JPH11288261A - Method and device for picture processing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for picture processing which doesn't require fill up of breaks by preventing breaks from occurring at contacts of contours when fringing the contours with a certain width to decorate characters. SOLUTION: A contour generation means 2 substitutes each stroke of contour information with a closed curve pattern free from breaks, and a picture generation means 4 generates new contour information to decorate characters by painting-out. Thus, the capacity of a memory to be used is made relatively small, and only two closed curves overlap, and painting-out processing is quickly performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing method and apparatus, and more particularly, to image processing for storing character design information as outline information and expressing and outputting characters with a line having a constant width based on the outline information. Method and apparatus.

[0002]

2. Description of the Related Art In an output device based on a bitmap screen such as a page printer or a display, as pixels become finer, that is, as the resolution becomes higher, a large amount of data is required to display characters and graphics of the same size. Required. In particular, even for character information having a fixed contour, it is necessary to have bitmap data for each size, which is inefficient. Therefore, character information does not have bitmap data for each size but outline information. A method of displaying a character by enlarging or reducing and then filling the inside of the outline of the character is advantageous.

FIG. 9 shows an outline of a character and a bit map obtained from the outline. When a character is output (displayed) as shown in the figure, a bitmap is output in which pixels inside the outline of the character to be output are inverted with respect to other pixels. The pixel to be inverted is determined to be a pixel inside the contour line when the center point of the pixel is inside the contour line as shown in FIG. 10, and is determined by this determination.

The outline (outline) is shown in FIG.
As shown in (1), it is represented by a stroke having a length and a direction, and by changing the length, a character to be output can be enlarged or reduced.

Incidentally, as one of the character modification methods in a word processor or the like, there is a method of bordering a contour line with a constant width as shown in FIG. The easiest means for realizing this modification method is to prepare outline information having a line width as shown in FIG. 13, but in addition to the original (having no line width) outline information, another Therefore, the amount of information to be held increases. Further, in the case of performing character modification using such contour information, restrictions are increased such that characters can be modified only with the line width of the prepared contour information.

For this reason, a method of performing a modification such that a contour is bordered with a constant width generally uses a means of creating new contour information using the original contour information. For example, to create a contour as shown in FIG. 13, new contours 52 and 53 are created from the original contour 51 as shown in FIG.

As described above, when a character having a line width is output, as shown in FIG.
5, bitmaps 56 and 57 each having a fixed width
And synthesize them. However, if the rectangular bitmaps 56 and 57 are simply combined as shown in the figure, a cutout will occur on the side where the two bitmaps are connected to each other and open more than 180 degrees. Therefore, a rectangle 58 formed by an extension of the contour shown in FIG. 16A and an arc 59 centered on the connection point of the contour shown in FIG. Connect smoothly. However, such processing is performed as shown in FIG.
It is necessary to create bitmap patterns 56, 57, and 58 separately and then combine them by logical addition, and also to calculate the size of the rectangle and the angle of the arc to be added to the notch. This is significantly different from the procedure for generating a normal character pattern.

On the other hand, in the graphic processing apparatus disclosed in Japanese Patent No. 2621633, a standard graphic is prepared in advance, and processing for synthesizing the standard graphic with the cutout portion is performed. For example, if a circular bitmap pattern prepared as a standard figure is synthesized, the synthesis result is the same as the case where the arc 59 shown in FIG. 16B is added. Unlike this case, the angle (of the arc) does not need to be calculated, and processing can be performed at high speed.

[0009]

As described above, in the conventional image processing apparatus, a plurality of bitmap patterns are created and synthesized to realize character modification for bordering a contour line at a fixed width. I have. This is significantly different from the procedure for filling the original outline (the procedure for outputting normal characters), so many new functions must be added to achieve such character modification. Becomes
Further, a memory (a work area of a bitmap or the like) for the added function is required, so that the memory efficiency is deteriorated. Such a point also occurs in the above-described Japanese Patent No. 2621633 in the graphic processing apparatus.

Therefore, the present invention provides an image processing method and apparatus which do not cause a cutout at a contact point of a contour line and do not need to fill the cutout when performing character modification for bordering a contour line with a constant width. The purpose is to provide.

[0011]

According to the first aspect of the present invention, there is provided an image processing method for modifying a character by changing an outline of a character to be drawn to an outline having an arbitrarily set width. In, the outline of the character to be drawn is approximated by a plurality of straight lines, each of the approximated outlines is replaced with a closed curve in which one side of a rectangle is replaced with a semicircle, and an area inside the closed curve is filled. The character modification is performed.

According to a second aspect of the present invention, in the first aspect of the present invention, the closed curve is such that the center of the semicircle coincides with the first end point of the approximated contour line, and The midpoint of the opposite side and the second end point of the approximated contour line coincide with each other.

According to a third aspect of the present invention, in the first aspect of the present invention, the closed curve indicates that the diameter of the semicircle and the length of the side facing the semicircle are equal to the arbitrarily set width. Features.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the closed curve has a direction clockwise or counterclockwise of the closed curve, and the filling is performed according to a non-zero winding rule. I do.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, the direction of the closed curve is unified for all closed curves forming the character.

According to a sixth aspect of the present invention, in the image processing apparatus for modifying a character by changing the outline of a character to be drawn to an outline having an arbitrarily set width, the outline of the character to be drawn may be a plurality of straight lines. Coordinate conversion means that approximates the following, a closed curve in which one side of a square is replaced with a semicircle, and a contour line creation means that replaces the closed curve with a contour line approximated by the coordinate conversion means; and the contour line creation means Image generating means for filling an area inside the exchanged closed curve.

According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the contour line creating means includes a contour line having a distance between a center of the semicircle and a midpoint of a side facing the semicircle. A closed curve equal to the length of the line is created, and the center of the semicircle coincides with the first end point of the approximated contour line, and the midpoint of the side facing the semicircle and the approximated contour line The approximated contour line and the closed curve are exchanged so that the position coincides with the second end point.

In the invention according to claim 8, in the invention according to claim 6, the contour line creating means is configured so that the diameter of the semicircle and the length of the side facing the semicircle are equal to the arbitrarily set width. It is characterized in that the closed curves are created so as to be equal.

According to a ninth aspect of the present invention, in the sixth aspect of the present invention, the closed curve has a direction clockwise or counterclockwise of the closed curve, and the image generating means performs the non-zero winding rule on the closed curve. It is characterized in that the area inside is filled.

According to a tenth aspect of the present invention, in the ninth aspect of the invention, the direction of the closed curve is unified for all closed curves forming the character.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an image processing method and apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram showing the configuration of an image processing apparatus according to the present invention. The image processing apparatus 10 performs coordinate conversion such as enlargement / reduction of outline information, division of a curve (contour line information) into straight lines of a size that can be seen smoothly in accordance with pixels (approximation using a plurality of straight lines), and modification of contour lines. When performing, the coordinate transformation means 1 for setting the line width and a closed curve including each stroke constituting the outline information are generated. When the closed curves are generated for all the strokes, these are set as new outlines as the original outline. Contour creating means 2 for replacing a contour, semicircle calculating means 3 for calculating and generating a contour of a semicircular portion of a closed curve containing a stroke from contour information included in contour creating means 2 and coordinate converting means 1 Alternatively, it is provided with an image generating means 4 for generating a bitmap from the contour information output from the contour creating means 2 by a filling method called non-zero winding.

As shown in FIG. 2, the image processing apparatus 10 actually includes a CPU 11, a RAM 12, a ROM 13, an external storage device 14, and a video I / F (interface) 1.
5, a frame buffer 16 and a printer I / F (interface) 17.

The coordinate transformation means 1, contour line creation means 2, semicircle calculation means 3, and image generation means 4 shown in FIG.
2 or a program stored in the ROM 13
It is configured on U11. The ROM 13 and the external storage device 14 store outline font data (outline information). The frame buffer 16 temporarily stores the bitmap image generated by the image generation unit 4 and stores the image in a display (not shown) connected to the video I / F 15 or a page printer (not shown) connected to the printer I / F 17. (Not shown) or the like.

Next, the operation of the image processing apparatus 10 will be described. In the image processing apparatus 10, when outputting a normal character, the image generation unit 4 generates a bitmap based on the outline information divided into straight lines by the coordinate conversion unit 1. It is the same as the method being done.

When outputting a character modified by bordering a contour, the image processing apparatus 10 outputs the contour information divided into straight lines by the coordinate converting means 1 to the contour forming means 2. The image generating means 4 generates a bitmap based on the closed curve, replacing the closed curve containing the information.

FIG. 3 shows a closed curve created by the contour line creating means 2. The contour line creating means 2 generates a closed curve composed of three straight lines 22, 23 and 24 and one semicircle 25 with respect to the stroke 21 of the (original) contour line as shown in FIG. . The closed curves are straight lines 22 and 23 which are parallel to and equal in length to the stroke 21 of the contour,
The stroke 21 is composed of a straight line (bottom side) 24 having the same length as the line width of the decoration character to be created by vertically touching the stroke 21 at its start point, and a semicircle 25 having the diameter of the line width of the decoration character centered on the end point of the stroke 21. You. Since this closed curve becomes a stroke of a new contour, it has a direction similar to the stroke 21 of the original contour, and the direction is unified so that all closed curves are clockwise (or counterclockwise). The unification of the directions is performed in order to fill the inside of the outline at the time of filling described later.

Assuming that such a closed curve is a stroke of a new contour, each stroke is connected at the center 26 of the semicircle (the end point of the original contour) as shown in FIG.
The base (starting point) of the connected stroke does not protrude from a semicircle having the same length of diameter, and the outermost shell of the closed curve is connected smoothly at any angle.

Next, the filling of a new contour line created by the closed curve created by the contour creating means 2 will be described. The contour line is filled by a widely used filling rule called non-zero winding in the image generation unit 4, and is divided into a contour line (modification character) created by the contour line creation unit 2 and a straight line by the coordinate conversion unit 1. The same method is applied to both of the contour lines (normal characters).

Here, the filling by non-zero winding will be described with reference to FIGS. In the non-zero winding rule filling, as shown in FIG. 4A, at the intersection of the contour and the scanning line, the contour having a direction moves the scanning line from right to left with respect to the scanning direction (from bottom to top in the drawing). Counts as +1 when piercing through, and −
Counting is performed as 1, and the area where the count value is other than 0 is painted out (left to right may be set to +1). Incidentally, the contour shown in FIG. 4A looks like a combination of a clockwise contour and a counterclockwise contour.
It is a combination of the strokes of a clockwise closed curve as shown in FIG. Also, the direction of the outline is shown in FIG.
In the case shown in (1), the non-zero winding rule may cause the portion outside the outline to be filled.

The properties of non-zero winding include:
Even if two outlines as shown in FIG. 5A are superimposed as shown in FIG. 5B, if the directions of the outlines are unified clockwise or counterclockwise, the overlapping area is Since it does not become 0, it is surely painted. Therefore, FIG.
As shown in (c), the area where the two strokes overlap is also reliably filled.

Next, the operation of the image processing apparatus 10 will be described with reference to FIG. FIG. 6 is a flowchart illustrating the flow of the operation of the image processing apparatus 10.

In the image processing apparatus 10, the CPU 11 reads image information and the like stored on a RAM (or RAM 12) not shown through an interface or the like not shown.
If the image information is a character code, outline information (outline font data) is read from the ROM 13 or the external storage device 14 and the execution of the image generation program is started (step 101).

When the execution of the image generation program is started, the coordinate conversion means 1 (by the CPU 11) converts the coordinates of the outline (outline) to a size desired to be output, and divides the outline into a plurality of short straight lines. (Step 10
2). Next, when modifying the outline (character) (YES in step 103), the coordinate conversion means 1 includes the outline creation means 2 (including the semicircle calculation means 3 and both CPU 11
(Step 10).
4).

Next, the outline creating means 2 reads each stroke of the outline (step 105), and sets the end point and direction of each stroke in the semicircle calculating means 3 (step 10).
6). The semicircle calculation means 3 calculates a semicircle portion of a new contour line from the set end point, direction, and line width of each stroke,
It is created (step 107). Subsequently, the contour creating means 2 creates contours surrounding three directions other than the semicircular portion of the new contour created by the semicircle calculating means 3 (step 108), and the newly created contour The information is replaced with the original contour information (step 109).

If the original outline information is replaced with the new outline information (step 109), or if the outline is not modified (NO in step 103), the image generating means 4 executes the processing based on the outline information. A bitmap is created by performing filling with a non-zero winding rule (step 110), and output to the frame buffer 16 (step 111).

Here, an output device (not shown) such as a display or a page printer is provided at a predetermined time interval or a
The image processing apparatus 10 checks the frame buffer 16 in response to the end signal from the CPU 11 and outputs the registered bitmap, thereby ending the operation of the image processing apparatus 10 (step 112).

In the above-described embodiment, the case where the contour is modified has been described as an example. However, the present invention can be used for generating an image of a stroke font having only the skeleton as information as shown in FIG. In this case, it is possible to generate an image as shown in FIG. 7B, but since the shapes of both ends 31 of the stroke need to be aligned, the stroke at the start end is changed as shown in FIG. 8A. (The two ends 31 have a semicircular shape), or the end stroke must be changed as shown in FIG. 8B (the two ends 31 have a linear shape).

[0039]

As described above, according to the present invention, each stroke of the outline information is replaced with a closed curve pattern that does not generate a notch, and new outline information is generated and filled. Since the character is configured to be modified, the capacity of the memory used can be made relatively small, and the overlap of the closed curves becomes only two closed curves.
The filling process can be performed at high speed.

Further, even for an image processing apparatus which does not have a character modification function, the portion for performing the filling process can be used. Therefore, the character modification function can be achieved simply by adding a function of replacing the outline stroke with a closed curve pattern. You can have.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to the present invention.

FIG. 2 is a diagram showing an actual configuration of the image processing apparatus 10.

FIG. 3 is a diagram showing a closed curve created by a contour creation unit 2;

FIG. 4 is a diagram (1) for explaining filling by non-zero winding;

FIG. 5 is a diagram (2) for explaining filling by non-zero winding;

FIG. 6 is a flowchart showing a flow of the operation of the image processing apparatus 10;

FIG. 7 is a diagram showing an example of a stroke font having only a skeleton as information.

FIG. 8 is a diagram showing shapes of strokes to be a start end and an end.

FIG. 9 is a diagram showing an outline of a character and a bitmap obtained from the outline.

FIG. 10 is a view for explaining filling inside the outline.

FIG. 11 is a view for explaining strokes constituting a contour line.

FIG. 12 is a diagram showing an example of character modification.

FIG. 13 is a view showing contour line information having a line width.

FIG. 14 is a diagram showing an example of creating a new contour from an original contour.

FIG. 15 is a diagram showing a specific example of creating a new contour from an original contour.

FIG. 16 is a diagram showing an example of connecting a notched portion with a new contour line.

FIG. 17 is a diagram showing each component of a bitmap pattern using a new contour line.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 coordinate conversion means 2 contour creation means 3 semicircle calculation means 4 image generation means 10 image processing device 11 CPU 12 RAM 13 ROM 14 external storage device 15 video I / F (interface) 16 frame buffer 17 printer I / F ( Interface) 21 Stroke 22, 23, 24 Straight line 25 Semicircle 26 Center of semicircle 31 Both ends of stroke

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI G09G 5/36 530 G06F 15/72 400

Claims (10)

[Claims] 1. An image processing method for modifying a character by changing an outline of a character to be drawn to an outline having an arbitrarily set width, wherein the outline of the character to be drawn is approximated by a plurality of straight lines. An image processing method, wherein each of the outlines is replaced with a closed curve in which one side of a rectangle is replaced by a semicircle, and the character modification is performed by filling an area inside the closed curve. 2. The closed curve, wherein the center of the semicircle coincides with a first end point of the approximated contour, and a midpoint of a side facing the semicircle and a second point of the approximated contour. 2. The image processing method according to claim 1, wherein the two end points coincide with each other. 3. The image processing method according to claim 1, wherein a diameter of the semicircle and a length of a side facing the semicircle are equal to the arbitrarily set width. 4. The image processing method according to claim 1, wherein the closed curve has a clockwise or counterclockwise direction with respect to the closed curve, and the filling is performed according to a non-zero winding rule. 5. The image processing method according to claim 4, wherein the direction of the closed curve is unified for all closed curves forming the character. 6. An image processing apparatus for modifying a character by changing an outline of a character to be drawn to an outline having an arbitrarily set width, wherein coordinate conversion means for approximating the outline of the character to be drawn with a plurality of straight lines. Creating a closed curve in which one side of a rectangle is replaced by a semicircle, and replacing the closed curve with a contour approximated by the coordinate conversion means; and an inside of the closed curve replaced by the contour creating means. An image processing apparatus comprising: an image generation unit that fills an area. 7. The contour creating means creates a closed curve in which the distance between the center of the semicircle and the midpoint of the side opposite to the semicircle is equal to the length of the approximated contour, The center and the first end point of the approximated contour line coincide with each other, and the midpoint of the side facing the semicircle coincides with the second end point of the approximated contour line. 7. The image processing apparatus according to claim 6, wherein the approximated contour and the closed curve are exchanged. 8. The contour line creating means creates the closed curve such that the diameter of the semicircle and the length of a side facing the semicircle are equal to the arbitrarily set width. The image processing device according to claim 6. 9. The closed curve has a direction clockwise or counterclockwise of the closed curve, and the image generating means fills an area inside the closed curve according to a non-zero winding rule. 7. The image processing device according to 6. 10. The image processing apparatus according to claim 9, wherein the direction of the closed curve is unified for all closed curves forming the character.