期刊名称:ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN:2194-9042
电子版ISSN:2194-9050
出版年度:2002
卷号:XXXIV Part 3 B
页码:138-141
出版社:Copernicus Publications
摘要:The 30 m high cylindrical monument "Dhamek Stupa" is located at Sarnath in India. The Stupa was build about 2200 years ago in the district of Uttar Pradesh, where Buddha is said to have preached his First Sermon. On October 11-13 th 2002 the famous Buddhist ritual "Kalachakra" will take place at Graz. On the occasion of this event the idea of building a virtual 3D-model of the Stupa using modern photogrammetric and computer vision methods was born. While on expedition in India in 1982, R. Kostka took photographs of the Stupa with a non-calibrated Hasselblad camera. Two images have been taken in approximated canonical stereo configuration, a third photo in a convergent direction (from the same position). Besides the nominal focal length (100mm), only the length of the baseline and some approximate dimensions of the Stupa are known. In order to reconstruct the Stupa's surface the stereo images have been oriented on a digital photogrammetric station (DPS). Point measurements – taken either manually or by digital point transfer – were subsequently used for self-calibration of the camera (focal length only). Once all of the Stupa's parts had been mod- elled geometrically using different methods (geometric primitives, point and edge measurements), the surface patches were triangu- lated manually or by delaunay triangulation. The non visible parts on the backside have been modelled by cylindrical and conical patches, which are continued symmetrically from the front. The different parts – which had been stored using the GNU Triangulated Surface (GTS) format - have been converted into the VRML 2.0 format and assembled into a single scene for viewing with any stan- dard VRML viewer.