JPH09114441A - Method and device for generating gray font from outline data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display a character, which is constituted complicatedly, beautifully and faithfully to a character shape by finding the gradation value of a gray font in every square frame from the area ratio of the size of a painted-out area and the size of each square frame. SOLUTION: A division processing part 3 sections outline data on a character stored in an outline data storage part 2 with n<2> square frames formed in n×n (n: integer) meshes. A closed loop area generation part 9 connects the intersections of the sectioned square frames and outline data to generate a closed loop area (painted-out area). An area ratio calculation part 10 finds the ratio of the size of the closed loop area to the size of the square frame. A conversion processing part 12 determines the gray gradation of each square frame by contrasting the area ratio with numerals in a gray gradation signal conversion table stored in a gradation value storage part 11. Then the outline data are converted into a gray gradation signal based upon the gradation value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention divides a character into n ² square frames formed by a mesh of n × n (n is an integer), and displays each square frame with one gradation representing gray shades. By doing so, the present invention relates to a gray font generation method and apparatus for displaying an entire character in multiple shades of gray.

[0002]

2. Description of the Related Art Japanese is usually written by combining syllabary characters Katakana and Hiragana and ideographic characters Kanji. And the kanji currently used are:
From simple structures that can be written in one stroke to complex structures that have more than 30 strokes in total, such kanji with a large number of strokes can be accurately displayed on a display such as a word processor or computer CRT. To display the output,
At least 36 x 36 dots per character, preferably 4
8x48 dots were needed.

However, since a conventional display device such as a CRT has a relatively coarse resolution, as described above, 36 ×
36 dots or 46 x 46 dots characters are too big,
There was a problem that many characters could not be displayed at one time.
When these characters are displayed with, for example, 12 × 12 dots, the character shape is changed or the characters are crushed, so that they cannot be displayed accurately.

Recent display devices such as CRTs have a high resolution, and it has become possible to display a large number of characters of 36 × 36 dots at a time. However, these characters can be displayed, for example, at 12 × 12 dots. If you try to display with, the glyphs will not be able to be displayed accurately due to being collapsed.

Further, when a character of recent outline data is converted to a binary bit map font, that is, when a so-called rasterizing process is performed, if the mesh dividing the character into a plurality of square frames is rough, the shape of the character is likely to be crushed.

That is, the rasterizing process is as shown in FIG.
For example, the outline data shown in FIG. 20 is expanded into a 12 × 12 mesh as shown in FIG. 20, and a square frame (hereinafter referred to as a block) is divided by the mesh corresponding to the outline data.
And a block that does not correspond to outline data,
The blocks corresponding to the outline data are filled in as shown in FIGS. 21 and 22, so that 12 × 12 mesh raster data (binary bitmap font) as shown in FIG. 23 is obtained. The coarser the mesh, the more faithfully the glyphs cannot be displayed. Therefore, it was supported by having a bitmap font with a fine mesh.

However, in the CRT display, the above-mentioned 2
It is said that the gray font, which displays the character data by converting the fine mesh as described above into a grayscale signal representing the grayscale of a plurality of gradations for each block, has better visibility than the value bitmap font.

FIG. 24 is a diagram showing the difference in visibility between the case where the outline data of the character "skill" is represented by the binary bitmap font and the case where it is represented by the gray font of 4 gradations.

Hereinafter, based on FIG. 25 to FIG. 29, "technique"
A method of generating a four-tone gray font of the character "" from outline data will be described. In this conventional example, description will be made assuming that one block divided by the flag mesh described later is composed of one dot.

FIG. 25 shows the outline data of the Japanese style of the kanji called "skill". The kanji called "skill" is shown in FIG.
It is expanded to 24 × 24 mesh (576 blocks) as shown in. Then, a flag is set for each block corresponding to the filled area of the outline data shown in black in FIG. Hereinafter, as described above, a mesh that divides a character to set a flag for each block corresponding to a filled area of outline data is referred to as a flag mesh.

Next, as shown in FIG. 28, the flag meshes divided into 24 × 24 are collectively divided into 2 × 2 meshes (4 blocks). Hereinafter, the mesh for redistributing the flag mesh to generate the gray font in this way is referred to as a gray font mesh.

Then, of the 2 × 2 meshes (4 blocks) constituting one unit of this gray font mesh, how many meshes are flagged in the original 24 × 24 mesh bitmap font is counted. , 12 meshes for gray font according to the numerical value
It is displayed with gray values of four gradations showing the shade of gray corresponding to one block divided by a × 12 mesh.

That is, in the conventional embodiment, when 4 blocks out of 4 blocks are flagged, black is set to 4
Dark gray if 3 of the blocks are flagged, gray if 2 blocks are flagged, light gray if only 1 block is flagged, corresponding to 12 One block out of 144 blocks divided by × 12 mesh is displayed. If no flag is set for one block, the corresponding block is displayed in white as it is.

By doing so, as shown in FIG. 29, as a result, a 12 × 12 mesh gray font corresponding to ¼ of the size of the character represented in the original 24 × 24 mesh is generated. can do.

As described above, this conventional example has been described on the assumption that there is a one-to-one relationship between one block of the flag mesh and dots. However, one block and dots of the flag mesh are described. Does not have to be a one-to-one relationship with, for example, if a character of 48 × 48 dots is developed into a 24 × 24 flag mesh, one block of the flag mesh is composed of 2 × 2 dots (4 dots). Therefore, for example, if the mesh for gray font of 2 × 2 mesh is further divided as in this conventional example, one block of the mesh for gray font is displayed in gray with a white or four gradations in units of 16 dots. Will be.

[0016]

However, according to the above-described method of generating a gray font, the number of gray gradations is influenced by the size of the gray font mesh. For example, in the case of this conventional example, since the size of the gray font mesh is 2 × 2 mesh, it is limited to 4 gradations.

When the characters displayed in the same 12 × 12 binary bitmap font and the characters displayed in the gray font are compared, the characters displayed in the gray font are certainly more visible. However, as mentioned above, when capturing a large unit such as one block of a gray font mesh in 16-dot units as described above, the outer shape of the character becomes considerably difficult to determine. .

Further, as described above, n × is set in a state where a flag is set in units of one dot corresponding to the outline data.
A block is created by dividing the block by n meshes, the number of the flags in the block is counted, and each block has a shade dot having one shade of shades of multiple gradations according to the number of flags. Convert each to a signal and convert characters to n × n
There is also a method of generating a gray font by converting it into light and shade character data composed of individual light and shade dot signals. In this method, it is possible to have a multi-gradation gray color, which improves the visibility of the characters.
As in the above-described conventional method, the gray tone is still determined depending on the number of flags in one block, that is, the number of dots.

The present invention has been made in view of the above-mentioned points, and a gray font from outline data capable of displaying a complicatedly composed character and faithfully to the shape of the character regardless of size is beautiful. It is an object of the present invention to provide a generation method and an apparatus thereof.

[0020]

In order to achieve the above object, a gray font generation method from outline data according to claim 1 of the present invention is a method for generating outline data of n × n.
The area ratio of the area of the closed loop region of the data, which is formed by the intersection of the outline data and the square frame, is divided into n ² square frames by the mesh of (n is an integer). Is obtained, and the gradation value of the gray font of each square frame set by this area ratio is determined.

According to another aspect of the present invention, there is provided a gray font generation device for outline data, wherein a character input unit for inputting a character, an outline data storage unit for storing character information input by the character input unit as outline data, and n.
A division processing unit that divides the outline data by n ² square frames formed by a mesh of × n (n is an integer), and a closed loop region of the data by connecting intersections of the outline data and each square frame. A closed-loop region creating unit that creates a closed-loop region, an area-ratio calculating unit that obtains a ratio of the area in each closed-loop region to the area in each square frame, and a gray-scale value storage that stores a gray-scale value corresponding to the area ratio Unit, a conversion processing unit for converting the outline data into a gray gradation signal according to the gradation value, and a gray font composed of n × n gray gradation signals of the character output from the conversion processing unit. It is characterized by comprising a gray font data storage unit for storing data.

A gray font generation device for outline data according to a third aspect is the gray font generation device for outline data according to the second aspect, wherein the closed-loop area generation unit is arranged on the outer edge of the outline data. A section dividing unit that extracts points to be divided for each line segment section, a rectangular area creating section that creates a rectangular area that includes each of the line segment sections and has the section dividing points in a diagonal direction, and an X axis, Y for the rectangular area. A component-based data management unit that stores the data in which the components are rearranged for each axial direction, and a relation based on the data stored in the component-based data management unit for each square frame divided by the mesh in the division processing unit And a function extracting section for extracting a function corresponding to the rectangular area, and a related rectangular area extracting section for extracting the rectangular area. It is characterized by creating a closed-loop region by connecting the intersection between each square frame with the more extracted function.

According to the above-described method and apparatus for generating a gray font from outline data, the gradation value of the gray font for each square frame does not depend on the number of dots forming one character, and the area of the filled area is large. Since it is determined by the area ratio of the square frame and the area of each square frame, it is possible to obtain fine data, and therefore, the gray font gradation is also set to multiple gradations, and the characters divided into n × n according to this gradation. Each square frame of can be displayed.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a method for producing a gray font from outline data and an apparatus thereof according to the present invention will be described below with reference to FIGS.

FIG. 1 shows an embodiment of a gray font generating apparatus according to the present invention. This gray font generation device includes a character input unit 1 for inputting a character, an outline data storage unit 2 for storing the character information input by the character input unit 1 as outline data, and n × n (n
A division processing unit 3 that divides the outline data by n ² square frames formed by (n is an integer) mesh, and a square frame (hereinafter referred to as a block) that is divided by the outline data and the division processing unit 3 Closed-loop region creating unit 9 for creating a closed-loop region of the data by connecting the intersection points of
An area ratio calculation unit 10 for obtaining an area ratio in the closed loop region to an area in each block, a gradation value storage unit 11 for storing gradation values of light and shade corresponding to the area ratio, and the outline data for the outline data. A conversion processing unit 12 for converting into a gray gradation signal according to a gradation value, and a gray font for storing gray font data composed of m × m gray gradation signals of the character output from the conversion processing unit 12. It comprises a data storage unit 13.

Further, the closed loop creating section 9 has a section dividing section 4 for extracting points to be divided for each line segment at the outer edge of the outline data, and the section dividing points including the respective line segment sections are diagonal. A rectangular area creating unit 5 for creating a rectangular area and a component-based data storage unit 6 for storing data in which the rectangular area is rearranged in the X-axis and Y-axis directions by component.
A related rectangular area extracting section 7 for extracting the related rectangular area based on the data stored in the component-based data storage section 6 for each block, and a function extracting section for extracting a function corresponding to the rectangular area. 8 and is configured to connect a cross point of the function extracted by the function extracting unit and a block of the mesh forming the one block to create a closed loop region.

2 to 17 show an embodiment of a method for generating a gray font from outline data according to the present invention. In the present embodiment, the “technique” is the same as in the conventional example described above.
A case of displaying the Kanji in a gray font will be described.

First, by inputting with the character input unit 1 such as a scanner or a keyboard, outline data of a Chinese character "skill" is created and stored in the outline data storage unit 2 as shown in FIG. 2 (step ST1). ).

The division processing unit 3 divides the outline data of the Chinese character "skill" stored in the outline data storage unit 2 into a desired mesh size for reproduction (step ST2). The size of the character is determined by the size of the mesh to be reproduced. In this embodiment, as shown in FIG. 3, a 12 × 12 mesh (14
4 blocks).

Then, for each block, the ratio of the area of the one block to the area of the filled area of outline data (hereinafter referred to as the closed loop area) is obtained (step ST3).

Here, the creation of the closed loop area for each block will be specifically described with reference to FIG.

First, as shown in FIG. 5, the section dividing unit 4 extracts the section dividing points of the line segments that form the outline data (step ST11). As the section dividing points, the connecting points (bending points) of the straight lines of the line segments forming the outline data, the end points of the curved portions, and the like are extracted.

Then, as shown in FIG. 6, the rectangular area creating section 5 arranges the rectangular areas so that the area dividing points are diagonally arranged and includes the area segment having the area dividing points at both ends. create. FIG. 7A shows only the rectangular area thus created (step ST12).

Next, FIG. 7B shows the rectangular area created by the rectangular area creating section 5 in the component-specific data management section 5.
Then, as shown in FIG. 7 (c), the X components and the Y components are rearranged in ascending order and this data is stored (step ST
13).

8 to 18 show a process of displaying one block in the fifth column from the bottom to the fourth row from the bottom (hereinafter, referred to as a specific block) in gray shade in FIG. ,explain.

First, the related rectangular area extraction unit 7 extracts only the data related to the specific block from the X component / Y component data stored in the component data management unit 5 to extract the specific block. A rectangular area is reproduced (step ST14).

Here, the "related data" means the X component / Y component data shown on the horizontal and vertical axes in FIG.
As shown in FIG. 9, it is data (shown on the horizontal axis) of a rectangular area having at least one of the section division points within the X-axis coordinate range of the fixed block, and within the Y-axis coordinate range of the fixed block. It is data (shown on the vertical axis) of a rectangular area having at least one of the section dividing points. Then, the rectangular area extracted for both the X component and the Y component extracted as described above, that is, the rectangular area satisfying both the X component and the Y component, displays the inside of the specific block. It becomes a rectangular area including line segments.

Then, this rectangular area indicates a rectangular area indicated by a thick line in FIG. 10. By extracting the function corresponding to this rectangular area by the function extracting unit 8, the data of the line segment indicated by the thick line in FIG. 11 is extracted. Can be obtained (step S
T15).

Next, in the closed loop area creating unit 9, as shown in FIG. 12, the intersection points of the square frame of the mesh forming the specific block and the outline data developed in the specific block are connected to each other to form the closed loop area. Is created (step ST16).

Then, the area ratio calculation unit 10 calculates the ratio of the area in the closed loop region to the area of the specific block. One example of how to calculate this area ratio is shown in FIGS. Explained.

First, the number of divisions in the X-axis direction (or Y-axis direction) is determined according to the size of the specific block, and as shown in FIG. 14, the specific block is divided at equal intervals (see FIG. Step ST21 in 13). In this embodiment, it is divided into 12 in the X-axis direction.

Next, the straight lines used for the division (including the straight lines forming the frame of each block; hereinafter referred to as the division straight lines) and the function extracted by the function extracting unit 8, that is, the line segment of the specific block. The intersection is obtained, and it is determined whether or not it is within the closed loop region based on the direction of the tangent vector at the intersection (step ST22). Note that the direction of the function included in this specific block has already been specified at the time of extraction.
In the case of 5, the right side of the tangent vector is determined to be within the closed loop region.

Then, as shown in FIG. 16, the lengths of the straight line (thick line portion) in the closed loop region and the straight line (thin line portion) of the white region are obtained (step ST23).

A ratio of the total length of the divided straight lines to the total length of the straight lines in the closed loop region is calculated (step ST24). The ratio of the total length of the divided straight lines to the total length of the straight lines in the closed loop region has the same value as the ratio of the area of the block to the closed loop region area in the block (step ST25).

In this way, the area ratio can be obtained. It is needless to say that the method of obtaining the area ratio is an example, and can be calculated by other calculation methods.

Then, the area ratio calculated by the area ratio calculation unit 10 is associated with the numerical values of the gray gradation signal conversion table stored in the gradation value storage unit 11 to determine the gray gradation of each block. (Step ST4 in FIG. 2). For example, when the area of each block is 100 and the area of the closed loop region is 60, it is collated with the gray gradation signal conversion table as shown in Table 1 stored in the gradation value storage unit. Try to determine the gradation. in this case,
The gradation value is 10.

Then, the conversion processing unit 12 converts the outline data into a gray gradation signal according to the gradation value (step ST5).

Next, the gray font data composed of n.times.n gray gradation signals of the character output from the conversion processing unit 12 is stored in the gray font data storage unit 13 (step ST6), and FIG. As shown, the gray font data is displayed on a display such as a CRT (step ST7). That is, if the gradation value of the specific block having the closed loop region (illustrated by being filled in the drawing) as shown in FIG. 18 is 10, the gradation is displayed as shown in FIG.

As described above, according to the gray font generating method from outline data and its apparatus of the present embodiment, the area of one block divided by the mesh and the area of the closed loop region expanded in the block are The gray gradation can be determined from the ratio, and moreover, since the gradation number does not depend on the number of dots forming the block, it is possible to have many gradations. It becomes possible to display realistically according to the key.

The present invention is not limited to the above-mentioned embodiment, but can be variously modified as necessary.

The setting of the number of gradations described above is completely free,
For example, as shown in Table 1, 16 from white display to black display
The gradation may be set, or 5 gradations may be set as shown in Table 2. Further, the gray gradation can be displayed not only in grayscale display in black and white but also in color gradation.

[0052]

[0053]

As described above, according to the method and apparatus for generating a gray font from outline data according to the present invention, the area within a block divided by n × n mesh is expanded in each block. The gray gradation can be determined from the ratio with the area of the closed loop region, and since the gradation number does not depend on the number of dots forming the block, it is possible to have many gradations. The whole character can be displayed realistically with many gray gradations, and even with the complicated display of Kanji characters with a large number of strokes, the display will be an analog image display that is close to the exact character for human eyes. The effect is that even if the display is of any size, it can be displayed so beautifully as to distinguish the character shape.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an embodiment of a gray font generation apparatus according to the present invention.

FIG. 2 is a flowchart showing an embodiment of a method of generating a gray font according to the present invention.

FIG. 3 is a diagram in which outline data is divided into 12 × 12 meshes.

FIG. 4 is a flow chart illustrating an embodiment of creating a closed loop region.

FIG. 5 is a diagram in which segment division points are extracted.

FIG. 6 is a diagram showing a rectangular area including each section line segment.

7A is a diagram showing only the rectangular region of FIG. 4, FIG. 7B is a diagram in which the rectangular region is rearranged in ascending order by the X component, and FIG. 7C is a diagram in which the rectangular region is rearranged in ascending order by the Y component.

FIG. 8 is a basic diagram for extracting X and Y components of a related rectangular area.

FIG. 9 is a diagram in which XY components of a related rectangular area are extracted.

FIG. 10 is a diagram showing a result of extracting a rectangular area satisfying both conditions of X and Y components.

FIG. 11 is a diagram showing a result of extracting a function corresponding to the rectangular area.

FIG. 12 is a diagram showing the result of dividing and extracting the intersection of a square frame and each function.

FIG. 13 is a flowchart showing an embodiment for obtaining a ratio of an area in a closed loop region to an area of a specific block.

FIG. 14 is a diagram obtained by dividing a block into 12 in the X-axis direction.

FIG. 15 is a diagram in which an intersection between a dividing straight line and a function is obtained, and a closed loop region is specified at the intersection.

FIG. 16 is a diagram in which the lengths of a dividing straight line in the closed loop region and a dividing straight line in a portion other than the closed loop region are specified.

FIG. 17 is a diagram in which a specific block is displayed with gradation values of this block.

FIG. 18 is an explanatory diagram in which the closed loop area of the specific block shown in FIG. 17 is filled and displayed.

[Fig. 19] Character "skill" in outline data

FIG. 20 is a diagram in which outline data is divided by 12 × 12 mesh.

FIG. 21 is a diagram in which a filled area corresponding to outline data is specified.

FIG. 22 is a diagram in which a filled area corresponding to outline data is specified.

FIG. 23: Binary bitmap font of 12 × 12 mesh

FIG. 24 is a diagram showing a difference in visibility between the case where the character “skill” is represented by the binary bitmap font of the outline data and the grayscale of four gradations.

FIG. 25: The character “skill” in the outline data

FIG. 26 is a diagram in which outline data is divided into 24 × 24 meshes.

FIG. 27 is a diagram showing a filled area of the outline data.

FIG. 28 is a diagram in which the flag mesh divided into 24 × 24 is further divided into 2 × 2 (4 blocks) gray font mesh.

FIG. 29 is a diagram showing a generated 12 × 12 mesh gray font.

[Explanation of symbols]

 1 character input section 2 outline data storage section 3 division processing section 4 interval division section 5 rectangular area creation section 6 data storage by component 7 related rectangular area extraction section 8 function extraction section 9 closed loop area creation section 10 area ratio calculation section 11th floor Key value storage unit 12 Conversion processing unit 13 Gray font data storage unit

Claims (3)

[Claims] 1. Outline data is divided into n ² square frames by a mesh of n × n (n is an integer), and is formed by intersections of the outline data and the square frames with respect to an area in each square frame. A method for generating a gray font from outline data, characterized in that the area ratio of the areas of the closed loop region is calculated, and the gray font gradation value of each square frame set by this area ratio is determined. 2. A character input section for inputting a character, an outline data storage section for storing the character information input by the character input section as outline data, and n formed by an n × n (n is an integer) mesh. a dividing processing unit for dividing the outline data of ^two square frames, and closed region creating section that creates a closed-loop region of the data by connecting the intersection between each square frame with the outline data,
An area ratio calculation unit that obtains an area ratio in each closed loop region with respect to the area in each square frame, a gradation value storage unit that stores a gradation value of light and shade corresponding to the area ratio, and the outline data to the gradation. A conversion processing unit for converting into a gray gradation signal according to the value, and n × of the character output from the conversion processing unit.
An apparatus for generating a gray font from outline data, comprising: a gray font data storage unit that stores gray font data composed of n gray tone signals. 3. The closed-loop region creating unit extracts a point to be divided for each line segment of the outer edge of the outline data, and a rectangle having the segment division points diagonally including each line segment. A rectangular area creation unit that creates an area,
A component-specific data management unit that stores data in which the components are rearranged in the X-axis and Y-axis directions for the rectangular area,
A related rectangular area extraction unit that extracts the related rectangular area based on the data stored in the component-specific data management unit for each square frame divided by the mesh in the division processing unit, and the related rectangular region. The outline data according to claim 2, further comprising a function extracting unit that extracts a function, and creates a closed loop region by connecting an intersection of the function extracted by the function extracting unit and each of the square frames. Gray font generator from.