JP2003296726A - Method, device and program for converting drawing and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drawing conversion method, a drawing conversion device, a drawing conversion program and a recording medium for reducing the burden of an operator and preparing a vectorized map of desired quality. <P>SOLUTION: This drawing conversion method for using a computer to convert a raster map into a vectorized map has a character string recognition step for recognizing a character string on the raster map an storing the position of the character string on the raster map, a vectorizing step for vectorizing a line segment on the raster map, a closed loop preparing step for preparing a closed loop composed of the closest line segment, tracking a line segment surrounding the character string with the line segment as a side at the position of the character string surrounding the recognized character string, and a graphics combination step for associating the character string with the closed loop information for registration. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to vectorization of maps, and more particularly to a drawing conversion method, a drawing conversion device, a drawing conversion program and a recording medium for converting a raster map.

[0002]

2. Description of the Related Art There is a technique for generating a vectorized map from a map drawn on paper. In this case, first, a plurality of paper maps are read by a scanner or the like and attached to individual positions to create one whole map. At this time, the correction of the distortion of the raster map read individually and the correction of the unnecessary parts (called reading noise) such as spots and short line segments caused by stains on the original paper map etc. Generate raster map data. By processing the corrected map data with software and an operator, vectorized map data was generated.

[0003]

However, in the prior art, when a paper map is rasterized and vectorized, one line on the paper map is broken into a plurality of broken lines (broken lines). ), Or one of the lines where two line segments intersected on the paper or both lines were cut and recognized. In addition, although two line segments are formed in a T shape on a paper map, they may be recognized as a cross shape.

On the other hand, in vector mapping, not only the line segments are vectorized, but also the range surrounded by each line segment (hereinafter, closed loop or polygon) is recognized as one individual management target (land etc.). , Managing is also an important purpose.

For this reason, first, vectorization is performed based on the raster map information, and in order to correctly recognize each line segment, the result of conversion by the operator is displayed on the screen. Check if it is not a broken line, if the line segments are not connected correctly, etc.
Corrections are made by applying technologies such as CAD. Next, it was necessary to register the polygons surrounded by the line segments one by one, together with the information such as the lot number, etc. In addition, since the work needs to be patient and the operator's work to make the correction is heavy, the quality of the created vector map is affected, which may cause a problem.

In view of the above problems, the present invention reduces the burden on the operator and creates a vectorized map of desired quality, a drawing conversion method, a drawing conversion device, a drawing conversion program and a recording. The purpose is to provide a medium.

[0007]

According to a first aspect of the present invention, there is provided a drawing conversion method for converting a raster map into a vectorized map by using a computer, wherein a character string on the raster map is recognized. A character string recognizing step of storing the position of the character string on the raster map, a vectorizing step of vectorizing a line segment on the raster map, and a position of the character string surrounding the recognized character string, A closed loop composed of the closest line segments, tracking a line segment surrounding the character string, and creating the closed line segment as an edge;
The method further comprises a figure combining step of registering the character string and the closed loop information in association with each other.

According to the first aspect, by performing a series of steps of the character string recognition step, the vectorization step, the closed loop creation step and the figure combination step, the operator's burden is reduced and a vector of desired quality is obtained. You can create a customized map.

According to a second aspect of the present invention, in the closed loop creating step, the two line segments are combined and newly virtualized on the condition that the end points of the two line segments are considered to coincide with each other.
It is characterized by generating one polygonal line.

According to claim 2, like the raster map,
Since a plurality of line segments can be expressed as one polygonal line, the processing of the operator can be reduced.

According to a third aspect of the present invention, in the closed loop forming step, the first line segment and the second line segment exist on a substantially straight line, and the end point of the first line segment and the second line segment are present. It is characterized in that a new virtual line segment connecting the end points is generated on condition that the distance from the end point of the line segment is less than or equal to a predetermined value.

According to the third aspect, a line segment that should be one originally may have been cut by noise or the like when a paper map is read by a scanner can be connected by the line segment. It will be possible.

According to a fourth aspect of the present invention, in the closed loop creating step, on the condition that the distance between the end point and the point on the line segment is not more than a predetermined value, the end point and the line segment It is characterized in that a new virtual line segment connecting points is generated.

According to the fourth aspect, the end points of the line segment and the points other than the end points of the line segment are the cut portions which may have been cut by noise when the paper map was read by the scanner. It is possible to tie in minutes.

According to a fifth aspect of the present invention, a portion regarded as overlapping the newly imaginary line segment and two line segments connected to the line segment is one line segment. Is characterized by.

According to the fifth aspect, since the information amount of the line segment is reduced by forming one line segment, the processing amount can be reduced.

According to a sixth aspect of the present invention, in the closed loop creating step, when the first line segment intersects with the second line segment, the end point of the second line segment is separated from the first line segment. If the distance to the intersection is less than or equal to a predetermined length value, the second
From the end point of the line segment to the intersection with the first line segment.

According to the sixth aspect, the first
It is possible to form a T-shaped portion where the second line segment intersects with the line segment and there is a possibility that it has become a cross shape.

The invention described in claim 7 is characterized in that the portion changed in the closed loop creating step is displayed so as to be visually recognizable.

According to the seventh aspect, by displaying the changed portion in a visually recognizable manner, the burden on the operator can be reduced.

The invention according to claim 8 is characterized in that, in the figure combining step, the line segment newly virtualized in the closed loop creating step is registered as a line segment.

According to the eighth aspect, the step of combining figures includes
A virtual line segment can be registered as a confirmed line segment.

The invention according to claim 9 is a drawing conversion device for converting a raster map into a vectorized map, wherein a character string on the raster map is recognized and the position of the character string on the raster map is recognized. A character string recognition means for storing
Vectorizing means for vectorizing the line segment on the raster map, and the position of the character string surrounding the recognized character string,
A closed loop composed of the closest line segments is traced to the line segment surrounding the character string, and closed loop creating means for creating the line segment as an edge, and graphic combining means for associating and registering the character string and the closed loop information. And having.

According to the ninth aspect, by having a series of means such as the character string recognizing means, the vectorizing means, the closed loop creating means and the graphic connecting means, the operator's burden is reduced and a vector of desired quality is obtained. It is possible to provide a drawing conversion device capable of creating a converted map.

The recording medium for recording the program is a recording medium such as a CD-ROM, a flexible disk or a magneto-optical disk (MO) for recording information optically, electrically or magnetically, or ROM. Various types of recording media such as a semiconductor memory that electrically records information such as a flash memory and a flash memory can be used.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration of a drawing conversion device according to an embodiment of the present invention. As shown in FIG. 1, the drawing conversion apparatus 10 is composed of an ordinary computer and software installed in the computer. Also, to generate a rasterized map,
The image scanner 12 may be provided.

Next, a hardware block diagram of the computer system of the drawing conversion apparatus 10 will be described with reference to FIG.

The computer system shown in FIG.
Input devices 22 connected to each other by a bus B
, Display device 23, drive device 24, and recording medium 2
5, the auxiliary storage device 26, the memory device 27, the arithmetic processing device 20, and the interface device 21.

The input device 22 is composed of a keyboard and a mouse operated by a user of the computer system, and is used to input various operation signals to the computer system. The display device 23 displays various windows and data necessary for operating the computer system. The interface device 21 is an interface for connecting the computer system to the network 18, and is, for example, a NIC (Network Interface Card).
And modem.

The program for operating the computer system is provided by a recording medium 25 such as a CD-ROM or downloaded through the network 18. The recording medium 25 is set in the drive device 24, and data and programs are installed in the auxiliary storage device 26 from the recording medium 25 via the drive device 24.

The auxiliary storage device 26 stores data and programs, and also stores necessary files and the like. The memory device 27 reads the program from the auxiliary storage device 26 and stores the program when the computer system is activated. The arithmetic processing unit 20 executes processing according to the program read and stored in the memory unit 27.

The hardware block diagram has been described above, and the processing of the drawing conversion apparatus 10 will be described below.
First of all, explanation will be given on the division of maps by municipality as a preparation.

FIG. 3 shows the entire area of a certain area by one raster map, and the coordinates are added to the image of the map. The area shown in FIG. 3 is decomposed into map units ordered by using alphabets A, B, ... FIG. 4 shows one of the decomposed maps "E", which is referred to as the alphabet map.

Then, as shown in the alphabet map frame E of FIG. 4, the alphabet map frame is composed of a smaller map. The map in FIG. 5 shows these maps. As described above, this map is a raster map to which coordinates have been added, and is normalized by removing blank spaces and correcting distortion.

The above processing will be described with reference to the flowchart of FIG. In step S101, a raster map is created in units such as municipalities. This can be created using the image scanner 12. next,
The drawing conversion device 10 performs a diagram division of the entire municipality map in step S102. This is the definition of the drawing number of the map shown in FIGS. 4 and 5. Next, the drawing conversion device 10
In step S103, each raster map is corrected. This correction is, for example, correction of noise and blanks or distortion caused by reading a map drawn on paper, and is correction performed before vectorization. Then, in step S104, a raster map in which public coordinates are added to the new raster map processed by the above processing is created.

Next, the image area batch extraction process performed on the raster map created by the above process will be described.

In the image area collective extraction process, first, the area number character representing the address drawn on the raster map is set to OCR (Optica).
l Character Reader) This is the process of recognizing as vectorized characters by conversion. Based on the relative position of the recognized character on the image, a lot number character is drawn at the corresponding coordinates on the map. This character is registered in the layer dedicated to the lot number among the map layers including a plurality of layers.

Next, as shown in FIG. 7, the drawing conversion apparatus 10 excludes the area where the vectorized lot number characters are present from the image of the raster map 30, and creates the raster map 32 from which the lot number characters are excluded. To do. Next, the drawing conversion device 10
As shown in the map 34 of FIG. 8, the created line segment on the raster map 32 is vectorized. By vectorizing the line segments, a line segment connecting the end points with a straight line as shown in the map 34 is created. For these line segments,
The points 38, 40, 42 where the end points overlap each other are combined to form a polyline (polygonal line) as shown in the map 36.

Next, the drawing converting apparatus 10 is a map frame 4 which is a frame of a map, as shown in a region shown by a dotted line in FIG.
Delete the polyline from 4 to a certain range (buffer). This is because, as shown in FIG. 10, there is a possibility that the contour lines of the drawing may be interrupted depending on the accuracy of scanning and the accuracy of the paper drawing. Draw a contour line.

Then, a polyline having a length of a specified value or less is deleted from the entire drawing. This is done in order to eliminate unnecessary vectors and register marks on the drawing, which are generated due to the quality of the paper drawing and the scanning condition, so that only the boundary lines are drawn.

Next, a correction process relating to polylines, such as joining of polylines, is performed. First, the processing when the end points of two line segments are included in a certain range as shown in FIG. 11 will be described. First, as shown in FIG.
When the line segments are present in a substantially straight line and the distance between the end points is shorter than a predetermined length, as shown in FIG. 11, the end points 46 and 48 are connected and the two line segments are connected in a straight line. Next, as shown in FIG. 11B, when the two line segments do not exist on a straight line, the end points 50 and 52 are not connected and are left as they are. Next, even in the case of a line segment that exists in a substantially straight line as shown in FIG. 11C, if the distance between the end points 54 and 56 is longer than a predetermined length, the two end points are not connected and are left as they are. To do.

Next, the connection between the line segment 58 and the end point will be described with reference to FIG. As shown in FIG. 12A, when the distance between the end point 60 and the line segment 58 is shorter than a predetermined length, the line segment 58 is extended from the end point 60 as shown in FIG. The end point 60 and the line segment are joined (L-shaped joint). However, as shown in FIG. 12, when the distance between the end point 62 and the line segment 58 is longer than a predetermined length, they are left as they are without being combined.

Next, the processing when the line segment 64 intersects with another straight line will be described with reference to FIG. First, Fig. 1
When the distance between the end point 66 and the line segment 64 is shorter than a predetermined length as in 3 (a), the T-shape is corrected (T-joint). As shown in FIG. 13B, when the distance between the end point 70 and the line segment 64 is longer than a predetermined length, it is left as it is. In addition, as shown in FIG. 13C, even when a polygonal line is formed after the intersections, the polygonal line is left as it is.

The above-described image area batch extraction and polyline correction processing are performed for all the maps defined in FIG. 3, for example.

It should be noted that several kinds of parameters are set in advance for the process of batch extraction of image areas and polyline correction. The parameters are "accuracy of coordinate values", "width of buffer from figure contour line", "distance between end points to be combined with polyline",
Five types of "distance between two figures to be joined to polyline" and "length of polyline to be automatically deleted" are included, and are used for determination such as joining in the above processing. Further, since it is possible to improve the accuracy by setting the parameters, it becomes possible to create a vectorized map of desired quality. Then, the polyline shaped in this way is registered in a layer dedicated to the brush field.

The process of vectorizing the raster map described above will be described with reference to the flowchart of FIG. In step S201, the drawing conversion device 10 recognizes the lot number character by extracting the lot number character on the raster map, and also recognizes and stores the position information of the lot number character. Next, in step S202, the drawing conversion device 10 extracts a line from the raster map and vectorizes the line segment. And
The drawing conversion device 10 initializes the vector map in step S203. For this initialization, resetting of the above-mentioned figure contour line, deletion of a line segment whose length is equal to or less than a specified value, or the like is performed. In the next step S204, the drawing conversion device 10
Recognize polygons. The process will be described with reference to the flowchart of FIG. In step S301, the drawing conversion device 10 sets the line segments on the map as shown in FIGS.
The line segment combining process described using No. 3 is performed. Next, the drawing conversion device 10 sets the recognized first lot number character code in step S302. In the next step S303,
The drawing conversion device 10 searches the nearest line segment from the center of the lot number character string. This process is a process of searching for the line segment closest to the lot number character.

Then, the drawing conversion device 10 carries out step S.
At 304, it is determined whether a polygon is formed by the line segment found by the above search. If it does not become a polygon, the drawing conversion device 10 determines whether or not there is a line segment connected to this line segment in the clockwise direction in step S305. When there is a line segment to be connected, the drawing conversion device 10 performs the process of step S304 again. If there is no line segment to be connected, the drawing conversion device 10 searches for a line segment outside the previously selected neighboring line segment as viewed from the lot number character string in step S306. This process is a process of searching for an outer line segment as viewed from the lot number character string next to the line segment selected previously. It should be noted that step S306 may be performed once or depending on the desired map usage policy, accuracy, etc.
You may make it advance to 308.

Returning to the process of step S304, when the line segment forms a polygon as shown in FIG. 16, the drawing conversion device 10 associates the extracted polygon and the lot number character string with the image lot number in step S307. Add as link information. Next, the drawing conversion device 10 performs step S
In step 308, the drawing conversion apparatus 10 determines whether or not polygons have been extracted for all the lot numbers in the drawing. If they have been extracted, the process ends. If they have not yet been extracted, the next lot number recognized in step S309. Set the character code,
The process of step S303 is performed again.

When the polygon is recognized in this way, the drawing conversion apparatus 10 corrects the vector map in step S205 of FIG. 14, and determines whether the vectorized map correction of step S206 is completed. If the correction is not completed, the drawing conversion apparatus 10 performs the process of step S205 to perform the correction again, and if the correction is completed, the process ends. It should be noted that, in the flowchart of FIG. 15, it is possible to determine whether or not the polygon has become the polygon of step S304 while performing the combination of the line segments of step S301. You may go to

Next, four functions for facilitating a manual correction work to be performed on a map on which a process such as collective extraction of image areas is performed will be sequentially described with reference to FIGS. 17 and 18. .

First, when the vectorized map is displayed, the ground polygon is hatched and the color of the lot number linked to the ground polygon (the diagonal line in FIG. 17) is changed and displayed. . And the second is FIG.
As shown in, the drawing conversion device 10 displays the end points in a rhombus and the bending points in a triangle so that the operator can easily see. Thirdly, when the mouse is selected, not only the shape near the coordinates of the displayed mouse cursor is highlighted, but if the target shape is an image ground polygon and a lot number character, a link is made. Emphasize the shapes that are present The fourth is
As shown in FIG. 18, the lot number is 123-5 and the lot number is 2
When there is the same coordinate point in the image ground polygon and the polyline, such as 58 and the contact point 74 of the image ground whose land number is 123, the contact point 74 can be moved like the contact point 76. This eliminates the need for the operator to make corrections for all polylines.

[0053]

As described above, it is possible to obtain the drawing conversion method and the drawing conversion apparatus for reducing the burden on the operator and creating a vectorized map of desired quality.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a drawing conversion device according to an embodiment of the present invention.

FIG. 2 is a hardware block diagram of a computer system.

FIG. 3 is a diagram showing a map defining drawing numbers.

FIG. 4 is a diagram showing a map in which drawing numbers are defined.

FIG. 5 is a diagram showing a map in which drawing numbers are defined.

FIG. 6 is a flowchart showing a process of creating a raster map.

FIG. 7 is a diagram showing how lot numbers are excluded.

FIG. 8 is a diagram showing how end points are combined.

FIG. 9 is a diagram showing how a polyline in a buffer is deleted.

FIG. 10 is a diagram showing a state in which a contour line is interrupted.

FIG. 11 is a diagram showing a case where end points are combined.

FIG. 12 is a diagram showing a state in which an end point and a straight line are combined.

FIG. 13 is a diagram showing processing of intersecting line segments.

FIG. 14 is a flowchart showing a vector map creation process.

FIG. 15 is a flowchart showing a polygon recognition process.

FIG. 16 is a diagram showing a ground polygon.

FIG. 17 is a diagram showing a method of displaying end points and bending points.

FIG. 18 is a diagram showing movement of contacts.

[Explanation of symbols]

10 ... Drawing conversion device 12 ... Image scanner 20 ... Arithmetic processing device 21 ... Interface device 22 ... Input device 23 ... Display device 24 ... Drive device 25 ... Recording medium 26 ... Auxiliary storage device 27 ... Memory devices 30, 32 ... Raster map 34 , 36 ... Maps 38, 40, 42, 46, 48, 50, 52, 54, 5
6, 60, 62, 66, 70, 72 ... End point 44 ... Drawing 58, 64 ... Line segment 74, 76 ... Contact

Continued front page    F-term (reference) 2C032 HB03                 5B050 AA01 BA07 BA17 EA06 EA13                       FA02                 5B057 AA13 CA12 CA20 CB12 CB17                       CF03 CG01 CH01 CH11 CH14                       DB02 DC16                 5B064 AA07

Claims (11)

[Claims] 1. A drawing conversion method for converting a raster map into a vectorized map using a computer, recognizing a character string on the raster map, and storing a position of the character string on the raster map. A character string recognizing step, a vectorizing step for vectorizing the line segment on the raster map, and a closed loop composed of the line segment closest to the position of the character string surrounding the recognized character string, A drawing conversion method comprising: a closed-loop creating step of tracking a line segment surrounding a column and creating the line segment as an edge; and a figure combining step of registering the character string and the closed-loop information in association with each other. 2. The closed loop creating step joins the two line segments at the end points on the condition that the end points of the two line segments are considered to coincide with each other to generate a new virtual line. The drawing conversion method according to claim 1, wherein: 3. The closed loop creating step comprises: a first line segment and a second line segment being present on a substantially straight line; and an end point of the first line segment and an end point of the second line segment. The drawing conversion method according to claim 1, wherein a new virtual line segment connecting the end points is generated on condition that the distance is equal to or less than a predetermined value. 4. The closed loop creating step creates a new virtual connection between the end point and the point on the line segment, provided that the distance between the end point and the point on the line segment is a predetermined value or less. The drawing conversion method according to claim 1, wherein a line segment is generated. 5. The line segment that is considered to overlap the newly imaginary line segment and two line segments connected to the line segment is one line segment. Through 4
The drawing conversion method described in any one of 1. 6. In the closed loop creating step, when a second line segment intersects with the first line segment, a distance from an end point of the second line segment to an intersection point with the first line segment is predetermined. From the end point of the second line segment to the first
The drawing conversion method according to claim 1, wherein the intersections with the line segment 1 are deleted. 7. The part changed in the closed loop creating step is
The drawing conversion method according to any one of claims 1 to 6, wherein the drawing conversion is performed so that the drawing can be visually recognized. 8. The drawing conversion method according to claim 1, wherein in the figure combination step, the line segment newly virtualized in the closed loop creating step is registered as a line segment. 9. A drawing conversion device for converting a raster map into a vectorized map, the character string recognition means recognizing a character string on the raster map and storing the position of the character string on the raster map. A vectorization means for vectorizing the line segment on the raster map; a closed loop composed of line segments closest to the position of the character string surrounding the recognized character string, and a line segment surrounding the character string. The drawing conversion device, comprising: a closed-loop creating unit that tracks the line segment and creates the line segment as an edge; and a graphic combining unit that associates and registers the character string and the closed-loop information. 10. A character string recognition procedure for causing a computer to recognize a character string on a raster map and storing the position of the character string on the raster map, and vectorization for vectorizing line segments on the raster map. A closed loop composed of a line segment closest to the position of the recognized character string that surrounds the recognized character string, a line segment surrounding the character string, and creating the closed loop as an edge. And a drawing conversion program for executing a figure combining procedure for associating and registering the character string and the closed loop information. 11. A character string recognition procedure for recognizing a character string on a raster map and storing a position of the character string on the raster map in a computer, and vectorization for vectorizing a line segment on the raster map. A closed loop composed of a line segment closest to the position of the recognized character string that surrounds the recognized character string, a line segment surrounding the character string, and creating the closed loop as an edge. And a computer-readable recording medium recording a drawing conversion program for executing a figure combination procedure of associating and registering the character string and the closed loop information.