Recent advances in 3D scanning technologies allow us to acquire accurate and dense 3D scan data of large-scale environments efficiently.Currently,there are various methods for acquiring largescale 3D scan data,such as...Recent advances in 3D scanning technologies allow us to acquire accurate and dense 3D scan data of large-scale environments efficiently.Currently,there are various methods for acquiring largescale 3D scan data,such as Mobile Laser Scanning(MLS),Airborne Laser Scanning,Terrestrial Laser Scanning,photogrammetry and Structure from Motion(SfM).Especially,MLS is useful to acquire dense point clouds of road and road-side objects,and SfM is a powerful technique to reconstruct meshes with textures from a set of digital images.In this research,a registration method of point clouds from vehicle-based MLS(MLS point cloud),and textured meshes from the SfM of aerial photographs(SfM mesh),is proposed for creating high-quality surface models of urban areas by combining them.In general,SfM mesh has non-scale information;therefore,scale,position,and orientation of the SfM mesh are adjusted in the registration process.In our method,first,2D feature points are extracted from both SfM mesh and MLS point cloud.This process consists of ground-and building-plane extraction by region growing,random sample consensus and least square method,vertical edge extraction by detecting intersections between the planes,and feature point extraction by intersection tests between the ground plane and the edges.Then,the corresponding feature points between the MLS point cloud and the SfM mesh are searched efficiently,using similarity invariant features and hashing.Next,the coordinate transformation is applied to the SfM mesh so that the ground planes and corresponding feature points are adjusted.Finally,scaling Iterative Closest Point algorithm is applied for accurate registration.Experimental results for three data-sets show that our method is effective for the registration of SfM mesh and MLS point cloud of urban areas including buildings.展开更多
Semantic segmentation in the context of 3D point clouds for the railway environment holds a significant economic value,but its development is severely hindered by the lack of suitable and specific datasets.Additionall...Semantic segmentation in the context of 3D point clouds for the railway environment holds a significant economic value,but its development is severely hindered by the lack of suitable and specific datasets.Additionally,the models trained on existing urban road point cloud datasets demonstrate poor generalisation on railway data due to a large domain gap caused by non-overlapping special/rare categories,for example,rail track,track bed etc.To harness the potential of supervised learning methods in the domain of 3D railway semantic segmentation,we introduce RailPC,a new point cloud benchmark.RailPC provides a large-scale dataset with rich annotations for semantic segmentation in the railway environment.Notably,RailPC contains twice the number of annotated points compared to the largest available mobile laser scanning(MLS)point cloud dataset and is the first railway-specific 3D dataset for semantic segmentation.It covers a total of nearly 25 km railway in two different scenes(urban and mountain),with 3 billion points that are finely labelled as 16 most typical classes with respect to railway,and the data acquisition process is completed in China by MLS systems.Through extensive experimentation,we evaluate the performance of advanced scene understanding methods on the annotated dataset and present a synthetic analysis of semantic segmentation results.Based on our findings,we establish some critical challenges towards railway-scale point cloud semantic segmentation.The dataset is available at https://github.com/NNU-GISA/GISA-RailPC,and we will continuously update it based on community feedback.展开更多
基金This work was partially supported by JSPS KAKENHI[grant number 26420073].
文摘Recent advances in 3D scanning technologies allow us to acquire accurate and dense 3D scan data of large-scale environments efficiently.Currently,there are various methods for acquiring largescale 3D scan data,such as Mobile Laser Scanning(MLS),Airborne Laser Scanning,Terrestrial Laser Scanning,photogrammetry and Structure from Motion(SfM).Especially,MLS is useful to acquire dense point clouds of road and road-side objects,and SfM is a powerful technique to reconstruct meshes with textures from a set of digital images.In this research,a registration method of point clouds from vehicle-based MLS(MLS point cloud),and textured meshes from the SfM of aerial photographs(SfM mesh),is proposed for creating high-quality surface models of urban areas by combining them.In general,SfM mesh has non-scale information;therefore,scale,position,and orientation of the SfM mesh are adjusted in the registration process.In our method,first,2D feature points are extracted from both SfM mesh and MLS point cloud.This process consists of ground-and building-plane extraction by region growing,random sample consensus and least square method,vertical edge extraction by detecting intersections between the planes,and feature point extraction by intersection tests between the ground plane and the edges.Then,the corresponding feature points between the MLS point cloud and the SfM mesh are searched efficiently,using similarity invariant features and hashing.Next,the coordinate transformation is applied to the SfM mesh so that the ground planes and corresponding feature points are adjusted.Finally,scaling Iterative Closest Point algorithm is applied for accurate registration.Experimental results for three data-sets show that our method is effective for the registration of SfM mesh and MLS point cloud of urban areas including buildings.
基金Key Laboratory of Degraded and Unused Land Consolidation Engineering,Ministry of Natural Resources of China,Grant/Award Number:SXDJ2024-22Technology Innovation Centre for Integrated Applications in Remote Sensing and Navigation,Ministry of Natural Resources of China,Grant/Award Number:TICIARSN-2023-06+2 种基金National Natural Science Foundation of China,Grant/Award Numbers:42171446,62302246Zhejiang Provincial Natural Science Foundation of China,Grant/Award Number:LQ23F010008Science and Technology Program of Tianjin,China,Grant/Award Number:23ZGSSSS00010。
文摘Semantic segmentation in the context of 3D point clouds for the railway environment holds a significant economic value,but its development is severely hindered by the lack of suitable and specific datasets.Additionally,the models trained on existing urban road point cloud datasets demonstrate poor generalisation on railway data due to a large domain gap caused by non-overlapping special/rare categories,for example,rail track,track bed etc.To harness the potential of supervised learning methods in the domain of 3D railway semantic segmentation,we introduce RailPC,a new point cloud benchmark.RailPC provides a large-scale dataset with rich annotations for semantic segmentation in the railway environment.Notably,RailPC contains twice the number of annotated points compared to the largest available mobile laser scanning(MLS)point cloud dataset and is the first railway-specific 3D dataset for semantic segmentation.It covers a total of nearly 25 km railway in two different scenes(urban and mountain),with 3 billion points that are finely labelled as 16 most typical classes with respect to railway,and the data acquisition process is completed in China by MLS systems.Through extensive experimentation,we evaluate the performance of advanced scene understanding methods on the annotated dataset and present a synthetic analysis of semantic segmentation results.Based on our findings,we establish some critical challenges towards railway-scale point cloud semantic segmentation.The dataset is available at https://github.com/NNU-GISA/GISA-RailPC,and we will continuously update it based on community feedback.
