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Colloquia

Matching images: rigidity and co-saliency

Kostas Daniilidis
University of Pennsylvania

September 27, 2007
Troy Building room 2018 - 4:00 p.m. to 5:00 p.m.
Refreshments at 3:30 p.m.

Abstract:

We address the problem of matching two pictures of a scene taken from two separate viewpoints, with potentially large non-overlapping parts. In the first part of the talk we only assume rigidity of the scene while in the second part we match co-salient regions. We formulate the problem as a search problem in the cartesian product of all possible correspondences. In this space, candidate matches vote for geometry hypotheses with a vote weight depending on local image similarity. The voting process can be written as a Radon transform and we present a new scheme for computing it efficiently based on Fourier analysis on the sphere and the rotation group. We show that the maximum of the Radon transform is a very good global similarity metric for images and apply it in the organization of unordered sets of pictures. We relax the geometry constraint and instead we ask for matching of regions which match and are salient in both images. We maximize a score function that segments jointly two images and matches their spectral embeddings. Soft segmentations from two images are aligned through rotation in the embedding space and the resulting global matching score is affected only from salient matched regions.

Bio:

Kostas Daniilidis is Associate Professor of Computer and Information Science at the University of Pennsylvania where he was Assistant Professor from 1998 to 2003. He is a member of the interdisciplinary GRASP laboratory. He obtained his undergraduate degree in Electrical Engineering from the National Technical University of Athens, 1986, and his PhD (Dr.rer.nat.) in Computer Science from the University of Karlsruhe, 1992, under the supervision of Hans-Hellmut Nagel. His research interests are in space and motion perception with machines, with applications on navigation, multi-view reconstruction, omnidirectional vision and immersive environments. He has been Associate Editor of IEEE Transactions on Pattern Analysis and Machine Intelligence. In 2000, he founded the series of IEEE Workshops on Omnidirectional Vision. He was Area Chair of the ECCV 2004, CVPR 2004, 2005, and 2006, and ICCV 2007 conferences. In June 2006, he chaired with Mark Pollefeys the Third Symposium on 3D Data Processing, Visualization, and Transmission.

Hosted by: Volkan Isler (x3275)

Last updated: August 26, 2007