Evaluation of the G.729 speech coder with pathological voice samples

The performance of a speech coder is typically evaluated with a battery of objective and subjective tests. Objective measures of speech quality attempt to measure the "distance" between the original and coder-processed speech, while subjective testing involves obtaining mean opinion score (MOS) for the coder-processed speech. In general these tests are performed with speech samples collected from normal talkers, and no tests are conducted to determine how a speech coder interacts with abnormal speech samples. This paper focuses on the performance of the ITU standardized G.729 speech coder with speech and voice samples from disordered talkers. Standardized objective measures of speech coder quality and acoustic measures of voice are used to show that there is a significant drop in the performance of the G.729 speech coder when abnormal speech samples were used.