Evaluation of the effect of the GSM full rate codec on the automatic detection of laryngeal pathologies based on cepstral analysis

Advances in speech signal analysis during the last decade have allowed the development of automatic algorithms for a non-invasive detection of laryngeal pathologies. Bearing in mind the extension of these automatic methods to remote diagnosis scenarios, this paper analyzes the performance of a pathology detector based on Mel Frequency Cepstral Coefficients when the speech signal has undergone the distortion of a speech codec such as the GSM FR codec, which is used in one of the nowadays most widespread communications networks. It is shown that the overall performance of the automatic detection of pathologies is degraded less than 5 %, and that such degradation is not due to the codec itself, but to the bandwidth limitation needed at its input. These results indicate that the GSM system can be more adequate to implement remote voice assessment than the analogue telephone channel. Index Terms: speech analysis, speech coding, voice function assessment