Temporal segmentation of real time video is an important
part for automatic facial expression recognition system.
Many studies for facial expression recognition have
been carried out under restricted experimental environment
such as pre-segmented video set. In this paper, we present
a real-time temporal video segmenting approach for automatic
facial expression recognition applicable in a smartphone.
The proposed system uses a Finite State Machine
(FSM) for segmenting real time video into temporal phases
from neutral expression to the peak of an expression. The
FSM uses Lucas-Kanade’s optical flow vector based scores
for state transitions to adapt the varying speeds of facial expressions.
While even HMM based or hybrid HMM model
based approaches handling time series data require sampling
times, the proposed system runs without any sampling
time delay. The proposed system performs facial expression
recognition with Support Vector Machines (SVM) on every
apex state after automatic temporal segmentation. The mobile
app with our approach runs on Samsung Galaxy S3
with 3.7 fps and the accuracy of real-time mobile emotion
recognition is about 70.6% for 6 basic emotions by 5 subjects
who are not professional actors.