JP4594809B2 - Outline font output device, outline font output method, and computer program - Google Patents

Description

  The present invention relates to an outline font output device, an outline font output method, and a computer that can specify a gray density of a contour portion including a corner portion of an outline font and display and output the same with a smooth font while suppressing consumption of computer resources. Regarding the program.

  With the rapid development of DTP technology in recent years, fonts used in word processors, personal computers, and the like are required to be displayed or printed more clearly and smoothly. Fonts used in word processors, personal computers, and the like can be broadly classified into bitmap fonts and outline fonts.

  The outline font is drawn by forming an outline and painting a region surrounded by the outline. Therefore, even when the character size is changed or rotated, high-quality characters with less jaggy can be displayed or printed.

  Data representing the outline font is stored in an outline font dictionary stored in a hard disk, ROM, or the like. When a single character is drawn, outline font data corresponding to the character is read from the outline font dictionary, subjected to a predetermined process, and then drawn by a display device or a printing device.

In the conventional outline font, for example, a closed region is generated by approximating a contour clockwise, using a cubic Bezier curve function, a B-spline function, or the like. Then, for each pixel through which the outline forming the closed region passes, the area ratio of the closed region included in the pixel is calculated using a ratio such as the number of dots included in the pixel, and the calculated area ratio is calculated. The gray density is changed accordingly. Thereby, the jagged part which is likely to occur in the outline can be improved, and the outline of the font can be easily changed (see Patent Documents 1 and 2).
Japanese Patent No. 2774653 JP 2002-351451 A

  However, in the conventional outline font display method described above, many broken lines are generated by approximating the outline with short straight lines, and the calculation processing load is reduced by approximating the outline with the broken line. When displaying the corner portion of the outline of a character, the processing load for calculating the area of the area surrounded by the broken line cannot be reduced, and it takes a considerable time to display or print the outline font. There was a problem of fear.

  The present invention has been made in view of such circumstances, and performs contour approximation of a contour line and reduces the calculation processing load in calculating the area of the corner portion of the contour line of a character to display or print an outline font. It is an object of the present invention to provide an outline font output device, an outline font output method, and a computer program that can reduce the time required for the above.

In order to achieve the above object, an outline font output device according to a first aspect of the present invention approximates a closed curve indicating the outline of an outline font by a polygonal line, and determines a gray density of a pixel having a corner portion of the approximate polygonal line as a predetermined value including the pixel. An outline font output device that outputs an outline font by specifying a ratio of an area occupied by a portion of a font area that is inside the polygonal line in a unit area, wherein the unit area is rectangular, and an approximate polygonal line and Means for determining whether one side of the unit region intersecting is the long side or the short side of the unit region, and the distance from the long side or short side to the corner portion and the intersection on the long side or short side means for identifying a distance from the sides, based on the specified distance, one or of the unit area facing the corner portions of the polygonal line approximating in the unit area Means that to calculate the area of the font area surrounded by the number of sides and the fold lines, characterized in that it comprises a means for obtaining a ratio of the area calculated for the area of the unit area as the percentage.

In the outline font output device according to the second aspect of the present invention, the closed curve indicating the outline of the outline font is approximated by a polygonal line, and the gray density of the pixel in which the corner portion of the approximate polygonal line exists is determined in a predetermined unit area including the pixel. identified in the ratio of the area occupied by the inner and is font area portion of the polygonal line, a outline font output device for outputting the outline font, the unit region is square, the unit region intersecting with polygonal line approximates distance to the angle portion from one side, and means for identifying the distance from the other side of the intersection on the one side, and means that to calculate the area of the font area based on the distance specified, the unit area Means for determining the ratio of the calculated area to the area as the ratio .

In the outline font output method according to the third aspect of the invention, the closed curve indicating the outline of the outline font is approximated by a polygonal line, and the gray density of the pixel in which the corner portion of the approximated polygonal line exists is determined in a predetermined unit area including the pixel. An outline font output method for specifying an area ratio occupied by a portion of a font area inside the polygonal line and outputting an outline font, wherein the unit area is rectangular and intersects with an approximate polygonal line Determine whether one side is the long side or short side of the unit area, and specify the distance from the long side or short side to the corner and the distance from the other side to the intersection on the long side or short side and, based on the specified distance, surrounded by one or more sides and polygonal faces sandwiching the corner portion and the font region of the polygonal line approximating in the unit area Calculating the area of the font area, and obtains the ratio of the area calculated for the area of the unit area as the percentage.

In the outline font output method according to the fourth aspect of the present invention, the closed curve indicating the outline of the outline font is approximated by a polygonal line, and the gray density of the pixel in which the corner portion of the approximate polygonal line exists is determined in a predetermined unit region including the pixel. An outline font output method for specifying an area ratio occupied by a portion of a font area inside the polygonal line and outputting an outline font, wherein the unit area is a square and the unit area intersecting the approximate polygonal line Specify the distance from one side to the corner part and the distance from the other side of the intersection on the one side, calculate the area of the font area based on the specified distance , and calculate the area for the area of the unit area The ratio is obtained as the ratio .

According to a fifth aspect of the present invention, there is provided a computer program that approximates a closed curve indicating an outline of an outline font that passes through a rectangular unit region by a polygonal line, and includes the gray density of a pixel having a corner portion of the approximate polygonal line. A computer program that can be executed by a computer that outputs an outline font that is specified by a ratio of an area occupied by a portion of a font area that is inside the polygonal line within a predetermined unit area, the computer being approximated Means for determining whether one side of the unit region intersecting with the polygonal line is a long side or a short side of the unit region, a distance from the long side or the short side to the corner portion, and an intersection on the long side or the short side means for identifying a distance from the other side, based on the distance was especially boss, corner portions and font territory of polygonal line approximating in the unit area One or more sides and means to calculate the area of the font area surrounded by broken line of the unit areas sandwiching opposite the means for determining the ratio of the area calculated for the area of the unit area as the percentage, and calculated It functions as a density specifying means for specifying the gray density of the pixel based on the ratio .

According to a sixth aspect of the present invention, there is provided a computer program that approximates a closed curve indicating the outline of an outline font that passes through a square unit area by a polygonal line, and includes the gray density of a pixel having a corner portion of the approximate polygonal line. A computer program that can be executed by a computer that outputs an outline font that is specified by a ratio of an area occupied by a portion of a font area that is inside the polygonal line within a predetermined unit area, the computer being approximated Means for specifying a distance from one side of the unit area intersecting the polygonal line to the corner portion, a distance from the other side of the intersection on the one side, and means for calculating the area of the font area based on the specified distance , Means for determining the ratio of the calculated area to the area of the unit region as the ratio, and Characterized in that to function as the concentration specifying means for specifying the gray levels of pixels based on the ratio.

In the first invention, the third invention, and the fifth invention, the closed curve indicating the outline of the outline font is approximated by a polygonal line, and one or more facing the corner part in the rectangular unit region where the corner part of the approximated polygonal line exists The area of the font region surrounded by the side is calculated, and the gray density of the pixel of the font region in the unit region is specified according to the calculated area. As a result, the processing load can be reduced, and since the area of the font area surrounding the corner portion of the approximated line segment existing in the unit area is calculated, the pixel gray of the font area in the unit area is calculated. It is possible to reduce the calculation processing load related to area calculation for specifying the density, and it is possible to shorten the time until the font is displayed or printed.
Further, in the present invention, it is determined whether one side of the unit region intersecting the approximate polygonal line is the long side or the short side of the unit region, and the relative position of the corner portion with respect to the long side or the short side, that is, the distance from the one side. The area of the font area is calculated based on the distance from the long side or short side of the intersection. As a result, the area can be calculated with relative coordinates according to which side intersects the vertical and horizontal sides, and the calculation processing load related to area calculation for specifying the gray density of the pixel in the font area in the unit area is reduced. It is possible to reduce the time until the font is displayed or printed.

In the second invention, the fourth invention, and the sixth invention, the closed curve indicating the outline of the outline font is approximated by a polygonal line, and one or a plurality of opposing corner parts in a rectangular unit region where the corner part of the approximated polygonal line exists The area of the font region surrounded by the side is calculated, and the gray density of the pixel of the font region in the unit region is specified according to the calculated area. As a result, the processing load can be reduced, and since the area of the font area surrounding the corner portion of the approximated line segment existing in the unit area is calculated, the pixel gray of the font area in the unit area is calculated. It is possible to reduce the calculation processing load related to area calculation for specifying the density, and it is possible to shorten the time until the font is displayed or printed.
Further, in the present invention, the unit region is a square, and is surrounded by one or more sides facing the corner portion of the approximate polygonal line based on the relative position based on one side of the unit region that intersects the approximate polygonal line. The area of the font area is calculated. As a result, the area can be calculated with relative coordinates based on one side of the unit area, and the processing load related to area calculation for specifying the gray density of the pixel of the font area in the unit area can be reduced. It is possible to shorten the time until the font is displayed or printed.

According to the present invention, it is possible to reduce the processing load for displaying the corner portion of the outline of the outline font. In addition, since the area is calculated based on the relative coordinates from the side intersecting with one side of the unit area including the corner part pixel, the area calculation for specifying the gray density of the pixel of the font area in the unit area is concerned. The calculation processing load can be reduced, and the time until the font is displayed or printed can be shortened.

(Embodiment 1)
Hereinafter, an outline font output apparatus according to Embodiment 1 of the present invention will be specifically described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an outline font output device 10 according to Embodiment 1 of the present invention. As shown in FIG. 1, the outline font output device 10 includes at least a CPU (central processing unit) 11, a storage unit 12, a ROM 13, a RAM 14, a portable storage medium 2 such as a DVD or a CD, an input. It comprises means 16, display means 17 for outputting display data, and printing means 18 for printing print data.

  The CPU 11 is connected to the above-described hardware units of the outline font output device 10 via the internal bus 19, and controls the above-described hardware units and also stores a processing program stored in the storage unit 12, for example, Various software functions are executed in accordance with a program that functions as a word processor, an outline font rasterization processing program, and the like.

  The storage means 12 is a built-in fixed-type storage device (hard disk), and is a processing program necessary for functioning as the outline font output device 10 obtained from a portable recording medium 2 such as a DVD or CD-ROM, for example A software module that functions as a word processor is stored. The storage unit 12 stores not only the processing program but also font data of an outline font, for example, in the font data storage unit 121 and the gray density for each unit pixel in the gray density storage unit 122, respectively.

  The ROM 13 is configured by a flash memory, SRAM, or the like, and stores font data of outline fonts, for example. Further, a character code or the like may be stored. The RAM 14 is composed of a DRAM or the like, and stores temporary data generated when software is executed.

  The auxiliary storage unit 15 uses a portable recording medium 2 such as a CD or a DVD, and downloads a program, data, or the like to be processed by the CPU 11 to the storage unit 12. It is also possible to write the data processed by the CPU 11 for backup.

  The input means 16 is a pointing device such as a mouse that moves a cursor displayed on the screen, or a keyboard that inputs text data by keystroke on the screen.

  The display unit 17 includes a liquid crystal display (LCD), a display display (CRT) that displays display data generated based on the font data of the outline font stored in the font display data storage unit 121 of the storage unit 12 or the ROM 13. ) And the like. The printing unit 18 is a printing device such as a laser printer or an ink jet printer that prints out print data generated based on the font data of the outline font stored in the font data storage unit 121 of the storage unit 12 or the ROM 13. .

  FIG. 2 is a flowchart showing a processing procedure of the CPU 11 of the outline font output device 10 according to the first embodiment of the present invention. The CPU 11 of the outline font output device 10 reads the font data stored in the font data storage unit 121 of the storage unit 12 or the ROM 13 (step S201), extracts the character code of the character to be displayed or printed from the ROM 13, Outline data that constitutes the contour is calculated (step S202).

  The CPU 11 approximates the calculated outline data as a set of short line segments as a polygonal line (step S203), and specifies the coordinates of the pixels constituting the corner portion of the outline font (step S204). The pixel constituting the contour is a unit pixel composed of a rectangle having a short side of 8 bits (256 dots) and a long side of 16 bits (512 dots), and the following calculation is performed with the short side as a unit length, for example, “1”. To do. The aspect ratio of the unit pixel is not limited to 1: 2 as described above, and may be 1: α (α is an arbitrary real number).

  FIG. 3 is an exemplary diagram of processing for approximating outline data to a polygonal line. In the first embodiment, the pixel coordinates of the contour are specified using unit pixels composed of a rectangle of 256 (dots) × 512 (dots) having a short side of 8 bits and a long side of 16 bits. Then, the following calculation is executed with the length of the short side of the unit pixel as the unit length ‘1’. As shown in FIG. 3, a specific unit pixel is set as a start point “0”, unit pixels including an outline are sequentially specified clockwise, and the coordinates of the unit pixel are set up to an end point “m” (m is a natural number) of a closed curve indicating the outline. Identify.

  CPU11 calculates the area of a font display part about the unit pixel in which the corner | angular part of a font display part is contained (step S205). FIG. 4 is an exemplary diagram of unit pixels that are targets for calculating the area of the font display portion. The lower left vertex of the unit pixel is the origin (0, 0), the length of the short side is 1.0, and α = 2.0. As shown in FIG. 4, when a corner portion is included in a unit pixel, a point (xk, yk) in the unit pixel and points (xp, yp), (xq, yq) before and after passing through the unit pixel Thus, the area of the font display portion in the unit pixel can be obtained.

  The CPU 11 first obtains the coordinates of the point where the line segment approximated by each broken line and the side of the unit pixel intersect. FIGS. 5A to 5D are polygonal line approximations when light is emitted from a point (xk, yk) in a unit pixel toward an external point (xq, yq) when the long side of the unit pixel is horizontal. It is a figure which shows the coordinate of the point which the line segment and the side of a unit pixel crossed. In FIG. 5, regions 1 to 4 are classified based on which side of the unit pixel intersects the line segment approximated by the broken line. FIG. 5A is an exemplary diagram in the case of the region 1, and the point where the outline font intersects is (α, yf).

  FIG. 5B is an exemplary diagram in the case of the region 2, and the intersecting point is (α−xf, 1). Note that xf is a remainder portion of α at the intersecting point by α. FIG. 5C is an exemplary diagram in the case of the region 3, and the intersecting point is (0, 1-yf). FIG. 5D is an exemplary diagram in the case of the region 4, and the intersecting point is (xf, 0). In FIG. 5, the line segment approximated by a polygonal line and the side of the unit pixel intersect when emitted from the vertex (xk, yk) constituting the corner portion in the unit pixel toward the external point (xq, yq). Although the coordinates of the point to be described are explained, a line segment and unit pixel approximated by a polygonal line when incident from an external point (xp, yp) toward a vertex (xk, yk) constituting a corner portion in the unit pixel Region classification can also be performed in the same manner for the coordinates of the point where the side of the line intersects.

  6A to 6D show broken line approximations when light is emitted from a point (xk, yk) in a unit pixel toward an external point (xq, yq) when the long side of the unit pixel is vertical. It is a figure which shows the coordinate of the point which the line segment and the side of a unit pixel crossed. In FIG. 6, regions 1 to 4 are classified based on which side of the unit pixel intersects the line segment approximated by the broken line. FIG. 6A is an exemplary diagram in the case of the region 1, and the point where the outline font intersects is (α, yf).

  FIG. 6B is an exemplary diagram in the case of the region 2, and the intersecting point is (1-xf, α). Note that xf is a remainder portion of the intersecting point with an x coordinate of 1.0. FIG. 6C is an exemplary diagram in the case of the region 3, and the intersecting point is (0, 1.0-yf). FIG. 6D is an exemplary diagram in the case of the region 4, and the intersecting point is (xf, 0). In FIG. 5, the line segment approximated by a polygonal line and the side of the unit pixel intersect when emitted from the vertex (xk, yk) constituting the corner portion in the unit pixel toward the external point (xq, yq). Although the coordinates of the point to be described are explained, a line segment and unit pixel approximated by a polygonal line when incident from an external point (xp, yp) toward a vertex (xk, yk) constituting a corner portion in the unit pixel Region classification can also be performed in the same manner for the coordinates of the point where the side of the line intersects.

  After performing the region classification, the CPU 11 calculates the area of the part surrounded by one or more sides facing the vertex (xk, yk) constituting the corner part in the unit pixel (step S205). An area ratio for each unit pixel is calculated based on the area (step S206), and a gray density for each unit pixel is calculated (step S207).

  Specifically, by executing the processing shown in FIG. 7 or FIG. 8, the area of the part surrounded by one or more sides facing the vertex (xk, yk) constituting the corner part in the unit pixel is determined. calculate. The CPU 11 calculates a difference between a region where a line segment approximated to a polygonal line enters a unit pixel and a region where a line segment approximated to a polygonal line exits from the unit pixel, and sandwiches the vertices (xk, yk) constituting the corner portion 2 Specify which side of a unit pixel a line segment passes through. 7A to 7E, when a region where a line segment approximated to a unit pixel is incident on a polygonal line is on the long side of the rectangle, a line segment approximated to a polygonal line is emitted from the incident region and the unit pixel. It is a figure which shows the method of calculating | requiring the area of a font display part according to difference value (DELTA) R with a region. The difference value ΔR is calculated by subtracting the region where the line segment approximating the polygonal line enters the unit pixel from the region where the line segment approximating the polygonal line is emitted from the unit pixel, and the calculation result becomes a negative value. When ΔR = '-3', ΔR = '1', when ΔR = '-2', ΔR = '2', when ΔR = '-1', ΔR = '3' Convert each one.

  FIG. 7A shows a case where the difference value ΔR is “0”, and a line segment approximating the polygonal line is emitted from the unit pixel from the x coordinate x1 of the point where the line segment approximating the polygonal line enters the unit pixel. It is a figure which shows the method of calculating | requiring the area of the font display part when the x coordinate x2 of a point is larger. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 1).

(Equation 1)
A = D2 × (x2−x1) / 2

  FIG. 7B shows a case where the difference value ΔR is “0”, and a line segment approximating a polygonal line is emitted from the unit pixel from the x coordinate x2 of the point where the line segment approximating the polygonal line enters the unit pixel. It is a figure which shows the method of calculating | requiring the area of the font display part when the x coordinate x1 of a point is smaller. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 2).

(Equation 2)
A = α−D2 × (x2−x1) / 2

  FIG. 7C is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “1”. Since the right side of the moving direction of the broken line is displayed in gray, the area A of the font display portion (hatched portion) is calculated by (Equation 3).

(Equation 3)
A = (D2 × (α−x1) + D1 × y1) / 2

  FIG. 7D is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “2”. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 4). Note that x3 is a value obtained by subtracting from x the x coordinate x2 of a point where a line segment approximated by a broken line is emitted from a unit pixel.

(Equation 4)
A = ((D2 × (α−x1) + D1 + (1.0−D2) × x3)) / 2

  FIG. 7E is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “3”. Since the right side in the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 5). Note that y3 is a value obtained by subtracting from 1.0 the y coordinate y1 of the point where a line segment approximating a polygonal line from the unit pixel is emitted.

(Equation 5)
A = α− (D2 × x1 + (α−D1) × (1.0−y3)) / 2

  In FIGS. 8A to 8E, when a region where a line segment approximated to a unit pixel is incident on a polygonal line is on the short side of the rectangle, a line segment approximated to a polygonal line is emitted from the incident region and the unit pixel. It is a figure which shows the method of calculating | requiring the area of a font display part according to difference value (DELTA) R with a region.

  FIG. 8A shows a case where the difference value ΔR is “0”, and a line segment approximating a polygonal line is emitted from the unit pixel from the x coordinate x1 of the point where the line segment approximating the polygonal line enters the unit pixel. It is a figure which shows the method of calculating | requiring the area of the font display part when the x coordinate x2 of a point is larger. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (hatched portion) is calculated by (Equation 6).

(Equation 6)
A = D2 × (x2−x1) / 2

  FIG. 8B shows a case where the difference value ΔR is “0”, and a line segment approximating the polygonal line is emitted from the unit pixel from the x coordinate x2 of the point where the line segment approximating the polygonal line enters the unit pixel. It is a figure which shows the method of calculating | requiring the area of the font display part when the x coordinate x1 of a point is smaller. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 7).

(Equation 7)
A = α−D2 × (x2−x1) / 2

  FIG. 8C is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “1”. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 8).

(Equation 8)
A = (D2 × (1.0−x1) + D1 × y1) / 2

  FIG. 8D is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “2”. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 9). Note that x3 is a value obtained by subtracting x coordinate x2 of a point where a line segment approximated by a broken line from a unit pixel is emitted from 1.0.

(Equation 9)
A = ((D2 × (1.0−x1) + α × D1 + (α−D2) × x3)) / 2

  FIG. 8E is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “3”. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (hatched portion) is calculated by (Equation 10). Note that y3 is a value obtained by subtracting the y coordinate y1 of the point where a line segment approximated by a broken line from the unit pixel is emitted from α.

(Equation 10)
A = α− (D2 × x1 + (1.0−D1) × (α−y3)) / 2

  In this way, by calculating the area of the font area surrounded by the corner portion with respect to one long side or one short side of the four sides of the unit pixel, the calculated area is divided based on the area ratio by α. The gray density within the unit pixel can be determined. Therefore, when the area occupied by the font display portion in the unit pixel is calculated, the CPU 11 performs a fill process on the pixel with the gray density equal to the calculated area ratio of the unit pixel constituting the corner portion. Then, the generated character image is displayed and output to the display means 17 or printed to the printing means 18 (step S209).

  The CPU 11 obtains an x coordinate value and ay coordinate value with a predetermined position as an origin for m unit pixels, and calculates a gray density for each unit pixel including a corner portion. The CPU 11 stores the area ratio of the font display portion as the gray density of the unit pixel in the gray density storage unit 122 of the storage unit 12 together with the coordinate position indicating the pixel position. FIG. 9 is an exemplary diagram of a data configuration stored in the gray density storage unit 122.

  For each font, the number of unit pixels nGray corresponding to the outline is set to 0 to m (m is a natural number), and x coordinates xGray (0) to xGray (m), y coordinates yGray (0) to yGray (m) and gray density shadeGray (0) to shadeGray (m) are stored. For a predetermined unit pixel, the gray density of the unit pixel is calculated by the above-described method, stored in the storage unit 12, and then moved to the next unit pixel. The gray density of the unit pixel is calculated by the above-described method, Store in the storage means 12. Such a process is repeated until the number of unit pixels nGray = 'm', and the gray density is calculated for all unit pixels constituting the contour.

  As described above, the area of the font display portion including the corner portion is calculated in accordance with the region difference value ΔR, and the calculated area is stored as the gray density in the storage unit 12 as it is. The gray density can be determined without performing complicated arithmetic processing. The CPU 11 can perform smooth display output or print output by painting the unit pixel including the corner portion with the gray density stored in the storage unit 12.

  As described above, according to the first embodiment, when a corner portion composed of a line segment approximated by a polygonal line exists in a unit pixel, the area is determined by relative coordinates according to which side intersects the vertical and horizontal sides. It is possible to reduce the calculation processing load related to area calculation for specifying the gray density of the unit pixel, and it is possible to shorten the time until the font is displayed or printed.

(Embodiment 2)
Hereinafter, an outline font output apparatus according to Embodiment 2 of the present invention will be specifically described with reference to the drawings. Since the configuration of the outline font output device 10 according to the second embodiment is the same as that of the first embodiment, detailed description thereof will be omitted by attaching the same reference numerals.

  FIG. 10 is a flowchart showing a processing procedure of the CPU 11 of the outline font output apparatus 10 according to the second embodiment of the present invention. The CPU 11 of the outline font output device 10 reads the font data stored in the font data storage unit 121 of the storage unit 12 or the ROM 13 (step S1001), extracts the character code of the character to be displayed or printed from the ROM 13, Outline data that constitutes the contour is calculated (step S1002).

  The CPU 11 approximates the calculated outline data as a polyline as a set of short line segments (step S1003), and specifies the coordinates of pixels constituting the corner portion of the outline font (step S1004). The pixels constituting the corner portion are unit pixels composed of squares each having 8 bits (256 dots × 256 dots), and the following calculation is performed with one side as a unit length, for example, “1”.

  FIG. 11 is a diagram illustrating a process for approximating outline data to a polygonal line. In the second embodiment, the pixel coordinates of the contour are specified by using unit pixels formed by a square of 256 bits (dots) × 256 (dots) and 8 bits per side. Then, the following calculation is executed with the length of one side of the unit pixel as the unit length ‘1’. As shown in FIG. 11, a specific unit pixel is set as a starting point “0”, unit pixels including an outline are sequentially specified clockwise, and the coordinates of the unit pixel are set up to an end point “m” (m is a natural number) of a closed curve indicating the outline. Identify.

  CPU11 calculates the area of a font display part about the unit pixel in which the corner | angular part of a font display part is contained. FIG. 12 is an exemplary diagram of a unit pixel that is a target for calculating the area of the font display portion. The vertex at the lower left of the unit pixel is the origin (0, 0), and the length of one side is 1.0. As shown in FIG. 12, when a corner portion is included in a unit pixel, a point (xk, yk) in the unit pixel and points before and after passing through the unit pixel (xp, yp), (xq, yq) Thus, the area of the font display portion in the unit pixel can be obtained.

  The CPU 11 first obtains the coordinates of the point where the line segment approximated by each broken line and the side of the unit pixel intersect. In FIGS. 13A to 13D, a line segment approximated by a polygonal line and a side of the unit pixel intersect when exiting from the point (xk, yk) in the unit pixel toward the external point (xq, yq). It is a figure which shows the coordinate of the point to do. In FIG. 13, regions 1 to 4 are classified based on which side of the unit pixel intersects the line segment approximated by the broken line. FIG. 13A is an exemplary diagram in the case of the region 1, and the point where the outline font intersects is (1, yf).

  FIG. 13B is an exemplary diagram in the case of the region 2, and the intersecting point is (1-xf, 1). Xf is the decimal part of the x coordinate of the intersecting point. FIG. 13C is an exemplary diagram in the case of the region 3, and the intersecting point is (0, 1-yf). FIG. 13D is an exemplary diagram in the case of the region 4, and the intersecting point is (xf, 0). In FIG. 13, the line segment approximated by a broken line and the side of the unit pixel intersect when the light is emitted from the vertex (xk, yk) constituting the corner portion in the unit pixel toward the external point (xq, yq). Although the coordinates of the point to be described are explained, a line segment and unit pixel approximated by a polygonal line when incident from an external point (xp, yp) toward a vertex (xk, yk) constituting a corner portion in the unit pixel Region classification can also be performed in the same manner for the coordinates of the point where the side of the line intersects.

  After performing the region classification, the CPU 11 calculates the area of the part surrounded by one or more sides facing the vertex (xk, yk) constituting the corner part in the unit pixel (step S1005), and the unit pixel. The gray density for each is calculated (step S1006).

  Specifically, by executing the processing shown in FIG. 14, the area of the part surrounded by one or more sides facing the vertex (xk, yk) constituting the corner part in the unit pixel is calculated. The CPU 11 calculates a difference between a region where a line segment approximated to a polygonal line enters a unit pixel and a region where a line segment approximated to a polygonal line exits from the unit pixel, and sandwiches the vertices (xk, yk) constituting the corner portion 2 Specify which side of a unit pixel a line segment passes through. 14A to 14E show the font display portion according to the difference value ΔR between the region where the line segment approximated to the unit pixel is incident on the unit pixel and the region where the line segment approximated to the unit pixel is emitted from the unit pixel. It is a figure which shows the method of calculating | requiring an area.

  FIG. 14A shows a case where the difference value ΔR is “0”, and a line segment approximating the polygonal line is emitted from the unit pixel from the x coordinate x1 of the point where the line segment approximating the polygonal line enters the unit pixel. It is a figure which shows the method of calculating | requiring the area of the font display part when the x coordinate x2 of a point is larger. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (hatched portion) is calculated by (Equation 11).

(Equation 11)
A = D2 × (x2−x1) / 2

  FIG. 14B shows a case where the difference value ΔR is “0”, and a line segment approximating the polygonal line is emitted from the unit pixel from the x coordinate x1 of the point where the line segment approximating the polygonal line enters the unit pixel. It is a figure which shows the method of calculating | requiring the area of the font display part when the x coordinate x2 of a point is smaller. Since the right side of the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 12).

(Equation 12)
A = 1.0−D2 × (x2−x1) / 2

  FIG. 14C is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “1”. Since the right side in the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 13).

(Equation 13)
A = (D2 × (1.0−x1) + D1 × y1) / 2

  FIG. 14D is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “2”. Since the right side in the traveling direction of the broken line is displayed in gray, the area A of the font display portion (hatched portion) is calculated by (Equation 14). Note that x3 is a value obtained by subtracting x coordinate x2 of a point where a line segment approximated by a broken line from a unit pixel is emitted from 1.0.

(Equation 14)
A = ((D2 × (1.0−x1) + D1 + (1.0−D2) × x3)) / 2

  FIG. 14E is a diagram showing a method for obtaining the area of the font display portion when the difference value ΔR is “3”. Since the right side in the traveling direction of the broken line is displayed in gray, the area A of the font display portion (shaded portion) is calculated by (Equation 15). Note that y3 is a value obtained by subtracting from 1.0 the y coordinate y1 of the point where a line segment approximating a polygonal line from the unit pixel is emitted.

(Equation 15)
A = 1.0− (D2 × x1 + (1.0−D1) × (1.0−y3)) / 2

  As described above, by calculating the area of the font region surrounded by the corner portion with respect to one of the four sides of the unit pixel, the gray density in the unit pixel can be determined directly from the calculated area. Therefore, when the area occupied by the font display portion in the unit pixel is calculated, the CPU 11 performs a filling process on the unit pixel constituting the corner portion with a gray density equal to the calculated area (step In step S1007), the generated character image is displayed on the display unit 17 or printed on the printing unit 18 (step S1008).

  As described above, the area of the font display portion including the corner portion is calculated in accordance with the region difference value ΔR, and the calculated area is stored as the gray density in the storage unit 12 as it is. The gray density can be determined without performing complicated arithmetic processing. The CPU 11 can perform smooth display output or print output by painting the unit pixel including the corner portion with the gray density stored in the storage unit 12.

  As described above, according to the second embodiment, when a corner portion constituted by a line segment approximated by a polygonal line exists in a unit pixel, the area can be calculated with relative coordinates based on one side of the unit pixel. Thus, it is possible to reduce the processing load related to area calculation for specifying the gray density of the unit pixel, and it is possible to shorten the time until the font is displayed or printed.

It is a block diagram which shows the structure of the outline font output device which concerns on Embodiment 1 of this invention. It is a flowchart which shows the process sequence of CPU of the outline font output device which concerns on Embodiment 1 of this invention. It is an illustration figure of the process which approximates outline data to a broken line. It is an illustration figure of the unit pixel used as the object which calculates | requires the area of a font display part. It is a figure which shows the coordinate of the point where the line segment approximated by the broken line at the time of radiate | emitting toward the external point from the point in a unit pixel when the long side of a unit pixel is horizontal, and the side of a unit pixel intersect. It is a figure which shows the coordinate of the point where the line segment approximated to the broken line at the time of radiate | emitting toward the external point from the point in a unit pixel when the long side of a unit pixel is vertical, and the side of a unit pixel intersect. Font display according to the difference between the incident region and the region where the line segment approximated from the unit pixel exits when the region where the line segment approximated to the unit pixel is incident on the long side of the rectangle It is a figure which shows the method of calculating | requiring the area of a part. Font display according to the difference between the incident region and the region where the line segment approximated from the unit pixel exits when the region where the line segment approximated to the unit pixel is incident on the short side of the rectangle It is a figure which shows the method of calculating | requiring the area of a part. It is an illustration figure of the data structure memorize | stored in a gray density memory | storage part. It is a flowchart which shows the process sequence of CPU of the outline font output apparatus which concerns on Embodiment 2 of this invention. It is an illustration figure of the process which approximates outline data to a broken line. It is an illustration figure of the unit pixel used as the object which calculates the area of a font display part. It is a figure which shows the coordinate of the point where the line segment approximated to the broken line at the time of radiate | emitting toward the external point from the point in a unit pixel, and the side of a unit pixel cross. It is a figure which shows the method of calculating | requiring the area of a font display part according to the difference value of the region in which the line segment approximated to the unit pixel injects into the unit pixel, and the region in which the line segment approximated to the unit line from the unit pixel emits.

Explanation of symbols

10 Outline font output device 11 CPU
12 recording means 13 ROM
14 RAM
15 Auxiliary storage means 16 Input means 17 Display means 18 Printing means 121 Font data storage section 122 Gray density storage section

Claims (6)

The area occupied by the portion of the font area inside the polygonal line within the predetermined unit area including the pixel, with a polygonal line approximation of the closed curve indicating the outline of the outline font, and the gray density of the pixel where the corner portion of the approximate polygonal line exists Is an outline font output device that outputs an outline font.
The unit area is rectangular.
Means for determining whether one side of the unit region intersecting the approximate polygonal line is a long side or a short side of the unit region;
Means for identifying the distance from the long side or short side to the corner and the distance from the other side to the intersection on the long side or short side;
Based on the specified distance, and means that to calculate one or area of the font area, which is surrounded by a plurality of sides and the fold line of the unit areas facing the corner portions of the polygonal line approximating in the unit area,
Means for determining a ratio of the calculated area to the area of the unit region as the ratio;
Features and to luer out line font output device that comprises a. The area occupied by the portion of the font area inside the polygonal line within the predetermined unit area including the pixel, with a polygonal line approximation of the closed curve indicating the outline of the outline font, and the gray density of the pixel where the corner portion of the approximate polygonal line exists Is an outline font output device that outputs an outline font.
The unit area is square;
Means for identifying a distance from one side of the unit region that intersects with the approximate polygonal line, and a distance from the other side of the intersection on the one side;
Means that to calculate the area of the font area based on the specified distance,
Means for determining a ratio of the calculated area to the area of the unit region as the ratio;
Features and to luer out line font output device that comprises a. The area occupied by the portion of the font area inside the polygonal line within the predetermined unit area including the pixel, with a polygonal line approximation of the closed curve indicating the outline of the outline font, and the gray density of the pixel where the corner portion of the approximate polygonal line exists Is an outline font output method that outputs an outline font.
The unit area is rectangular.
Determining whether one side of the unit region intersecting the approximate polygonal line is a long side or a short side of the unit region;
Identify the distance from the long side or short side to the corner and the distance from the other side to the intersection on the long side or short side,
Based on the identified distance, calculate the area of the font region surrounded by one or more sides and the polygonal line facing the corner portion of the approximate polygonal line in the unit region and sandwiching the font region ,
Features and to luer out line font output method that determining the ratio of the area calculated for the area of the unit area as the percentage. The area occupied by the portion of the font area inside the polygonal line within the predetermined unit area including the pixel, with a polygonal line approximation of the closed curve indicating the outline of the outline font, and the gray density of the pixel where the corner portion of the approximate polygonal line exists Is an outline font output method that outputs an outline font.
The unit area is square;
Identify the distance from one side of the unit region intersecting the approximate polygonal line, and the distance from the other side of the intersection on the one side ,
Calculate the area of the font area based on the specified distance ,
Features and to luer out line font output method that determining the ratio of the area calculated for the area of the unit area as the percentage. A closed curve indicating the outline of the outline font that passes through the rectangular unit region is approximated by a polygonal line, and the gray density of the pixel where the corner portion of the approximate polygonal line exists is expressed inside the polygonal line within the predetermined unit region including the pixel. A computer program that can be executed by a computer that outputs an outline font by specifying a ratio of an area occupied by a portion of a font area,
The computer,
Means for determining whether one side of the unit region intersecting the approximate polygonal line is a long side or a short side of the unit region;
It means for identifying a distance from the other side to the distance and the long side or intersection on the short side to the corner portions of the long or short side,
Based on the distance was especially boss, it means to calculate the area of the font area, which is surrounded by one or more sides and polygonal line of the unit region opposed sandwiching the corner portion and the font region of the polygonal line approximating in the unit area ,
Means for determining the ratio of the calculated area to the area of the unit region as the ratio; and
Features and to Turkey computer programs that function as the concentration specifying means for specifying the gray levels of pixels based on the ratio obtained. A closed curve indicating the outline of the outline font that passes through the square unit area is approximated by a polygonal line, and the gray density of the pixel where the corner portion of the approximate polygonal line exists is expressed inside the polygonal line within the predetermined unit area including the pixel. A computer program that can be executed by a computer that outputs an outline font by specifying a ratio of an area occupied by a portion of a font area,
The computer,
Means for identifying a distance from one side of the unit region intersecting the approximate polygonal line to the corner portion, and a distance from the other side of the intersection on the one side;
Means for calculating the area of the font region based on the identified distance ;
Means for determining the ratio of the calculated area to the area of the unit region as the ratio; and
Features and to Turkey computer programs that function as the concentration specifying means for specifying the gray levels of pixels based on the ratio obtained.

Images