JP2000276476A - Method and device for vectorization of road map - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a method and device for road map vectorization which efficiently generate an integrated link to generate a road network in a shot time. SOLUTION: Road map data which are divided into meshes to be managed and have nodes set in many prescribed positions on roads and generation conditions of integrated links as well as generated integrated links are stored in storage devices 10 and 12 respectively, and the road map stored in the storage device 10 is displayed on a display device 3, and on the basis of generation conditions set by an integrated link generation condition setting part 6 which sets the conditions of integration of links which are information of line segments provided between nodes on roads, not only representative nodes are extracted from many nodes set on roads by an integrated link automatic generation part 7 but also a link having zero segment length is given to representative nodes placed across boundaries between meshes to generate the integrated links of segment lengths having representative nodes as start and end points. Integrated links generated by the integrated link automatic generation part 7 and an integrated link manual generation means 9 are displayed on a display device 3 by an integrated link display part 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road map for creating a road network by displaying, from a digitalized digital road map, nodes constituting roads and links as line segment information provided between the nodes. A vectorization method and apparatus.

[0002]

2. Description of the Related Art Digital road maps are based on GPS (Gro).
A high-accuracy map such as a distance and a position used in a car navigation system or a national land numerical information display system that supports a bal Positioning System is required. For this reason, nodes that are point information added to intersections of roads and the like are set with fine grain.

The digital road map is managed by dividing the digital road map into a mesh for the convenience of data maintenance. The number of nodes is 3,000 or more in one mesh in an area where roads are dense.

[0004] Considering all over Japan, the number of meshes of the digital road map provided by the Digital Map Association is 4500 or more, so the number of nodes is 13.5 million or more.

In a commercially available digital road map system, when searching for the shortest route on a nationwide scale,
For example, an algorithm that handles a distance matrix between nodes, such as the Dijkstra method described in the magazine “Information Structure” (published by Gijutsu Hyoronsha), is used. For this reason, an information processing function for a huge matrix having 13.5 million rows and columns each is required, making it difficult to search in real time.

In the traffic information providing system,
A good place where nodes are set as a place to place equipment such as vehicle detectors is appropriate, but due to the large number of them, installation of traffic sensors such as vehicle detectors is enormous cost. In addition, there is a possibility that real-time processing and provision of collected information may be lacking. Furthermore, in terms of traffic monitoring, due to the large amount of monitoring data,
Accurate monitoring may not be possible.

In order to solve such a large number of nodes or links, nodes that are important for search or monitoring (hereinafter also referred to as representative nodes) are extracted, and the extracted nodes are set as end points. It is conceivable to reconfigure the link, that is, the aggregated link, to reduce the number of nodes and the number of links. In order to do this, conventionally, there has been proposed a method of manually extracting important nodes by using a tool such as CAD, or a method of tracing and extracting a map as described in Japanese Patent Application Laid-Open No. 10-78752. Have been.

[0008]

The task of consolidating nodes or links making up a digital road map is important from the viewpoint of improving the performance in information processing and accurate road monitoring. However, the conventionally proposed method has a problem that it requires a lot of time because a large amount of manual work is required, a road network cannot be created in a short time, and the cost increases.

An object of the present invention is to provide a method and an apparatus for vectorizing a road map, which can efficiently create an aggregated link and create a road network in a short time.

[0010]

A feature of the present invention is that a node is set between a plurality of nodes set at a plurality of predetermined positions on a road in a digital road map which is managed by being divided into meshes. When the link which is the line segment information to be provided is displayed on the display means and a road network is created for each road type, the road on which the network is to be created is designated and displayed on the display means, and displayed on the display means. A representative node is extracted from a number of nodes set on a road, and a link having a line segment length of zero is assigned to the representative node extending between meshes. The aggregated link is generated and displayed on the display unit so as to overlap with the designated road.

According to the present invention, a road on which a network is to be created is displayed on the display means, a representative node is extracted from a large number of nodes set on the road, and a representative node extending between meshes has a line segment length of zero. And an aggregated link having a line segment length with the representative node as a start point and an end point is generated. Therefore, it is possible to efficiently generate the aggregated link and to create the road network in a short time.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention.

In FIG. 1, an input device 1 inputs coordinate data (x, y) to a map vectorizing device 4, and a mouse, a light pen or the like is used. . The storage device 10 stores intersections on roads and attributes of roads (for example, changing points such as the number of lanes), point data provided on roads (hereinafter referred to as nodes), and line segment data having two nodes as end points. A digital road map (hereinafter, also referred to as DRM) data composed of (hereinafter, referred to as a link) is stored. The road map data in the storage device 10 is stored in the storage device (DRA).
M) 11 is stored in the road map display unit 5.

The storage device 12 stores aggregated line segment information (hereinafter, referred to as an aggregated link) created by grouping nodes (hereinafter, also referred to as aggregated), and aggregated link generation conditions (eg, Condition data of a road to be consolidated). Aggregated link data and condition data of the storage device 11 are stored in a storage device (DRAM) 13 and are automatically generated by an aggregated link generator 7 and an aggregated link manual generator 9.
It is taken in.

The road map display section 5 inputs the DRM data fetched from the storage device 11 to the display device 3 via the interface 14, and displays a road map. The aggregated link generation condition setting unit 6 sets the aggregated link generation condition specified by the input device 1.

The aggregated link automatic generation unit 7 automatically generates an aggregated link from digital road map data. Aggregated link manual generator 9 Manually adds an aggregated link to the aggregated link created by the aggregated link automatic generator 7.

The aggregated link display unit 8 gives the aggregated links created by the aggregated link automatic generation unit 7 and the aggregated link manual generation unit 9 to the display device 3 via the interface 14 and displays them.

The map vectorizing device 4 comprises a road map display unit 5, an aggregated link generation condition setting unit 6, an aggregated link automatic generation unit 7, an aggregated link display unit 8, and an aggregated link manual generation unit 9. As the map vectoring device 4, a personal computer, a workstation, a parallel computer, a microcomputer or the like is used.

The general operation of the embodiment shown in FIG. 1 will be described with reference to the flowchart of FIG.

The road map display section 5 fetches digital road map data stored in the storage device 10 in step S10. The road map display unit 5 gives the road map data to the display device 3 via the interface 14 and displays the data (step S20). The road condition is confirmed on the road map displayed on the display device 3.

In step S30, an aggregated link generation condition such as an aggregated link generation target range and a road type is input from the input device 1 and set in the aggregated link generation condition setting unit 6. In step S40, it is determined whether the generation target range extends over a plurality of meshes or a single mesh.

In the case of a single mesh, the process proceeds to step S50, where the automatic aggregation link generation unit 7 executes an aggregation link generation process using a single mesh. If the generation target range extends over a plurality of meshes, the process proceeds to step S60, and the aggregated link automatic generation unit 7 executes an aggregated link generation process using a plurality of meshes.

The aggregated link generated by the aggregated link automatic generation unit 7 is stored in the storage device 13 and displayed on the display device 3 by the aggregated link display unit 8 (step S7).
0). The aggregated link generated by the aggregated link automatic generation unit 7 is displayed on the display device 3 and confirmed by the operator. As a result of the confirmation, if the operator needs to add, modify, delete, or otherwise edit in Step S60, the operator manually generates the aggregated link manually (Step S80).

The generated aggregated link is stored in the storage device 13.

Although FIG. 2 shows the case where manual generation is performed after the automatic generation processing of the aggregated link, the manual generation of the aggregated link alone or the degree of manual generation of the aggregated link may be automatically performed.

The general operation of the embodiment shown in FIG. 1 has been described above, and will be specifically described below.

FIG. 3 shows the structure of a digital road map (DRM).

FIG. 3 shows that the DRM displays the types of roads that are equal to or greater than the main local roads, specifically, express highways, urban expressways, general national roads, and main local roads. Other road types include general prefectural roads and other roads.

The digital road map is shown in FIG.
Map data is stored and managed for each mesh divided into rectangles by vertical and horizontal lines. By dividing the mesh into such meshes, it is possible to improve the maintainability and operability of the map data.

The map data divided into meshes is stored in the storage device 10 having a mesh number composed of a row number and a column number as a file name. For example, a digital road map created by the Digital Map Association is managed by adding a secondary mesh code introduced in the magazine "Numeric Map User's Guide (revised version)" (edited and published by the Japan Map Center). Have been.

In FIG. 3, the upper left corner is used as a reference mesh 00, row numbers are set in the vertical direction, and column numbers are set in the horizontal direction. A mesh number is specified by a set of a row number and a column number. Managing. In FIG. 3, the row number and the column number are one digit, but when the number of meshes increases, the number of digits of the row and column numbers is increased.

FIG. 4 shows an example of the structure of DRM node data. Nodes on the road in DRM
These points are provided at intersections, attribute change points, mesh boundary points, and the like, and are managed by assigning unique numbers within the mesh, that is, node numbers. Considering the uniqueness in the mesh, considering all the meshes, the node number is duplicated and the node cannot be specified. Therefore, the mesh number also forms the node data as shown in FIG.

The node type is used to distinguish whether the node is a mesh boundary node, an attribute change point node, a dead end node, or the like. When the node is a mesh boundary node, the joint mesh number and the joint node number are used to define which mesh and node are connected to the end of the road.

The node data also has the number of connected links and the number of connected link nodes. Digital road map is 2
A road is formed by a set of links that are line segments defined by two nodes. Therefore, the node has the number of connected links and the number of connected link nodes in order to specify how many links are connected and which node at the other end of the link is connected.

The node data has coordinate data (x, y) on the display of the node. Further, it is desirable that the latitude / longitude information of the map is also configured as node data.

FIG. 5 shows an example of the structure of DRM link data.

A link is a line segment composed of two nodes, and between nodes also has interpolation point information for expressing a curve. Links are similar to nodes,
It has a link number that is unique in the secondary mesh, and has a mesh number to identify which link of which mesh. The link data includes a start node number and an end node number which are end points of the link, a link type which is a road type of a road indicated by the link, a link length (unit: m), the number of the interpolation points, and It has the coordinates (x, y) of the interpolation point.

FIG. 6 is an example in which the area (A) of the meshes 20 and 21 in FIG. 3 is enlarged and displayed. Black circles in FIG. 6 are nodes, and-are links.

FIG. 7 shows an aggregated link generation condition setting screen 60 displayed on the display device 3 when the aggregated link generation condition is set in the aggregated link generation condition setting unit 6 by the input device 1.

The aggregated link generation condition setting screen 60 includes an additional mesh input area 61 for inputting a mesh number of a mesh for generating an aggregated link, a generation target mesh list 62 for displaying a list of input mesh numbers, and a generation target mesh list. A scroll bar 63 for scrolling the mesh list 62, a generation target road selection area 64 for selecting a road type to be consolidated, and a condition setting switch 65 for outputting set conditions to the storage device 13 are displayed. Is done.

As shown in the screen shown in FIG. 7, the range in which the aggregated links are generated and the road type can be set as conditions, so that the created aggregated links can be managed at the same level for each range, and the aggregated links can be hierarchically arranged. Can manage. For example, all the meshes in Japan are set as the aggregated link generation target area, and the aggregated links created only with the target road as the national highway are set as Layer 1, such as the Kanto region and the Tohoku region.
The whole country is divided into blocks, a mesh defined for each block is set as a generation target range, and a layer that manages an aggregated link created for all roads with the target road for each block can be set as a layer 2.

FIG. 27 shows an example of a conceptual diagram when the aggregated links are hierarchically managed.

Layer 1 covers the whole area of the aggregated link generation in Japan and the target road is a trunk road such as a national highway. Layer 2 divides the whole country into blocks such as the Kyushu region and the Shikoku region. If the meshes defined for each are set as the aggregated link generation target range and the generation target roads are roads equal to or greater than the main local roads, Layer 3 sets each of the meshes constituting the block-divided area as the aggregated link generation target range and all target roads The case where the aggregated link is generated as the road of FIG.

Since a hierarchical aggregated link can be created in this way, for example, when a shortest route search is performed in a wide range such as a nationwide scale, the representative node and the number of aggregated links are obtained by using the aggregated link of Layer 1. Is reduced,
You can search fast. The conditions of the road to be generated may be a width, the number of lanes, or the like, in addition to the road type.

FIG. 8 is a table of a digital road map in the case where the mesh 20 of FIG. 3 is set as a generation target mesh and roads equal to or larger than the main local roads are set as generation target roads on the aggregated link generation condition setting screen 60 shown in FIG. This is an example.

In FIG. 8, white circles ○ are nodes of the digital road map, numbers are node numbers, − are links of the digital road map, and <numerals> are link numbers. It can be seen that there is only one link between nodes and that the links in the digital road map are undirected segments.

Here, a plurality of meshes can be targeted as the aggregated link generation target mesh as described above. In this case, it is determined whether the input mesh becomes an enclave. An enclave means a case where the corners of a mesh are in contact with each other, or a case where a mesh or a group of meshes are separated. When the enclave exists, the road network constituted by the generated aggregated links is disconnected. When disconnected, it is difficult to solve network problems such as the shortest route search function.

Whether or not there is an enclave is determined when a mesh is added or when the condition setting switch 65 is selected by the input device 1. In the former case, considering the row number obtained by adding or subtracting 1 to the row number forming the mesh number of the input mesh, and the column number obtained by adding or subtracting 1 to the column number, fixing the row number of the mesh, Determine whether a mesh with a mesh number with a changed column number or a mesh with a fixed column number and a mesh number with a changed row number is already in the input mesh Is determined.

For example, when the mesh 21 shown in FIG. 3 is input as a generation target mesh, since the row number is 2 and the column number is 1, the variable row numbers are 3 and 1, and the variable column numbers are 2 and 0. be able to. Here, if the mesh 22, the mesh 20, the mesh 31, and the mesh 11 already exist, the input mesh 20 is not an enclave. However, when the mesh is input first, the enclave determination is not performed.

On the other hand, in the latter case, as described in Japanese Patent Application Laid-Open No. Hei 10-123947 previously proposed by the present applicant, it is determined whether or not an adjacent mesh of a mesh exists in the mesh list. The determination is made by checking the target mesh.

FIG. 9 shows the configuration of the aggregated link generation condition data set on the aggregated link generation condition setting screen 60 shown in FIG.

From the expressway national road use flag to the other road use flags, 0 or 1 is stored, and the road of the flag in which 1 is stored is the road for which an aggregated link is to be generated. The number of meshes to be generated is the number of meshes for which an aggregated link is to be generated, and the mesh numbers for aggregated link generation are stored after mesh number 1.

FIG. 10 shows a detailed flow of the automatic aggregation link generation performed by the automatic aggregation link generation unit 7.

First, digital road map data of a mesh for which an aggregated link is to be generated is read from the storage device 10 (step A). From the read digital road map data, link data (information) for which an aggregated link is to be generated is extracted (step B). Link extracted
Based on the data, end nodes constituting each link, that is, start node data and end node data (information) are extracted (step C). Next, among the nodes extracted in step C, an important node is extracted as a representative node (step D).

FIG. 11 shows a display example of the representative nodes when the aggregate link generation target mesh is only one of the meshes 20 in FIG.

In the example of FIG. 11, a black circle represents a representative node, and the number of links for which the aggregate link generation target connected to the node is a branch point of a road, a mesh boundary node, and a dead end node, that is, three or more. Alternatively, a node having one node is set as a representative node. This representative node can be used when creating a distance matrix between nodes referred to by an algorithm for a network problem such as the shortest route search.

As the representative node, a node which is considered important in industry or traffic control, such as a node provided at a location where the width, the number of lanes, and the line number changes, is also used as the representative node. It can be.

Returning to FIG. 10, a network is created by creating an aggregation link with the representative node as the start point and the end point node (step E).

The road network is generated in this manner. The details of the representative node extraction step of step D and the network generation step by the representative node of step E in FIG. One case and a case of a plurality of meshes will be described separately. This is because, when a plurality of meshes are to be the target meshes for generating the aggregated links, nodes that exceed the meshes are aggregated due to road continuity.

FIG. 12 shows a case where an aggregated link is generated by a single mesh in step S50 in FIG.
When the number of the target links connected to the node as shown in FIG.
It is a representative node extraction processing detailed flow when extracting more than one or one node as a representative node.

First, for the end point node of the link for which the aggregated link is to be extracted extracted in step C of FIG. 10, it is determined whether or not the link (connected link) connected to the node is the link for which the aggregated link is to be generated. The determination is made by comparing with the link extracted in B (step D1).
If the connection link is not an aggregate link generation target, it is determined whether the next connection link of the node is a generation target.

If it is determined in step D1 that the connection link is to be generated, 1 is added to a counter (not shown) initialized to 0 (step D2). The processing from step D1 to step D2 is repeatedly executed for the number of connected links of the link (step D3).

Next, the counter selected by the processing from step D1 to step D2 is checked to determine whether or not the counter is larger than two. That is, it is determined whether or not the number of aggregated link generation links connected to the node is three or more (step D4). If the counter is 2 or less at step D4, it is determined whether the counter is 1. That is,
Aggregated link generation target link connected to the node is 1
It is determined whether or not it is a book (step D5). If the counter is 1, the node is registered as a representative node (step D6). If the counter is not 1 in step D5, the process proceeds to step D7. If the counter is larger than 2 in step D4, it is registered in the representative node.

The processes from step D1 to step D6 are repeated by the number of end nodes of the link to be aggregated link extracted in step C of FIG. 10 (step D7), and a representative node is extracted.

FIG. 13 shows the structure of representative node data. The representative node data includes a mesh number and a node number to which the node belongs.

FIG. 14 is a processing flow for generating a network using the representative nodes extracted in step D of FIG.

First, one extracted representative node is taken out.
The connection link of the representative node is determined from the node data extracted in step C of FIG. 10 (step E1).
It is determined whether or not the connection link determined in step E1 is the aggregation link generation target link extracted in step B of FIG. 10 (step E2).

If the determined connection link is not a link for which an aggregated link is to be generated, the next connection link of the representative node is determined. If the determined connection link is the link to be subjected to the aggregation link generation, the representative node is registered as the start node of the aggregation link (step E3).

Next, the connection link node of the connection link thus determined is substituted for a prepared node variable (step E4). The node variable is used as an argument in the aggregation processing in step E5. In step E5, the process of consolidating the constituent nodes of the consolidation link with the representative node as the start node is executed. In step E6, the processing from step E1 to step E5 is repeated for the number of connected links of the representative node.

When the generation of the aggregated link starting from one representative node is completed through steps E1 to E6, the processing from step E1 to step E6 is repeated by the number of the representative nodes extracted in step D (step E7).

FIG. 15 shows the flow of the aggregation link configuration node aggregation processing in step E5 of FIG.

First, the node variable secured in step E4 in FIG. 14 is given as an argument, and it is determined whether or not the node is a representative node (step E51).
If the node is not a representative node, the node is registered as an interpolation node of the aggregation link (step E52).
A link constituted by the registered interpolation node and the previously registered node is determined from the link to be aggregated link extracted in step B of FIG. 10, and the link length of the link is added to the link length of the aggregated link ( Step E53).

Next, the connection link of the node registered in step E52 is determined (step E54), and it is determined whether the determined connection link is the aggregated link generation target link extracted in step B of FIG. 10 (step E5).
5). If the connection link determined in step E55 is not the link to be aggregated link generation, the next connection link in the node registered in step E52 is determined to determine whether or not it is the link to be aggregated link generation.

If it is determined in step E55 that the connection link is an aggregation link generation target link, the connection link node of the connection link is substituted into a node variable (step E56).
The aggregation processing of the configuration nodes of the aggregation link is continued (step E57). Aggregation processing is performed recursively.

At step E51, if the node given as the argument is the representative node, the node is registered as the end node of the aggregated link, and, as in step E53, the node registered this time and the node registered previously are used. The link to be configured is determined from the link to be aggregated link generation, and the link length of the determined link is added to the link length of the aggregated link (step E58). In step E59, since one aggregated link can be formed in step E58, the number of aggregated links is added.

FIG. 16 shows the data structure of the aggregation link.
The representative node, which is the terminal node of the aggregated link, is registered in the start node mesh number, start node number, end node mesh number, and end node number of the aggregated link data. The link length stores a value obtained by adding the link lengths of the links constituting the aggregated link. The number of interpolation nodes stores the number of nodes other than the end points, that is, the number of interpolation nodes, among the nodes forming the aggregated link. The mesh number of the interpolation node and the node number of the interpolation node are substituted for the interpolation node mesh number and the interpolation node number.

FIG. 17 shows a display example of an aggregated link when an aggregated link is generated by the representative node shown in FIG. As is clear from FIG. 17, it can be understood that nodes other than the representative node are not displayed in an aggregated manner.

Next, a description will be given of a network generation process by an extracted representative node when a plurality of meshes (hereinafter, also referred to as a composite mesh) are aggregated link generation target meshes.

FIG. 18 shows mesh 20 and mesh 2 shown in FIG.
It is an example of a digital road map display when 1 is set as an aggregated link generation target mesh.

In FIG. 18, white circles are the nodes of the digital road map, and the numbers are the node numbers. -Is the link of the digital map, and <number> is the link number.

Here, the node with the node number 14 in the mesh 20 and the node with the node number 5 in the mesh 21 at the boundary between the mesh 20 and the mesh 21 are the same point on the road. The node with the node number 26 in the mesh 20 and the node with the node number 2 in the mesh 21 are also the same point on the road.

FIG. 19 shows an example of a representative node in the composite mesh shown in FIG. Black circles are representative nodes.

In the case of the composite mesh, as in the case of the single mesh, a dead end node and a branch node of the road are used as the representative nodes. Even if the number of links is one, the number of connection links that are aggregate link generation target links of the joining node of the node is 1
In the case of a book, the node is not a representative node. For example, in FIG. 19, the node of the node number 14 of the mesh 20 and the node number 5 of the mesh 21
Node corresponds.

Even if the number of connection links that are aggregate link generation target links is two, a connection link that is a mesh boundary node and that is an aggregate link generation target link of a junction node in the junction mesh of the node. If the number is one or more, the node becomes a representative node. For example, in FIG. 19, the node with the node number 2 of the mesh 21 corresponds to this. In this case, the joining node of the node is also the representative node. For example, in FIG. 19, the node having the node number 26 of the mesh 20 corresponds to this.

The reason why the definition of the single mesh and that of the representative node are different in the composite mesh is that the roads are connected even if they exceed the mesh. In addition, there is no link beyond the mesh in the digital map data. Therefore, in the present invention, a logical link, namely,
A zero-length link (hereinafter referred to as a dummy link) is provided between the meshes, and an aggregated link is generated in consideration of road connectivity.

FIG. 20 shows a representative node extraction processing flow in a composite mesh executed by the aggregated link automatic generation unit 7.

First, by the same processing as the processing from step D1 to step D3 in FIG. 12, the number of the joining links as the aggregate link generation target links at the end node of the aggregation link generation target link extracted in step C in FIG. Is obtained (step D'1). Next, it is determined whether the acquired number of connection links is greater than two, that is, three or more (step D′ 2).

If the number of connection links is larger than 2, the node is registered as a representative node (step D'1).
0). In step D'2, if the number of connection links is two or less, it is determined whether or not the number of connection links is two (step D'3). Here, if the number of connection links is 2,
Next, it is determined whether or not the node is a mesh boundary node (step D'4).

If it is determined in step D'4 that the node is not a mesh boundary node, the processing shifts to the repetition processing of step C 'of step D'11 for the number of extracted nodes. If it is determined in step D′ 4 that the node is a mesh boundary node, the same processing as in step D′ 1 is performed on the joining node to acquire the number of connection links of the joining node. If there is no joint node, or if the joint mesh is not the aggregate link generation target mesh,
The number of connection links is 0.

Next, it is determined whether or not the number of connection links of the joining node is larger than 0 (step D'6). If it is larger than 0, the node is registered as a representative node (step D'10). If the value is equal to or smaller than 0, the process proceeds to the repetition process of step D′ 11.

In step D'3, when it is determined that the number of connection links of the node is not two, that is, when the number of connection links is one, whether the node belongs to the outer frame of the mesh for which the aggregated link is to be generated is determined. Or a dead end node, that is, a node within the mesh (step D'7). In addition, in order to determine whether or not the node is an outer frame, it is possible to extract the joint mesh number of the node and determine whether the joint mesh number is within the aggregated link generation target mesh.

If it is determined in step D'7 that the node is an outer frame node or a mesh node, the process proceeds to step D'10, and the node is registered as a representative node.

On the other hand, if it is determined in step D'7 that the node is neither an outer frame node nor a node in the mesh, that is, it is determined that the node is merely a mesh boundary node, the connection link of the junction node in the junction mesh is changed. It is acquired by the same processing as in step D'1 (step D'8), and it is determined whether the acquired number of connected links is larger than 1 (step D'9). In step D'9, if the number of connected links is larger than 1, the process proceeds to step D'10, and the node is registered as a representative node. If smaller than 1, the process proceeds to step D'11.

A series of processing from step D′ 1 to step D′ 10 is executed on all end nodes of the link to be aggregated link extracted in step C of FIG. 10 (step D′ 11) to extract a representative node. .

FIG. 21 shows a network generation flow when a composite mesh executed by the automatic aggregation link generation unit 7 is used as an aggregation link generation target mesh.

In the case of the composite mesh, steps E1 to E1 are performed similarly to the generation flow in the case of the single mesh of FIG.
Steps E′1 to E′5 corresponding to E5 are executed to perform the aggregation processing of the constituent nodes of the aggregation link using the node variables as arguments. The processing from step E′1 to step E′5 is repeatedly executed for the number of connected links of the representative node (step E′6).

In the case of a composite mesh, a process of creating a dummy link when the representative node is a mesh boundary node, that is, a zero-length aggregated link (hereinafter referred to as a dummy aggregated link) (step E ′). Execute 8). The processing from step E′1 to step E′7 is repeated by the number of extracted representative nodes (step E′7),
An aggregated link is created when a plurality of meshes are aggregated link generation target meshes.

FIG. 22 shows a detailed processing flow of the aggregation processing step E'5 in FIG.

In the aggregation processing, first, it is determined whether or not the node input as an argument is a representative node (step E'51). If the input node is not the representative node, the input node is registered as the interpolation node of the aggregated link (step E'52). In step E'53, a link having the registered node and the previously registered node as end points is determined from the link to be aggregated link extracted in step B of FIG. 10, and the link length of the determined link is added to the link length of the aggregated link. I do.

Next, the connection link of the registered node is extracted (step E'54), and it is determined whether or not the extracted connection link is the link to be subjected to the aggregation link generation extracted in step B of FIG. 10 (step E '). '55). Step E'5
If the connection link extracted in step 4 is not the target link,
The next connection link of the registered node is determined. If the extracted connection link is the target link, the connection node of the connection link is substituted into a node variable (step E'56), and the process of consolidating the constituent nodes of the consolidated link is continued (step E'57). .

In step E'55, the aggregated link generation target road may not be found among the connection links of the registered nodes. This is because, among the connection links of the registration node, those that are links to be aggregated link generation have already been the interpolation links of the aggregation link, that is, the connection nodes that are links to be aggregated link generation are the interpolation nodes of the aggregation link. Because it is registered. In this case, it can be seen from the definition of the representative node in the composite mesh that the registered node is a mesh boundary node. Therefore, if there is no target in step E'55, the joining node of the registered node is substituted for the node variable (step E'58), and the aggregation processing is continued. At this time, a zero-length dummy link is incorporated into the aggregated link.

If the input node is determined to be the representative node in step E'51, the input node is registered as the end node of the aggregated link (step E'5).
9) A link having the input node and the previously registered interpolation node as end points is extracted from the link to be aggregated link extracted in step B of FIG. 10, and the link length of the extracted link is added to the link length of the aggregated link. (Step E'510), the number of aggregation links is incremented by 1 (Step E'511).

FIG. 23 shows a detailed flow of the dummy aggregated link creation processing step E'8 in FIG.

First, the joining node of the representative node is shown in FIG.
It is determined whether there is a node extracted in step C of step 0 (step E'81). In this process, it is determined whether or not the representative node is a mesh boundary node, not the outer frame of the aggregated link generation target mesh. If it is determined in step E'81 that the joining node is the node extracted in step C of FIG. 10, the representative node is registered as the start node of the aggregated link (step E'82).

Next, after the link length of the aggregated link is set to zero in step E'83, the process moves to step E'84, and the joining node is registered as the end node of the aggregated link. In step E'85, 1 is added to the number of aggregated links.

On the other hand, if it is determined in step E'81 that the joining node is not the node extracted in step C of FIG. 10, the process ends without generating a dummy aggregated link.

FIG. 24 shows meshes 20 and 2 shown in FIG.
7 shows an example of an aggregated link display when an aggregated link is generated by a representative node when one of a plurality of meshes is a target of aggregated link generation.

In FIG. 24, node number 2 of mesh 20
The node 6 and the node with the node number 2 of the mesh 21 are indicated with black circles, which are representative nodes, and it can be confirmed that a dummy aggregated link has been generated between them. Also, in FIG.
And the node having the node number 5 of the mesh 21 is not displayed. This is the node number 1 of the mesh 20.
1 and the result of aggregation as an interpolation node of an aggregation link having the node of node number 6 in the mesh 21 as an end point.

As is clear from the display examples shown in FIGS. 17 and 24, when the aggregated link is automatically generated, the mesh 20
A separate aggregated link is generated, such as an aggregated link having the node numbers 20 and 22 as end points. This is because the condition of the road to be subjected to the generation of the aggregated link is set without considering the connectivity as a network.

FIG. 25 shows an example in which a road other than the road to be generated set as a condition is displayed when such an unconnected network is generated. The white circles 端 are the end nodes constituting the links of the digital road map out of the condition, the numeral is the node number, and the numeral is the link number of the link of the digital road map out of the condition.

As described above, when the network by the aggregated link automatically generated by the aggregated link automatic generation unit 7 is not connected, a connected network is generated as follows.

The links and nodes of the digital road map constituting the roads other than the road for which the aggregated link is to be generated are displayed on the display device 3 using the mouse or the like constituting the aggregated link manual generator 9.
, And pick a node with a mouse or the like to add a non-target link to the aggregate link generation target link. Then, the aggregated link automatic generation unit 7 automatically generates the aggregated link again.

For example, the node number 16 of the mesh 20,
50, 51, and 21 are picked by the aggregated link manual generation unit 9, non-target links are calculated, and the calculated links are automatically added to the links to be generated.

To manually generate an aggregated link, for example,
As described in Japanese Patent Application Laid-Open No. 10-78752, the aggregated link composed of the node numbers 11 and 19 of the mesh number 20 and the node numbers 20 and 22 is deleted once, and the aggregated link is traced again. It can also be generated.

FIG. 26 shows a display example when an aggregated link is generated again through manual operation as described above.

The road network is created as described above. The road for which the network is to be created is displayed on the display means, and the representative nodes are extracted from a large number of nodes set on the roads and straddled between the meshes. A link having a line segment length of zero is assigned to the representative node, and an aggregated link having a line segment length with the representative node as a start point and an end point is generated. Therefore, it is possible to efficiently generate an aggregated link, and to create a road network in a short time.

In the above embodiment, the aggregated link generation range and the road type can be set as conditions, so that the created aggregated links can be managed for each range at the same level.
Aggregated links can also be managed hierarchically. And
Since hierarchical aggregated links can be created and managed in this way, a shortest route search can be performed at high speed over a wide area, for example, on a nationwide scale.

Furthermore, since the aggregated link can be automatically generated, the efficiency and cost for creating a practical road network can be reduced, and the generated aggregated link can be displayed, so that the validity of the aggregated link can be easily determined. Checks can be made.

In addition, since an aggregated link can be manually generated, a road that cannot be covered by automatic generation can be added as an aggregated link, and the quality of the created aggregated link can be improved.

[0121]

As described above, according to the present invention, an aggregated link can be efficiently generated, and a road network can be created in a short time.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the present invention.

FIG. 3 is a configuration diagram of digital road map data.

FIG. 4 is a configuration diagram of node data of a digital road map.

FIG. 5 is a configuration of a link data diagram of a digital road map.

FIG. 6 is a diagram showing an example of an enlarged display of a digital road map.

FIG. 7 is a diagram illustrating an example of an aggregated link generation condition setting screen.

FIG. 8 is a diagram illustrating an example of a digital road map display when an aggregate link generation condition is set.

FIG. 9 is a data configuration diagram of an aggregated link generation condition.

FIG. 10 is a flowchart of automatic generation of an aggregated link.

FIG. 11 is a diagram showing an example of representative node display in a single mesh.

FIG. 12 is a flowchart of representative node extraction in a single mesh.

FIG. 13 is a configuration diagram of representative node data.

FIG. 14 is a flowchart of network generation by a representative node.

FIG. 15 is a flowchart of an aggregation processing of an aggregation link configuration node;

FIG. 16 is a configuration diagram of aggregated link data.

FIG. 17 is a diagram showing an example of an aggregated link display in a single mesh.

FIG. 18 is a diagram showing an example of display of a digital road map in a composite mesh.

FIG. 19 is a diagram showing an example of representative node display in a composite mesh.

FIG. 20 is a flowchart of representative node extraction in a composite mesh.

FIG. 21 is a flowchart of network generation in a composite mesh.

FIG. 22 is a flowchart of the aggregation processing of the aggregation link configuration nodes in the composite mesh.

FIG. 23 is a flowchart of generating a dummy aggregated link.

FIG. 24 is a diagram showing an example of an aggregated link display in a composite mesh.

FIG. 25 is a diagram illustrating an example of display of a road that is not an aggregate link generation target.

FIG. 26 is a diagram illustrating an example of a display when an aggregated link is reconfigured by a road that is not an aggregated link generation target.

FIG. 27 is a conceptual diagram in a case where aggregated links are managed hierarchically.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Input device, 3 ... Display device, 4 ... Map vectorization device, 5 ... Road map display part 6 ... Aggregate link generation condition setting part, 7 ... Aggregate link automatic generation part, 8 ... Aggregate link display part 9 ... Aggregate link Manual generation unit, 10 to 14 storage device

Continuation of the front page F term (reference) 2C032 HB05 HB11 HB15 5B075 ND06 PQ02 UU13 9A001 BB01 BB02 BB03 BB04 GG06 HH24 HH28 JJ50 JJ77 JJ78 KK37

Claims (2)

[Claims] 1. A display means for displaying nodes which are respectively set at a number of predetermined positions on a road in a digital road map which is divided and managed in a mesh form, and links which are line segment information provided between the nodes. And a road network is created for each road type. A road for which a network is to be created is designated and displayed on the display means, and a number of roads set on the display means are displayed. A representative node is extracted from the nodes, and a link having a line segment length of zero is provided to the representative node extending between meshes, and an aggregated link having a line segment length starting and ending at the representative node is generated. A vectorization method for a road map, wherein the road map is displayed on the display unit so as to overlap a designated road. 2. An input device for inputting data, and first storage means for storing road map data divided and managed in a mesh shape and having nodes set at a number of predetermined positions on a road, respectively. Road map display means for displaying a road map stored in the first storage means on a display device; and aggregated link generation for setting conditions for integrating links which are line segment information provided between the nodes of the road. Condition setting means, second storage means for storing the generation condition of the aggregated link and the generated aggregated link, and a plurality of roads set for the road based on the generation condition set by the aggregated link generation condition setting means. A representative node is extracted from the nodes of the first node, a link having a line segment length of zero is assigned to the representative node extending between meshes, and an aggregate link having a line segment length starting and ending at the representative node is generated. Automatic link generation means; manual generation means for manually generating the integrated link; and integrated link display means for displaying the integrated link generated by the automatic generation means and the manual generation means on the display device A vectorization device for a road map, comprising: