JP2956705B2 - Data converter - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data conversion device for converting outline data representing outlines of figures including characters such as characters and symbols into dot data, and more particularly to a data conversion apparatus. The assurance of symmetry and smoothness.

2. Description of the Related Art When processing data representing figures such as characters and symbols using a computer and displaying the data in any form such as printing or display, it is widely used to form dot data for each pixel, which is the minimum processing unit. Is being done. At this time, if dot data is created in advance for the entire graphic to be displayed and stored in the memory, an extremely large memory is required, and as shown in JP-B-53-41017, the graphic is It is preferable that the data is stored as outline data representing the outline and converted into dot data by a device having dot data conversion means at the time of printing, display, or the like.

A pixel screen is used to convert outline data into dot data. The pixel screen defines pixels by a plurality of definition lines parallel to the X-axis and the Y-axis, which are orthogonal to each other in one plane, and the data conversion unit superimposes the outline of the graphic on the pixel screen. In such a case, the dot data corresponding to the pixel whose outline includes a portion equal to or more than a predetermined reference is set as data representing the presence of a figure, and the outline data is converted into dot data.

However, when the outline data is converted to dot data and a graphic is displayed in this manner, even if the graphic is the same depending on the position where the character is displayed, the number, position, etc. of pixels included in the outline at a certain level or more. And the shape may be different. In particular, if the graphic is a symmetric graphic having an axis of symmetry parallel to the X or Y axis of the pixel screen,
The outline should be designed so that the symmetrical part is displayed with the same shape and size, but if the number and position of the pixels included in the outline differ depending on the displayed position, the shape of the symmetrical part The sizes are different from each other and are not displayed symmetrically.

Some graphics have a convex curved portion that is smoothly convex in one of the positive and negative directions of the X-axis or one of the positive and negative directions of the Y-axis, such as the letter D in the alphabet. . Such a convex portion is defined by an arc-shaped contour, but depending on the display position of the figure, the maximum point that projects most in the positive direction or the minimum point that projects most in the negative direction of the convex portion of the contour line is determined. The included portion is displayed by one pixel in a direction perpendicular to the direction of the projection, and a projection may be formed at the protruding end of the protruding portion, so that a smoothly curved display may not be obtained.

Therefore, in the data converter disclosed in Japanese Patent Application Laid-Open No. 60-39280, the outline data of a figure is translated and expanded on a pixel screen, and the maximum value and the minimum value of the figure in the X-axis direction are reduced. And Y
The maximum value and the minimum value in the axial direction are respectively located in the middle of two adjacent pixel defining lines (lines connecting the pixel center points). In this data conversion apparatus, dot data corresponding to a pixel whose center point is included in the outline of the figure is set to data representing the presence of the figure, and the pixel center point is located on the outline. The same applies to pixels. In a contour defining a symmetrical portion of a figure having an axis of symmetry parallel to the X axis or the Y axis, there are maximum and minimum values of the X coordinate or Y coordinate of the figure, which are defined with respect to the pixel defining line. By positioning the pixels at the same relative position (intermediate position), the pixels displaying the symmetrical portion are positioned symmetrically with respect to the axis of symmetry and have the same number of pixels, and dot data for displaying the figure symmetrically is obtained. Can be Also, in the case of a figure having a convex curved portion, when the local maximum point and the local minimum point have the maximum value and the minimum value of the X coordinate or the Y coordinate, a projection is formed at the protruding end of the convex curved portion. However, if they are located in the middle between two adjacent pixel defining lines, the maximum point and the minimum point are defined as the positions farthest and nearest from the pixel center point immediately inside the contour line. Since it is located exactly at the center, the right number of pixel center points in the direction orthogonal to the convex direction will be included in the outline, and the tip of the convex curved portion will be displayed smoothly by an appropriate number of pixels. You. The position farthest from the pixel center point immediately inside the contour line is the position closest to the pixel center point, not including the pixel center point adjacent to the pixel center point in the convex direction, and the local maximum point at that position. If the minimum point is located, a large number of pixel center points are included in the contour in a direction orthogonal to the convex direction, and the contour may be displayed flat instead of convex. The position closest to the pixel center point immediately inside the contour line is a position on the pixel center point. If a maximum point or a minimum point is located at that position, the pixel center point included in the contour is determined. Number one
The projections are formed individually. Therefore, if the local maximum point and the local minimum point are located exactly at the center between the farthest position and the closest position from the pixel center point just inside the outline, the number of the pixel center points can be included in the outline without excess or deficiency. That is, the convex curved portion is displayed smoothly.

Also, in the data conversion apparatus described in Japanese Patent Application Laid-Open No. 61-51189, correction data indicating a method of correcting outline data when a graphic is reduced or enlarged is added to each graphic, and the data is added in accordance with the data. Reduction and enlargement are performed. The correction data is data that specifies a skeleton point that must be consistent with the specified line of the pixel screen because the skeleton of the figure is specified among a plurality of points that specify the figure, data that specifies the distance between these skeleton points, In the case of having an inclined portion, it is composed of a large number of data such as data defining the inclination angle, and the reduction and enlargement of the figure are always performed in almost the same shape regardless of their display position, According to this data converter, it is considered that symmetry and smoothness can be guaranteed.

Problems to be Solved by the Invention However, in the data conversion device described in Japanese Patent Application Laid-Open No. 60-39280, the parallel conversion, compression, and enlargement are performed uniformly for all figures, so that the data conversion takes time. was there. Further, in the case of the data conversion device described in Japanese Patent Application Laid-Open No. 61-51189, a large number of correction data are required for each figure, and there is a problem that the data amount increases and the processing takes time.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus capable of ensuring the symmetry of a figure and the smoothness of a convex portion as much as possible while rapidly converting outline data of a figure into dot data with a small data amount. It is a thing.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides, as shown in FIG. 1, a coordinate point data representing each coordinate value of a plurality of coordinate points and a type of a line connecting the two coordinate points. Is superimposed on a pixel screen that defines pixels by a plurality of definition lines parallel to the X-axis and the Y-axis, respectively, which are orthogonal to each other, represented by outline data including outline data including line element data. Data conversion means for converting outline data into dot data by setting dot data corresponding to pixels included in the outline in a state satisfying a certain standard, assuming that they match, by setting the dot data to data representing the presence of a figure. When the figure has a symmetry axis parallel to the X axis or the Y axis, axis designating data indicating an axis parallel to the symmetry axis; An instruction including convex direction instruction data for instructing the direction of the convex when a convex convex portion is smoothly convex in one of the positive and negative directions of the X-axis or the positive and negative directions of the Y-axis; Instruction data storage means for storing data in association with outline data of a graphic; and an axis designated by the axis instruction data, the coordinate values of all the coordinate point data of the outline data associated with the axis instruction data. Is translated equally in the direction perpendicular to the axis, so that the axis of symmetry of the figure is at one of the prescribed lines parallel to the axis of symmetry or at the middle of two prescribed lines parallel to and adjacent to the axis of symmetry. The coordinate values of all the coordinate point data of the outline data associated with the convex direction designating data are matched with the one straight line located, and the convex direction designating is performed. Data, the maximum point or the minimum point of the convex curved portion is located near the position where the maximum point or the minimum point of the convex curved portion is located. An outline data correcting means for setting dot data respectively corresponding to two or more pixels which are continuous with each other in a direction orthogonal to the direction specified by said convex direction designating data at a position set in data representing the presence of a figure; And data conversion means for converting the outline data corrected by the outline data correction means into dot data.

In order to guarantee the smoothness of the convexly curved portion, the above-mentioned JP
If the maximum point and the minimum point are located at the center of two pixel defining lines connecting the pixel center points as in the data converter of No. 60-39280, the convex curved portion is orthogonal to the convex direction. It will be displayed by an appropriate number of pixels in the direction, but this is not essential. If the maximum point and the minimum point are located outside the position where the convex curved portion is displayed by one pixel in one pixel, the display can be performed by two or more pixels, and the radius of curvature of the convex curved portion is obtained. Depending on the size of the pixel and the size of the pixel, the display may be smoothly performed by two pixels.

If the maximum point and the minimum point are located at positions other than the center of the two pixel defining lines connecting the pixel center points, the movement amount of the outline data can be reduced, and such positions must be determined in advance. Can be. For example, since the radii of curvature and the pixel sizes of all the convex curved portions of the displayed graphic are known when designing the graphic, the convex curved portion having the smallest radius of curvature of the convex curved portions is the smallest size. When displaying in (If there is only one type of display size, that size)
Based on the radius of curvature of, the position where the pixels included in the contour are out of the position where the number of pixels is one, and the number of pixels included in the outline is two or more and the position closest to the position where the number of pixels is one One point is obtained for each direction in the direction opposite to the direction of the protrusion, and the maximum point and the minimum point are located at the closest one of the two positions regardless of the display size and the type of the convex part at the time of display. The outline data is translated in such a manner that

Action and Effect If the symmetry axis of the figure is made coincident with one specified line parallel to the symmetry axis or one straight line located in the middle of two specified lines parallel to and mutually adjacent to the symmetry axis. The relative positions of the outline defining one side and the outline defining the other side with respect to the pixel defining line with respect to the symmetry axis of the figure are also symmetrical, and the pixels included in each outline are symmetrical axes. , And the number of pixels is the same, and dot data for displaying a figure symmetrically is obtained. In the case of a graphic having a convex curved portion, the convex curved portion is displayed by two or more pixels that are continuous in a direction orthogonal to the convex direction due to the parallel movement of the outline data. Is not displayed by only one pixel, and dot data which is displayed in a smooth shape without protrusions can be obtained.

As described above, according to the data conversion device according to the present invention, a figure for which it is necessary to guarantee the symmetry is displayed symmetrically by attaching the axis designation data and translating the outline data so as to be symmetrical. Dot data that can be obtained and that has a convex curved portion and for which smoothness needs to be guaranteed is displayed smoothly by moving the outline data with convex direction designation data attached Can be obtained. Correction of the outline data is performed only by necessary processing according to the purpose of the correction, and the translation and compression of all the figures are performed as in the data conversion device described in JP-A-60-39280. Since the enlargement process is not performed uniformly, the time required for data conversion can be reduced.

It should be noted that the symmetry of the displayed graphic can always be guaranteed by only the parallel movement of the outline data, regardless of the shape of the graphic. On the other hand, the smoothness of the convex portion of the displayed graphic cannot always be guaranteed. For example, for a figure such as the letter O, which is symmetric and has smooth convex parts on both sides of the axis of symmetry, the outline of the figure is simultaneously obtained for both of the two convex parts only by parallel movement of the outline data. This is because it may not be possible to translate the figure so that two or more consecutive pixels are included in the figure. Therefore, with respect to a graphic having a symmetrical and smooth convex portion, the emphasis is placed on the symmetry rather than the smoothness, so that the appearance is improved.In the present invention, at least dot data for displaying the graphic symmetrically is obtained. The outline data is translated. However, also in the present invention, the guarantee of smoothness is not excluded. For a symmetrical figure having smooth convex portions on both sides of the axis of symmetry, data indicating the fact is attached in advance. , By compressing and extending the outline data based on the instruction data,
It is possible to obtain display dot data in which both symmetry and smoothness are guaranteed.

Further, instruction data is added to a figure whose outline data is to be corrected, and this data is simple data indicating the direction of the symmetry axis or the direction of the convexity, and is described in JP-A-61-51189. As compared with the case where a large number of correction data are added to each figure as in the data conversion device of the above, the amount of data can be reduced, and dot data that can guarantee symmetry and smoothness with a small amount of data can be obtained quickly. be able to.

Embodiment Hereinafter, a case where the present invention is applied to a device that converts outline data into dot data in a laser printer that prints characters such as characters and symbols will be described in detail with reference to the drawings.

FIG. 2 is a diagram mainly showing a part related to data conversion in a control circuit of the laser printer. The microcomputer unit 10, which forms the main part of the control circuit, includes a CPU 12, a character ROM 14, a program ROM 16, a text memory 18, a working memory 20, a correction data memory 22, and an intersection coordinate memory 2.
4, a dot data memory 26 is provided. These CPUs 12 and the like are connected by a bus 28, and an input device 30 is connected to the bus 28.
And the printing unit 32 are connected. The input device 30 inputs necessary data to the microcomputer unit 10, and the printing unit 32 is a unit that performs printing by a laser printing method based on a command from the microcomputer unit 10. The resolution of this laser printer is 300 dots / inch.

As shown conceptually in FIG. 3, the CPU 12 includes a data reading section 34, a data correcting section 36 for correcting outline data, and an x at an intersection of a character outline and an x-direction defining line x on a pixel screen described later. An intersection calculation unit 38 for obtaining coordinates, a data setting unit 40 for setting dot data, and the like are provided. The text memory 18 stores print data composed of code data input from the input device 30,
The working memory 20 stores data necessary for executing a program. The intersection coordinate memory 24 stores the x coordinate of the intersection obtained by the intersection calculation unit 38, and the dot data memory 26 stores the dot data set based on the x coordinate stored in the intersection coordinate memory 24. Is stored.

The character ROM 14 stores outline data of characters such as alphabets and other characters and symbols, and instruction data for instructing parallel movement of the outline data. The coordinate plane that determines the outline of the character is
As shown in FIG. 4, the vertical (Y axis) and horizontal (X axis)
It has a size of 1000 × 1000. Uppercase letters of the alphabet are drawn using the Y-axis coordinate values between 200 and 1000, and lowercase letters are drawn using the values between 0 and 200. In the X-axis direction, the center of the coordinate plane is matched with the center of the character.
When the outline of the character is designed on such a coordinate plane, as shown by taking the convex curve 44 as an example, the character constituent line constituting the character has a width,
Surrounded by 46. The outline data is created for each of a plurality of line elements forming the outline of the character, and includes the type of the line element, the coordinates of each end point, and the like. The coordinates of these points are sequentially stored along a fixed direction (indicated by an arrow in the figure) defined on the outline 46, and the two points at both ends of each line element are stored first. The point is the start point, and the point stored later is the end point. Outline data is
If the line element is a straight line, it contains the straight line data and the coordinates of the start and end points; if it is a curve, it contains the curve data, the function formula of the curve and the coordinates of the start point, end point, and auxiliary points; It includes the arc data and the coordinates of the start point, end point, and center point of the circle. The outline data also includes the number N of line elements constituting each character. The instruction data will be described later.

In this laser printer, the conversion of outline data into dot data is performed using the pixel screen 50 shown in FIG. 5 and assuming that the outline of the character is superimposed on the pixel screen 50. The pixel screen 50 is a computational one for converting outline data into dot data, but is shown here as an actual one for easy understanding. The pixel here is a minimum printing unit when printing is performed by the laser, and the pixel screens 50 are orthogonal to each other in one plane, are parallel to the X axis and the Y axis, and the like. Pixels are defined by a plurality of pixel dividing lines p (shown by solid lines in the figure) provided at intervals, and in the present embodiment, the pixels are square. Also, passing through the pixel center point,
An x-direction defining line x and a y-direction defining line y (shown by broken lines in the figure) are set in parallel with the X axis and the Y axis, respectively. A coordinate value indicating a position on the pixel screen 50 is attached to the pixel dividing line p, and an x-direction defining line x and a y-direction defining line y
Can be represented by an x coordinate value and a y coordinate value, respectively. The dot data for printing or not is formed for each pixel, but in this laser printer, a dot is formed at a pixel including the pixel center point within the outline of the character. The data is set to 1. Note that the pixel may have a rectangular shape or another shape.

The pixel screen 50 is assumed to correspond to the printing surface of the printing paper, but FIG. 5 shows only a portion near the origin. Therefore, when the outline of the character is superimposed at an arbitrary position on the pixel screen 50, the coordinate value of the pixel division line p is an appropriate integer for the value assigned to the pixel division line p in FIG. Each value is added.

In addition, this laser printer can display characters of 4.8 points, 10 points, 12 points, 20 points, 24 points, and 30 points.
It can be printed in any size such as points, and the coordinate values of the contour created on the 1000 × 1000 coordinate plane are converted according to the print size. The conversion of coordinate values is performed by assuming a coordinate plane representing the length of one side of one pixel as 1 on the pixel screen 50, and the character at a certain point is C × C
If represented by pixels, multiplying C / 1000 by the coordinate value of the point that determines the contour on the 1000 × 1000 coordinate plane will give the coordinate value on the coordinate plane assumed on the pixel screen 50. is there. Here, a case in which one character performs printing at 4.8 points represented by 20 × 20 pixels will be described. The numbers attached to the pixel division lines p of the pixel screen 50 in FIG. 5 are the coordinate values in this case. The number in parentheses is a number that designates the position of each pixel on the entire pixel screen 50, and is assigned to one pixel as 1.
The combination of the number specifying the position in the X-axis direction and the number specifying the position in the y-axis direction allows the pixel screen 50 of the pixel to be displayed.
The position on the top can be specified. For example, a pixel defined by a pixel division line p having an x coordinate value of 3,4 and a pixel division line p having a y coordinate value of 2,3 can be designated by (3,2). When the outline of the character is superimposed on the pixel screen 50, the coordinate value of the reference point of each character on the pixel screen 50 is also determined based on the print position data, and the coordinate value of the obtained reference point is determined. Superposition is performed using the converted coordinate values.

The convex curve 44 is a symmetry axis parallel to the X axis as shown in FIG.
The character has 54 and is convex in the positive direction of the X-axis. When such convex curves 44 are superimposed on the pixel screen 50, it is assumed that they are superimposed as shown in FIG. In this case, dots are formed as shown by hatched circles in FIG. 6 (b). As is clear from this figure, the dots are formed asymmetrically with respect to the axis of symmetry 54 and have a convex curve. Only one dot protrudes in the direction orthogonal to the direction of the 44 protrusions, and the appearance is poor. Therefore, in the present data conversion apparatus, the instruction data indicating whether or not the outline data is corrected is stored in the character ROM 14 in a pair with the outline. And, in the program ROM 16, along with various programs necessary for printing,
A data conversion program having a function of correcting outline data, which is shown in the flowcharts of FIGS. 7 and 8, is stored to ensure the symmetry or smoothness of the character.

The instruction data includes data instructing correction of outline data and data instructing no correction. The data for instructing the correction include the maximum value x max, y max, minimum value x min, y min of the x coordinate and y coordinate of the character, and the data indicating the direction of the symmetry axis or the convex direction of the convex curved part. Consists of The data indicating the direction of the symmetry axis is X
If it has a symmetry axis parallel to the axis, it is X-axis instruction data, and if it has a symmetry axis parallel to the Y-axis, it is Y-axis instruction data. In addition, the data indicating the convex direction of the convex curved portion has rightward data when the character has a convex curved portion convex in the positive direction of the X axis, and has a convex curved portion convex in the negative direction of the X axis. In this case, the data is leftward data, when there is a convex curved portion that is convex in the positive direction of the Y axis, it is upward data, and when it has a convex curved portion that is convex in the negative direction of the Y axis, it is downward data. Accordingly, in the case of the convex curve 44, the instruction data including the maximum value and the minimum value of the x-coordinate and the y-coordinate, the X-axis instruction data, and the rightward data are paired with the outline data of the convex curve 44 in the character ROM 14. It will be remembered.

Hereinafter, the conversion of outline data to dot data will be described using the convex curve 44 as an example. In this conversion, two coordinates of intersections between the outline of the character and the x-direction defining line x are obtained for each character constituent line, and dot data between the two intersections (including the intersections) is displayed at once. Is set to 1. Since the printing is not essential for understanding the present invention, a detailed description thereof will be omitted. However, in this laser printer, printing is performed for each page. Data of one page is read out of the document data stored in the text memory 18, and outline data of characters constituting the data is converted into dot data and printing is performed.

First, after the outline data of the character to be processed is read in step S1 in FIG. 7 (hereinafter abbreviated as S1; the same applies to other steps), instruction data paired with the outline data is read in S2. Is determined, and it is determined whether or not the instruction data read in S3 is data instructing no correction of the outline data. Since the X-axis instruction data and the rightward data are stored for the convex curve 44, the determination in S3 is NO.
And S4 is executed. In S4, it is determined whether or not the read instruction data includes the X-axis instruction data.
This determination is YES, and the correction amount of the outline data is calculated in S5. As shown in FIGS. 9 (a) and 9 (b), a character having a symmetry axis parallel to the X-axis becomes farther from the symmetry axis with respect to the symmetry axis if the symmetry axis matches the x-direction defining line x. The relative positions of the contour lines that define the portion where the y-coordinate value increases and the portion where the y-coordinate value decreases become the same with respect to the pixel screen 50, and the positions of the pixels included in the contour lines are changed. The character can be displayed symmetrically with respect to the symmetry axis by setting the dot data corresponding to these pixels to be data representing the existence of the character by becoming symmetrical with respect to the symmetry axis and having the same number of pixels. Therefore, the outline data may be modified by modifying the y-coordinate value of the coordinates constituting the outline data so that the symmetry axis coincides with the x-direction defining line x. In S5, FIG.
As shown in the figure, y of the x-direction defining line x (shown by a broken line in the figure) adjacent to the side where the y coordinate value increases with respect to the symmetry axis 54
Correction amount by subtracting the y coordinate value of the symmetry axis 54 from the coordinate value
l ₁ is calculated. The y coordinate value of the symmetry axis 54 is an intermediate value between the maximum value and the minimum value of the y coordinate. In S6, the y coordinate values of all coordinates of the outline data defining the convex curve 44 are
l ₁ is added, and the corrected y coordinate value is stored in the correction data memory 22 together with the x coordinate value. With this correction the convex curve
The reference numeral 44 is superimposed on the pixel screen 50 at the position shown in FIG. 9A, so that dots are formed symmetrically with respect to the symmetry axis 54 as shown in FIG. 9B. When the symmetry axis 54 and the x-direction defining line x match, the correction amount is 0, and the coordinates forming the outline data are stored in the correction data memory 22 in S6.

Next, S12 is executed, and the read instruction data is Y
It is determined whether or not the data includes the axis instruction data. Convex curve
Since 44 is not a character having a symmetry axis parallel to the Y axis, S12 is NO, and a determination is made in S15 as to whether or not the character has a rightwardly convex convex portion. This determination is YES and S
At 16, the amount of correction of the outline data is calculated.
Correction of the outline data having the convex convex portion in the rightward direction is performed by correcting the maximum value of the x-coordinate, that is, the pixel adjacent to the pixel division line p parallel to the Y-axis and having the x-coordinate value increasing. This is performed by matching with the division line p. As shown in FIG. 9B, when the local maximum point of the convex curve 44 coincides with the x-direction defining line x, the tip of the convex curve 44 is displayed by one pixel. On the other hand, if the local maximum point coincides with the pixel dividing line p as shown in FIG. 10 (a), the image is displayed by three pixels as shown in FIG. 10 (b). At a position slightly in front of the division line p and coincident with the next x-direction definition line x, the image is displayed by five pixels. However, with 5 pixels, a convex curve
44 is displayed rather flat, and the amount of movement of the outline data is large, which is not optimal. If it is made to coincide with the central pixel division line p of the adjacent x-direction definition line x,
The convex curve can be displayed smoothly with a small movement amount of the outline data.

Therefore, in S16, as shown in FIG. 9 (a), the maximum value of the x coordinate of the convex curve 44 is determined by the x coordinate value of the pixel division line p adjacent to the side where the x coordinate value increases with respect to the maximum value. correction amount l ₂ is calculated by subtracting from step S17 correction amount l ₂
Is added to the x-coordinate values of all the coordinates of the outline data defining the convex curve 44, and the outline data is corrected. After the outline data is corrected in this way, the setting of dot data is performed in S20 and subsequent steps.

If the character does not have a symmetry axis parallel to the X axis, S4 becomes NO, and in S7, it is determined whether or not the character has an upwardly convex convex portion.
If it is, a determination is made in S10 as to whether or not there is a downwardly convex portion. If the character has an axis of symmetry parallel to the X-axis, it is not determined whether the character is convex upward or downward, but this is because the X-axis instruction data, the upward data, and the downward data are different. This is because instruction data of the same one character is not used.

As in the case of a convex curve 56 shown in FIG. 11 (a), in the case of a character which is symmetric about a symmetry axis 58 parallel to the Y axis and has a downwardly convex convex curved portion, FIG. In some cases, the image is displayed asymmetrically with a protrusion at the protruding end as shown by drawing a dot. In the case of this convex curve 56, S10 becomes YES, S11 and S9 are executed, and the minimum value of the y coordinate of the convex curve 56 is set to X
A shaft parallel pixel partition line p, the correction amount l ₃ so as to match the pixel partition line p which is adjacent to the side y-coordinate value increases relative to the minimum value of the y coordinate is calculated, the outline data Will be modified. As a result, the convex curve 56 is superimposed on the pixel screen 50 as shown in FIG. 12 (a), so that a smooth shape without projections is displayed as shown in FIG. 12 (b).

Further, in the case of a character having a symmetry axis 58 parallel to the Y axis, such as the convex curve 56, S12 is YES, and the correction amount of the outline data is calculated in S13. The correction of the outline data of the character having the symmetry axis parallel to the Y axis is performed by matching the symmetry axis with the y direction defining line y adjacent to the side where the x coordinate value increases. Therefore, after the calculated correction amount l ₄ shown in Figure 12 in S13 (a), fixes the outline data in S14, the pixel screen as it positive contour curve 56 by shown in Figure 13 (a) It is superimposed on 50 and displayed symmetrically with respect to the axis of symmetry 58 as shown in FIG. 13 (b).

Although not shown, if the instruction data includes upward data, S7 becomes YES, and the correction amount of the outline data is calculated in S8. The correction of the outline data having the upwardly convex convex portion is performed by correcting the maximum value (maximum point) of the y-coordinate with a pixel which is adjacent to the pixel division line p parallel to the X-axis and on which the y-coordinate value increases. This is performed by matching with the division line p. Therefore, in S7, the pixel division line p
The correction amount is calculated by subtracting the maximum value of the y-coordinate of the convex portion from the y-coordinate value of, and the correction amount is added to the y-coordinate values of all the coordinates constituting the outline data in S8.

Further, in the case of a character having a convex curved portion that is convex in the left direction, S18 is YES, the correction amount is calculated in S19, and S
At 17 the outline data is modified. In this case, the correction amount is set so that the minimum value of the x coordinate of the convex portion is made to coincide with the pixel division line p adjacent to the pixel division line p parallel to the Y axis and on the side where the x coordinate value increases. Is calculated, and the outline data is corrected. If the character has an axis of symmetry parallel to the Y axis, it is not determined whether or not the character has a convex curved portion that is convex rightward or leftward. In this case, the outline data of S13 and S14 is not determined. This is because the position of the character in the left-right direction is determined by the correction, and it is not necessary to correct the outline data based on the rightward convexity and the leftward convexity.

If the instruction data is data indicating no correction, S3
Is YES, S4 to S19 are skipped, and dot data is set in S20 and below.

If the outline data is modified as above
After S20 is performed and the count value C of the counter is increased by 1, the x coordinate of the intersection of the outline and the x-direction defining line x is calculated in S21. The position of the x-direction defining line x can be represented by the y-coordinate value of the pixel screen 50, and the x-coordinate value of the intersection with respect to the y-coordinate value is obtained. No.
As shown in FIG. 14, as an example, a case where a line element is a straight line that intersects both the x-direction defining line x and the y-direction defining line y will be described. Although the specified line x intersects at the position indicated by the x mark, the x-coordinate of the intersection is defined not by the x-coordinate of the actual intersection of the x-direction specified line x and the line element, but by the line element The x at the left end of the pixel having the pixel center point (the point marked with a circle in the figure) at the position closest to the actual intersection on the character constituent line side (the shaded part in the figure) Coordinates are adopted. The x coordinate of this intersection coincides with the designated number of each pixel shown in parentheses in FIG. Here, the character constituent line side is the inside of the contour line, and when data specifying each line element of the contour line is stored in the order of turning the character constituent line counterclockwise, the starting point side of each line element This is the area on the left side when viewing the end point side from, and the area on the right side when stored in the order of turning clockwise. If the actual intersection of the x-direction defining line x and the line element coincides with the pixel center point, the x coordinate of the left end of the pixel having the pixel center point is the intersection of the x-direction defining line x and the line element. It is said.

The convex curve 44 is superimposed on the pixel screen 50 as shown in FIG. 5 by correcting the outline data, and the x coordinate value of the intersection with the x direction defining line x is calculated. This calculation is performed for each line element, and the calculated x coordinate value of the intersection is stored in the intersection coordinate memory 24 for each x direction defining line x as shown in FIG. If the x coordinate of the intersection is calculated for one line element, S22 is executed, but the determination is NO, and S20 to S22 are performed until the x coordinate of the intersection is calculated for all the line elements constituting the convex curve 44. Is repeatedly executed. S2 if S22 becomes YES
After the count value C is set to 0 in step 3, the x-coordinates stored in the intersection coordinate memory 24 for each of the x-direction defining lines x are rearranged in ascending order in step S24. And the setting of the dot data is performed. Since two intersection coordinates are determined for each x-direction defining line x for one character constituent line, x
If the coordinates are rearranged in ascending order to form pairs, the character constituent lines always exist between the paired numbers, and the dot data corresponding to the pixels between those numbers is reduced to one at a time. Although it can be set, the x coordinate of the intersection is obtained for each line element in S21, and x
Since the x-coordinate is stored in the intersection coordinate memory 24 in the order in which the coordinates were calculated, the x-coordinate value may be obtained before the smaller line element for the larger line element, and may be stored in the order of the size. This sort is done because it is not always the case. In this embodiment, the dot data is set to 1 also for a pixel whose intersection is the pixel center point.

After the rearrangement of the x coordinate is performed as described above, the setting of the dot data is performed. This setting is performed collectively in units of one byte. The microcomputer unit 10 can process 1-byte data in parallel. Since dot data of one pixel is represented by one bit, dot data of eight pixels are set at a time. This setting is the same as that in the data conversion apparatus described in Japanese Patent Application No. 63-269074 of the applicant of the present invention.
The coordinates are separated for each byte based on the coordinates of the bits for separating one byte (coordinates of the bits for separating between adjacent bytes), and the dots belong to the same byte and correspond to the pixel where the character exists. Data is collectively set to 1.

The x-coordinate obtained for the x-direction defining line x whose position in the y-axis direction is 2 will be described as an example with reference to FIG. The x-coordinate pair (4,5), which is larger than the smaller x-coordinate, is compared with the coordinate 7 of the 1-byte delimiting bit and the larger pixel designation number 4. Since the coordinates of the delimiter are larger, the character constituting line represented by this x coordinate pair is included in one byte, and the dot data respectively corresponding to the x coordinate value pair (4, 5) are combined into one. Is set. In FIG. 16, a hatched circle represents dot data set to 1. If the larger x-coordinate of the pair of x-coordinates is larger than the one-byte delimiting coordinate, the pixel between the delimited x-coordinate and the smaller x-coordinate is included in one byte. After they are collectively set to 1, it is calculated how many groups each having 8 as a unit between the x-coordinate serving as the delimiter and the larger x-coordinate, and the dot data are collectively stored byte by byte. 1
Is set to The dot data set in this way is stored in the dot data memory 26.

As described above, according to the data conversion device of the present embodiment, the outline data is corrected and then converted into dot data, thereby ensuring the symmetry and smoothness of the character. This is performed only for the character in which the instruction data is stored.
By performing only the parallel movement, the outline data is quickly converted to the dot data with a small amount of data.

In addition, the outline data of a character having a convex curved portion is corrected by setting the maximum point and the minimum point to a pixel section adjacent to the side where the x-coordinate value increases even if the convex curved portion is convex on either the positive or negative side of the X axis. This is performed by matching with the line p, so that the local maximum point and the local minimum point coincide with the pixel division line p adjacent to the side where the y coordinate value increases, regardless of whether the convex curved portion is convex on either the positive or negative side of the Y axis. This is done by: Therefore, when the outline data is corrected, all the characters are moved rightward or upward. The maximum point and the minimum point may be made to coincide with another pixel division line p that is close. But,
When adjacent characters each have a convex portion, outline data may be moved in opposite directions, and in such a case, the space between characters is wide,
Alternatively, the distance becomes narrow and the interval varies, and the appearance deteriorates. On the other hand, if the moving direction of the outline data is set to the same according to the direction of the convex portion of the character, even if the adjacent character has a convex portion that is convex in the horizontal direction or the vertical direction, the space between the characters is reduced. It is avoided that the size becomes excessively large or too small, and the deterioration of the display quality is avoided.

As is clear from the above description, in the present embodiment, the portion storing S20 to S24 of the program ROM 14 and the C
The part of the PU 12 that executes these steps, that is, the intersection calculation unit 38 and the data setting unit 40 constitute data conversion means, the character ROM 14 constitutes instruction data storage means, and the part that stores S2 to S19 of the program 14 and the CPU 12 That is, the portion that executes those steps, that is, the data correction section 36 constitutes outline data correction means.

In the above embodiment, simple convex curves 44 and 56 have been described as an example. However, even with alphabets, symmetry and smoothness can be ensured by correcting the outline data as described above. For example, in the case of a character that is not symmetrical, such as the letter P, and has a convex portion only in one direction, the character is translated in parallel in accordance with data indicating the direction of the convex portion, so that a smooth convex portion without protrusions is obtained. Can be obtained.

A character having a symmetry axis parallel to the X axis and the Y axis, such as the letter H, but having no convex portion, can obtain a symmetric display only by translation in two directions.

O in the alphabet is a character having a symmetry axis symmetrical about the X axis and the Y axis, and having a convex curved portion that is convex in the vertical direction and the horizontal direction, respectively. , it can be displayed symmetrically by making it coincide with the y-direction defining line y, but the tip of the convex curved portion may be displayed by one dot. in this case,
If the contour is compressed or stretched so that the maximum point or the minimum point of the protruding curved portion coincides with the pixel dividing line p so that it is displayed by two or more pixels continuous in the direction orthogonal to the direction of the convexity, the symmetry is obtained. While maintaining smoothness.

Further, in the above embodiment, when the character is symmetric, the axis of symmetry is made to coincide with the y-direction defining line y, the x-direction defining line x adjacent to the side where the x-coordinate value or the y-coordinate value increases. The y-direction defining line y adjacent to the side where the x-coordinate value or the y-coordinate value decreases or the x-direction defining line x may be matched, or the adjacent x-direction defining line x or y-direction defining line y
May be matched with the closer line.

Furthermore, when the character is symmetric, the outline data may be corrected by making the axis of symmetry coincide with the pixel division line p. In this way, in a figure that is symmetric and has a convex curved part where the maximum point and the minimum point are located on the axis of symmetry, at least two pixels are always included at the tip of the convex curved part. , Is prevented from protruding only one dot.

Further, when correcting the outline data of a character having a convex curved portion, the local maximum point and the local minimum point may be made to coincide with the pixel division line p requiring only a small amount of movement. May be matched with the pixel division line p.

Furthermore, in the above embodiment, the outline data is corrected regardless of the print size.However, the outline data is corrected only when printing is performed with a size of 12 points or less. Is also good.

In the above embodiment, the outline data is created for each line element. However, the outline data may be constituted by other means, such as by using only coordinates. When represented only by coordinates, for a character composed of a plurality of straight lines, outline data is composed of a group of coordinate data for each line element of the contour, and for a character including a curve, the outline data is necessary to define the curve. The outline data is configured to include a coordinate data group of a plurality of points.

Furthermore, it goes without saying that the present invention can be applied to laser printers for printing figures and printers other than laser printers.
In general, the present invention can be applied to a device other than a printer that needs to convert outline data such as characters and graphics into dot data.

In addition, without departing from the scope of the claims, the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art.

[Brief description of the drawings]

FIG. 1 is a block diagram conceptually showing the configuration of a data conversion device according to the present invention. FIG. 2 is a block diagram showing a control circuit of a laser printer having a data converter according to one embodiment of the present invention. FIG. 3 is a diagram conceptually showing a CPU constituting the control circuit. FIG. 4 is a diagram showing a contour of a convex curve converted by the data conversion device.
FIG. 5 is a diagram showing the convex curve superimposed on the pixel screen. FIG. 6 shows the above convex curve as the symmetry of the pixel screen,
It is a figure showing the state where it overlapped on the position where smoothness is not secured. 7 and 8 show a program RO of the above control circuit.
6 is a flowchart showing a data conversion program among programs stored in M. 9 and 10 are diagrams for explaining the correction of the outline data of the convex curve. FIG. 11, FIG. 12, and FIG. 13 are diagrams for explaining the correction of outline data of a convex curve different from the above-mentioned convex curve. FIG. 14 is a diagram for explaining how to obtain the coordinates of the intersection of a line element constituting the outline of the character converted by the data conversion device and the x-direction defining line x. FIG. 15 is a diagram showing, for each x-direction defining line x, the x-coordinate of the intersection of the contour of the convex curve shown in FIG. 5 and the x-direction defining line x. FIG. 16 is a diagram for explaining the setting of dot data performed based on the x coordinate of the intersection. 10: microcomputer part, 44: convex curve 46: outline, 50: pixel screen 54: symmetry axis, 56: convex curve 58: symmetry axis

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-39280 (JP, A) JP-A-61-51189 (JP, A)

Claims (1)

(57) [Claims] An outline of a figure such as a character or a symbol represented by outline data including coordinate point data representing coordinate values of a plurality of coordinate points and line element data representing a type of a line connecting two coordinate points. Corresponding to pixels included in the outline in a state satisfying a certain criterion, assuming that the pixels are superimposed on a pixel screen that defines pixels by a plurality of defining lines parallel to the X axis and the Y axis that are orthogonal to each other. A data conversion device comprising data conversion means for converting outline data into dot data by setting dot data to data representing the presence of a graphic, wherein the graphic has an axis of symmetry parallel to the X axis or the Y axis. In the case, the axis designation data indicating the axis whose symmetry axis is parallel to the axis, and the figure is one of the positive and negative directions of the X axis or the positive and negative directions of the Y axis. Instruction data storage means for storing instruction data including convex direction instruction data for instructing the direction of the convexity when having a convex curved portion which is smoothly convex in one direction, in association with outline data of the figure; By moving the coordinate values of all the coordinate point data of the outline data associated with the data equally in a direction perpendicular to the axis designated by the axis designation data, the symmetry axis of the figure is symmetrically set. An outline associated with one of the prescribed lines parallel to the axis or one straight line located in the middle between two prescribed lines parallel to the symmetry axis and adjacent to each other, while being associated with the convex direction indicating data By uniformly translating the coordinate values of all the coordinate point data of the data in a direction parallel to the direction designated by the convex direction designation data, The maximum point or the minimum point of the convex curved portion is mutually continuous in the direction orthogonal to the direction designated by the convex direction designation data in the vicinity of the position where the maximum point or the minimum point of the convex curved portion is located. And outline data correction means for positioning dot data respectively corresponding to two or more pixels to be set in data representing the presence of a figure, and correcting the data conversion means by the outline data correction means. A data conversion device for converting outline data into dot data.