Documentation of Weathered Architectural Heritage with Visible, Near Infrared, Thermal and Laser Scanning Data

Article · June 2012with 43 Reads 
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Abstract
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.

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  • Chapter
    Many human, technical, and economic resources are devoted nowadays to document cultural heritage. Nevertheless, the resources are limited and heritage in general is suffering not only from anthropogenic and natural disasters but also from varying physical and chemical conditions. This paper summarizes a wide range of recording and documentation activities carried out at the Petra Archaeological Park, in particular, at Djinn Block No. 9 to improve the level of understanding of that iconic monument. The recording and documentation considered a wide range of metric and multispectral techniques such as close-range photogrammetry, terrestrial laser scanning, multispectral photography, thermography, and remote sensing to build up scientific knowledge of the monument prior to undertaking conservation and preservation measures. The conventional 3D documentation with visible colors was accompanied by layers of multispectral information that were used to inspect and monitor the deterioration of the monument, as a step to take the right conservation and preservation initiatives. Besides the scientific documentation and conservation, dissemination is considered as a vital part of any survey to raise awareness to the society (both local and foreigners, even visitors) about its wellness (even if it is very much deteriorated). The dissemination is implemented for mobile devices (apps for mobile phones and tablets) to integrate different layers of information: 3D, history, multispectral imagery, geo-localization, geo-services, and last but not least cyber-archaeology to visualize fully textured ideal 3D reconstructions of the past periods on multiple platforms. A critical view of the different steps ranging from data acquisition, processing (geometry and spectral content), and post-processing to deliver cyber-archaeological products will be analyzed.
  • Article
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  • Article
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