B.  Sujatha, T.  Santhanam, 
    A Novel Approach Integrating Geometric and Gabor Wavelet Approaches to Improvise Visual Lipreading,
    International Journal of Soft Computing,
    Volume 5,Issue 1,
    2010,
    Pages 13-18,
    ISSN 1816-9503,
    ijscomp.2010.13.18,
    (https://makhillpublications.co/view-article.php?doi=ijscomp.2010.13.18)
    Abstract: Lipreading a perception of speech for listeners with hearing impairment is purely based on observing the lip movements under noisy conditions where visual speech information plays an important role. Lipreading, a visual modality which involves watching the movement of lips constitutes 1/3 of the conveyed message. This study investigates the use of two feature extraction methodologies for recognizing isolated words. The first type is based on a geometric approach which extracts the features like inner height, inner width, outer height and outer width of the lips while the second type is based on a set of Block-Based Gabor-Wavelet co-efficient extracted from each frame. Then these two features are given as input into the Ergodic Hidden Markov Model for recognizing the words.
    Keywords: Lip reading;visual feature extraction;lip segmentation;Gabor Wavelet Transform model;Height-Width model;Ergodic Hidden Markov model