Real-world 3D model is a kind of digital representation of the real world, which can reflect the real form of real-world buildings, bridges, natural landforms and so on. Based on the acquired image data, video data and point cloud data, the process of modelling extracts the data feature points, complete the same name point matching, network construction, modeling mapping and other operations to generate realistic 3D model. The realistic 3D model can be achieved multi-source data fusion which is able to serve various industries as digital twin in base.

Digital Elevation Model (DEM) is a digital simulation of ground terrain in limited terrain elevation data. DEM can generate contour maps, perspective views, slope maps, cross-sections, and renderings by contour distance. It can also be used for spatial composites, surface analysis, and line analysis. Based on DEM, Digital Orthophoto Map (DOM) corrects the image elements of aerial photographs for their distortion. And all the corrected photographs are tiled inlay to an elevation model, which finally generated to the image result according to the coverage of image frame. DOM has both map geometric accuracy and image data characteristics.

Point cloud data represents much 3D structure information, which greatly compensates for the lack of spatial structure information of 2D pictures in many scenarios. The properties of point clouds include coordinates, normal vectors, color information and reflective surface insensitive of objects. Classified point cloud data according to pose, time and spatial topology can be used to  extract information about buildings, road surfaces, road boundaries, light poles, traffic signs, etc.