March 22, 2024 Video/Audio Open Access

Non-invasive, virtual unpacking of enclosed cuneiform - 3D reconstruction and visualization of clay tablets based on data acquired by portable micro-CT scanner

Olbrich, Stephan

In this video animation we visualize the reconstruction of an enclosed cuneiform tablet (Louvre Museum, collection no. AO8295, 19th century BC, showing a loan contract, 5.9 cm x 6.1 cm x 2.1 cm) and the envelope. The surface reconstruction, feature analysis, segmentation, and visualization was performed by "EXAVIS42" - which was developed by the author, as part of the project - from high-resolution volume data (38 µm voxel size), acquired by the portable micro-CT scanner "ENCI" - constructed as part of the project - at the collection of the Louvre Museum (Paris). The cuneiform signs are emphasized by a diffuse lighting model, combined with curvature-oriented highlighting and darkening, and shadowing by precalculated ambient occlusion, implementing an optimized function for weighting orientations of rays and their distances of crossed surfaces. The video clip was exported from "EXAVIS42" as a sequence of 4.850 anti-aliased images in 1920x1080 resolution (50 frames per second), off-screen rendered in OpenGL, by taking advantage of key frame animation, interpolating camera positions and orientations, as well as numerous visualization parameters.