Tel-Aviv University - Computer Science Colloquium
Sunday, April 2, 14:15-15:15
at 14:00
Schreiber Building, Room 309
Static, Dynamic and Transparent
Structure From Motion
Shai Avidan
Microsoft Research
Abstract:
The problem of structure-from-motion (SFM) has been extensively explored.
Yet, most of the work seems to focus on the case of a camera moving
in a
static, Lambertian 3D environment. Clearly, our world is much more
complicated than that and pushing the envelope of SFM algorithms is
needed.
In this talk I will review some of the progress done in three complementing
areas of SFM. First, I will present a new method for recovering the
ego-motion of a camera moving in a static 3D world. This method takes
advantage of the relationships between affine and perspective projections
and is especially suited for dealing with video sequences. Then, I
will
present a new method that can recover the 3D coordinates of moving
objects
seen from a single moving camera. This problem can only be solved if
some
constrains on the motion of the objects is placed. I coin the term
"trajectory triangulation" to describe this family of tasks and, in
particular, I focus on the case of objects that move along a straight
line
or along a conic section. Finally, I will present a new approach to
handle
reflections in 3D scenes. At its core, the new approach offers a new
method
for decomposing reflections, seen by a moving camera, into the individual
layers that created them. Taken together, these contributions extend
the
capabilities of SFM algorithms.
Parts of this work were done with P. Anandan, Amnon Shashua and Rick
Szeliski.
For colloquium schedule, see
http://www.math.tau.ac.il/~zwick/colloq.html