JP3683644B2 - Video signal converter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a video signal conversion apparatus that converts a non-composite video signal output from a computer and outputs the converted video signal.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as this type of video signal conversion device, a device that converts a video signal output from a computer in the RGB format into a composite signal so that it can be received by an ordinary television receiver is known. Television receivers are widespread from small to large, so if you want to show a large number of computer screens displayed on a computer monitor screen (for presentations, education, etc.) In addition, such a video signal converter is useful. Also, once converted to a composite signal, it can be handled as a normal video signal, so it can be easily recorded on a VTR or printed by a video printer.
[0003]
[Problems to be solved by the invention]
However, the conventional video signal converter only converts the non-composite signal output from the computer into a composite signal. However, even though a large-sized television is popular, it is up to several tens of inches. There is a problem that it is still difficult to display a large image exceeding the above. Also, operations such as replacing a part of the video with another video are difficult because a dedicated mixer is required.
[0004]
The present invention has been made to solve the above-described problems, and converts a video signal output as a non-composite signal from a computer into a composite signal, and easily configures a large screen or part of a video easily. It was made for the purpose of realizing a modified video signal converter.
[0005]
[Means for solving the problems and their functions and effects]
In order to achieve this object, the video signal converter of the present invention employs the following means. That is, the video signal converter of the present invention is
Input means for inputting a non-composite video signal output from a computer;
Storage means for temporarily storing the input video signal;
Conversion output means for reading out the stored video signal, taking out each of the screens constituting the video as an image signal divided into n × n (n is an integer of 2 or more) , and converting it into a composite signal ;
Switching means for inputting a composite signal from the conversion output means and switching between the composite signal and other composite signals;
And the output from the switching means is connected to the television receiver, respectively .
[0006]
This video signal conversion apparatus inputs a video signal output from a computer in a non-composite format by an input means, and temporarily stores it in a storage means. The storage means may have a capacity for storing video for one screen, but may be configured even with a capacity of a line buffer corresponding to one scanning line. The stored video signal is read out, and the conversion output means extracts each of the screens constituting the video as image signals obtained by dividing the screen into n × n, and converts them into composite signals for output. That is, the output of the composite signal from the video signal conversion device is performed for each screen obtained by dividing the image into n × n. Therefore, if this composite signal is input to n × n television receivers, a multi-vision of the television receiver n × n is immediately configured. Moreover, since there is provided a switching means of the video signal, it is possible that can interchanged one or a plurality of images of this. It is also possible to display other video signals by outputting them to some television receivers.
[0007]
Other aspects of the invention
As another aspect of the present invention, for example, setting means capable of setting the number n × n of image divisions performed by the conversion output means is provided, and the number of screen divisions such as 2 × 2 and 3 × 3 according to the setting. Various configurations can be considered, such as a configuration that makes it possible to change. The non-composite format video signal includes a CYM format signal in addition to an RGB signal.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the video signal conversion apparatus according to the present invention will be described with reference to examples. FIG. 1 is an explanatory diagram showing a connection relationship between a video signal conversion apparatus 10 as one embodiment of the present invention, a computer 20 and a television receiver TVmn, and FIG. 2 is a schematic configuration diagram of the video signal conversion apparatus 10. As shown in FIG. 1, the same video image displayed on the monitor 22 from the computer 20 is output to the video output connector CN1 in the RGB format, and the video signal converter 10 transmits this signal to the cable 24. In the embodiment, it is output as a composite signal to 3 × 3 = 9 television receivers TV11 to TV33. For this purpose, the video signal converter 10 is provided with output pin connectors 11 to 19 in addition to the input connector CN2 to which the cable 24 is connected.
[0009]
A video cable is connected to the pin connectors 11 to 19, and composite video signals are output to the television receivers TV11 to TV33. Accordingly, a single video signal converter 10 can display video on up to nine television receivers.
[0010]
As shown in FIG. 2, the video signal converter 10 includes an RGB signal input circuit 50 that inputs an analog RGB format video signal and outputs it as a digital signal for each pixel. The RGB signal input circuit 50 is a PLL circuit that samples an input analog RGB signal at a predetermined sampling time based on the horizontal synchronization signal HS and the vertical synchronization signal VS and develops the sampled signal in the frame memory 52.
[0011]
In addition, the video signal converter 10 includes a CPU 54 for setting sampling times in the RGB signal input circuit and exchanging data with the frame memory 52 as necessary, a ROM 55 storing a program, a work, and the like. A RAM 56, which is a memory, is also provided, but the RGB signal sampling and transfer to the frame memory 52 are performed by the RGB signal input circuit 50. The sampling clock CLK1 is determined by the number of data included in one horizontal synchronizing signal period of the RGB format video signal. The RGB signal input circuit 50 locks the sampling clock CLK1 to a frequency corresponding to the number of data for one scan of the frame memory 52, cuts out data for the same number of pixels for each scan line, 52. The frame memory 52 is a dual port memory, and includes a writing circuit 58 that sequentially writes the parallel data output from the RGB signal input circuit 50 sequentially from a predetermined address. The video signal converter 10 includes a bus 59 for connecting these circuits, nine readout conversion circuits 61 to 69 for reading out data for each divided area of the frame memory 52 and converting the data into composite signals, and readout. A CRTC 70 for controlling the conversion circuits 61 to 69 is provided. The sampling clock CLK1 of the RGB signal input circuit 50 and the operation clock CLK3 of the read conversion circuits 61 to 69 and the CRTC 70 are completely asynchronous.
[0012]
In the frame memory 52 which is a dual port memory, data can be read out by the read conversion circuits 61 to 69 independently of data writing from the RGB signal input circuit 50 via the writing circuit 58. . At this time, the video signal is sampled by the clock CLK1 of the RGB signal input circuit 50, and the sampled data is sequentially written from a predetermined address of the frame memory 52. The read conversion circuits 61 to 69 read the image data written in this way serially and convert it into a composite signal. The operations of the read conversion circuits 61 to 69 are set by the CRTC 70, and read data in accordance with the format required by the television receiver TVmn.
[0013]
The read conversion circuits 61 to 69 for reading such image data will be further described. Read conversion circuits 61 to 69 can be programmed in advance under the control of CRTC 70. When a predetermined address is written from the CRTC 70 to the registers in the read conversion circuits 61 to 69, the read conversion circuits 61 to 69 repeatedly read data in the written address range. The read conversion circuit 61 is an image P11 at the upper left corner of the screen divided into 3 × 3, the read conversion circuit 62 is the image P12 at the center, the read conversion circuit 63 is the image P13 at the upper right corner,. The read conversion circuit 69 reads the image P33 at the lower right corner, respectively. In addition, each of the read conversion circuits 61 to 69 can read out in an interlaced manner.
[0014]
FIG. 3 schematically shows this state. It is assumed that a video signal of horizontal 1120 × vertical 760 dots is output from the computer 20 and is written in the frame memory 52 as it is. In this case, as shown in FIG. 3, for example, the read conversion circuit 61 reads the image P11 in the upper left corner of the screen, but the read clock CLK3 is synchronized with the frequency of the video signal of the television receiver TV11. The video for 373 (1120/3) dots in the horizontal direction × 252 (760/3) lines in the vertical direction is reproduced. The read conversion circuits 61 to 69 convert the video signal read in this way into a composite signal and output it from the pin connectors 11 to 19. Since the composite signals output from the pin connectors 11 to 19 have a size corresponding to one screen of the TV screen, the images of the screens P11 to P33 are displayed on the TV receivers TV11 to TV33, respectively. If the television receivers TV11 to TV33 are configured in 3 × 3 as shown in FIG. 1, the original video is composed and displayed by the nine television receivers TV11 to TV33. .
[0015]
Note that the address range of the data read from the frame memory 52 by the read conversion circuits 61 to 69 can be changed according to the value in the internal register of the read conversion circuits 61 to 69, so that the bus 59 is connected to the read conversion circuits 61 to 69. If the value of the internal register can be updated from the CPU 54, the frame memory 52 can be divided into 2 × 2 and output. When the resolution of the video signal from the computer 20 is low, the read address range set in each of the read conversion circuits 61 to 69 by the CRTC 70 becomes narrow, and as a result, the video reproduced on each television receiver TV. Becomes rough.
[0016]
According to the present embodiment described above, the video displayed on the monitor 22 of the computer 20 can be displayed on the large screen very easily. Even with a television receiver of about 39 inches that is easily available for consumer use, a display device with a size of nearly 120 inches can be easily configured. For this reason, the screen of the computer 20 can be displayed to a large number of people, and presentations and large-scale exhibitions can be easily performed.
[0017]
Although one embodiment of the present invention has been described above, the present invention is not limited to such an embodiment, and can of course be implemented in various modes without departing from the gist of the present invention. . For example, as shown in FIG. 4, a connection switch 110 may be placed between the video signal converter 10 and the television receivers TV11 to TV33, so that the configuration of the monitor 22 screen of the computer 20 can be freely changed. Further, the connection switcher 110 can switch a part of the 3 × 3 image to an external video input (for example, a video signal from a video tape recorder). In the example shown in FIG. 4, the video image reproduced from the video tape recorder 100 is always displayed as the image on the TV 11, and the image P33 at the lower right corner of the screen is originally displayed on the TV receiver TV23 at the center right side. Some images are displayed off the position on 22 such that the image P32 is displayed on the television receiver TV33 in the lower right corner.
[0018]
According to such a configuration, when the monitor screen of the computer 20 is displayed on a plurality of television receivers, the display position of the video can be freely configured with the screen of the television receiver as a unit. It is also easy to capture an external video as a part thereof. Therefore, the degree of freedom of multi-screen display can be increased.
[0019]
It is also preferable to use the connection switcher 110 that can be controlled by the computer 20 and switch the connection freely in accordance with the video to be displayed to enhance the video display effect. In FIG. 4, the connection switching is shown as one-to-one, but if one-to-many connection is allowed, the same video is displayed on all television receivers according to the video to be displayed, It can also be used to display the same image on a television receiver. In this embodiment, the connection switcher 110 is described as having a separate structure from the video signal converter 10, but a configuration in which the connection switcher 110 is built in the video signal converter 10 is also suitable. In this case, it becomes easy to control connection switching from the CPU 54.
[0020]
Further, in the above embodiment, the frame memory 52 is a dual port memory, and the image reading is performed by the read conversion circuits 61 to 69. However, if the read range is fixed, it can be easily achieved by a discrete circuit configuration. It can also be realized.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.
FIG. 2 is a block diagram showing an internal configuration of the video signal conversion apparatus 10;
FIG. 3 is a schematic diagram showing a state of video conversion.
FIG. 4 is an explanatory diagram showing another embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Video signal converter 11 thru | or 19 ... Pin connector 20 ... Computer 22 ... Monitor 24 ... Cable 50 ... RGB signal input circuit 52 ... Frame memory 54 ... CPU
55 ... ROM
56 ... RAM
58 ... Write circuit 59 ... Bus 61 to 69 ... Read conversion circuit 70 ... CRTC
71 ... Oscillator CN1 ... Video output connector CN2 ... Input connector TVmn ... Television receiver

Claims (2)

Input means for inputting a non-composite video signal output from a computer;
Storage means for temporarily storing the input video signal;
Conversion output means for reading out the stored video signal, taking out each of the screens constituting the video as an image signal divided into n × n (n is an integer of 2 or more) , and converting it into a composite signal ;
Switching means for inputting a composite signal from the conversion output means and switching between the composite signal and other composite signals;
And a video signal converter in which outputs from the switching means are respectively connected to a television receiver . The video signal converter according to claim 1,
The switching means can input an external video signal as one of the composite signals, displays an image based on the video signal on one of the television receivers, and displays on another television receiver. , Displaying a plurality of composite signals output from the conversion output means and replaced by the switching means
Video signal converter.

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