JPH0446508B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a stereoscopic video signal generation device used in a stereoscopic video reproduction system.

<Summary of the Invention> The present invention alternately switches and outputs left and right video signals obtained by imaging a subject with binocular parallax for each field, and reproduces a video based on the left and right video signals. Regarding a stereoscopic image playback system that reproduces a stereoscopic image by viewing the left and right images through shutters that are alternately projected on a screen and alternately opened and closed in accordance with the left and right images, it is particularly important to maintain a constant synchronization peak level. The system is designed to alternately obtain left and right video signals.

<Prior Art> FIG. 3 shows a block diagram of a three-dimensional video reproduction system that has been generally employed in the past.

Here, 1R and 1L are two left and right imaging television cameras arranged with left and right binocular parallax θ with respect to the subject 2 and driven synchronously in phase lock with each other (hereinafter 1R is the right camera and 1L is the left camera). A right-side video signal is obtained from the right-side camera 1R, and a left-side video signal is obtained from the left-side camera 1L. These left and right video signals are alternately switched for each field by a switch (analog switch) 3, and are supplied as a stereoscopic video signal to a CRT display device 5, such as an ordinary television receiver. Reference numeral 4 denotes a field signal generation circuit, in which a field signal is generated based on the vertical synchronization signal in the left video signal obtained from the left camera 1L, and the switch 3 switches each field based on the field signal. Driven. On the other hand, the field signal is also supplied to the shutter drive circuit 6, and the shutter drive pulses obtained from the circuit 6 drive a pair of left and right electro-optical shutters (for example, liquid crystal shutters) 7R and 7L to open and close for each field. .

To explain the above operation in more detail using FIG. 4, the right camera 1R now outputs a right video signal as shown in FIG. 4a, and the left camera 1L outputs a right video signal as shown in FIG. 4b. When the left video signal is output (of course in this case both cameras 1
R and 1L are driven synchronously, so the synchronization phases of the video signals match), and the left and right video signals are alternately switched for each field by the switching operation of switch 3, as shown in Figure 4c. A stereoscopic video signal is supplied to the display device 5, and at this time, a right-side video and a left-side video are alternately displayed on the video playback screen of the display device 5. Now, while the right image is being displayed on the screen, the right shutter 7R is in the open state and the left shutter 7L is in the closed state in synchronization with this, as shown in Fig. 4d and e. Therefore, the image on the right side is recognized only by the right eye. Similarly, while the left image is displayed on the screen, the right shutter 7R is closed, the left shutter 7L is closed, and the left image is recognized only by the left eye. As a result, the image displayed on the screen is perceived to have a three-dimensional effect.

<Problems to be Solved by the Invention> However, in the conventional stereoscopic video reproduction system as described above, the brightness of the subject 2 imaged by the left camera 1L and the brightness of the subject 2 imaged by the left camera 1R are different. If the values are different,
Since the APL (average video level) of the right video signal and the left video signal obtained from the left and right cameras 1L and 1R are different as shown in Figure 2 a and b, switch 3
As shown in FIG. 2c, the stereoscopic video signal obtained through the 3D video signal has a synchronization peak level that changes for each field. Therefore, when such a stereoscopic video signal is applied to the display device 5, the display device 5
There was a risk that the synchronization would become unstable.

<Means for Solving the Problems> The present invention has been made in view of the above points, and in a stereoscopic video signal generation device of a conventional stereoscopic video playback system, the two cameras 1L and 1R on the left and right
A peak value clamping means is provided for clamping the synchronized peak value levels of the left and right video signals imaged at the same potential level.

<Function> In this case, even if the brightness of the subject imaged by the two left and right cameras differs considerably, the synchronization peak level of the stereoscopic video signal supplied to the display device is always constant, and stable synchronization operation can be achieved. It will be done.

<Example> The present invention will be described below according to an example shown in the drawings. FIG. 1 shows an embodiment of a three-dimensional video reproduction system employing the present invention, in which the same parts as those of the conventional example shown in FIG. 3 are given the same reference numerals. That is, here 1R is the right camera, 1L is the left camera, 3
is a switch, 4 is a field signal generation circuit, 5 is a display device, 6 is a shutter drive circuit, 7R
7L is the right shutter, and 7L is the left shutter, which are not particularly different from the conventional example shown in FIG.

Here, especially the right camera 1R and the left camera 1
Peak value clamp circuits 8R and 8L are inserted between L and switch 3, respectively.

As mentioned above, two peak value clamp circuits 8R,
8L, the brightness of the subject 2 imaged by the left camera 1L and the right camera 1
Even when the brightness of the subject 2 imaged by R is different and the APL of the left and right video signals obtained from the left and right cameras 1L and 1R are different as shown in Figure 2 a and b, each video signal is The peak value clamping circuits 8L and 8R clamp the synchronous peak value levels to the same DC potential level (for example, zero potential), and as a result, the synchronous peak value level of the stereoscopic video signal obtained via the switch 3 is always constant as shown in FIG. 2d.

The stereoscopic video signal thus obtained is supplied to the display device 5, and the right-side video and left-side video are alternately displayed on the video playback screen. While the right image is displayed on the screen, the right shutter 7R is opened and the left shutter 7L is synchronized, and the right image is recognized only by the right eye, and the left image is displayed on the screen. While the display is displayed, the left shutter 7L is open and the right shutter 7L is open.
R is in the closed state, and the left image is recognized only by the left eye. As a result, the image displayed on the screen can be perceived with a three-dimensional effect.

<Effects of the Invention> As described above, according to the stereoscopic video signal generation device of the present invention, after clamping the synchronous peak level of each video signal imaged by the left and right cameras to the same DC potential level, Since the output is switched alternately for each field, even if the brightness of the subject imaged by the left and right cameras differs, it is possible to always obtain a 3D video signal with a constant synchronized peak level. The synchronization of display devices does not become unstable as in the past.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a stereoscopic video reproduction system employing the device of the present invention, FIG. 2 is a signal waveform diagram for explaining the operation of the same device, FIG. 3 is a block diagram of a conventional stereoscopic video reproduction system, and FIG. The figure is a signal waveform diagram for explaining the operation of the system. 1R...right camera, 1L...left camera, 2...subject, 3...switch, 4...field signal, generation circuit, 5...display device, 6...shutter drive circuit, 7R...right shutter, 7L...left shutter.

Claims (1)

[Claims] 1. Left and right video signals obtained by imaging a subject with left and right binocular parallax are alternately switched and output for each field, and a video based on the left and right video signals is displayed on a video playback screen. In a stereoscopic image playback system that reproduces a stereoscopic image by viewing the left and right images through shutters that are alternately projected on the top and opened and closed alternately in response to the left and right images, the left and right images are arranged with binocular parallax. and two left and right imaging means that are synchronously driven in phase lock with each other, and a peak that clamps the synchronized peak value level of each of the left and right video signals imaged by each of the imaging means to the same DC potential level. and a video signal switching means that alternately switches and outputs the left and right video signals obtained from the respective clamping means for each field, and alternately outputs the left and right video signals having a constant synchronized peak value level. A stereoscopic video signal generation device characterized in that it obtains a stereoscopic video signal.