JPH04320295A - Gray scale display controller of monochrome display panel - Google Patents

Abstract

PURPOSE:To make a clear-contrast gradational display by converting color image data into gray scale brightness data when color video software is monitored on the monochrome display panel (plasma, liquid crystal, or EL display, etc.). CONSTITUTION:A exclusive gray scale brightness data memory 11 which matches the characteristics of the display panel is provided, address data for accessing the memory is generated according to the color image data, and gray scale brightness data stored in the address is read out of the memory 11 and stored in a gray scale image memory 14 corresponding to the dot address of the color image data; and the data is outputted as a digital monochrome video signal and displayed on the display panel 18.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention converts color image data into grayscale luminance data when monitoring color video software in a monochrome display panel device (plasma display, liquid crystal display, EL display, etc.). The present invention relates to a grayscale display control device that enables gradation display with clear contrast.

0002

[Prior Art] Conventionally, monochrome display panel devices mainly display information such as characters, figures, or waveforms in two gradations of white or black. It was unsuitable for displaying continuous multi-tone information. That is, since it is difficult to produce a high-brightness panel device in a monochrome display panel device, it is difficult to express brightness differences in multi-gradation expression. Furthermore, due to its light emitting mechanism, it is not good at displaying continuous brightness like a monochrome CRT.

However, in recent years, due to the diversification of display information, color information has become mainstream, and in monochrome display panel devices, color information must be expressed accurately in monochrome. Therefore, it is conceivable to supply a conventional monochrome CRT luminance signal in which a Y luminance signal is calculated from an RGB color signal to a monochrome display panel device, but in this case, as described below, the gradation expression will be unnatural. There were drawbacks such as.

FIG. 2 shows a conventional example of forming a monochrome CRT luminance signal from digital color image data. Serial color image data is received by an interface 1 from a CPU (not shown), and converted into parallel data by an image signal generator 2 to generate a digital video signal, a synchronization signal, and a clock signal, respectively. Based on these signals, one frame of digital video signal is separated into R data, G data, and B data and temporarily stored in the color image memory 3. Each data R, G, B output from the color image memory 3 is sent to the D/A converter 41.
, 42 and 43, the signals are converted into analog color video signals and output. This analog color video signal is applied to a color CRT. The R data, G data, and B data output from the color image memory 3 are input to the Y signal calculator 5, which adds and synthesizes each R data, G data, and B data at a predetermined ratio, respectively, to create a monochrome digital video. It is considered to be a luminance signal. This digital video luminance signal is temporarily stored in the luminance signal image memory 6 and then output. Further, the synchronization signal is output after passing through a delay logic 7 for timing adjustment.

[0005]

[Problem to be Solved by the Invention] Since the digital video luminance signal formed and output as described above is calculated as a luminance signal by the Y signal calculator 5 under certain conditions based on the color signal, Although it is suitable as a luminance signal, for monochrome display panel devices with different emission mechanisms, the luminance range is too wide or the luminance signal level and emission luminance characteristics do not match, so a clear monochrome image is displayed. There were drawbacks such as the fact that it was difficult to The present invention has been made in view of the above-mentioned prior art, and an object of the present invention is to enable color information to be expressed in monochrome with clear gradation in real time in a monochrome display panel device.

[0006]

[Means for Solving the Problems] A gray scale display control device of the present invention is a gray scale display control device for displaying with gray scale brightness in a display panel device that performs monochrome display, and is capable of controlling color image information. grayscale luminance data storage means for storing the grayscale luminance data with conversion characteristics suitable for the display panel device; memory access means for forming an address signal corresponding to the luminance based on the color image information, and reading gray scale luminance data from the gray scale luminance data storage means using the address signal; a grayscale image memory for storing grayscale luminance data in synchronization with the inputted color image information dots, and applying the output of the grayscale image memory to the display panel device to store the grayscale luminance data in synchronization with the inputted color image information dots. The feature is that monochrome display is performed according to the data.

[0007]

According to the present invention, a dedicated grayscale luminance data storage means for a monochrome display panel device is provided, and color image information (that is, RGB data) is stored.
Create address data for accessing the luminance data storage means from , read out the grayscale luminance data stored at the address, store it in the same grayscale image memory address as the dot address of the color image, and store it at the same grayscale image memory address as the dot address of the color image. Since it is output as a digital monochrome video signal, color image information can be changed to grayscale luminance data with characteristics suitable for monochrome display panel devices, and a clear grayscale image can be obtained. Furthermore, by appropriately setting the characteristics of the grayscale luminance data storage means, it is possible to extremely easily obtain an optimal grayscale image even for motochrome display panel devices with different luminance characteristics. It is possible.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained below based on embodiments shown in the accompanying drawings. In FIG. 1, board A is an analog color video signal processing circuit section for obtaining an analog color video signal based on digital color image data from a CPU, and has the same configuration as the conventional example shown in FIG. That is, the interface 1 receives serial color image data from the CPU, and the image signal generator 2 converts the data into parallel data to generate a digital video signal, a synchronization signal, and a clock signal, respectively. The R data, G data, and B data stored in the color image memory 3 based on these signals are converted into respective analog color video signals by D/A converters 41, 42, and 43.

Board B is a digital monochrome video signal processing circuit section for obtaining a digital monochrome video signal for display based on digital color image data from the CPU. Board C is a memory circuit unit related to board B. The combination of boards B and C corresponds to a grayscale conversion device according to the invention. To explain the circuits of boards B and C, first, the second interface 8 receives a digital color video signal given from the interface 1, and outputs an address signal, a data signal, and a control signal based on this. This interface 8 sequentially outputs the digital color video signal for each dot as the data signal, generates an address signal for each dot, sequentially outputs this as the address signal, and outputs the data signal for each dot sequentially. The control signal is output in synchronization with the output timing of the signal and the address signal.

The data signal is applied to the data input of the data latch 9, and according to the control signal, the latch 9
latched to. The address signal is applied to the data input of the address latch 15 and is latched into the latch 15 according to the control signal. The data latch 9 latches the digital color video data added to the data input separately as R data, G data, and B data. The upper 5 bits of R data, G data, and B data excluding the least significant bit are latched and output. This is to compress an excessively wide brightness range and obtain a digital monochrome video signal with an appropriate brightness range.

ROM access logic 10 includes latch 9
5 bits of R data, G data, and B data given from ROM 11 are input, and an address signal for accessing the luminance data ROM 11 is generated and output. Brightness data RO
M11 stores optimal dedicated brightness data for the monochrome display panel device, and reads and outputs the optimal brightness data according to the access address. Note that in the ROM access logic 10, the 15-bit access address may be generated by simply combining the 5-bit R data, G data, and B data, or, for example, the R data may be 31%, the G data may be 59% %, B data 10%, etc., and by adding these weights, a multi-bit address signal may be generated. In the former case, 1
It is possible to select 32,768 types of luminance data using a 5-bit access address, and a grayscale image can be constructed by combining these.

The luminance data output from the luminance data ROM 11 is sent to the gradation divider 12, and the gradation selection means 1
After being divided according to the gradation selection data given from 3, it is input to the gray scale image memory 14. The gradation selection means 13 outputs arbitrary gradation selection data according to the gradation suitable for the video software at that time, the observer's visibility, the viewer's preference, etc., and thereby enables adjustment and selection of the gradation. Make it. For example, based on 16 gradations, this is adjusted to 8 gradations, 4 gradations, or the like.

The grayscale image memory 14 temporarily stores the luminance data provided from the gradation divider 12. The address signal from the address latch 15 is input to the address calculator 16, and the address signal output from the address calculator 16 is input to the gray scale image memory 1.
4 to specify the write address. One frame of brightness data output from the gray scale image memory 14 is given to the monochrome display panel device 18 together with a synchronization signal passed through the delay logic 17. The display panel device 18 displays an image in accordance with the provided grayscale luminance data and synchronization signal.

It is assumed that the brightness data ROM 11 stores brightness data corresponding to the monochrome display panel device to be used. For example, various ROMs are available, such as those that store brightness data compatible with plasma display panel devices, those that store brightness data that correspond to liquid crystal display panel devices, and those that store brightness data that corresponds to EL display panel devices. By replacing this ROM, the brightness data ROM 11 is obtained. Alternatively, various ROMs may be installed and used selectively with a switch. It goes without saying that the gradation divider 12 may be omitted and the expression gradation may be selected by replacing the luminance data ROM 11.

[0015]

As described above, according to the present invention, a dedicated grayscale luminance data storage means for a monochrome display panel device is provided, and the luminance data storage means is accessed from color image information (that is, RGB data). Create address data for the image, read out the grayscale luminance data stored at the address, store it in the same grayscale image memory address as the dot address of the color image, and output it as a digital monochrome video signal. This makes it possible to change color image information into grayscale luminance data with characteristics suitable for monochrome display panel devices.
Clear grayscale images can be obtained. Also,
By appropriately setting the characteristics of the grayscale luminance data storage means, or by adopting dedicated luminance data storage means for monochrome display panel devices with different luminance characteristics, it is possible to The effect is that an optimal gray scale image can be obtained extremely easily for a chrome display panel device.

[Brief explanation of drawings]

FIG. 1 is a circuit block diagram showing one embodiment of the present invention.

FIG. 2 is a circuit block diagram showing an example of a conventional method.

[Explanation of symbols]

1... Interface, 2... Image signal generator, 3... Color image memory, 4... DA converter, 5... Y signal calculator, 6... Luminance signal image memory, 7... Delay logic, 8
...Second interface, 9...Data latch, 10...
ROM access logic, 11...Brightness data ROM, 1
2... Gradation divider, 13... Gradation selection means, 14... Gray scale image memory, 15... Address latch, 16... Address calculator, 17... Delay logic.

Claims (1)

[Claims] 1. A grayscale display control device for displaying with grayscale luminance in a display panel device that performs monochrome display, the device for changing luminance data based on color image information into luminance data for grayscale. A grayscale luminance data storage means that stores luminance data for the grayscale with conversion characteristics suitable for the display panel device, and an address signal corresponding to the luminance based on the input color image information. memory access means for reading out gray scale luminance data from the gray scale luminance data storage means according to the address signal; and a grayscale image memory for storing data in synchronization with the dots of the display panel, and the output of the grayscale image memory is applied to the display panel device to perform a monochrome display according to the grayscale luminance data. Gray scale display control device.