JPH03296092A - image display device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention enables documents containing a mixture of characters, figures, images, etc.
The present invention relates to an image display device for displaying images on output devices such as display devices and printing devices.

[Conventional technology]

Conventional image display devices are simultaneously equipped with a bitmap memory for processing image information and a textmap memory for processing text information, and when displaying image information, the data stored in the bitmap memory is read out and displayed. death,
When displaying text information, the data stored in the text map memory is read out and displayed, thereby obtaining images with optimal display quality for each.

In addition, when displaying using outline information representing the outline of an image, bitmap information with the inside filled in is generated from the outline information, which is first stored in a bitmap memory and then displayed.

[Problem to be solved by the invention]

In the past, the ability to draw characters, figures, etc. using outline information was not very high, but in recent years there has been a demand for higher quality of displayed characters, figures, etc., and technologies such as outline fonts have become commonplace, so outline information Due to this, the frequency of drawing letters, figures, etc. has increased. For this reason,
The conventional display method, in which outline information is expanded into bitmap information and then displayed, has a slow processing speed and has placed a heavy burden on the system.

SUMMARY OF THE INVENTION An object of the present invention is to improve display processing speed using outline information, and to provide an image display device capable of displaying each of outline information, text information, and image information in the most suitable manner.

(Means for solving all!) The image display device according to the present invention stores outline information representing the outline of characters, figures, images, etc. to be displayed on the screen, and reads out the stored outline information in units of scan lines. , an edge map memory that sets the output to "1" with a logic "1" signal of one scan line, switches the output to "0" with the next logic "1" signal, and outputs outline information as image data. , memorizes the character code of the text information to be displayed simultaneously on this screen,
It is equipped with a text map memory that reads and outputs the image data of the character corresponding to the character code line by line when reading the character code, and outputs the output of the edge map memory and the output of the text map memory by overlapping them. Configure.

Furthermore, it is further equipped with a gray map memory that stores gray codes representing the gradation of characters, figures, images, etc. displayed on the screen for each display pixel, and reads out and outputs the stored gray codes for each scan line. The output of the map memory, the output of the text map memory, and the output of the gray map memory are configured to be output in a superimposed manner.

[Operation] In this configuration, the outline information stored in the edge map memory is read line by line in accordance with the display timing on the output device, and is read out for each data “1” by a flip-flop connected to the output side. It is inverted and output as bit image data.

In addition, the text data stored in the text map memory is read out by addressing the bit image data stored in the character/figure generator, line by line and dot by dot according to the display timing on the output device. Output as image data.

The gray code stored in the gray map memory is also read out line by line and output in accordance with the display timing on the output device.

Each piece of data thus output is superimposed by an OR gate, converted into an analog signal by a DA converter, and output.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of an image display device according to the present invention. In the following description, a case will be described in which a CRT display device is used as an output device.

In this embodiment, three memories, a text map memory 2, an edge map memory 3, and a gray map memory 4, are connected to an address bus Ba and a data bus Bd connected to a processor unit 1. A memory controller 5 for controlling is connected. Further, a character/figure generator 6 in which bit image data of each text is stored in correspondence with the text map memory 2 is connected to the address bus Ba.

The text map memory 2 stores text data indicating the codes of characters, figures, etc. to be displayed on the display, and the size of the displayed text is determined by the character/figure generator 6.
It is specified by bit image data of each text stored in .

For example, the alphabet rAJ is represented by 16 x 16 bit matrix data, as shown in Figure 2, where the shaded part corresponds to the data "D", the blank part corresponds to the data "0", and each line contains 2 bytes of data. Consists of.

This image data is read byte by byte to the dot shifter 7 under the control of the memory controller 5, and then output.

The edge map memory 3 stores contour information (edge data) of the image displayed on the display screen. Edge data is data that indicates the change point of data from white to black or from black to white in the scanning direction on the display screen. Set it to “1” and set the same dot as the previous dot as data rO.
This is special data set to J. The edge data output from the edge map memory 3 is sent to a flip-flop 8 which receives data "1" and inverts its output state, and is converted into focused image data and output.

The gray map memory 4 is a memory with a bit map structure that stores the gray code representing the gradation of the image displayed on the display in units of dots on the display screen.
It is configured to express 16 gradations using a bit gray code.

The memory controller 5 controls the memories 2 to 4 described above, generates horizontal and vertical synchronizing signals Hs and Vs for the CRT display device, counts dots in the horizontal direction and counts lines in the vertical direction, and controls each memory. Generates address data and timing data necessary for control. The dot clock DC output from the memory controller 5 is supplied to the dot shifter 7, flip-flop 8, gray map memory 4 and DA converter 10 as a clock signal. Further, the horizontal and vertical synchronizing signals Hs and Vs are outputted to the CRT display device via buffers lla and llb, of which the horizontal synchronizing signal Hs is supplied to the flip-flop 8 as a reset signal. Furthermore, blank data BD! ! The signal is supplied to the D/A converter 10, and the output is set to black level during the blanking period.

The output of the dot shifter 7, the output of the flip-flop 8, and the output of the gray map memory 4 are each input to a DA converter 10 via an OR gate 9, converted to an analog signal, and output to a display device (not shown). Ru.

In this configuration, when the processor unit 1 issues a command to display (alphabeso) rABcJ at the upper left of the screen of the display device, as shown in FIG. Data representing heads rAJ and rBJrCJ is stored as text data.

Next, the bit image data of the alphabet rAJ, rBJ, rCJ stored in the character/figure generator 6 is dot-shifted one byte at a time using the text data in the text map memory 2 as an address in accordance with the display timing on the display screen. Each dot is output as image data.

In this case, first, the first byte of bit image data corresponding to the alphabet rAJ is sent to the dot shifter 7, and the 8-bit data of this first byte is read out using the dot clock DC. Then the alphabet rAJ
Then, the first byte and second hide of alpha head rBJ are set and read, and then the first byte and second hide of alpha vent "C" are read in the same way. When each data on the first line is read out, next, each data on the second line is read out. That is, the alphabet rAj,
The data in the third and fourth bytes of rBJ and rcJ are read out in the same manner as in the case of the first line described above.

The edge data stored in the edge map memory 3 is also read out line by line in accordance with the display timing on the display screen, and the data "1" is read out by the flip-flop 8.
'' and then converted to bit image data and output. Since the edge map memory 3 uses a dual port memory for video RAM, a dot shifter is not necessary, and each dot is output in accordance with the dot clock DC. However, a cycle is generated to update the shift register inside the dual port memory on a line-by-line basis.

Similarly, the gray code stored in the gray map memory 4 is read out 4 bits per line by the dot clock DC in synchronization with the display timing on the display screen. Again, since a dual port memory for video RAM is used, no dot shifter is required.

Each piece of data output in this way is superimposed by the OR gate 9 and input to the DA converter 10, and the analog signal S
Output as out. Furthermore, when blank data BD is input to the DA converter 10, since it is a blanking period, the output becomes a black level and there is a period in which no image can be output on the display screen.

FIG. 4 is a timing chart roughly showing the operation of signals in each part. According to this timing chart, the output signal Se from the flip-flop 8 changes depending on the edge data ED, which is the output signal of the edge map memory 3.
The next data after data “1” of Edge Data ED “
It can be seen that the part corresponding to the dot before ``1'' has become ``1''. As a result, the OR outputs Sd1 to Sd4 with the gray data Sgs to Sg4 of this part are all "
1'', and this part becomes the highlight of the output signal 5out to the display device, and the image written by the edge superimposed on the output image can be seen as an actual image.

Similarly, the text bit image output signal St corresponding to the text map memory 2 is also
'', the output signal 5out of that part becomes the highlight, and the text image can be seen superimposed on the output image.

In the above-mentioned embodiments, a case has been described in which a CRT display device is used as the output device, but the present invention is not limited to this, and the same effects can be obtained even if a printer device is used.

〔Effect of the invention〕

According to this invention, outline information of characters, figures, images, etc. to be displayed on one screen is stored in an edge map memory,
This stored outline information is read out in units of scan lines, switched for each data "1", and outputted as bit image data, so it is possible to improve the display processing speed using outline information, and
In addition to edge map memory, it also has text map memory, gray map memory, etc.
It becomes possible to display a document containing a mixture of images and the like at high speed and with high quality using the most suitable method.

FIG. 4 is a timing chart showing the operation of signals in each part.

2...Text map memory, 3...Edge map memory, 4...Gray map memory, 5...Memory controller, 6...Character/figure generator, 7...Dot shifter, 8...・Flip flop, 9-・OR
Gate, 10...DA converter.

Claims (3)

[Claims] (1) Outline information representing the outline of characters, figures, images, etc. to be displayed on the screen is stored, this stored outline information is read out in units of scan lines, and the output is set to "1" with a logic "1" signal for one scan line. 1", and the output is switched to "0" with the next logic "1" signal, and the edge map memory outputs the above outline information as image data, and the character code of the text information to be displayed simultaneously on the above screen. and a text map memory that reads out and outputs image data of a character corresponding to the character code line by line when reading this character code, and overlaps the output of the edge map memory and the output of the text map memory. An image display device characterized by outputting images together. (2) Outline information representing the outline of characters, figures, images, etc. to be displayed on the screen is stored, this stored outline information is read out in units of scan lines, and the output is set to "1" with a logic "1" signal for one scan line. 1", and the next logic "1" signal switches the output to "0", and the edge map memory outputs the above outline information as image data, and the edge map memory that outputs the above outline information as image data, and the characters, figures, images, etc. to be displayed on the above screen. A gray map memory stores a gray code representing a gradation in units of display pixels, and reads out and outputs the stored gray code in scan line units, and the output of the edge map memory and the output of the gray map memory are connected to each other. An image display device characterized by outputting images in a superimposed manner. (3) Outline information representing the outline of characters, figures, images, etc. to be displayed on the screen is stored, this stored outline information is read out in units of scan lines, and the output is set to "1" with a logic "1" signal for one scan line. 1", and the output is switched to "0" with the next logic "1" signal, and the edge map memory outputs the above outline information as image data, and the character code of the text information to be displayed simultaneously on the above screen. a text map memory that reads and outputs the image data of the character corresponding to the character code line by line when the character code is read out; A gray map memory stores a code in each display pixel, and reads out and outputs the stored gray code in each scan line, the output of the edge map memory, the output of the text map memory, and the gray map memory An image display device characterized in that the output is superimposed on the output of the image display device.