2D Active Appearance Models (AAM) and 3D Morphable
Models (3DMM) are widely used techniques. AAM
provide a fast fitting process, but may represent unwanted
3D transformations unless strictly constrained not to do so.
The reverse is true for 3DMM. The two approaches also require
of a pre-alignment of their 2D or 3D shapes before
the modeling can be carried out which may lead to errors.
Furthermore, current models are insufficient to represent
nonlinear shape and texture variations. In this paper, we
derive a new approach that can model nonlinear changes in
examples without the need of a pre-alignment step. In addition,
we show how the proposed approach carries the above
mentioned advantages of AAM and 3DMM. To achieve this
goal, we take advantage of the inherent properties of complex
spherical distributions, which provide invariance to
translation, scale and rotation. To reduce the complexity
of parameter estimation we take advantage of a recent result
that shows how to...
Onur C. Hamsici, Aleix M. Martinez