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Item Geometry and Attribute Compression for Voxel Scenes(The Eurographics Association and John Wiley & Sons Ltd., 2016) Dado, Bas; Kol, Timothy R.; Bauszat, Pablo; Thiery, Jean-Marc; Eisemann, Elmar; Joaquim Jorge and Ming LinVoxel-based approaches are today's standard to encode volume data. Recently, directed acyclic graphs (DAGs) were successfully used for compressing sparse voxel scenes as well, but they are restricted to a single bit of (geometry) information per voxel. We present a method to compress arbitrary data, such as colors, normals, or reflectance information. By decoupling geometry and voxel data via a novel mapping scheme, we are able to apply the DAG principle to encode the topology, while using a palette-based compression for the voxel attributes, leading to a drastic memory reduction. Our method outperforms existing state-of-the-art techniques and is well-suited for GPU architectures. We achieve real-time performance on commodity hardware for colored scenes with up to 17 hierarchical levels (a 128K3 voxel resolution), which are stored fully in core.Item Compressed Multiresolution Hierarchies for High-Quality Precomputed Shadows(The Eurographics Association and John Wiley & Sons Ltd., 2016) Scandolo, Leonardo; Bauszat, Pablo; Eisemann, Elmar; Joaquim Jorge and Ming LinThe quality of shadow mapping is traditionally limited by texture resolution. We present a novel lossless compression scheme for high-resolution shadow maps based on precomputed multiresolution hierarchies. Traditional multiresolution trees can compactly represent homogeneous regions of shadow maps at coarser levels, but require many nodes for fine details. By conservatively adapting the depth map, we can significantly reduce the tree complexity. Our proposed method offers high compression rates, avoids quantization errors, exploits coherency along all data dimensions, and is well-suited for GPU architectures. Our approach can be applied for coherent shadow maps as well, enabling several applications, including high-quality soft shadows and dynamic lights moving on fixed-trajectories.Item The Online Anatomical Human: Web-based Anatomy Education(The Eurographics Association, 2016) Smit, Noeska; Hofstede, Cees-Willem; Kraima, Annelot; Jansma, Daniel; deRuiter, Marco; Eisemann, Elmar; Vilanova, Anna; Beatriz Sousa Santos and Jean-Michel DischlerThe Online Anatomical Human (OAH) is a web-based viewer for studying anatomy. It is based on real human anatomy and incorporates medical image data in linked 2D and 3D views that students can freely interact with. Our application is the only to support 2D and 3D views based on real medical imaging data. The main goal of this anatomical online resource is to serve as an educational platform available to anyone with access to a modern web browser. Users can annotate regions, add comments, and provide hyperlinks to additional media. By making our work accessible to medical experts, we can ensure an increasing amount of information, leading to an evergrowing gain in educational value. The OAH will be used in an upcoming Massive Open Online Course (MOOC) to teach anatomy of the pelvis and will be made available to students worldwide via the web.