VASC Seminar Announcement
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Date: Monday, 5/7/01
Time: 4:00-5:00
Place: NSH 3002

Speaker: Steve Seitz, U. Washington
Title:   Seeing 3D:  The Space of All Stereo Images

A stereo pair consists of two images with purely horizontal parallax,
that is, every scene point visible in one image projects to a point
in the same row of the other.  While stereo pairs are typically formed
from perspective cameras, recent research has identified interesting
new stereo varieties, including so-called "stereo panoramas" that
enable an observer to maintain a depth perception for a 360 degree
field of view.  In light of these results, a natural question is:
what is the space of all stereo pairs?  In particular, suppose that
you could construct two sensors, each of which can capture any 2D set
of light rays and place the resulting measurements in an image.  What
is the range of light rays and sensor designs that produce a stereo
pair?

In this talk I will present a theory of stereo image formation that
enables a complete classification of all possible stereo pairs,
including non-perspective varieties.  Towards this end, the notion
of epipolar geometry is extended to apply to multiperspective images,
and it is shown that only three varieties of epipolar surfaces exist.
Based on this analysis it is shown that any stereo pair must consist
of rays lying on quadric surfaces.  A unified representation is developed
to model all classes of stereo views, based on the concept of a quadric view.
The benefits include a unified treatment of projection and triangulation
operations for all stereo views.

The framework is applied to derive three new types of stereo image
representations with unusual and useful properties.