Grafica 3D per i beni culturali: intro. 23 Febbraio 2015

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1 Grafica 3D per i beni culturali: intro 23 Febbraio

2 About me Nato: 03/01/1979 Laurea in Ingegneria delle Telecomunicazioni, Università di Genova : Collaboratore a Elios Labs, DIBE, Università di Genova ora: Ricercatore a Visual Computing Lab, ISTI-CNR, Pisa Phd in Ingegneria dell Informazione (2009) Interessi: lettura, sculture palloncini, attività circensi

3 Visual Computing Lab Circa 20 unità full time (ricercatori, stud. PhD, assegnisti ) + collaboratori e tesisti 3D Graphics for Cultural Heritage Interactive Graphics Geometry Processing 3

4 Obiettivi del corso Alla fine del corso dovreste: Conoscere i possibili approcci per l acquisizione 3D di oggetti Dato un caso reale, capire quale sia la migliore tecnologia da applicare Saper usare alcuni software, principalmente freeware Essere in grado di progettare, eseguire e presentare un piccolo progetto di acquisizione 4

5 Prerequisiti (all incirca) Per poter ottenere il massimo del corso dovreste: Avere una discreta conoscenza dell inglese Possedere un laptop (o al limite desktop a casa) Conoscere le regole base dell informatica ( Se non funziona, spegni e riaccendi ) Avere voglia di smanettare sui dati anche fuori dalle lezioni 5

6 Prerequisiti (sondaggio) Avete già esperienza in: Programmazione (C++, Java, Javascript) Image editing 3D Modeling Modellazione da immagini Principi di fotografia? 6

7 Info pratiche Lezioni: Lunedì Lab M Giovedì Lab I Ricevimento su appuntamento (vedi contatti) Esame finale: preparazione ed esecuzione di un piccolo progetto di acquisizione, presentato in una pagina web + Piccolo test bonus/malus 7

8 Programma del corso (ordine sparso ) 3D graphics intro: 3D vs 2D, modelli di rappresentazione, the rendering pipeline Relightable images (RTI): Relightable Images, Polynomial Texture Maps, esempi 3D Scanning: intro, theory and practice; sistemi 3D scanning, data processing Mesh processing basics: theory and practice, navigazione, pulizia, re-meshing, coloring... MeshLab laboratory Assisted modeling from images: theory and practice, photogrammetry basics, image based modeling, tools commerciail, the Sketch-up approach, Sketch-up laboratory 3D reconstruction from images: theory and practice, dense stereo matching, Arc3D ebundler, data processing, Arc3D/Photosynth/Bundler + MeshLab laboratory Color information in acquisition : theory and practice, cos è il colore, BRDF et similia, image alignment, proiezione colore, texture mapping and color per vertex, MeshLab laboratory WebGL and 3D on the web Advanced visualization: shaders, multirisoluzione Case studies, projects and success stories: Photocity, 3D Warehouse di Google, Cenobium, progeti del Visual Computing Lab, etc etc 8

9 Software tools: MeshLab: PhotoCloud: SfMToolkit: VisualSfM: u/vsfm/doc.html PhotosynthToolkit: / RTIViewer: 3DHop: 9

10 Websites d interesse: MeshLab: Meshlab stuff: Visual Experiments: Photosynth: Photocity: Cultural Heritage Imaging: 10

11 Acquisire modelli 3D visually rich Obiettivo: Costruire modelli 3D accurati ricostruendo la geometria e le caratteristiche di superficie Metodi di acquisizione: Image-based Rendering Panoramic images: 2D model! Modellazione standard Image-based Modeling Blocky or low-res 3D models 3D scanning 3D da immagini (stereomatching) 11

12 Modelling vs. Acquiring Modelling Manual process [art] Unknown accuracy complete, nice model primitives? Acquiring Semi-automatic process [photograpy] Accuracy can be estimated Incomplete 3D model (holes, missing parts)

13 CAD-like modelling standard CAD modeling tools: Quite complex to use CAD modeling model accuracy essentially unknown Raffaello s Apartments and S. Peter Basilica, by InfoByte - Italy 13

14 Manual modelling A model obtained with photogrammetry and texture redesign on the basis of digital images (by Francesco Gabellone - IBAM-CNR) 14

15 3D acquisition: a taxonomy Contact Distance Articulated arms Slicing Optical Non optical Active Passive

16 3D Scanning

17 Multi-view stereo matching Images (C) by Maurizio Forte

18 Image-based Modeling Image-based Modeling (I-BM) Essentially it s a compromise between manual modelling and multi-view stereo matching User-assisted Mainly architectural models Simple structures 18

19 Basic (...) usage of 3D Scanning Torre Rognosa, San Gimignano Progetto 3D acquisition, sensors network to measure sveral factors and help the monitoring og the tower

20 Analyses on geometry

21 Structural analysis The 3D model was (severely) simplified to be able to perform finite elements structural analysis

22 Not so basic usage of 3D scanning Madonna of Pietranico: the 3D model was used to design a complex support structure to allow a reversible, non invasive reassembling of the pieces

23 Basic usage of Multi-view stereo matching Building Rome in a (cloudless) day

24 Not so basic usage of Multi-view stereo matching The reconstruction of Bamiyan Buddha 24

25 3D data (and life) are what you make of them

26 La badia Camaldolese, Volterra

27 La badia Camaldolese, Volterra

28 La badia Camaldolese, Volterra

29 La badia Camaldolese, Volterra

30 3D Printing and rapid prototyping Museo Archeologico Gaio Clinio Mecenate (Arezzo) A high detail reproduction of the portrait of Mecenate No contact copy is possible anymore in Italy => Range scanning 3D and 3D printing!

31 Reconstruction of original policromy Classic (Roman and Greek, and others) statuary: Acquisition of 3D Models Surveying and analysis of color remains Digital recoloring of statues

32 The Pompei Scanning Project Collaboration with University of Lund Range scanning insula V 3D data used for: - 3D modelling of original house - Exploration with cave - Experimenting new ways to remotely navigate models - Full integration with GIS

33 Documenting archeology excavations 33

34 Visito Tuscany project Uses of technologies and hidden 3D context to support the tourist before, during and after the visit

35 L.O.V.E., Escher, Passi and 35

36 Not only 3D: RTI Imaging Virtual museums for objects which are hard to acquire with usual 3D acquisition methods - Il monetiere di Palazzo Blu a Pisa

37 Conclusions, some open issues - 3D Scanning vs. 3D from images - Bridging the gap between acquisition and modeling - Web visualization - The communication of content - Use of mobile, personalized storytelling, wisdom of crowds - 3D printing!! - Color! 37

38 Nella prossima puntata Prossima lezione: 3D basics: 3D vs. 2D, 3D models format, rendering pipeline (con guest star) Contatti: Matteo Dellepiane c/o ISTI-CNR Via G. Moruzzi Pisa (PI) Tel dellepiane@isti.cnr.it Personal website: VCG website: