JP2000224577A - Device for synthesizing and displaying picked-up image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display the synthetic image of four picked-up images from four cameras on the screen of a monitor display device with high resolution without a flicker in the minute part of the screen. SOLUTION: A synthesizing and displaying device is provided with the four same-type video cameras CM-1 to CM-4, the monitor display device TM having scanning lines being nearly twice as many as those of the four cameras, an image synthesizing circuit IC which synthesizes the picked-up image signals from the four video cameras so that the synthetic image has nearly the double number of pixels in horizontal and vertical directions compared with that of picked-up image signals from the video cameras and so that the each of the images of the picked-up image signals from the cameras to occupy the quadripartite areas of the screen and a scanning converting circuit SC which supplies the synthetic image signal from the circuit to the monitor display device and converting it by scanning to be displayed on the device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a synthesized image display device.

[0002]

2. Description of the Related Art For example, when there are four places to be monitored and the four places are to be monitored using a video camera and a monitor display device, four video cameras and four However, this is uneconomical and has the disadvantage that the volume occupied by the monitor display device at the monitoring station is increased.

Therefore, conventionally, images taken from four video cameras are combined and displayed on one monitor display device.

[0004]

However, when images taken from four video cameras are combined and displayed on one monitor display device, it is economical and the monitor display device at the monitoring station is not economical. Although the occupied volume for installation is small, it is preferable. On the other hand, the pixels constituting the images captured by the four video cameras are thinned out by １ ／ in the horizontal and vertical directions, or １ ／. Therefore, the synthesized picked-up image displayed on the screen of the monitor display device has a disadvantage that the resolution is deteriorated and a fine portion of the screen flickers.

In view of the above, the present invention provides a method of displaying a composite image of four captured images from four video cameras on a screen of a monitor display device at a high resolution without flickering of a fine portion of the screen. It is an object of the present invention to propose a synthesized image display device capable of capturing captured images.

[0006]

According to a first aspect of the present invention, there is provided a composited image display apparatus according to the present invention, in which four video cameras of the same system and scanning lines approximately twice the number of scanning lines of the four video cameras are provided. Monitor display device having the same number of pixels and the number of pixels in the horizontal and vertical directions each being approximately twice the number of pixels in the horizontal and vertical directions of the image signals captured by the respective video cameras. And an image synthesizing circuit for synthesizing each image of the captured image signals from the four video cameras so as to occupy four divided areas of the screen, and a synthesized image signal from the image synthesizing circuit to a monitor display device. And a scan conversion circuit for performing scan conversion so as to be supplied and displayed on the monitor display device.

According to the first aspect of the present invention, the image synthesizing circuit converts the captured image signals from the four video cameras of the same system into the horizontal and vertical pixel numbers of the captured image signals from the respective video cameras. Have approximately twice the number of pixels in the horizontal and vertical directions, respectively, and combine the images of the captured image signals from the four video cameras so as to occupy the four divided areas of the screen. The synthesized image signal from the image synthesizing circuit is supplied to a monitor display device having approximately twice the number of scan lines of the four video cameras, and scan conversion is performed so that the monitor display device can display the same. Do.

According to the first aspect of the present invention, the image synthesizing circuit synthesizes the picked-up image signals from the four video cameras, and the scan conversion circuit reduces the number of scanning lines of the synthesized image signal from the image synthesizing circuit. The scan conversion is performed twice, and the composite image signal whose number of scanning lines is converted by the scan conversion circuit is supplied to the monitor display device.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first aspect of the present invention is to provide four video cameras of the same system, a monitor display device having approximately twice the number of scanning lines of the four video cameras; The number of pixels in the horizontal and vertical directions is approximately twice as large as the number of pixels in the horizontal and vertical directions of the image signals from the video cameras. An image synthesizing circuit for synthesizing each image of the captured image signal so as to occupy four divided areas of the screen, and a synthesized image signal from the image synthesizing circuit is supplied to a monitor display device, and the monitor display device And a scan conversion circuit that performs scan conversion so as to be displayed.

According to a second aspect of the present invention, in the composited image display apparatus according to the first aspect of the present invention, the number of horizontal and vertical pixels of a captured image signal from any one of the four video cameras is determined. An up-converter for up-conversion is provided for each of them, and the up-converted picked-up image signal from the up-converter and the synthesized image signal from the image synthesizing circuit are selectively supplied to the scan conversion circuit. This is a composite display device for a captured image.

A specific example of the embodiment of the present invention will be described in detail below with reference to the drawings. CM1 to CM4 are
For example, four video cameras of the NTSC system (for example,
CCD color camera). TM is, for example, SXG
A (Super Extended Graphics Array) type monitor display device (monitor display device using a cathode ray tube, a liquid crystal display device, etc.) used as a television monitor. This SXGA type monitor display device was developed as a monitor display device for a computer. The number of pixels of a display image (display image) is 1280 in the horizontal direction and 1024 in the vertical direction.
It has the ability to simultaneously display four images (captured images) from an NTSC television camera. The TV monitor TM has approximately twice as many scanning lines as the four video cameras CM1 to CM4.

[0012] The captured color image signals (captured color video signals) from the video cameras CM1 to CM4 are supplied to an NTSC decoder NDC, and each of them is separately decoded.
The image is supplied to the image synthesizing circuit IC to perform image synthesis. The image synthesizing circuit IC converts the captured image signals from the four video cameras CM1 to CM4 into horizontal and vertical pixels substantially twice the number of horizontal and vertical pixels of the captured image signals from the respective video cameras. In addition, the images are combined so that the images of the captured image signals from the four video cameras CM1 to CM4 occupy the four divided areas of the screen.

A changeover switch SW2 and a scan conversion circuit SC convert the synthesized picked-up color image signal from the image synthesis circuit IC.
To the television monitor TM so that four captured images DP1 to DP4 of the four video cameras CM1 to CM4 are simultaneously displayed on the screen P. The scan conversion circuit SC supplies the synthesized image signal from the image synthesis circuit SC to the monitor display device (television monitor) TM,
Scan conversion is performed so that the image can be displayed on the television monitor TM.

The picked-up color image signals from the four video cameras CM1 to CM4 are supplied to a changeover switch SW1.
The changeover switch SW1 selects any one of the captured color image signals from the four video cameras CM1 to CM4, and supplies the selected captured color image signal to the up-converter UC. Then, the number of pixels in the horizontal and vertical directions of the captured color image signal is up-converted to double each. The upconverted captured color image signal from the upconverter UC is supplied to the television monitor TM through the changeover switch SW2 and the scan conversion circuit SC, and the captured image from the video camera selected from the video cameras CM1 to CM4. Is displayed on the entire screen P.

Next, the above-described changeover switches SW1,
The SW2 will be described. Video cameras CM1 to CM4
When the composite image of the four captured images from is displayed on the screen P of the television monitor TM, the changeover switch SW2 is switched to the image compositing circuit IC side. Video camera CM1
When the captured image from a certain video camera changes while monitoring the four captured images from the CM 4 and it is desired to particularly monitor only the captured image, the video camera for the captured image to be monitored is switched. By selecting the switch SW1 and switching the changeover switch SW2 to the up-converter UC side, the captured image to be particularly monitored is displayed on the screen P of the television monitor TM.
It will be displayed full and monitored.

Next, referring to FIG. 2, NT in FIG.
The SC decode NDC and the image synthesizing circuit IC, in particular, the image synthesizing circuit IC will be further described. The captured color image signals from the video cameras CM1 to CM4 of the NTSC system shown in FIG.
The luminance signals Y and the color difference signals Cr are supplied to the C decoders NDC1 to NDC4 and decoded, respectively.
Cb are obtained, and individual A / D converters CY1 to CY
It is supplied to Y4 and CC1 to CC4 and digitized. In this case, A / D converters CY1 to CY for luminance signals
At 4, the analog luminance signal Y is converted into an 8-bit digital luminance signal. A / D for color difference signal
In the converters CC1 to CC4, the analog color difference signals CrCb
Are converted into 8-bit digital color difference signals CrCb. These A / D converters CY1, CC1 to CY4,
The digital luminance and color difference signals obtained from CC4 are 4:
It is called a 2: 2 component color image signal (component color video signal).

Next, the image composition in the image composition circuit in FIG. 2 will be described with reference to FIG. The NTSC cameras 1-4 and the SXGA monitor in FIG. 3 correspond to the video cameras CM1-CM4 and SXGA in FIG. 1, respectively.
This is equivalent to a television monitor TM of a system. And FIG.
When combining “A”, “B”, “C”, and “D” as captured images from the video cameras CM1, CM2, CM3, and CM4 and projecting the combined image on the screen of an SXGA monitor Is shown.

The number of scanning lines on the imaging surfaces of the NTSC cameras 1 to 4 is 525, and the effective number of scanning lines is about 480. Therefore, as shown in FIG.
In the effective scanning line of each first field of the SC cameras 1 to 4,
When numbers from 1 to 241 are assigned, the effective scanning line of each second field is assigned from 264 (= 263 + 1) to 504
Can be numbered up to.

A1 to A4 and B1 to B4 in FIG.
Are frame memories that can perform writing and reading independently of each other. A / D converters CY corresponding to the captured color image signals from the video cameras CM1 to CM4, respectively.
1 to CY4 and one frame of digital luminance and color difference signals (YCrCb) indicating images “A”, “B”, “C”, and “D” from CC1 to CC4, respectively. ~ A4 and B1 ~ B4
And the frame memories B1 to B
4 and alternately from A1 to A4, the images "A",
One frame of digital luminance and color difference signals (YCrCb) indicating “B”, “C”, and “D” are read out for each frame, and the images “A”,
A digital combined luminance and color difference signal T (YCrCb) indicating a combined image of “B”, “C” and “D” is output.

Referring now to FIG. 4, FIG.
The effective pixels of the imaging units of the video cameras CM1 to CM4 of the C system are shown as 753 pixels in the horizontal direction and 482 pixels in the vertical direction, and have 362,946 (= 753 × 482) pixels as a whole. The frequency of the clock signal supplied to the A / D converters CY1 to CY4 and CC1 to CC4 in FIG.
Assuming that the frequency is 4.3 MHz, the number of effective pixels in the horizontal direction of the captured image of the NTSC system is 753 as shown in FIG. 4A. Thus, the number of horizontal effective pixels of one scanning line of the monitor is 753 × 2 = 1506. However, SX
The number of horizontal effective pixels of the GA monitor is 1 as shown in FIG. 4C.
Since it is 280, a combined image of the captured images from the four NTSC cameras 1 to 4 cannot be displayed on the SXGA monitor. By the way, the current monitor of the NTSC system performs so-called overscan display, and does not display all the effective pixels in the horizontal direction. % To 20%, the number of pixels actually displayed in the horizontal direction is about 678 to 602. on the other hand,
The SXGA monitor takes 1280 表示 1505 = 0.85 considering that display is performed without overscan.
Therefore, as shown in FIG. 4B, digitally synthesized captured color image signals are stored in the memories A1 to A4 and B1 to B4,
If 15% of the number of pixels in the horizontal direction is deleted and read, and they are combined, the combined captured image can be displayed on the SXGA monitor screen as shown in FIG. 4C.

Although the number of effective scanning lines in the vertical direction of the SXGA monitor is 1024, twice the number of scanning lines (482) of the color image signal picked up from the NTSC camera is 964, and the number of effective scanning lines in the vertical direction of the SXGA monitor is 964. Since the number of pixels, that is, 1024 of the number of effective scanning lines, has room, it is not necessary to delete the horizontal scanning lines of the captured image signal from the NTSC camera. In this case, as shown in FIG. 4C, a pixel of 60 pixels in the vertical direction and 1280 pixels in the horizontal direction in the effective screen of the SXGA monitor is divided into three in the vertical direction, and each pixel is divided into 20 × 1280 pixels.
What is necessary is just to make the area of the pixels a non-display area.

Next, the scan conversion circuit SC in FIG. 1 will be further described with reference to FIG. Now, when the frequency of the clock supplied to the A / D converter in FIG. 2 is 14.3 MHz as described above, the NTSC digital color image signal and the SXGA digital color image signal are compared. In a color image signal, the number of horizontal scanning lines is 525 and the horizontal scanning frequency is 15.7.
5 kHz, the frame frequency is 30 Hz, and the pixel clock frequency is 14.31 MHz, whereas the color image signal of the SXGA system has 1068 horizontal scanning lines, 63.99 kHz horizontal scanning frequency, and 60 frame frequency.
Hz and the pixel clock frequency are 114.5 MHz, which are different from each other, so that the scan conversion circuit SC is required.

Considering the difference in standards between the NTSC digital color image signal and the SXGA digital color image signal, consider displaying a digital color image signal at the same frame frequency. The horizontal frequency of the SXGA digital color image signal is 2.034 (= 1) of the horizontal frequency of the NTSC digital color image signal.
068 ÷ 525) times. By the way, the digital color image signal of the NTSC system is an interlaced scanning system, while the digital color image signal of the SXGA system is a non-interlaced scanning system.
Since the ratio of the digital color image signal of the C system to the frame frequency is 4.068 (= 2.034 × 2), the horizontal scanning frequency of the digital color image signal of the SXGA system is 15.75 kHz × 4.68. = 63.99k
Hz.

The number of horizontal clocks of the NTSC digital color image signal is 910, whereas the number of horizontal clocks of the SXGA digital color image signal is 179.
0. Assuming the same horizontal frequency,
The clock frequency of the digital color image signal of the SXGA system is 1.967 (= 1790 ÷ 910) times the clock frequency of the digital color image signal of the NTSC system. Is 4.068 times the horizontal frequency of the digital color image signal of the NTSC system.
The clock frequency of the digital color image signal of the GA system is 8.0 (= 1.967 × 4.068) times the clock frequency of the digital color image signal of the NTSC system. Is 114.5 MHz (= 14.31 M
Hz × 8).

The speed conversion of the NTSC digital color image signal and the SXGA digital color image signal is performed by the scan conversion circuit shown in FIG. The 16-bit synthetic imaging digital luminance and color difference signals output from the image synthesizing circuit of FIG. 2 are supplied from an input terminal T4 to a matrix circuit MX to be matrixed, and the 8-bit synthetic imaging digital red, green, and blue signals are respectively output. obtain.

The combined red, green and blue signals of 8 bits each from the matrix circuit MX are converted into 14.3 signals.
Buffer memory BMR using a clock signal of MHz.
A, BMGA, BMBA and BMRB, BMGB, BM
BB is written alternately for each frame, and 114.
Using a clock signal of 5 MHz (= 14.3 MHz × 8), a buffer memory (2-frame memory) BMRB,
BMGB, BMBB and BMRA, BMGA, BMBA
Are read alternately for each frame.

Buffer memories BMRB, BMGB, BM
The composite imaging digital red, green, and blue signals alternately read out from the BB and BMRA, BMGA, and BMBA for each frame are supplied to the D / A converters CR, CG, and CB, and are converted into analog signals. Analog red, green and blue signals are passed through amplifiers AR, AG and AB to output terminal T.
The signals are output to R, TG, and TB, and the respective outputs are supplied to an SXGA monitor (SXGA television monitor TM) to be displayed on the screen.

The SXGA synchronizing signal from the input terminal TI is output to the output terminal TO via the amplifier AS, and is supplied to the SXGA television monitor TM.

Next, the upconverter UC in FIG. 1 will be further described with reference to FIG. Input terminal T2
Supplies an NTSC-captured color image signal (NTSC signal) from an arbitrary one of the video cameras CM1 to CM4 to an A / D converter and a Y / C separation circuit CS to perform A / D conversion. After conversion and Y / C separation, digital luminance and color difference signals (YCrC
Obtain b). Note that an 8-bit digital color difference signal (CrC
b) is a time-division signal of the digital color difference signals (Cr) and (Cb).

The NTSC digital luminance and color difference signals (YCrC) from the A / D converter and the Y / C separation circuit CS.
b) is simultaneously written into both the line memories LM1 and LM2 that can store two line signals, and is stored in the line memories LM3 and LM4 that can store two line signals. By reading out the line signals for two lines of the SXGA system obtained by interpolating the line signal before one line by one pixel signal in the horizontal direction and the vertical direction respectively, the output terminal T3
The interpolated NTSC digital luminance and color difference signals (YCrCb) are output and supplied to the SXGA television monitor TM through the scan conversion circuit SC.

Referring to FIG. 7, FIG. 7A shows 753 pixels in the horizontal direction and 482 pixels in the vertical direction, which are effective pixels of the image pickup unit of the NTSC video cameras CM1 to CM4. = 753 × 482) pixels, about 15% in the horizontal direction is deleted, and 6% in the horizontal direction.
40, 482 vertically, ie 308,480
(= 640 × 482) pixels are shown. FIG. 7B shows the SX
This figure shows an effective screen composed of 1280 pixels in the horizontal direction and 1024 pixels in the vertical direction of a GA television monitor. FIG.
A, 640 pixels in the horizontal direction and 482 pixels in the vertical direction, that is, 280,480 (= 640 × 482) pixels are interpolated in the horizontal and vertical directions, respectively, to obtain 1280 pixels in the horizontal direction. A captured image composed of 964 pixels in the vertical direction, that is, 1,233,920 (= 1280 × 964) pixels is displayed on the SXGA monitor TM in FIG. 7B.

FIG. 7C illustrates pixel interpolation.
The squares indicated by thick lines indicate the original pixels, and the squares indicated by thin lines indicate the interpolated pixels. Then, for example, the level of the pixel signal interpolated in the horizontal direction becomes, for example, the average value of the levels of the pixel signals on both sides thereof, and the interpolated line signal is the line signal of the line immediately above (the original pixel signal). And interpolated pixel signals).

Next, referring to FIG. 8, the video cameras CM1 to CM4 shown in FIG.
ay) When a camera is used to display a composite image of the captured images “A”, “B”, “C” and “D” from the VGA cameras 1, 2, 3 and 4 on the screen of the SXGA monitor Will be described. The standard of the captured color image signal from the VGA camera is as follows.

Number of scanning lines 525 Number of effective scanning lines 480 Horizontal scanning frequency 31.46 kHz Vertical scanning frequency 60 Hz Frame frequency 60 Hz Clock frequency 25.175 MHz Number of horizontal clocks 800 Number of horizontal effective clocks 640

Even if the number of effective pixels in the horizontal and vertical directions of the color image signal picked up by the VGA camera is quadrupled,
Since the number of pixels in the horizontal and vertical directions of the display screen of the SXGA monitor does not exceed both, the number of pixels in the horizontal and vertical directions of the color image signal captured by the VGA camera is not reduced, and the number of pixels in the four VGA cameras is reduced. Can be displayed on the SXGA monitor.

Next, referring to FIG. 9, a PAL camera is used as each of the video cameras CM1 to CM4 in FIG.
Captured images “A” from L cameras 1, 2, 3 and 4;
The case where the combined image of “B”, “C”, and “D” is displayed on the screen of the SXGA monitor will be described. The standard of the captured color image signal from the VGA camera is as follows.

Number of scanning lines 625 Number of effective scanning lines 574 Horizontal scanning frequency 15.625 Hz Vertical scanning frequency 50 Hz Frame frequency 25 Hz Clock frequency 14.188 MHz Number of horizontal clocks 908 Number of horizontal effective clocks 739

Although the effective clock number of the color image signal picked up from the PAL camera is smaller than the effective clock number of the color image signal picked up from the NTSC camera as described above, the effective clock number of the color image signal picked up from the PAL camera is small. Is about 20% larger than the number of effective pixels in the vertical direction of the color image signal captured from the NTSC camera. Therefore, four times the number of scanning lines of the captured color image signal from the PAL camera exceeds the number of effective scanning lines of the SXGA monitor. Therefore, the effective scanning line number 574 of the color image signal picked up from the PAL camera is deleted by about 13% and 5
If it is set to 00, four times the number of scanning lines of the color image signal picked up from the PAL camera will not exceed the number of effective scanning lines of the SXGA monitor, and obtained by synthesizing the images picked up from the four PAL cameras. The composite image can be displayed on an SXGA monitor.

In the above specific example, the case where the SXGA type monitor display device is used as the monitor display device has been described.
0, UXGA (Ultra Extend
An ed Graphics Array) type monitor display device can also be used.

[0040]

According to the first aspect of the present invention, there are provided four video cameras of the same system, a monitor display device having the number of scanning lines approximately twice as large as the number of scanning lines of the four video cameras, and The number of pixels in the horizontal and vertical directions is approximately twice as large as the number of pixels in the horizontal and vertical directions of the image signals from the video cameras. An image synthesizing circuit for synthesizing each image of the captured image signal so as to occupy four divided areas of the screen, and a synthesized image signal from the image synthesizing circuit is supplied to a monitor display device, and the monitor display device Since it has a scan conversion circuit that performs scan conversion so that it can be displayed,
It is possible to obtain a captured image composite display device that can display a composite image of four captured images from four video cameras on the screen of the monitor display device at high resolution without flickering of the screen fine portion. .

According to the second aspect of the present invention, in the captured image synthesizing display apparatus of the first aspect of the present invention, the horizontal and vertical pixels of the captured image signal from any one of the four video cameras are provided. An up-converter for up-converting each of the numbers to double the number, and selectively supplying the up-converted captured image signal from the up-converter and the synthesized image signal from the image synthesis circuit to the scan conversion circuit. As a result, the same effect as that of the first invention can be obtained, and an arbitrary captured image among the captured images from the four video cameras can be displayed on the monitor display device by approximately 2 in the horizontal and vertical directions. It is possible to obtain a composited image display device that can display a captured image that can be displayed twice as large.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a combined image display apparatus for captured images according to a specific example of an embodiment of the present invention.

FIG. 2 is a block diagram illustrating an example of an NTSC decoder and an image synthesis circuit of a captured image synthesis display device according to a specific example.

FIG. 3 is an explanatory diagram showing a relationship (1) between a camera image and a monitor image in a composite display of a captured image.

FIG. 4 is an explanatory diagram of a composite display of a captured image of a camera.

FIG. 5 is a block diagram showing an example of a scan conversion circuit of a combined image display device of a specific example.

FIG. 6 is a block diagram showing an example of an up-converter of a combined image display device of a specific example;

FIG. 7 is an explanatory diagram of up-conversion.

FIG. 8 is an explanatory diagram illustrating a relationship (2) between a camera image and a monitor image in a composite display of a captured image.

FIG. 9 is an explanatory diagram illustrating a relationship (3) between a camera image and a monitor image in a composite display of a captured image.

[Explanation of symbols]

CM1 to CM4 Video camera, NDC, NDC1 to 4
NTSC decoder, IC image synthesis circuit, SW1, S
W2 changeover switch, UC up converter, S
C Scan conversion circuit, TM TV monitor.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C054 EB03 EC01 EC03 EH04 EJ07 FB03 FE18 HA18 5C063 AA02 AA06 AA20 AB01 AB03 BA03 CA01 CA05 CA29 CA38 CA40 5C082 AA27 BA41 BC19 CA55 CA62 CA84 CB01 MM10

Claims (2)

[Claims] 1. Four video cameras of the same system, a monitor display device having a number of scanning lines approximately twice as large as the number of scanning lines of the four video cameras, and a captured image from the four video cameras The signal has a number of pixels in the horizontal and vertical directions approximately twice as large as the number of pixels in the horizontal and vertical directions of the image signal captured by each of the video cameras, and each of the image signals captured by the four video cameras. An image synthesizing circuit for synthesizing an image so as to occupy four divided areas of a screen, and a synthesized image signal from the image synthesizing circuit is supplied to the monitor display device and scanned so as to be displayed on the monitor display device. And a scan conversion circuit for performing a conversion. 2. The combined image display apparatus according to claim 1, wherein the number of pixels in the water and vertical directions of a captured image signal from any one of the four video cameras is doubled. An up-converter for up-conversion is provided, and the up-converted captured image signal from the up-converter and the synthesized image signal from the image synthesizing circuit are selectively supplied to the scan conversion circuit. A composite display device of a picked-up image.