JPS6151316B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a full-dot type graphic display device. More specifically, when displaying an image consisting of more pixels than the total number of pixels on the display screen, it is possible to display the original image reduced to match the number of pixels on the display, or to display the original image at the same magnification. The present invention relates to a full-dot type graphic display device that is capable of displaying images.

Some systems use computers to process documents, drawings, etc. (hereinafter referred to as documents), and use a facsimile machine or equivalent device as a terminal, through which documents can be input and output to and from the computer. In such systems, information representing the contents of a document is converted into a video signal within the computer and stored in a storage device. The contents of the storage device are displayed on a graphic display device as required, allowing the operator to view an image of the document. A full-dot type graphic display device is used, which displays the image of a document made up of a collection of minute pixels.
It is now possible to display it faithfully.

The current practical limit for the number of pixels on one screen of this type of graphic display device using CRT is 1024 per horizontal scan. On the other hand, when a G-class facsimile reader is used as a document input terminal, the video signal has 2048 pixels per horizontal scan, so this video signal is sent to a CRT graphic display device. , only a portion (about 1/4) of the document image is displayed. Therefore, although the video is highly detailed, it is not possible to see the entire document.

An object of the present invention is to be able to display both a detailed image of a part of a document and an overview image of the entire document, and to display an arbitrary specified part of the overview image as a detailed image. An object of the present invention is to provide a graphic display device.

The present invention provides two systems of refresh memory,
A video signal that has been subjected to pixel reduction processing to match the number of pixels of the display device is written to one of the refresh memories, and a video signal that has not undergone such processing is written to the other refresh memory. The content is switched and displayed according to the operator's specifications, and while a video signal that has undergone pixel reduction processing is displayed, the range specified by the operator is displayed with the brightness changed, and the pixel reduction processing is performed. The display of the video signal that does not correspond to the specified range is performed for images belonging to this specified range.

Hereinafter, the present invention will be explained in detail with reference to the drawings. FIG. 1 is a conceptual diagram of a document processing system in which a graphic display device of the present invention is combined. In FIG. 1, 1 is a main processor, 2 is a main memory, 3 is a display control circuit, 4 is an auxiliary storage control circuit, 5 is a document input/output control circuit, and 6 is a video processor. These are interconnected by a data bus 7 to form one system.
This system is controlled by a main processor 1. The display control circuit 3 has a graphic display device 31, such as a CRT, under its control and controls it. Auxiliary memory control circuit 4
has the magnetic disk device 41 under its control and controls it. The document input/output control circuit 5 has a document input device 51 and a document output device 52 under its control, and controls them. The document input device 51 is a facsimile reader or a device equivalent thereto, and converts an image of an article on a document into a video signal consisting of a collection of minute pixels, and sends the video signal to the document input/output control circuit 5. It is given to The document output device 52 is a facsimile printer or a device equivalent thereto, which draws an image of the corresponding article on a document recording medium such as paper in accordance with the video signal given from the document input/output control circuit 5. It is.

A video signal of a document inputted from the document input device 51 via its control circuit 5 is temporarily stored in the buffer area of the main memory 2, and then subjected to compression processing etc. by the video processor 6. The data is stored in the magnetic disk device 41 via the auxiliary storage control circuit 4. The video signal stored in the magnetic disk device 41 is read out as needed, decompressed by the video processor 6, and then sent to the graphic display device 31.
Or output to the document output device 52,
Display or writing is performed respectively.
As the graphic display device 31,
A high-resolution full-dot type is used to faithfully display images of document articles, which are collections of minute pixels.

The smaller the pixels, the larger the amount of video signal, so a high-speed video processor is used to process it, ensuring immediacy of display on the graphic display device 31. .

In addition to video signals, the magnetic disk device 41 stores various data and programs including code signals, which are read out to the main memory 2 and used by the main processor 1 as needed. In addition, the graphic display device 31
It is also possible to graphically display not only images of articles in documents but also data processing results of the main processor 1. graphic
A keyboard is attached to the display device 31, and the operator can give various commands to the system by operating the keyboard. These are common to ordinary computer systems.

In such a system, graphic
The device of the present invention is used as the display device 31, and an embodiment thereof is shown in FIG.

In FIG. 2, 311 is a controller;
2 is a size switching circuit, 313 and 314 are refresh memories, 315 is a pixel reduction circuit, 316 is a parallel/serial converter, 317 is a display device such as a CRT, 318 is a cursor address register, and 319 is a cursor control circuit. be.

The refresh memory 313 stores a video signal whose pixels have been reduced by the pixel reduction circuit 315 in accordance with the display 317, and the refresh memory 314 stores a video signal whose pixels have not been reduced. These refresh memories 313,
314 is enabled to output either one by the output signal to the magnitude switching circuit 312, outputs the stored contents under the control of the controller 311, and displays it on the display 317 through the parallel/serial converter 316. give. Note that the controller 311
An operator's operation signal is applied to the size switching circuit 312 via a processing device through a keyboard or the like (not shown).

The pixel reduction circuit 315 is a type of processor that examines the dot pattern corresponding to the brightness and darkness of the pixels constituting the video signal, for example, examining four adjacent dots at a time, and divides these four dots according to the combination of their brightness and darkness. Then, the image is represented by one bright or dark dot. As a result, the number of pixels representing the image of the document is halved vertically and horizontally.
In other words, it is reduced to 1/4. Therefore, an image of the document at a scale of 1/2 is stored in the refresh memory 313 (FIG. 3a). Therefore, the 2048 pixels per horizontal scan of the G-class facsimile reader is reduced to 1024 pixels per horizontal scan, which is suitable for the pixels of a high-resolution full-dot CRT display. As a result, when the video signal from the refresh memory 313 is applied to the display 317, the entire image of the document can be displayed in a reduced size (FIG. 3b). However, this image has reduced resolution because the number of pixels has been reduced.

The other refresh memory 314 stores a video signal without pixel reduction, thereby storing a document image with a magnification of 1 (FIG. 3c). Therefore, when the contents of the refresh memory 314 are applied to the display 317, only a part of the document image is displayed in an enlarged form (the third
Figure d). This image has no pixel reduction, so the resolution remains the same as the G facsimile.

Therefore, by operating the size switching circuit 312, the operator can arbitrarily select either an overview screen with low resolution but showing the entire document image, or a fine screen with high resolution but only a part of the document image visible. You can see it at random. Since the video signals of both screens are held in respective refresh memories, the screens can be switched at high speed. When switching from the overview screen to the detailed screen, use the cursor to specify which part of the overview screen is to be displayed.

As shown in Figure 3b, the cursor is expressed as a surface cursor on the overview screen by making the area corresponding to the display part of the fine screen different in brightness from the surrounding area. Register 318 and cursor control circuit 319
is provided. The contents of the cursor address register 318 provide a reference point for cursor formation (for example, the upper left end point of a surface cursor), and can be set arbitrarily by the operator. The cursor control circuit 319 determines an address range for different brightness from the contents of the cursor address register 318 and the size of the wrinkle known in advance, and controls the brightness of the display 317 based on this. In this way, the cursor is displayed not as a mere dot but as a surface, which is convenient because the range to be viewed as a detailed screen can be clearly specified.

When switched to the detailed screen, controller 3
11 is a refresh memory 314 according to the switching signal and the contents of the cursor address register 318.
, and causes the display 317 to display the video corresponding to the range specified by the cursor.

As described above, the present invention provides two systems of refresh memories, one of which is written with a video signal that has been subjected to pixel reduction processing according to the number of pixels of the display, and the other refresh memory is written with A video signal that does not undergo such processing is written, and the contents of these refresh memories are switched and displayed according to the operator's specifications.
In addition, while displaying a video signal that has undergone pixel reduction processing, the range specified by the operator is displayed with different brightness, and when displaying a video signal that has not undergone pixel reduction processing, images belonging to this specified range are displayed. I made it.

Therefore, according to the present invention, it is possible to display both a detailed image of a part of a document and an overview image of the entire document, and to display any specified part of the overview image as a detailed image. A graphic display device that can display images can be realized.

[Brief explanation of the drawing]

FIG. 1 is a conceptual block diagram of a document processing system in which the apparatus of the present invention is combined, and FIG.
FIG. 3 is a conceptual block diagram of the embodiment of the present invention, and FIG. 3 is an explanatory diagram of the operation. 31...Graphic display device, 3
11... Controller, 312... Large/small switching circuit, 313, 314... Refresh memory, 3
15...Pixel reduction circuit, 316...Parallel/serial converter, 317...Display device, 318...Cursor address register, 319...Cursor control circuit.

Claims (1)

[Claims] 1. A full-dot type graphic display device having a display device with a smaller number of pixels than the number of pixels of a video signal per document,
A first refresh memory that stores the video signal per document, a pixel reduction circuit that reduces the pixels of the video signal per document in accordance with the pixels of the display, and the pixel reduction circuit that reduces the number of pixels. a second refresh memory for storing a video signal read out from the refresh memory, a magnitude switching circuit that enables output of the read contents of either one of these refresh memories based on an operator's operation, and the read contents of these refresh memories. a full-dot-shaped display that displays a cursor address register whose contents are set according to operator operations, and a cursor address register whose contents are similar to the range that can be displayed at one time on the display of the first refresh memory A range is set in the second refresh memory based on the contents of the cursor address register, and the range on the screen of the display device when the contents of the second refresh memory are displayed is set to another range. and a control circuit for displaying an image in a range corresponding to the range indicated by the cursor control circuit when the display device displays the contents of the first refresh memory. graphic display device.