Sampled 3D models for Cultural Heritage: which uses beyond visualization?

[EN] Digital technologies are now mature for producing high quality digital replicas of Cultural Heritage (CH) artefacts. The research results produced in the last decade have shown an impressive evolution and consolidation of the technologies for acquiring high-quality digital 3D models (3D scanning) and for rendering those models at interactive speed. Technology is now mature enough to push us to go beyond the plain visualization of those assets, devising new tools able to extend our insight and intervention capabilities and to revise the current consolidated procedures for CH research and management. The paper presents a few recent experiences where high-quality 3D models have been used in CH research, restoration and conservation. These examples constitutes a broad review of different uses of digital 3Dassets in the CH domain.[ES] Se puede afirmar que las tecnologías digitales han alcanzado un punto de madurez suficiente como para producir réplicas digitales de alta calidad del patrimonio cultural, especialmente de artefactos. Los resultados de la investigación producidos en la última década han mostrado una impresionante evolución y consolidación de las tecnologías utilizadas para la producción de modelos digitales 3D de alta calidad (escaneado 3D) y para el renderizado de esos modelos a una velocidad interactiva. En este sentido la tecnología es hoy perfectamente capaz de empujarnos a ir más allá de la simple visualización de los bienes culturales, hasta elaborar nuevas herramientas capaces de ampliar nuestra visión y capacidades de intervención así como de revisar los procedimientos actuales de investigación y gestión del patrimonio cultural. Este artículo presenta algunas experiencias recientes en las que modelos 3D de alta calidad han sido utilizados para mejorar la investigación, restauración y conservacióThe research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007- 2013) under grant agreements no. 231809 (IST IP "3DCOFORM") and no. 270404 (IST NoE "V-Must.Net").Scopigno, R. (2012). Sampled 3D models for Cultural Heritage: which uses beyond visualization?. Virtual Archaeology Review. 3(5):109-115. https://doi.org/10.4995/var.2012.4537OJS10911535CALLIERI M., CIGNONI P., GANOVELLI F., IMPOCO G., MONTANI C., PINGI P., PONCHIO F., SCOPIGNO R. (2004): "Visualization and 3D data processing in David's restoration". IEEE Computer Graphics & Applications 24, 2 (Mar.-Apr. 2004), pp. 16-21. http://dx.doi.org/10.1109/MCG.2004.1274056CORSINI M., DELLEPIANE M., DERCKS U., PONCHIO F., CALLIERI M., KEULTJES D., MARINELLO A., SIGISMONDI R., SCOPIGNO R., WOLF G. (2010): "Cenobium - putting together the romanesque cloister capitals of the mediterranean region". In Bar International Series BAR S2118 2010 (Proc. of III International Conference on Remote Sensing in Archaeology, 17th-21st August 2009) (2010), S. Campana M. F., Liuzza C., (Eds.), pp. 189-194.DELLEPIANE M., CALIERI M., DELL'UNTO N. (2011): "Monitoring archeological excavation using dense stereo matching techniques". Tech. rep., CNR-ISTI, Pisa, Italy, 2011.DELLEPIANE M., CALLIERI M., FONDERSMITH M., CIGNONI P., SCOPIGNO R. (2007): "Using 3D scanning to analyze a proposal for the attribution of a bronze horse to Leonardo da Vinci". In The 8th Int. Symp. on International Symposium on Virtual Reality, Archaeology and Cultural Heritage (VAST 07) (Nov 2007), Eurographics, pp. 117-124.DYLLA K., FRISCHER B., MUELLER P., ULMER A., HAEGLER S. (2009): "Rome Reborn 2.0: A case study of virtual city reconstruction using procedural modeling techniques". In 37th Proceedings of the CAA Conference, March 22-26, 2009 (2009), pp. 62-66.HUANG Q.-X., FLORY S., GELFAND N., HOFER M., POTTMANN H. (2006): "Reassembling fractured objects by geometric matching". ACM Trans. Graphics 25, 3 (2006), pp. 569-578. http://dx.doi.org/10.1145/1141911.1141925LEVOY M., PULLI K., CURLESS B., RUSINKIEWICZ S., KOLLER D., PEREIRA L., GINZTON M., ANDERSON S., DAVIS J., GINSBERG J., SHADE J., FULK D. (2000): "The Digital Michelangelo Project: 3D scanning of large statues". In SIGGRAPH 2000, Computer Graphics Proceedings (July 24-28, 2000), Annual Conference Series, AddisonWesley, pp. 131-144. http://dx.doi.org/10.1145/344779.344849SCOPIGNO, Roberto et al. (2011): "Sampled 3D models for CH: beyond plain visualization", IEEE Computer, IEEE Press, July-Aug. 2011, (in press).STANCO F., BATTIATO S., GALLO G., (ed.) (2011): "Digital Imaging for Cultural Heritage Preservation". Taylor & Francis Group, 2011.TOLER-FRANKLIN C., BROWN B., WEYRICH T., FUNKHOUSER T., RUSINKIEWICZ S. (2010): "Multi-feature matching of fresco fragments". ACM Trans. Graphics (Proc. SIGGRAPH Asia) 29, 6 (2010), pp. 185-197. http://dx.doi.org/10.1145/1882262.1866207http://dx.doi.org/10.1145/1882261.186620

Image Guided Reconstruction of Un-sampled Data: A Filling Technique for Cultural Heritage Models

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Visibility based methods and assessment for detail-recovery

In this paper we propose a new method for the creation of normal maps for recovering the detail on simpli\ufb01ed meshes and a set of objective techniques to metrically evaluate the quality of different recovering techniques. The proposed techniques, that automatically produces a normal-map texture for a simple 3D model that \u201cimitates\u201d the high frequency detail originally present in a second, much higher resolution one, is based on the computation of per-texel visibility and self-occlusion information. This information is used to de\ufb01ne a point-to-point correspondence between simpli\ufb01ed and hi-res meshes. Moreover, we introduce a number of criteria for measuring the quality (visual or otherwise) of a given mapping method, and provide ef\ufb01cient algorithms to implement them. Lastly, we apply them to rate different mapping methods, including the widely used ones and the new one proposed here

Shape enhancement for rapid prototyping

Many applications, for instance in the reverse engineering and cultural heritage field, require to build a physical replica of 3D digital models. Recent 3D printers can easily perform this task in a relatively short time and using color to reproduce object textures. However, the finite resolution of printers and, most of all, some peculiar optical and physical properties of the used materials reduce their perceptual quality. The contribution of this paper is a shape enhancing technique, which allows users to increase readability of the tiniest details in physical replicas, without requiring manual post-reproduction interventions.831-840Pubblicat

Real Time, Accurate, Multi-Featured Rendering of Bump Mapped Surfaces

We present a new technique to render in real time objects which have part of their high frequency geometric detail encoded in bump maps. It is based on the quantization of normal-maps, and achieves excellent result both in rendering time and rendering quality, with respect to other alternative methods. The method proposed also allows to add many interesting visual effects, even for object with large bumb maps, including non-photorealistic rendering, chrome effects, shading under multiple lights, rendering of different materials within a single object, specular reflections and others. Moreover, the implementation of the method is not complex and can be eased by software reuse

Preserving attribute values on simplified meshes by re-sampling detail textures

Many sophisticated solutions have been proposed to reduce the geometric complexity of 3D meshes. A slightly less studied problem is how to preserve attribute detail on simplified meshes (e.g., color, high-frequency shape details, scalar fields, etc.).We present a general approach that is completely independent of the simplification technique adopted to reduce the mesh size. We use resampled textures (rgb, bump, displacement or shade maps) to decouple attribute detail representation from geometry simplification. The original contribution is that preservation is performed after simplification by building a set of triangular texture patches that are then packed into a single texture map. This general solution can be applied to the output of any topology-preserving simplification code and it allows any attribute value defined on the high-resolution mesh to be recovered. Moreover, decoupling shape simplification from detail preservation (and encoding the latter with texture maps) leads to high simplification rates and highly efficient rendering. We also describe an alternative application: the conversion of 3D models with 3D procedural textures (which generally force the use of software renderers) into standard 3D models with 2D bitmap textures

Distribución y uso de modelos 3D en la web: ¿estamos listos?

[EN] Digital technologies are now mature for producing high quality digital replicas of Cultural Heritage (CH) assets. The research results produced in the last decade ignitedan impressive evolution and consolidation of the technologies for acquiring high-quality digital three-dimensional (3D)models, encompassing both geometry and color. What remains still an open problem is how to deliver those data and related knowledge to our society. The web is nowadays the main channel for the dissemination of knowledge. Emerging commercial solutions for web-publishing of 3D data are consolidating and becoming a de-facto standard for many applications(e-commerce, industrial products, education, etc.).In this framework, CH is a very specific domain, requiring highly flexible solutions. Some recent experiences arepresented, aimed at providing a support to the archival of archaeological3Ddata, supporting web-based publishing of very high-resolution digitization results and finally enabling the documentation of complex restoration actions. All those examples have been recently implemented on the open-source 3D Heritage Online Presenter (3DHOP)platform, developed at CNR-ISTI[ES] Las tecnologías digitales estánahora maduraspara producir réplicas digitales de alta calidad de valores activos del patrimonio cultural (CH). Los resultados de la investigación producidos en la última década han mostrado una evolución impresionante y una consolidación de las tecnologías para la capturade modelos digitales tridimensionales (3D)de alta calidad, que abarcanla geometríay el color.Lo que queda aún por resolver estárelacionado con la forma de distribuirlos datos y el conocimiento relacionado conla sociedad. La web es hoy en día el principal canal utilizado para divulgarel conocimiento. Las soluciones comerciales nuevas relacionadas con la publicación en la red de datos en 3D se están consolidando y convirtiendo en un estándar de facto para muchas aplicaciones(comercio electrónico, productos industriales, educación, etc.). En este escenario, el patrimonio culturales un dominio muy específico, que requiere soluciones muyflexibles.Se presentan algunas experiencias recientes, destinadasa proporcionar un apoyo al archivo de los datos arqueológicos3D, la publicaciónwebde los resultados de digitalización de muy alta resoluciónque permitenfinalmente la documentación de trabajos de restauracióncomplejos. Todos estos ejemplos se han implementado recientemente en la plataforma 3D Heritage Online Presenter(3DHOP)de código abierto, desarrolladaen el CNR-ISTI.The research leading to these results has received funding from the EU 7th Framework Programme (FP7/2007-2013) under grant agreement no. 654119 (EC "PARTHENOS" project) and EU H2020 Programme (“EMOTIVE: EMOTIve Virtual cultural Experiences through personalized storytelling”, H2020-SC6-CULT-COOP-08-2016) under grant agreement no. 727188.Scopigno, R.; Callieri, M.; Dellepiane, M.; Ponchio, F.; Potenziani, M. (2017). Delivering and using 3D models on the web: are we ready?. Virtual Archaeology Review. 8(17):1-9. https://doi.org/10.4995/var.2017.6405SWORD1981

Simulating Populations in Massive Urban Environments

This short paper reviews some of the results obtained withing the European Project CRIMSON.The United Nations recently reported that the global proportion of urban population reached 49% in 2005 and that 60% of the global population is expected to live in cities by 2030. Urbanised areas are extremely vulnerable to all sorts of threats. Indeed, the combination of heavy population concentrations, critical infrastructures and built environments make it possible for environmental, industrial or man-made incidents to rapidly escalate into major disorders. Recent events have forcefully demonstrated that authorities at all levels of government turn out to be inadequately prepared for the intricacies and dilemmas of disasters in large urban environments. Therefore, innovative tools are needed to assist them in the studies, planning and inter-organizational preparation efforts, enabling to understand vulnerabilities and security issues, define and assess crisis management procedures, and train personnel. The CRIMSON research project has been funded by the European Commission in the field of Security Research to address this challenging need by researching, implementing and validating an innovative framework combining the latest virtual reality and simulation technologies. For that purpose, several technological challenges have been tackled by an international team of researchers, industrials and users, and important advances have been made in the following fields

Interactive Out-of-core Visualization of Very Large Landscapes on Commodity Graphics Platforms

We recently introduced an efficient technique for out-of-core rendering and management of large textured landscapes. The technique, called Batched Dynamic Adaptive Meshes (BDAM), is based on a paired tree structure: a tiled quadtree for texture data and a pair of bintrees of small triangular patches for the geometry. These small patches are TINs that are constructed and optimized off-line with high quality simplification and tristripping algorithms. Hierarchical view frustum culling and view-dependendent texture/geometry refinement is performed at each frame with a stateless traversal algorithm that renders a continuous adaptive terrain surface by assembling out of core data. Thanks to the batched CPU/GPU communication model, the proposed technique is not processor intensive and fully harnesses the power of current graphics hardware. This paper summarizes the method and discusses the results obtained in a virtual flythrough over a textured digital landscape derived from aerial imaging.21-2