JPH02224578A - Screen display device - Google Patents

Abstract

PURPOSE:To attain easy-to-see display through the identification even when a character color and its background color are the same and to allow the display device to easily and flexibly cope with the color preferred by the user by providing a chroma signal generating circuit to a video signal generating circuit. CONSTITUTION:An internal chroma signal generated by a chroma signal generating circuit 179 provided to a video signal generating circuit 18 is outputted to an internal mode circuit 171 and the chroma signal generating circuit 70 to activate the circuit 171 or the like to output a mixed chroma signal on a display device. Then an internal chroma signal and an internal brightness signal or the like are generated by controlling the circuit 18 with a display control circuit based on an output from a display data memory and a display character memory or the like and background color information from the display control register. That is, a relevant potential is selected from a potential representing each character color and each background color to set the brightness level of the background color and the chroma amplitude level smaller than the relevant character color when the character of the same color as the background color is displayed, the identification is facilitated and the device copes with a preferred color.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a screen display device that displays characters and patterns such as channel numbers in broadcast images displayed on a display device such as a cathode ray tube. .

[Prior art] Fig. 6 shows Mitsubishi Electric Edane Vol. 62 No. 2
・1988rTV on-screen character/pattern display control LS
I.

As shown in M50455-xxxsPJ.

1 is a block diagram showing the configuration of a conventional screen display device of this type, which is composed of - LSIs. In FIG. 6, 1 is a display oscillation circuit to which the oscillation output of the π-type LC oscillation circuit 1a is supplied, 2 is a timing generator that generates various timings using the signal oscillated by the display oscillation circuit 1, and 3 is a timing generator for this. Each input terminal 3 is connected to a microcomputer (not shown) for controlling the output of the timing generator 2 and the screen display device.
8 to 3c are input control circuits for inputting control data (commands and character codes for display on/off, etc.), 4 is a data control circuit, 5 is an address control circuit, and 7 is to be displayed on a display device. A display data memory that stores code data of characters and patterns and control data such as their R, G, and B color information and blinking information, and is composed of a RAM.

Reference numeral 8 denotes a display character memory which stores character patterns to be displayed in the font configuration shown in FIG. 7, and is composed of a ROM.

6 is a display control register for latching display control commands such as display position information and background color information among the outputs of the input control circuit 3; 9 is a terminal 9a;

A sync signal switching circuit selectively outputs either the horizontal or vertical sync signal of the video signal supplied to 9b or the horizontal or vertical sync signal generated internally; 10 counts this sync signal; H counter; 11 is a display position detection circuit for detecting the display position of characters, patterns, etc. on the display device based on the output of the H counter 10 and the display position information of the display control register 6; 12 is the display position detection circuit; Based on the output of 11, display data memory 7
a read address control circuit that outputs a read address of
Reference numeral 13 denotes a display control circuit, which outputs the output of the display character memory 8 inputted via the shift register 14 to control information from the display control register 6, color information for each character from the display data memory 7, and a display position detection circuit. Display control is performed according to the output of 11. Reference numeral 15 denotes an oscillation circuit for generating a synchronizing signal to which the oscillation output is supplied to the oscillation element circuit 15a, and numeral 16 denotes a timing generator for generating a synchronizing signal, which are used to generate internal synchronizing signals for the NTSC system and the PAL system. 17 is a video mixer that mixes an internal video signal with an external video signal and outputs the result; 21 is a blinking circuit. This screen display device is composed of the above circuits, - display control circuit 1
The output of 3 is the timing generator 1 for synchronizing signal generation.
6 and a video mixer 17, and the video mixer 17 outputs a composite video signal via a CVIDEO terminal 17a. Further, the display control circuit 13 outputs R, G, B color signals, etc. via terminals 13a to 13f.

Next, the operation will be explained. The input control circuit 3 processes control data inputted from a microcomputer or the like through terminals 3a to 3c, causes a display control register 6 to latch commands such as display control, and displays character codes and the like as display contents. data memory 7. During display, the character code stored in the display data memory 7 accesses the display character memory 8 as output data, and the display character fonts output in parallel from the character memory 8 are sent to the display control circuit 1 via the shift register 14.
Enter to 3. Here, the display data memory 7 is composed of a total of (a+b).C bits, where one word is (.a+b) bits and the number of displayed characters is C. on the other hand,
In the display character memory 8, as shown in FIG. 7, one font is made up of (JIXm) bits, and there are n characters of the types.

Moreover, the timing at the time of display is determined by inputting a synchronization signal from an external video signal to the synchronization signal switching circuit 9.

This synchronization signal is counted by the H counter 10, the position of the displayed character is determined by the display position detection circuit 11 based on this count value and display position information of the display control register 6, and the position of the display character is determined by the read address control circuit 12 based on this output. The display character memory 8 is accessed by reading out the contents of the data memory 7. The display control circuit 13 synchronizes the display character output with an external video signal, controls the display according to the contents of the display control register 6, outputs it, and supplies it to the video mixer 17.

Note that the synchronizing signal generation oscillation circuit 15 is the oscillation element circuit 1
5a, it is possible to generate a synchronization signal of the NTSC system or PAL system, and this switching is performed by the signal from the N/P terminal 15b, thereby outputting 4fsc or 2fsc oscillation, and the timing generator 16 for generating the synchronization signal outputs oscillation of 4fsc or 2fsc. Since a synchronizing signal is generated, display on the TV screen is possible even when there is no signal. However, fsc is the color subcarrier,
In the NTSC system, it is 3.58 MHz, and in the PAL system, it is 4.43 MHy.

In addition, the video mixer 17 allows NTSC and P
It is possible to generate an AL type composite video signal and to superimpose it onto an external composite video signal. The composite video signal has character level (LECHA), external composite video input (CVIN), blanking level (LEBK),
The six signals of background carrier color signal input (RSIN), color burst input (CBIN) and sync chip level are switched and synthesized using an analog switch, and the CVIDEO terminal 17
Output from a. That is, depending on the display content, a composite signal generated inside the video mixer 17 as shown in FIG. 8, that is, an internal video signal in which a luminance signal and a carrier color signal (chroma signal) are superimposed, is generated. , the text color and background color are set, and this internal video signal is mixed with an external video signal to create the above CVID.
By outputting to a TV's cathode ray tube or the like via the EO terminal 17a, data input from a microcomputer or the like can be displayed along with images. Here, one background color can be selected from among eight colors for the entire display area of characters and patterns.

[Problem to be solved by the invention] In recent years, TVs and VTRs have rapidly become more diverse, multifunctional, and have improved operability, and there is a demand for easy viewing and high image quality for displaying channels, VTR operating status, etc. It has been done. However, conventional screen display devices are configured as described above, and if the font color of each character or pattern can be changed for each character against an arbitrary background color, the color of one character and the background color will be the same. There was a problem that the characters and patterns could not be distinguished and were difficult to see. Furthermore, since the amplitude level of the chroma signal was uniquely determined, there was a problem in that it was not possible to produce the desired color according to the user's request.

This invention was made to solve the above-mentioned problems. Even if the text color and the background color are the same, it is possible to distinguish between them and obtain an easy-to-read display. The object of the present invention is to obtain a screen display device that is flexible and easily adaptable.

[Means for Solving the Problems] A screen display device according to the present invention includes a video signal generation circuit including a setting means for individually setting the chroma amplitude level of a text color and a text background color for each color.

The amplitude level of the chroma of the text background color is set to be smaller than the amplitude level of the chroma of the corresponding text color.

[Operation 1] In the screen display device of the present invention, the setting means for individually setting the chroma amplitude level of the character color and its background color for each color is used to set the chroma amplitude level of one character color for each color in advance. By reducing the chroma amplitude level by a certain amount, even if the text color and the background color are the same, the text can be distinguished because the saturation is different. Further, the amplitude level of the chroma of the reference character color can be adjusted to suit the user's preference.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. Components that are the same as those in FIGS. 6 to 8 are designated by the same reference numerals, and the description thereof will be omitted.

In FIGS. 1 and 2, 18 is a video signal generation circuit that generates each internal video signal, and 19 is a port output control circuit that outputs various signals from port output terminals 19a to 19f. The video signal generation circuit 18 is shown in FIG. 3(a).
), and a chroma signal generating circuit 179 that generates an internal chroma signal of a chroma component which is the amplitude of a carrier color signal of a color par signal as shown in FIG. A luminance signal generation circuit 180 that generates a signal, and a composite signal generation circuit 18 that generates an internal composite signal as shown in FIG.
1, a selector 182 that is controlled by the display control register 6 via the display control circuit 13 and selects either the internal luminance signal or the internal composite signal, and a clamp level generation circuit 183 that generates a clamp level. Although omitted, it also includes generation circuits for generating a color burst signal, a sync tip level, a pedestal level, an own level, a black level, etc. necessary for generating an internal video signal. Here, the chroma signal generation circuit 179 and the luminance signal generation circuit 180 correspond to the 5-VH8 system, which obtains a high-quality display by inputting the chroma signal and the luminance signal in a separated state to the display device. These signals can be generated internally.

On the other hand, the video mixer 17 includes a chroma signal generation circuit 70 that mixes the internal chroma signal and clamp level with an external chroma signal and outputs the mixture via the C0UT terminal 17b, and a chroma signal generation circuit 70 that mixes the internal chroma signal and clamp level with an external chroma signal and outputs the mixture through the C0UT terminal 17b, The composite video signal generating circuit 71 mixes the luminance signal from the external device or the internal composite signal and each level signal with an external composite signal and outputs the mixed signal through the CVIDEO terminal 17a. The chroma signal generation circuit 70 includes an external mode circuit 170 that receives and outputs a chroma signal of a video signal from the outside via the CIN terminal 17d, and an internal mode circuit 170 that outputs an internal chroma signal generated by the chroma signal generation circuit 179. It consists of a mode circuit 171 and a clamp level circuit 172 that outputs the clamp level generated by the clamp level generating circuit 183. The composite video signal generation circuit 71 also includes a white mode circuit 173 that sets the color to single white, and an external mode circuit that takes in a luminance signal or a composite signal of a video signal from the outside via the CVIN terminal 17c and outputs it. 174, a black mode circuit 175 that sets the color to monochromatic black, an internal mode circuit 176 that outputs the internal luminance signal generated by the luminance signal generation circuit 180 or the internal composite signal generated by the composite signal generation circuit 181, and the It consists of a clamp level circuit 177 that outputs the clamp level generated by the clamp level generation circuit 183, and a sync tip level circuit 178 that sets a sync tip level. The mode circuits and level circuits described above are composed of analog switches, etc., and a specific circuit selected by the output of the display control circuit 13 is turned on in a time-sharing manner, and the mixed signal is sent to the CVIDEO terminal 17a and the C0UT terminal 17b.
is output to the display device.

Each generation circuit 179.1 in the video signal generation circuit 18
80, 181, and 183, as shown in FIG. Connected level setting resistor 179a
, 180a, 181a, 183a are provided one or more depending on each specification. Chroma signal generation circuit 17
9 and level setting resistors 179a and 181a provided in the composite signal generation circuit 181 are shown in FIG.
As shown in +C+, desired potentials are extracted from the positions corresponding to the upper and lower limits of the chroma amplitude level of the character color for each color (six colors excluding white and black), and a certain amount of amplitude is extracted from each of them. The potentials of the six corresponding character background colors are extracted from the lowest level position, and the upper and lower limit values are alternately switched at predetermined timings where the phase with the color burst signal is controlled. Signals as shown in FIGS. 3(a) and 8 are generated with different amplitude levels for one character color and character background color, and one of the colors is output from the display control circuit 13. It has become. Note that the internal chroma signal generated by the chroma signal generation circuit 179 has the same amplitude level for yellow and blue, cyan and red, and green and magenta, as shown in FIG.
They are commonly taken out. Furthermore, since the internal composite signal generated by the composite signal generation circuit 181 is a signal in which the ROMA signal and the luminance signal are superimposed, as shown in FIGS. The chroma amplitude level is set smaller, and the brightness level is also set smaller.On the other hand, the level setting resistor 180a provided in the brightness signal generation circuit 180
As shown in Fig. 4 (bl), a desired potential is extracted from a position corresponding to the luminance level of the character color for each color, and from each of them - a fixed amount, that is, a fixed amount from a position on the ground v0 side. The potential of the corresponding character background color is taken out, and this generates a signal as shown in Figure 3 (bl) in which the brightness level is different between the character color and character background color, and One of the colors is output as an output.Furthermore, the clamp level generation circuit 183 includes a level setting resistor 18.
Only one 3a is provided, and a desired clamp potential is taken out from a position of a clamp level according to the user's request. In addition, in each of the above-mentioned video signals, the potential (ffi) corresponding to the font color is set to meet the user's request, and a video signal of a magnitude (amplitude) corresponding to the user's request is generated. The font color and background color as well as each level, that is, the potential, according to the user's request, as described above, can be changed in a flexible ROMization process by a program that is performed at any step in the manufacturing process of the LSI. In other words, each of the level setting resistors 179a to 183
a is P provided on a silicon substrate as shown in FIG.
``PMO8 type transistor Tri consisting of a diffusion region,
An NMO3 type transistor Tr2 consisting of an N diffusion region, a resistor section 80 formed between each of the transistors Tri and Tr2, and a Δ1 wiring 82a laminated on the resistor section 80 with an interlayer insulating film 81 interposed therebetween.

82b. These resistors 179a to 183a obtain contact points 83a and 83b through a program-based flexible ROM margin process in the LSI manufacturing process, and are contacted at these positions to connect AJI wiring 82a and 82b.
The contact point 83a is formed by connecting the resistor section 80 and the contact point 83a.

The divided potential can be taken out at 83b, so that each level can be arbitrarily varied in accordance with the user's request during the LSI manufacturing stage.

Next, the operation will be explained. The video mixer 17 and the video signal generation circuit 18 are controlled by the display control circuit 13 based on the contents of the display control register 6 and the like. First, if the composite video signal to be output to the first display device is a composite signal, the selector 182 selects the component 1-signal generation circuit 181, outputs the internal composite signal to the internal mode circuit 176, and then outputs the internal composite signal to the internal mode circuit 176. When the internal mode circuit 176 and the like are turned on in the internal mode circuit 71, a mixed composite video signal is outputted to the display device via the CVIDEO terminal 17a. Next, when outputting a 5-VH8 system signal, the brightness signal generation circuit 180 is selected by the selector 182, and the internal mode circuit 176 outputs the internal brightness signal.
In the composite video signal generation circuit 71, the internal mode circuit 1
76 and the like, the mixed luminance signal is output as a composite video signal to the display device via the CVIDEO terminal 17a. In addition, the chroma signal generation circuit 1
The internal chroma signal generated in 79 is sent to internal mode circuit 171.
By turning on the internal mode circuit 171 and the like in the chroma signal generation circuit 70, a chroma signal that is mixed is output to the display device via the C0UT terminal 17b. The internal chroma signal, internal luminance signal, and internal composite signal are 1 background color information 9 from the display control register 6.
RGB output 9 for each character from display data memory 7
The video signal generation circuit 18 is controlled by the display control circuit 13 based on the font output of the character memory 8 and the output from the display position detection circuit 11, and each character color and each background shown in FIG. It is generated by selecting the appropriate potential from among the color potentials. Therefore, even if a character with the same color as the background color is displayed, the background color has a higher luminance level and chroma amplitude level than the character color. is set small, so it is displayed with lower brightness and saturation than the text color, making it possible to clearly identify the text.In addition, the text color level and clamp level of these internal video signals are determined by the user. Depending on the request, a video signal that matches the external video signal and each level of the display device is output.Thereby, it is possible to correspond to the user's favorite color.

In the above embodiment, a device corresponding to the 5-VH8 system is shown, but a similar effect can be obtained even if the device includes only the composite signal generating circuit 181.

In addition, in the above embodiment, the background color is smaller than the character color for both the brightness level and the chroma amplitude level, so that it can be more clearly identified. A desired color can be obtained, and the intended purpose of the present application can be achieved.

[Effects of the Invention] As described above, according to the present invention, the video signal generation circuit is provided with a setting means for individually setting the chroma amplitude level of the text color and text background color for each color, and the text background color The amplitude level of the chroma is set smaller than the amplitude level of the chroma of the corresponding text color, so even if the text color and text background color are the same color, it can be distinguished, providing an easy-to-read display, and making it possible to match the user's preference. It has the effect of being able to respond flexibly and easily to colors.

[Brief explanation of the drawing]

FIG. 1 is an overall block diagram of a screen display device according to an embodiment of the present invention, and FIG. 2 is a block diagram of a video signal generation circuit and a video mixer of this embodiment. Figure 3 +a), (bl is a diagram showing the chroma signal and luminance signal, Figure 4 (al to (dl) is an equivalent circuit diagram showing the main part configuration of the video signal generation circuit, Figure 5 is the LSI of Figure 4. A sectional view, FIG. 6 is an overall block diagram of a conventional screen display device, and FIG.
The figure shows the structure of one font of the display character memory, and FIG. 8 shows the composite signal. DESCRIPTION OF SYMBOLS 1... Display oscillation circuit, 2... Timing generator, 3... Input control circuit, 4... Data control circuit, 5... Address control circuit, 6... Display control register, 7... ...Display data memory, 8...Display character memory, 9...Synchronization signal switching circuit, 1o...H
Counter, 11... Display position detection circuit, 12... Read address control circuit, 13... Display control circuit, 14
Shift register, 15... Oscillator circuit for generating a synchronizing signal, 16... Timing generator for generating a synchronizing signal. 17... Video mixer, 18... Video signal generation circuit, 19... Port output control circuit, 21... Blinking circuit, 70... Chroma signal generation circuit, 71...
...Composite video signal generation circuit, 179...Chroma signal generation circuit, 180...Brightness signal generation circuit, 181...
- Composite signal generation circuit, 182...Selector. 183...Clamp level generation circuit, 179a-18
3a...-Level setting resistor' (setting means). In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Figure 3 (a) Figure 3 (1)) Color agent Masuo Oiwa (and 2 others) Kyu 4I ¥1 ("fQJ) 179a ~ 1B + a Nireher Sma fixed moon) also mine jI 7 figure Figure 8 Shinnona, A

Claims (1)

[Claims] In a screen display device that displays characters, patterns, etc. on a display device such as a cathode ray tube, there is provided an oscillation circuit that generates signals that serve as a reference for various timings, and a system that generates various signals based on the oscillation signals of the oscillation circuit. A timing generator that generates timing signals, an input control circuit that accepts and processes control signals from an external control circuit such as a microcomputer, and a control circuit that processes characters and patterns to be displayed on the display device. A display data memory that stores data such as codes and their color information, a display character memory that stores fonts of characters displayed as the display contents, and display position information and background colors that are input from the input control circuit. a display control register that holds control data such as information, a synchronization signal switching circuit that inputs a synchronization signal for a video signal to be displayed on the display device, and a display position that counts this synchronization signal and detects the display position of the display device. a detection circuit, a video signal generation circuit that generates an internal video signal, a video mixer that mixes the internal video signal with an external video signal and outputs the mixture to a display device, the display control register, a display data memory, and a display. a display control circuit that controls the video signal generation circuit and the video mixer to display display content at a predetermined position of the display device based on the output of the character memory and the display position detection circuit, and the video signal generation circuit includes: The present invention is characterized by having a setting means for individually setting the amplitude level of the chroma of the text color and the text background color for each color, and setting the amplitude level of the chroma of the text background color to be smaller than the amplitude level of the chroma of the corresponding text color. screen display device.