JPS5848101B2 - Zukei Hatsuseisouchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a figure generation device that digitally generates figures or characters under the control of a processing device and outputs them as a video signal.

In a conventional figure generator that forms and outputs figures in a digital image memory according to control instructions from a central processing unit, the capacity of the digital image memory is determined by the following factors.

(1) the resolution of the terminal display, the number of dots corresponding to the band, (2) the number of bits necessary to represent the luminance gradation per dot, and (3) in the case of color, the image memory function for each primary color.

Therefore, the digital image memory occupies a large proportion in a graphic generation device for producing color images with gradations, making the device expensive.

An object of the present invention is to improve the quality of output images within the limited capacity of the digital image memory described above when using a home television receiver as a terminal display.

Since the band of home television receivers is limited to 4 MHz, the resolution in the horizontal direction is determined by this.

Furthermore, in the case of color images, the I and Q signals are band-limited to 1.5 MHz and 500 kHz, respectively, in the NTSC system.

For this reason, the number of horizontal bits of each color signal component of the digital image memory is determined.

However, the display position accuracy improves as the number of bits increases, and the naturalness of the screen also improves accordingly.

For the above reasons, it is desirable to provide a digital image memory with a degree of precision in order to output a somewhat natural screen.

For example, if one pixel for Y signal is 140+1 seconds and the display position accuracy is 70+1 seconds, the display position accuracy is 140+1 seconds.
The naturalness increases compared to the case of 1 second.

In this case, the number of horizontal bits of the image memory is 2.
twice as necessary.

An object of the present invention is to utilize the robustness of an image memory having this robustness for further other information.

In the present invention, in order to improve display position accuracy, a digital image memory is given a degree of precision, or a digital image memory having a degree of precision is given meaning to a specific pattern in this memory, and gradation information is provided here. , carries hue information.

The amount of information that can be stored in the memory varies depending on the length of the memory, that is, the ratio of the size of one pixel to the display position accuracy of the display.

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an example of the configuration of a graphic generator A, in which an interface section 1 receives control information 9 from a central processing unit (not shown), and sends it to a graphic generator 2 to generate a graphic.

The graphics generated by the graphics generator 2 are stored at designated addresses in the R, G, and B digital memories 3, 4, and 5.

After all the information for one screen is stored in the digital memories 3, 4, and 5 corresponding to each color of R, G, and B, the reading circuit 6 reads out the information along the scanning line, and the arithmetic unit 7 converts the data. It is output as a video signal 10 via a video signal converter 8.

The configuration of the digital image memories 3, 4, and 5 described above is
As shown in the figure.

Figure 2 shows the configuration of one page of digital image memory as displayed on the terminal, where horizontal lines 21 indicate vertical dot boundaries, vertical lines indicate horizontal dot boundaries, and broken lines indicate horizontal dot boundaries. .

Both the solid line 22 and the broken line 23 are valid for the display position in the horizontal direction, but the smallest picture element has a size indicated by the blacked out area 24.

Therefore, a hatched portion 26 is taken as an example of a figure surrounded by a solid line 25 represented by dots.

FIG. 3 shows an example of a pattern actually stored in the digital image memory.

When storing pattern 31, two modes are created and the states of modes 32 and 33 are assigned to each.

In the case of this embodiment, these two modes apply to two types of luminance of one primary color signal.

Therefore, when the gradation is 1, it is written in the mode 32 format, and when the gradation is 2, it is written in the mode 33 format.

The readout circuit 6 shown in FIG. 1 detects a 010 pattern, rewrites 010 to 011 as the pattern, and sends a signal for modulating the output level to the video signal converter 8.

The video signal converter 8 determines the level of the pattern signal sent to it using the level modulation signal and outputs it.

In this embodiment, since the digital image memory has 83 R, G, and 83 planes, it is possible to express 3 gradations for each color, a total of 27 types of colors, without adding any particular gradation memory.

As described above, the present invention provides a digital image memory sufficient to indicate a display position with an accuracy finer than one pixel, and is useful when reducing unnaturalness caused by digitizing figures. By effectively using this memory, it is possible to increase the gradation of colors and brightness.

This allows for increased functionality per price.

[Brief explanation of the drawing]

1 to 3 each show an embodiment of the present invention, in which FIG. 1 is a configuration diagram of a figure generator, FIG. 2 is an explanatory diagram of the configuration of the digital image memory shown in FIG. 1, and FIG. The figure is an explanatory diagram of patterns stored in a digital image memory. Explanation of symbols, 1... Input interface section, 2
...Graphic generator, 3...Digital image memory for R (red), 4...Digital image memory for G (green), 5...B (blue) digital image memory, 6...Memory reading unit, 7...
...Signal calculation section, 8...Video signal conversion section, 9
...Input control information, 10...Output video signal, 21...Vertical picture element boundary, 22...
・Horizontal picture element boundary, 23...Horizontal picture element boundary, 24
...Minimum picture element, 25...Display target pattern, 26...Dotted pattern, 31...
...Dot pattern, 32...Memory pattern 1, 33...Memory pattern 2.

Claims (1)

[Claims] 1. In a figure generation device having a digital image memory that is divided into units finer than the minimum pixel size when displayed on a terminal display, the display position accuracy and horizontal line length accuracy can be improved by the memory of the device, and at the same time Multi-gradation or multi-hue production can be achieved by utilizing redundant parts of the memory to obtain multiple modes identified by special storage patterns in the image memory and applying the corresponding gradation or hue to each mode. A figure generator characterized in that it is capable of displaying images.