Method and system for constructing geographic entity based on DLG topographic map

Abstract

The invention provides a method and system for constructing a geographic entity based on a DLG topographic map, and the method comprises the steps: taking the DLG topographic map as a data basis, and carrying out the objectification processing of basic geographic information elements; the method comprises the following steps: constructing a data graph based on an association relationship between geographic information elements and a target geographic entity in dimensions such as spatial scale, geometric morphology, geographic features, attribute expression and the like, belonging to a mapping conversion standard, and extracting an intermediate entity library from an objectified result library; entity construction operators are assembled according to needs to complete entity production scheme configuration, processing such as assembly and fusion is carried out on primitive objects in the middle entity library based on an entity production scheme, and rapid production and construction of geographic entity achievements are achieved.

Description

Technical Field

[0001] The invention relates to a method and system for constructing geographical entities based on a DLG topographic map. Background Art

[0002] Basic geographic entities are an important part of the real-life 3D China data product system. The mainstream 2D ​​geographic entity production solution is to use surveying and mapping results as the data base for data conversion production and entity assembly. The main steps include editing and transformation, data extraction, and primitive combination and fusion. Although this technical route has been applied, there are still some problems in each production link.

[0003] Among them, the editing and transformation of basic geographic information elements involves graphics repair, data segmentation and other tasks, which require a large degree of manual participation, and there are differences between the proficiency of operators and the experience of experts, which makes it difficult to control the quality of data processing; data extraction requires analysis of the mapping relationship between the source data and the result data, and between the geometry and attribute fields, but due to the inconsistency of the content, structure and organization of surveying and mapping results in various places, it is difficult to unify the data extraction plan; the requirements for the construction of geographic entities at different scales are different, and it is necessary to comprehensively consider the multiple spatial relationships, attribute relationships and primitive combinations between geometric elements. The existing entity construction methods cannot flexibly meet the personalized needs of geographic entity production in various places. For geographic information, we need to deal with some problems such as low automation, difficult quality control, map mapping plan management, and multi-scale geographic entity construction. Summary of the invention

[0004] In order to solve the above problems, the purpose of the present invention is to provide a method and system for constructing geographic entities based on DLG topographic maps, so as to solve a series of problems such as quality control difficulties, mapping conversion scheme management, diversified entity results data, and low degree of automation in the process of converting existing geographic information elements to construct geographic entities.

[0005] The present invention provides a method for constructing a geographical entity based on a DLG topographic map, collecting a DLG topographic map used to make a geographical entity;

[0006] Performing object-oriented processing on the DLG topographic map to obtain an object-oriented result library;

[0007] Performing data quality inspection based on the objectified results library;

[0008] Analyze the relationship between geographic information elements and geographic entities based on the object-oriented results library that has passed quality inspection;

[0009] Constructing a mapping rule between geographic information elements and geographic entities based on the association relationship between the geographic information elements and the geographic entities;

[0010] Storing the mapping rules in a file in a structured data format to form a standard production specification for geographic entities;

[0011] Perform geometric extraction conversion and attribute mapping based on geographic entity standard production specifications to obtain an intermediate entity library;

[0012] According to the content requirements of various entities, operators are built based on system entities to customize the entity production plan.

[0013] Optionally, the object-oriented processing of the DLG topographic map to obtain an object-oriented result library includes:

[0014] Based on the results requirements of geographic entities, convert the coordinate system of geographic information element data;

[0015] According to the requirements of geographic entity expression granularity, the point, line and surface elements in the multi-level geographic information element database are supplemented; according to the requirements of the expression of geographic entity geometric objects, the element objects in the multi-level geographic information element database are modified;

[0016] Based on the existing DLG data, the target ground object is automatically derived as the geometric compensation of the geographic entity graphic data;

[0017] Process the connectivity of spatial geometric objects with continuity characteristics;

[0018] The attribute value mapping dictionary is stored in the format of <original attribute content, current attribute content> to complete the entity processing of the attribute value of the geographic information element;

[0019] Consistency processing of topological relationships within and between layers of each geographic information element.

[0020] Optionally, the data quality check includes a representation quality check, a feature connectivity check, an attribute consistency check, a geometric validity check, and a topology consistency check.

[0021] Optionally, analyzing the association between geographic information elements and geographic entities based on the objectified achievement library that has passed quality inspection includes:

[0022] Based on the objectified results library that has passed quality inspection, the relationship between geographic information elements and geographic entities is analyzed from the aspects of the data's spatiotemporal characteristics, attribute characteristics, spatial relationship characteristics, etc., including geometric correspondence and the relationship between attribute fields and value domains.

[0023] Optionally, the mapping rules between the geographic information elements and the geographic entities include: classification code mapping rules, attribute content mapping rules, and geometric object mapping rules;

[0024] The classification code mapping rules include one-to-one mapping, one-to-many mapping, many-to-many mapping, and many-to-one mapping;

[0025] Attribute content mapping rules include direct mapping, combined mapping, translation mapping, and default value filling;

[0026] Geometric object mapping rules include single-element mapping, multi-element combination mapping, and multi-element fusion.

[0027] Optionally, the entity construction operator includes:

[0028] Single-element construction: Filter elements based on the attributes of SQL statements, and each entity is composed of a single element;

[0029] Single layer line intersection construction: within the same layer, when lines intersect at one or more points in space, line features are combined or fused to construct;

[0030] Single layer line penetration construction: When the lines intersect at one point in the internal space of the same layer and the point type is an endpoint, the line features are combined or fused to construct;

[0031] Single layer line first-line connection construction: When the lines intersect at one point in the internal space of the same layer, and the point type must be the starting point of one line and the end point of another line element, the line elements are combined or fused to construct;

[0032] Multi-layer line intersection construction: When multiple layers intersect at one or more points in space, line features are combined or fused to construct;

[0033] Multi-layer line construction: When multiple layers intersect at one point in space and the point type is endpoint, line features are combined or fused to construct;

[0034] Multi-layer line first-line connection construction: When multiple layers intersect at one point in space, and the point type must be the starting point of one line and the end point of another line feature, the line features are combined or fused to construct;

[0035] Line intersection surface construction: take the line as the selection element and the surface object as the target element, set the reuse of the primitives, and combine the line and surface elements that meet the intersection relationship to construct an entity;

[0036] Constructing intersecting lines: Use lines as selection elements and surface objects as target elements. Set the threshold of the length ratio of lines within the surface and the reuse of primitives. Combine line and surface elements that meet the intersection relationship to construct entities.

[0037] Common attribute construction: When the specified field values ​​have a value inclusion relationship between multiple graphs, they are combined or fused to support setting attribute constraints, null value constraints, etc. Each entity has two or more graphic elements;

[0038] Area inclusion construction: Use the area as the selection element, point, line, and area objects as the target elements, set the reuse of the primitives, and combine the point, line, and area elements that meet the full inclusion relationship to construct an entity;

[0039] Buffer construction: Within the same layer, each element sets a buffer based on parameters. When other elements exist in the buffer, the two elements are combined or fused to construct.

[0040] The present invention also provides a system for executing any of the above methods for constructing geographic entities based on DLG topographic maps, characterized in that the system is constructed based on the QT framework and combined with the geometric algorithm library of GDAL and GEOS.

[0041] The system includes a data processing module, a standard management module, a physical production module, and a quality inspection module.

[0042] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store program codes, and the program codes are used to execute any of the above-mentioned methods for constructing geographic entities based on DLG topographic maps.

[0043] The present invention uses the DLG topographic map as the data basis and performs object-oriented processing on the basic geographic information elements; based on the association between the geographic information elements and the target geographic entities in the dimensions of spatial scale, geometric form, geographic characteristics, attribute expression, etc., constructs data graphs and attribute mapping conversion standards, and extracts the intermediate entity library from the object-oriented result library; assembles the entity construction operator on demand to complete the entity production plan configuration, and assembles and fuses the graphic primitive objects in the intermediate entity library based on the entity production plan to realize the rapid production and construction of geographic entity results.

[0044] Based on the following detailed description of specific embodiments of the present invention in conjunction with the accompanying drawings, those skilled in the art will become more aware of the above and other objects, advantages and features of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0046] Figure 1 It is a schematic diagram of a method flow of constructing a geographic entity based on a DLG topographic map according to an embodiment of the present invention;

[0047] Figure 2 It is a schematic diagram of the overall scheme of a method for constructing a geographic entity based on a DLG topographic map according to an embodiment of the present invention;

[0048] Figure 3 is a schematic diagram of a coordinate system conversion tool of the system of the present invention;

[0049] Figure 4 This is a flow chart of collecting the outer contour of a house according to an embodiment of the present invention;

[0050] Figures 5a to 5d is a schematic diagram of the contents of an intermediate entity library according to an embodiment of the present invention;

[0051] Figure 6 It is a schematic diagram of an overall solution of a method for constructing a geographic entity based on a DLG topographic map according to another embodiment of the present invention;

[0052] Figure 7 It is a schematic diagram of the data extraction and conversion scheme mdb of an embodiment of the present invention;

[0053] Figure 8 This is a Json schematic diagram of the national highway entity construction rule of an embodiment of the present invention;

[0054] Fig. 9 It is a Json schematic diagram of the river entity construction rules of an embodiment of the present invention. DETAILED DESCRIPTION

[0055] The embodiments of the present invention are described below in conjunction with the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the present invention and are not limiting.

[0056] The present invention proposes a method for constructing geographic entities based on structured production specifications and using DLG topographic maps as basic data. Figure 1 As shown, the method for constructing geographic entities based on a DLG topographic map according to an embodiment of the present invention includes the following steps S1 to S8.

[0057] S1, collect DLG topographic maps for making geographic entities. DLG topographic maps have detailed spatiotemporal information of geographical objects and structured semantic description information, and are important map information sources for geographical entities. Before constructing geographical entities, it is necessary to collect DLG topographic maps for making geographical entities. Generally, DLG topographic maps contain all types of geographical features, such as water system geographical objects, transportation road network geographical objects, building geographical objects, etc.

[0058] S2, object-oriented processing is performed on the DLG topographic map to obtain an object-oriented result library. Figure 2 As shown, the objectification processing of geographic information elements in this embodiment may include coordinate system conversion, layer element supplementation, automatic extraction of land feature elements, geometric element connectivity processing, attribute mapping conversion based on JSON dictionary, and topological consistency processing.

[0059] In an optional embodiment of the present invention, the above step S2 performs object-oriented processing on the DLG topographic map to obtain an object-oriented result library, which includes:

[0060] S2-1, based on the results requirements of geographic entities, convert the coordinate system of geographic information element data;

[0061] Generally, the mathematical basis of geographic entity results usually requires the use of the 2000 National Geodetic Coordinate System (CGCS2000). Therefore, before constructing a geographic entity based on geographic information element data, the data coordinate system needs to be converted, that is, the geographic information element data that is not in the 2000 National Geodetic Coordinate System is converted into data in the 2000 National Geodetic Coordinate System. The coordinate system conversion is mainly completed with the help of the system provided by the present invention, and the specific steps include:

[0062] (1) running the system provided by the embodiment of the present invention, and loading the basic geographic information elements to be converted into the system;

[0063] (2) Run the "Reprojection Layer" tool in the data processing module of this system and select the basic geographic information element layer to be converted;

[0064] (3) Setting tool parameters, mainly including setting the target CRS to "China Geodetic CoordinateSystem 2000", dynamically adjusting the coordinate system transformation mode with the source coordinate system and the target coordinate system, and setting the projection output path;

[0065] (4) Run the tool to complete the coordinate system conversion of basic geographic information elements; Figure 3 A schematic diagram of a coordinate system conversion tool according to an embodiment of the present invention is shown.

[0066] S2-2: supplement the point, line and surface elements in the multi-level geographic information element database according to the requirements of the expression granularity of geographic entities; revise the element objects in the multi-level geographic information element database according to the expression requirements of the geometric objects of geographic entities;

[0067] Combination Figure 4 As shown, an example of supplementary collection of building outer contour surface elements in an embodiment of the present invention is as follows:

[0068] (1) Prioritize the use of natural building data (ZRZ) in the real estate registration survey data, extract the surface plot building (natural building) graphics according to the "plot code" class attribute, and analyze whether the real estate registration survey data meets the current requirements. If it does, refer to the natural building graphics and merge the house surfaces in DLG (houses in construction will not be merged with other types of houses, and destroyed houses will not be included in the merger).

[0069] (2) When the real estate title survey data is not covered or the current situation does not meet the requirements, refer to the standard address database, disaster comprehensive risk survey data and other reference materials to merge the house surfaces in the DLG (reference priority: disaster comprehensive risk survey data > standard address database)

[0070] S2-3, based on the existing DLG data, automatically derive the target ground object as the geometric compensation of the geographic entity graphic data; for example, the width attribute item of the road is used as one of the weight values, and the road traffic intersection object is automatically extracted at the intersection of the road line and surface topology;

[0071] S2-4, perform connectivity processing on spatial geometric objects with continuity characteristics, such as roads and water system objects;

[0072] Optionally, the road object connectivity processing example is as follows:

[0073] (1) Urban road (main, secondary, branch, special, etc.) surfaces are supplemented with surface graphics at road intersections based on the principle of connecting named roads to ensure that named roads are connected to each other; if a named road intersects with an unnamed road, the integrity and connectivity of the named road surface shall be guaranteed first;

[0074] (2) Regardless of whether the highways (national, provincial, county, township, etc.) have names or not, the intersections shall be processed with surface graphics to ensure that they are connected;

[0075] (2) Based on the connected urban roads and highway surfaces, the corresponding urban road lines are corrected. The road lines and road surfaces follow the one-to-one correspondence principle and run through the road surfaces and intersection surfaces. If there are other roads at the end of the road, the end point of the road line must be on another road line, that is, no hanging points are allowed at the end points.

[0076] S2-5, storing the attribute value mapping dictionary in the format of <original attribute content, current attribute content>, and completing the entity processing of the attribute value of the geographic information element;

[0077] S2-6, consistency processing of topological relationships within and between layers of each geographic information element.

[0078] S3, performing data quality inspection based on the objectified results library; the data quality inspection includes representation quality inspection, element connectivity inspection, attribute consistency inspection, geometric validity inspection and topological consistency inspection.

[0079] S4, based on the object-based results library that has passed the quality inspection, analyze the relationship between geographic information elements and geographic entities; specifically: based on the object-based results library that has passed the quality inspection, analyze the relationship between geographic information elements and geographic entities from the aspects of the data's spatiotemporal characteristics, attribute characteristics, spatial relationship characteristics, etc., including geometric correspondence and the relationship between attribute fields and value domains.

[0080] S5, constructing mapping rules between geographic information elements and geographic entities based on the association relationship between the geographic information elements and the geographic entities; including classification code mapping rules, geometric information mapping rules, and attribute information mapping rules.

[0081] The classification code mapping rules include one-to-one mapping, one-to-many mapping, many-to-many mapping, and many-to-one mapping; the attribute content mapping rules include direct mapping, combination mapping, translation mapping, and default value filling; the geometric object mapping rules include single-element mapping, multi-element combination mapping, and multi-element fusion.

[0082] S6, storing the mapping rules in a file in a structured data format to form a standard production specification for geographic entities.

[0083] S7, performs geometric extraction conversion and attribute mapping based on geographic entity standard production specifications to obtain an intermediate entity library.

[0084] The intermediate entity library is a GDB database organized in layers of standard entity result libraries. The GDB library mainly includes two parts: temporary feature metadata and temporary entity data. The feature layer name and feature layer attribute structure of the temporary feature are consistent with the standard feature result structure specified in the production specification; the entity layer name and entity layer attribute structure of the temporary entity are consistent with the standard entity result structure specified in the production specification. The intermediate entity library is an intermediate result in the production process of converting basic geographic information elements into geographic entity results. Based on the mapping conversion scheme, multi-source geographic information feature data with different structures can be standardized through operations such as geometry extraction and attribute conversion, and the processing results can be stored in the temporary feature of the intermediate entity library to facilitate the subsequent establishment of entities based on entity construction rules. Figures 5a to 5d shown.

[0085] S8, according to the content requirements of various entities, build operators based on system entities to customize the entity production plan, fuse and combine graphics elements, build single-element, multi-element entities and combined entities, etc.

[0086] The embodiment of the present invention also provides a system for executing the method of constructing geographic entities based on DLG topographic maps described in the above embodiment, the system is based on the QT framework and is constructed in combination with the geometric algorithm library of GDAL and GEOS. The system includes a data processing module, a specification management module, an entity production module, and a quality inspection module.

[0087] The method for constructing geographic entities based on DLG topographic maps in an embodiment of the present invention solves the problems of difficult quality control and data mapping conversion solution management in the objectification processing of geographic information elements, reduces the workload of manual intervention in the production process of geographic entities, and improves the degree of automation of data processing and entity construction in the production process; in response to the phenomenon of diversified geographic entity construction methods, a series of entity construction operators based on multi-spatial relationship and multi-attribute relationship constraints are developed, which greatly meets the personalized needs of geographic entity production at multiple scales and realizes the rapid construction and output of standardized geographic entity results.

[0088] Figure 6 is a schematic diagram of the overall scheme of a method for constructing geographic entities based on a DLG topographic map according to another embodiment of the present invention, Figure 3 It can be seen that the method for constructing a geographic entity based on a DLG topographic map in an embodiment of the present invention may include:

[0089] Step 401: input the DLG topographic map data to be converted into the system; after acquiring the DLG topographic map data, execute steps 402 to 407 to objectify the DLG topographic map and obtain an objectified result library.

[0090] Step 402: coordinate conversion and projection conversion processing are performed on the input topographic map elements. This step requires setting three parameters, including the target CRS, the coordinate system conversion method, and the projection output path (the specific process can be referred to the record of the above step S2-1).

[0091] Step 403: Graphically edit and geometrically supplement the coordinate transformation result data. This step requires geometric editing and shaping to ensure that the expression form of geographic information elements is consistent with the requirements of the geographic entity results. For example, in response to the requirement in the 1:2000 geographic entity results that highways and urban road entities are expressed as surface elements, the structural line data such as road sidelines and center lines can be input into the system to construct the road surface through parametric mapping.

[0092] Step 404: The system performs connectivity processing on the results of graphic editing and geometric supplementation based on the data processing module of the system. The system traverses each feature object in the feature layer, analyzes the spatial relationship and attribute consistency between the features, and connects the feature objects that meet the connectivity parameter threshold (distance threshold, attribute merging item) to ensure the correctness of the expression of geographic information elements.

[0093] Step 405: Edit and supplement the attribute information according to the graphic processing result outputted in step 404. Supplement the geographic information business attributes and other information, such as the attribute of the national highway entity width, based on the table connection and geometric information automatic extraction functions of the system data processing module.

[0094] Step 406: Based on the attribute mapping dictionary, complete the entity processing of the attribute value of the geographic information element. This step requires the configuration of a structured mapping dictionary file, and the attribute value of the DLG topographic map is converted into the attribute information of the corresponding entity class through the attribute value calculation function. The figure below shows the attribute mapping dictionary for converting the feature classification code to the data type.

[0095] An example of updating the mapping dictionary of geographic information feature attributes is shown in the following code:

[0096]

[0097] Step 407: Perform topological consistency processing based on the result of attribute mapping update in step 406. Comply with the requirements of the geometric topological relationship of geographic entities, correct the spatial relationship between elements, ensure that there are no illegal gaps, overlaps, invalid geometry errors within and between data layers, and output the object-oriented results library.

[0098] Step 408: Perform data check based on the objectified achievement library obtained in step 407;

[0099] Table 1 Object-oriented quality inspection content

[0100]

[0101]

[0102] Step 409, Step 410: Analyze the basic characteristics of the data in the objectified results database, determine the source of the graphic elements and attribute information of various geographic entities, determine the one-to-one unidirectional mapping relationship between each element of the objectified library and the geographic entity through attribute filtering, and construct classification code mapping rules, geometric information mapping rules, and attribute information mapping rules.

[0103] In the embodiment of the present invention, the basic characteristics of the data in the objectified achievement database can be analyzed to determine whether there is a relationship between the geometry, attributes, and other contents of the objectified achievement database data and the geographic entities from aspects such as timeliness, content consistency, and geometric consistency. Based on the analysis results, a mapping table of primitive and entity attribute information is produced, and finally the construction of classification code mapping rules, geometric information mapping rules, and attribute information mapping rules is completed. Taking transportation as an example, it is analyzed which attribute fields in the original objectified data layer can be used as the source of attribute information of the achievement data and the mapping relationship between the fields, and the attribute mapping table is summarized.

[0104] Table 2 Attribute mapping table meaning

[0105]

[0106] Step 411: Based on the mapping rules constructed in steps 409 and 410, a data extraction and conversion plan is written and stored in the mdb in the form of a structured data table. Figure 7 This is a schematic diagram of the data extraction and conversion solution mdb according to an embodiment of the present invention.

[0107] Table 3-1 Geographic entity specification table structure

[0108]

[0109]

[0110] Table 3-2 Geographic entity specification table structure (continued from Table 3-1)

[0111]

[0112]

[0113] Step 412: The system reads the geographic entity specification constructed in step 411, converts and extracts the objectified results library that has been input into the system into an intermediate entity library stored in the standard structure of geographic entities according to the mapping scheme specified in the production specification, and obtains and stores the basic graphic element information and attribute information of various geographic entities.

[0114] Step 413: Based on the existing entity construction operators of the system, various entity construction rules are configured. The system reads the entity construction rule json file, and various graphic elements in the intermediate entity library are combined or merged through multi-attribute filtering, multi-spatial relationship filtering and combination constraints to generate single-graphic entity, multi-graphic entity or combined entity, and finally complete the entity construction and output the standardized entity results library.

[0115] Figure 8 and Fig. 9 A Json schematic diagram of the construction rules of a national highway entity and a Json schematic diagram of the construction rules of a river entity in an embodiment of the present invention are respectively shown.

[0116] Combination Figure 8 It can be seen that the construction process of the construction rules of the national highway entity can be as follows:

[0117] (1) Obtain the line map metadata used to construct the national highway entity through the data filter. The filtering rule is: "(CLASSID = '220201' OR ROADCODE LIKE '%G%' OR ROADCODE2 LIKE '%G%' OR ROADCODE3 LIKE '%G%' OR ROADCODE4 LIKE '%G%') AND CLASSID NOT LIKE '220301'";

[0118] (2) Obtain the line map metadata used to construct the national highway entity through the data filter. The filtering rule is: "(ROADCODE LIKE'%G%' AND CLASSID NOT LIKE'221302') AND CLASSID NOT LIKE'220301'";

[0119] (3) Obtain the line map metadata used to construct the national highway entity through the data filter, and the filtering rule is: "ROADCODE LIKE'%G%'AND CLASSID LIKE'221302'";

[0120] (4) Based on the "Multi-layer Line Through Construction" operator, the obtained national highway line primitives are combined, and the filtering rule is: "'Contains G'AND'ROROADCODE,ROADCODE2,ROADCODE3,ROADCODE4 have equal values'";

[0121] (5) Based on the "plane intersection line construction" operator, the national highway section surface and the line set obtained after the combination in step (4) are combined according to the "plane intersection line" mode;

[0122] (6) Based on the "face intersection line construction" operator, the national highway intersection face and the primitive set formed by the face and line combination in step (5) are combined again according to the "face intersection line" mode to finally obtain the national highway entity.

[0123] Table 4 Geographic entity construction operator table structure in the system

[0124]

[0125]

[0126]

[0127] An embodiment of the present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store program codes, and the program codes are used to execute the method for constructing geographic entities based on a DLG topographic map as described in the above embodiment.

[0128] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for constructing geographic entities based on DLG topographic maps, characterized in that: The method comprises: Collect DLG topographic maps for making geographic entities; Performing object-oriented processing on the DLG topographic map to obtain an object-oriented result library; Performing data quality inspection based on the objectified results library; Analyze the relationship between geographic information elements and geographic entities based on the object-oriented results library that has passed quality inspection; Constructing a mapping rule between geographic information elements and geographic entities based on the association relationship between the geographic information elements and the geographic entities; Storing the mapping rules in a file in a structured data format to form a standard production specification for geographic entities; Perform geometric extraction conversion and attribute mapping based on geographic entity standard production specifications to obtain an intermediate entity library; According to the content requirements of various entities, operators are built based on system entities to customize the entity production plan.

2. The method according to claim 1, characterized in that The object-oriented processing of the DLG topographic map to obtain an object-oriented result library comprises: Based on the results requirements of geographic entities, convert the coordinate system of geographic information element data; According to the requirements of geographic entity expression granularity, the point, line and surface elements in the multi-level geographic information element database are supplemented; according to the requirements of the expression of geographic entity geometric objects, the element objects in the multi-level geographic information element database are modified; Based on the existing DLG data, the target ground object is automatically derived as the geometric compensation of the geographic entity graphic data; Process the connectivity of spatial geometric objects with continuity characteristics; The attribute value mapping dictionary is stored in the format of <original attribute content, current attribute content> to complete the entity processing of the attribute value of the geographic information element; Consistency processing of topological relationships within and between layers of each geographic information element.

3. The method according to claim 1, characterized in that The data quality inspection includes representation quality inspection, feature connectivity inspection, attribute consistency inspection, geometric validity inspection and topological consistency inspection.

4. The method according to claim 1, characterized in that: The analysis of the relationship between geographic information elements and geographic entities based on the object-oriented results library that has passed the quality inspection includes: Based on the objectified results library that has passed quality inspection, the relationship between geographic information elements and geographic entities is analyzed from the aspects of the data's spatiotemporal characteristics, attribute characteristics, spatial relationship characteristics, etc., including geometric correspondence and the relationship between attribute fields and value domains.

5. The method according to claim 1, characterized in that The mapping rules between the geographic information elements and the geographic entities include: classification code mapping rules, attribute content mapping rules, and geometric object mapping rules; The classification code mapping rules include one-to-one mapping, one-to-many mapping, many-to-many mapping, and many-to-one mapping; Attribute content mapping rules include direct mapping, combined mapping, translation mapping, and default value filling; Geometric object mapping rules include single-element mapping, multi-element combination mapping, and multi-element fusion.

6. The method according to claim 1, characterized in that Entity construction operators include: Single-element construction: Filter elements based on the attributes of SQL statements, and each entity is composed of a single element; Single layer line intersection construction: within the same layer, when lines intersect at one or more points in space, line features are combined or fused to construct; Single layer line penetration construction: When the lines intersect at one point in the internal space of the same layer and the point type is an endpoint, the line features are combined or fused to construct; Single layer line first-line connection construction: When the lines intersect at one point in the internal space of the same layer, and the point type must be the starting point of one line and the end point of another line element, the line elements are combined or fused to construct; Multi-layer line intersection construction: When multiple layers intersect at one or more points in space, line features are combined or fused to construct; Multi-layer line construction: When multiple layers intersect at one point in space and the point type is endpoint, line features are combined or fused to construct; Multi-layer line first-line connection construction: When multiple layers intersect at one point in space, and the point type must be the starting point of one line and the end point of another line feature, the line features are combined or fused to construct; Line intersection surface construction: take the line as the selection element and the surface object as the target element, set the reuse of the primitives, and combine the line and surface elements that meet the intersection relationship to construct an entity; Constructing intersecting lines: Use lines as selection elements and surface objects as target elements. Set the threshold of the length ratio of lines within the surface and the reuse of primitives. Combine line and surface elements that meet the intersection relationship to construct entities. Common attribute construction: When the specified field values ​​have a value inclusion relationship between multiple graphs, they are combined or fused to support setting attribute constraints, null value constraints, etc. Each entity has two or more graphic elements; Area inclusion construction: Use the area as the selection element, point, line, and area objects as the target elements, set the reuse of the primitives, and combine the point, line, and area elements that meet the full inclusion relationship to construct an entity; Buffer construction: Within the same layer, each element sets a buffer based on parameters. When other elements exist in the buffer, the two elements are combined or fused to construct.

7. A system for executing the method for constructing geographic entities based on a DLG topographic map as claimed in any one of claims 1 to 6, characterized in that: The system is constructed based on the QT framework and combined with the geometric algorithm libraries of GDAL and GEOS.

8. The system according to claim 7, characterized in that The system includes a data processing module, a standard management module, a physical production module, and a quality inspection module.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program codes, and the program codes are used to execute the method for constructing geographic entities based on a DLG topographic map as described in any one of claims 1 to 8.

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