ENGINEERING

A new virtual reality system for scanning and exhibiting museum artefacts has been developed that promises to faithfully reproduce surface texture and shine. The system developed by the IST-funded ViHAP3D project presents cultural artefacts using high resolution 3D virtual reality graphics. "We developed the procedure for capturing 3D models with their reflective properties, through a system that combines the object's geometry, appearance and glossiness," says Christel Weins of the Max-Planck Institut für Informatik and ViHAP3D coordinator. "We obtain data in the photographic studio, where we illuminate the facets of the object from different angles and so determine the reflection characteristics of every point of the surface." The project has developed post-processing systems for representing and rendering the 3D objects, and this work has lead to the publication of over twenty scientific papers. Work has also been undertaken on displaying the artefacts. "The ViHAP3D partners from Spain developed a virtual museum builder and browser that enables you to take these digital artefacts from the database and create your own museum,” adds Weins. An attractive feature is that the digital replicas can be viewed on high-speed workstations or humble laptops. The system supports the use of virtual reality applications and projection screens, with which stereoscopic images can be viewed. The images for ordinary laptops and workstations are prepared in advance by the ViHAP3D system so that only processed images need to be displayed. The process involved taking a computerised wire-frame geometry, simplifying some of the detail to limit the amount of computational effort required, to which the reflectance characteristics of the object are then applied. “We've carried out extensive user requirements analysis and evaluations, especially with museums and experts, and the feedback has been very positive," says Weins. For example, a virtual kiosk has been set up the museum at Pisa, where various user studies have been carried out that show a high level of acceptance of the system. As for commercial exploitation of the system, it is perhaps 'early days'. "The 3D browser is stable and useable, and we have the algorithm for digitising 3D objects," says Weins. "At the moment, however, the algorithm is not very useable for non-experts and training is needed to carry out the process. There is currently no commercial solution that can adequately handle the huge datasets that the digitising process produces. Perhaps there's scope here for a further project involving research institutes, commercial concerns and industrial partners."