  In this paper, we defined the viseme (visual speech element) and described
about the method of extracting visual feature vector. We defined the 10 visemes
based on vowel by analyzing of Korean utterance and proposed the method of
extracting the 20-dimensional visual feature vector, combination of static
features and dynamic features. Lastly, we took an experiment in recognizing
words based on 3-viseme HMM and evaluated the efficiency.
