The aim of this work is to learn a shape prior model
for an object class and to improve shape matching with the
learned shape prior. Given images of example instances,
we can learn a mean shape of the object class as well as
the variations of non-affine and affine transformations separately
based on the thin plate spline (TPS) parameterization.
Unlike previous methods, for learning, we represent
shapes by vector fields instead of features which makes our
learning approach general. During shape matching, we inject
the shape prior knowledge and make the matching result
consistent with the training examples. This is achieved
by an extension of the TPS-RPM algorithm which finds a
closed form solution for the TPS transformation coherent
with the learned transformations. We test our approach by
using it to learn shape prior models for all the five object
classes in the ETHZ Shape Classes. The results show that
the learning accuracy is better than previous work and the
learne...