JPS5842090A - Image display - 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 The present invention is a so-called television monitor device in which image information consisting of gradation information for each pixel is sequentially fetched from a storage circuit or the like for each pixel, and predetermined display gradation information is added to the gradation information. The present invention relates to an image display device that converts the image into a display image that corresponds to the image and displays it.

When converting the gradation information of each pixel into display gradation information such as predetermined gradation information or color information and displaying it on a television monitor, display a certain part of the range of the gradation information of the pixel in the original picture information. Conventionally, it has been common practice to display images in association with the entire range of possible gradations, such as light and shade.

For example, the gradation value of the original iii salary information (the value of gradation information corresponding to the gradation will be referred to as "gradation value") is from 0 to 1.
023, and there are 64 gradation levels that can be expressed (displayed) in the display system (represented by gradation values 0 to 63), and the gradation value of the original image information is in the range of 500 to 627. If the gradation value of the original image is 499 or less, the gradation value of the displayed image is 0, and the gradation value of the original image 11O is 500 or more and 627 or less. Pixels whose original II image has a gradation value of 628 or more are displayed with a display gradation value of 64.

FIG. 1 shows an example of such a conventional image display device! The clock signal output from the oscillation circuit J is counted by a counting circuit 2, and a synchronization signal B8 for scanning a cathode ray tube for display on a television monitor (not shown) is generated. On the left side, address data ADt- for the original image information storage circuit 3, which stores the tone values of all pixels of the original image in advance, corresponds to the cathode ray tube scanning position.
An analog signal DAK is generated, reads out the gradation value data GD of each pixel, and outputs the gradation to the gradation conversion circuit 4.
Figure 2 shows an example of a specific configuration of the grayscale conversion circuit 4 in Figure 1. Memory circuit 3 shown
The gradation value data DDt which is the output of % D/A is read from the memory circuit 41 as the first position
A (digital/analog) converter 42 converts it into an analog signal D and outputs it. The contents of the memory circuit 41 are written in advance by a data processing device (not shown).

Conventional devices of this type have the above-mentioned configuration, and since the operation of the grayscale conversion circuit 4, that is, the conversion characteristics are constant within the entire display screen, the display screen is divided into multiple parts to display multiple Ij images on one screen. There was a problem when displaying.

Next, for example, the first one where the pixel gradation values are distributed from 0 to 1ooo
When displaying the image at the same time as the second image distributed from 0 to SO, if the operation of the grayscale conversion circuit 4 is set to match the first image and the pixel gradation value of 1000 is the maximum density, The second image can hardly display gradations.
Conventionally, in such cases, arithmetic operations are performed on the gradation value of the pixel (for example, the gradation value of the pixel in the second image is multiplied by t20).
Although it has been attempted to display both gljgI with the same conversion characteristics of the grayscale conversion circuit 4, the processing is complicated and the optimum display is not necessarily achieved. Moreover, this is not a preferable method because it damages the original data.

The present invention has been made against the background of the above-mentioned circumstances, i.
An object of the present invention is to provide an image display device capable of displaying each image with good display gradation even when displaying a plurality of images on a screen with greatly different gradation values. There is.

In other words, the feature of the present invention for achieving this purpose is to obtain the section information on the display screen and, based on the section information, display sections on the gray scale value to correspond to the tone value of the pixel. The goal is to make it possible to change it from time to time.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 3 shows the configuration of an embodiment of the present invention, and the oscillation circuit 1, counting circuit 2, and memory circuit 3 are substantially the same as those shown in FIG.

The discrimination circuit 5 is a circuit for determining which section on the screen the pixel currently belongs to is to be subjected to grayscale conversion and obtaining section information 8Gt, for example, as shown in FIG. 4, the display screen t-four sections A.

If B, C, and DK are divided into 2n Li elements in both the horizontal and vertical directions, then the address in the horizontal direction (X direction) and the address in the vertical direction (Y direction) are as shown in the table. This can be determined by the combination of M2R (Mo5t 51gn1ficant Blt ~most significant digit) of the address.

〈Table〉 Reference numeral 6 is a gray scale conversion circuit, and as shown in FIG. It consists of an A/D converter #2 similar to the D converter 42, and the above-mentioned discrimination circuit 5 determines which storage area of the storage circuit 61 is used.
The determination is made using the section information 8Gt that is determined from . For example, in the storage circuit C1, the format shown in FIG. 6 is set for each section A, B, C, l), and in the next storage area, a string of light gradation values according to predetermined conversion characteristics is stored. , and select the storage area from the section information 8GK. If you do this, you can store the floor for each display section on the screen despite the simple configuration. Since the conversion characteristics of tone information can be made different, all m
s can be displayed in an easy-to-see form with the optimum gradation, and since the original data of the gradation information is used as the tt, there is no need to lose all the original data.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can be implemented with various modifications without changing the gist thereof.

For example, the number of partitions on the display screen may be other than four, the discriminant formula of the discrimination circuit 50 for discriminating partitions can be appropriately selected according to the partition division method, and the partition information S of the grayscale conversion circuit 6
A known method other than the above-mentioned method can also be used for selecting the conversion characteristic according to C. Furthermore, in addition to dividing the display screen according to the number of displayed images, the conversion characteristics of each part are controlled by controlling the conversion characteristics of each part so that the same image can be divided into small parts, for example, shading correction etc. It is also possible to use it for the above non-uniformity correction. t gradation information #ilK! The same method can be applied not only to the case where the color is displayed in a similar manner, but also to the case where the hue is expressed with a modified gradation.

Also, store image information in the memory circuit in advance.
In addition to the case where f is read out and used for image display, it is also possible to carry out the same manner as described above also when all the display gradation information is made to correspond to the gradation information of image information inputted from the outside and used for display.

By incorporating the present invention as detailed above, even when displaying multiple images with greatly different pixel gradation value ranges on the same screen, it is possible to display each image with good display gradation. An image display device can be provided.

[Brief explanation of the drawing]

FIG. 81 is a block diagram showing the configuration of a conventional device example, FIG. The figures are the ninth figure, Figures 5 and 6, explaining the operation of the same embodiment.
Is the diagram a part of the configuration of the same embodiment? These are a detailed block diagram and memory map. DESCRIPTION OF SYMBOLS 1... Oscillation circuit, 2... Counting circuit, S... Memory circuit, 5... Discrimination circuit, 6... Grayscale conversion circuit, #1.
...Memory circuit, -2...A/D conversion circuit〇Figure 1 Figure 3 Figure 4 ・

Claims (1)

[Claims] In my display device, which sequentially captures image information consisting of gradation information for each pixel pixel by pixel and converts it into display image information in which the gradation information K and a predetermined display gradation are associated with each other for display, A discriminating circuit that determines which section on the display screen the entered pixel belongs to and outputs it as section information; and a discriminating circuit that converts the entered gradation information into a display gradation value for each pixel and performs the above discrimination. 1. An image display device comprising: a grayscale conversion circuit that selects display grayscale values corresponding to grayscale information in accordance with the partitions under the control of the circuit's partition information output.