposed.

In this resolve circuit 20, it is also possible to manually vary the ratio of the amount of superposition of both signals.
In this example, the key code signal C _K
In addition, a key code for controlling the overlapping ratio is recorded, and by this, the amount of overlapping is automatically controlled in accordance with the video content of the reproduction signal from the VTR 1.

In this example as well, the key code signal C _K in the VTR playback signal allows the zooming of the camera 3 to be changed depending on the video content of the VTR playback signal.

In this way, according to the video synthesis device of the present invention, when compositing an image captured from a camera with a reproduced image of a VTR, the camera lens is automatically zoomed according to the contents of the reproduced image of the VTR. is performed, resulting in a natural-looking composite image.

It should be noted that the device of the present invention is of course applicable not only to the above-mentioned example but also to other image synthesis techniques such as a wiper.

Note that the key code signal can be recorded not only for zooming control of the camera and for controlling the resolve circuit as in the above example, but also for controlling the VTR 2.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an example of the video synthesis apparatus according to the present invention, FIG. 2 is a diagram for explaining the same, and FIG. 3 is a system diagram of another example of the apparatus of the invention. 1 is a VTR, 3 is a camera, 4 is a switch circuit,
11 is a key code detection circuit, and 19 is a zoom ring.

Claims (1)

[Claims] 1. (a) A recording and reproducing device that outputs a first video signal recorded with a code signal corresponding to the amount of zooming inserted in advance into a vertical blanking period, and (b) a motor that performs zooming. (c) code signal detection means for detecting the code signal; (d) detecting a predetermined hue of the background image from the second video signal; A switching circuit that switches between the first video signal and the second video signal, or a mixing circuit that mixes the first video signal and the second video signal in accordance with the first video signal. (e) controlling the motor based on the output signal of the code signal detection means to change the size of the subject image of the second video signal in accordance with the zooming amount of the first video signal; and the above two video signals are synthesized on screen using the switching circuit or the mixing circuit.