Skip to main navigation
Skip to Content
Computer Science
University of Toronto
U of T Portal
Student Support
Contact
About
Why Study CS at U of T
Career Options
History of DCS
Giving to DCS
Computer Science at UofT Mississauga
Computer Science at UofT Scarborough
Contact
Employment Opportunities for Faculty/Lecturers
How to Find Us
Undergraduate
Prospective Undergraduates
Current Undergraduates
Graduate
Prospective Graduate students
Current Graduate students
Research
Research Areas
Partner with us
People
Faculty
Staff
In Memoriam
Alumni and Friends
Honours & Awards
Women in Computer Science
Graduate Student Society
Undergraduate Student Union
Undergraduate Artificial Intelligence Group
Undergraduate Theory Group
News & Events
News
Events
@DCS Update
Alumni
Donate
You are viewing: >
Home
>
News & Events
>
Events
> AI: Machine Learning Seminar - August 1
About
Undergraduate
Graduate
Research
People
News & Events
AI: Machine Learning Seminar - August 1
Event date: Monday, August 01, 2011, at 11:10 AM
Location: PT 290C
Title: Two Topics in MAP-MRF Inference
Speaker: Vladimir Kolmogorov, University College London
Abstract:
Algorithms for MAP-MRF inference (computing maximum a posteriori configuration in a Markov Random Field) are of fundamental importance for many computer vision problems. I will talk about two such algorithms.
The first one, TRW-S, is a message passing technique for general MRFs with unary and pairwise terms, which is a variation of the tree-reweighted message algorithm by Wainwright et al.. Unlike Wainwright's techniques, TRW-S has certain convergence guarantees, and also performs better in practice.
Then I will consider the problem of computing correspondences between sparse image features related by an unknown non-rigid transformation and corrupted by clutter and occlusions. We formulate it as an instance of the graph matching optimisation problem, which is NP-hard in general. To tackle it, we use the dual decomposition approach with a particular choice of subproblems. Our method was able to find the global minimum within a minute in the majority of our examples. (These examples involved about 1000 potential correspondences.) This part of the talk is a joint work with L. Torresani and C. Rother.