February 12, Tuesday
12:00 – 13:00
New Distance Functions and Learning with General Distance Functions
Computer Science seminar
Lecturer : Ofir Pele
Affiliation : Department of Computer and Information Science, University of Pennsylvania
Location : 202/37
Host : Dr. Aryeh Kontorovich
Histogram distance functions are the cornerstone of numerous computer vision
and machine learning tasks (e.g. image retrieval, descriptor matching and
k-nearest neighbor classification). It is common practice to use distances
such as the Euclidean and Manhattan norms to compare histograms. This
practice assumes that the histogram domains are aligned. However, this
assumption is violated through quantization, shape deformation, light
changes, etc. The Earth Mover’s Distance (EMD) is a cross-bin distance that
addresses this alignment problem. We present several new Earth Mover's
Distance variants that are robust to outlier noise and global deformations.
Additionally, we present efficient algorithms for their computation. We show
state-of-the-art results for descriptor matching and image retrieval. These
tools have already been used by other groups and demonstrated
state-of-the-art results for a range of tasks such as superpixel matching,
descriptor matching, image retargeting, image segmentation, social graph
comparisons and population density comparison. Finally, we describe several
future directions including learning with general (not necessarily
positive-semidefinite) similarity functions.