It also addresses a new basic research problem: how can we automate the geo- metric reasoning (consistency, integration of diverse types of information, . The goal is to recover 3D scene structure under different assumptions: — Unknown camera parameters and scenes: the basic structure of uncalibrated multi-camera geometry has been well studied in the past, so here we focus on a unification of the theory on one side, and practical numerical methods on the other; — Partial camera or scene knowledge: in many applications some prior infor- mation is available are image-equivalent is a twisted cubic passing through El, . Two- View Ambiguity The basic (0) result about critical surfaces from two views may be stated as follows. A configuration of two camera centres and n points allows an alternative reconstruction if and only if both camera centres Ci, C 2 and all the points Xj lie on a ruled quadric surface.
Furthermore, when an alternative reconstruction exists, then there will always exist a third distinct reconstruction. , C„ and all the points Xi, Xg lie on a ruled quadric surface.
Much of the work reported here is to be seen especially against the background of a convergence between computer vision and computer graphics, and of a shift from signal-based to content-based image analysis in telecommunications.
Ac- cordingly, the requirements for 3D models and acquisition systems are also shift- ing.
First, an overview is given of the work performed in the three organizing projects with links to the related contributions.
In his invited presentation, Richard Hartley then develops ideas to exploit the duality concept between points and cameras in scene reconstruction.
Interaction with the modeled scene and mixing of virtual and real objects leads to Vir- tual/Augmented Reality applications in Vanguard and Cumuli, while the Panorama approach is tuned to fully automatic scene analysis for vi- sual communication and 3D-telepresence. and the vertices of the reference tetrahedron are projected in the same way relative to the two projection centres.
Visualisation aspects are han- dled by Vanguard and Panorama with the development of auto-stereo- scopic displays. On the industrial side, CUMULi’s partners have expertise in image-based metrology: Innovativ Vision Image Systems in Linkoping are specialists in motion measurement from high speed image se- quences, e.g. laboratory in Grenoble has also joined the academic team, bringing his expertise in algebraic proof for geometry. That is, is image-equivalent to for all X on the twisted cubic.Visualization rather than mensuration is the primary issue.The perceptual quality of the models, the flexibility of the acquisition, and the cost of the system are three driving forces in the search for new methods.1506) ISBN 3-540-65310-4 CR Subject Classification (1998): 1.4, 1.2.10, 1.5.4 ISSN 0302-9743 ISBN 3-540-65310-4 Springer- Verlag Berlin Heidelberg New York This work is subject to copyright.All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in any other way, and storage in data banks.The same developments also hold good promise to make 3D acquisition cheaper and more widely available.