JP2618528B2 - Character drawing device, character output correction method, and character output device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device such as a laser beam printer or a display device, and more particularly to a device suitable for outputting high-quality characters using an outline font. For character devices.

[Conventional technology]

There is an outline font as a storage format of character data in a display device such as a laser beam printer and a display. An outline font stores the shape of a character as a coordinate sequence of the outline of the character. In order to print this outline font, first, coordinate conversion is performed on each outline coordinate value in order to obtain a desired print size, and then processing is performed in which the inside of the converted outline coordinates is painted out. Outline fonts have the advantage that they can be freely scaled, rotated, deformed, etc., but when printing small characters of 64 x 64 dots or less, the line widths of vertical and horizontal lines of characters are not uniform due to quantization errors. And there is a problem that the display quality of characters is deteriorated.

As a conventional method for correcting the line width, the line widths of the vertical line and the horizontal line are stored in a table in advance, and when printing, one of the two contour lines forming the vertical line and the horizontal line is used. There is a method of referring to the line width stored in the table with reference to the reference line, determining the other contour line coordinates, correcting the line width, and realizing high quality printing.

Incidentally, Japanese Patent Application Laid-Open No. 2-8165
There is No. 7.

[Problems to be solved by the invention]

However, in the above conventional method, it is necessary to store line width information in a table for each character size. For this reason, there is a problem that the printable character size is limited by the presence or absence of the line width information. Further, in the above-described conventional method, it is possible to correct the line widths of the horizontal and vertical lines, but no consideration is given to the correction of a white region surrounded by two horizontal lines or two vertical lines.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a character drawing device and the like which can correct a line width for an arbitrary character size even for an outline font having no additional information for line width correction.

Another object of the present invention is to provide a high-quality character drawing apparatus and the like that takes into account not only correction of the line width of horizontal and vertical lines, but also correction of a white area surrounded by two horizontal lines or two vertical lines. Is to provide.

[Means for solving the problem]

The above object is to extract the outline coordinates of the horizontal and vertical lines from the outline coordinates after the coordinate conversion, convert the intervals between the outline coordinates into integers, and recalculate the outline coordinates based on the obtained integer intervals. Is achieved.

When the interval between the contour coordinates is converted to an integer, the overall length expands and contracts, but one of the black region and the white region is fixed with a uniform width, and the other is corrected with emphasis on symmetry. This is achieved by correcting the overall length.

[Action]

The integer interval calculating unit automatically extracts the outline coordinate values of the horizontal and vertical lines from the character outline coordinate data, and individually converts each interval to an integer. As a result, it is possible to prepare line width correction information for an arbitrary character size in advance.
The interval between the contour coordinates that was the same before the conversion to the integer is the same after the conversion to the integer.

In addition, since the overall length correction unit performs correction with emphasis on symmetry at the time of correction, it is possible to perform high-quality correction while maintaining symmetry.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a configuration diagram of a character drawing apparatus according to an embodiment of the present invention. When the host computer 1 transfers the print command to the character drawing device 2, the character drawing device 2 receives the print command, generates a character image, and transfers the character image to the display device 3. The display device 3 is a laser beam printer, a graphic display, or a liquid crystal display device.
Print or display the character image.

Inside the character drawing device 2, the data reading unit 20 decodes the typeface information and the character code sent from the host computer 1, and reads out the specified character outline coordinate data from the font storage unit 20 to the work memory 25. . Coordinate converter 22
Receives character size information from the host computer 1 and converts the character contour coordinate data read into the work memory 25 to a predetermined size. At this time, if the character outline coordinate data includes a curved expression such as a Bezier curve, a spline curve, or an arc, the coordinate conversion unit 22 performs a linear approximation process. The converted character outline coordinate data is corrected by the line width correction unit 23. The filling unit 24 generates a character image by filling the inside of the outline based on the corrected character outline coordinate data, and
Transfer to

Inside the line width correction unit 23, first, the closed figure separation unit 230
The character outline coordinate data converted by the coordinate conversion unit 22 is separated into groups of coordinate data strings forming a closed figure, cut out one by one, and the range is specified to the integer interval extraction unit 231. The following processing of the line width correction unit 23 is sequentially performed on each group divided by the closed figure separation unit 230.

FIG. 2 shows the operation of the integer interval extracting unit 231. In FIG. 2, the operation will be described by taking as an example the processing on the y-coordinate of the horizontal line contour coordinates of the character "date". In the following, only the processing on the y-coordinate of the horizontal line contour coordinates will be described with reference to FIG. 2, but the same processing is performed on the x-coordinate of the vertical line contour coordinates.

The y coordinate (y0 to y6) of the horizontal line outline coordinate is extracted from the coordinate data group designated by the closed figure separation unit 230, and the maximum y coordinate of the coordinate data group is set to the y coordinate of the horizontal line outline coordinate. Add a value / minimum value, sort, remove duplicated coordinate values,
Remember to 1000.

Next, differences (dy0 to dy5) between adjacent coordinate values of the horizontal line table 1000 are calculated, and the horizontal line interval table 1001 is calculated.
To memorize. Further, each element of the horizontal line interval table 1001 is converted into an integer, and the result (idy0 to idy5) is stored in the integer horizontal line interval table 1002.

In addition, the total (yt) of the elements of the horizontal line interval table 1001 is obtained and stored in the overall length table 1003, and the entire integer (iyt) obtained by converting the overall length (yt) into an integer is stored in the entire integer length table 100.
Remember in 5. Further, the sum (iy) of the integer horizontal line intervals (idy0 to idy5) stored in the integer horizontal line interval table 1002
s) is obtained and stored in the integer horizontal line interval total table 1004.

Next, a plurality of total horizontal line intervals (iys) stored in the integer horizontal line interval total table 1004 and an integer overall length table 1004
The difference (dyt) from the whole integer length (iyt) stored in 5 is obtained and stored in the entire length error table 1006. The overall length error (dyt) stored in the overall length error table 1006 is used by the overall length correction unit 232.

On the other hand, when extracting the y coordinate of the horizontal line contour coordinates,
It is checked whether each horizontal line outline coordinate corresponds to the upper side or the lower side of the line segment, and the result is stored in the horizontal line attribute table 1007. Next, the area surrounded by the upper side on the upper side and the lower side by the lower side is determined as a black area, and the rest is determined as a white area, and the result is stored in the area attribute table 1008. The information stored in the area attribute table 1008 is used by the overall length correction unit 232.

In the overall length correction unit 232, first, the overall length error table 1006
Check the total length error (dyt) stored in
If yt) is not 0, the correction process is performed. If 0, no process is performed, and the next coordinate point correction unit 232 is started.

When the overall length error (dyt) is not 0, the overall length correction unit 232 corrects the overall length by the following processing shown in FIG. First, in step 2000, the area attribute table 10
In 08, the contents of the changeable table 1009 are initially set to unchangeable and changeable, corresponding to the attributes of the black area and the white area. Next, in step 2001, among the elements of the integer horizontal line interval table 1002, the corresponding changeable table
List the area with the largest width among those whose contents of 1009 can be changed. This will be referred to as a change target area.

Here, the absolute value of the total length error (dyt) is defined as adyt, and dyt ÷
adyt. In step 2002, if the number of change target areas is smaller than or equal to adyt, sdyt is added to the width of all change target areas in step 2003, and step 20
In 04, if dyt is greater than 0, step 200
5, the changeable table 1 corresponding to the change target area
Make the contents of 009 unchangeable.

On the other hand, in step 2002, if the number of change target areas is larger than adyt, the entire length error is dispersed in the change target areas. At this time, in step 2006, the ad
If yt is an odd number, sdyt is added to the width of the change target area in order from the center area of the change target area in step 2007 and from both end areas in step 2008 if it is even.

After the above processing, in step 2009, the area to be changed is subtracted from adyt. If the result is that adyt is 0 or less, the entire length correction processing is terminated, and the next coordinate point correction unit 233 is started. If adyt is greater than 0, the process returns to step 2002.

FIGS. 4 and 5 show the transition of the pattern of the character graphic by the overall length correction unit 232. FIG. FIG. 4 shows a case where the area having the maximum width is smaller than adyt,
This shows that 2002, 2003, 2004, 2005, 2009, and 2010 are repeated three times. The width of the black area does not change at the width 1, and the width of the white area increases by one dot in order from the wide area. In FIG. 5, there are a plurality of areas having the maximum width, and the number of the areas is adyt
Indicates a case of greater than The diagram on the left shows a case where the correction amount adyt is an odd number. Steps 2002, 2006, and 2007 are executed, and the width is corrected in order from the central white region. On the other hand, the right figure shows the correction amount adyt
Is an even number, and steps 2002, 2006, and 2008 are executed, and the width is corrected in order from the white regions at both ends.

After the processing of the overall length correction unit 232 is completed as described above,
The coordinate point correction unit 233 corrects the character outline coordinate data. The coordinate point correction unit 233 first determines outline coordinate values of horizontal and vertical lines, and then corrects each coordinate point based on the outline coordinate values of the horizontal and vertical lines.

FIG. 6 shows how to determine the outline coordinate value of the horizontal line. By adding each element of the integer horizontal line interval table 1002, corrected horizontal line outline coordinates (ny0 to ny6) are generated and stored in the corrected horizontal line table 1010. That is, ny1 is calculated by adding the integer interval idy0 to the reference point coordinate ny0. ny
Add idy1 to 1 to find ny2. Similarly, nyi and idyi
Is repeated to obtain ny (i + 1).

After all the corrected horizontal lines (ny0 to ny6) are obtained, all the coordinate points are corrected. That is, the following processing is performed for each coordinate point. First, a coordinate value to be corrected is compared with an element of the horizontal line table 1000 to determine to which region the coordinate point belongs. Next, as shown in FIG. 7, the coordinate point y is represented by yi and y (y
+1), the corrected coordinate point ny is obtained by the following equation.

By the above embodiment, without deteriorating the symmetry of the character,
There is an effect that characters with uniform horizontal and vertical line widths can be printed or displayed.

Another embodiment will be described with reference to FIGS. 7 and 8. FIG. In this embodiment, the contents of the changeable table 1009 are stored in the area attribute table in step 2000 of FIG.
Initially, changeable and non-changeable are set in accordance with the attributes of the black area and white area in 1008, respectively.

FIGS. 7 and 8 show the transition of the pattern of the character graphic by the overall length correction unit 232. FIG. FIG. 7 shows a case where the region having the maximum width is smaller than adyt, and shows a state where the third step 2002, 2003, 2004, 2005, 2009, 2010 is repeated three times. The white area does not change at the width of 1, and the black area increases in width by one dot in order from the wide area. In FIG. 9, there are a plurality of areas having the maximum width, and the number of the areas is ad.
Indicates a case greater than yt. The left figure shows the case where the correction amount adyt is an odd number, and the steps are executed in steps 2002, 2006, and 2007, and the width is corrected in order from the central black area. On the other hand, the right figure shows the correction amount ad
This is the case where yt is an even number. Steps 2002, 2006, and 2008 are executed, and the width is corrected in order from the black regions at both ends.

By the above embodiment, without deteriorating the symmetry of the character,
There is an effect that characters with uniform horizontal and vertical line spacing can be printed or displayed.

〔The invention's effect〕

According to the present invention, even for an outline font having no additional information for line width correction, the line width can be corrected for an arbitrary character size. In addition, not only the line width of the horizontal and vertical lines can be corrected, but also a white region surrounded by two horizontal lines or two vertical lines can be corrected, and high-quality characters can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a character drawing apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of a processing method of an integer interval extraction unit, FIG.
FIG. 4 is a flowchart of a processing method of the overall length correcting unit, FIG. 4 is an explanatory diagram of a first processing result of the overall length correcting unit, FIG. 5 is an explanatory diagram of a second processing result of the overall length correcting unit, and FIG. FIG. 7 is an explanatory diagram of a first process of the coordinate point correcting unit, FIG. 7 is an explanatory diagram of a second process of the coordinate point correcting unit, FIG. 8 is an explanatory diagram of a first processing result of the overall length correcting unit in the second embodiment, FIG. 9 is an explanatory diagram of a second processing result of the overall length correction unit in the second embodiment. 1 host computer, 2 character drawing device, 3 display device, 20 font storage unit, 21 data reading unit,
22 ... Coordinate conversion unit, 23 ... Line width correction unit, 24 ... Filling unit, 230 ... Closed figure separation unit, 231 ... Integer interval extraction unit,
232: Overall length correction unit, 233: Coordinate point correction unit.

Claims (15)

(57) [Claims] 1. A character drawing device for forming an outline font, comprising: a closed figure separation unit for separating character outline coordinate data converted into a predetermined character size by coordinate conversion for each closed figure; The y-coordinate of the horizontal line outline coordinate and the x-coordinate of the vertical line outline coordinate are extracted from the obtained character outline coordinate data, the interval between the coordinate values corresponding to each of the coordinate values is determined, and the interval is converted into an integer. Integer interval calculator and sum of intervals converted into integers by the integer interval calculator, and when there is a difference between the total value and the entire length of a character, correct the total value and the entire length so that they match. A coordinate point correction unit that recalculates and corrects the y coordinate of the horizontal line outline coordinate and the x coordinate of the vertical line outline coordinate by adding the intervals corrected by the overall length correction unit, Line consisting of Character rendering device, characterized in that it comprises a correction unit. 2. The character drawing apparatus according to claim 1, wherein the overall length correction unit corrects the width by one dot in order from the widest white area. 3. The apparatus according to claim 2, wherein, when there are a plurality of white areas having the widest width, a central area is provided when the difference between the total value of the intervals and the overall length of the character is an odd number. A character drawing device that corrects the width by one dot in order from both end regions when the number is an even number. 4. The character drawing apparatus according to claim 1, wherein the overall length correction section corrects the width one dot at a time in order from the widest black area. 5. An apparatus according to claim 4, wherein, when a plurality of black areas having the widest width are present, the difference between the total value of the intervals and the overall length of the character is an odd number. A character drawing apparatus for correcting dots one by one in order from an area at both ends of an area. 6. A character drawing device according to claim 1, a host computer for sending a print command to said character drawing device, and an output device for displaying a character image generated by said character drawing device. A data processing device comprising: 7. An apparatus according to claim 6, wherein the output device is a laser.
Beam printer, graphic display terminal,
A data processing device characterized by being one of liquid crystal display terminals. 8. The character drawing apparatus according to claim 3, wherein the character outline coordinate data is such that two horizontal lines or vertical lines having the same line width have the same line width after printing. 9. The character outline coordinate data according to claim 5, wherein, in one closed figure, two white areas having the same width among white areas surrounded by two horizontal lines or vertical lines. A character drawing device characterized in that the same width is maintained after printing. 10. A y-coordinate value of each horizontal line contour coordinate constituting the character is calculated from character coordinate data of an outline font of a character to be output converted to an arbitrary size, and an interval between adjacent y-coordinate values is calculated. A character output correction method, characterized in that a difference between a value obtained by converting the total value of the intervals into an integer and a value obtained by summing the values obtained by converting the respective intervals into an integer is used as a vertical correction amount at the time of outputting the character. 11. An x-coordinate value of each vertical line contour coordinate constituting the character is calculated from character coordinate data of an outline font of an output target character converted to an arbitrary size, and an interval between adjacent x-coordinate values is calculated. A character output correction method, characterized in that a difference between a value obtained by converting the sum of each interval into an integer and a value obtained by summing the values obtained by converting each interval into an integer is used as a horizontal correction amount when the character is output. 12. A y-coordinate value of each horizontal line contour coordinate forming the character is calculated from character coordinate data of an outline font of the output target character converted to an arbitrary size, and an interval between adjacent y-coordinate values is calculated. The difference between the value obtained by converting the total value of the intervals into an integer and the value obtained by summing the values obtained by converting each of the intervals into an integer is calculated.
A character output correction method, wherein, among the above intervals, intervals indicating non-character areas are corrected in a direction in which the difference becomes smaller by one dot in ascending order of the intervals. 13. An x-coordinate value of each water perpendicular outline coordinate constituting the character is calculated from character coordinate data of an outline font of the output target character converted to an arbitrary size, and an interval between adjacent x-coordinate values is calculated. Find the difference between the value obtained by converting the total value of each interval to an integer and the value obtained by summing the values obtained by converting each interval to an integer,
A character output correction method, wherein, among the above intervals, intervals indicating non-character areas are corrected in a direction in which the difference becomes smaller by one dot in ascending order of the intervals. 14. A character output device for outputting characters in an outline font, comprising means for outputting characters corrected in the vertical and horizontal directions of the characters output by each of the methods of claim 12. A character output device characterized by the above-mentioned. 15. A character output device for outputting characters in an outline font, comprising means for executing the method according to claim 10 and calculating the vertical and horizontal correction amounts of the characters to be output. A character output device characterized by the above-mentioned.