JPS61238092A - Color image display unit - 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 Application Field] The present invention relates to a color image display device, and particularly to a color image display having a so-called multi-Q plane configuration in which a display image is displayed by superimposing a plurality of color screens. Regarding equipment.

[Summary of the invention]

The present invention provides a color image display device in which a display image is constructed by superimposing a plurality of color screens, in which each color is stored in a color memory that stores color information used within the color screen. A reference area that can be referenced on each screen?
At the same time, by making it possible to change the position of each reference area in memory, the degree of freedom in color selection can be fully expanded without increasing memory capacity or hardware configuration cost.

[Conventional technology]

In the case of a color image display device such as a color display device of a computer system, color information that directly specifies the display color is written in the memory that stores all the characters, graphic patterns, etc. that will be displayed, or in its attribute area. This method has the disadvantage that the number of colors that can be expressed is limited by the focus number of the color information, and color switching cannot be performed instantaneously.

In so-called video RAMs that store characters, graphic patterns, etc., there is a so-called color code for indirectly specifying colors. This function is also called a color bullet function, and the essence is a color memory that stores actual display color information corresponding to the above color code, a so-called color lookup function. The look-up table is fully accessed based on the color code read from the video RAM or the like, and the information sound of the color actually displayed is read out.

By the way, in a color image display device with a so-called multi-plane configuration in which a display image is formed by overlapping multiple color screens (or planes), the number of bits of the color m-code of each screen (plane) is are often different from each other.

For example, for a color code for a text screen that displays only alphanumeric characters, kana characters, etc., a few bits (for example, 4 bits) is practically sufficient, but for a graph ink screen that displays figures, pictures, etc. It is preferable that many coins can be displayed simultaneously, and for example, a color code of about 8 bits or more is desirable.

[Problem that the invention seeks to solve]

In the case of a color image display device with a multi-plane configuration in which the color code of each plane is different from each other, basically the maximum bit number (the above color lookup Φ table corresponding to the D color code) , and select a color with a smaller number of bits than this color code.
Regarding the code, it is necessary to use part or all of the look-up table permanently, or to provide a separate dedicated look-up table. However, the former lacks flexibility in table use, and the latter has the problem of increasing the burden on hardware.

In view of these problems, the present invention can fully expand the degree of freedom in table use, suppress the increase in hardware burden even when the number of planes increases, and allow the contents of lookup tables to be An object of the present invention is to provide a color image display device capable of instantaneously switching display colors without changing them.

[Means to solve all problems]

In order to solve all of the above-mentioned problems, the present invention provides a color image display device in which a color display image is formed by superimposing a plurality of color screens, in which a color to be displayed within the color screen is specified. It has a color memory in which color information for color selection is stored, and all reference areas for color selection corresponding to each color screen are provided in the above color memory, and within this color memory. The position of the above reference area of
It is characterized by having all the means to be able to change the color independently for each color screen.

[Effect]

Reference areas corresponding to multiple color screens are set in the color memory, and by changing the positions of these reference areas in the memory, the display colors on each color screen are changed. The switching is done.

〔Example〕

Preferred embodiments of the present invention will be described below with reference to all the drawings.

FIG. 1 shows an embodiment of the present invention, for example, an image 1 displayed on a CRT (cathode ray tube) display screen, etc.
0 has a so-called Le Malte frame structure, which is constructed by overlapping multiple color screens (planes).These color screens can be used, for example, to display characters such as alphanumeric characters and kana characters. A text screen 11.12 for displaying images and a graph ink screen 13 for displaying figures and pictures on the screen at a resolution of 640 x 400 dots, etc. are used.Here, the text screen 11,
12, for example, it is possible to specify a color for each character, and the color 〇 code is set to 4 pints; The color m-code is 8 bits in total. Then, each text screen 11.12
In this case, each of 116 colors can be displayed simultaneously, and in the graph ink screen 13, 256 colors can be displayed simultaneously.

The multiple color screens 11, 12, 13, etc.
Sequential screen numbers (plane numbers) are assigned.

It is possible to select and specify the one corresponding to this plane number from among the I recolor screens 11, 12, 13, etc.

Next, image information regarding the display contents of each of the color screens 11, 12, 13, etc. is stored in the image information memory 3. The format and storage format of the image information in this case can be any format except that at least color selection can be performed using a color code. That is, for example,
Regarding the GraphInk screen 13, normally, the color code for each dot or the ON/OFF status for each valley dot is stored in the GraphInk RAM or video RAM in the form of a bit map, and each of the above dots In the case of storing only ON/OFF for each display block, the color code for each predetermined display block is stored in a so-called attribute area in the RAM. For text screens 11 and 12, all character patterns read from a character ROM etc. may be written in the form of a bit map to the above-mentioned video RAM etc. Alternatively, characters and patterns read from a character ROM etc. may be written in a bit map form to the above-mentioned video RAM etc.
The code may be stored as it is, but at least color m-codes for selecting colors in units of each character or in blocks of several characters should be stored in the memory. do. The image information memory 3 consists of the above-mentioned graph ink RAM, text RAM, etc.0 When displaying an image, the read address and input from the address input terminal 1 are input to the image information memory 3. When the screen number information (or screen designation information) is given from the input terminal 2, the image information at the position specified by the readout address on the force surface is read out.This readout image information f'L7j The color code is sent to the adder 4.The adder 4 receives input from the offset memory 5 which outputs predetermined offset information (offset address) according to the screen number information from the terminal 2. This offset information and the above color code are added together and sent to a color memory (so-called color lookup ψ table) 6. Here, the color lookup table or color - The memory 6 has the entire structure as shown in FIG. 2, for example. In the example shown in FIG. Color information is stored, and each color information is sequentially assigned a color code corresponding to the address from 1001 to 'FF' in hexadecimal notation. By specifying all of these 8-bit color code, one word can be created. The color information of 1 is determined.
For example, a word consists of 12 bits and is divided into three areas of 4 bits each: LR (red), G (green),
It shows the intensity of B (blue), and by the combination of R, G, and B, one color out of 4096 colors can be specified, and the look amplifier table as a whole has 256 colors out of 4096 colors. It is now possible to display.

Since the color code for text screens 11, 12, etc. is 4 bits, the desired area within this area is It is possible to obtain color information by specifying all the words in .In this case, for each text screen 11, 12, etc., a predetermined 8-bit offset address Ni -N2, etc., is obtained from the offset memory 5. , this offset address 1'L, N2
etc., are added to the color codes of each text screen 11, 12, etc., to obtain the address (color code) for the lookup table shown in FIG. Therefore, for example, when the offset address is N1 for the first text screen 11, the look amplifier table in FIG. The reference area 21 of
Similarly, when the offset address for the second text screen 12 is N2, the corresponding second
The reference area 22 is the area of addresses N2 to N2+15 on the look amplifier table in FIG.

Then, by rewriting the offset information (offsect addresses) Ns, Nt, etc. for the screen number information stored in the offset Φ memory 5, the actual display for the color code of each text screen 11, 12, etc. You can instantly switch between colors.

Note that the lookup table may be accessed by adding the offset address to the color code on the graph ink screen 13 or the like. In this case, by digitally adding the 8-bit offset address and the 8-pint color code to obtain an 8-bit table access address, 256
The correspondence between color code and color information changes cyclically within the word range, and although the expression color is somewhat limited, it is possible to change colors instantly. .

Such an offset memory 5 can also be understood as a pointer memory or a pointer table that specifies and changes the position of each reference area corresponding to each color screen on the lookup table. can.

Further, the number of words of the color memory 6, which is a color look-a-nog table, is set to be larger than the t address space according to the focus number of the maximum color code among the plurality of color screens forming the display image 10. This makes it possible to switch colors with a higher degree of freedom in color expression.

That is, as shown in FIG. 3, if a color lookup table is used in which 1024 words of color information corresponding to a 10-bit address are stored, the table will be displayed corresponding to the graph ink screen 13, etc. It is possible to take four reference areas 23 that are independent from each other and have no overlapping parts.

Therefore, for example, as shown in FIG. 3, a reference area 23 is specified by the off-net address N3 of the lo pit, and within this area 23, 25
When six colors are specified, by changing the offset address N3 to another offset address N3 that has a difference of 256 or more [rewriting the offset memory 5], the reference area 23 A reference area 23 that has no overlap with the above 256 colors will be specified, and other 256 colors that are completely different or unrelated to the above 256 colors will be specified.
You can instantly change the color. In this case, it goes without saying that the degree of freedom in changing the colors of the text screens 11, 12, etc. is further increased.

In this way, the color information read out from the color memory 6, which is the color lookup table, is read out from the CR
A plurality of screens 11.12. Display image 10 as a superposition of ta, etc.? , displayed on a CRT screen, etc.

Information other than color codes, such as character codes and attributes, is read from the image information memory every once in a while. 0N-OF of each dot in one-sided method etc.
The F information, etc. is sent to the display interface 7 after being subjected to predetermined signal processing using a character ROM, etc., as necessary.
I will send it to you.

Note that the present invention is not limited to the embodiments described above, and in the embodiments, an independent display memory is provided for each plane (color screen). This example describes an example in which planes are synthesized and displayed using the image information memory that is available, taking into account the priority of these planes during display operation, but there is also an example in which the entire image actually displayed is stored as is. Note 1.1 The present invention can also be applied to a system in which plane numbers and color codes are also written at the same time when writing to this memory using ffi.

Furthermore, the types and number of multiple color screens, the number of bits of the color code, the number of words of the color memory (lookup table), the number of bits of one word, etc. are not limited to the numerical values of the above-mentioned embodiments. It's not something you can do.

〔Effect of the invention〕

According to the color image display device of the present invention, a shared color m-
Lookup O table (color〇memory)? Even though it is used, the degree of freedom in using the table has been greatly expanded, and it is possible to change colors instantly by rewriting offset memory, and the increase in the burden on the hardware is extremely small. It's over.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a diagram showing another example of a color lookup table in a color memory. 3... Image information memory 4... Adder 5... Offset-memory 6... Color memory (look assembly table) 10... Display image 11.12... Text screen 13-- Graph ink screen

Claims (1)

[Claims] A color image display device that forms a color display image by superimposing a plurality of color screens has a color memory that stores color information for specifying the color to be displayed within the color screen, and each color A reference area for selecting a color corresponding to each screen is provided in the color memory, and the position of the reference area in the color memory can be changed independently for each color screen. A color image display device comprising: