A facial animation model needs either empirical data to feed the model directly or data which the model uses as the basis for a calculation. A texture map of skin and facial features is an example of the former; a model of the skull and attached muscles is an example of the later.
This short survey is concerned with the methods and apparatus used to gather the data for all such models. Some of these are used to drive animations of other parts of the body as well.
We divide the discussion into gathering photographic or videographic information, range and position finding, and medical imaging techniques that provide information about bones or muscle. In a few cases manufactures specifications are cited. This is not meant to be an endorsement of a specific product. Rather, it is intended to give the reader an idea of the state of currently available equipment.
The ideal system for gathering facial information would have the following characteristics: