Laser Scanning in Heritage Documentation: The Scanning Pipeline and its Challenges

摘要

In an attempt to show the complexity of terrestrial laser scanning of heritage sites and dispel the not infrequently found perception of a largely automated tool with close to real time processing capabilities, the individual steps of the data acquisition and processing pipeline, including registration, point cloud cleaning, surface reconstruction, hole filling, texturing and final output are discussed. Emphasized are areas in which further development and research are desirable. A brief discussion of the concepts and implementation of the African Cultural Heritage Sites and Landscapes Project, as executed by the Zamani Research Group at the University of Cape Town, is incorporated into the paper. This database integrates spatial and non-spatial data and focuses on architectural heritage sites and cultural landscapes. The spatial data comprises of 3D laser scans, GIS's for each site and its environment, stereo images, panoramas, ground plans, elevations and sections derived from laser scan models,contextual photography and videos as well as 3D landscape models. The database is primarily designed as a resource for research and higher education. However, the spatial data acquired for the project are presently used in a number of restoration and conservation projects. An important further objective is the creation of a permanent digital record. The project, funded by the Andrew W. Mellon Foundation, is a joint initiative of the Zamani Research Group at the University of Cape Town and JStor, New York.