[Colloquium] Reminder: TTI-C Show and Tell Series: McAllester (TOMORROW @ 12:00 pm)

[Katherine Cumming]

TTI-C SHOW AND TELL SERIES

Presented by:  Toyota Technological Institute at Chicago
 

Speaker: David McAllester, TTI-C
Speaker's home page:  http://ttic.uchicago.edu/~dmcallester/


Time: Tuesday, February 14, 2006
Location: TTI-C Conference Room
Lunch Provided @ 12:00pm 
Seminar @ 12:15pm

 
Title:

A Min-Cover Approach to Finding Multiple Curves in an Image

Abstract:

Object detection is a widely studies problem of computer vision.  Here we
consider the problem of simultaneously detecting many objects.  Of course,
multiple objects can be detected by using repeated single object detection.
More specifically, one finds a first object, removes that object form the
image, then finds a second object and so on.  Here we develop an alternative
to repeated single object detection based on optimizing a statistical
objective function defined over a space of ``scenes'' where each scene
simultaneously identifies multiple objects.  The optimization problem we
consider is an instance of the general min-cover problem.  This problem is
NP-hard in general but polynomial time approximation algorithms exist.  We
apply this general framework to the problem of finding curves in an image
and give empirical results on the Berkeley segmentation data set.

Here we focus on the problem of identifying multiple curves in an image.
Intuitively, a curve is a path in the image corresponding to a single
underlying cause.  For example, a curve can be caused by an occlusion (a
discontinuity in depth), a sharp change in albedo (paint on a sign), a sharp
change in lighting (a shadow), or a sharp change in orientation (the corner
of a building).  An image typically contains a large number of curves.  We
are interested in the problem of finding the curves in an image where,
intuitively, each curves has a single cause and each cause is represented by
a very small number of curves --- ideally just one curve per cause. 

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If you have questions, or would like to meet the speaker, please contact
Katherine at 773-834-1994 or kcumming at tti-c.org.   For information on future
TTI-C talks and events, please go to the TTI-C Events page:
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60637)