An Automatic Texture Mapping Method Of 3D Building Models Based On Oblique Photogrammetry

Oriented toward demand in development from Digital City to Smart City,multi levels of detail 3D city reconstruction had been a research focus.Existing oblique photogrammetry scheme can produce large scale of triangular terrain model with rich texture information automatically.However,the produced triangle mesh model does not have complete topological and semantic information.To support the application of complex scenes such as Smart City,it is necessary to introduce single independent 3D building model with complete topological and semantic information.The texture mapping of 3D building model often had occlusion,distortion and fuzzy problems causing by the mutual occlusions of buildings and fusion of multi view images,made it a hot and difficult research spot in detailed 3D building model reconstruction field.Aiming at the problems of 3D building model's texture mapping algorithm,this paper presented an automatic 3D building model texture mapping method.It is based on the triangle mesh model with rich texture information produced by oblique photogrammetry scheme,by introducing render to texture technique,render the textures of triangle mesh model to the surface of building model directly.The main researches within this paper including:1.Introducing the research background and meaning of this paper,summarize the existing researches status and defects of 3D building models' texture mapping methods at home and abroad.Meanwhile proposed the research purpose and content of this paper.2.Correspond triangle mesh model and single independent 3D building model.Based on the spatial characters of single independent 3D building model,dividing and recombine face cells as clusters,extract render primitives,to simplify following procedures and reduce time complexity of proposed method.3.Based on the spatial information of render primitives,introducing render to texture method and computer vision tools such as view frustum and frame buffer object to obtain textures of triangle mesh model,realize the texture extraction of oblique photogrammetry scheme produced triangle mesh model.4.Based on max rectangle bin packing method,packing obtained discrete rectangular textures into single texture atlas and remapping it to the surface of 3D building model,compress the space occupancy and decrease the amount of textures,subsequently optimize rendering efficiency of models.To verify the effectiveness and validity of proposed method,the proposed method was experimented based on oblique photogrammetry data of an area collecting by SWDC-5 sensors.Triangle mesh model and single independent model were build for a target building,subsequently textures were extracted and mapped by proposed method and image-based method separately.The experimental results shown that the proposed method can effectively solve the occlusion,distortion and color aberration problems rather than normal texture mapping method for 3D building models,and having more accurate texture mapping quality.