  Lip reading is used to understand or interpret speech without hearing it, a
technique especially mastered by people with hearing difficulties. The ability
to lip read enables a person with a hearing impairment to communicate with
others and to engage in social activities, which otherwise would be difficult.
Recent advances in the fields of computer vision, pattern recognition, and
signal processing has led to a growing interest in automating this challenging
task of lip reading. Indeed, automating the human ability to lip read, a
process referred to as visual speech recognition, could open the door for other
novel applications. This thesis investigates various issues faced by an
automated lip-reading system and proposes a novel "visual words" based approach
to automatic lip reading. The proposed approach includes a novel automatic face
localisation scheme and a lip localisation method.
