13,903 research outputs found

    Highly detailed 3D modelling of Mayan cultural heritage using an UAV

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    A semantic-based platform for the digital analysis of architectural heritage

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    This essay focuses on the fields of architectural documentation and digital representation. We present a research paper concerning the development of an information system at the scale of architecture, taking into account the relationships that can be established between the representation of buildings (shape, dimension, state of conservation, hypothetical restitution) and heterogeneous information about various fields (such as the technical, the documentary or still the historical one). The proposed approach aims to organize multiple representations (and associated information) around a semantic description model with the goal of defining a system for the multi-field analysis of buildings

    From survey to fem analysis for documentation of built heritage: The case study of villa revedin-bolasco

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    In the last decade advances in the fields of close-range photogrammetry, terrestrial laser scanning (TLS) and Computer Vision (CV) have enabled to collect different kind of information about a Cultural Heritage objects and to carry out highly accurate 3D models. Additionally, the integration between laser scanning technology and Finite Element Analysis (FEA) is gaining particular interest in recent years for structural analysis of built heritage, since the increasing computational capabilities allow to manipulate large datasets. In this note we illustrate the approach adopted for surveying, 3D modeling and structural analysis of Villa Revedin-Bolasco, a magnificent historical building located in the small walled town of Castelfranco Veneto, in northern Italy. In 2012 CIRGEO was charged by the University of Padova to carry out a survey of the Villa and Park, as preliminary step for subsequent restoration works. The inner geometry of the Villa was captured with two Leica Disto D3a BT hand-held laser meters, while the outer walls of the building were surveyed with a Leica C10 and a Faro Focus 3D 120 terrestrial laser scanners. Ancillary GNSS measurements were also collected for 3D laser model georeferencing. A solid model was then generated from the laser global point cloud in Rhinoceros software, and portion of it was used for simulation in a Finite Element Analysis (FEA). In the paper we discuss in detail all the steps and challenges addressed and solutions adopted concerning the survey, solid modeling and FEA from laser scanning data of the historical complex of Villa Revedin-Bolasco

    Fisheye Photogrammetry to Survey Narrow Spaces in Architecture and a Hypogea Environment

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    Nowadays, the increasing computation power of commercial grade processors has actively led to a vast spreading of image-based reconstruction software as well as its application in different disciplines. As a result, new frontiers regarding the use of photogrammetry in a vast range of investigation activities are being explored. This paper investigates the implementation of fisheye lenses in non-classical survey activities along with the related problematics. Fisheye lenses are outstanding because of their large field of view. This characteristic alone can be a game changer in reducing the amount of data required, thus speeding up the photogrammetric process when needed. Although they come at a cost, field of view (FOV), speed and manoeuvrability are key to the success of those optics as shown by two of the presented case studies: the survey of a very narrow spiral staircase located in the Duomo di Milano and the survey of a very narrow hypogea structure in Rome. A third case study, which deals with low-cost sensors, shows the metric evaluation of a commercial spherical camera equipped with fisheye lenses

    Structure from motion systems for architectural heritage. A survey of the internal loggia courtyard of Palazzo dei Capitani, Ascoli Piceno, Italy

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    We present the results of a point-cloud-based survey deriving from the use of image-based techniques, in particular with multi-image monoscopic digital photogrammetry systems and software, the so-called “structure-from-motion” technique. The aim is to evaluate the advantages and limitations of such procedures in architectural surveying, particularly in conditions that are “at the limit”. A particular case study was chosen: the courtyard of Palazzo dei Capitani del Popolo in Ascoli Piceno, Italy, which can be considered the ideal example due to its notable vertical, rather than horizontal, layout. In this context, by comparing and evaluating the different results, we present experimentation regarding this single case study with the aim of identifying the best workflow to realise a complex, articulated set of representations—using 3D modelling and 2D processing—necessary to correctly document the particular characteristics of such an architectural object

    Heritage Recording and 3D Modeling with Photogrammetry and 3D Scanning

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    The importance of landscape and heritage recording and documentation with optical remote sensing sensors is well recognized at international level. The continuous development of new sensors, data capture methodologies and multi-resolution 3D representations, contributes significantly to the digital 3D documentation, mapping, conservation and representation of landscapes and heritages and to the growth of research in this field. This article reviews the actual optical 3D measurement sensors and 3D modeling techniques, with their limitations and potentialities, requirements and specifications. Examples of 3D surveying and modeling of heritage sites and objects are also shown throughout the paper

    COMPUTER AIDED RESTORATION TOOLS TO ASSIST THE CONSERVATION OF AN ANCIENT SCULPTURE. THE COLOSSAL STATUE OF ZEUS ENTHRONED

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    The research focuses on the contribution of the integrated application of Computer Aided Restoration digital procedures as a means to guide the integration measure of an artifact, innovating and implementing the traditional investigation methods. The aim of the study was to provide effective geometrical-formal investigation tools in the frame of the conservation work of Zeus enthroned from Soluntum, conserved in the Archaeological Museum \u201cA. Salinas\u201d of Palermo. The paper describes the workflow of the 3D acquisition and graphical modeling with non-invasive digitalization and high information density techniques to assist the conservation of the legs of the throne, especially the integration of the missing part. Thanks to the technique of the digital fabrication it has been reconstruct the two missing parts following the theoretical criteria as: recognisability, compatibility and retractability. This innovative application of 3D digital technologies have showed as the integrated use of the new technology can be a useful tools for improving the conservation of a work of art

    Fuentes de color mejoradas para el modelado tridimensional de artefactos arqueológicos de tamaño medio localizados in situ.

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    [EN] The paper describes a color enhanced processing system - applied as case study on an artifact of the Pompeii archaeological area - developed in order to enhance different techniques for reality-based 3D models construction and visualization of archaeological artifacts. This processing allows rendering reflectance properties with perceptual fidelity on a consumer display and presents two main improvements over existing techniques: a. the color definition of the archaeological artifacts; b. the comparison between the range-based and photogrammetry-based pipelines to understand the limits of use and suitability to specific objects.[ES] El documento describe un sistema mejorado de procesamiento de color, aplicado como caso de estudio sobre un artefacto de la zona arqueológica de Pompeya. Este sistema se ha desarrollado con la finalidad de mejorar las diferentes técnicas para la construcción de modelos 3D basados sobre datos de la realidad y para la visualización de artefactos arqueológicos. Este proceso permite visualizar las propiedades de reflectancia con fidelidad perceptible en una pantalla de usuario y presenta dos mejoras principales respecto a las técnicas existentes:a. la definición del color de los artefactos arqueológicos;b. la comparación entre los flujos de trabajo basados en range-based-modeling y en fotogrametría, para entender los límites de uso y la adecuación a los objetos específicos.Apollonio, FI.; Ballabeni, M.; Gaiani, M. (2014). Color enhanced pipelines for reality-based 3D modeling of on site medium sized archeological artifacts. Virtual Archaeology Review. 5(10):59-76. https://doi.org/10.4995/var.2014.4218OJS5976510AGISOFT PHOTOSCAN (2014), http://www.agisoft.ru.ALLEN P., FEINER S., et al. 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(eds), Recording, Modeling and Visualization of Cultural Heritage, Taylor & Francis.BOOCHS F., BENTKOWSKA-KAFEL A., et al. (2013): "Towards optimal spectral and spatial documentation of Cultural Heritage. COSCH - an interdisciplinary action in the COST framework", in ISPRS Arch., Vol. XL-5/W2, 2013, pp. 109-113.CALLIERI M., CIGNONI P., et al. (2008): "Masked photo blending: mapping dense photographic dataset on high-resolution 3D models", in Computer & Graphics, Vol. 32, N. 4, 2008, pp. 464 - 473.CALLIERI M., DELLEPIANE M., et al. (2011): "Processing Sampled 3D Data: Reconstruction and Visualization Technologies", in F. Stanco, S. Battiato, G. Gallo (eds.), Digital Imaging for Cultural Heritage Preservation: Analysis, Restoration and Reconstruction of Ancient Artworks, Taylor and Francis, pp. 105-136.CORSINI M., DELLEPIANE M., et al. (2009):"Image-to-geometry registration: a mutual information method exploiting illumination-related geometric properties", in Computer Graphics Forum, Vol. 28, N. 7, 2009, pp. 1755-1764. http://dx.doi.org/10.1111/j.1467-8659.2009.01552.xDANA K.J., VAN GINNEKEN B., et al.. (1999): "Reflectance and texture of real-world surfaces", in ACM Transaction on Graphics, Vol. 18, N. 1, 1999, pp. 1-34. http://dx.doi.org/10.1145/300776.300778DE LUCA L., VERON P., FLORENZANO M. (2006): "Reverse engineering of architectural buildings based on a hybrid modeling approach", Computer & Graphics, Vol. 30, N. 2, pp. 160-76. http://dx.doi.org/10.1016/j.cag.2006.01.020DEBEVEC P. et al. (2004): "Estimating surface reflectance properties of a complex scene under captured natural illumination", in USC ICT Technical Report ICT-TR, 06/2004.DELLEPIANE M., MARROQUIM R., et al. (2012): "Flow-Based Local Optimization for Image-to-Geometry Projection", in IEEE Transactions on Visualization and Computer Graphics, Vol. 18, N. 3, 2012, pp. 463-474. http://dx.doi.org/10.1109/TVCG.2011.75DELLEPIANE M., DELL'UNTO N., et al. (2013a): "Archeological excavation monitoring using dense stereo matching techniques", in Journal of Cultural Heritage, Vol. 14, N. 3, 2013, pp. 201-210. http://dx.doi.org/10.1016/j.culher.2012.01.011DELLEPIANE M., SCOPIGNO R. (2013b): "Global refinement of image-to-geometry registration for color projection", in DigitalHeritage 2013 Proceedings, 2013, Vol. 1, pp. 39-46.DXO (2014), http://www.dxo.com/intl/photography/dxo-optics-pro/EL-HAKIM S.F., BRENNER C., ROTH G. (1998): "A multi-sensor approach to creating accurate virtual environments", in ISPRS Journal of Photogrammetry and Remote Sensing, Vol. 53, N. 6, pp. 379-391. http://dx.doi.org/10.1016/S0924-2716(98)00021-5EL-HAKIM S.F., BERALDIN J.-A., et al. (2004): "Detailed 3D reconstruction of large-scale heritage sites with integrated techniques", in Computer Graphics and Applications, Vol. 24, N. 3, 2004, pp. 21-29. http://dx.doi.org/10.1109/MCG.2004.1318815EL-HAKIM S.F., BERALDIN J.-A. (2007): "Sensor integration and visualization", in Fryer, Mitchell & Chandler (eds.), Applications of 3D Measurement from Images, Whittles Publishing, pp. 259-298.ENGLISH HERITAGE (2005): Metric Survey Specifications for English Heritage. English Heritage Report.ENGLISH HERITAGE (2011), 3D Laser Scanning for Heritage (second edition), English Heritage Publishing.FURUKAWA Y., PONCE J. (2010): "Accurate, dense, and robust multi-view stereopsis", in IEEE Transactions on Pattern Analysis and Machine Intelligence Vol. 32, N. 8, pp. 1362-1376. http://dx.doi.org/10.1109/TPAMI.2009.161GAIANI M., MICOLI L.L. (2005): "A framework to build and visualize 3D models from real world data for historical architecture and archaeology as a base for a 3D information system", in Forte M. (a cura di), The reconstruction of Archaeological Landscapes through Digital Technologies, BAR International series, 1379, pp. 103-125.GAIANI M., ROSSI M., RIZZI A. (2003): "Percezione delle immagini virtuali", in M. Gaiani (ed.), Metodi di Prototipazione Digitale e Visualizzazione per il Disegno Industriale, l'Architettura degli Interni e i Beni Culturali, Polidesign, Milano, 2003.GAIANI M., BENEDETTI B., REMONDINO F. (eds) (2010): Modelli digitali 3D in archeologia: il caso di Pompei, Edizioni della Normale, Pisa, 2010.GAŠPAROVIC M., MALARIC I. (2012): "Increase of readability and accuracy of 3D models using fusion of Close Range Photogrammetry and Laser Scanning", in ISPRS Arch. Photogramm. Remote Sens., Vol. XXXIX-B5, pp. 93-98.GODIN G., BORGEAT L., et al. (2010): "Issues in Acquiring, Processing and Visualizing Large and Detailed 3D Models", in Information Sciences and Systems (CISS), 44th Annual Conference on, pp.1-6. http://dx.doi.org/10.1109/ciss.2010.5464966GONIZZI BARSANTI S., MICOLI L.L., GUIDI G. (2013a): "Quick textured mesh generation for massive 3D digitization of museum artifacts", in DigitalHeritage 2013, Vol. 1, pp. 197-200.GONIZZI BARSANTI S., REMONDINO F., VISINTINI D. (2013b): "3D surveying and modeling of archaeological sites - some critical issues", in ISPRS Ann. Photogramm. Remote Sens., Vol. II-5/W1, 2013, pp. 145-150.GRUSSENMEYER P., LANDES T., et al. (2008): "Comparison methods of terrestrial laser scanning, photogrammetry and tacheometry data for recording of cultural heritage buildings", in ISPRS Arch. Photogramm. Remote Sens., Vol. XXXVII/W5, pp. 213-218.GUARNIERI A., REMONDINO F., VETTORE A. (2006): "Digital photogrammetry and TLS data fusion applied to Cultural Heritage 3D modeling", in ISPRS Arch., Vol. XXXVI/W6, pp. 6.HAPPA J., BASHFORD-ROGERS T., et al. (2012): "Cultural Heritage Predictive Rendering", in Computer Graphics Forum, Vol. 31, N. 6, 2012, pp. 1823-1836. http://dx.doi.org/10.1111/j.1467-8659.2012.02098.xHIRSCHMÜLLER H. (2005): "Accurate and efficient stereo processing by semi-global matching and mututal information", in CVPR 2005 proceedings, Vol. 2, pp. 807-814.HIRSCHMUELLER H. (2008): "Stereo processing by semi- global matching and mutual information", in IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 30, N. 2, pp. 328-41. http://dx.doi.org/10.1109/TPAMI.2007.1166KARSIDAG G., ALKAN R.M. (2012): "Analysis of The Accuracy of Terrestrial Laser Scanning Measurements", in FIG Working Week 2012 - Knowing to manage the territory, protect the environment, evaluate the cultural heritage proceedings, TS07A - Laser Scanners I, 6097.KAWAKAMI R., IKEUCHI K., TAN R.T. (2005): "Consistent surface color for texturing large objects in outdoor scenes", in ICCV 2005 proceedings, Vol. 2, 2005, pp. 1200-1207.IMATEST (2014), http://www.imatest.com/homeIMAGENOMIC LLC (2012): Noiseware 5 Plug-In User's Guide, 2012INNOVMETRIC POLYWORKS (2014): http://www.innovmetric.com/polyworks/Surveying/LENSCH H.P.A., KAUTZ J., et al. (2003): "Image-based reconstruction of spatial appearance and geometric detail", in ACM Trans. Graph., Vol. 22, N. 2, 2003, pp. 234-257. http://dx.doi.org/10.1145/636886.636891LOWE D. (2004): "Distinctive image features from scale-invariant keypoints", in IJCV, Vol. 60, N. 2, 2004, pp. 91-110.MESHLAB (2014): http://meshlab.sourceforge.net/MUDGE M., SCHROER C., et al. 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    Multispectral RTI Analysis of Heterogeneous Artworks

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    We propose a novel multi-spectral reflectance transformation imaging (MS-RTI) framework for the acquisition and direct analysis of the reflectance behavior of heterogeneous artworks. Starting from free-form acquisitions, we compute per-pixel calibrated multi-spectral appearance profiles, which associate a reflectance value to each sampled light direction and frequency. Visualization, relighting, and feature extraction is performed directly on appearance profile data, applying scattered data interpolation based on Radial Basis Functions to estimate per-pixel reflectance from novel lighting directions. We demonstrate how the proposed solution can convey more insights on the object materials and geometric details compared to classical multi-light methods that rely on low-frequency analytical model fitting eventually mixed with a separate handling of high-frequency components, hence requiring constraining priors on material behavior. The flexibility of our approach is illustrated on two heterogeneous case studies, a painting and a dark shiny metallic sculpture, that showcase feature extraction, visualization, and analysis of high-frequency properties of artworks using multi-light, multi-spectral (Visible, UV and IR) acquisitions.Terms: "European Union (EU)" & "Horizon 2020" / Action: H2020-EU.3.6.3. - Reflective societies - cultural heritage and European identity / Acronym: Scan4Reco / Grant number: 665091the DSURF (PRIN 2015) project funded by the Italian Ministry of University and ResearchSardinian Regional Authorities under projects VIGEC and Vis&VideoLa
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