Emotion recognition is performed by extracting a set comprising at least
one feature derived from a signal, and processing the set of extracted
feature(s) to detect an emotion therefrom. The voice signal is low pass
filtered prior to extracting therefrom at least one feature of the set.
The cut-off frequency for the low pass filtering is typically centered
around 250 Hz. The features are e.g. statistical quantities extracted
from sampling a signal of the intensity or pitch of the voice signal.