Regional target representation method and device based on global discrete grid

Abstract

The present invention provides a method and device for characterizing regional targets based on global discrete grids, and relates to the technical field of global discrete grids. The method includes: when the regional target to be characterized is a circular regional target, based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and a preset grid level, three first grid codes for identifying the circular regional target are determined; when the regional target to be characterized is a polygonal regional target, vertices of the polygonal region of the polygonal regional target are extracted to obtain a plurality of extracted target vertices, and based on the longitude and latitude of the plurality of target vertices and a preset grid level, a second grid code at the plurality of target vertices is determined. The present invention can reduce the number of grid codes for identifying regional targets, reduce the amount of data storage and transmission data of the device, and thereby improve the grid code transmission efficiency of the device.

Description

Technical Field

[0001] The present invention relates to the technical field of global discrete grids, and in particular to a method and device for characterizing regional targets based on global discrete grids. Background Art

[0002] The global discrete grid system is a globe-fitting grid based on the sphere that can be infinitely subdivided without changing its shape. When subdivided to a certain extent, it can simulate the earth's surface. It is expected to fundamentally solve the problems of data discontinuity, geometric deformation and topological inconsistency in plane models in global space management and multi-scale operations. It can provide a continuous, globally unified analysis framework for remote sensing satellite scheduling management, drone route planning, weather forecasting and other fields.

[0003] Considering the need to respond quickly and handle large-scale tasks, it is particularly important to conduct in-depth analysis of multi-target repeated observation tasks. In this scenario, there is a complex coupling relationship between tasks. Therefore, in order to ensure maximum coverage of regional targets and perform as many repeated observation tasks as possible within a limited computing time, the task set must be clustered to improve planning efficiency. The core concept of task clustering is to classify similar observation tasks together, thereby reducing duplicate observations and optimizing observation plans. By combining similar tasks together, conflicts between tasks can be reduced and task execution efficiency can be improved. This task clustering method helps to cover as many ground targets as possible within a limited time.

[0004] Traditional clustering-based target mission planning algorithms usually aggregate tasks based on factors such as target coordinates, distance, and the satellite's roll angle. However, this method requires a large number of floating-point calculations in Euclidean space, which affects the processing efficiency of mission planning. In contrast, the global discrete grid system has a global multi-resolution and multi-level topological structure, which can directly use efficient coding calculation operations to achieve the aggregation of target grid tasks. The advantage of this system is that it can divide the earth's surface into grids, each of which has a unique identifier, without the need for complex floating-point calculations. By using a global discrete grid system, the response speed of satellite mission planning has been significantly improved. Therefore, it is necessary to characterize regional targets based on a global discrete grid system.

[0005] At present, for circular area targets, a polygonal area similar to the circular area target is generated based on the longitude and latitude of the circular area target and the radius of the circular area target, and then all the grids covered by the polygonal area are obtained using the polygon-to-grid method of the global discrete grid system, so as to characterize the circular area target based on the codes of all the grids. However, characterizing the circular area target based on the codes of all the grids covered by the polygonal area results in a large amount of grid code storage and transmission data for characterizing the target, which in turn reduces the efficiency of grid code information transmission of the circular area target.

[0006] At present, for polygonal area targets, the polygon-to-grid method of the global discrete grid system is used to obtain all the grids covered by the polygonal area of ​​the polygonal area target, so as to characterize the polygonal area target based on the coding of all the grids. However, characterizing the polygonal area target based on the coding of all the grids covered by the polygonal area leads to a large amount of grid coding storage and transmission data for characterizing the target, which in turn reduces the efficiency of grid coding information transmission for circular area targets. Summary of the invention

[0007] The present invention provides a method and device for regional target characterization based on global discrete grid, which are used to solve the defects of large data storage volume and large data transmission volume in the prior art.

[0008] The present invention provides a regional target characterization method based on a global discrete grid, comprising:

[0009] In the case where the area target to be characterized is a circular area target, three first grid codes for identifying the circular area target are determined based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level; the central longitude and latitude are the longitude and latitude of the center position of the circular area target, any of the first grid codes is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular area target;

[0010] In the case where the area target to be characterized is a polygonal area target, extracting vertices from the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, and determining second grid codes at the plurality of target vertices based on the latitude and longitude of the plurality of target vertices and a preset grid level; the second grid code at any of the target vertices is a code of a polygonal grid covering the target vertex, and the grid codes at the plurality of target vertices are used to identify the polygonal area target;

[0011] The mesh level is used to represent the size of a polygonal mesh.

[0012] According to a method for characterizing an area target based on a global discrete grid provided by the present invention, the method determines three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level, including:

[0013] Based on the physical radius of the circular area target and the preset grid level, determine the number of first grids that the circular area target needs to cover within its radius area;

[0014] The grid where the central longitude and latitude of the circular area target are located is taken as the first central grid, and based on the first central grid and the first grid quantity, three first grid codes for identifying the circular area target are determined.

[0015] According to a method for characterizing a regional target based on a global discrete grid provided by the present invention, the method determines the number of first grids that the circular regional target needs to cover within its radius area based on the physical radius of the circular regional target and a preset grid level, including:

[0016] Based on the physical radius of the circular area target, determining the target radius of the circular area target in the global discrete grid system;

[0017] The central longitude and latitude of the circular area target is used as the central position of the first central grid, and the number of first grids that the circular area target needs to cover within its radius area is determined based on the target radius and the grid level.

[0018] According to a method for characterizing a regional target based on a global discrete grid provided by the present invention, the method of determining three first grid codes for identifying the circular regional target based on the first central grid and the first number of grids includes:

[0019] Taking the central longitude and latitude of the circular area target as the origin of the three-axis coordinate system, and constructing the three-axis coordinate system on the circular area of ​​the circular area target;

[0020] Taking the first central grid as the center, determining a target polygonal grid in three coordinate axis directions of the three-axis coordinate system based on the first grid quantity;

[0021] A first mesh code for identifying the three target polygonal meshes of the circular area target is generated.

[0022] According to a method for characterizing an area target based on a global discrete grid provided by the present invention, after determining three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level, the method further includes:

[0023] Taking the central longitude and latitude of the circular area target as the rotation center point, the three target polygonal meshes are respectively rotated by 60 degrees to obtain three rotated polygonal meshes;

[0024] Selecting one vertex from each of the three target polygonal meshes and the three rotated polygonal meshes respectively to obtain six first vertices;

[0025] The six first vertices are connected in sequence to obtain a first characteristic hexagon covering the circular area of ​​the circular area target.

[0026] According to a method for characterizing a regional target based on a global discrete grid provided by the present invention, the step of selecting a vertex of each of the three target polygonal grids and the three rotated polygonal grids to obtain six first vertices includes:

[0027] Based on the rotation center point, select one vertex of each of the three target polygonal meshes and the three rotated polygonal meshes to obtain six first vertices;

[0028] Among them, the distance between the first vertex of any polygonal mesh and the rotation center point is greater than the distance between other vertices of the polygonal mesh except the first vertex and the rotation center point, so that the first characteristic hexagon completely covers the circular area of ​​the circular area target.

[0029] According to a method for characterizing a regional target based on a global discrete grid provided by the present invention, after sequentially connecting the six first vertices to obtain a first characteristic hexagon of a circular area covering the circular regional target, the method further includes:

[0030] The grid where the central longitude and latitude of the circular area target is located is taken as the first central grid, and the position where the central longitude and latitude of the circular area target is located is taken as the center position of the first central grid, and the number of second grids required to be covered in the area from any vertex of the first characteristic hexagon to the center position of the first central grid is determined; the number of the second grids is N;

[0031] Based on the second number of grids, grids are expanded outward on the basis of the first central grid to obtain multiple first extended grids; the second number of grids is used to indicate that the expansion stops after N-1 first extended grids are expanded outward in one direction;

[0032] A union of the first central grid and the plurality of first extended grids is used as a grid set of the first characteristic hexagon.

[0033] According to a method for representing a regional target based on a global discrete grid provided by the present invention, extracting vertices from a polygonal region of the polygonal regional target to obtain a plurality of extracted target vertices includes:

[0034] Based on the grid level, vertex extraction is performed on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, so that a polygonal mesh represented by the grid level only covers one vertex at any boundary position of the polygonal area.

[0035] According to a method for characterizing a regional target based on a global discrete grid provided by the present invention, after determining the second grid codes at the multiple target vertices based on the longitudes and latitudes of the multiple target vertices and the preset grid level, the method further includes:

[0036] Based on the multiple target vertices, determining a center position of a target polygonal area formed by the multiple target vertices;

[0037] Based on the center position of the target polygonal area, a vertex of the polygonal meshes corresponding to the plurality of second mesh codes is respectively selected to obtain a plurality of second vertices; the distance between the second vertex of the polygonal mesh corresponding to any of the second mesh codes and the center position of the target polygonal area is greater than the distance between the other vertices of the polygonal mesh corresponding to the second mesh code except the second vertex and the center position of the target polygonal area;

[0038] The plurality of second vertices are connected in sequence to obtain a second characteristic hexagon that completely covers the target polygonal area.

[0039] According to a method for representing a regional target based on a global discrete grid provided by the present invention, after sequentially connecting the plurality of second vertices to obtain a second characteristic hexagon that completely covers the target polygonal area, the method further includes:

[0040] The grid where the center position of the target polygonal area is located is used as the second center grid;

[0041] Based on the second characteristic hexagon and the preset expansion requirement, a grid is expanded outwardly on the basis of the second central grid to obtain a plurality of second extended grids; the preset expansion requirement is used to indicate that the second extended grid obtained by expanding outwardly in one direction stops expanding when it reaches the boundary of the second characteristic hexagon, and the preset expansion requirement is used to make the second central grid and the plurality of second extended grids completely cover the second characteristic hexagon together;

[0042] A union of the second central grid and the plurality of second extended grids is used as a grid set of the second characteristic hexagon.

[0043] The present invention also provides a regional target characterization device based on a global discrete grid, comprising:

[0044] A first determination module is used to determine, when the area target to be characterized is a circular area target, three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level; the central longitude and latitude are the longitude and latitude of the center position of the circular area target, any of the first grid codes is a code of a target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular area target;

[0045] A second determination module is used for, when the area target to be characterized is a polygonal area target, extracting vertices from the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, and determining second grid codes at the plurality of target vertices based on the longitude and latitude of the plurality of target vertices and a preset grid level; the second grid code at any of the target vertices is a code of a polygonal grid covering the target vertex, and the grid codes at the plurality of target vertices are used to identify the polygonal area target;

[0046] The mesh level is used to represent the size of a polygonal mesh.

[0047] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for characterizing regional targets based on a global discrete grid as described above is implemented.

[0048] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the above-described regional target characterization methods based on a global discrete grid.

[0049] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned regional target characterization methods based on global discrete grids.

[0050] The regional target characterization method and device based on global discrete grids provided by the present invention, when the regional target to be characterized is a circular regional target, based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and the preset grid level, three first grid codes for identifying the circular regional target are determined, and the central longitude and latitude are the longitude and latitude of the central position of the circular regional target, and any first grid code is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular regional target, so that only the first grid codes of the three target polygonal grids covering a partial circular boundary of the circular regional target are needed to characterize the circular regional target, and there is no need to characterize the circular regional target based on the grid codes of all grids covered by the polygonal area, that is, the three first grid codes can represent all grid codes within the circular area of ​​the circular regional target, thereby reducing the data storage amount and the transmission data amount of the device, thereby improving the grid coding efficiency of the device. The code transmission efficiency is improved, and finally the regional target characterization method is executed on limited hardware devices; at the same time, when the regional target to be characterized is a polygonal regional target, vertices of the polygonal area of ​​the polygonal area target are extracted to obtain multiple target vertices after extraction, and the second grid codes at the multiple target vertices are determined based on the longitude and latitude of the multiple target vertices and the preset grid level, and the second grid code at any target vertex is the code of the polygonal grid covering the target vertex, and the grid codes at the multiple target vertices are used to identify the polygonal area target, so that only the second grid code of some vertices of the polygonal area covering the polygonal area target is needed to characterize the polygonal area target, and there is no need to characterize the polygonal area target based on the grid codes of all grids covered by the polygonal area, thereby reducing the data storage amount and transmission data amount of the device, improving the grid code transmission efficiency of the device, and finally ensuring the execution of the regional target characterization method on limited hardware devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0052] Figure 1 It is one of the flow charts of the regional target characterization method based on global discrete grid provided by the present invention.

[0053] Figure 2It is a simplified process schematic diagram of the polygonal area provided by the present invention.

[0054] Figure 3 It is a schematic diagram of the polygonal area target and the identification grid provided by the present invention.

[0055] Figure 4 It is a schematic diagram of the circular area target and the identification grid provided by the present invention.

[0056] Figure 5 This is the second flow chart of the regional target characterization method based on the global discrete grid provided by the present invention.

[0057] Figure 6 It is a schematic diagram of the rotation grid and characteristic hexagon provided by the present invention.

[0058] Figure 7 This is the third flow chart of the regional target characterization method based on global discrete grid provided by the present invention.

[0059] Figure 8 It is a schematic diagram of a grid unit set of a circular area target provided by the present invention.

[0060] Fig. 9 This is the fourth flow chart of the regional target characterization method based on the global discrete grid provided by the present invention.

[0061] Fig.10 It is a schematic diagram of the identification grid and characteristic hexagons provided by the present invention.

[0062] Fig.11 This is the fifth flow chart of the regional target characterization method based on global discrete grid provided by the present invention.

[0063] Fig.12 It is a schematic diagram of a grid unit set of a polygonal area target provided by the present invention.

[0064] Fig.13 It is a structural schematic diagram of a regional target characterization device based on a global discrete grid provided by the present invention.

[0065] Fig.14 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] The global discrete grid system is a spherical body fitting grid that can be infinitely subdivided without changing its shape. When subdivided to a certain extent, it can achieve the purpose of simulating the surface of the earth. It is expected to fundamentally solve the problems of data breakage, geometric deformation and topological inconsistency in the global space management and multi-scale operation of the plane model. It can provide a continuous and globally unified analysis framework for remote sensing satellite scheduling management, drone route planning, weather forecasting and other fields. And theoretical progress has been made in many fields, such as the online car-hailing planning and scheduling method based on H3 grid, the drone planning and low-altitude management method based on three-dimensional grid, the satellite observation capability visualization algorithm based on HEALPix quadrilateral grid, and the time window calculation and satellite resource integrated management algorithm based on GeoSOT national grid.

[0068] In other words, as a spatial identification method with a limited number of units, the global discrete grid can effectively solve the current problems faced in many fields that require geographic information analysis. Using limited grid codes instead of traditional unlimited longitude and latitude coordinates can not only greatly reduce the complexity of the problem, but also make full use of data resources to meet user needs. The global discrete grid plays an important role in the process of expressing geographic spatial objects. Using grid codes to represent the regional scope of the target is conducive to subsequent analysis and calculation based on the global discrete grid, improving the efficiency of geographic information processing, and ensuring that the user's requirements for response time are met.

[0069] The global discrete grid system not only has significant advantages in the division of the spherical surface in various application fields, but also can perform grid management of various types of regional targets.

[0070] For example, the management of aerial photography drone mission targets based on the global discrete grid system. Aerial photography drones play a vital role in the fields of agricultural insurance, forest fire fighting, emergency rescue, and military reconnaissance. In most application scenarios, the targets that need to be photographed are often scattered in different regional locations. Reasonable and scientific management of these regional targets is conducive to improving shooting efficiency and improving shooting effects. The global discrete grid can cover the world approximately evenly, has a variable scaling scale, and has a limited number of grid units at any subdivision level. It can limit the complexity of the planning problem and speed up the response speed of drone planning. Therefore, using the global discrete grid for regional target management of aerial photography drone missions is a scientific and effective idea.

[0071] Another example is the regional target management of agile earth observation satellites based on the global discrete grid system. Earth observation satellites are usually in low-Earth orbit and use onboard sensors to perform tasks. However, due to the limitation of the sensor's field of view, satellites can only observe targets within a limited range at a certain moment. Traditional non-agile satellites can only expand their visual range through attitude maneuvers of the roll axis. Agile satellites have more flexible pitch and roll dual-axis maneuvering capabilities, enabling them to observe before or after passing the top. This capability enables agile satellites to perform imaging tasks in multiple modes, such as multi-angle stereo imaging and regional target mosaic imaging, thereby expanding the application field of earth observation satellites. However, the emergence of agile satellites has also increased the complexity of mission planning problems. When faced with large-scale tasks, the difficulty of mission planning increases dramatically, resulting in excessively long planning time, especially when computing resources are limited and mission response time requirements are high, which makes it difficult to meet user needs.

[0072] Considering the need to respond quickly and handle large-scale tasks, it is particularly important to conduct in-depth analysis of multi-target repeated observation tasks. In this scenario, there is a complex coupling relationship between tasks. Therefore, in order to ensure maximum coverage of regional targets and perform as many repeated observation tasks as possible within a limited computing time, the task set must be clustered to improve planning efficiency. The core concept of task clustering is to classify similar observation tasks together, thereby reducing duplicate observations and optimizing observation plans. By combining similar tasks together, conflicts between tasks can be reduced and task execution efficiency can be improved. This task clustering method helps to cover as many ground targets as possible within a limited time.

[0073] Traditional clustering-based target mission planning algorithms usually aggregate tasks based on factors such as target coordinates, distance, and the satellite's roll angle. However, this method requires a large number of floating-point calculations in Euclidean space, which affects the processing efficiency of mission planning. In contrast, the global discrete grid system has a global multi-resolution and multi-level topological structure, which can directly use efficient coding calculation operations to achieve the aggregation of target grid tasks. The advantage of this system is that it can divide the earth's surface into grids, each of which has a unique identifier, without the need for complex floating-point calculations. By using a global discrete grid system, the response speed of satellite mission planning has been significantly improved. Therefore, it is necessary to characterize regional targets based on a global discrete grid system.

[0074] In other words, under the influence of the dual trends of the rapid growth of earth observation data and the continuous expansion of geographic information analysis needs, the traditional geographic information analysis method based on longitude and latitude is no longer sufficient to cope with today's increasingly complex surface environment and the continuously increasing demand in many application fields. The traditional analysis and calculation method based on longitude and latitude requires frequent calculation of the ground coverage of each regional target, and the calculation results are stored, transmitted and calculated in the form of longitude and latitude arrays. The longitude and latitude data itself is a floating point type, which will take up more resources during storage, transmission and calculation. Today's spatial information acquisition technology is developing rapidly. The traditional complex calculation method superimposed on the rapidly expanding number of ground targets has increased the difficulty of geographic information analysis, and it also makes it difficult to effectively meet the increasing needs of users for geographic information analysis.

[0075] At present, for circular area targets, which are important regional target forms in many application fields, a polygonal area similar to the circular area target is generated based on the longitude and latitude of the circular area target and the radius of the circular area target, and then all the grids covered by the polygonal area are obtained using the polygon-to-grid method of the global discrete grid system, so as to characterize the circular area target based on the coding of all the grids. However, characterizing the circular area target based on the coding of all the grids covered by the polygonal area results in a large amount of grid coding storage and transmission data for characterizing the target, thereby reducing the efficiency of grid coding information transmission of the circular area target.

[0076] At present, for polygonal area targets, the polygon-to-grid method of the global discrete grid system is used to obtain all the grids covered by the polygonal area of ​​the polygonal area target, so as to characterize the polygonal area target based on the coding of all the grids. However, characterizing the polygonal area target based on the coding of all the grids covered by the polygonal area leads to a large amount of grid coding storage and transmission data for characterizing the target, which in turn reduces the efficiency of grid coding information transmission for circular area targets.

[0077] That is, it mainly converts the regional target in the form of longitude and latitude array into a large number of grid codes in the region, so that the grid codes can be used for subsequent analysis and calculation. Although this method can realize the gridding of regional targets, when the grid division level is high or the regional target is large, the number of grids in the regional target is too large, and the storage space required for the corresponding grid code and the amount of data during transmission will also be too large, which will cause unnecessary burden in the actual analysis and calculation process. In addition, the storage and computing resources of hardware devices are limited, and too many grid codes are difficult to adapt to the general hardware environment, which is not conducive to efficient computing and analysis.

[0078] In view of the above problems, the present invention proposes the following embodiments. Figure 1-Figure 12 The present invention describes a regional target characterization method based on a global discrete grid.

[0079] Figure 1 is one of the flow charts of the regional target characterization method based on global discrete grid provided by the present invention, such as Figure 1 As shown, the regional target characterization method based on the global discrete grid includes the following steps 110 and 120.

[0080] Step 110, when the area target to be characterized is a circular area target, three first grid codes for identifying the circular area target are determined based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level.

[0081] The embodiments of the present invention can be applied to the fields of online car-hailing planning and scheduling, drone planning and low-altitude management, satellite observation capability visualization, integrated satellite resource management, aerial photography drone mission target management, and earth observation agile satellite regional target management, etc.

[0082] Here, the area target to be characterized is an area target to be characterized (identified) by grid coding. The area target to be characterized may be a circular area target or a polygonal area target (any area target, non-circular area target).

[0083] Here, the target area of ​​the circular area target is a circular area, that is, the boundary of the target area is a circular boundary.

[0084] The central longitude and latitude are the longitude and latitude of the center position of the circular area target, that is, the central longitude and latitude are the longitude and latitude of the center position of the circular area of ​​the circular area target.

[0085] Here, the physical radius of the circular area target is the radius of the circular area of ​​the circular area target, and the physical radius may be a radius in the real physical world.

[0086] The mesh level (mesh subdivision level) is used to characterize the size of a polygonal mesh. The mesh fineness can be determined based on the mesh level. The higher the mesh level, the smaller the corresponding polygonal mesh and the higher the precision. The lower the mesh level, the larger the corresponding polygonal mesh and the lower the precision.

[0087] The grid level may be input by a user, that is, the grid division level is determined by the user.

[0088] The area of ​​each polygonal grid of the global discrete grid system of the embodiment of the present invention is the same, that is, the area of ​​the grid unit is relatively uniform. The polygonal grid can be a hexagonal grid, an octagonal grid, a quadrilateral grid, etc. The embodiment of the present invention is described by taking a hexagonal grid as an example, for example, taking a hexagonal grid with a relatively uniform grid unit area as an example, and further taking a spherical icosahedral hexagonal grid with a relatively uniform grid unit area as an example. Further, the hexagonal grid can be a regular hexagonal grid.

[0089] Among them, any of the first mesh codes is a code of a target polygonal mesh, and the target polygonal mesh is a mesh covering a portion of the circular boundary of the circular area target.

[0090] It should be noted that, since three points on the circular boundary can determine a circle, the circular area target can be identified by using only any three grid codes on the circular boundary.

[0091] In the prior art, the polygonal area in the polygon-to-grid method needs to be described by a large number of points, so a large number of longitude and latitude coordinates need to be input, that is, the amount of data required to be input by the polygon-to-grid method is large. The present invention only needs to input the center longitude and latitude of a circular area target to generate three grid codes that identify the circular area target.

[0092] In a specific embodiment, based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and the preset grid level, three first grid codes for identifying the circular area target are determined through a three-axis coordinate system. More specifically, the location of the central longitude and latitude of the circular area target is used as the origin of the three-axis coordinate system, a three-axis coordinate system is constructed on the circular area of ​​the circular area target, the target polygonal grids in the three coordinate axis directions of the three-axis coordinate system are determined, and the first grid codes for identifying the three target polygonal grids of the circular area target are generated.

[0093] Furthermore, based on the central longitude and latitude of the circular area target, the facets of the polyhedron where the circular area target is located are determined, so as to better determine the three first grid codes for identifying the circular area target. For example, based on the central longitude and latitude of the circular area target, according to the surface division rules, the specific facets in the spherical icosahedron corresponding to the central longitude and latitude are calculated; each facet represents an area of ​​the sphere, and this step limits the global positioning of the mission area to a smaller and more specific area.

[0094] Step 120, when the area target to be characterized is a polygonal area target, perform vertex extraction on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, and determine a second grid code at the plurality of target vertices based on the longitude and latitude of the plurality of target vertices and a preset grid level.

[0095] Here, the target area of ​​the polygonal area target is a polygonal area, that is, the boundary of the target area is a polygonal boundary.

[0096] Considering that the polygonal region of the polygonal region target has many vertices, in order to reduce the number of the second mesh codes, the polygonal region of the polygonal region target can be subjected to vertex extraction, that is, the polygonal region can be subjected to simplified boundary processing. That is, the second mesh code for identifying the polygonal region target can be simplified to better adapt to the limited hardware environment.

[0097] For ease of understanding, Figure 2 As shown, Figure 2 The polygon on the left is the polygon area of ​​the polygon area target, that is, the polygon area before simplifying the boundary. Figure 2 The polygon on the right is the target polygon area composed of multiple target vertices, that is, the polygon area after the simplified boundary. It should be understood that Figure 2 The polygons in can be polygonal areas that are not projected onto the sphere of the global discrete grid system, or polygonal areas that are projected onto the sphere of the global discrete grid system. Figure 2 It is just for the sake of ease of understanding. It does not mean that the processing must be done on a plane. It can also be done on a sphere.

[0098] The second mesh code at any of the target vertices is a code of a polygonal mesh covering the target vertex, and the mesh codes at the multiple target vertices are used to identify the polygonal area target.

[0099] In the prior art, the polygonal area in the polygon-to-grid method needs to be described by a large number of points, so a large number of longitude and latitude coordinates need to be input, that is, the polygon-to-grid method requires a large amount of input data. The present invention only needs to input the longitude and latitude of multiple extracted target vertices to generate a small number of second grid codes that identify the polygonal area target.

[0100] In one embodiment, based on the number of vertices of the polygonal area of ​​the polygonal area target and the preset storage requirement of the second mesh code, the number of second mesh codes to be extracted is determined, and based on the number of second mesh codes, vertices of the polygonal area of ​​the polygonal area target are extracted or deleted to obtain multiple target vertices after extraction.

[0101] In another embodiment, based on the shape of the polygonal area of ​​the polygonal area target and the preset representation accuracy requirement of the polygonal area target, vertex extraction or deletion is performed on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices.

[0102] In another embodiment, based on the number of vertices of the polygonal area of ​​the polygonal area target and the preset storage requirement of the second mesh code, the number of second mesh codes to be extracted is determined, and based on the shape of the polygonal area of ​​the polygonal area target, the preset characterization accuracy requirement of the polygonal area target and the number of second mesh codes, the polygonal area of ​​the polygonal area target is subjected to vertex extraction or deletion to obtain a plurality of extracted target vertices. In other words, based on the number and shape of the area target vertices, combined with the user's storage requirement for the mesh code and the accuracy requirement for the area target, the coordinates of the area target vertices are extracted or deleted while ensuring that the area range is consistent as much as possible (i.e., ensuring that the target polygonal area composed of multiple target vertices is as consistent as possible with the polygonal area coverage of the polygonal area target).

[0103] In a specific embodiment, based on the longitudes and latitudes of the multiple target vertices and a preset grid level, a longitude and latitude-to-grid coding method is used to determine the second grid codes at the multiple target vertices.

[0104] For ease of understanding, Figure 3 As shown, the polygonal mesh is a hexagonal mesh, the three-axis coordinate system is an IJK coordinate system, the mesh where the center position of the regional target (the target polygonal region composed of multiple target vertices) is located is the central mesh (the second central mesh), and multiple identification meshes (polygonal meshes corresponding to the second mesh code) cover each target vertex of the target polygonal region respectively. It should be understood that Figure 3 The area target in can be a polygonal area that is not projected onto the sphere of the global discrete grid system, or a polygonal area that is projected onto the sphere of the global discrete grid system. Figure 3 It is just for the sake of ease of understanding. It does not mean that the processing must be done on a plane. It can also be done on a sphere.

[0105] The regional target characterization method based on global discrete grids provided by an embodiment of the present invention, when the regional target to be characterized is a circular regional target, three first grid codes for identifying the circular regional target are determined based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and a preset grid level, and the central longitude and latitude are the longitude and latitude of the center position of the circular regional target, and any first grid code is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular regional target, so that only the first grid codes of the three target polygonal grids covering a partial circular boundary of the circular regional target are needed to characterize the circular regional target, and there is no need to characterize the circular regional target based on the grid codes of all grids covered by the polygonal area, that is, the three first grid codes can represent all grid codes within the circular area of ​​the circular regional target, thereby reducing the data storage amount and the transmission data amount of the device, thereby improving the grid coding efficiency of the device. transmission efficiency, and ultimately ensure that the regional target characterization method is executed on limited hardware devices; at the same time, in the case that the regional target to be characterized is a polygonal regional target, vertex extraction is performed on the polygonal area of ​​the polygonal regional target to obtain multiple target vertices after extraction, and second grid codes at multiple target vertices are determined based on the latitude and longitude of the multiple target vertices and the preset grid level, and the second grid code at any target vertex is the code of the polygonal grid covering the target vertex, and the grid codes at the multiple target vertices are used to identify the polygonal regional target, so that only the second grid code of some vertices of the polygonal area covering the polygonal regional target is needed to characterize the polygonal regional target, and there is no need to characterize the polygonal regional target based on the grid codes of all grids covered by the polygonal area, thereby reducing the data storage amount and transmission data amount of the device, improving the transmission efficiency of the grid code of the device, and ultimately ensuring that the regional target characterization method is executed on limited hardware devices.

[0106] Based on any of the above embodiments, in the method, in the above step 110, based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and the preset grid level, three first grid codes for identifying the circular area target are determined, including:

[0107] Based on the physical radius of the circular area target and the preset grid level, determine the number of first grids that the circular area target needs to cover within its radius area;

[0108] The grid where the central longitude and latitude of the circular area target are located is taken as the first central grid, and based on the first central grid and the first grid quantity, three first grid codes for identifying the circular area target are determined.

[0109] Since the grid level is used to characterize the size of a polygonal grid, and the size of each polygonal grid in the global discrete system is the same, based on this, based on the physical radius of the circular area target and the preset grid level, the first number of grids that the circular area target needs to cover within its radius area can be determined. The first number of grids is the number of polygonal grids, which can be understood as the radius of the polygonal area target expressed in the number of grid units, that is, the distance from the center position of the circular area target to the farthest grid that needs to be covered. The first number of grids is a distance measure for spherical grids.

[0110] In a specific embodiment, based on the physical radius of the circular area target, the target radius of the circular area target in the global discrete grid system is determined, and based on the target radius and the grid level, the first number of grids that the circular area target needs to cover within its radius area is determined.

[0111] Specifically, the grid where the central longitude and latitude of the circular area target are located is taken as the first central grid, and polygonal grids of the first number of grids are expanded outwards based on the first central grid to obtain a target polygonal grid covering a partial circular boundary of the circular area target.

[0112] The regional target characterization method based on global discrete grids provided in an embodiment of the present invention determines the number of first grids that the circular area target needs to cover within its radius area based on the physical radius of the circular area target and the preset grid level, takes the grid where the central longitude and latitude of the circular area target are located as the first central grid, and accurately determines three first grid codes for identifying the circular area target based on the first central grid and the number of first grids, thereby first determining the number of first grids that the circular area target needs to cover within its radius area, and taking the grid where the central longitude and latitude of the circular area target are located as the first central grid, so as to accurately determine the three target polygonal grids, and then accurately determine the three first grid codes, and finally improve the characterization accuracy of the circular area target.

[0113] Based on any of the above embodiments, in the method, determining the first number of grids that the circular area target needs to cover within its radius area based on the physical radius of the circular area target and the preset grid level includes:

[0114] Based on the physical radius of the circular area target, determining the target radius of the circular area target in the global discrete grid system;

[0115] The central longitude and latitude of the circular area target is used as the central position of the first central grid, and the number of first grids that the circular area target needs to cover within its radius area is determined based on the target radius and the grid level.

[0116] Considering that the physical radius is a radius in the real physical world, the physical radius is first converted into a target radius of a circular area target in a global discrete grid system, so as to facilitate the subsequent determination of the first grid number.

[0117] The regional target characterization method based on global discrete grids provided in an embodiment of the present invention determines the target radius of the circular area target in the global discrete grid system based on the physical radius of the circular area target, takes the position of the central longitude and latitude of the circular area target as the center position of the first center grid, and accurately determines the number of first grids that the circular area target needs to cover within its radius area based on the target radius and grid level, thereby first determining the target radius of the circular area target in the global discrete grid system, and taking the grid where the central longitude and latitude of the circular area target is located as the first center grid, and taking the position where the central longitude and latitude of the circular area target is located as the center position of the first center grid, so as to more accurately determine the three target polygonal grids, and then more accurately determine the three first grid codes, and finally further improve the characterization accuracy of the circular area target.

[0118] Based on any of the above embodiments, in the method, determining three first grid codes for identifying the circular area target based on the first central grid and the first number of grids includes:

[0119] Taking the central longitude and latitude of the circular area target as the origin of the three-axis coordinate system, and constructing the three-axis coordinate system on the circular area of ​​the circular area target;

[0120] Taking the first central grid as the center, determining a target polygonal grid in three coordinate axis directions of the three-axis coordinate system based on the first grid quantity;

[0121] A first mesh code for identifying the three target polygonal meshes of the circular area target is generated.

[0122] Here, the three-axis coordinate system may be an IJK coordinate system. Further, the angles of the three coordinate axes of the three-axis coordinate system are all 120 degrees, so that the three target polygonal meshes can be determined more accurately, and then the three first mesh codes can be determined more accurately.

[0123] Specifically, the grid where the central longitude and latitude of the circular area target are located is taken as the first central grid. With the first central grid as the center, polygonal grids of the first grid number are expanded outward along the three coordinate axes of the three-axis coordinate system to obtain a target polygonal grid covering part of the circular boundary of the circular area target.

[0124] In a specific embodiment, a unique first grid code is generated based on the position information of the target polygonal grid. The three first grid codes can be used as unique spatial identifiers of the circular area target in the global discrete grid system.

[0125] To facilitate understanding of the above embodiments, Figure 4 As shown, the polygonal grid is a hexagonal grid, the three-axis coordinate system is an IJK coordinate system, the location of the center longitude and latitude of the target area of ​​the circular area target is the origin of the three-axis coordinate system, the grid where the center longitude and latitude of the target area of ​​the circular area target is located is the center grid (first center grid), and the number of first grids that the target area of ​​the circular area target needs to cover within its radius area is 3. Based on this, the identification grids (target polygonal grids) in the three coordinate axis directions of the three-axis coordinate system are obtained, and the identification grids cover part of the circular boundary of the target area of ​​the circular area target. It should be understood that Figure 4 The target area in is a circular area that is not projected onto the sphere of the global discrete grid system, while Figure 4 The identification grid in is the grid on the sphere of the global discrete grid system. Figure 4 Just to make it easier to understand, it is not equivalent to processing on a plane, but processing on a sphere.

[0126] The method for characterizing regional targets based on global discrete grids provided by an embodiment of the present invention takes the central longitude and latitude of the circular regional target as the origin of the three-axis coordinate system, constructs a three-axis coordinate system on the circular area of ​​the circular regional target, takes the first central grid as the center, accurately determines the target polygonal grids in the three coordinate axis directions of the three-axis coordinate system based on the first grid quantity, accurately generates the first grid code for identifying the three target polygonal grids of the circular regional target, thereby using the three-axis coordinate system and taking the central longitude and latitude of the circular regional target as the origin of the three-axis coordinate system, taking the first central grid as the center, more accurately determines the three target polygonal grids based on the first grid quantity, and then more accurately determines the three first grid codes, and finally further improves the characterization accuracy of the circular regional target.

[0127] Based on any of the above embodiments, considering that in the prior art, when all grid codes in a polygonal area are converted back to geometric information of the polygonal area, the reverse calculation takes a long time due to the huge number of grid codes; based on this, Figure 5 This is the second flow chart of the regional target characterization method based on global discrete grid provided by the present invention, such as Figure 5 As shown, after the above step 110, the method further includes: step 510, step 520 and step 530.

[0128] Step 510, taking the central longitude and latitude of the circular area target as the rotation center point, the three target polygonal meshes are respectively rotated by 60 degrees to obtain three rotated polygonal meshes.

[0129] Considering that three target polygonal meshes and three rotated polygonal meshes are finally obtained, the three target polygonal meshes are rotated 60 degrees respectively based on this.

[0130] In other words, the grid where the central longitude and latitude of the circular area target are located is taken as the first central grid, and the position where the central longitude and latitude of the circular area target are located is taken as the center position of the first central grid, and the three target polygonal grids are rotated 60 degrees around the first central grid respectively to obtain three rotated polygonal grids.

[0131] It should be understood that rotating the three target polygonal meshes by 60 degrees respectively can expand the original coverage range so that the first characteristic hexagon can more completely cover the entire circular area.

[0132] Step 520 , respectively select one vertex from each of the three target polygonal meshes and the three rotated polygonal meshes to obtain six first vertices.

[0133] Specifically, a first vertex is selected in each polygon mesh. A target polygon mesh has a first vertex, and a rotation polygon mesh has a first vertex.

[0134] Step 530 , connecting the six first vertices in sequence to obtain a first characteristic hexagon covering the circular area of ​​the circular area target.

[0135] When the first characteristic hexagon is obtained, the grid code can be restored to the first characteristic hexagon close to the original area (polygonal area of ​​the circular area target), that is, it can be converted into geometric information that conforms to the real world. The first characteristic hexagon is a characteristic hexagon controlled by three first grid codes.

[0136] For ease of understanding, Figure 6As shown, the polygonal grid is a hexagonal grid, the three-axis coordinate system is an IJK coordinate system, the location of the center longitude and latitude of the target area of ​​the circular area target is the origin of the three-axis coordinate system, the grid where the center longitude and latitude of the target area of ​​the circular area target is located is the center grid (first center grid), the identification grid (target polygonal grid) in the three coordinate axis directions of the three-axis coordinate system, and the identification grid covers the partial circular boundary of the target area of ​​the circular area target, the location of the center longitude and latitude of the circular area target is the rotation center point, based on this, three rotation grids (rotation polygonal grids) are obtained, and finally the characteristic hexagon of the circular area covering the circular area target is obtained, and the rotation grid also covers the partial circular boundary of the target area of ​​the circular area target. It should be understood that Figure 6 The logo grid and rotation grid in are grids on the sphere of the global discrete grid system. Figure 6 The characteristic hexagons in are hexagons on the sphere of the global discrete grid system. Figure 6 Just to make it easier to understand, it is not equivalent to processing on a plane, but processing on a sphere.

[0137] It should be understood that the embodiment of the present invention is to restore the grid code into vector polygons to facilitate visualization or other vector analysis.

[0138] The regional target characterization method based on global discrete grids provided in an embodiment of the present invention takes the central longitude and latitude of the circular area target as the rotation center point, rotates the three target polygonal grids by 60 degrees respectively, and obtains three rotated polygonal grids, selects one vertex of each of the three target polygonal grids and the three rotated polygonal grids respectively, and obtains six first vertices, which are connected in sequence to obtain the first characteristic hexagon of the circular area covering the circular area target; through the above method, the first characteristic hexagon of the circular area covering the circular area target can be obtained based on only the three target polygonal grids, that is, the first characteristic hexagon of the circular area covering the circular area target can be restored based on only the three first grid codes, thereby reducing the time consumption of reverse calculation, that is, realizing bidirectional efficient calculation.

[0139] Based on any of the above embodiments, in the method, the above step 520 includes:

[0140] Based on the rotation center point, one vertex of each of the three target polygonal meshes and the three rotated polygonal meshes is selected to obtain six first vertices.

[0141] Among them, the distance between the first vertex of any polygonal mesh and the rotation center point is greater than the distance between other vertices of the polygonal mesh except the first vertex and the rotation center point, so that the first characteristic hexagon completely covers the circular area of ​​the circular area target.

[0142] Exemplarily, assuming that the polygonal mesh is a hexagonal mesh, the distance between the first vertex of the six vertices of the hexagonal mesh and the rotation center point is greater than the distance between the other five vertices of the six vertices and the rotation center point, so that the first feature polygon covers the original area as much as possible.

[0143] The regional target characterization method based on global discrete grids provided in an embodiment of the present invention selects one vertex of each of the three target polygonal meshes and the three rotated polygonal meshes based on the rotation center point to obtain six first vertices, so that the first characteristic hexagon completely covers the circular area of ​​the circular area target, thereby avoiding loss of information. For example, the first characteristic hexagon completely covers the task area, ensuring that no important information is missed during data collection.

[0144] Based on any of the above embodiments, Figure 7 This is the third flow chart of the regional target characterization method based on global discrete grid provided by the present invention, such as Figure 7 As shown, after the above step 530, the method further includes: step 710, step 720 and step 730.

[0145] Step 710, taking the grid where the central longitude and latitude of the circular area target are located as the first central grid, and taking the position where the central longitude and latitude of the circular area target are located as the center position of the first central grid, and determining the number of second grids required to cover the area from any vertex of the first characteristic hexagon to the center position of the first central grid.

[0146] The second number of meshes is N. The second number of meshes is the number of polygonal meshes.

[0147] In other words, the number of second grids required to be covered in the region from any vertex of the first characteristic hexagon to the first central grid is determined.

[0148] Step 720: Based on the second number of grids, grids are expanded outward on the basis of the first central grid to obtain a plurality of first extended grids.

[0149] The second number of grids is used to indicate that the expansion stops after N-1 first expansion grids are expanded outward in one direction.

[0150] In other words, based on the first central grid, adjacent grids (first extended grids) of the second grid order are generated, that is, adjacent grids around the first central grid are accurately retrieved and located based on the second grid order.

[0151] Step 730: taking the union of the first central grid and the plurality of first extended grids as the grid set of the first characteristic hexagon.

[0152] In other words, the grid set of the first characteristic hexagon includes a first central grid and a plurality of first extended grids, that is, a grid unit set within the first characteristic hexagon is determined.

[0153] After obtaining the grid set of the first characteristic hexagon, it can provide the necessary basic data for the subsequent observation task data processing, analysis and visualization, which is convenient for target disassembly and spatial calculation.

[0154] For ease of understanding, Figure 8 As shown, the polygonal grid is a hexagonal grid, the grid where the central longitude and latitude of the circular area target is located is the first central grid, the position where the central longitude and latitude of the circular area target is located is the center position of the first central grid, and the number of second grids is 3. Based on this, the following is obtained: Figure 8 The grid unit set of all hexagonal grids in (the grid unit set of the first characteristic hexagon). It should be understood that Figure 8 The polygonal mesh in is a mesh on a sphere of the global discrete grid system. Figure 8 The characteristic hexagons in are hexagons on the sphere of the global discrete grid system. Figure 8 Just to make it easier to understand, it is not equivalent to processing on a plane, but processing on a sphere.

[0155] The regional target characterization method based on global discrete grids provided by an embodiment of the present invention takes the grid where the central longitude and latitude of the circular regional target is located as the first central grid, and takes the position where the central longitude and latitude of the circular regional target is located as the center position of the first central grid, accurately determines the number of second grids required to cover the area from any vertex of the first characteristic hexagon to the center position of the first central grid, and based on the second number of grids, expands the grid outward on the basis of the first central grid to accurately obtain multiple first extended grids, and the number of second grids is N, and the second number of grids is used to indicate that the expansion stops after N-1 first extended grids are expanded outward in one direction, and finally the union of the first central grid and the multiple first extended grids is taken as the grid set of the first characteristic hexagon, thereby improving the determination accuracy of the grid set of the first characteristic hexagon.

[0156] Based on the above embodiments, the present invention realizes a circular area target characterization method based on grid coding, which has simple input, concise output, small data volume, and can perform bidirectional efficient calculations. Compared with the traditional method that requires inputting several vertex coordinates of the polygonal area in the polygon-to-grid algorithm, the present method only needs to input a longitude and latitude coordinate, radius, and grid level to realize the circular area to grid conversion. After the circular area is converted to a grid, only three grid codes need to be output. These three grid codes can represent all grid codes within the circular area, creating favorable conditions for data storage and transmission. In addition, it is possible to realize the conversion of the circular area to a grid code, and also to restore the grid code to a characteristic hexagon close to the original area.

[0157] Based on any of the above embodiments, in the method, in the above step 120, the polygonal area of ​​the polygonal area target is subjected to vertex extraction to obtain a plurality of extracted target vertices, including:

[0158] Based on the grid level, vertex extraction is performed on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, so that a polygonal mesh represented by the grid level only covers one vertex at any boundary position of the polygonal area.

[0159] In a specific embodiment, a polygonal mesh represented by a mesh level is slid on the boundary of a polygonal area of ​​a polygonal area target. If a polygonal mesh represented by a mesh level covers multiple vertices of the polygonal area during the sliding process, then one target vertex is extracted from the multiple vertices, thereby ensuring that the polygonal mesh only covers one vertex of a polygonal area at the same position.

[0160] The regional target characterization method based on global discrete grid provided by the embodiment of the present invention extracts vertices of the polygonal area of ​​the polygonal area target based on the grid level to obtain multiple target vertices after extraction, so that a polygonal mesh represented by the grid level only covers one vertex at any boundary position of the polygonal area, so that only the second grid code covering part of the vertices of the polygonal area of ​​the polygonal area target is needed to characterize the polygonal area target, thereby reducing the data storage amount and transmission data amount of the device, thereby improving the transmission efficiency of the grid code of the device, and finally ensuring that the regional target characterization method is executed on limited hardware devices; and the above method can accurately extract vertices to ensure that the target polygonal area composed of multiple target vertices is as consistent as possible with the polygonal area coverage of the polygonal area target, thereby improving the characterization accuracy of the polygonal area target.

[0161] Based on any of the above embodiments, Fig. 9 This is a fourth flow chart of the regional target characterization method based on global discrete grid provided by the present invention, such as Fig. 9As shown, after the above step 120, the method further includes: step 910, step 920 and step 930.

[0162] Step 910: Based on the multiple target vertices, determine the center position of the target polygonal area formed by the multiple target vertices.

[0163] It should be noted that based on the coordinates of multiple target vertices of the target polygonal area, the coordinates of the center position of the target polygonal area can be calculated. The calculation method can be selected from the existing technical method as needed, and will not be described here.

[0164] Step 920 , based on the center position of the target polygonal area, select a vertex of the polygonal meshes corresponding to the plurality of second mesh codes respectively to obtain a plurality of second vertices.

[0165] Among them, the distance between the second vertex of the polygon mesh corresponding to any second mesh code and the center position of the target polygonal area is greater than the distance between other vertices of the polygon mesh corresponding to the second mesh code except the second vertex and the center position of the target polygonal area.

[0166] Specifically, a second vertex is selected in each polygon mesh.

[0167] Exemplarily, assuming that the polygonal mesh is a hexagonal mesh, the distance between the second vertex of the six vertices of the hexagonal mesh and the center position of the target polygonal area is greater than the distance between the other five vertices of the six vertices and the center position of the target polygonal area, so that the second feature polygon covers the original area as much as possible.

[0168] Step 930: connect the plurality of second vertices in sequence to obtain a second characteristic hexagon that completely covers the target polygonal area.

[0169] When the second characteristic hexagon is obtained, the grid encoding can be restored to the second characteristic hexagon close to the original area (the polygonal area of ​​the polygonal area target), that is, it can be converted into geometric information that conforms to the real world.

[0170] Exemplarily, the grid code of the target center point of the area is determined based on the longitude and latitude of the center position of the target polygonal area, and the second grid codes corresponding to multiple second vertices are traversed. In combination with the position and orientation of the grid relative to the second center grid in the three-axis coordinate system, the vertex among the grid vertices that is farthest from the second center grid is taken as the vertex of the second characteristic polygon.

[0171] In other words, according to the maximum coverage area principle, a second characteristic hexagon that completely covers the target polygonal area is determined.

[0172] For ease of understanding, Fig.10 As shown, the polygonal mesh is a hexagonal mesh, the three-axis coordinate system is an IJK coordinate system, the mesh where the center position of the regional target (the target polygonal region composed of multiple target vertices) is located is the central mesh (the second central mesh), and multiple identification meshes (polygonal meshes corresponding to the second mesh code) respectively cover the target vertices of the target polygonal region. Based on this, a characteristic hexagon (the second characteristic hexagon) that completely covers the target polygonal region is obtained. It should be understood that Fig.10 The identification grid and the center grid in are the grids on the sphere of the global discrete grid system. Fig.10 The characteristic hexagons in are hexagons on the sphere of the global discrete grid system. Fig.10 Just to make it easier to understand, it is not equivalent to processing on a plane, but processing on a sphere.

[0173] It should be understood that the embodiment of the present invention is to restore the grid code into vector polygons to facilitate visualization or other vector analysis.

[0174] The regional target characterization method based on global discrete grid provided by the embodiment of the present invention determines the center position of the target polygonal area composed of multiple target vertices based on multiple target vertices, and selects one vertex of the polygonal grid corresponding to multiple second grid codes based on the center position of the target polygonal area to obtain multiple second vertices, and the distance between the second vertex of the polygonal grid corresponding to any second grid code and the center position of the target polygonal area is greater than the distance between the other vertices of the polygonal grid corresponding to the second grid code except the second vertex and the center position of the target polygonal area, so that the second characteristic hexagon completely covers the target polygonal area composed of multiple target vertices, thereby avoiding information loss, for example, making the second characteristic hexagon completely cover the task area, ensuring that no important information is missed during data collection; through the above method, the second characteristic hexagon covering the target polygonal area can be restored based on only a small number of second grid codes, thereby reducing the time consumption of reverse calculation, that is, achieving bidirectional efficient calculation.

[0175] Based on any of the above embodiments, Fig.11 This is a fifth flow chart of the regional target characterization method based on global discrete grid provided by the present invention, such as Fig.11 As shown, after the above step 930, the method further includes: step 1110, step 1120 and step 1130.

[0176] Step 1110: Use the grid where the center position of the target polygonal area is located as the second center grid.

[0177] Step 1120: Based on the second characteristic hexagon and the preset expansion requirement, the grid is expanded outward on the basis of the second central grid to obtain a plurality of second expanded grids.

[0178] The preset expansion requirement is used to indicate that the second extended grid obtained by expanding outward in one direction stops expanding when it reaches the boundary of the second characteristic hexagon, and the preset expansion requirement is used to make the second central grid and the multiple second extended grids completely cover the second characteristic hexagon together.

[0179] In other words, based on the second central grid, neighboring grids around the second central grid are retrieved and located.

[0180] Step 1130: taking the union of the second central grid and the plurality of second extended grids as the grid set of the second characteristic hexagon.

[0181] In other words, the grid set of the second characteristic hexagon includes a second central grid and a plurality of second extended grids, that is, a grid unit set within the second characteristic hexagon is determined.

[0182] After obtaining the grid set of the second characteristic hexagon, it can provide the necessary basic data for the subsequent observation task data processing, analysis and visualization, which is convenient for target disassembly and spatial calculation.

[0183] Correspondingly, a grid code set of the second characteristic hexagon can be obtained by the above method, and the grid code set includes the grid codes of each polygonal grid in the grid set.

[0184] In one embodiment, the grid codes between every two adjacent target vertices are obtained in turn in the three-axis coordinate system to obtain the boundary line grid codes; based on the second central grid, the neighboring grid codes are queried outward according to the neighboring grid search algorithm, and the neighboring query in this direction is stopped when the neighboring grid code coincides with the boundary line grid code; when all neighboring grids reach the boundary line grid corresponding to the boundary line grid code, the neighboring search ends, and the grid code set of the second characteristic hexagon is obtained.

[0185] The boundary line grid code includes all grid codes between two adjacent target vertices, that is, after knowing the second grid codes of the two target vertices, it is easy to determine the orientation in the three-axis coordinate system and calculate all grid codes between them. The grid code in the area can be quickly obtained using the neighbor search algorithm.

[0186] It should be understood that when the user wants to obtain all grid codes in the area, they can be quickly calculated using a small amount of second grid codes in the above manner.

[0187] For ease of understanding, Fig.12As shown, the polygonal mesh is a hexagonal mesh, the three-axis coordinate system is the IJK coordinate system, the mesh where the center position of the regional target (the target polygonal region composed of multiple target vertices) is located is the central mesh (the second central mesh), and multiple identification meshes (polygonal meshes corresponding to the second mesh code) respectively cover the target vertices of the target polygonal region. Based on this, the second characteristic hexagonal mesh set is obtained, which includes Fig.12 All polygon meshes in . It should be understood that Fig.12 The identification grid and the center grid in are the grids on the sphere of the global discrete grid system. Fig.12 The regional targets in are polygons on a sphere of a global discrete grid system. Fig.12 Just to make it easier to understand, it is not equivalent to processing on a plane, but processing on a sphere.

[0188] The regional target characterization method based on global discrete grids provided by the embodiment of the present invention takes the grid where the center position of the target polygonal area is located as the second central grid; based on the second characteristic hexagon and the preset expansion requirement, the grid is expanded outward on the basis of the second central grid to obtain multiple second extended grids, and the preset expansion requirement is used to indicate that the second extended grid obtained by expanding outward in one direction stops expanding when it reaches the boundary of the second characteristic hexagon, and the preset expansion requirement is used to make the second central grid and the multiple second extended grids completely cover the second characteristic hexagon together to ensure that no information is missed, and the union of the second central grid and the multiple second extended grids is used as the grid set of the second characteristic hexagon, thereby improving the accuracy of determining the grid set of the second characteristic hexagon. Based on the above embodiments, the present invention realizes a polygonal regional target characterization method based on grid coding with small storage, transmission and calculation amount, and bidirectional efficient conversion. Compared with the traditional "global grid coding" regional target characterization method that requires a large number of grid codes to identify regional targets, the present invention only needs a small number of grid codes to realize polygonal regional target identification. And bidirectional efficient conversion can be performed. When it is necessary to obtain the boundary data of regional targets, the grid codes that identify the regional targets can be quickly converted into regional feature polygons, which is conducive to visualization and other vector analysis. In addition, all grid codes in the region can be quickly obtained. When the user needs all grid codes in the region, a small number of codes that identify regional targets can also be converted into all grid codes in the region through the neighboring search algorithm.

[0189] In addition, the above embodiments are applicable to any hexagonal discrete grid (such as three-aperture, four-aperture and seven-aperture).

[0190] The regional target characterization device based on global discrete grid provided by the present invention is described below. The regional target characterization device based on global discrete grid described below and the regional target characterization method based on global discrete grid described above can be referred to each other.

[0191] Fig.13 is a schematic diagram of the structure of a regional target characterization device based on a global discrete grid provided by the present invention, such as Fig.13 As shown, the regional target characterization device based on the global discrete grid includes a first determination module 1310 and a second determination module 1320 .

[0192] The first determination module 1310 is used to determine three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level when the area target to be characterized is a circular area target; the central longitude and latitude are the longitude and latitude of the center position of the circular area target, any of the first grid codes is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular area target.

[0193] The second determination module 1320 is used to extract vertices from the polygonal area of ​​the polygonal area target when the area target to be represented is a polygonal area target, to obtain multiple target vertices after extraction, and to determine the second grid codes at the multiple target vertices based on the longitude and latitude of the multiple target vertices and a preset grid level; the second grid code at any of the target vertices is the code of the polygonal grid covering the target vertex, and the grid codes at the multiple target vertices are used to identify the polygonal area target.

[0194] The mesh level is used to represent the size of a polygonal mesh.

[0195] The regional target characterization device based on global discrete grids provided by the embodiment of the present invention, when the regional target to be characterized is a circular regional target, determines three first grid codes for identifying the circular regional target based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and the preset grid level, and the central longitude and latitude are the longitude and latitude of the central position of the circular regional target, and any first grid code is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular regional target, so that only the first grid codes of the three target polygonal grids covering a partial circular boundary of the circular regional target are needed to characterize the circular regional target, and there is no need to characterize the circular regional target based on the grid codes of all grids covered by the polygonal area, that is, the three first grid codes can represent all grid codes within the circular area of ​​the circular regional target, thereby reducing the data storage amount and the transmission data amount of the device, thereby improving the grid coding efficiency of the device. transmission efficiency, and ultimately ensure that the regional target characterization method is executed on limited hardware devices; at the same time, in the case that the regional target to be characterized is a polygonal regional target, vertex extraction is performed on the polygonal area of ​​the polygonal regional target to obtain multiple target vertices after extraction, and second grid codes at multiple target vertices are determined based on the latitude and longitude of the multiple target vertices and the preset grid level, and the second grid code at any target vertex is the code of the polygonal grid covering the target vertex, and the grid codes at the multiple target vertices are used to identify the polygonal regional target, so that only the second grid code of some vertices of the polygonal area covering the polygonal regional target is needed to characterize the polygonal regional target, and there is no need to characterize the polygonal regional target based on the grid codes of all grids covered by the polygonal area, thereby reducing the data storage amount and transmission data amount of the device, improving the transmission efficiency of the grid code of the device, and ultimately ensuring that the regional target characterization method is executed on limited hardware devices.

[0196] Fig.14 An example of a physical structure diagram of an electronic device is shown in FIG. Fig.14As shown, the electronic device may include: a processor (processor) 1410 , a communication interface (Communications Interface) 1420 , a memory (memory) 1430 and a communication bus 1440 , wherein the processor 1410 , the communication interface 1420 , and the memory 1430 communicate with each other through the communication bus 1440 . The processor 1410 can call the logic instructions in the memory 1430 to execute the regional target characterization method based on the global discrete grid, which includes: when the regional target to be characterized is a circular regional target, based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and a preset grid level, three first grid codes for identifying the circular regional target are determined; the central longitude and latitude are the longitude and latitude of the center position of the circular regional target, any of the first grid codes is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular regional target; when the regional target to be characterized is a polygonal regional target, vertices of the polygonal region of the polygonal regional target are extracted to obtain multiple extracted target vertices, and based on the longitude and latitude of the multiple target vertices and the preset grid level, second grid codes at the multiple target vertices are determined; the second grid code at any of the target vertices is the code of the polygonal grid covering the target vertex, and the grid codes at the multiple target vertices are used to identify the polygonal regional target; wherein the grid level is used to characterize the size of a polygonal grid.

[0197] In addition, the logic instructions in the above-mentioned memory 1430 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a disk or an optical disk.

[0198] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the regional target characterization method based on the global discrete grid provided by the above methods, the method comprising: when the regional target to be characterized is a circular regional target, based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and a preset grid level, determining three first grid codes for identifying the circular regional target; the central longitude and latitude are the longitude and latitude of the center position of the circular regional target, and any of the first grid codes is The grid code is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular area target; when the area target to be characterized is a polygonal area target, vertex extraction is performed on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, and based on the longitude and latitude of the plurality of target vertices and a preset grid level, a second grid code at the plurality of target vertices is determined; the second grid code at any of the target vertices is the code of the polygonal grid covering the target vertex, and the grid codes at the plurality of target vertices are used to identify the polygonal area target; wherein the grid level is used to characterize the size of a polygonal grid.

[0199] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when executed by a processor to execute the regional target characterization method based on the global discrete grid provided by the above-mentioned methods, the method comprising: in the case where the regional target to be characterized is a circular regional target, based on the central longitude and latitude of the circular regional target, the physical radius of the circular regional target and a preset grid level, three first grid codes for identifying the circular regional target are determined; the central longitude and latitude are the longitude and latitude of the central position of the circular regional target, any of the first grid codes is the code of the target polygonal grid, and the target polygonal grid is a grid covering a partial circular boundary of the circular regional target; in the case where the regional target to be characterized is a polygonal regional target, vertex extraction is performed on the polygonal area of ​​the polygonal regional target to obtain a plurality of extracted target vertices, and based on the longitude and latitude of the plurality of target vertices and the preset grid level, a second grid code at the plurality of target vertices is determined; the second grid code at any of the target vertices is the code of the polygonal grid covering the target vertex, and the grid code at the plurality of target vertices is used to identify the polygonal regional target; wherein the grid level is used to characterize the size of a polygonal grid.

[0200] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0201] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0202] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A regional target characterization method based on global discrete grid, characterized in that: include: In the case where the area target to be characterized is a circular area target, based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level, three first grid codes for identifying the circular area target are determined; The center longitude and latitude are the longitude and latitude of the center position of the circular area target, any of the first grid codes is the code of the target polygonal grid, and the target polygonal grid is a grid covering a part of the circular boundary of the circular area target; When the area target to be characterized is a polygonal area target, extracting vertices of the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, and determining second grid codes at the plurality of target vertices based on the longitudes and latitudes of the plurality of target vertices and a preset grid level; The second mesh code at any of the target vertices is a code of a polygonal mesh covering the target vertex, and the mesh codes at the multiple target vertices are used to identify the polygonal area target; Wherein, the mesh level is used to represent the size of a polygonal mesh; The determining of three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level includes: Based on the physical radius of the circular area target and the preset grid level, determine the number of first grids that the circular area target needs to cover within its radius area; Taking the grid where the central longitude and latitude of the circular area target are located as the first central grid, and determining three first grid codes for identifying the circular area target based on the first central grid and the first grid quantity; The determining, based on the first central grid and the first grid quantity, three first grid codes for identifying the circular area target comprises: Taking the central longitude and latitude of the circular area target as the origin of the three-axis coordinate system, and constructing the three-axis coordinate system on the circular area of ​​the circular area target; Taking the first central grid as the center, determining a target polygonal grid in three coordinate axis directions of the three-axis coordinate system based on the first grid quantity; Generating a first mesh code for identifying three target polygonal meshes of the circular area target; The step of extracting vertices from the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices includes: Based on the grid level, vertex extraction is performed on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, so that a polygonal mesh represented by the grid level only covers one vertex at any boundary position of the polygonal area.

2. The method for characterizing regional targets based on global discrete grids according to claim 1, characterized in that: The determining, based on the physical radius of the circular area target and the preset grid level, the first number of grids that the circular area target needs to cover within the radius area range includes: Based on the physical radius of the circular area target, determining the target radius of the circular area target in the global discrete grid system; The central longitude and latitude of the circular area target is used as the central position of the first central grid, and the number of first grids that the circular area target needs to cover within its radius area is determined based on the target radius and the grid level.

3. The method for characterizing regional targets based on global discrete grids according to any one of claims 1 to 2, characterized in that: After determining three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and the preset grid level, the method further includes: Taking the central longitude and latitude of the circular area target as the rotation center point, the three target polygonal meshes are respectively rotated by 60 degrees to obtain three rotated polygonal meshes; Selecting one vertex from each of the three target polygonal meshes and the three rotated polygonal meshes respectively to obtain six first vertices; The six first vertices are connected in sequence to obtain a first characteristic hexagon covering the circular area of ​​the circular area target.

4. The method for characterizing regional targets based on global discrete grids according to claim 3, characterized in that: The step of respectively selecting one vertex from each of the three target polygonal meshes and the three rotated polygonal meshes to obtain six first vertices includes: Based on the rotation center point, select one vertex of each of the three target polygonal meshes and the three rotated polygonal meshes to obtain six first vertices; Among them, the distance between the first vertex of any polygonal mesh and the rotation center point is greater than the distance between other vertices of the polygonal mesh except the first vertex and the rotation center point, so that the first characteristic hexagon completely covers the circular area of ​​the circular area target.

5. The method for characterizing regional targets based on global discrete grids according to claim 3, characterized in that: After sequentially connecting the six first vertices to obtain a first characteristic hexagon covering the circular area of ​​the circular area target, the method further includes: The grid where the central longitude and latitude of the circular area target is located is taken as the first central grid, and the position where the central longitude and latitude of the circular area target is located is taken as the center position of the first central grid, and the number of second grids required to be covered in the area from any vertex of the first characteristic hexagon to the center position of the first central grid is determined; the number of the second grids is N; Based on the second number of grids, grids are expanded outward on the basis of the first central grid to obtain multiple first extended grids; the second number of grids is used to indicate that the expansion stops after N-1 first extended grids are expanded outward in one direction; A union of the first central grid and the plurality of first extended grids is used as a grid set of the first characteristic hexagon.

6. The method for characterizing regional targets based on global discrete grids according to claim 1, characterized in that: After determining the second grid codes at the multiple target vertices based on the longitudes and latitudes of the multiple target vertices and the preset grid level, the method further includes: Based on the multiple target vertices, determining a center position of a target polygonal area formed by the multiple target vertices; Based on the center position of the target polygonal area, a vertex of the polygonal meshes corresponding to the plurality of second mesh codes is respectively selected to obtain a plurality of second vertices; the distance between the second vertex of the polygonal mesh corresponding to any of the second mesh codes and the center position of the target polygonal area is greater than the distance between the other vertices of the polygonal mesh corresponding to the second mesh code except the second vertex and the center position of the target polygonal area; The plurality of second vertices are connected in sequence to obtain a second characteristic hexagon that completely covers the target polygonal area.

7. The method for characterizing regional targets based on global discrete grids according to claim 6, characterized in that: After sequentially connecting the plurality of second vertices to obtain a second characteristic hexagon that completely covers the target polygonal area, the method further includes: The grid where the center position of the target polygonal area is located is used as the second center grid; Based on the second characteristic hexagon and the preset expansion requirement, a grid is expanded outwardly on the basis of the second central grid to obtain a plurality of second extended grids; the preset expansion requirement is used to indicate that the second extended grid obtained by expanding outwardly in one direction stops expanding when it reaches the boundary of the second characteristic hexagon, and the preset expansion requirement is used to make the second central grid and the plurality of second extended grids completely cover the second characteristic hexagon together; A union of the second central grid and the plurality of second extended grids is used as a grid set of the second characteristic hexagon.

8. A regional target characterization device based on global discrete grid, characterized in that: include: A first determination module is used to determine three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level when the area target to be characterized is a circular area target; The center longitude and latitude are the longitude and latitude of the center position of the circular area target, any of the first grid codes is the code of the target polygonal grid, and the target polygonal grid is a grid covering a part of the circular boundary of the circular area target; A second determination module is used for, when the area target to be characterized is a polygonal area target, extracting vertices from the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, and determining second grid codes at the plurality of target vertices based on the longitudes and latitudes of the plurality of target vertices and a preset grid level; The second mesh code at any of the target vertices is a code of a polygonal mesh covering the target vertex, and the mesh codes at the multiple target vertices are used to identify the polygonal area target; Wherein, the mesh level is used to represent the size of a polygonal mesh; The determining of three first grid codes for identifying the circular area target based on the central longitude and latitude of the circular area target, the physical radius of the circular area target and a preset grid level includes: Based on the physical radius of the circular area target and the preset grid level, determine the number of first grids that the circular area target needs to cover within its radius area; Taking the grid where the central longitude and latitude of the circular area target are located as the first central grid, and determining three first grid codes for identifying the circular area target based on the first central grid and the first grid quantity; The determining, based on the first central grid and the first grid quantity, three first grid codes for identifying the circular area target comprises: Taking the central longitude and latitude of the circular area target as the origin of the three-axis coordinate system, and constructing the three-axis coordinate system on the circular area of ​​the circular area target; Taking the first central grid as the center, determining a target polygonal grid in three coordinate axis directions of the three-axis coordinate system based on the first grid quantity; Generating a first mesh code for identifying three target polygonal meshes of the circular area target; The step of extracting vertices from the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices includes: Based on the grid level, vertex extraction is performed on the polygonal area of ​​the polygonal area target to obtain a plurality of extracted target vertices, so that a polygonal mesh represented by the grid level only covers one vertex at any boundary position of the polygonal area.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the method for regional target characterization based on a global discrete grid as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for regional target characterization based on a global discrete grid as claimed in any one of claims 1 to 7 is implemented.

11. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the method for regional target characterization based on a global discrete grid as claimed in any one of claims 1 to 7 is implemented.

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