Batch extraction method, device and product of landslide parameters based on DEM

Abstract

The present application provides a method, device and product for batch extraction of landslide parameters based on DEM, which relates to the field of landslide measurement technology. The present application converts the boundary data of batch landslides into a unified projection coordinate system and combines it with elevation data to obtain the target rectangle of each landslide, and then calculates the landslide parameters of each landslide through the target rectangle. The present application greatly improves the efficiency of landslide parameter extraction, reduces the workload of manual measurement, and is suitable for batch processing of landslide parameters in large-scale landslide databases. Through automated calculation and batch processing, key parameters can be quickly and accurately obtained, and the accuracy and efficiency of landslide analysis can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of landslide measurement, and in particular to a method, device and product for batch extraction of landslide parameters based on DEM. Background Art

[0002] At present, the methods for obtaining landslide shape parameters such as length, width, slope direction, and slope are all measurement and estimation methods for single landslides. For example, laser rangefinders and remote sensing measurement methods are used to measure the length and width of the landslide, and compasses and other methods are used to measure the slope direction and slope.

[0003] The above methods usually involve very tedious manual annotation and calculation in the data of geographic maps, or manually importing the above parameters measured by individual landslides into the landslide database one by one. In addition, for landslide databases interpreted through remote sensing images for earthquakes, rainfall, etc., there are many landslides in the database. Since the shape parameters such as the length, width, slope direction, and slope of the landslide cannot be directly measured in the field, the acquisition of the above landslide parameters usually requires a lot of manpower and material resources to measure and confirm them one by one through remote sensing images. Moreover, since the slope direction, slope, length, width, etc. of individual landslides cannot be obtained, the existing regional landslide analysis uses various statistical values ​​of the slope and direction of the grid within the landslide range to represent the slope direction of the landslide, resulting in inaccurate analysis results.

[0004] Therefore, a new method for batch extraction of landslide parameters is urgently needed. Summary of the invention

[0005] In view of the above problems, the embodiments of the present application provide a method, device and product for batch extraction of landslide parameters based on DEM, so as to overcome the above problems or at least partially overcome the above problems.

[0006] In a first aspect, the present application provides a method for batch extraction of landslide parameters based on DEM, the method comprising:

[0007] Obtain boundary data of multiple landslides in the target area, and elevation data corresponding to the boundary data of each landslide;

[0008] The boundary data of each landslide is converted into a projection coordinate system through projection transformation, and the three-dimensional coordinates corresponding to the boundary data of each landslide are obtained in combination with the elevation data corresponding to the boundary data of each landslide;

[0009] According to the three-dimensional coordinates corresponding to the boundary data of each landslide, respectively determining the target rectangle corresponding to each landslide in the projection coordinate system;

[0010] According to the target rectangle corresponding to each landslide, determine the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide;

[0011] Calculating the three-dimensional coordinates of the midpoints of the sides of each target rectangle according to the three-dimensional coordinates of the corner points of the target rectangle corresponding to each landslide;

[0012] The landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle.

[0013] Optionally, the landslide parameter includes: landslide length, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0014] The multiple landslides in the target area are numbered, each landslide is traversed in the order of the numbers, and the landslide length of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows:

[0015] Determine the Z-axis coordinate value of the midpoint of each side of the target rectangle of the target landslide from the three-dimensional coordinates of the midpoint of each side of the target rectangle of the target landslide;

[0016] Determine the maximum Z-axis coordinate value and the minimum Z-axis coordinate value of the target landslide according to the Z-axis coordinate values ​​of the midpoints of the respective sides of the target rectangle of the target landslide;

[0017] The maximum Z-axis coordinate value of the midpoints of the target rectangle of the target landslide is determined as the highest point of the target landslide, and the minimum Z-axis coordinate value is determined as the lowest point of the target landslide;

[0018] The landslide length of the target landslide is calculated according to the projection coordinates of the highest point and the projection coordinates of the lowest point.

[0019] Optionally, the landslide parameter includes: landslide width, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0020] Each landslide is traversed in the order of the numbers, and the landslide width of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows:

[0021] Obtaining the projection coordinates of two other midpoints of the midpoints of the target rectangle of the target landslide, except for the midpoint corresponding to the maximum Z-axis coordinate value and the midpoint corresponding to the minimum Z-axis coordinate value;

[0022] The landslide width of the target landslide is calculated according to the projection coordinates of the other two midpoints.

[0023] Optionally, the landslide parameters include: landslide direction, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0024] Traverse each landslide in the order of the numbers, and calculate the landslide direction of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0025] Determine a target angle between a line connecting the highest point and the lowest point and a preset direction according to the projection coordinates of the highest point and the projection coordinates of the lowest point of the target rectangle of the target landslide;

[0026] Calculate the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and calculate the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point;

[0027] The landslide direction of the target landslide is determined according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle.

[0028] Optionally, determining the slope direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle includes:

[0029] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than or equal to zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than or equal to zero, then the slope direction of the target landslide is determined to be the sum of the first target angle and the target angle; or,

[0030] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero, then the slope direction of the target landslide is determined to be the difference between the second target angle and the target angle; or,

[0031] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero, then the slope direction of the target landslide is determined to be the target angle; or,

[0032] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than zero, then the slope direction of the target landslide is determined to be the difference between the first target angle and the target angle.

[0033] Optionally, the landslide parameter includes: landslide slope, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0034] Traverse each landslide in the order of the numbers, and calculate the landslide slope of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0035] According to the three-dimensional coordinates of the highest point and the three-dimensional coordinates of the lowest point of the target rectangle of the target landslide, respectively calculate the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point;

[0036] The landslide slope of the target landslide is calculated based on the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point.

[0037] Optionally, determining the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide respectively includes:

[0038] According to the three-dimensional coordinates of the boundary data of any of the landslides, a plurality of boundary circumscribed rectangles of the landslide are obtained by spatial calculation in the projection coordinate system;

[0039] By comparing the plurality of bounding rectangles in pairs, determining a bounding rectangle with the smallest width among the plurality of bounding rectangles;

[0040] The bounding rectangle of the minimum width is determined as the target rectangle.

[0041] Optionally, the landslide parameters include: landslide representative points, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0042] Traverse each landslide in the order of the numbers, and calculate the representative points of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0043] The representative point of the target landslide is calculated based on the projection coordinates of the highest point and the projection coordinates of the lowest point, wherein the representative point of the target landslide is located at half of the line connecting the highest point and the lowest point, or the representative point of the target landslide is located at two-thirds of the line connecting the lowest point to the highest point.

[0044] Optionally, the step of converting the boundary data of each landslide into a projection coordinate system through projection transformation comprises:

[0045] Obtaining the original coordinate system corresponding to the boundary data of each landslide and the geographical location of the target area;

[0046] Determine a projection coordinate system corresponding to the target area according to the geographical location of the target area;

[0047] According to the projection coordinate system and the original coordinate system corresponding to the boundary data of each landslide, the boundary data of each landslide is converted from the original coordinate system to the projection coordinate system through coordinate system conversion.

[0048] Optionally, before converting the boundary data of each landslide from the original coordinate system to the projected coordinate system, the method further comprises:

[0049] The coordinate consistency correction is performed on the boundary data of each landslide.

[0050] Optionally, after acquiring boundary data of a plurality of landslides in the target area, the method further comprises:

[0051] Preprocess the boundary data of each landslide separately;

[0052] The pre-processing measures include: filtering the boundary data of each landslide, or using a difference algorithm to supplement the missing parts of the boundary data of each landslide.

[0053] In a second aspect of the present application, a device for batch extraction of landslide parameters based on DEM is provided, the device comprising:

[0054] An acquisition module is used to acquire boundary data of multiple landslides in a target area, and elevation data corresponding to the boundary data of each landslide;

[0055] A conversion module, used for converting the boundary data of each landslide into a projection coordinate system through projection transformation, and obtaining the three-dimensional coordinates corresponding to the boundary data of each landslide in combination with the elevation data corresponding to the boundary data of each landslide;

[0056] A first determination module is used to determine the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide;

[0057] A second determination module is used to determine the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide according to the target rectangle corresponding to each landslide;

[0058] A first calculation module, used for calculating the three-dimensional coordinates of the midpoints of each side of each target rectangle according to the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide;

[0059] The second calculation module is used to calculate the landslide parameters corresponding to each landslide according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle.

[0060] Optionally, the landslide parameter includes: landslide length, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module includes:

[0061] The first calculation submodule is used to number the multiple landslides in the target area, traverse each landslide in the order of the numbers, and calculate the landslide length of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0062] A first determining subunit is used to determine the Z-axis coordinate value of the midpoint of each side of the target rectangle of the target landslide from the three-dimensional coordinates of the midpoint of each side of the target rectangle of the target landslide;

[0063] A second determining subunit is used to determine the maximum Z-axis coordinate value and the minimum Z-axis coordinate value of the target landslide according to the Z-axis coordinate values ​​of the midpoints of the sides of the target rectangle of the target landslide;

[0064] A third determining subunit is used to determine the maximum Z-axis coordinate value of the midpoints of the target rectangle of the target landslide as the highest point of the target landslide, and determine the minimum Z-axis coordinate value as the lowest point of the target landslide;

[0065] The first calculation subunit is used to calculate the landslide length of the target landslide according to the projection coordinates of the highest point and the projection coordinates of the lowest point.

[0066] Optionally, the landslide parameter includes: landslide width, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module includes:

[0067] The second calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide width of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0068] An acquisition subunit is used to acquire the projection coordinates of two other midpoints of the midpoints of the sides of the target rectangle of the target landslide, except the midpoint corresponding to the maximum Z-axis coordinate value and the midpoint corresponding to the minimum Z-axis coordinate value;

[0069] The second calculation subunit is used to calculate the landslide width of the target landslide according to the projection coordinates of the other two midpoints.

[0070] Optionally, the landslide parameters include: landslide direction, the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module includes:

[0071] The third calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide direction of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0072] A fourth determination subunit is used to determine a target angle between a line connecting the highest point and the lowest point and a preset direction according to the projection coordinates of the highest point and the projection coordinates of the lowest point of the target rectangle of the target landslide;

[0073] A third calculation subunit is used to calculate the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and to calculate the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point;

[0074] The fifth determination subunit is used to determine the landslide direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle.

[0075] Optionally, the determining the slope direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle, the fifth determining subunit includes:

[0076] A sixth determination subunit is used to determine the landslide direction of the target landslide as the sum of the first target angle and the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than or equal to zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than or equal to zero; or

[0077] A seventh determination subunit is used to determine the landslide direction of the target landslide as the difference between the second target angle and the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero; or

[0078] an eighth determination subunit, for determining that the landslide direction of the target landslide is the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero; or

[0079] The ninth determination subunit is used to determine that the landslide direction of the target landslide is the difference between the first target angle and the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than zero.

[0080] Optionally, the landslide parameter includes: landslide slope, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module includes:

[0081] The fourth calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide slope of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0082] A fourth calculation subunit is used to calculate the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, respectively, according to the three-dimensional coordinates of the highest point and the three-dimensional coordinates of the lowest point of the target rectangle of the target landslide;

[0083] The fifth calculation subunit is used to calculate the landslide slope of the target landslide according to the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point.

[0084] Optionally, the target rectangle corresponding to each landslide is determined in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide, and the first determination module includes:

[0085] A spatial calculation submodule, for obtaining a plurality of boundary circumscribed rectangles of the landslide by spatial calculation in the projection coordinate system according to the three-dimensional coordinates of the boundary data of any of the landslides;

[0086] A comparison submodule, configured to determine a boundary circumscribed rectangle with the smallest width among the plurality of boundary circumscribed rectangles by comparing the plurality of boundary circumscribed rectangles in pairs;

[0087] The first determination submodule is used to determine the bounding rectangle of the minimum width as the target rectangle.

[0088] Optionally, the landslide parameters include: landslide representative points, the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module includes:

[0089] The fifth calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the representative point of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0090] The sixth calculation subunit is used to calculate the representative point of the target landslide based on the projection coordinates of the highest point and the projection coordinates of the lowest point, wherein the representative point of the target landslide is located at half of the line connecting the highest point and the lowest point, or the representative point of the target landslide is located at two-thirds of the line connecting the lowest point to the highest point.

[0091] Optionally, the boundary data of each landslide is converted into a projection coordinate system through projection transformation, and the conversion module includes:

[0092] An acquisition submodule is used to acquire the original coordinate system corresponding to the boundary data of each landslide and the geographical location of the target area;

[0093] A second determination submodule is used to determine a projection coordinate system corresponding to the target area according to the geographical location of the target area;

[0094] The coordinate conversion submodule is used to convert the boundary data of each landslide from the original coordinate system to the projection coordinate system through coordinate system conversion according to the projection coordinate system and the original coordinate system corresponding to the boundary data of each landslide.

[0095] In a third aspect of the present application, a computer program product is provided, comprising a memory, a processor and a computer program stored in the memory, wherein the processor executes the computer program to implement a method for batch extraction of landslide parameters based on DEM as described in the first aspect of the present application.

[0096] Beneficial effects of this application:

[0097] The embodiment of the present application provides a method for batch extraction of landslide parameters based on DEM, the method comprising: obtaining boundary data of multiple landslides in a target area, and elevation data corresponding to the boundary data of each landslide; converting the boundary data of each landslide to a projection coordinate system through projection transformation, and obtaining the three-dimensional coordinates corresponding to the boundary data of each landslide in combination with the elevation data corresponding to the boundary data of each landslide; determining the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide; determining the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide according to the target rectangle corresponding to each landslide; calculating the three-dimensional coordinates of the midpoint of each side of each target rectangle according to the three-dimensional coordinates of the midpoint of each side of each target rectangle; and calculating the landslide parameters corresponding to each landslide according to the three-dimensional coordinates of the midpoint of each side of each target rectangle.

[0098] This application converts the boundary data of batch landslides into a unified projection coordinate system and combines it with elevation data to obtain the target rectangle of each landslide, and then calculates the landslide parameters of each landslide through the target rectangle. This application greatly improves the efficiency of landslide parameter extraction and reduces the workload of manual measurement. It is suitable for batch processing of landslide parameters in large-scale landslide databases. Through automated calculation and batch processing, key parameters can be obtained quickly and accurately, improving the accuracy and efficiency of landslide analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0099] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0100] Figure 1 It is a schematic diagram of the steps of a method for batch extraction of landslide parameters based on DEM provided in an embodiment of the present application;

[0101] Figure 2 is a schematic diagram of the distribution of the width to length ratio of each landslide in a target area provided in an embodiment of the present application;

[0102] Figure 3 It is a schematic diagram of the distribution of landslide slope directions of various landslides in a target area provided by an embodiment of the present application;

[0103] Figure 4It is a schematic diagram of landslide slope calculation provided in an embodiment of the present application;

[0104] Figure 5 It is a schematic diagram of the distribution of landslide slopes of various landslides in a target area provided in an embodiment of the present application;

[0105] Figure 6 It is a schematic diagram of the minimum circumscribed rectangle of a landslide boundary provided in an embodiment of the present application;

[0106] Figure 7 It is a schematic diagram of a device for batch extraction of landslide parameters based on DEM provided in an embodiment of the present application;

[0107] Figure 8 It is a schematic diagram of a computer program product provided in an embodiment of the present application. DETAILED DESCRIPTION

[0108] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings in the embodiments of the present application. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to enable the scope of the present application to be fully communicated to those skilled in the art.

[0109] Based on the above problems, in the first aspect of the embodiment of the present application, a method for batch extraction of landslide parameters based on DEM is provided, such as Figure 1 As shown, the method includes:

[0110] Step S101, obtaining boundary data of multiple landslides in a target area, and elevation data corresponding to the boundary data of each landslide;

[0111] In this step, first, the boundary data of multiple landslides in the target area and the elevation data corresponding to each landslide boundary data are obtained. In practical applications, the DEM (Digital Elevation Model) data of the landslide database range can be obtained by downloading open source databases, measuring with drones, or obtaining data from surveying and mapping departments, and the coordinate system of these data must be consistent.

[0112] Specifically, the landslide boundary data defines the boundary contour of the landslide area. This application can be obtained through remote sensing image interpretation, drone mapping, and existing database extraction. Among them, remote sensing image interpretation is to use high-resolution satellite images or aerial images to determine the boundary of the landslide through manual or automatic interpretation methods; drone mapping is to use drones equipped with high-precision cameras or lidars to take aerial photos or laser scans of the landslide area, and obtain landslide boundary data through image processing or point cloud data analysis. Existing database acquisition is to use the landslide boundary data stored in the existing geological disaster database or geographic information system. These data can come from previous surveys and studies and are a quick way to obtain landslide boundary data.

[0113] For the elevation data corresponding to each landslide boundary, high-resolution DEM data can be used to obtain the elevation data of the landslide boundary points. The DEM data can be obtained through public data sources, from professional surveying and mapping agencies, or through methods such as drones, aerial photography, or ground-based lidar.

[0114] In this step, by acquiring landslide boundary and elevation data in batches, the consistency and reliability of the data are ensured, large-scale landslide analysis is supported, manual workload is reduced, data accuracy is improved, and a solid foundation is provided for subsequent three-dimensional coordinate calculation and landslide parameter extraction.

[0115] Step S102, converting the boundary data of each landslide into a projection coordinate system through projection transformation, and combining the elevation data corresponding to each boundary data of each landslide to obtain the three-dimensional coordinates corresponding to each boundary data of each landslide;

[0116] In this step, the boundary data of the landslide is converted to a standard projection coordinate system through projection transformation. Because the boundary data of the landslide is usually in a geographic coordinate system, through projection transformation, the boundary data of multiple landslide boundaries can be converted from the geographic coordinate system to a unified projection coordinate system for further analysis.

[0117] Furthermore, after obtaining the transformed projection coordinates, the projection coordinates of each landslide boundary point are combined with its corresponding elevation data in combination with the elevation data of the landslide, thereby obtaining the three-dimensional coordinates of each landslide boundary point.

[0118] Step S103, determining the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide;

[0119] In this step, the target rectangle corresponding to each landslide is determined in the projection coordinate system according to the three-dimensional coordinates of the boundary data of each landslide. In this embodiment, the target rectangle of each landslide is the minimum circumscribed rectangle of each landslide boundary.

[0120] Step S104, determining the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide according to the target rectangle corresponding to each landslide;

[0121] In this step, according to the target rectangle corresponding to each landslide determined in step S103, the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide, ie, the three-dimensional coordinates of the four corner points of the target rectangle, are determined.

[0122] Step S105, calculating the three-dimensional coordinates of the midpoints of the sides of each target rectangle according to the three-dimensional coordinates of the corner points of the target rectangle corresponding to each landslide;

[0123] In this step, according to the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide, the three-dimensional coordinates of the midpoint of each side of each target rectangle can be obtained by the median calculation formula.

[0124] Step S106: calculating the landslide parameters corresponding to each landslide according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle.

[0125] In this step, the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle. In this application, the landslide parameters are specifically: landslide length, landslide width, landslide direction and landslide slope.

[0126] This application converts the boundary data of batch landslides into a unified projection coordinate system and combines it with elevation data to obtain the target rectangle of each landslide, and then calculates the landslide parameters of each landslide through the target rectangle. This application greatly improves the efficiency of landslide parameter extraction and reduces the workload of manual measurement. It is suitable for batch processing of landslide parameters in large-scale landslide databases. Through automated calculation and batch processing, key parameters can be obtained quickly and accurately, improving the accuracy and efficiency of landslide analysis.

[0127] In a preferred embodiment, the landslide parameters include: landslide length, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0128] The multiple landslides in the target area are numbered, each landslide is traversed in the order of the numbers, and the landslide length of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows:

[0129] Determine the Z-axis coordinate value of the midpoint of each side of the target rectangle of the target landslide from the three-dimensional coordinates of the midpoint of each side of the target rectangle of the target landslide;

[0130] Determine the maximum Z-axis coordinate value and the minimum Z-axis coordinate value of the target landslide according to the Z-axis coordinate values ​​of the midpoints of the respective sides of the target rectangle of the target landslide;

[0131] The maximum Z-axis coordinate value of the midpoints of the target rectangle of the target landslide is determined as the highest point of the target landslide, and the minimum Z-axis coordinate value is determined as the lowest point of the target landslide;

[0132] The landslide length of the target landslide is calculated according to the projection coordinates of the highest point and the projection coordinates of the lowest point.

[0133] Specifically, in this embodiment, it is first necessary to number the multiple landslides in the target area, which helps to orderly traverse and identify each landslide in subsequent processing.

[0134] Furthermore, each landslide is traversed in sequence according to the numbering sequence. In each traversal process, the landslide length of the landslide is calculated. Herein, one traversal is taken as an example for explanation, and the specific steps are as follows:

[0135] For the target rectangle of the target landslide in this traversal, the Z-axis coordinate values ​​of the midpoints of each side are obtained to determine the Z-axis coordinate values ​​of these midpoints. According to the Z-axis coordinate values ​​of the midpoints of each side of the target rectangle, the maximum Z-axis coordinate value and the minimum Z-axis coordinate value are found. The midpoint corresponding to the maximum Z-axis coordinate value is represented as the highest point of the landslide, and the midpoint corresponding to the minimum Z-axis coordinate value is represented as the lowest point of the landslide.

[0136] Furthermore, after determining the highest point and the lowest point of the target landslide, the landslide length of the target landslide is calculated according to the projection coordinates of the highest point and the lowest point of the target landslide by the following formula (1):

[0137] (1)

[0138] in, represents the length of the landslide; Represents the projection coordinates of the highest point; Represents the projected coordinates of the lowest point.

[0139] Furthermore, in each traversal process, the landslide length of the target landslide in the traversal process is calculated respectively, so as to obtain the batch landslide lengths of multiple landslides in the target area. In practical applications, after obtaining the batch landslide lengths of multiple landslides in the target area, the batch landslide length data can be stored in a preset attribute field in a preset database.

[0140] In a preferred embodiment, the landslide parameters include: landslide width, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0141] Each landslide is traversed in the order of the numbers, and the landslide width of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows:

[0142] Obtaining the projection coordinates of two other midpoints of the midpoints of the target rectangle of the target landslide, except for the midpoint corresponding to the maximum Z-axis coordinate value and the midpoint corresponding to the minimum Z-axis coordinate value;

[0143] The landslide width of the target landslide is calculated according to the projection coordinates of the other two midpoints.

[0144] Specifically, in this embodiment, each landslide is traversed in sequence according to the numbering order. In each traversal process, the landslide width of the landslide is calculated. This embodiment is still described by taking one traversal as an example, and the specific steps are as follows:

[0145] For the target rectangle of the target landslide in this traversal, the Z-axis coordinate values ​​of the midpoints of each side are obtained to determine the Z-axis coordinate values ​​of these midpoints. Among them, the maximum Z-axis coordinate value and the minimum Z-axis coordinate value have been used to calculate the length of the landslide. This embodiment obtains the projection coordinates of the remaining two midpoints, and calculates the landslide width of the target landslide based on the projection coordinates of the two midpoints by the following formula (2):

[0146] (2)

[0147] in, represents the width of the landslide; , Respectively represent the projection coordinates of the other two midpoints in the target rectangle except the highest point and the lowest point.

[0148] Furthermore, in each traversal process, the landslide width of the target landslide in the traversal process is calculated respectively, so as to obtain the batch landslide widths of multiple landslides in the target area. In practical applications, after obtaining the batch landslide widths of multiple landslides in the target area, the batch landslide width data can be stored in a preset attribute field in a preset database.

[0149] In one embodiment, if Figure 2 FIG. 1 is a schematic diagram showing the distribution of the width and length ratios of the landslides in a target area according to an embodiment of the present application. Figure 2 It can be seen from the figure that the distribution of the width-to-length ratios of the landslides in the target area.

[0150] In a preferred embodiment, the landslide parameters include: landslide direction, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0151] Traverse each landslide in the order of the numbers, and calculate the landslide direction of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0152] Determine a target angle between a line connecting the highest point and the lowest point and a preset direction according to the projection coordinates of the highest point and the projection coordinates of the lowest point of the target rectangle of the target landslide;

[0153] Calculate the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and calculate the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point;

[0154] The landslide direction of the target landslide is determined according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle.

[0155] Specifically, in this embodiment, each landslide is traversed in sequence according to the numbering order. In each traversal process, the landslide slope direction of the landslide is calculated. This embodiment is still described by taking one traversal as an example, and the specific steps are as follows:

[0156] For the target rectangle of the target landslide in this traversal, the projection coordinates of the highest point and the lowest point of the target rectangle of the target landslide are obtained, and the angle between the line between the highest point and the lowest point and the preset direction is determined. In practical applications, the preset direction is usually due north. The calculation formula (3) of the target angle is as follows:

[0157] (3)

[0158] in, Indicates the target angle.

[0159] Further, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is calculated, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is calculated;

[0160] The slope direction of the target landslide is determined according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle.

[0161] Furthermore, in each traversal process, the landslide direction of the target landslide in the traversal process is calculated respectively, so as to obtain the batch landslide directions of multiple landslides in the target area. In practical applications, after obtaining the batch landslide directions of multiple landslides in the target area, the batch landslide direction data can be stored in a preset attribute field in a preset database.

[0162] In one embodiment, there is provided a Figure 3 A schematic diagram of the distribution of landslide slope directions of various landslides in the target area is shown in FIG. Figure 3 The distribution of landslide slope directions of various landslides in the target area can be seen in the figure.

[0163] In a preferred embodiment, determining the slope direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle comprises:

[0164] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than or equal to zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than or equal to zero, then the slope direction of the target landslide is determined to be the sum of the first target angle and the target angle; or,

[0165] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero, then the slope direction of the target landslide is determined to be the difference between the second target angle and the target angle; or,

[0166] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero, then the slope direction of the target landslide is determined to be the target angle; or,

[0167] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than zero, then the slope direction of the target landslide is determined to be the difference between the first target angle and the target angle.

[0168] Specifically, if Figure 4 As shown, a landslide slope direction calculation schematic diagram provided by this embodiment, as shown in the figure, rectangle ABCD is the target rectangle, the boundary area within rectangle ABCD is the boundary of the target landslide, and the target angle is ,according to Figure 4 As shown:

[0169] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than or equal to zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than or equal to zero, then the slope direction of the target landslide is determined to be the sum of the first target angle and the target angle; or,

[0170] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero, then the slope direction of the target landslide is determined to be the difference between the second target angle and the target angle; or,

[0171] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero, then the slope direction of the target landslide is determined to be the target angle; or,

[0172] If the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than zero, then the slope direction of the target landslide is determined to be the difference between the first target angle and the target angle.

[0173] The slope aspect formula (4) of the target landslide is as follows:

[0174] (4)

[0175] in, Indicates the slope direction of the landslide.

[0176] In a preferred embodiment, the landslide parameters include: landslide slope, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including:

[0177] Traverse each landslide in the order of the numbers, and calculate the landslide slope of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0178] According to the three-dimensional coordinates of the highest point and the three-dimensional coordinates of the lowest point of the target rectangle of the target landslide, respectively calculate the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point;

[0179] The landslide slope of the target landslide is calculated based on the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point.

[0180] Specifically, in this embodiment, each landslide is traversed in sequence according to the numbering order. In each traversal process, the landslide slope of the landslide is calculated. This embodiment is still described by taking one traversal as an example, and the specific steps are as follows:

[0181] For the target rectangle of the target landslide in this traversal, according to the three-dimensional coordinates of the highest point and the lowest point of the target rectangle of the target landslide, the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point are calculated respectively;

[0182] The landslide slope of the target landslide is calculated based on the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point. The calculation formula (5) of the landslide slope is as follows:

[0183] (5)

[0184] in, Indicates the slope of the landslide.

[0185] Furthermore, in each traversal process, the landslide slope of the target landslide in the traversal process is calculated respectively, so as to obtain the batch landslide slopes of multiple landslides in the target area. In practical applications, after obtaining the batch landslide slopes of multiple landslides in the target area, the batch landslide slope data can be stored in a preset attribute field in a preset database.

[0186] In one embodiment, there is provided Figure 5 A schematic diagram of the distribution of landslide slopes in the target area is shown in FIG. Figure 5 The distribution of landslide slopes of various landslides in the target area can be seen in the figure.

[0187] In a preferred embodiment, determining the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide respectively includes:

[0188] According to the three-dimensional coordinates of the boundary data of any of the landslides, a plurality of boundary circumscribed rectangles of the landslide are obtained by spatial calculation in the projection coordinate system;

[0189] By comparing the plurality of bounding rectangles in pairs, determining a bounding rectangle with the smallest width among the plurality of bounding rectangles;

[0190] The bounding rectangle of the minimum width is determined as the target rectangle.

[0191] Specifically, in this embodiment, the target rectangle for any target landslide is determined by the following steps: First, according to the three-dimensional coordinates of the boundary data of the target landslide, spatial calculation is performed in the projection coordinate system to obtain multiple boundary circumscribed rectangles. Next, these boundary circumscribed rectangles are compared in pairs to calculate their widths and heights. Then, the rectangle with the smallest width is selected from all boundary circumscribed rectangles as the final target rectangle. This process ensures that the selected rectangle can accurately cover the actual boundary of the landslide and most effectively represent the scope of the landslide in the two-dimensional projection coordinate system. For details, please refer to the following. Figure 6 The figure shows a schematic diagram of the minimum circumscribed rectangle of a landslide boundary, where rectangle ABCD is the minimum circumscribed rectangle of the landslide.

[0192] In a preferred embodiment, the landslide parameters include: representative points of the landslide, and the landslide parameters corresponding to each landslide are calculated based on the three-dimensional coordinates of the midpoints of the sides of each target rectangle, including:

[0193] Traverse each landslide in the order of the numbers, and calculate the representative points of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0194] The representative point of the target landslide is calculated based on the projection coordinates of the highest point and the projection coordinates of the lowest point, wherein the representative point of the target landslide is located at half of the line connecting the highest point and the lowest point, or the representative point of the target landslide is located at two-thirds of the line connecting the highest point and the lowest point.

[0195] Specifically, in this embodiment, in order to simplify the description of the landslide, the present application uses representative points of the landslide to represent the landslide. In this embodiment, each landslide is traversed in sequence according to the numbering order. In each traversal process, the representative points of the landslide are calculated. This embodiment is still described by taking one traversal as an example, and the specific steps are as follows:

[0196] The projection coordinates of the highest point and the lowest point of the target landslide in this traversal process are obtained, and the representative point of the target landslide is obtained by calculation, wherein the representative point of the target landslide is located at one-half of the line connecting the highest point and the lowest point of the target landslide, or at two-thirds of the line connecting the lowest point to the highest point of the target landslide. In actual applications, the representative point of the target landslide can also be located at any preset position according to requirements, which is not specifically limited in this embodiment.

[0197] In a preferred embodiment, the step of converting the boundary data of each landslide into a projection coordinate system through projection transformation comprises:

[0198] Obtaining the original coordinate system corresponding to the boundary data of each landslide and the geographical location of the target area;

[0199] Determine a projection coordinate system corresponding to the target area according to the geographical location of the target area;

[0200] According to the projection coordinate system and the original coordinate system corresponding to the boundary data of each landslide, the boundary data of each landslide is converted from the original coordinate system to the projection coordinate system through coordinate system conversion.

[0201] Specifically, in this embodiment, first, the original coordinate system corresponding to the boundary data of each landslide and the geographical location of the target area are obtained. These data are the basis for projection transformation. In practical applications, the original coordinate system corresponding to the boundary data of each landslide is usually a geographical coordinate system.

[0202] Furthermore, according to the geographical location of the target area, a projection coordinate system corresponding to the area is determined. The projection coordinate system is a plane coordinate system defined for the target area and is used to convert geographic space data into plane coordinate data.

[0203] Furthermore, according to the projection coordinate system and the original coordinate system corresponding to the boundary data of each landslide, the boundary data of the landslide is converted from the original coordinate system to the projection coordinate system through the coordinate system conversion method. This step ensures that the landslide data can be analyzed and processed in a unified plane coordinate system.

[0204] In a preferred embodiment, before converting the boundary data of each landslide from the original coordinate system to the projected coordinate system, the method further comprises:

[0205] The coordinate consistency correction is performed on the boundary data of each landslide.

[0206] Specifically, in this embodiment, after obtaining the boundary data of each landslide, it is necessary to perform coordinate consistency correction on the boundary data of each landslide. In practical applications, the coordinate consistency correction may include: Error correction: Eliminate coordinate deviations caused by measuring equipment, recording errors or data conversion. This can be adjusted using reference points or known coordinates; Data alignment: Ensure that the boundary data of all landslides are aligned in the same original coordinate system. If the boundary data of different landslides come from different measurement methods or times, alignment adjustments are required. Data smoothing: Smooth the coordinate data to eliminate abnormal fluctuations caused by noise or irregular measurement points, making the boundaries more continuous and smooth. Projection adjustment: Within the original coordinate system, the data needs to be adjusted to adapt to the expected projection transformation to ensure that the converted data remains consistent in the new coordinate system.

[0207] In a preferred embodiment, after obtaining boundary data of a plurality of landslides in the target area, the method further comprises:

[0208] Preprocess the boundary data of each landslide separately;

[0209] The pre-processing measures include: filtering the boundary data of each landslide, or using a difference algorithm to supplement the missing parts of the boundary data of each landslide.

[0210] Specifically, after obtaining the boundary data of multiple landslides in the target area, it is necessary to preprocess the boundary data of these landslides. In practical applications, the preprocessing measures may include: Filtering: Filtering the boundary data of each landslide. This step is mainly used to eliminate noise or abnormal points in the data, smooth the data curve, and make the boundary line more continuous and accurate. Different filtering algorithms can be used for filtering, such as mean filtering, Kalman filtering, low-pass filtering, etc., and the appropriate filtering method is selected according to specific needs; Difference algorithm supplements missing data: For the missing parts in the landslide boundary data, the difference algorithm is used to supplement them. The difference algorithm can infer the missing part of the data through the existing boundary data points, thereby filling the gaps in the data and ensuring the integrity of the boundary. Common difference algorithms include linear interpolation, spline interpolation, Lagrange interpolation, etc.

[0211] The embodiment of the present application provides a method for batch extraction of landslide parameters based on DEM, the method comprising: obtaining boundary data of multiple landslides in a target area, and elevation data corresponding to the boundary data of each landslide; converting the boundary data of each landslide to a projection coordinate system through projection transformation, and obtaining the three-dimensional coordinates corresponding to the boundary data of each landslide in combination with the elevation data corresponding to the boundary data of each landslide; determining the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide; determining the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide according to the target rectangle corresponding to each landslide; calculating the three-dimensional coordinates of the midpoint of each side of each target rectangle according to the three-dimensional coordinates of the midpoint of each side of each target rectangle; and calculating the landslide parameters corresponding to each landslide according to the three-dimensional coordinates of the midpoint of each side of each target rectangle.

[0212] This application converts the boundary data of batch landslides into a unified projection coordinate system and combines it with elevation data to obtain the target rectangle of each landslide, and then calculates the landslide parameters of each landslide through the target rectangle. This application greatly improves the efficiency of landslide parameter extraction and reduces the workload of manual measurement. It is suitable for batch processing of landslide parameters in large-scale landslide databases. Through automated calculation and batch processing, key parameters can be obtained quickly and accurately, improving the accuracy and efficiency of landslide analysis.

[0213] Based on the same inventive concept, in a second aspect of the embodiment of the present application, a device for batch extraction of landslide parameters based on DEM is provided, such as Figure 7 As shown, the device comprises:

[0214] An acquisition module 201 is used to acquire boundary data of multiple landslides in a target area, and elevation data corresponding to the boundary data of each landslide;

[0215] The conversion module 202 is used to convert the boundary data of each landslide into a projection coordinate system through projection transformation, and obtain the three-dimensional coordinates corresponding to the boundary data of each landslide in combination with the elevation data corresponding to the boundary data of each landslide;

[0216] A first determination module 203 is used to determine the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide;

[0217] The second determination module 204 is used to determine the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide according to the target rectangle corresponding to each landslide;

[0218] The first calculation module 205 is used to calculate the three-dimensional coordinates of the midpoints of each side of each target rectangle according to the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide;

[0219] The second calculation module 206 is used to calculate the landslide parameters corresponding to each landslide according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle.

[0220] Optionally, the landslide parameter includes: landslide length, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module 206 includes:

[0221] The first calculation submodule is used to number the multiple landslides in the target area, traverse each landslide in the order of the numbers, and calculate the landslide length of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows:

[0222] A first determining subunit is used to determine the Z-axis coordinate value of the midpoint of each side of the target rectangle of the target landslide from the three-dimensional coordinates of the midpoint of each side of the target rectangle of the target landslide;

[0223] A second determining subunit is used to determine the maximum Z-axis coordinate value and the minimum Z-axis coordinate value of the target landslide according to the Z-axis coordinate values ​​of the midpoints of the sides of the target rectangle of the target landslide;

[0224] A third determining subunit is used to determine the maximum Z-axis coordinate value of the midpoints of the target rectangle of the target landslide as the highest point of the target landslide, and determine the minimum Z-axis coordinate value as the lowest point of the target landslide;

[0225] The first calculation subunit is used to calculate the landslide length of the target landslide according to the projection coordinates of the highest point and the projection coordinates of the lowest point.

[0226] Optionally, the landslide parameter includes landslide width. The landslide parameter corresponding to each landslide is calculated based on the three-dimensional coordinates of the midpoints of each side of each target rectangle. The second calculation module 206 includes:

[0227] The second calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide width of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0228] An acquisition subunit is used to acquire the projection coordinates of two other midpoints of the midpoints of the sides of the target rectangle of the target landslide, except the midpoint corresponding to the maximum Z-axis coordinate value and the midpoint corresponding to the minimum Z-axis coordinate value;

[0229] The second calculation subunit is used to calculate the landslide width of the target landslide according to the projection coordinates of the other two midpoints.

[0230] Optionally, the landslide parameters include: landslide direction, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle. The second calculation module 206 includes:

[0231] The third calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide direction of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0232] A fourth determination subunit is used to determine a target angle between a line connecting the highest point and the lowest point and a preset direction according to the projection coordinates of the highest point and the projection coordinates of the lowest point of the target rectangle of the target landslide;

[0233] A third calculation subunit is used to calculate the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and to calculate the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point;

[0234] The fifth determination subunit is used to determine the landslide direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle.

[0235] Optionally, the determining the slope direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle, the fifth determining subunit includes:

[0236] A sixth determination subunit is used to determine the landslide direction of the target landslide as the sum of the first target angle and the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than or equal to zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than or equal to zero; or

[0237] A seventh determination subunit is used to determine the landslide direction of the target landslide as the difference between the second target angle and the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is greater than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero; or

[0238] an eighth determination subunit, for determining that the landslide direction of the target landslide is the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is less than zero; or

[0239] The ninth determination subunit is used to determine that the landslide direction of the target landslide is the difference between the first target angle and the target angle if the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point is less than zero, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point is greater than zero.

[0240] Optionally, the landslide parameter includes: landslide slope, and the landslide parameter corresponding to each landslide is calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, and the second calculation module 206 includes:

[0241] The fourth calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide slope of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0242] A fourth calculation subunit is used to calculate the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, respectively, according to the three-dimensional coordinates of the highest point and the three-dimensional coordinates of the lowest point of the target rectangle of the target landslide;

[0243] The fifth calculation subunit is used to calculate the landslide slope of the target landslide according to the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point.

[0244] Optionally, according to the three-dimensional coordinates corresponding to the boundary data of each landslide, in the projection coordinate system, the target rectangle corresponding to each landslide is determined respectively, and the first determination module 203 includes:

[0245] A spatial calculation submodule, for obtaining a plurality of boundary circumscribed rectangles of the landslide by spatial calculation in the projection coordinate system according to the three-dimensional coordinates of the boundary data of any of the landslides;

[0246] A comparison submodule, configured to determine a boundary circumscribed rectangle with the smallest width among the plurality of boundary circumscribed rectangles by comparing the plurality of boundary circumscribed rectangles in pairs;

[0247] The first determination submodule is used to determine the bounding rectangle of the minimum width as the target rectangle.

[0248] Optionally, the landslide parameters include: landslide representative points, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle. The second calculation module 206 includes:

[0249] The fifth calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the representative point of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows:

[0250] The sixth calculation subunit is used to calculate the representative point of the target landslide based on the projection coordinates of the highest point and the projection coordinates of the lowest point, wherein the representative point of the target landslide is located at half of the line connecting the highest point and the lowest point, or the representative point of the target landslide is located at two-thirds of the line connecting the highest point and the lowest point.

[0251] Optionally, the boundary data of each landslide is converted into a projection coordinate system through projection transformation, and the conversion module 202 includes:

[0252] An acquisition submodule is used to acquire the original coordinate system corresponding to the boundary data of each landslide and the geographical location of the target area;

[0253] A second determination submodule is used to determine a projection coordinate system corresponding to the target area according to the geographical location of the target area;

[0254] The coordinate conversion submodule is used to convert the boundary data of each landslide from the original coordinate system to the projection coordinate system through coordinate system conversion according to the projection coordinate system and the original coordinate system corresponding to the boundary data of each landslide.

[0255] Based on the same inventive concept, in a third aspect of the embodiment of the present application, there is provided a Figure 8The computer program product 100 shown includes a memory 110, a processor 120, and a computer program stored in the memory 110. The processor 120 executes the computer program to implement a method for batch extraction of landslide parameters based on DEM as described in the first aspect of the present application.

[0256] Each embodiment in the specification focuses on the differences from other embodiments, and the same or similar parts between the embodiments can be referenced to each other.

[0257] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, devices, or computer program products. Therefore, the embodiments of the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the embodiments of the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0258] The embodiments of the present application are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0259] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0260] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device so that a series of operating steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for executing on the computer or other programmable terminal device to implement the process. Figure 1 A process or multiple processes and / or boxes Figure 1The steps for the functions specified in one or more boxes.

[0261] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0262] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0263] The above provides a detailed introduction to a method, device and product for batch extraction of landslide parameters based on DEM. In this article, specific examples are used to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for batch extraction of landslide parameters based on DEM, characterized in that: The method comprises: Obtain boundary data of multiple landslides in the target area, and elevation data corresponding to the boundary data of each landslide; The boundary data of each landslide is converted into a projection coordinate system through projection transformation, and the three-dimensional coordinates corresponding to the boundary data of each landslide are obtained in combination with the elevation data corresponding to the boundary data of each landslide; According to the three-dimensional coordinates corresponding to the boundary data of each landslide, in the projection coordinate system, respectively determine the target rectangle corresponding to each landslide, wherein the target rectangle is a rectangle with the smallest width among multiple boundary circumscribed rectangles obtained by spatial calculation in the projection coordinate system according to the three-dimensional coordinates of the boundary data of the landslide; According to the target rectangle corresponding to each landslide, determine the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide; Calculating the three-dimensional coordinates of the midpoints of the sides of each target rectangle according to the three-dimensional coordinates of the corner points of the target rectangle corresponding to each landslide; According to the three-dimensional coordinates of the midpoints of the sides of each target rectangle, the landslide parameters corresponding to each landslide are calculated; The landslide parameters include: landslide direction; the landslide parameters corresponding to each landslide are calculated based on the three-dimensional coordinates of the midpoints of the sides of each target rectangle, including: The multiple landslides in the target area are numbered, each landslide is traversed in the order of the numbers, and the landslide direction of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows: Determine a target angle between a line connecting the highest point and the lowest point and a preset direction according to the projection coordinates of the highest point and the projection coordinates of the lowest point of the target rectangle of the target landslide; Calculate the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and calculate the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point; The slope direction of the target landslide is determined according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle. The slope direction formula of the target landslide is as follows: in, Indicates the slope direction of the landslide; represents the target angle; Represents the projection coordinates of the highest point; Represents the projected coordinates of the lowest point.

2. The method for batch extraction of landslide parameters based on DEM according to claim 1, characterized in that: The landslide parameters include: landslide length, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle, including: The multiple landslides in the target area are numbered, each landslide is traversed in the order of the numbers, and the landslide length of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows: Determine the Z-axis coordinate value of the midpoint of each side of the target rectangle of the target landslide from the three-dimensional coordinates of the midpoint of each side of the target rectangle of the target landslide; Determine the maximum Z-axis coordinate value and the minimum Z-axis coordinate value of the target landslide according to the Z-axis coordinate values ​​of the midpoints of the respective sides of the target rectangle of the target landslide; The maximum Z-axis coordinate value of the midpoints of the target rectangle of the target landslide is determined as the highest point of the target landslide, and the minimum Z-axis coordinate value is determined as the lowest point of the target landslide; The landslide length of the target landslide is calculated according to the projection coordinates of the highest point and the projection coordinates of the lowest point.

3. The method for batch extraction of landslide parameters based on DEM according to claim 2 is characterized in that: The landslide parameters include: landslide width. The landslide parameters corresponding to each landslide are calculated based on the three-dimensional coordinates of the midpoints of the sides of each target rectangle, including: Each landslide is traversed in the order of the numbers, and the landslide width of the target landslide corresponding to the traversal process is calculated in each traversal process, the steps are as follows: Obtaining the projection coordinates of two other midpoints of the midpoints of the target rectangle of the target landslide, except for the midpoint corresponding to the maximum Z-axis coordinate value and the midpoint corresponding to the minimum Z-axis coordinate value; The landslide width of the target landslide is calculated according to the projection coordinates of the other two midpoints.

4. The method for batch extraction of landslide parameters based on DEM according to claim 2 is characterized in that: The landslide parameters include: landslide slope, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of each side of each target rectangle, including: Traverse each landslide in the order of the numbers, and calculate the landslide slope of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows: According to the three-dimensional coordinates of the highest point and the three-dimensional coordinates of the lowest point of the target rectangle of the target landslide, respectively calculate the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point; The landslide slope of the target landslide is calculated based on the difference between the Z-axis coordinate value of the highest point and the Z-axis coordinate value of the lowest point, the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point.

5. The method for batch extraction of landslide parameters based on DEM according to claim 1 is characterized in that: The step of determining the target rectangle corresponding to each landslide in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of each landslide comprises: According to the three-dimensional coordinates of the boundary data of any of the landslides, a plurality of boundary circumscribed rectangles of the landslide are obtained by spatial calculation in the projection coordinate system; By comparing the plurality of bounding rectangles in pairs, determining a bounding rectangle with the smallest width among the plurality of bounding rectangles; The bounding rectangle of the minimum width is determined as the target rectangle.

6. The method for batch extraction of landslide parameters based on DEM according to claim 2, characterized in that: The landslide parameters include: landslide representative points, and the landslide parameters corresponding to each landslide are calculated based on the three-dimensional coordinates of the midpoints of the sides of each target rectangle, including: Traverse each landslide in the order of the numbers, and calculate the representative points of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows: The representative point of the target landslide is calculated based on the projection coordinates of the highest point and the projection coordinates of the lowest point, wherein the representative point of the target landslide is located at half of the line connecting the highest point and the lowest point, or the representative point of the target landslide is located at two-thirds of the line connecting the lowest point to the highest point.

7. The method for batch extraction of landslide parameters based on DEM according to claim 1 is characterized in that: The step of converting the boundary data of each landslide into a projection coordinate system through projection transformation includes: Obtaining the original coordinate system corresponding to the boundary data of each landslide and the geographical location of the target area; Determine a projection coordinate system corresponding to the target area according to the geographical location of the target area; According to the projection coordinate system and the original coordinate system corresponding to the boundary data of each landslide, the boundary data of each landslide is converted from the original coordinate system to the projection coordinate system through coordinate system conversion.

8. The method for batch extraction of landslide parameters based on DEM according to claim 7 is characterized in that: Before converting the boundary data of each landslide from the original coordinate system to the projected coordinate system, the method further includes: The coordinate consistency correction is performed on the boundary data of each landslide.

9. The method for batch extraction of landslide parameters based on DEM according to claim 1, characterized in that: After acquiring boundary data of a plurality of landslides in the target area, the method further comprises: Preprocess the boundary data of each landslide separately; The pre-processing measures include: filtering the boundary data of each landslide, or using a difference algorithm to supplement the missing parts of the boundary data of each landslide.

10. A device for batch extraction of landslide parameters based on DEM, characterized in that: The device comprises: An acquisition module is used to acquire boundary data of multiple landslides in a target area, and elevation data corresponding to the boundary data of each landslide; A conversion module, used for converting the boundary data of each landslide into a projection coordinate system through projection transformation, and obtaining the three-dimensional coordinates corresponding to the boundary data of each landslide in combination with the elevation data corresponding to the boundary data of each landslide; A first determination module is used to determine, in the projection coordinate system, a target rectangle corresponding to each landslide according to the three-dimensional coordinates corresponding to the boundary data of each landslide, wherein the target rectangle is a rectangle with the smallest width among multiple boundary circumscribed rectangles obtained by performing spatial calculation in the projection coordinate system according to the three-dimensional coordinates corresponding to the boundary data of the landslide; A second determination module is used to determine the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide according to the target rectangle corresponding to each landslide; A first calculation module, used for calculating the three-dimensional coordinates of the midpoints of each side of each target rectangle according to the three-dimensional coordinates of each corner point of the target rectangle corresponding to each landslide; A second calculation module is used to calculate the landslide parameters corresponding to each landslide according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle; The landslide parameters include: landslide direction; the landslide parameters corresponding to each landslide are calculated based on the three-dimensional coordinates of the midpoints of the sides of each target rectangle; and the second calculation module includes: The third calculation submodule is to number the multiple landslides in the target area, traverse each landslide in the order of the numbers, and calculate the landslide direction of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows: A fourth determination subunit is used to determine a target angle between a line connecting the highest point and the lowest point and a preset direction according to the projection coordinates of the highest point and the projection coordinates of the lowest point of the target rectangle of the target landslide; A third calculation subunit is used to calculate the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, and to calculate the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point; The fifth determination subunit is used to determine the slope direction of the target landslide according to the difference between the X-axis coordinate value of the highest point and the X-axis coordinate value of the lowest point, the difference between the Y-axis coordinate value of the highest point and the Y-axis coordinate value of the lowest point, and the target angle. The slope direction formula of the target landslide is as follows: in, Indicates the slope direction of the landslide; represents the target angle; Represents the projection coordinates of the highest point; Represents the projected coordinates of the lowest point.

11. The device for batch extraction of landslide parameters based on DEM according to claim 10, characterized in that: The landslide parameters include: landslide length, the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle, and the second calculation module includes: The first calculation submodule is used to number the multiple landslides in the target area, traverse each landslide in the order of the numbers, and calculate the landslide length of the target landslide corresponding to the traversal process in each traversal process, the steps are as follows: A first determining subunit is used to determine the Z-axis coordinate value of the midpoint of each side of the target rectangle of the target landslide from the three-dimensional coordinates of the midpoint of each side of the target rectangle of the target landslide; A second determining subunit is used to determine the maximum Z-axis coordinate value and the minimum Z-axis coordinate value of the target landslide according to the Z-axis coordinate values ​​of the midpoints of the sides of the target rectangle of the target landslide; A third determining subunit is used to determine the maximum Z-axis coordinate value of the midpoints of the target rectangle of the target landslide as the highest point of the target landslide, and determine the minimum Z-axis coordinate value as the lowest point of the target landslide; The first calculation subunit is used to calculate the landslide length of the target landslide according to the projection coordinates of the highest point and the projection coordinates of the lowest point.

12. The device for batch extraction of landslide parameters based on DEM according to claim 11, characterized in that: The landslide parameters include: landslide width, and the landslide parameters corresponding to each landslide are calculated according to the three-dimensional coordinates of the midpoints of the sides of each target rectangle. The second calculation module includes: The second calculation submodule is used to traverse each landslide in the order of the numbers, and calculate the landslide width of the target landslide corresponding to the traversal process in each traversal process, and the steps are as follows: An acquisition subunit is used to acquire the projection coordinates of two other midpoints of the midpoints of the sides of the target rectangle of the target landslide, except the midpoint corresponding to the maximum Z-axis coordinate value and the midpoint corresponding to the minimum Z-axis coordinate value; The second calculation subunit is used to calculate the landslide width of the target landslide according to the projection coordinates of the other two midpoints.

13. A computer program product, comprising a memory, a processor and a computer program stored in the memory, characterized in that: The processor executes the computer program to implement a method for batch extraction of landslide parameters based on DEM as described in any one of claims 1-9.

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