
Chapter | 5 Image and Video Processing Tools for HCI
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Global model detection: More robust techniques for detection and
tracking can be constructed using deformable 2D or 3D face mod-
els. The face model constrains the solutions to be valid examples of
the object modelled. The first works in this direction [27] only used
the model for tracking purposes, and the initialisation of the facial
features was done manually. The model was defined as a nonuni-
form mesh of polyhedral elements, and the search was conducted
with an extension of active contours (snakes). More recently, elas-
tic bunch graph matching (EBGM) [28] has been proposed as a
model-based