Digital Image Matching for Easy 3D Modelling

摘要

Digital image matching (DIM) did not arrive like a bolt from the blue. It has been around in the photogrammetric world for the past two decades but, through further improvements to filter approaches and also thanks to optimal adaption of algorithms for surface interpretation and object reconstruction, the technique has been refined to generate photo meshes out of 3D point clouds. Now, it is possible to produce 3D mesh models, point cloud data, digital surface models (DSMs) and true ortho images as data products by processing source data - primarily imagery and/or laser-scanned point clouds. The imagery can be obtained from aerial surveys, unmanned aerial vehicles (UAVs or 'drones'), as well as ground-based mobile and static image capture using a variety of camera types, ranging from GoPro through to purpose-built air survey camera systems. Bentley is a prominent market player with its ContextCapture application which is being embraced by a growing number of companies, including Topcon recently. GIM International asked John Taylor, who is responsible at Bentley Systems for reality modelling in Asia Pacific and in the global defence market, for a peek inside the 'black box'.