JPH0573693A - Outline paint out system - Google Patents

Abstract

PURPOSE:To easily turn the system into hardware and to attain high speed paint out whose processing time is short. CONSTITUTION:All the scanning lines in an image generation area 10 are equally divided into the sections of respective natural number (n) dots. When a discrimination point to start inverting a picture element is extracted from the change of an outline at the time of generating the outline, the picture element of the discrimination point and scceeding picture elements are inverted only in the section of (n) dots to which the discrimination point on each scanning line belongs. After finishing the outline generation, the whole image generation area 10 is scanned and the picture elements are inverted when a last picture element in a leading section is inverted at each divided section of (n) dots to paint-out the inside of the outline.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contour filling method used for drawing graphics, generating patterns, and the like, and performing processing for generating an image in which the inside or outside of an object is filled from the contour of the object.

In recent years, due to the spread of DTP (desktop publishing) and the like, which make it possible to obtain beautiful documents easily on a desk, and the accompanying improvement in the resolution of output devices such as printers and displays, high-speed painting has become an essential technique.

[0003]

2. Description of the Related Art Various types of filling methods have been devised, but conventionally, in many cases, the filling is not performed by a dedicated filling device but is implemented by software.

Scan line conversion is a filling method that has been used in many systems. In this method, all contour lines are sorted in advance, a list is created, and the inside / outside of the figure is determined in order from the beginning of the created sort list to fill it, so that an area for creating the sort list is required. The area assigned to this sort list is determined by the number of constituent elements of the contour line, and if the contour line is infinite, an infinite area is required, which is not suitable for hardware implementation.

An EVEN / ODD rule can be given as a filling method suitable for hardware implementation. According to this method, a high-speed filling device can be easily configured without being affected by the number of contour constituent elements.

[0006]

[Problems to be Solved by the Invention] Conventional EVEN / OD
With the filling using D, a figure having a width of 1 dot cannot be expressed in the direction of the scanning line, and therefore it is necessary to overwrite the contour line on the filled image. In order to deal with this, it is necessary to provide an area for storing the contour line in addition to the image generation area, or to execute the contour drawing again after completing the filling. In addition, in the filling circuit using the EVEN / ODD rule, whether the inside of the object is sequentially scanned while scanning from the first pixel to the last pixel of the processing unit area,
Since the pixel is set while judging whether it is outside, there is a problem that it takes time to execute the filling in the processing unit area.

The present invention has been made in view of the above points, and an object of the present invention is to provide a contour filling method which can be easily implemented in hardware, has a short processing time, and can perform high-speed filling.

[0008]

1 (A) and 1 (B) show the principle of the present invention.

In FIG. 1A, the contour line generating means 11
Generates a contour line pixel by pixel based on the contour information.

The inverted pixel instructing means 12 extracts a discrimination point from the generated change in the contour line, selects an n-dot section to which the discrimination point belongs from the image generation area 10, and selects the i-th section of the selected n-dot section. When there is a discrimination point at, the inversion of the (n−i + 1) pixels after the i-th pixel is instructed.

The first pixel inversion means 13 inverts the n-dot section selected from the image generation area 10 based on the inversion instruction of the inversion pixel instructing means 12 when the contour line is generated.

After the contour generation is completed, the pixel inversion information holding means 14 holds the last pixel in a certain n dot section obtained by scanning the image generation area 10 as pixel inversion information in the next n dot section.

The second pixel inversion means 15 inverts the n-dot section based on the pixel inversion information held by the pixel inversion information holding means 14 obtained by scanning the image generation area 10 after the contour generation is completed.

In FIG. 1B, the third pixel inversion means 16 is held in the pixel inversion information holding means 14 after the contour generation is completed based on the inversion instruction of the inversion pixel instruction means 12 at the time of generating the contour line. The n-dot section of the pixel generation area 10 is inverted based on the pixel inversion information.

[0015]

According to the present invention, since the contour is generated and the pixel is inverted while scanning the contour, the storage capacity is small and the hardware can be easily realized.
Further, since each scanning line in the image generation area is divided into n-dot sections and filling is performed in each n-dot section unit, unnecessary filling is not repeated and the time required for filling is short.

[0016]

2 is a block diagram of an embodiment of the present invention.

In this embodiment, the image generation area is 32 ×
A 32 dot memory is used. Further, the processing unit is 8 bits (8 pixels), and 32 dots in the horizontal direction of the image generation area are divided into 8 dots for processing.

In FIG. 2, reference numeral 31 denotes a contour generation unit for generating a contour from the input contour information, and the contour is generated by using a DDA (digital differential analyzer) or the like.
The discrimination point extracting unit 32 extracts discrimination points from the generated contour. The mask pattern generation unit 33 generates a mask pattern indicating an inversion pixel from the extracted discrimination points. 34
Is an inversion processing unit that inverts pixels. Reference numeral 35 generates a scan address when scanning the image generation area. An image memory 36 serves as an image generation area. A selector 37 selects an address of the image memory.

The operation of the embodiment will be described below.

When the contour information (vertex coordinates of the contour) is input, the contour generator 31 performs linear interpolation by the DDA to generate the contour pixel by pixel. At this time, the generated contour data is the coordinate value (X, Y) of the contour.

Reference numeral 32 extracts a discrimination point from the generated contour.

The applicant of the present invention has previously proposed a method of determining the discrimination points from the contour points and filling the inside of the contours by software processing for filling the spaces between the discrimination points in Japanese Patent Laid-Open No. 63-305478.
When this outline is described with reference to FIG. 3, (a) shows an original figure, and when the contour of this original figure is extracted, it becomes (b) in the figure. The respective pixels (dots) of the contour figure are traced counterclockwise as shown in FIG. 6C, and dots are generated / erased by a predetermined logic to obtain FIG. The dots indicated by double circles in this figure are called discrimination points here, and there are only two dots in the horizontal direction (scanning direction during filling).

The table below shows the set capacities of discrimination points. In this table, the discrimination point is not set for the pixel, is the discrimination point is set for the pixel, is the discrimination point is set on the right side of the pixel, is the discrimination point for both the pixel and the right side of the pixel. To set.

[0024]

[Table 1]

The moving method from the pixel immediately before the reference pixel is the preceding moving direction, and the moving direction to the pixel after the reference pixel is the following moving direction. The intersection is the process of determining the direction and setting the discrimination point for the referenced pixel. There are four types of processing, i.e., determination points j ₁ , j ₁₁ ,
...... is set according to the rules in this table.

In FIG. 3D, as scanning and television scanning (from left to right, from top to bottom), filling is started at the first discrimination point (filling at the first discrimination point), and painting is completed at the next discrimination point. (The next discrimination point is not filled, and the filling is performed up to the previous one), the original figure of FIG. 3A is obtained.

When the discrimination points are extracted, the discrimination point extraction unit 32
Generates an address for selecting the processing unit (word) to which this discrimination point belongs from the image memory. The coordinate value (X, Y) of the discrimination point is represented by 5 bits, and the Y coordinate is the upper 5 bits and the upper 2 bits of the X coordinate are the lower 2 bits. 37.

For example, the coordinate value of the discrimination point: (14, 20)
Then, the Y coordinate and the X coordinate are “10100” and “01110”, so the address is 1010001. When the address is determined, the content (word to which the discrimination point belongs) of the corresponding image memory 36 is read.

The address input to the image memory 36 is
The address generated by 32 and 35 in the selector S1
One of the addresses generated by is selected and used. In this selection, if the contour line is being generated, the address indicated by the discrimination point extracting unit 32 is selected, and if the contour is not being generated, the address indicated by the scanning address generating unit 35 is selected.

Also, the X of the discrimination point obtained by the discrimination point extraction unit 32
The lower 3 bits of the coordinates are passed to the mask pattern generator 33. The mask pattern generation unit 33 uses the PLA to indicate the inversion pixel based on the received value. A mask pattern is generated and passed to the inversion processing section 24. The mask pattern generation rule is as shown in FIG. In FIG. 4, black circles represent pixels that are inverted with a value of “1”, and white circles represent pixels that are not inverted with a value of “0”.

The image information 34 read from the image memory 36 is fetched, and the pixels designated by the mask pattern are inverted. The inversion processing unit 34 has a configuration as shown in FIGS.

FIG. 5 shows that contour drawing is being executed (DRAWING).
It is the first pixel inversion circuit used inside. The first pixel inversion circuit is an exclusive OR circuit (XOR) 40.
_{1 to} 40 to _n are assigned to each bit (pixel), and the mask pattern generated according to the discrimination point extracted from the change in the contour as the inversion instruction for each pixel is XO.
The pixel information read from the image memory 36 input to the R40 ₁ to 40 _n also corresponds to the XOR 40 ₁ to 4 respectively.
0 _n is input, and the pixel inversion is executed by taking the exclusive OR of the inversion instruction and the information of each pixel.

FIG. 6 shows a second pixel inversion circuit used when contour extraction is not performed, that is, during inversion processing. In the second pixel inversion circuit, XOR 42 _{1 to} 42 _n are assigned to each bit (pixel), and the pixel information of the front pixel is held as an inversion instruction for each pixel. The output of the latch circuit 43 is input to XOR. The XOR 42 that also corresponds to the pixel information read from the image memory 36
_{1 to} 42 _n are input, and the pixel is inverted by taking the exclusive OR with the inversion instruction. Further, the latch circuit 43 which holds the pixel inversion information holds the pixel information of the final pixel (the output of the XOR 42 _n on the LSB side).

Further, the inversion processing section 34 can also be constituted by a single third pixel inversion circuit as shown in FIG.

The pixel inversion circuit in this case has an XOR of 45.
It is assigned to each bit (pixel) of _{1 to} 45 _n , and holds the pixel information of the front pixel as the mask pattern generated by the mask pattern generator 33 by the selector 46 and the pixel inversion information as an inversion instruction for each pixel. is doing. The one selected from the outputs of the latch circuit 47 is input to the corresponding XOR 45 _{1 to} 45 _n . The selector 46 selects a mask pattern during contour drawing execution (DRAWING), and otherwise selects the output of the latch circuit 47 as an inversion instruction. The image information read from the image memory 36 also corresponds to the corresponding XORs 45 _{1 to} 45.
_It is input to _n , and the pixel is inverted by taking the exclusive OR with the inversion instruction. In addition, the pixel information (LSB) of the last pixel is stored in the latch circuit 47 that holds the pixel inversion information.
The output of the XOR45 _n on the side) is held.

FIGS. 8A, 8B, and 8C show a mask pattern, an image memory output, and an inverted pixel pattern, respectively, during execution of contour drawing.

Here, when the outline information of the image as shown by the black circles in FIG. 9 is given, the process proceeds clockwise starting from the point a and the discrimination points shown by the double circles in FIG. 10 are extracted. .. When contour generation proceeds from the starting point a to the point b
The state shown in 1 is obtained.

When the contour generation proceeds to the point b, FIG.
The discrimination point f in is extracted. The coordinate value of the discrimination point f is
Since it is (11, 6), the address (0011001) for selecting the word to which the discrimination point belongs is determined, and the discrimination point f
The content of the word including the is read from the image memory 36. The read image information is shown in FIG.

A mask pattern shown in FIG. 15B is generated by the lower 3 bits of the X coordinate. Inversion of the pixels indicated by the mask pattern is executed, and the image shown in FIG. 15C is written in the image memory 36 again.

Next, the processing when the contour line has been generated up to the coordinate c will be described.

When the contour generation proceeds to c, the discrimination point g in FIG. 11 is extracted. The coordinate value of the discrimination point g is
Since it is (14, 6), the address (0011001) for selecting the word to which the discrimination point belongs is determined. Since this is the same word as the word including the coordinate f, the image shown in FIG. 16A read from the image memory 36 is the same as the result shown in FIG. is there.

A mask pattern shown in FIG. 16B is generated by the lower 3 bits of the X coordinate. Inversion of the pixels indicated by the mask pattern is executed, and the image shown in FIG. 16C is written in the image memory 36 again.

After that, the image when the contour generation has proceeded to the point d is in the state shown in FIG. 12, and the image when the contour generation has proceeded to the point e is in the state shown in FIG. The image at is in the state shown in FIG.

After the contour line has been generated, the pixels read from the image memory 36 are inverted while scanning the entire image area. Since the contour drawing has been completed, the address shown by the scanning address generating unit 35 in FIG. 2 is used as the address for the image memory 36. Further, in the inversion processing unit 34, pixel inversion is performed by using the pixel inversion information held in the latch circuit 43 or 47 as an inversion instruction.

When processing the first word of one scan line, the pixel inversion information is initialized. In order to scan the image area, the scan address generator 35 sequentially generates addresses along the scan lines, and the read contents of the image memory 36 are inverted according to the pixel inversion information. I do. Here, the result of the inversion processing becomes the pixel information after the completion of the filling. The word for which the filling has been completed is written into the image memory 36 again, or is read from the outside as the output of the filling device.

When the processing of one word is completed, the pixel information of the final pixel (on the LSB side) of the completed word is held in the latch circuit 43 or 47 as new pixel inversion information. However, as described above, when processing the first word of the scanning line, it is necessary to initialize the latch circuit 43 or 47. By applying the above processing to the entire image area, a final image can be obtained.

The processing for the scanning line indicated by ZZ in FIG. 14 will be described below. (1) The latch circuit 43 is initialized to process the first word of the scanning line. (2) As shown in FIG. 17A, the scan address (0011
100) is generated and the content of the corresponding image memory 36 is read. (3) Inversion processing is performed according to the pixel inversion information. In this case, since the pixel inversion information has been initialized, not all pixels are inverted. (4) The pixel information “0” of the final pixel is latched in the latch circuit 43 as pixel inversion information. (5) As shown in FIG. 17B, the scan address (0011
101) is generated and the content of the corresponding image memory 36 is read. (6) Inversion processing is performed according to the pixel inversion information. In this case, since the pixel inversion information is "0", all pixels are not inverted. (7) The pixel information “0” of the final pixel is latched in the latch circuit 43 as pixel inversion information. (8) As shown in FIG. 17C, the scan address (0011
110) is generated and the content of the corresponding image memory 36 is read. (9) Inversion processing is performed according to the pixel inversion information. In this case, since the pixel inversion information is "0", all pixels are not inverted. (10) The pixel information “1” of the final pixel is latched in the latch circuit 43 as pixel inversion information. (11) As shown in FIG. 17D, the scan address (00
11111) is generated and the content of the corresponding image memory 36 is read. (12) Inversion processing is performed according to the pixel inversion information. In this case, since the pixel inversion information is "1", all pixels are inverted. (13) Since the processing for one scanning line is completed, the latch circuit 43 is initialized to perform the processing for the next scanning line.

By using the circuit configured as described above, it is possible to obtain an image in which the inside of the contour is filled. 18
It is a figure that has been filled.

As described above, since the contour is generated and the pixel is inverted while scanning the ring portion, the storage capacity is small and the hardware can be easily realized. Only the pixel inversion processing is required. Filling is feasible and effective in reducing the circuit scale. Further, since each scanning line in the image generation area is divided into n-dot sections and filling is performed in each n-dot section unit, like the conventional filling circuit, filling is performed while scanning from the first pixel to the last pixel in a word. Since it is not necessary to perform, it is possible to shorten the time required for filling without repeating unnecessary filling and realize high-speed processing.

Furthermore, by extracting the discrimination points, it is possible to express a figure having a width of 1 dot in the scanning direction, and it is not necessary to overwrite the contour of the filled image.

[0051]

As described above, according to the contour filling method of the present invention, the hardware can be easily implemented, the processing time is short, and high-speed filling is possible, which is extremely useful in practice.

[Brief description of drawings]

FIG. 1 is a principle diagram of the present invention.

FIG. 2 is a block diagram of an embodiment of the method of the present invention.

FIG. 3 is a diagram for explaining discrimination points.

FIG. 4 is a diagram showing a mask pattern generation rule.

FIG. 5 is a configuration diagram of a first inversion processing unit.

FIG. 6 is a configuration diagram of a second inversion processing unit.

FIG. 7 is a configuration diagram of a modification of the inversion processing unit.

FIG. 8 is a diagram for explaining pixel inversion.

FIG. 9 is a diagram showing a contour line.

FIG. 10 is a diagram showing discrimination points.

FIG. 11 is a diagram for explaining the method of the present invention.

FIG. 12 is a diagram for explaining the system of the present invention.

FIG. 13 is a diagram for explaining the system of the present invention.

FIG. 14 is a diagram for explaining the system of the present invention.

FIG. 15 is a diagram showing an inversion process when a discrimination point f is extracted.

FIG. 16 is a diagram showing an inversion process when a discrimination point g is extracted.

FIG. 17 is a diagram for explaining image area scanning.

FIG. 18 is a diagram showing a filled image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 image generation area 11 contour line generation means 12 inversion pixel instruction means 13 first pixel inversion means 14 pixel inversion information holding means 15 second pixel inversion means 16 third pixel inversion means

Claims (3)

[Claims] 1. A contour filling method for filling the inside of a contour line drawn in an image generation area based on contour information, wherein all scanning lines in the image generation area are divided into intervals of natural number n dots. When dividing and extracting a discrimination point at which pixel inversion starts from contour change during contour generation, the pixels after the discrimination point are inverted only in the n dot section to which the discrimination point belongs on each scanning line, and contour generation is performed. After the end, the entire image generation region is scanned, and when the last pixel of the preceding section is reversed for each section of the divided n dots, it is reversed to fill the inside of the contour. Contour filling method. 2. The contour filling method according to claim 1, wherein a contour line generating means (11) for generating a contour line pixel by pixel based on contour information, and a discrimination point is extracted from a change in the generated contour line. , The n-dot section to which the discrimination point belongs is selected from the image generation area (10), and when the i-th discrimination point of the selected n-dot section is present, the i-th and subsequent (n−i +)
1) Inverted pixel instructing means (1 for instructing inversion of one pixel
2), a first pixel reversing means (13) for reversing a section of n dots selected from the image generation area (10) based on the reversing instruction of the reversing pixel instructing means at the time of contour generation, and after the contour generation is completed. , A certain n obtained by scanning the image generation area
Pixel inversion information holding means (14) for holding the last pixel in the dot section as pixel inversion information in the next n dot section
And a second pixel for inverting the n-dot section based on the pixel inversion information obtained from the last pixel of the previous section by scanning the image generation area after the contour generation is completed. The contour filling method according to claim 1, further comprising reversing means (15). 3. The contour filling method according to claim 1, wherein a contour line generating means (11) for generating a contour line pixel by pixel based on contour information, and a discrimination point is extracted from a change in the generated contour line. , The n-dot section to which the discrimination point belongs is selected from the image generation area (10), and when the i-th discrimination point of the selected n-dot section is, the (n-i + 1) th pixel of the i-th and subsequent pixels is selected. An inversion pixel instruction means (12) for instructing inversion, and a certain n obtained by scanning the image generation area after the contour generation is completed.
Pixel inversion information holding means (14) for holding the last pixel in the dot section as pixel inversion information in the next n dot section
And a step of inverting the n-dot section of the pixel generation area based on the inversion instruction of the inversion pixel instruction means at the time of generating the contour line, and based on the pixel inversion information held by the pixel inversion information holding means after the end of the outline generation. 3. The contour filling method according to claim 1, further comprising three pixel inversion means (16).