JPS5950070B2 - Character pattern generation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for generating a dot-type character pattern used in a dot-type character display device.

Conventionally, character generation methods when forming images by CRT or laser beam scanning include a matrix method, a stroke method, and a dot method.

The matrix method produces characters of good quality, but has drawbacks such as slow character generation speed and limited selection of character types.
The stroke method and dot method have fast character generation speeds, and both are used as character generation methods in current character generators, but they are not suitable for application to high-speed non-impact printers, external character processing, and conversion of font and size. The dot method is superior in terms of flexibility. In such a dot system, characters are arranged in, for example, 32 rows and 32 columns (32 x
32) into dot matrices, each character is stored in a semiconductor memory in the form of a dot matrix, but the storage capacity required for each character is
(32 x 32) ÷ 8 = 128 (bytes/character) is required, and if you want to store, for example, 4000 characters, (1
28 x 4000) ÷ 1000■ A large capacity memory of 512 bytes is required, and the currently available 16-bit EPROM (Erasable Programma)
Even if bleReadOnlyMemory) is used, 256 memory cells are required, making the memory device expensive.

Therefore, an important problem is how to store a large number of characters at a low cost.In order to save memory, characters are stored in a small number of dot patterns, and the number of dots is reduced during actual printing. When printing a large number of characters, a method is used in which the original character pattern stored in a small number of dots is enlarged and output. By doing so, it becomes possible to generate a character pattern of any size for the same character by simply storing one type of character pattern with the lowest capacity. As a method of enlarging such a character pattern, as described in Japanese Patent Application Laid-Open No. 51-92125, the logical sum of appropriately selected adjacent rows or columns of black dots is calculated, and the above-mentioned method is performed. There is a method to insert new rows or columns formed by logical sum between adjacent rows or columns.
Character patterns formed by this method have the disadvantage that the line thickness of the characters is not uniform, resulting in unbalanced character patterns.

Furthermore, as described in Japanese Patent Application Laid-Open No. 52-68326, there is a method of focusing only on black dots and enlarging the characters proportionally;
When the standard pattern represented by the black dots in the dot matrix shown in Figure 2 is expanded to a 32x32 dot matrix by 4/3 times both vertically and horizontally, black dots appear in the character pattern as shown in Figure 2. The quality of the characters deteriorates as the missing parts become visible. Also, the height and width are doubled, 48×
When enlarged to 48 dot matrices, the positions of the black dots became checkered, as shown in FIG. 3, resulting in an extremely poor character quality. The fundamental drawback of this method is that even if one black dot in the standard pattern is enlarged, it only increases to two black dots, so if the magnification is 3 times or more, the black dots will be completely ignored. It becomes continuous and cannot be read as a character pattern. It is an object of the present invention to provide a method for generating dot-shaped character patterns that does not have the above-mentioned drawbacks.

That is, an object of the present invention is to provide a method for generating dot-shaped character patterns that generates large characters with a large number of dots with a small memory capacity, and also to provide a method for generating dot-type character patterns that produce enlarged characters of good quality. It is to provide. In particular, it is an object of the present invention to provide a method for generating a dot-shaped character pattern that maintains a uniform thickness even if the vertical or horizontal line segments are expanded. The present invention is a system in which a standard character pattern is stored in a dot matrix by the coordinate values of black dots, and a character pattern is generated by approximately enlarging the standard character pattern.
Convert the coordinate values of the black dots in the standard character pattern into new coordinate value groups in both the vertical and horizontal directions independently using the following formula, and generate a matrix consisting of the coordinate value groups in both directions as black dots. This is a character pattern generation method characterized by the following.

However, [ ] is a Gauss symbol, I is the coordinate value of the black dot in the standard character pattern, i is the coordinate value of the black dot in the enlarged character pattern, α is the enlargement magnification, m is an integer, and m-1〈α
≦m. k is a constant and O≦k≦1.

Next, the system of the present invention will be explained with reference to the drawings.

FIG. 4 is a block diagram for explaining the signal flow of the character pattern generation system of the present invention. In the drawings, 1 is an input device such as a magnetic tape, and 2 is a central processing unit. A decoder 3 decodes the character code sent from the central processing unit 2 and sends the signal to the font memory 4 in which character patterns are stored in a standard dot matrix.

Font memory 4 sends the character pattern corresponding to the input signal to buffer memory 5. Reference numeral 6 denotes a register into which one horizontal row or one vertical row of the single character pattern input into the buffer memory 5 is input.

On the other hand, the decoder 3 sends the character size parameter sent together with the character code from the central processing unit 2 to the character size register 10. Reference numeral 7 is an arithmetic circuit which is a feature of the method of the present invention, and inputs the coordinate value of a black dot in a horizontal or vertical line of characters represented by a dot pattern input from register 6 from character size register 10. It multiplies the input character size parameters, performs integer conversion and other operations as described later, and outputs the results.

Reference numeral 8 denotes a buffer memory for storing the calculation results from the calculation circuit 7, and initially contains white dots.

In this way, buffer memory 8 has font memory 4.
An enlarged pattern of the character pattern stored in is stored, and this enlarged character pattern is sent to an output device 9 such as a printer. Next, the calculations performed in the calculation circuit 8 will be further explained.

Assuming that the standard character pattern stored in the font memory 4 is formed in an MXN dot matrix, and the enlarged character is formed in an M″×N″ dot matrix, the vertical The enlargement magnification, that is, the vertical character size parameter α, is α=M″/M, and the horizontal enlargement ratio, that is, the horizontal character size parameter β.
becomes β=N7N. Let the coordinates of an arbitrary black dot in the standard character pattern be I, J, and the coordinates of that black dot in the enlarged character pattern be I, j. In this way, the new coordinates I, j become a group of coordinates that increases as the magnification increases. These coordinate groups are all combinations of those indicated by adding subscripts to I and j, respectively. The coordinate groups I and j of the black dot after enlargement are respectively expressed by the following equations. The vertical coordinate i after enlargement is a set of the following coordinates. (2
) However, q = 2, 3, ..., n. [ ] is a Gaussian symbol.

m and n are the smallest integers that are equal to or larger than the vertical and horizontal magnification magnification, respectively, and m-1<
It is expressed by α≦m, n-1<β≦n. Also k and 1
When converting the value obtained by multiplying the coordinate value of the black dot in the standard character pattern by the magnification magnification into an integer, the value is rounded off to the nearest whole number, rounded up or down, etc.
It may be arbitrarily selected within the range of o≦k and l≦1. For example, when rounding off people both vertically and horizontally, k
=l=0.5. The above formula (l) and formula (2
), one black dot in the standard character pattern expands to a maximum of Mxn black dots in the enlarged character pattern.

In formula (1) and formula (2), there are m and n calculation formulas, respectively, but since Gauss symbols are used, some calculation results will be the same value, so the actual number of black dots is Mxn at most. This situation is shown in FIG. Figure 5 shows the coordinates I and J in the standard character pattern.
This figure shows how a black dot at coordinates I and j spreads to a black dot at coordinates I and j in an enlarged character pattern. k=1=0 in the drawing
．． It is listed as 5. That is, i is I,,i. ，・・・・・・
・It is a set of Im, and j is J,,j. ，・・・・・・・・・
It becomes a set of Jn. The size of the integers m and n is determined by the size of the magnification factors α and β, so for example, 2<α, β≦
3, the black dot matrix in FIG. 5 becomes 3×3. Next, a specific example will be explained with reference to FIG. 6 and Table 1. Figure 6a shows a line segment consisting of black dots in a standard character pattern, and Figure 6b shows a line segment made up of black dots in a standard character pattern.
Line segment of Fig. 6 a enlarged to α = β = 4/3, Fig. 6 c
6A and 6B respectively illustrate the line segments of FIG. 6a enlarged to α=β=4/3 by the method of the present invention. Table 1 also shows the coordinate values of the black dot in the standard character pattern in Figure 6a,
From those coordinate values, formula (l) and formula (2) (where k
The coordinate values of black dots in the enlarged character pattern calculated using (=l=0.5) are shown. In the conventional method, I,,j in Table 1.

and I. , j, and as shown in Figure 6b, the line segments are not continuous with uniform thickness, making it difficult to read the enlarged character pattern as characters, as mentioned above. According to the inventive method, as shown in FIG. 6c, the line segments are continuous with uniform thickness, so that the enlarged character pattern can be immediately read as characters. In Figure 6, the line segments made of black dots are long horizontally, but even if the line segments made of black dots are long vertically, the thickness of the line segments in the enlarged character pattern becomes uniform by the formula ( 1) and equation (2)
It is clear that they are essentially the same thing. Considering that characters have a large number of vertical and horizontal line segments, one can judge how effective the method of the present invention is in practice. Furthermore, examples of character patterns obtained by enlarging the standard character pattern of FIG. 1 using the method of the present invention are shown in FIGS. 7 to 9. Figure 7 shows an example expanded to a 32 x 32 dot tomato turret.
If you compare it with the figure, and if you compare it with Figure 3, where Figure 8 is an example enlarged to a 48 x 48'' dot matrix, you can clearly see the effect of the method of the present invention.Furthermore, Figure 9 shows This is an example where the magnification ratios in the vertical and horizontal directions are different, and the image is expanded to a 32x28 dot matrix.The method of the present invention is very effective even when the magnification ratios in the vertical and horizontal directions are different like this. Therefore, the continuity of the line segments of the enlarged pattern is maintained.As explained above, according to the present invention, even if the dot-shaped character pattern is enlarged at an arbitrary magnification, the character quality does not deteriorate. is obtained.

According to the present invention, an enlarged character pattern that does not deteriorate in character quality even when the enlargement factor is large can be obtained. According to the present invention, an enlarged character pattern with good character quality can be obtained, especially since the vertical and horizontal line segments have a uniform thickness. Furthermore, according to the present invention, if only one type of dot matrix is stored in the relatively small number of dot matrices for each character, characters with different vertical and horizontal magnifications and characters of any size can be generated. The memory can have a small capacity, thus making the character generator inexpensive and compact.

[Brief explanation of drawings]

Figure 1 is an example of a standard pattern expressed in a 24x24 dot matrix.

Claims (1)

[Claims] 1. A method in which a standard character pattern is stored in a dot matrix by coordinate values of black dots, and a character pattern is generated by approximately enlarging the standard character pattern. It is characterized by converting the coordinate values of black dots in the pattern into new coordinate value groups in both the vertical and horizontal directions independently using the following formula, and generating a matrix consisting of the coordinate value groups in both directions as black dots. Character pattern generation method. i_1=[α I +k] i_p=[α( I +1)+k]-(m-p+1)P=
2, 3, ..., m, where [ ] is a Gauss symbol, I is the coordinate value of the black dot in the standard character pattern, i is the coordinate value of the black dot in the enlarged character pattern, α is the enlargement magnification, and m is an integer and m-1<α≦m, k is a constant and 0≦k≦1.