Investigations on viseme groups in Welsh

The general viseme groups of the Welsh language are found to be very similar to those found in other European languages. Of the consonants found only in the Welsh language the uvular fricative /x/ was grouped with velar and glottal consonants. Generally / / forms an individual viseme group and is quite distinct from /1/, and /1/ was found to be indistinguishable from /r/. Maternal language of the subjects affected the response rates of /r/ and /r/ and the identification rate of / /. The statistical technique of cluster analysis provided an objective method of viseme grouping, and it is discussed as an aid to speechreading training.