Visual Activity Context For Focus of Attention Estimation in Dynamic Meetings
Sileye Ba, Hayley Hung and Jean-Marc Odobez
In: IEEE Proc. Int. Conf. on Multimedia and Expo (ICME), New-York, US(2009).
We address the problem of recognizing, in dynamic meetings in
which people do not remain seated all the time, the visual focus of
attention (VFOA) of seated people from their head pose and contextual
activity cues. We propose a model that comprises the VFOA of
a meeting participant as the hidden state, and his head pose as the
observation. To account for the presence of moving visual targets
due to the dynamic nature of the meeting, the locations of the visual
targets are used as an input variables to the head pose observation
model. Contextual information is introduced in the VFOA dynamics
through a slide activity variable and speaking or visual activity
variables that relate people’s focus to the meeting activity context.
The main novelty of this paper is the introduction of visual activity
context for FOA recognition to account for the correlation between
a person’s focus and the other people’s gestures, hand and body motions.
We evaluate our model on a large dataset of 5 hours. Our
results show that, for VFOA estimation in meetings, visual activity
contextual information can be as effective as speaking context.