This paper describes a new algorithm for recovering the
3D shape and motion of deformable and articulated objects
purely from uncalibrated 2D image measurements using an
iterative factorization approach. Most solutions to nonrigid
and articulated structure from motion require metric
constraints to be enforced on the motion matrix to solve
for the transformation that upgrades the solution to metric
space. While in the case of rigid structure the metric
upgrade step is simple since the motion constraints are linear,
deformability in the shape introduces non-linearities.
In this paper we propose an alternating least-squares approach
associated with a globally optimal projection step
onto the manifold of metric constraints. An important advantage
of this new algorithm is its ability to handle missing
data which becomes crucial when dealing with real video
sequences with self-occlusions. We show successful results
of our algorithms on synthetic and real sequences of both
de...
Alessio Del Bue, João M. F. Xavier, Lourdes