Surface Reconstruction from 3D Scanning
This research area consists in general methods for automatic reconstruction
of accurate, concise, piecewise smooth surfaces from unorganized 3D points
tipically acquired by a 3D scanner.
Our research is motivated by numerous applications: reverse engineering,
design, inspection, planning of medical treatment, custom fitting,
textured objects, populating virtual worlds, display objects on internet
and special effect for films. About this latter we remember that Computer
Graphics is increasingly used in films. Special effects that would be
otherwise impossible, infeasible, or just expensive can be digitally
combined with video sequences. The extra character, objects, or background
tend to look more realistic if they are scanned from real counterparts
than if they were completely generated by a computer.
It is possible to develop algorithm for surface reconstruction without
having actual range scanner. So in literature we find a lot of proposal
starting by sampling points from a variety of existing surface models and
this was useful to compare results with known references.
Recently we have bought a touch-probe 3D scanner (see figures) and we have
realized that the most difficult problem is not to reconstruct a surface from
a set of 3D points, but to obtain a valid set of 3D points from a set of
range images and that this activity is strictly scanner type dependent.
In the following figure we show a Budda which is acquired with our scanner
in four step o range images, than these are merge and filtered to obtain
a first set of 3D valid points; note that the different point colours
mean they are taken from different range images.
About the surface reconstruction methods we are exploring both traditional
NURBS fitting tecniques and more powerful Subdivision and Radial Basis Function
surfaces interpolating and approximating.
In the following web site you can view some models that were scanned and recostructed
during our research project.
Some reconstructed models
G.Casciola, Ricostruzione di Superfici con Subdivison e Wavelets,
Special Projects GNCS, state of the work, Workshop GNCS, ex GNIM, Bertinoro
december 11-13, (2000).