Topographic mapping method and system based on aerial mapping technology

Abstract

The present invention discloses a terrain surveying and mapping method and system based on aerial surveying and mapping technology, which relates to the field of aerial surveying and mapping technology, including planning the route of the first aerial photography according to the basic information of the area to be surveyed and the aircraft information, setting the flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be surveyed, the aircraft information and the meteorological data, ensuring the reliability of the first aerial photography, and providing a reliable basis for the subsequent second aerial photography. The initial terrain model is established in combination with the regional control points and the geographic image film conditions to improve the stability of the initial surveying and mapping. The geographic image quality and terrain conversion accuracy of each partial area are evaluated, and the route, flight information and photographic equipment information of the second aerial photography are set for the unqualified partial areas, so as to improve the effect of the second aerial photography, thereby updating and improving the terrain model of the area to be surveyed and improving the adaptability of terrain surveying and mapping.

Description

Technical Field

[0001] The present invention relates to the field of aerial surveying and mapping technology, and in particular to a terrain surveying and mapping method and system based on aerial surveying and mapping technology. Background Art

[0002] Topographic mapping of aerial surveying technology mainly relies on aerial photogrammetry technology. This technology installs aerial photographic instruments on aircraft in the atmosphere to continuously photograph the ground and then draw topographic maps. With the advent of the digital age, traditional film cameras have gradually been replaced by high-precision digital aerial cameras (such as DMC). These digital camera systems can adapt to different light conditions and ensure the quality of surveying and mapping images. In addition, the application of new technologies such as big data analysis and artificial intelligence has further improved the accuracy and efficiency of aerial surveying. These technologies not only reduce the layout of ground control points, but also enable surveying and mapping work in difficult areas. Therefore, the terrain surveying scheme based on aerial surveying technology has broad application prospects in engineering construction, exploration of unknown areas and other fields due to its high efficiency and accuracy.

[0003] In the prior art, the terrain for aerial mapping is often acquired through a single aerial photography. However, during the single aerial photography, the reliability and accuracy of the image data collected are low, resulting in poor accuracy and adaptability of terrain mapping.

[0004] Therefore, how to improve the accuracy and adaptability of terrain surveying and mapping is a technical problem that needs to be solved. Summary of the invention

[0005] The purpose of the present invention is to solve the problem of poor accuracy and adaptability of terrain mapping in the prior art, and to propose a terrain mapping method based on aerial mapping technology, which includes:

[0006] Obtain preliminary exploration information of the area to be measured, determine basic information of the area to be measured and regional control points within the area to be measured based on the preliminary exploration information of the area to be measured, obtain aircraft information for implementing aerial flight operations and surveying and mapping requirements of the area to be measured, and plan the first aerial photography route based on the basic information of the area to be measured and aircraft information;

[0007] Acquire meteorological data of the area to be measured, set flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, surveying and mapping requirements of the area to be measured, aircraft information and meteorological data, form a first aerial photography mission by integrating the route, flight information and photographic equipment information of the first aerial photography, collect geographic image data of the area to be measured through the first aerial photography mission, record it as first geographic image data, and generate an initial terrain model of the area to be measured by analyzing the first geographic image data based on regional control points in the area to be measured;

[0008] The area to be tested is divided into regions according to geographical features through the initial terrain model to obtain multiple partial regions, and the geographic image quality and terrain conversion accuracy in each partial region are evaluated, so as to screen out unqualified partial regions, and the route, flight information and photographic equipment information of the second aerial photography are set for the unqualified partial regions, and the route, flight information and photographic equipment information of the second aerial photography are integrated to form a second aerial photography mission, and the geographic image data of the unqualified partial regions are re-collected through the second aerial photography mission, which is recorded as the second geographic image data;

[0009] The second geographic image data is analyzed to update all unqualified partial areas, thereby updating and improving the initial terrain model of the area to be tested, and the updated and improved terrain model is visualized and marked accordingly.

[0010] In some embodiments of the present application, the route of the first aerial photography is planned according to the basic information of the area to be measured and the aircraft information, including:

[0011] All routes are planned based on the basic information of the area to be measured and the aircraft information, and the flight information of the aircraft on each route is preliminarily determined. The basic information of the photographic equipment is obtained, and the shooting range and image overlap of the photographic equipment are determined based on the basic information of the photographic equipment and the preliminary range of the flight information. The optimal route is screened out from all routes based on the shooting range and image overlap of the photographic equipment, and the optimal route is used as the route for the first aerial photography.

[0012] In some embodiments of the present application, the flight information and photographic equipment information of the first aerial photography are set according to the route of the first aerial photography, the surveying and mapping requirements of the area to be surveyed, the aircraft information and the meteorological data, including:

[0013] Matching the meteorological data with the route of the first aerial photography, determining the meteorological data at each position in the route of the first aerial photography, determining a first flight information range in the preliminary range of flight information in combination with the meteorological data and aircraft information, determining a second flight information range in the preliminary range of flight information according to the surveying and mapping requirements of the area to be surveyed, and setting the intersection of the first flight information range and the second flight information range as the flight information of the first aerial photography;

[0014] The photographic equipment information for the first aerial photography is determined based on the meteorological data, the surveying and mapping requirements of the area to be surveyed, and the flight information of the first aerial photography.

[0015] In some embodiments of the present application, the initial terrain model of the area to be measured is generated by analyzing the first geographic image data based on the regional control points in the area to be measured, including:

[0016] The first geographic image data is a plurality of images of the area to be measured arranged in a plurality of time sequences, each image of the area to be measured is preprocessed, a plurality of feature points are extracted from each image of the area to be measured, the feature points between adjacent images of the area to be measured are matched to form connection points, the plurality of images of the area to be measured are connected through the connection points, an importance index of each connection point is determined, the connection points are sorted according to the importance index, and a connection point sorting list is generated;

[0017] The area to be tested is divided into a plurality of sub-areas, and each sub-area is matched with a plurality of images of the area to be tested, and the control point density index of each sub-area is determined according to the regional control points in the area to be tested, and the number of encrypted point targets in each sub-area is determined by combining the control point density index and the image overlap between the plurality of images of the area to be tested, and some connection points are selected as encryption points in the connection point sorting list according to the number of encrypted point targets;

[0018] The image point coordinates of the regional control points in the area to be tested are identified in multiple images of the area to be tested, and the encrypted points are solved and the orientation elements of the images of the area to be tested are determined based on the image point coordinates of the regional control points and the actual coordinates, so as to help generate the initial terrain model of the area to be tested.

[0019] In some embodiments of the present application, the importance index of each connection point is determined, including:

[0020] The unmatched feature points between the images of the area to be tested are recorded as calibration points, the stability of each connection point is evaluated, the surrounding range of each connection point is mapped according to the stability, the number of calibration points and other connection points in the surrounding range are counted, and the importance index of the connection point is determined according to the number of calibration points and other connection points;

[0021] ;

[0022] in, is the importance index of the i-th connection point, is the conversion coefficient corresponding to the calibration point of the i-th connection point, is the number of calibration points around the i-th connection point, is the conversion coefficient of the other connection points of the ith connection point, is the number of other connection points within the vicinity of the i-th connection point.

[0023] In some embodiments of the present application, the area to be measured is divided into regions according to geographical features using an initial terrain model to obtain multiple partial regions, including:

[0024] Determine each geographic feature and position on the area to be tested based on the initial terrain model, integrate all geographic features to generate comprehensive geographic feature indicators, divide the area to be tested into multiple small areas according to its size, and integrate adjacent small areas through comprehensive geographic feature indicators to obtain multiple partial areas.

[0025] In some embodiments of the present application, the geographic image quality and terrain conversion accuracy of each partial area are evaluated to screen out unqualified partial areas, including:

[0026] Determine the image features of each partial area, normalize the image features, evaluate the geographic error features of each partial area, determine the geographic image quality based on the image features, and determine the terrain conversion accuracy based on the geographic error features;

[0027] The screening index is generated by combining the geographic image quality and terrain conversion accuracy, and unqualified areas are screened out based on the screening index;

[0028] ;

[0029] in, is the screening index for the region, is the number of image features, For the The weight of the image features, For the The size of the image feature, is the number of geographic error features, For the The weight of the geographic error feature, is the size of the geographic error feature, is a preset constant.

[0030] In some embodiments of the present application, the updated and improved terrain model is visually displayed and marked, including:

[0031] The updated and improved terrain model is displayed through 3D visualization technology, and multiple elements on the terrain model are marked and annotated.

[0032] Correspondingly, the present application also provides a terrain surveying and mapping system based on aerial surveying and mapping technology, including:

[0033] The planning module is used to obtain the preliminary exploration information of the area to be measured, determine the basic information of the area to be measured and the regional control points within the area to be measured based on the preliminary exploration information of the area to be measured, obtain the aircraft information for implementing the aerial flight operation and the surveying and mapping requirements of the area to be measured, and plan the route of the first aerial photography based on the basic information of the area to be measured and the aircraft information;

[0034] A first aerial photography module is used to obtain meteorological data of the area to be measured, set flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be measured, aircraft information and meteorological data, and form a first aerial photography mission by integrating the route, flight information and photographic equipment information of the first aerial photography. Geographic image data of the area to be measured is collected through the first aerial photography mission, recorded as first geographic image data, and the first geographic image data is analyzed based on regional control points in the area to be measured to generate an initial terrain model of the area to be measured;

[0035] The second aerial photography module is used to divide the area to be tested according to geographical features through the initial terrain model to obtain multiple partial areas, evaluate the geographical image quality and terrain conversion accuracy in each partial area, thereby screening out unqualified partial areas, setting the route, flight information and photography equipment information of the second aerial photography for the unqualified partial areas, and combining the route, flight information and photography equipment information of the second aerial photography to form a second aerial photography task, and re-collecting geographical image data of the unqualified partial areas through the second aerial photography task, which is recorded as second geographical image data;

[0036] The optimization module is used to analyze the second geographic image data to update all unqualified partial areas, thereby updating and improving the initial terrain model of the area to be tested, and visually displaying and marking the updated and improved terrain model.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. Plan the route of the first aerial photography according to the basic information of the area to be measured and the aircraft information; set the flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be measured, the aircraft information and the meteorological data; set the flight and photographic conditions of the first aerial photography by comprehensively considering the route, surveying and mapping requirements, aircraft information and meteorological data to ensure the reliability of the first aerial photography and provide a reliable foundation for the subsequent second aerial photography.

[0039] 2. Analyze the first geographic image data based on the regional control points in the area to be measured to generate an initial terrain model of the area to be measured, and establish the initial terrain model in combination with the regional control points and the geographic image film to improve the stability of the initial surveying and mapping.

[0040] 3. Evaluate the geographic image quality and terrain conversion accuracy of each partial area, set the route, flight information and photography equipment information of the second aerial photography for the unqualified areas, so as to improve the effect of the second aerial photography and improve the quality of the data collected by the second aerial photography, so as to update and improve the terrain model of the area to be measured and improve the adaptability of terrain surveying and mapping. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 A schematic diagram of the flow of the terrain surveying and mapping method based on aerial surveying and mapping technology proposed by the present invention;

[0042] Figure 2 This is a schematic diagram of the structure of the terrain surveying and mapping system based on aerial surveying and mapping technology proposed in the present invention. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0044] Reference Figure 1 , a terrain surveying method based on aerial surveying technology. Aerial surveying technology is a means of mapping the positional relationship of ground objects using aircraft in the atmosphere as a measurement carrier. Its core purpose is to draw geodetic coordinates through data obtained from aerial photography, and then generate topographic maps and other related geographic information products. The following is a detailed explanation of aerial surveying technology:

[0045] Definition and Principle

[0046] Definition: Aerial surveying and mapping technology, also known as aerial surveying or aerial photogrammetry, is an important technology in the field of aeronautical engineering. It uses aerial photographic instruments carried by aircraft to continuously photograph the ground, and through subsequent data processing and analysis, it draws accurate topographic maps and other geographic information.

[0047] Principle: Aerial surveying and mapping technology is based on the principle of photogrammetry, which is to use photographic images to measure the size, shape and position of objects. In aerial surveying and mapping, the aircraft is used as a photographic platform to continuously shoot the ground, and obtain the three-dimensional coordinate information of the ground through geometric processing and analysis of the images.

[0048] This program includes the following steps:

[0049] Step S101, obtaining preliminary exploration information of the area to be measured, determining basic information of the area to be measured and regional control points in the area to be measured based on the preliminary exploration information of the area to be measured, obtaining aircraft information for implementing aerial flight operations and surveying and mapping requirements of the area to be measured, and planning the first aerial photography route based on the basic information of the area to be measured and the aircraft information.

[0050] In this embodiment, the basic information of the area to be measured includes range, shape, area, etc. The regional control points in the area to be measured are known and easily identifiable location points in the area, such as road intersections, mountain vertices, river confluences, etc. These control points will serve as the basis for subsequent terrain model accuracy verification and correction.

[0051] In some embodiments of the present application, the route of the first aerial photography is planned according to the basic information of the area to be measured and the aircraft information, including:

[0052] All routes are planned based on the basic information of the area to be measured and the aircraft information, and the flight information of the aircraft on each route is preliminarily determined. The basic information of the photographic equipment is obtained, and the shooting range and image overlap of the photographic equipment are determined based on the basic information of the photographic equipment and the preliminary range of the flight information. The optimal route is screened out from all routes based on the shooting range and image overlap of the photographic equipment, and the optimal route is used as the route for the first aerial photography.

[0053] In this embodiment, all possible routes are determined first, and then the preliminary range of the aircraft's flight information is preliminarily determined. The basic information of the photographic equipment includes the model, adjustable parameter range, and image overlap. In the fields of photogrammetry, remote sensing, or drone aerial photography, in order to obtain complete and continuous ground images and ensure that subsequent data processing (such as image stitching, three-dimensional reconstruction, etc.) can proceed smoothly, it is usually necessary to set a certain image overlap. According to the shooting range and overlap, you can start screening specific routes. The route should cover the area to be tested as much as possible, and ensure that there is enough overlapping area between adjacent routes (optimal route). Before the actual flight, the route can be simulated and verified. Through simulated flight, the rationality, safety, and efficiency of the route can be checked.

[0054] Step S102, obtaining meteorological data of the area to be measured, setting flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be measured, aircraft information and meteorological data, and combining the route, flight information and photographic equipment information of the first aerial photography to form a first aerial photography mission, collecting geographic image data of the area to be measured through the first aerial photography mission, recorded as first geographic image data, and generating an initial terrain model of the area to be measured based on the regional control points in the area to be measured by analyzing the first geographic image data.

[0055] In this embodiment, meteorological data includes wind speed, wind direction, light intensity, angle, temperature, etc., flight information includes flight altitude, speed, etc., and photographic equipment information includes resolution, focal length, viewing angle, etc. These factors are combined to determine the first aerial photography mission.

[0056] In some embodiments of the present application, the flight information and photographic equipment information of the first aerial photography are set according to the route of the first aerial photography, the surveying and mapping requirements of the area to be surveyed, the aircraft information and the meteorological data, including:

[0057] Matching the meteorological data with the route of the first aerial photography, determining the meteorological data at each position in the route of the first aerial photography, determining a first flight information range in the preliminary range of flight information in combination with the meteorological data and aircraft information, determining a second flight information range in the preliminary range of flight information according to the surveying and mapping requirements of the area to be surveyed, and setting the intersection of the first flight information range and the second flight information range as the flight information of the first aerial photography;

[0058] The photographic equipment information for the first aerial photography is determined based on the meteorological data, the surveying and mapping requirements of the area to be surveyed, and the flight information of the first aerial photography.

[0059] In this embodiment, the meteorological data is matched with the route of the first aerial photography, and the meteorological data at the corresponding time is predicted by the future time of the route of the first aerial photography. The first flight information range is determined in the preliminary range of the flight information by combining the meteorological data and the aircraft information. The conditions of safe flight under different meteorological conditions are different, so the first flight information range is determined. The second flight information range is determined in the preliminary range of the flight information according to the surveying and mapping requirements of the area to be measured. The flight conditions corresponding to different surveying and mapping requirements are different. For example, a flight altitude range and a flight speed are determined according to the surveying and mapping requirements, both of which will affect the aerial photography effect. Finally, the photographic equipment information of the first aerial photography is determined by comprehensively considering three factors, namely, the meteorological data, the surveying and mapping requirements of the area to be measured, and the flight information of the first aerial photography.

[0060] In some embodiments of the present application, the initial terrain model of the area to be measured is generated by analyzing the first geographic image data based on the regional control points in the area to be measured, including:

[0061] The first geographic image data is a plurality of images of the area to be measured arranged in a plurality of time sequences, each image of the area to be measured is preprocessed, a plurality of feature points are extracted from each image of the area to be measured, the feature points between adjacent images of the area to be measured are matched to form connection points, the plurality of images of the area to be measured are connected through the connection points, an importance index of each connection point is determined, the connection points are sorted according to the importance index, and a connection point sorting list is generated;

[0062] The area to be tested is divided into a plurality of sub-areas, and each sub-area is matched with a plurality of images of the area to be tested, and the control point density index of each sub-area is determined according to the regional control points in the area to be tested, and the number of encrypted point targets in each sub-area is determined by combining the control point density index and the image overlap between the plurality of images of the area to be tested, and some connection points are selected as encryption points in the connection point sorting list according to the number of encrypted point targets;

[0063] The image point coordinates of the regional control points in the area to be tested are identified in multiple images of the area to be tested, and the encrypted points are solved and the orientation elements of the images of the area to be tested are determined based on the image point coordinates of the regional control points and the actual coordinates, so as to help generate the initial terrain model of the area to be tested.

[0064] In this embodiment, the principle of aerial triangulation: aerial triangulation is a method of terrain mapping using aerial photographs. It measures the coordinates of the image points on the photograph and a small number of ground control point coordinates to calculate the exterior orientation elements of the photograph and the ground coordinates of the encryption points. According to the information of the aerial photographs and control points, a regional network model corresponding to the actual field is established, and the encryption points are selected on the model (photographic photographs). The selected encryption points are solved, and the plane coordinates and elevations are solved using the analytical aerial triangulation method. These solution results will be used for subsequent measurement and modeling work.

[0065] In this embodiment, the encrypted points are multiple points established by photogrammetry based on the image control points for internal control, model connection, orientation assistance, etc. These points are usually located in the survey area and are used to improve the accuracy and density of surveying and mapping. By arranging and solving the encrypted points, more and more accurate terrain information can be obtained, thereby improving the quality and practicality of surveying and mapping results. At the same time, the encrypted points can also be used for the construction and analysis of terrain models.

[0066] In this embodiment, in aerial photogrammetry, the orientation elements between the aircraft and the camera actually refer to the exterior orientation elements and interior orientation elements of the camera (installed on the aircraft) at the moment of photography. These elements together determine the position and attitude of the camera relative to the ground.

[0067] Determine method:

[0068] Determination of internal orientation elements: Internal orientation elements are usually completed through camera calibration. Camera calibration is a process of accurately measuring the internal parameters of the camera, including principal distance, image principal point coordinates, etc. These parameters are determined after the camera is manufactured and remain unchanged during subsequent use.

[0069] Determination of exterior orientation elements: The determination of exterior orientation elements is relatively complex and usually requires the use of ground control points (regional control points) and photogrammetry methods. Ground control points are points on the ground with known precise coordinates. By identifying these points on the photographic image and combining the known camera internal orientation elements and photogrammetry principles, the exterior orientation elements of the camera at the moment of photography can be solved. (A common method is to use collinearity equations. Collinearity equations describe the geometric relationship between ground points, photography centers, and image points. Through the known coordinates of ground control points and the coordinates of corresponding points on the image, a series of collinearity equations can be established, and the exterior orientation elements can be solved by mathematical methods).

[0070] In this embodiment, in order to select some points among the connection points as encryption points, each connection point is given an importance index (describing the contribution of the connection point to model building and mapping) and sorted by size.

[0071] In this embodiment, the control point density index is the number of control points per unit area. The control point density index and the image overlap between multiple images of the area to be measured (under the corresponding area) are combined to determine the number of encrypted point targets in each sub-area. Both the control point density index and the image overlap will affect the selection of the number of encrypted point targets, and the two together correspond to a target number. For example, when the number of regional control points is small and unevenly distributed (the control point density index is small), adding some encrypted points can effectively reduce the subsequent surveying and mapping coordinate conversion errors.

[0072] In some embodiments of the present application, the importance index of each connection point is determined, including:

[0073] The unmatched feature points between the images of the area to be tested are recorded as calibration points, the stability of each connection point is evaluated, the surrounding range of each connection point is mapped according to the stability, the number of calibration points and other connection points in the surrounding range are counted, and the importance index of the connection point is determined according to the number of calibration points and other connection points;

[0074] ;

[0075] in, is the importance index of the i-th connection point, is the conversion coefficient corresponding to the calibration point of the i-th connection point, is the number of calibration points around the i-th connection point, is the conversion coefficient of the other connection points of the ith connection point, is the number of other connection points within the vicinity of the i-th connection point.

[0076] In this embodiment, the stability of each connection point is evaluated and calculated by simulation software. The encrypted points should maintain a stable position and elevation under different time and environmental conditions. This means that they should be able to resist changes in position caused by natural factors (such as wind, rain, snow, etc.) or human factors (such as construction, vibration, etc.) to obtain stability. The higher the density of other points around the connection point, the greater the amount of information in the area, and the greater the role of the encrypted point may be. It is represented by the number of proofreading points and the number of other connection points.

[0077] Step S103, divide the area to be tested according to geographical features through the initial terrain model to obtain multiple partial areas, evaluate the geographic image quality and terrain conversion accuracy in each partial area, so as to screen out unqualified partial areas, set the route, flight information and photography equipment information of the second aerial photography for the unqualified partial areas, and combine the route, flight information and photography equipment information of the second aerial photography to form a second aerial photography task, and re-collect the geographic image data of the unqualified partial areas through the second aerial photography task, which is recorded as the second geographic image data.

[0078] In this embodiment, regions with the same or similar geographical features and adjacent locations are planned together to obtain multiple partial regions. The route, flight information and photography equipment information of the second aerial photography are set for the unqualified partial regions, and the relevant information of the second aerial photography is re-optimized and set considering the situation of the first aerial photography and the geographical image quality and terrain conversion accuracy of the unqualified regions.

[0079] In some embodiments of the present application, the area to be measured is divided into regions according to geographical features using an initial terrain model to obtain multiple partial regions, including:

[0080] Determine each geographic feature and position of the area to be tested based on the initial terrain model, integrate all geographic features, generate comprehensive geographic feature indicators (weighted summation or weighted average, etc.), divide the area to be tested into multiple small areas according to its size, and integrate adjacent small areas through comprehensive geographic feature indicators to obtain multiple partial areas.

[0081] In this embodiment, the spatial clustering or segmentation algorithm in the GIS software is used to assist the division.

[0082] In some embodiments of the present application, the geographic image quality and terrain conversion accuracy of each partial area are evaluated to screen out unqualified partial areas, including:

[0083] Determine the image features of each partial area, normalize the image features, evaluate the geographic error features of each partial area, determine the geographic image quality based on the image features, and determine the terrain conversion accuracy based on the geographic error features;

[0084] The screening index is generated by combining the geographic image quality and terrain conversion accuracy, and unqualified areas are screened out based on the screening index;

[0085] ;

[0086] in, is the screening index for the region, is the number of image features, For the The weight of the image features, For the The size of the image feature, is the number of geographic error features, For the The weight of the geographic error feature, is the size of the geographic error feature, is a preset constant.

[0087] In this embodiment, the image features include clarity, color restoration, and the degree of terrain detail retention, and the geographic error features include elevation error, position error, and other related conversion errors. Indicates the quality of geographic imagery, Indicates the terrain transformation accuracy, It represents the correction of the quality of geographic image by the accuracy of terrain transformation, thus obtaining the screening index.

[0088] Step S104, analyzing the second geographic image data to update all unqualified partial areas, thereby updating and improving the initial terrain model of the area to be tested, and visually displaying and marking the updated and improved terrain model.

[0089] In this embodiment, the second geographic image data is used to update the terrain model of the unqualified partial area, and the accuracy and authenticity of the terrain model are improved by re-performing stereo image pair matching, three-dimensional reconstruction and other steps.

[0090] In some embodiments of the present application, the updated and improved terrain model is visually displayed and marked, including:

[0091] The updated and improved terrain model is displayed through 3D visualization technology, and multiple elements on the terrain model are marked and annotated.

[0092] In this embodiment, the updated terrain model is checked and optimized as a whole to ensure the consistency and integrity of the model. The terrain model is further improved by filling gaps, smoothing edges, adjusting textures, and other methods. The updated and improved terrain model is rendered and displayed using three-dimensional visualization technology. By adjusting parameters such as viewing angle, lighting, and material, a realistic three-dimensional terrain effect is presented. This step helps to intuitively display terrain features and facilitate subsequent planning, design, analysis, and other work. Necessary marks and annotations are added to the terrain model, such as place names, roads, water bodies, buildings, and the like. These marks help users better understand the terrain model and facilitate its application.

[0093] Compared with the prior art, the present invention has the following beneficial effects:

[0094] 1. Plan the route of the first aerial photography according to the basic information of the area to be measured and the aircraft information; set the flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be measured, the aircraft information and the meteorological data; set the flight and photographic conditions of the first aerial photography by comprehensively considering the route, surveying and mapping requirements, aircraft information and meteorological data to ensure the reliability of the first aerial photography and provide a reliable foundation for the subsequent second aerial photography.

[0095] 2. Analyze the first geographic image data based on the regional control points in the area to be measured to generate an initial terrain model of the area to be measured, and establish the initial terrain model in combination with the regional control points and the geographic image film to improve the stability of the initial surveying and mapping.

[0096] 3. Evaluate the geographic image quality and terrain conversion accuracy of each partial area, set the route, flight information and photography equipment information of the second aerial photography for the unqualified areas, so as to improve the effect of the second aerial photography and improve the quality of the data collected by the second aerial photography, so as to update and improve the terrain model of the area to be measured and improve the adaptability of terrain surveying and mapping.

[0097] Through the description of the above implementation methods, those skilled in the art can clearly understand that the present invention can be implemented by hardware, or by software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present invention can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.), including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each implementation scenario of the present invention.

[0098] Correspondingly, the present application also provides a terrain mapping system based on aerial mapping technology, such as Figure 2 As shown, including,

[0099] The planning module is used to obtain the preliminary exploration information of the area to be measured, determine the basic information of the area to be measured and the regional control points within the area to be measured based on the preliminary exploration information of the area to be measured, obtain the aircraft information for implementing the aerial flight operation and the surveying and mapping requirements of the area to be measured, and plan the route of the first aerial photography based on the basic information of the area to be measured and the aircraft information;

[0100] A first aerial photography module is used to obtain meteorological data of the area to be measured, set flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be measured, aircraft information and meteorological data, and form a first aerial photography mission by integrating the route, flight information and photographic equipment information of the first aerial photography. Geographic image data of the area to be measured is collected through the first aerial photography mission, recorded as first geographic image data, and the first geographic image data is analyzed based on regional control points in the area to be measured to generate an initial terrain model of the area to be measured;

[0101] The second aerial photography module is used to divide the area to be tested according to geographical features through the initial terrain model to obtain multiple partial areas, evaluate the geographical image quality and terrain conversion accuracy in each partial area, thereby screening out unqualified partial areas, setting the route, flight information and photography equipment information of the second aerial photography for the unqualified partial areas, and combining the route, flight information and photography equipment information of the second aerial photography to form a second aerial photography task, and re-collecting geographical image data of the unqualified partial areas through the second aerial photography task, which is recorded as second geographical image data;

[0102] The optimization module is used to analyze the second geographic image data to update all unqualified partial areas, thereby updating and improving the initial terrain model of the area to be tested, and visually displaying and marking the updated and improved terrain model.

[0103] Those skilled in the art will appreciate that the accompanying drawings are merely schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily required for implementing the present invention.

[0104] Those skilled in the art will appreciate that the modules in the system in the implementation scenario can be distributed in the system of the implementation scenario according to the implementation scenario description, or can be changed accordingly and located in one or more systems different from the implementation scenario. The modules in the above implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0105] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A terrain surveying and mapping method based on aerial surveying and mapping technology, characterized in that: include, Obtain preliminary exploration information of the area to be measured, determine basic information of the area to be measured and regional control points within the area to be measured based on the preliminary exploration information of the area to be measured, obtain aircraft information for implementing aerial flight operations and surveying and mapping requirements of the area to be measured, and plan the first aerial photography route based on the basic information of the area to be measured and aircraft information; Acquire meteorological data of the area to be measured, set flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, surveying and mapping requirements of the area to be measured, aircraft information and meteorological data, form a first aerial photography mission by integrating the route, flight information and photographic equipment information of the first aerial photography, collect geographic image data of the area to be measured through the first aerial photography mission, record it as first geographic image data, and generate an initial terrain model of the area to be measured by analyzing the first geographic image data based on regional control points in the area to be measured; The area to be tested is divided into regions according to geographical features through the initial terrain model to obtain multiple partial regions, and the geographic image quality and terrain conversion accuracy in each partial region are evaluated, so as to screen out unqualified partial regions, and the route, flight information and photographic equipment information of the second aerial photography are set for the unqualified partial regions, and the route, flight information and photographic equipment information of the second aerial photography are integrated to form a second aerial photography mission, and the geographic image data of the unqualified partial regions are re-collected through the second aerial photography mission, which is recorded as the second geographic image data; Analyze the second geographic image data to update all unqualified partial areas, thereby updating and improving the initial terrain model of the area to be tested, and visually display and mark the updated and improved terrain model; in, Analyzing the first geographic image data based on the regional control points in the area to be measured to generate an initial terrain model of the area to be measured, including: The first geographic image data is a plurality of images of the area to be measured arranged in a plurality of time sequences, each image of the area to be measured is preprocessed, a plurality of feature points are extracted from each image of the area to be measured, the feature points between adjacent images of the area to be measured are matched to form connection points, the plurality of images of the area to be measured are connected through the connection points, an importance index of each connection point is determined, the connection points are sorted according to the importance index, and a connection point sorting list is generated; The area to be tested is divided into a plurality of sub-areas, and each sub-area is matched with a plurality of images of the area to be tested, and the control point density index of each sub-area is determined according to the regional control points in the area to be tested, and the number of encrypted point targets in each sub-area is determined by combining the control point density index and the image overlap between the plurality of images of the area to be tested, and some connection points are selected as encryption points in the connection point sorting list according to the number of encrypted point targets; Identify the image point coordinates of the regional control points in the area to be measured from multiple images of the area to be measured, and solve the encrypted points and determine the orientation elements of the images of the area to be measured according to the image point coordinates of the regional control points and the actual coordinates, so as to help generate the initial terrain model of the area to be measured; And determine the importance indicators of each connection point, including, The unmatched feature points between the images of the area to be tested are recorded as calibration points, the stability of each connection point is evaluated, the surrounding range of each connection point is mapped according to the stability, the number of calibration points and other connection points in the surrounding range are counted, and the importance index of the connection point is determined according to the number of calibration points and other connection points; ； in, is the importance index of the i-th connection point, is the conversion coefficient corresponding to the calibration point of the i-th connection point, is the number of calibration points around the i-th connection point, is the conversion coefficient of the other connection points of the ith connection point, is the number of other connection points within the vicinity of the i-th connection point; Evaluate the geographic image quality and terrain conversion accuracy of each partial area to screen out unqualified partial areas, including: Determine the image features of each partial area, normalize the image features, evaluate the geographic error features of each partial area, determine the geographic image quality based on the image features, and determine the terrain conversion accuracy based on the geographic error features; The screening index is generated by combining the geographic image quality and terrain conversion accuracy, and unqualified areas are screened out based on the screening index; ； in, is the screening index for the region, is the number of image features, For the The weight of the image features, For the The size of the image feature, is the number of geographic error features, For the The weight of the geographic error feature, is the size of the geographic error feature, is a preset constant.

2. The terrain surveying and mapping method based on aerial surveying and mapping technology according to claim 1, characterized in that: Plan the first aerial photography route based on the basic information of the area to be surveyed and the aircraft information, including: All routes are planned based on the basic information of the area to be measured and the aircraft information, and the flight information of the aircraft on each route is preliminarily determined. The basic information of the photographic equipment is obtained, and the shooting range and image overlap of the photographic equipment are determined based on the basic information of the photographic equipment and the preliminary range of the flight information. The optimal route is screened out from all routes based on the shooting range and image overlap of the photographic equipment, and the optimal route is used as the route for the first aerial photography.

3. The terrain surveying and mapping method based on aerial surveying and mapping technology according to claim 2 is characterized in that: The flight information and photography equipment information of the first aerial photography are set according to the route of the first aerial photography, the surveying and mapping requirements of the area to be surveyed, the aircraft information and the meteorological data, including: Matching the meteorological data with the route of the first aerial photography, determining the meteorological data at each position in the route of the first aerial photography, determining a first flight information range in the preliminary range of flight information in combination with the meteorological data and aircraft information, determining a second flight information range in the preliminary range of flight information according to the surveying and mapping requirements of the area to be surveyed, and setting the intersection of the first flight information range and the second flight information range as the flight information of the first aerial photography; The photographic equipment information for the first aerial photography is determined based on the meteorological data, the surveying and mapping requirements of the area to be surveyed, and the flight information of the first aerial photography.

4. The terrain surveying and mapping method based on aerial surveying and mapping technology according to claim 1, characterized in that: The initial terrain model is used to divide the area to be tested into regions according to geographical features, and multiple partial regions are obtained, including: Determine each geographic feature and position on the area to be tested based on the initial terrain model, integrate all geographic features to generate comprehensive geographic feature indicators, divide the area to be tested into multiple small areas according to its size, and integrate adjacent small areas through comprehensive geographic feature indicators to obtain multiple partial areas.

5. The terrain surveying and mapping method based on aerial surveying and mapping technology according to claim 1, characterized in that: The updated and improved terrain model will be visualized and marked, including: The updated and improved terrain model is displayed through 3D visualization technology, and multiple elements on the terrain model are marked and annotated.

6. A terrain surveying and mapping system based on aerial surveying and mapping technology, characterized in that: Used to implement the terrain surveying and mapping method based on aerial surveying and mapping technology as described in any one of claims 1 to 5, the system comprises: The planning module is used to obtain the preliminary exploration information of the area to be measured, determine the basic information of the area to be measured and the regional control points within the area to be measured based on the preliminary exploration information of the area to be measured, obtain the aircraft information for implementing the aerial flight operation and the surveying and mapping requirements of the area to be measured, and plan the route of the first aerial photography based on the basic information of the area to be measured and the aircraft information; A first aerial photography module is used to obtain meteorological data of the area to be measured, set flight information and photographic equipment information of the first aerial photography according to the route of the first aerial photography, the surveying and mapping requirements of the area to be measured, aircraft information and meteorological data, and form a first aerial photography mission by integrating the route, flight information and photographic equipment information of the first aerial photography. Geographic image data of the area to be measured is collected through the first aerial photography mission, recorded as first geographic image data, and the first geographic image data is analyzed based on regional control points in the area to be measured to generate an initial terrain model of the area to be measured; The second aerial photography module is used to divide the area to be tested according to geographical features through the initial terrain model to obtain multiple partial areas, evaluate the geographical image quality and terrain conversion accuracy in each partial area, thereby screening out unqualified partial areas, setting the route, flight information and photography equipment information of the second aerial photography for the unqualified partial areas, and combining the route, flight information and photography equipment information of the second aerial photography to form a second aerial photography task, and re-collecting geographical image data of the unqualified partial areas through the second aerial photography task, which is recorded as second geographical image data; The optimization module is used to analyze the second geographic image data to update all unqualified partial areas, thereby updating and improving the initial terrain model of the area to be tested, and visually displaying and marking the updated and improved terrain model.

Images