JP2514803B2 - Multi-screen display system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention divides and displays an image of one screen of an input video signal of a still image or a moving image on each of a plurality of display devices arranged vertically and horizontally. The present invention relates to a multi-screen display system in which the image of one screen is displayed on the entire plurality of displays.

[Prior Art] Conventionally, as a device which is displayed on a large screen to be shown to a large number of people, there is a movie device, a projection type projection device, or the like, and as is well known, the degree of stimulus given to the observer is high and the impression is large. So, movie screens and projection screens are getting huge. However, they require a large space and a device for enlarging an image, and it is difficult to obtain a high-quality image with a sufficient screen size due to cost constraints.

Therefore, an object of the present invention is to provide a multi-screen display system capable of obtaining a sufficient screen size and high-quality video without requiring a large-scale space and device.

[Means for Solving the Problems] The present invention made to solve the above problems is to divide and display one screen image of an input video signal on each of a plurality of display devices arranged vertically and horizontally. Thus, in the multi-screen display system in which the image for one screen is displayed on the plurality of displays as a whole, a line YC separation means for separating the input video signal into a luminance signal and a color signal for each scanning line. A line correlation detecting means for detecting the correlation of the scanning lines in the input video signal, a frame YC separating means for separating the input video signal into a luminance signal and a chrominance signal for each frame, and a frame between the input video signals. And a luminance from the line YC separation means and the frame YC separation means, which are controlled by the outputs of the motion detection means and the line correlation detection means. A mixer color demodulation unit that mixes and color demodulates the output of the signal and the color signal, and an interpolation process that is controlled by the output of the motion detection unit and that generates an interpolated luminance signal that interpolates the luminance signal from the mixer color demodulation unit. Means for inputting a luminance signal and a color signal from the mixer color demodulating means and an interpolating luminance signal from the interpolation processing means, and outputting a signal to be divided and displayed to each of the plurality of display devices. Display signal output means.

[Embodiment] In order to make the explanation easier to understand, the video signal of the original signal will be the NTSC color video signal of the current broadcasting system, and each display unit that integrally displays will be projected with the NTSC system video signal as an input. An embodiment of the present invention will be described with reference to the drawings.

In the figure, reference numeral 1 is an A / D conversion circuit for converting an input video signal from an analog signal into a digital signal having a configuration of 8 bits or the like,
2 is a timing generation circuit for timing the various circuits described below. 3 is a frame delayed to enable the same display on each display by the D / A color modulation circuit in the subsequent stage as an original signal. A 1-frame delay circuit for making the system in consideration of switching display, 4 is a line YC separation that separates a luminance signal and a chrominance signal, which is composed of an adder / subtractor between scanning lines, which is combined with 1H delay lines used especially in moving images. A circuit 5 is a line correlation detection circuit for detecting the correlation between scanning lines, and 6 is a 1-frame memory used for still images, a 262H delay line, an adder / subtractor, and the like between the inter-frame luminance and color signals. Frame YC separation circuit to separate,
7 is a frame memory such as a RAM for storing the previous one frame for adding and subtracting the previous frame and the current frame by the frame YC separation circuit 6, and 8 is a pattern displayed for improving the image quality. The output of the A / D conversion circuit 1 is a motion detection circuit that detects whether or not each circuit 3
To 8 respectively.

Next, 9 indicates the output signals of the line YC separation circuit 4 and the frame YC separation circuit 6 described above by the output signals of the line correlation detection circuit 5 and the motion detection circuit 8, for example, the brightness of the frame YC separation circuit 6 in the case of a still image. And the output of the color signal are mixed so as to extract the output of the luminance and the color signal of the line YC separation circuit 4 in the case of a moving image, and the color signals are RY (red difference signal) and BY (blue difference signal). ) Is a mixer color demodulation circuit for reproduction. Reference numeral 10 denotes an interpolation generation circuit for generating an interpolation luminance signal from an original luminance signal for inserting the signals of the output of the mixer color demodulation circuit 9 and each color difference signal by the detection signal of the motion detection circuit 8 between scanning lines, 11 is the interpolation generation circuit 10
A scan converter for converting the original luminance signal that has passed through 4 into 4 divisions for each of the displays 16 to 19, and 12 is an interpolation generation circuit 10
4 for each of the display units 16 to 19
A scan converter for performing scan conversion for division, and 13 for each color difference signal that has passed through the interpolation generation circuit 10 for each display 16 to 19
It is a scan converter that performs scan conversion for division. Furthermore,
14 performs color modulation by combining the original luminance signal scan-converted by each scan converter 11 to 13, the interpolation luminance signal, and the color difference signal, and performs D / A conversion to add a synchronization signal,
It is a video signal generation circuit that generates a signal to be displayed on each display 16 to 19, and is input to each of the displays 16 to 19 which are arranged so that they can be integrally displayed by the output of each of the video signal generation circuits 14. The display devices 16 to 19 equipped with are driven.

Next, the operation will be described. The input NTSC video signal is converted by the A / D conversion circuit 1 into, for example, an 8-bit digital signal. This digital signal is applied to the luminance signal Y in the line YC separation circuit and the frame YC separation circuit 6, respectively.
1, Y2 and color signals C1 and C2 are separated. The frame YC separation circuit 6 utilizes a frame memory 7 which stores one frame worth of digital signals to add and subtract signals of the current frame and the previous frame to separate them. The motion detection circuit 8 receives a digital signal as an input and subtracts and compares the previous frame signal output, which is the previous picture, and the frame signal output, which is the current picture, which have passed through the frame memory 7, and extracts the low-frequency component to extract the frame signals from each other. A signal difference, that is, whether or not there is a motion signal between frames, is detected and a detection signal is output. The line correlation detection circuit 5 receives a digital signal as an input and passes through a band pass filter of a color carrier, for example, and subtracts and compares the patterns before and after 2H (2 horizontal scanning periods) to detect whether there is a correlation between the lines. Output the detection signal.

Therefore, in the mixer color demodulation circuit 9, the input signal is the luminance signal Y1 from the line YC separation circuit 4 and the color signal C1 and the frame.
There are four types of luminance signal Y2 and color signal C2 from the YC separation circuit 6, and the control signals thereof are used as the detection signals of the line correlation detection circuit 5 and the motion detection circuit 8, respectively. Handle appropriately according to the data. This output includes dot jamming, dot crawling,
A luminance signal Y3 from which cross color interference, interlace interference and the like have been removed and a multiple color signal C3 (composite color difference signal of color difference signals RY and BY) are output.

Next, in the interpolation generation circuit 10, for example, the luminance signal Y3 of the mixer color demodulation circuit 9 is averaged by a 1H delay circuit and an adder and the like, and an interpolation signal Yi1 and a luminance signal Y3 of a 263H field are obtained through a coefficient unit of K. An interpolation signal Yi2 is generated through a coefficient unit of (1-K) through a memory, and the coefficient K of these two coefficient units is set to K = 0 for a still image and K for a moving image by an output detection signal of the motion detection circuit 8. = 1 is given and these two interpolation signals Yi1 and Yi2 are added to obtain an interpolation signal Yi. Further, the luminance signal Y3 is obtained through a 1H delay circuit and a predetermined delay circuit for correcting the signal processing time. Further, the multi-color signal C3 is passed through a predetermined delay circuit for correcting the signal processing time, and the multi-color signal Cr is obtained and output.

The above-mentioned luminance signal Yr, interpolation signal Yi, and multi-color signal Cr are 4
Use each scan converter 11,12,13 to split for screen display. This scan converter 11,12,
In 13, the signals handled are different but the operations are substantially the same, so the scan converter 11 will be described. This scan converter 11 connects two field memories in parallel, and generates a memory control signal from the horizontal and vertical synchronization signals so that when the input luminance signal Yr is written in one, the other is read out. The read signal is output by being divided into the respective displays 16, 17, 18, 19 by switching the switches of four circuits in time series. The switches of these four circuits are switched by the memory control signal. Therefore, with this scan converter 11, 12, 13, for example, the display 16
For the purpose of using the symbol a, the luminance signals Yr-a and the interpolation signals Yi-a from the scan converters 11 and 12 are combined so as to be taken out alternately every 1H, and are synthesized as luminance signals Y4-a. The multi-color signal Cr-a is read twice and output as the multi-color signal C4-a. Similarly, the luminance signals Y4-b to d and the multi-color signals C4-b to d are generated for the other displays, and a total of eight types of signals are output.

Therefore, the video signal generation circuit 14 converts the video signal into a video signal that can be displayed by each display. For example, the multi-color signal C4-a is 3.
The 58MHz color carrier is modulated to add a sync signal, and the luminance signal Y4-a is also added with a sync signal, and each is converted to an analog signal by the D / A converter, and is synthesized by an NTSC for the display unit 16 by the synthesizing circuit. Generate a signal. When this NTSC signal is transmitted to the display unit 16, the display is performed in the same manner as in the case of the interlace horizontal 525 scanning lines which receives and displays a normal NTSC signal. Other displays are also displayed in response to the NTSC signal.

Therefore, the images displayed on the displays 16 to 19 become one picture image if the display surfaces of the respective displays are arranged in one body and aligned, and one normal one display image is horizontal and vertical. Is doubled to achieve a large screen. Although the pattern is not non-interlaced, it becomes an extremely fine image at the level of one display, and a high-quality image in which the above various kinds of interference are removed can be obtained.

In the above-mentioned embodiment, an example in which the number of display devices is four is shown, but a multi-screen scan converter is provided and a display device corresponding thereto is provided to provide a multi-screen display. An integrated image can be obtained.

Further, if a normal display is provided with a luminance signal and a multi-color signal input terminal in the subsequent stage of the YC separation means, the D / A-converted luminance signal of the above-mentioned video signal generation circuit 14 is displayed on each display. By directly and independently combining the and the multi-color signal, a considerable part of the above-mentioned interfering signal generated in the YC separation means can be removed.

[Effects of the Invention] The following effects can be achieved by the above-described configurations and the respective actions.

(A) By the line correlation detection signal and the motion detection signal,
It is possible to reliably separate luminance / color signals not only in still images but also in moving images, and it is possible to eliminate the occurrence of interference such as dot crawl and cross color that are particularly noticeable on a large screen.

(B) Although the display is integrated as a multi-screen to make a large screen, the interpolation signal is accurately generated by the motion detection and line correlation detection signals, and the horizontal scanning line of the display is inserted without damaging it. There is no flicker (especially interline flicker), and a fine, high-quality, large screen can be obtained.

[Brief description of drawings]

The drawings are block diagrams showing a multi-screen display system according to an embodiment of the present invention. 1 ... A / D conversion circuit, 4 ... Line YC separation circuit, 6 ... Frame YC separation circuit, 9 ... Mixer color demodulation circuit, 10 ... Interpolation generation circuit, 11-13 ... Scan converter, 14 ... … Video signal generation circuit, 16 to 19 …… Display,

Claims (1)

(57) [Claims] 1. An image for one screen of an input video signal is divided and displayed on each of a plurality of display devices arranged vertically and horizontally, and the image for one screen is displayed on the entire plurality of display devices. In such a multi-screen display system, a line YC separation means for separating the input video signal into a luminance signal and a color signal for each scanning line, and a line correlation detection means for detecting the correlation of the scanning lines in the input video signal, A frame YC separation unit that separates an input video signal into a luminance signal and a chrominance signal for each frame; a motion detection unit that detects movement between frames in the input video signal; a motion detection unit and the line correlation detection Controlled by the output of the means, the output of the luminance signal and the color signal from the line YC separation means and the frame YC separation means, a mixer color demodulation means for mixing and color demodulating, Interpolation processing means for generating an interpolated luminance signal by interpolating a luminance signal from the mixer color demodulating means, which is controlled by an output of the motion detecting means; and a luminance signal, a color signal and the interpolation processing from the mixer color demodulating means. And a split display signal output unit for outputting the signals to be split-displayed to the plurality of displays, respectively.