JPS61223888A - Graphic generator - 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] Industrial Field of Application The present invention is suitable for use in equipment that is required to generate graphics with little jaggies (step-like edges), such as CAD systems and broadcast character graphics creation and transmission systems. The present invention relates to a suitable graphic generator.

BACKGROUND OF THE INVENTION First, the basic configuration of a graphic generator will be explained with reference to FIG. In the figure, reference numeral 1 denotes a graphic signal generating device, which is often configured around a CPU. 2 is frame memory,
Record the signal output from 1. Reference numeral 3 denotes a filter circuit such as a conical filter used to simultaneously read out a plurality of display unit pixels 6 on the frame memory and then output a weighted average signal of the signals to the display device 4.

Next, the operation of the above configuration will be explained. The graphic signal generated by the graphic signal generator 1 is recorded in the frame memory 2. At this point, there are jaggies at the boundaries of the figure, but after being weighted averaged with neighboring pixels by the filter circuit 3, the jaggies become less noticeable, and the display device 4
Shapes with less jaggies are displayed.

Explanation will be added to FIG. 3 regarding signal processing in the conventional frame memory 2 and filter circuit 3. The figure shows a partial range of the display pixel array on the frame memory 2, where 6 is the display pixel, 6 is read out from the frame memory 2 at a time, and the filter circuit 3 takes a weighted average. Display pixel 5 to be smoothed (P, ~P9
) (for example, nine) are shown. All of the values P1 to P contribute to the output of the filter circuit 3.

Problems to be Solved by the Invention However, in the configuration of the conventional example described above, although aliasing noise and jaggies can be reduced by taking a weighted average, mutual interference occurs between display pixels P1 to P9. As a result, the image becomes blurred, resulting in an image with low clarity.

SUMMARY OF THE INVENTION An object of the present invention is to provide a graphic generation device which eliminates the drawbacks of the conventional example and provides a screen with less jaggies and high clarity.

Means for Solving the Problems In order to achieve the above object, the present invention provides sub-pixels around display pixels that do not contribute to display but increase the amount of information when storing graphic signals in a frame memory. Also, when reading the contents of the frame memory,
It is configured to perform filtering by reading out each discretely arranged display pixel and taking a weighted average including surrounding sub-pixels.

Effect Since the present invention has the above-described configuration, the amount of information is increased by adding sub-pixels for filtering.
The weighted average reduces the jaggies. On the other hand, since the display pixels exist discretely, there is an effect that they do not interfere with each other due to the weighted average at the same time during the filtering.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 and 2. In Fig. 2, the difference from the conventional example is that frame memory 2a is used instead of frame memory 2.
The frame memory 21L will be explained with reference to FIG.

In the same figure, 6 is the display pixel (Pixel), e a is the range of the filter 3 at one time, and 7 is the subpixel (Subpi).
xel) is a point on the frame memory 2& that provides spatial information of the image but is not used as a display pixel.

Next, the operation will be explained. The graphic signal generated by the graphic signal generator 1 in FIG. 2 is stored in the frame memory 22L as shown in FIG.
P5) and eight sub-pixels 7 (Q1 to Q4, Q6 to Q,) are read out simultaneously, a weighted average is taken by the filter circuit 3, and the result is supplied to the display device 4 as an output. in this case,
Since the display pixel 6 and the sub-pixel 7 are not structural stops, the effect of reducing jaggies is not much different from the conventional example. However, the display pixels 50 included in the filter range 6a
Since the number of pixels is one at a time, mutual interference between the display pixels 6 does not occur, and therefore, no blurring of the image occurs. Instead, eight sub-pixels 7 are required for - display pixels, so the frame memory 2 corresponds to a certain range of the screen.
The number of elements of & is required to be four times as many, taking into account overlapping use.

The degree of provision of sub-pixels is not limited to the case shown in the arrangement of FIG. 1; if the number of display pixels is (an integer greater than or equal to 2), that is, MXN times.

Note that there is no difference in the method of storing information content between the display pixel 6 and the sub-pixel 7 between the conventional example and the embodiment, but the difference between the two lies in the method of reading out the information. For example, in FIG. 3, after reading out nine items centered on P5, the next reading is performed on nine items included in the filter range 8 centered on P6. On the other hand, in FIG. 1, the next nine readings centered on P5 are different in that they are performed on the next filter range 8a centered on every other P'5. In other words, this corresponds to the fact that the subpixel 7 of Q, to Q, does not become the center point when taking the weighted average. Therefore, in the case of the conventional example, the values of the nine display pixels 5 are all influenced when taking a weighted average, whereas in the above embodiment, the values of the display pixels 6 are separated by the sub-pixel 7. For example, display pixels P5 and P'5 in FIG. 1 will not be filtered at the same time, and there will be no interference between them.

Effects of the Invention As explained in the above embodiment, the present invention is configured so that sub-pixels that are not used for display and contribute only to the accumulation of graphic information are arranged around the display pixels of the frame memory, so that the filter circuit As a result of weighted averaging, the same jaggie reduction effect as in the conventional example can be obtained, but there is also the advantage that there is no mutual interference between display pixels, and therefore the spatial resolution of the image does not deteriorate.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the structure of a frame memory of a figure generator in an embodiment of the present invention, FIG. 2 is a block diagram showing the structure of the figure generator, and FIG. 3 is a frame diagram of a conventional figure generator. FIG. 2 is an explanatory diagram showing the configuration of a memory. 1...Graphic signal generator, 2a...Frame memory, 3...Filter circuit, 5.
...Display pixel, 6...Filter range, 7
・・・・・・Subpixel. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure ■ × ■ X ■

Claims (1)

[Claims] a graphic signal generator that generates a graphic signal; a frame memory that stores the graphic signal from the signal generator as a display pixel and a subpixel provided close to the display pixel;
A graphic generation device comprising: a filter circuit that reads the stored contents of the frame memory including the sub-pixel in units of the display pixel, takes a weighted average of the results, and outputs the result.