There are two components to research on this problem,
mathematical formulation of the shape-comparison problem
and the computational solution method. We have
a clear, well-defined
formulation and polynomial-time algorithms for solution.
Previous
research has involved either ill-defined formulations
or heuristic
methods for solution.
Our starting-point for the implementation is the
edit-distance algorithm of Klein et al. We discuss
how we
altered that algorithm to handle rotation-invariance
while keeping
down the time and storage requirements. Most important,
we define
costs for the edit-operations and give an algorithm for
computing them.
We use a database of shapes to illustrate that our approach
performs
intuitively in categorization and indexing tasks, and
our results are
better than previous approaches.
@inproceedings{Klein:etal:SODA2001,
author = {Philip Klein and Thomas Sebastian and Benjamin Kimia},
title = {Shape matching using edit-distance: an implementation},
booktitle = {Twelfth Annual ACM-SIAM Symposium on Discrete Algorithms (SODA)},
address = {Washington, D.C.},
month = {January 7-9},
pages = {781--790},
year = {2001},
}
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