Documentation of weathered architectural heritage with visible, near infrared, thermal and laser scanning data

Abstract

[EN] Documentation of cultural heritage requires simple, quick and easy to use multi-sensor approaches to determine the state of conservation of monuments and sites. The documentation of a highly weathered architectural heritage such as the Obelisk Tomb is a good example to test the performance integrating multispectral imagery and laser scanning data. The Obelisk Tomb is the first important façade that a visitor sees while entering to the archaeological site of Petra in Jordan. The rich architectural formations carry Egyptian, Hellenistic and Nabataean influences. The damage that was inflicted on this unique monument led us to study it applying a number of modern digital techniques including 3D scanning, multispectral photography with visible and near infrared images, and thermography. All the multiband content is initially registered onto different multispectral bands. The multispectral information is enhanced and eventually draped onto the 3D laser scanning model in order to improve documentation and analysis of the state of conservation. Our results integrating the multispectral data, thermography and terrestrial laser scanning clearly enhance the power of diagnosis over the Obelisk Tomb with state-of-the-art optical equipment and image processing software. Furthermore, the capacity to examine, analyse and detect the existing damages is enhanced by the false colour processing of the input photographic data. Weathering effects are highlighted onto the 3D model and shed some light on the causes of the damages.