Flows for Shape Up:Shape
Shock Graphs and Shape Matching
We have been developing a theory for the generic representation of 2-D
shape, where structural descriptions are derived from the shocks (singularities)
of a curve evolution process, acting on bounding contours. We have now
begun to apply the theory to the problem of shape matching. The shocks
are organized into a directed, acyclic shock graph, and complexity
is managed by attending to the most significant (central) shape components
first. The space of all such graphs is highly structured and can be characterized
by the rules of a shock graph grammar. The grammar permits the reduction
of a shock graph to a unique rooted shock tree. We have introduced a novel
tree matching algorithm which finds the best set of corresponding nodes
between two shock trees in polynomial time. Using a diverse database of
shapes, we have demonstrated our system's performance under articulation,
occlusion, and moderate changes in viewpoint. Representative results are
shown in Fig. 5.4.
K. Siddiqi, A. Shokoufandeh (Rutgers University), S. J. Dickinson
(Rutgers University), S. W. Zucker (Yale University) [
Figure 5.4: Similarity between database shapes and class prototypes.
In each row, a box is drawn around the most similar shape.
Mon Jun 26 21:22:20 GMT 2000