JP2000082150A - Image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To output information in a closed area by a simple processing and with a small information amounts. SOLUTION: This image processor is provided with a vector data generating part 81 for generating vector data indicating an outline from plotting data to be plotted, a scanning means 82 for scanning the vector data generated by the vector data generating part 81 for each line, a recognizing means 83 for recognizing the kind of the side of the vector data included in each line scanned by the scanning means 82, and an outputting means 84 for outputting closed area information for each line in which the kind of the side recognized by the recognizing means 83 is made the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for obtaining and outputting a closed area from vector data representing an outer shape.

[0002]

2. Description of the Related Art Desktop Publishing (DT)
In image processing such as P), PostScript is used.
In the case of using a relatively high-performance page description language (PDL) such as (Adobe), the user can arbitrarily set a clip area, and can create a highly flexible and appealing document.

On the other hand, in a system, the inside / outside determination of a clip area and a drawing figure is complicated, and the processing is taking time. Also, when multiple clips overlap,
In the PostScript language specification, the overlapped area becomes a new clip area (hereinafter, referred to as a multiple clip), but finding this overlapped area also requires complicated processing.

In Japanese Patent Application Laid-Open No. Hei 7-296172, an intersection between vectors is obtained based on vector (side) information constituting a clip, and new vector information of a multiplex clip is calculated.

Japanese Patent Application Laid-Open No. Hei 10-79038 discloses an edge list for drawing graphics and a dedicated clip edge list for clip processing, which supports multiplex clip processing. In this technique, when a clip area is determined by a scan line, software consisting of a simple processing loop can be implemented, and a multi-clip area can be determined by relatively simple processing without depending much on the complexity of a clip figure. .

[0006]

SUMMARY OF THE INVENTION However, Pos
In a page description language such as tScript, there is a clip path operator that returns clip graphic information held by the system to the user. When clip graphic information is held by vector calculation as in the technique disclosed in Japanese Patent Application Laid-Open No. 7-296172, extremely complicated processing such as calculation of intersections between vectors is required in the case of multiple clips. .

In the technique disclosed in Japanese Patent Application Laid-Open No. H10-79038, since information on a clip area is stored as a set of start coordinates and end coordinates for each scan line, an attempt is made to cope with a clip path operator. Then, information of all lines related to the multiplex clip is returned to the user, and a very large amount of information is handled.

[0008]

SUMMARY OF THE INVENTION The present invention is an image processing apparatus made to solve such a problem. That is, the image processing apparatus of the present invention includes a vector data generating unit that generates vector data representing an outer shape from drawing data to be drawn, and a scanning unit that scans the vector data generated by the vector data generating unit line by line. And recognition means for recognizing the type of side of vector data included in each line scanned by the scanning means, and output means for outputting closed area information for each line having the same type of side recognized by the recognition means And

According to the present invention, the type of the side of the vector data included in each line scanned by the scanning unit is recognized by the recognition unit, and as a result of the recognition, each line having the same side type is closed. Since the closed area information is output from the output unit as an area, it is possible to recognize the type of the side of the vector data by a simple process by scanning, and to output information regarding a set closed area based on the type of the side. Can be. That is, it is possible to output information about the area simply and with a small information amount.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of an image processing apparatus according to the present invention. FIG. 1 is a configuration diagram illustrating an image processing apparatus according to the present embodiment.
2 is an overall configuration diagram, and FIG. 2B is an internal configuration diagram of a clip path generation unit.

That is, as shown in FIG. 1A, the image processing apparatus according to the present embodiment comprises a drawing data input / output unit 1, a command control unit 2, a drawing data determination unit 3, a drawing data generation /
It comprises a storage unit 4, a clip data generation / storage unit 5, a paint / clip processing unit 6, an output unit 7, and a clip path generation unit 8.

The drawing data input / output unit 1 receives drawing data sent from a higher-level device such as a client, and stores and outputs the drawing data when a higher-level device requests drawing data.

The command control unit 2 is a part that receives commands from a higher-level device and sends control commands to necessary modules.

The drawing data determination unit 3 determines whether the target to be processed is a paint or a clip based on the command and the data.

The drawing data generation / storage unit 4 converts the drawing data from vector data to coordinate data intersecting the scan line, and stores the coordinate data.

The clip data generation / storage section 5 converts the clip data from vector data to coordinate data intersecting the scan line, and stores the coordinate data.

The paint / clip processing unit 6 superimposes a clip area on the drawing data and outputs the drawing data inside the clip to the output unit 7 as fill data. The output unit 7 outputs fill data and clip data.

The clip path generator 8 constructs a closed area from the clip coordinate data stored in the clip data generator / storage 5, and stores the closed area in the drawing data input / output unit 1.

As shown in FIG. 1B, the clip path generating unit 8 includes a vector data generating unit 81 for generating vector data representing an outer shape from drawing data, and a scanning unit 82 for scanning vector data line by line. A recognition unit 83 for recognizing the type and the like of the vector data included in each scanned line, and a closed region output unit 84 for outputting closed region information for each line having the same recognized side and the like. ing.

The vector data generation unit 81 and the scanning unit 82 constituting the clip path generation unit 8 are common to the modules applied to the drawing data generation / storage unit 4 and the clip data generation / storage unit 5. Is also good.

In such an image processing apparatus, when a client such as a personal computer or a workstation transmits command data described in a page description language (for example, PostScript) for image output via a network, This command is received by the command control unit 2 and the data is sent to the drawing data input / output unit 1.
To receive.

The command control unit 2 determines whether the received command is a command related to drawing, a command related to a clip, or another command, and notifies the drawing data determination unit 3 of a command related to drawing or a clip. .

The drawing data determination unit 3 notifies the drawing data generation / storage unit 4 of a command related to drawing among the received commands and vector data stored in the drawing data corresponding to the command, and relates to the clip. The clip data generation / storage unit 5 is notified of the command and the vector data stored in the drawing data corresponding to the command.

The drawing data generation / storage unit 4 stores vector data expressing the outline of a figure to be drawn,
Using a DA (Digital Differential Analyzer) or the like, coordinate data intersecting with the scan line is obtained, and stored in a coordinate memory storage unit such as an edge list in such a manner that all coordinate data on one scan line can be taken out.

FIG. 2 is a diagram for explaining an edge list.
That is, the edge list stores coordinate data obtained by DDA from all the vector data constituting the outline of the drawing figure, corresponding to the scan lines. Each row (y coordinate) of the edge list corresponds to each line of the scan line, and coordinate data generated by the DDA is sequentially stored in a column (x direction) corresponding to the row of the scan line.

To determine a column, a counter indicating the number of coordinate data currently stored in each row is provided, an initial value is set to zero, and each time one piece of coordinate data is stored, the counter of the corresponding row is incremented. The column to be stored is determined by referring to this counter value.

In this manner, all the coordinate data surrounding the outline of the figure are obtained. At this point, since the coordinate data generated from each vector is stored, for example, left-justified in the order of the vector to which the DDA is applied, a certain scan is performed. The order of the coordinate data in the line is not always arranged in the order of the magnitude of the value. Further, the painted area on a certain scan line has not been determined yet.

Therefore, the painted area on the scan line is determined by rearranging the coordinate data and referring to the inclination information. The determination of the painted area will be specifically described with reference to FIGS.

As shown in FIG. 3A, in this example, a star-shaped figure is painted according to a painting rule based on an even-odd winding rule. In addition, as a filling rule, other non-zero rules (non-zero winding rul
e).

In the star-shaped figure shown in FIG.
Vector line segments (hereinafter, referred to as paths) are drawn in the order of →→→→. In this pass, DDA is sequentially applied to generate coordinate data (coordinate data of the intersection) in each scan line from the start point to the end point, and the coordinate data is sequentially stored in the corresponding row / column of the edge list.

For example, as coordinate data where the scan line Ym intersects with each path, Xm0 is stored for the path, Xm1 for the path, Xm2 for the path, and Xm3 for the path.

In storing each coordinate data, the inclination information of the original path must be known. Specifically, some bits of the memory for storing the coordinate data are allocated, or a separate table is prepared to store the inclination information of the original path corresponding to each coordinate data.

As described above, the DDA
After the processing, the scan line Ym (m is 1 to n)
FIG. 4 shows the storage state of the coordinate data in (a natural number). Then, the coordinate data is rearranged for each row, for example, in ascending order.

Next, the inside of the drawing figure is determined based on the inclination information of these coordinate data and the painting rule (here, the odd rule). Specifically, for example, +1 for a positive slope,
For negative slopes, -1 is given. That is, as shown in a pattern 1 of FIG. 3B, a pattern in which the y-coordinate value increases in the direction of the arrow of the path (vector direction) has a positive slope. When the y-coordinate value decreases in the direction (vector direction), the slope is set to a negative slope, and the positive slope is given +1 and the negative slope is given -1.

Then, the inclination information corresponding to the rearranged coordinate data of each row is accumulated from the left with zero as an initial value.
In the scan line Ym shown in FIG.
m3, Xm1, Xm2, and Xm0 are rearranged in this order. As the slope information, a positive slope (+1) is assigned to Xm3, and a positive slope (+
1), Xm2 has a negative slope (-1), and Xm0 has a negative slope (-
1) is given. When the value corresponding to this inclination information is accumulated from the left with zero as an initial value, the result is 0 → 1 → 2 → 1 → 0.

In the case of this odd number rule, an odd section is a filled area, and in a non-zero rule, a section other than zero is a filled area. That is, according to the odd rule, the section from Xm3 to Xm1 is a filled area, the section from Xm1 to Xm2 is a non-filled area, and the section from Xm2 to Xm0 is a filled area.

This operation is performed for all the scan lines in the drawing area, the actual drawing area is determined, and sent to the output unit 7 (see FIG. 1) to form an image.

On the other hand, in order to realize a clipping process for performing a mask process with an arbitrary shape of the filled area, the image processing apparatus of this embodiment performs this process in the clip data generation / storage unit 5 shown in FIG. .

That is, the clip data generation / storage unit 5
When receiving the data related to the clip processing from the drawing data determination unit 3, when the clip is a single, for example, the outline of the clip figure is configured using the DDA as in the processing in the drawing data generation / storage unit 4. The coordinate data that intersects the scan line is calculated from the path to be executed, and the calculated coordinate data is stored in the edge list in a state corresponding to the scan line. Then, the coordinate data is rearranged, and the inside of the clip region is obtained, and the clip region for each scan line is obtained, similarly to the determination of the painted region.

In order to correspond to a clip path operator to be described later, the path data of the clip obtained from the drawing data input / output unit 1 is held. The path data is cleared when a command for instructing clip release is received from the host device or the like, and is held until then.

The clip data generation / storage unit 5
A mechanism is provided for determining whether the held clip coordinate data is generated from a single clip or from a plurality of clips. For example, m
A boolean named multi_clip (TRUE or F
(ALSE) as a global variable. This variable is FALSE at the time of initialization, for example, immediately after the start of the system, and is FALSE even when the first clip command is received. Next, when there are a plurality of clips, the state becomes TRUE.

When there are a plurality of clips, that is, when there are multiple clips, another method is used instead of the internal determination of the figure based on the accumulation of the inclination information used in the filled area. This method will be specifically described. Here, FIG.
As shown in FIG.
Are overlapped to form a multiplex clip.

First, when clip A and clip B overlap, when obtaining coordinate data from the path of each clip figure, a clip ID for distinguishing each clip (in this example, corresponding to clip A, A), and b) is added to the coordinate data corresponding to the clip B. The coordinate data sorted in ascending order by size comparison is prepared as a winding table having the number of lines by the number of clips (in this case, two lines), and the coordinate data of the corresponding clip ID is stored in one line. For example, the coordinate data on the left side of the same row is stored in a cell of another row in that column.

For example, as shown in FIG. 6, there are four pieces of coordinate data on the scan line Yn.
Xbn1, Xan1, Xan2, and Xbn2. In the winding table of clip A, Xan1 and 3 are stored in the second cell.
Xan2 is inserted in the second cell, and the winding tabl of clip B
e has Xbn1 in the first cell and Xbn2 in the fourth cell.
Enters.

Next, fl having the same matrix as the winding table
Prepare an ag table, and wind ta in each cell of the flag table.
From the inclination information (↑ indicates a positive inclination and ↓ indicates a negative inclination) added to the coordinate data of each cell corresponding to ble, the figure internal state of each row (for each clip ID) is obtained, and Sets, for example, a flag of 1.

Then, an area inside the clips of all IDs is obtained from the internal information of each ID in the flag table. In FIG. 6, an overlapping area [Xan1 on the scan line Yn in the two clips A and B is shown.
, Xan2]. This operation is repeated for all scan lines so as to obtain the internal area of the multiplex clip.

The drawing data generation /
The drawing data stored in the storage unit 4 and the clip data stored in the clip data generation / storage unit 5 are sent to the filling / clip processing unit 6, where clip processing is performed from both data on the same scan line. Actual drawing data on one scan line is obtained. Then, such drawing data is sent to the output unit 7 line by line, and is formed as entire image data.

The image processing apparatus according to the present embodiment is compatible with, for example, a clip path operator in the PostScript language specification in addition to the above-described image output operation to the output unit 7. The clip path operator refers to an operation of returning clip information held in the image processing apparatus to a higher-level device in a path format.

Hereinafter, the operation of the clip path operator will be described. First, when the command control unit 2 shown in FIG. 1 receives a command related to a clip path from a host device, the command control unit 2 notifies the clip path generation unit 8 of that.

Next, the clip path generation unit 8 executes the above-described mul stored in the clip data generation / storage unit 5.
With reference to the ti_clip variable, it is determined whether the clip is a single clip or a multiple clip. For a single clip path, the clip path generation unit 8 writes the clip path data held by the clip data generation / storage unit 5 to the drawing data input / output unit 1 as it is.

On the other hand, in the case of a multiplex clip, the clip path generating unit 8 forms a path composed of several closed areas based on the coordinate data in the clip edge list held in the clip data generating and storing unit 5. Then, the path data is written to the drawing data input / output unit 1.

Here, the path configuration in the case of a multiplex clip will be described. FIG. 7 is a diagram illustrating an example of a clip edge list of a multiplex clip, and FIG. 8 is a diagram illustrating determination of a closed region of a multiplex clip. In this description, an example is given in which the multiplex clip has an arbitrary pentagonal shape as shown in the left diagram of FIG.

The clip edge list shown in FIG. 7 stores coordinate data constituting a multi-clip graphic and is stored in the clip data generation / storage unit 5 (see FIG. 1). The coordinate data stored in the clip edge list includes a vector ID (a type of side) of a clip vector based on which the coordinate data is generated.
Is added.

For example, a vector ID (v1) is added to the first coordinate data Xa1 stored in the Ya line. This indicates that the coordinate data Xa1 is generated from the vector v1.

The clip path generation unit 8 examines the clip edge list, for example, line by line in ascending order of scan lines, for example, coordinate data and a vector ID added to the coordinate data, and determines the path of a closed region forming a multiplex clip. To build.

Specifically, from the Y0 line shown in FIG.
Recognition means 83 (FIG. 1) recognizes coordinate data and vector ID stored line by line up to the Y line (in the upward direction in the figure).
(See (b)).

In the example shown in FIG. 7, since there is no coordinate data from the Y0 line to immediately before the Ya line, no path is formed. Further, since there are two pieces of coordinate data in the Ya line, the Ya line is a start line of a scan line for forming a path. This start line is start_pa
It is stored in a variable named th_line.

The recognizing means 83 refers to the coordinate data and the vector ID of the next Ya 'line and compares them with the coordinate data and the vector ID of the previous Ya line. In this comparison, both the number of coordinate data and the vector ID match for the Ya line and the Ya 'line. For this reason, the recognizing unit 83 determines that the coordinate data of the Ya line and the coordinate data of the Ya 'line constitute one continuous path.

Similarly, the number of scan line coordinate data and the vector ID are compared line by line. Here, the number of coordinate data stored in the Yb line is 4
Is different from the previous two. That is, Yb
The line will not meet the requirements of the previous path construction. Therefore, the recognizing means 83 recognizes that the line from the line (here, the Ya line) stored in to the line Yb 'line immediately before the Yb line is one continuous path.

More specifically, the coordinate data Xa1, Xa2, Xb'1, X2 stored in the Ya line and the Yb 'line are stored.
For example, the following path is constructed from the four coordinate data b'2 (in the case of PostScript).

Xa1 Ya moveto Xb'1 Yb 'lineo Xb'2 Yb' lineo Xa2 Ya lineo closepath

Next, the recognizing means 83 starts the start_pa
The Yb line is stored in th_line, and the scan line is checked again from the Yb line. In the example of FIG.
Since the number of coordinate data is 2 on the Yc line,
It will be different from the previous four, start_pa
The path from the Yb line stored in th_line to the Yc 'line immediately before the Yc line is recognized as one continuous path.

Here, the coordinate data Xb1, Xb2, Xb3, Xb4 stored on the Yb line and the coordinate data Xc'1, Xc'2, Xc'3, Xc'4 stored on the Yc 'line are calculated. For example, the following path is constructed from the pieces of coordinate data (in the case of PostScript).

Xb1 Yb moveto Xc'1 Yc 'lineo Xc'2 Yc' lineo Xb2 Yb lineo closepath Xb3 Yb moveto Xc'3 Yc 'lineo Xc'4 Yc'neXc'4 Yc'ne Xc'4 Yc'ne

[0065] Again, the recognizing means 83 starts the start_pa
The Yc line is stored in th_line, and the scan line is checked again from the Yc line. In the example of FIG.
The number of coordinate data is also two in the Yd line,
The vector ID added to the coordinate data is v1, v4 on the Yc line, whereas it is v1, v5 on the Yd line, which is different from the previous vector ID. Therefore, the recognizing unit 83 sets the start_path_line
From the Yc line to the Yd 'line immediately before the Yd line are recognized as one continuous pass.

Here, for example, the following path is obtained from the four coordinate data of the coordinate data Xc1 and Xc2 stored on the Yc line and the coordinate data Xd'1 and Xd'2 stored on the Yd 'line. Construct (for PostScript).

Xc1 Yc moveto Xd'1 Yd 'lineto Xd'2 Yd' lineto Xc2 Yc lineo closepath

[0068] Again, the recognizing means 83 starts the start_pa
The Yd line is stored in th_line, and the scan line is checked again from the Yd line. In the example of FIG.
The number of coordinate data becomes 0 in the line following the Ye line, which is different from the number of coordinate data up to that time.
Therefore, the recognizing unit 83 sets the start_path_li
The line from Yd line to Ye line stored in ne is recognized as one continuous path.

Here, for example, the following path is constructed from the four coordinate data of the coordinate data Xd1 and Xd2 stored in the Yd line and the coordinate data Xe1 and Xe2 stored in the Ye line (PostScript Case).

Xd1 Yd moveto Xe1 Yelineto Xe2 Yelineto Xd2 Ydlineto closepath

By such an operation, a multiplex clip can be represented as a closed region represented by five paths as shown in the right diagram of FIG. The five paths recognized by the recognizing unit 83 are written from the closed area output unit 84 (see FIG. 1B) to the drawing data input / output unit 1 (see FIG. 1) and sent to the host device.

That is, even when the multiplex clip is represented by the coordinate data of each line, it is possible to transmit the information as a small amount of closed area information without transmitting the data to the host device as the data of each line.

In the above embodiment, an example has been described in which one continuous path is constructed when both the number of coordinate data and the vector ID stored corresponding to each scan line are the same. , Only the vector IDs may be compared, and if the vector IDs are the same, one continuous path may be constructed.

[0074]

As described above, the image processing apparatus according to the present invention has the following effects. In other words, the type of the side of the vector data included in each line can be easily obtained by scanning by the scanning means, and the closed area can be recognized by the recognizing means. Information on the area can be output to a host device or the like.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an image processing apparatus according to an embodiment.

FIG. 2 is a diagram illustrating an edge list.

FIG. 3 is a diagram for describing filling by an odd rule.

FIG. 4 is a diagram illustrating a storage state of coordinate data.

FIG. 5 is a diagram showing an example of a multiplex clip.

FIG. 6 is a diagram illustrating determination of a multiplex clip.

FIG. 7 is a diagram illustrating an example of a clip edge list of a multiplex clip.

FIG. 8 is a diagram for explaining a closed region determination of a multiple clip.

[Explanation of symbols]

Reference Signs List 1 drawing data input / output unit, 2 command control unit, 3 drawing data determination unit, 4 drawing data generation / storage unit, 5 clip data generation / storage unit, 6 paint / clip processing unit, 7 output Unit, 8 ... clip path generation unit, 81 ...
Vector data generation unit, 82: scanning means, 83: recognition means, 84: closed area output means

Claims (3)

[Claims] 1. Vector data generating means for generating vector data representing an outer shape from drawing data to be drawn, scanning means for scanning the vector data generated by the vector data generating means line by line, Recognition means for recognizing the type of the side of the vector data included in each line scanned by the means, and output means for outputting closed area information for each line having the same type of the side recognized by the recognition means. An image processing apparatus, comprising: 2. The image processing apparatus according to claim 1, wherein the output unit outputs the closed area information when a request for acquiring the closed area information is issued from a source of the drawing data. 3. The image processing apparatus according to claim 1, wherein said drawing data is composed of a page description language.