Research Activities

Over the last decade Visual Computing has established itself as a core discipline within computer science and information technology. Its research scope covers the design of computational and mathematical methods and interactive systems for geometric and physics-based modeling, image acquisition and synthesis, scientic visualization, as well as virtual reality. As a result, visual computing research is providing enabling technology for a broad spectrum of applications in all of CRS4 thematic areas. The Visual Computing Group has been founded in 1996, and has gradually become one of the leading Italian research programs in the domain.

Research activities span many areas of computer graphics and computer vision, the primary focus being the study and development of scalable technology for acquiring, creating, distributing and exploring massive models, as well as for integrating them in real-time interactive visual simulations and virtual environments, both in local and distributed settings.

Current projects range from desktop 3D tools to immersive virtual environments with haptic feedback. Representative examples of our research domains are the following:

Effective acquisition of color and shape of 3D models. We focus on techniques for effectively combining acquired colorimetric and geometric information using multiple sensors. In particular, we proposed advanced techniques for mapping photographic datasets to dens 3D models acquired with laser scanning, for acquiring 3D models in highly cluttered environments, and for capturing indoor scenes.
Representative publications
  1. Ruggero Pintus and Enrico Gobbetti. A Fast and Robust Framework for Semi-Automatic and Automatic Registration of Photographs to 3D Geometry. ACM Journal on Computing and Cultural Heritage, 7(4): 23:1-23:23, February 2015. https://doi.org/10.1145/2629514.

  2. Fabio Bettio, Alberto Jaspe Villanueva, Emilio Merella, Fabio Marton, Enrico Gobbetti, and Ruggero Pintus. Mont'e Scan: Effective Shape and Color Digitization of Cluttered 3D Artworks. ACM Journal on Computing and Cultural Heritage, 8(1): 4:1-4:23, 2015. https://doi.org/10.1145/2644823.

  3. Claudio Mura, Oliver Mattausch, Alberto Jaspe Villanueva, Enrico Gobbetti, and Renato Pajarola. Automatic Room Detection and Reconstruction in Cluttered Indoor Environments with Complex Room Layouts. Computers & Graphics, 44: 20-32, November 2014. https://doi.org/10.1016/j.cag.2014.07.005.

Rendering and streaming of terrains and urban environments. We develop multi-resolution out-of-core techniques for rapid high-quality distribution and visualization of textured digital terrain models and high resolution urban environments.
Representative publications
  1. Paolo Cignoni, Marco Di Benedetto, Fabio Ganovelli, Enrico Gobbetti, Fabio Marton, and Roberto Scopigno. Ray-Casted BlockMaps for Large Urban Models Visualization. Computer Graphics Forum, 26(3): 405-413, September 2007. Proc. Eurographics 2007.

  2. Enrico Gobbetti, Fabio Marton, Paolo Cignoni, Marco Di Benedetto, and Fabio Ganovelli. C-BDAM - Compressed Batched Dynamic Adaptive Meshes for Terrain Rendering. Computer Graphics Forum, 25(3): 333-342, September 2006. Proc. Eurographics 2006.

  3. Paolo Cignoni, Fabio Ganovelli, Enrico Gobbetti, Fabio Marton, Federico Ponchio, and Roberto Scopigno. BDAM - Batched Dynamic Adaptive Meshes for High Performance Terrain Visualization. Computer Graphics Forum, 22(3): 505-514, September 2003. Proc. Eurographics 2003 - Second Best Paper Award.

Processing, distribution, and rendering of massive dense 3D meshes and point clouds. We look at techniques for supporting inspection of surface models characterized by a high sample density, such as those generated by laser scanning. One of our results is the introduction of a coarse grained multiresolution model based on hierarchical volumetric decomposition, that lead to the first GPU bound high quality techniques for large scale meshes and point clouds.
Representative publications
  1. Paolo Cignoni, Fabio Ganovelli, Enrico Gobbetti, Fabio Marton, Federico Ponchio, and Roberto Scopigno. Batched Multi Triangulation. In Proceedings IEEE Visualization. Pages 207-214. IEEE Computer Society Press, October 2005.

  2. Enrico Gobbetti and Fabio Marton. Layered Point Clouds - a Simple and Efficient Multiresolution Structure for Distributing and Rendering Gigantic Point-Sampled Models. Computers & Graphics, 28(6): 815-826, December 2004.

  3. Paolo Cignoni, Fabio Ganovelli, Enrico Gobbetti, Fabio Marton, Federico Ponchio, and Roberto Scopigno. Adaptive TetraPuzzles - Efficient Out-of-core Construction and Visualization of Gigantic Polygonal Models. ACM Transactions on Graphics, 23(3): 796-803, August 2004. Proc. SIGGRAPH 2004.

Processing, distribution, and rendering of huge complex 3D models. We focus on methods able to support very large arbitrary surface models with high topological genus, highly variable depth complexity, fine geometric detail, and non-conforming tessellations. Models of this kind arise from numerical simulation and computer aided design. One of our results is the introduction of volumetric methods based on multi-scale modeling of appearance rather than geometry with tight integration of visibility and LOD construction, that lead to the first solution for exploring massive CAD models and simulation results on commodity PCs.
Representative publications
  1. Marco Di Benedetto, Fabio Ganovelli, Marcos Balsa Rodriguez, Alberto Jaspe Villanueva, Roberto Scopigno, and Enrico Gobbetti. ExploreMaps: Efficient Construction and Ubiquitous Exploration of Panoramic View Graphs of Complex 3D Environments. Computer Graphics Forum, 33(2): 459-468, 2014. https://doi.org/10.1111/cgf.12334. Proc. Eurographics 2014.

  2. Sung-eui Yoon, Enrico Gobbetti, David Kasik, and Dinesh Manocha. Real-time Massive Model Rendering. Volume 2 of Synthesis Lectures on Computer Graphics and Animation, Morgan and Claypool, August 2008. https://doi.org/10.2200/S00131ED1V01Y200807CGR007.

  3. Enrico Gobbetti and Fabio Marton. Far Voxels - A Multiresolution Framework for Interactive Rendering of Huge Complex 3D Models on Commodity Graphics Platforms. ACM Transactions on Graphics, 24(3): 878-885, August 2005. Proc. SIGGRAPH 2005.

Massive volumetric compression and rendering. We focus on methods able to render models of potentially unlimited size on current GPU platforms. We introduced the first methods based on adaptive out-of-core multiresolution techniques with visibility feedback realized within a single-pass GPU raycasting framework, and introduced in this area novel compression techniques based on tensor decomposition and sparse coding. Fully interactive performance has been demonstrated on datasets of many GVoxels.
Representative publications
  1. Marcos Balsa Rodriguez, Enrico Gobbetti, José Antonio Iglesias Guitián, Maxim Makhinya, Fabio Marton, Renato Pajarola, and Susanne Suter. State-of-the-art in Compressed GPU-Based Direct Volume Rendering. Computer Graphics Forum, 33(6): 77-100, September 2014. https://doi.org/10.1111/cgf.12280.

  2. Enrico Gobbetti, José Antonio Iglesias Guitián, and Fabio Marton. COVRA: A compression-domain output-sensitive volume rendering architecture based on a sparse representation of voxel blocks. Computer Graphics Forum, 31(3pt4): 1315-1324, 2012. https://doi.org/10.1111/j.1467-8659.2012.03124.x. Proc. Eurovis 2012.

  3. Susanne K. Suter, José Antonio Iglesias Guitián, Fabio Marton, Marco Agus, Andreas Elsener, Christoph P.E. Zollikofer, M. Gopi, Enrico Gobbetti, and Renato Pajarola. Interactive Multiscale Tensor Reconstruction for Multiresolution Volume Visualization. IEEE Transactions on Visualization and Computer Graphics, 2011. Proc. IEEE Visualization.

Interactive visualization on remote, web, and mobile devices. With the widespread availability of mobile graphics terminal and WebGL-enabled browsers, 3D graphics over the Internet is thriving. Our research strives to overcome the limits imposed by network boundwidth, low-powered devices, and script-based Internet browser by introducing compact object and scene representations that support high-quality rendering.
Representative publications
  1. Marco Di Benedetto, Fabio Ganovelli, Marcos Balsa Rodriguez, Alberto Jaspe Villanueva, Roberto Scopigno, and Enrico Gobbetti. ExploreMaps: Efficient Construction and Ubiquitous Exploration of Panoramic View Graphs of Complex 3D Environments. Computer Graphics Forum, 33(2): 459-468, 2014. https://doi.org/10.1111/cgf.12334. Proc. Eurographics 2014.

  2. Marcos Balsa Rodriguez, Enrico Gobbetti, Fabio Marton, and Alex Tinti. Compression-domain Seamless Multiresolution Visualization of Gigantic Meshes on Mobile Devices. In Proc. ACM Web3D International Symposium. Pages 99-107, June 2013. ACM Press. New York, NY, USA.

  3. Enrico Gobbetti, Fabio Marton, Marcos Balsa Rodriguez, Fabio Ganovelli, and Marco Di Benedetto. Adaptive Quad Patches: an Adaptive Regular Structure for Web Distribution and Adaptive Rendering of 3D Models. In Proc. ACM Web3D International Symposium. Pages 9-16, August 2012. ACM Press. New York, NY, USA. (Best Long Paper Award).

Interactive visualization on novel light field displays. We focus on developing efficient techniques for harnessing the power of novel 3D display design. We work with Holografika (Hungary), that develops a 3D display combining a specially arranged array of projectors and a holographic screen. By properly controlling image generation, rendered objects appear floating in space to multiple naked eye viewers. Sustaining interactive rates is a challenging tasks, since hundreds of views per frame have to be generated. We develop specialized user interfaces, calibration methods, and surface and volume rendering techniques for both single processor and network parallel rendering.
Representative publications
  1. José Antonio Iglesias Guitián, Enrico Gobbetti, and Fabio Marton. View-dependent Exploration of Massive Volumetric Models on Large Scale Light Field Displays. The Visual Computer, 26(6--8): 1037-1047, 2010.

  2. Marco Agus, Enrico Gobbetti, José Antonio Iglesias Guitián, Fabio Marton, and Giovanni Pintore. GPU Accelerated Direct Volume Rendering on an Interactive Light Field Display. Computer Graphics Forum, 27(3): 231-240, 2008. Proc. Eurographics 2008.

  3. Fabio Bettio, Enrico Gobbetti, Fabio Marton, and Giovanni Pintore. Scalable Rendering of Massive Triangle Meshes on Light Field Displays. Computers & Graphics, 32(1): 55-64, February 2008.

Novel user interfaces for exploring 3D models. In the context of visualization of massive and complex scenes, users require interactive control to effectively explore the data. Our research focuses on natural interfaces for scene naviation and data exploration, exploiting the capabilities of input and output devices. In this area, we have introduced methods for constrained navigations using graphs, exploration tools for volumetric data, specialized techniques for camera control on touch screens, and user-interface techniques using dual-display setups.
Representative publications
  1. Fabio Marton, Marcos Balsa Rodriguez, Fabio Bettio, Marco Agus, Alberto Jaspe Villanueva, and Enrico Gobbetti. IsoCam: Interactive Visual Exploration of Massive Cultural Heritage Models on Large Projection Setups. ACM Journal on Computing and Cultural Heritage, 7(2): Article 12, June 2014.

  2. Fabio Marton, Marco Agus, Enrico Gobbetti, Giovanni Pintore, and Marcos Balsa Rodriguez. Natural exploration of 3D massive models on large-scale light field displays using the FOX proximal navigation technique. Computers & Graphics, 36(8): 893-903, December 2012. https://doi.org/10.1016/j.bbr.2011.03.031.

Real-time surgical simulation with visual and haptic feedback. We develop enabling technology to support surgical training through simulation. Our results so far include a multiresolution volumetric model for simulating bone burring, simplified models for contrast agent transport in human vessels, real-time techniques for phacoemulsification simulation. Some of our simulation and rendering modules have been integrated in industrial systems for surgical training.
Representative publications
  1. Marco Agus, Fabio Bettio, Andrea Giachetti, Enrico Gobbetti, José Antonio Iglesias Guitián, Fabio Marton, Jonas Nilsson, and Giovanni Pintore. An interactive 3D medical visualization system based on a light field display. The Visual Computer, 25(9): 883-893, 2009. https://doi.org/10.1007/s00371-009-0311-y.

  2. Marco Agus, Enrico Gobbetti, Giovanni Pintore, Gianluigi Zanetti, and Antonio Zorcolo. Real Time Simulation of Phaco-emulsification for Cataract Surgery Training. In Workshop in Virtual Reality Interactions and Physical Simulations (VRIPHYS 2006), November 2006. Eurographics Association. Conference held in Madrid, Spain, November 6-7.

  3. Marco Agus, Andrea Giachetti, Enrico Gobbetti, Gianluigi Zanetti, and Antonio Zorcolo. Real-time Haptic and Visual Simulation of Bone Dissection. Presence: Teleoperators and Virtual Environments, 12(1): 110-122, February 2003.

Many of our research results have been used in as diverse real-world applications as cultural heritage presentation, internet geoviewing, scientific data analysis, and surgical training. Examples of specific technology transfer actions are the following:

  • Cultural heritage exploration: our large-scale projection-based interactive system for exploring 3D cultural heritage objects is the basis for permanent exhibitions on Mont’e Prama statues at the National Archaeological Museum in Cagliari, Italy and at the Civic Museum in Cabras, Italy. Tens of thousands of visitors have had the opportunity to play with the system.
  • Massive point cloud library: our tools for geometry processing, streaming, and rendering library for massive point clouds are incorporated in the systems commercialized by Gexcel.
  • SAR3D/RER3D framework: we developed an interactive multilayer internet geoviewing system based on our technology for compression, distribution, and rendering of textured terrain data. The system is used by regional governments (Sardinia, Emilia Romagna) for presenting geographical information.
  • Cataract surgery simulator: We devloped a real-time virtual reality simulator of cataract surgery. The system has been used for surgical training courses by DIES group.
  • Discontinuous Finite Element Visualization: Our techniques for interactive scientific visualization of Discontinuous Finite Element Visualization have been incorpored in a software used at ENEL for analyzing CFD simulations.
  • Check our projects, publications, and multimedia pages for more information on our activities.