Performance of Image Registration and Its Extensions for Interpolation of Facial Motion

We compare the performance of an intensity based nonparametric image registration algorithm and extensions applied to frame interpolation of mouth images. The mouth exhibits large deformations due to different shapes, additionally some facial features occlude others, e.g. the lips cover the teeth. The closures and disclosures represent a challenging problem, which cannot be solved by the traditional image registration algorithms.

The tested extensions include local regularizer weight adaptation, incorporation of landmarks, self-occlusion handling and penalization of folds, which have all been examined with different weight parameters.

Since the performance of these algorithms and extensions turns out to be superior in case of mouth closures, we provide an algorithm for the automatic selection of deformable template and static reference image for the registration procedure. Subjective tests show that the quality of results for interpolation of mouth images is enhanced by this proposal.