Recognition of facial expressions - Knowledge Based Systems ...

Figure 19. System functionality
The initial design idea specified the working of the system as for regular conditions. In
order to have the system working in a common environment on video capturing, it was
required to have a reliable module for feature detection from the input video signal.
Because such a module was not available (a feature extraction module existed, but had
poor detection rate) at the moment of developing the system, a minor change was made.
A new module for extracting the visual features from the images was built. It relied on
the infra red effect on the pupils as for primarily detecting the location of the eyes. As
soon as the data related to the eye location was available, the system could use it as
constraints in the process of detecting the other visual features. The feature detection
module represents the first processing component applied on the input video signal. The
data provided by that module are used for determining the probabilities of the each
emotional class to be associated with the individual’s current face.
The architecture of the system includes two software applications. One application is
assumed to manage the task of data capturing from the video camera. It acts like a clientside
application in a network environment. The second application has the goal of
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