ETD

Archivio digitale delle tesi discusse presso l'Università di Pisa

Tesi etd-05212013-172635


Tipo di tesi
Tesi di dottorato di ricerca
Autore
PALMA, GIANPAOLO
URN
etd-05212013-172635
Titolo
Surface Appearance Estimation from Video Sequences
Settore scientifico disciplinare
INF/01
Corso di studi
INFORMATICA
Relatori
tutor Dott. Scopigno, Roberto
tutor Dott. Callieri, Marco
Parole chiave
  • Video-to-Geometry Registration
  • SVBRDF
  • Surface Light Field
  • shading enhancement
  • RTI
Data inizio appello
07/06/2013
Consultabilità
Completa
Riassunto
The realistic virtual reproduction of real world objects using Computer Graphics techniques requires the accurate acquisition and reconstruction of both 3D geometry and surface appearance. Unfortunately, in several application contexts, such as Cultural Heritage (CH), the reflectance acquisition can be very challenging due to the type of object to acquire and the digitization conditions. Although several methods have been proposed for the acquisition of object reflectance, some intrinsic limitations still make its acquisition a complex task for CH artworks: the use of specialized instruments (dome, special setup for camera and light source, etc.); the need of highly controlled acquisition environments, such as a dark room; the difficulty to extend to objects of arbitrary shape and size; the high level of expertise required to assess the quality of the acquisition.
The Ph.D. thesis proposes novel solutions for the acquisition and the estimation of the surface appearance in fixed and uncontrolled lighting conditions with several degree of approximations (from a perceived near diffuse color to a SVBRDF), taking advantage of the main features that
differentiate a video sequences from an unordered photos collections: the temporal coherence; the data redundancy; the easy of the acquisition, which allows acquisition of many views of the object in a short time. Finally, Reflectance Transformation Imaging (RTI) is an example of
widely used technology for the acquisition of the surface appearance in the CH field, even if limited to single view Reflectance Fields of nearly flat objects. In this context, the thesis addresses also two important issues in RTI usage: how to provide better and more flexible virtual inspection capabilities with a set of operators that improve the perception of details, features and overall shape of the artwork; how to increase the possibility to disseminate this data and to support remote visual inspection of both scholar and ordinary public.
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