ISSN : 1796-2048
Volume : 1    Issue : 6    Date : September 2006

Automatic Recognition of Facial Actions in Spontaneous Expressionss
Marian Stewart Bartlett, Gwen C. Littlewort, Mark G. Frank, Claudia Lainscsek, Ian R. Fasel and
Javier R. Movellan
Page(s): 22-35
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Spontaneous facial expressions differ from posed expressions in both which muscles are moved,
and in the dynamics of the movement. Advances in the field of automatic facial expression
measurement will require development and assessment on spontaneous behavior. Here we
present preliminary results on a task of facial action detection in spontaneous facial expressions.
We employ a user independent fully automatic system for real time recognition of facial actions from
the Facial Action Coding System (FACS). The system automatically detects frontal faces in the video
stream and coded each frame with respect to 20 Action units. The approach applies machine
learning methods such as support vector machines and AdaBoost, to texture-based image
representations. The output margin for the learned classifiers predicts action unit intensity.
Frame-by-frame intensity measurements will enable investigations into facial expression dynamics
which were previously intractable by human coding.

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