JPH0573020A - Display controller - Google Patents

Abstract

PURPOSE:To obtain a display controller where display colors which are different in respective screens can be set as a picture display controller which can simultaneously display plural screens in color. CONSTITUTION:A readout control signal is given to storage means 11A, 11B where the image data different from each other are stored in every specified timing and an image control means 12 is provided which outputs the plural image data corresponding to a certain display position on the screen of an external display means. This system is also provided with a selection and discrimination means (circuit) 13 which discriminates what image data is used to perform display at a display position according to the content of the outputted image data and outputs a selection signal, and a selection means (selector) 14 which selects and outputs any of the inputted image data based on the selection signal. Then, color palette means 15 stores palette data assigned to the respective image data and outputs the palette data at the display position based on the image data and the selection signal outputted from the selection means. Then, the palette data is converted to a display signal and outputted by a conversion means 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display control device, and more particularly to an image display control device capable of simultaneously displaying a plurality of screens in color.

[0002]

2. Description of the Related Art FIG. 3 shows the basic configuration of a conventional display control device.
The block diagram shown is shown. The display control device 30 is preset
Image in the window that is the specified area (window image
Window data, which is the image data for displaying
TA D_WAnd the image outside the window (background screen) is displayed.
Background data D that is image data for _BRespectively
It has two VRAMs 31A and 31B to remember.
The image controller 32 controls read-out at predetermined timings.
Signal S_RCTo output two VRAMs 31
On the screen of the display 37 from each of A and 31B
Window data (n bits) at a certain display position
And background data (n bits) are output to the selector 34.
It On the other hand, the selection determination circuit 33 has the window data D
_WIs input, and the input window data D_WIs transparent
Determine the color, that is, whether the background screen is displayed.
Separately, the select signal S is sent to the selector 34._SIs output. Yo
More specifically, window data D_WIs "0"
If it means a transparent color, the window data D_WBut
When it is “0”, the selection determination circuit 33 determines that the selector 34
Background data D_BSelect signal S for selecting_STo
Output and window data D_WIf it is not "0"
Window data D in the selector 34_WFor choosing
Select signal S_SIs output. Selector 34 selects
Signal S_SBased on the window data D_WOr back
Scene data D_BIs output selectively, but in the above example,
Window data D_WExcept when is 0
Window data D_WOutput to the color palette 35
Becomes The color palette 35 supports a plurality of display colors.
The palette data is stored in advance and entered.
R (Red), G (Green),
Display data D for each B (Blue)_R, D_G, D_B(Each m bit
Output) to the D / A converter 36. D / A converter
The data 36 performs digital / analog conversion, R, G,
Display data D of B_R, D_G, D_BDisplay signal S_DDConversion to
And output to the display 37.

As a result, on the display 37, the image represented by the window data D _W is superimposed and displayed on the image represented by the background data D _B. In this case, image superposition means window data D _W.
It is indicated that the image indicated by the window data D _W is (priority) displayed on the screen of the display, except for the transparent portion of the image indicated by.

In the case of the above example, the number of displayable colors CN and the number of display colors SCN that can be simultaneously displayed on the display screen are shown.
Respectively, CN = 2 ^3m SCN = 2 ⁿ . More specifically, the number of bits of image data input to the color palette is n = 4 bits, R is output,
If the number of bits of each display data of G and B is m = 4 bits, CN = 2 ^3x4 = 4096 SCN = 2 ⁴ = 16, and 16 colors out of 4096 colors can be displayed simultaneously. The 16 colors are the same on the window screen and the background screen.

[0005]

In the above-mentioned conventional display control device, only the same display color can be used on the background screen and the window screen, so that inconvenience occurs such that the display becomes difficult to see. Was there.

Therefore, an object of the present invention is to provide a display control device capable of setting different display colors for each screen in an image display control device capable of simultaneously displaying a plurality of screens.

[0007]

In order to solve the above problems, the present invention provides a storage means for storing image data different from each other, and a read control signal to the storage means at a predetermined timing, and the storage means externally. Image control means for outputting a plurality of image data corresponding to a certain display position on the screen of the display means, and any image data of the image data at the display position based on the contents of the plurality of output image data. Discriminating means for discriminating whether or not to perform display and outputting a selection signal of image data, and selecting means for selectively outputting any one of the plurality of image data from the storage means based on the selection signal. , Palette data indicating a plurality of display colors assigned to each of the image data is stored in advance, and the image data output from the selecting means is stored. And a color palette means for outputting the palette data at the display position based on the selection signal, and a converting means for converting the palette data output from the color palette means into the display signal and outputting the display signal. To do.

[0008]

According to the present invention, the image control means gives a read control signal to the storage means at every predetermined timing, and a plurality of image data corresponding to a certain display position on the screen of the external display means from the storage means. Is output to the discriminating means and the selecting means. The discriminating means discriminates which image data of the image data is used for display at the display position based on the contents of the plurality of output image data, and selects the image data selection signal by the selecting means and the color palette. Output to the means. The selection means selectively outputs any one of the plurality of image data from the storage means to the color palette means based on the selection signal. The color palette means outputs the palette data at the display position to the converting means based on the image data output from the selecting means and the selection signal. The conversion means converts the palette data output from the color palette means into the display signal and outputs the display signal to an external display means.

As a result, the external display means performs display by using different palette data for each image data, and it is possible to perform display using more display colors.

[0010]

EXAMPLES Next, examples will be described with reference to FIGS. First Embodiment FIG. 1 is a block diagram showing the basic configuration of the first embodiment.

The display control device 10 has a predetermined area set in advance.
The image (window screen) in the window that is the area
Window data D which is image data for_WAnd
And an image for displaying the image outside the window (background screen)
Background data D which is image data _BTwo to remember each
It has VRAMs 11A and 11B of
The controller 12 controls the read control signal S at a predetermined timing._RCTo
By outputting the two VRAMs 11A and 11B,
Each display position on the screen of the display 17
Window data D in_W(N bits) and background
Data D_B(N bits) is output to the selector 14.
On the other hand, the selection determination circuit 13 has the window data D_WBut
Is entered. This input window data D_WIs transparent
Bright color, that is, whether the background screen is displayed
The selection determination circuit 13 makes the determination, and the selector 14 and the color
The select signal is output to the pallet 15. More specifically
Is the window data D_WIs a transparent color when is "0"
If it means, the selection determination circuit 13 is
Background data D in the selector 14 when data = "0" _WTo
Select signal S for selecting_SELOutput the window
Data D_WIf ≠ "0", the window is displayed in the selector
Data D_WSelect signal S for selecting _SELOutput
To do. Therefore, the selector 14 outputs the select signal S
_SELBased on the window data D_WWhen = “0”
Window data D except_WTo the color palette 15
It will be output. The color palette 15 is used in this embodiment.
In case of 2 ^{n + 1}Has a storage capacity of Word,
Bullet window data D_WFor multiple display colors about
2 corresponding palette dataⁿWord data and background data
D _BData corresponding to multiple display colors for
2ⁿStored for each word, input image
Data and select signal S_SELBased on the display date
TA D_R, D_G, D_BIs output. More specifically, the input
The image data is the window data D_WIf
Is the window data D_WFor multiple display colors about
Display the display data for each R, G, B by referring to the corresponding palette data.
Data D_R, D _G, D_BD / A convert (each m bits)
Output to the data 16. Also, the input image data is the background
Data D_B, The background data D_Babout
R, referring to the palette data corresponding to multiple display colors
Display data D for each G and B_R, D _G, D_BThe D / A converter
Output to the data 16. The D / A converter 16 is a digital
R / G / B display data
D_R, D_G, D_BDisplay signal S_DConvert to display
Output to (i) 17. This allows the display 17
Is background data D_BIn the image shown by,
TA D_WThe image shown in will be superimposed and displayed.
It

In the above example, the displayable color number CN ₁ , the display color number SCN _{w which} can be simultaneously displayed on the window screen on the display screen, and the display color number SCN _{b which} can be simultaneously displayed on the background screen are CN respectively. = 2 ^3m SCN _w = 2 ⁿ SCN _b = 2 ⁿ . More specifically, the number of bits of image data input to the color palette is n = 4 bits, R is output,
If the number of bits of each display data of G and B is m = 4 bits, CN = 2 ^3x4 = 4096 SCN _w = 2 ⁴ = 16 SCN _b = 2 ⁴ = 16, and the window screen has 16 colors out of 4096 colors and the background The screen can also display 16 out of 4096 colors simultaneously. The 16 colors that can be displayed simultaneously are different between the window screen and the background screen, and 32 colors (16 + 16 colors) for both screens.
Simultaneous display is possible.

[0013]Second embodiment FIG. 2 is a block diagram showing the basic configuration of the second embodiment.
The display control device 20 has a predetermined area that is a preset area.
Image for displaying the image in the window (window screen)
Window data D that is image data_WAnd windows
Image data for displaying an external image (background screen)
Background data D _BVRAMs 1 for storing each
1A and 11B, the image controller 18
Readout control signal S at every predetermined timing_RCTo output
From each of the two VRAMs 11A and 11B
Wi-Fi at a certain display position on the screen of the display 17
Window data D_W(N bits) and background data D
_B(N bits) is output to the selector 14. Same as this
Sometimes the image controller 18 outputs the output window
TA D_WDisplay based on which screen data
Select signal S indicating whether or not_SELSelector 14 and
Output to the color palette 15. Ie window
Data D_WA transparent color is meant when = "0".
Then, the image controller 18 determines that the window data D_W
If “= 0”, the background data D is displayed in the selector 14._BTo
Background data D to display_BSelect
Select signal S for_SELIs output. Also win
Dough data D_WIf ≠ “0”, the selector 14
Window data D_WSelect signal S for selecting_SEL
Is output. Therefore, the selector 14
S_{SE L}When window data = "0" based on
Window data D except _WTo the color palette 15
It will be output. The color palette 15 is used in this embodiment.
In case of 2^{n + 1}Has a storage capacity of Word,
Bullet window data D_WFor multiple display colors about
2 corresponding palette dataⁿWord data and background data
D_BData corresponding to multiple display colors for
2ⁿStored for each word, input image
Data and select signal S_SELBased on the display date
TA D_R, D_G, D_BIs output. More specifically, the input
The image data is the window data D_WIf
Is the window data D_WFor multiple display colors about
Display the display data for each R, G, B by referring to the corresponding palette data.
Data D_R, D_G, D_BD / A convert (each m bits)
Output to the data 16. Also, the input image data is the background
Data D_B, The background data D_Babout
R, referring to the palette data corresponding to multiple display colors
Display data D for each G and B_R, D_G, D_BThe D / A converter
Output to the data 16. The D / A converter 16 is a digital
R / G / B display data
D_R, D_G, D_BDisplay signal S_DConvert to display
Output to (i) 17. This allows the display 17
Is background data D_BIn the image shown by,
TA D_WThe image shown in will be superimposed and displayed.
It

In the above example, the displayable color number CN ₁ , the display color number SCN _w that can be simultaneously displayed on the window screen on the display screen, and the display color number SCN _b that can be simultaneously displayed on the background screen are CN, respectively. = 2 ^3m SCN _w = 2 ⁿ SCN _b = 2 ⁿ . More specifically, the number of bits of image data input to the color palette is n = 4 bits, R is output,
If the number of bits of each display data of G and B is m = 4 bits, CN = 2 ^3x4 = 4096 SCN _w = 2 ⁴ = 16 SCN _b = 2 ⁴ = 16, and the window screen has 16 colors out of 4096 colors and the background The screen can also display 16 out of 4096 colors simultaneously. The 16 colors that can be displayed simultaneously are different between the window screen and the background screen, and 32 colors (16 + 16 colors) for both screens.
Simultaneous display is possible.

In each of the above embodiments, the VRAM for storing the window data D _W and the background data D _B is separately provided, but a VRAM having a large storage capacity is used and the storage area is divided and used. It is also possible to do so.

In each of the above embodiments, at the same time,
I explained only the case where there are two screens displayed, but the same
Even if there are multiple screens that are displayed on three or more sides,
The invention of can be applied. In this case, multiple
When displaying screens at the same time, give priority to which screen
The priority of display is given in advance for each screen
The highest priority among multiple screens to be displayed
The screen with the highest rank shall be displayed. Therefore, the
In the embodiment according to the first aspect of the invention, the selection determination circuit 13
Select the screen with the highest priority among multiple screens and
It may be configured to output a recto signal. Also,
In the second embodiment of the invention, an image controller
18 determines which screen has the highest priority among multiple screens
However, it may be configured to output the select signal. This
Different for each display screen by configuring
The display color can be used, and the bit of image data
If the number is n bits and the number of simultaneous display screens is k,
Maximum number of display colors that can be displayed on C _maxIs the full screen, C_max= 2ⁿXk. In this case, the color palette 15 has 2^{n + k-1}Wa
It has a storage capacity of Word (Word),
2 palette data corresponding to multiple display colors for eachⁿ
It must be configured to store words.

[0017]

According to the present invention, the discriminating means discriminates which of a plurality of storage means is to be displayed based on the image data stored and outputs a selection signal so that the color pallet means are mutually connected. Palette data indicating a plurality of display colors assigned to different image data are stored in advance, the pallet data at the display position is output based on the image data and the selection signal output from the selecting means, and the pallet is converted by the converting means. Since the data is converted into a display signal and output to the external display unit, the external display unit can display using different palette data for each image data, and display using more display colors can be performed. It can be carried out.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a first embodiment.

FIG. 2 is a block diagram showing a basic configuration of a second embodiment.

FIG. 3 is a block diagram showing a basic configuration of a conventional display control device.

[Explanation of symbols]

10 ... Display control device 11A, 11B ... VRAM 12 ... Image controller 13 ... Selection determination circuit 14 ... Selector 15 ... Color palette 16 ... D / A converter 17 ... Display 18 ... Image controller 20 ... Display control device _DW ... Window data D _B ... Background data D _R , D _G , D _B ... Display data S _SEL ... Select signal S _RC ... Read control signal S _D ... Display signal

Claims (1)

[Claims] 1. Storage means for storing mutually different image data, and a plurality of read control signals are provided to the storage means at predetermined timings, and a plurality of storage locations corresponding to certain display positions on the screen of an external display means are provided from the storage means. An image control unit that outputs image data, and a selection signal of the image data that determines which image data of the image data is used to display at the display position based on the contents of the plurality of output image data. And a selection unit that selectively outputs any one of the plurality of image data from the storage unit based on the selection signal, and a plurality of display colors assigned to each of the image data. The palette data shown is stored in advance, and is displayed at the display position based on the image data output from the selecting means and the selection signal. That a color palette unit for outputting the palette data, the display control device, characterized in that the pallet data outputted from the color palette unit provided with a conversion means for outputting converted into the display signal.