A photogrammetry information three-dimensional visualization method based on grid real-time non-uniform division

Abstract

The application provides a photogrammetry information three-dimensional visualization method based on grid real-time non-uniform division, which is used for realizing high-precision three-dimensional ground information acquisition and visualization presentation, and relates to the intersection field of photogrammetry technology field and computer graphics processing technology field. First, high-precision photogrammetry information data of a region to be measured is acquired, photogrammetry data is analyzed and processed in combination with a grid real-time non-uniform division technology, and accurate measurement and identification of three-dimensional information such as ground topography, buildings and vegetation are realized. Meanwhile, the application also provides a front-end visualization method, which presents measurement results in an intuitive and interactive manner, so that users can quickly acquire, analyze and apply ground information. The application has high use value in aspects such as geological disaster emergency rescue, geological disaster reconstruction, real-time ground detection and fine measurement.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary field of photogrammetry and computer graphics processing, and specifically relates to a three-dimensional visualization method for photogrammetric information based on real-time non-uniform grid division. Background Technology

[0002] With the development of computer vision and graphics processing technologies, photogrammetry is advancing towards higher precision and real-time performance. The demand for 3D visualization of photogrammetric information is increasing in fields such as terrain modeling, urban planning, and disaster management. Traditional surface gridding methods typically divide the surface area into fixed-size regions for measurement and analysis. While this method is simple and easy to implement, for complex terrain features and uneven distribution of surface information density, uniform gridding not only increases computational load and reduces visualization efficiency and accuracy, but also fails to dynamically adjust the grid size to adapt to terrain variations and surface contours. Furthermore, the discrete units used to represent map information after surface gridding may not accurately reflect terrain details and continuity. Therefore, this uniform gridding method may not be suitable for complex terrain and deformation, resulting in low measurement accuracy. To address this issue, a real-time non-uniform gridding technique can be used. This technique employs an adaptive gridding method that dynamically adjusts the grid size and shape based on surface features and deformation, resulting in more refined and accurate gridding of the measurement area.

[0003] With the development of geographic information technology, the use of front-end 3D visualization methods to display surface data is becoming increasingly popular. 3D visualization methods present measurement results to users in an intuitive and interactive way, facilitating data analysis and application. In 3D surface information identification, 3D visualization methods can display measurement results in the form of 3D models, images, etc., allowing users to browse and analyze data from multiple angles and scales through an interactive interface. 3D visualization methods can improve users' understanding and application of surface information, promoting decision-making and implementation. Therefore, managing multi-source heterogeneous observation data and realizing functions such as 3D visualization of surface deformation information, deformation trend analysis, query statistics, dynamic management, deformation information chart output, and result analysis, thereby enhancing capabilities in geological disaster emergency response, geological disaster reconstruction, real-time surface detection, and refined measurement, is of great significance for constructing a 3D scene visualization intelligent information platform.

[0004] Based on this, a three-dimensional visualization method for photogrammetric information based on real-time non-uniform grid division is proposed to solve the above problems. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a three-dimensional visualization method for photogrammetric information based on real-time non-uniform grid division.

[0006] To achieve the above-mentioned invention and other related objectives, the present invention provides a three-dimensional visualization method for photogrammetric information based on real-time non-uniform grid division. The method includes the following modules: a photogrammetric module, a real-time non-uniform grid division module, a data processing module, a front-end visualization module, and a result output module.

[0007] A. Photogrammetry module

[0008] The photogrammetry module can receive and process data from multiple sources, and perform processing and analysis to extract surface topographic information. Utilizing image processing, data preprocessing, and other techniques, it can acquire high-precision topographic information, providing a data foundation for subsequent surface information analysis and visualization.

[0009] B. Real-time Non-uniform Mesh Generation Module

[0010] A real-time non-uniform grid partitioning technique is employed to adaptively divide terrain information into grids, dynamically adjusting the grid size and shape based on surface features and deformation. During grid partitioning, the real-time non-uniform grid partitioning module first determines the grid extent of the entire measurement area based on the coverage and resolution of the photogrammetric data. Then, the entire area is divided into a series of smaller grids, each used for local terrain information extraction. The size and shape of each grid can be adjusted according to surface features; for example, in areas with complex terrain, the grid size can be reduced to improve the accuracy of terrain information, while in flat areas, the grid size can be appropriately increased to reduce information extraction and processing time.

[0011] C. Data Processing Module

[0012] The data processing module extracts and calculates terrain information by processing and analyzing photogrammetric data. It utilizes image processing, computer vision, and geographic information systems technologies, combined with diverse data sources such as UAVs, remote sensing data, and satellite data, to acquire high-precision terrain information, providing a data foundation for subsequent surface information analysis and visualization.

[0013] D. Front-end visualization module

[0014] Through the front-end visualization module, users can intuitively observe and analyze the extracted terrain information, understanding the undulations and changes of the land surface. Through interactive operations, users can freely select and adjust display parameters, achieving multi-angle, multi-scale terrain visualization. This intuitive and interactive visualization method helps users better understand terrain information, providing support for applications in fields such as geographic surveying, geomorphological analysis, and urban planning.

[0015] E. Results Output Module

[0016] Users can output processed and visualized terrain information in various formats to meet the needs of different application scenarios. This facilitates the use of results in fields such as geographic surveying, geomorphological analysis, and urban planning, and allows for data exchange and sharing with other software and systems. Outputting measurement results as images or other formats allows users to perform further analysis and applications.

[0017] The present invention adopts the following technical solution:

[0018] A method for 3D visualization of photogrammetric information based on real-time non-uniform grid division, the method comprising the following steps:

[0019] (1) Obtain measurement data of the identification area using multivariate photographic data:

[0020] By leveraging diverse data sources such as drones, synthetic aperture radar (SAR), digital elevation models (DEM), and satellite data, multidimensional imagery of the target area is acquired. Throughout the data collection process, the drones fly along pre-set routes and camera parameters to capture continuous aerial images. Through technologies such as SAR and DEM, surface information, color images, and point cloud data can be obtained, ultimately enabling 3D terrain reconstruction and the creation of continuous frame image sequences from video data.

[0021] (2) Establish a comprehensive database for photogrammetric data and information analysis:

[0022] The basic surface information and photogrammetric data from step (1) are stored in a database for management. Photogrammetric data can be categorized and labeled according to different attributes, time, geographical location, etc., facilitating retrieval and access. It can also serve as a centralized data storage platform, enabling data sharing and collaboration among multiple users. Different users can access and obtain aerial data through the database for various analyses and applications.

[0023] (3) Use real-time non-uniform grid division technology to divide the land surface:

[0024] The data from step (2) is exported to the real-time non-uniform grid partitioning module. This technology dynamically generates highly adaptable grid partitioning based on the undulations and changes in different terrain features, ensuring that the size and shape of the grid can adapt to the surface undulations and changes to the greatest extent possible. To further improve the accuracy and precision of the grid, real-time non-uniform grid partitioning allows users to manually refine specific grid areas. Users can manually refine the grid in areas requiring finer grid partitioning through the interactive interface to obtain higher resolution terrain data.

[0025] (4) Three-dimensional visualization of photogrammetric information data of the study area:

[0026] The basic data and grid-processed surface data in steps (2) and (3) are used to obtain accurate coordinates and orientation information of the 3D surface model using techniques such as image matching and geographic coordinate transformation. Three.js technology is chosen to visualize the 3D surface model and other geographic data on the front end. A high-performance interactive 3D and 2D graphics are rendered in a web browser using a visualization platform and JavaScript API technology, allowing users to control the viewpoint, zoom in and out, measure distances and areas, etc., via mouse or touch. This allows users to interact with the data and obtain more geographic information, thus achieving the visualization of geographic data.

[0027] (5) Editing, modifying, storing, and exporting surface identification information from photogrammetric data:

[0028] Based on the 3D surface model obtained in step (4), users can use the feature identification information on the front-end visualization platform to edit and modify it. This can be done by adding markers, drawing areas or lines on the features. This functionality can be achieved using front-end development technologies such as JavaScript, HTML, and CSS. To enable secondary modification and export, the modified information can be transferred to a storage array in the database, allowing for simultaneous modification and saving of information in the database. The front-end visualization platform also provides the function of exporting the edited and modified feature identification information. Users can choose the data format and file type for export, such as CSV, GeoJSON, KML, etc.

[0029] The present invention has the following advantages:

[0030] (1) Photogrammetric data can be used to generate a three-dimensional point cloud of the land surface by registering and feature matching multi-source data images such as UAVs, synthetic aperture radar, digital elevation models, and satellite data. A three-dimensional point cloud is a land surface model composed of a large number of discrete points, and the coordinates of each point represent the location of the point in geographic space. Through the three-dimensional point cloud, terrain information such as elevation, slope, and topographic relief can be obtained in real time.

[0031] (2) Traditional grid division methods typically divide the surface area into regions of fixed size for measurement and analysis. In contrast, the real-time non-uniform grid division module in this invention adopts an adaptive grid division strategy, which can dynamically adjust the grid size and shape according to surface features and deformation. This adaptive grid division method can better adapt to complex landforms and deformation conditions, improving the accuracy and precision of terrain information.

[0032] (3) The front-end visualization module in this invention supports interactive operation, allowing users to freely select and adjust display parameters to achieve multi-angle and multi-scale terrain visualization. This interactive visualization method can help users better understand terrain information and perform terrain analysis and applications. Attached Figure Description

[0033] Figure 1 This is a flowchart illustrating the implementation of a three-dimensional visualization method for photogrammetric information based on real-time non-uniform grid partitioning, as described in this invention. Figure 2 These are the specific steps of the real-time non-uniform grid partitioning technique in this invention. Detailed Implementation

[0034] The workflow of the present invention will be further described below with reference to the accompanying drawings:

[0035] A method for 3D visualization of photogrammetric information based on real-time non-uniform grid partitioning mainly includes: acquisition and standardization of photogrammetric image data of the study area; establishment of a comprehensive database for photogrammetric data and information analysis; delineation of the land surface using real-time non-uniform grid partitioning technology; front-end 3D visualization of photogrammetric data of the area to be studied; and editing, modification, storage, and export of land surface identification information from the photogrammetric data. The specific steps are as follows:

[0036] (1) Collect surface images of the target area using multivariate photogrammetric data. The surface images should cover all angles and areas of the target area to obtain comprehensive topographic information, and then import it into a comprehensive database.

[0037] (2) On the front-end page, by selecting the area of ​​the surface study, the collected surface images are preprocessed to obtain the coordinate set attribute data of the area, and a table is created in the database to store the aerial photography information. SQL statements or corresponding database operation methods are used to insert the parsed surface aerial photography information into the database table. And Ajax technology is used to interact with the database.

[0038] (3) Using a real-time non-uniform grid partitioning algorithm, a grid partitioning method is dynamically generated based on aerial images and surface features to adapt to terrain features and deformation. This grid partitioning method ensures that the size and shape of the grid can adapt to the undulations and changes of the surface to the greatest extent.

[0039] (4) In the front-end visualization drawing page of the surface identification information of the measurement data, the HTML is used to... The element creates multiple tables to display the surface information in the database, and enters the data into the table header, table footer, coordinate points and surface identification information respectively to construct a three-dimensional surface information model.

[0040] (5) Implement the page structure, style settings, interactive logic, and dynamic effects of the web page using HTML, CSS, and JavaScript programming languages. Select any coordinate point from the drawn 3D surface information model, obtain the basic geographic number of the surface by picking the attribute data of the coordinate set within the area, and use DOM manipulation to perform operations such as adding, deleting, modifying, and querying elements. Use Ajax methods to communicate asynchronously with the server and interact with the information analysis database to achieve a rich and diverse user interaction experience.

[0041] (6) Place the generated surface identification information cloud map and the cumulative deformation of individual coordinate points from the measured data onto the front-end visualization platform. Elements and Within the table element, JavaScript listens for the table's edit events via the `input` command, modifies the table's content, and saves it in the corresponding data structure or variable. Ajax technology is then used to send the data to the server, enabling information editing and modification. During file export, the edited and modified data is converted to the required file format, such as CSV, GeoJSON, or KML. After generating the file, it is either saved to the server or a download link is created, thus implementing the file export function.

Claims

1. A method for three-dimensional visualization of photogrammetric information based on real-time non-uniform grid division, belonging to the interdisciplinary field of photogrammetry and computer graphics processing, characterized in that... include: This system acquires high-precision 3D photogrammetric information of the area to be measured, including 3D information such as terrain and buildings. Simultaneously, it combines a real-time non-uniform grid generation module and a data processing module to generate a non-uniform grid in real time based on surface information density and user requirements. By analyzing the information density in the photogrammetric data, the system performs non-uniform grid generation on the area to be measured. The grid size and shape are dynamically adjusted according to surface features and deformation. Based on the actual surface conditions, the grid density is increased in areas with obvious surface features, making the grid denser in information-intensive areas, and decreased in areas with less obvious surface features, making the grid sparser in information-sparse areas. This allows for the accurate and rapid acquisition of terrain parameters such as terrain height, slope, and undulation, constructing a 3D surface information model.

2. After processing photogrammetric information based on real-time non-uniform grid division as described in claim 1, interactive operation through a front-end visualization module can help users better understand terrain information and interact with the 3D model using devices such as a mouse or touchscreen. For example, users can drag, rotate, and zoom the terrain model to change the viewpoint and observe different parts of the terrain. Users can also perform terrain profile analysis, measure distances and areas, etc., to obtain more detailed terrain information. Simultaneously, the measurement results can be output as images or other formats for further analysis and application. Users can save the visualization results as image files or export them as 3D model data for use by other software and systems.

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