This item is available under a Creative Commons License for non-commercial use only
Communication engineering and systems
Delay, echo, encoding scheme, and packet loss all influence perceived quality of conversational speech transmitted over packet networks. Therefore, the choice of a buffer algorithm cannot be solely based on statistical loss/delay trade-off metrics. Also subjective “listening tests” or the newer ITU-T PESQ method, which don’t consider the effect of mouth-to-ear delay are inappropriate. We proposed a method for assessing VoIP call quality by extending the ITU-T E-model concept. This method provides a direct link to perceived conversational speech quality by estimating user satisfaction from the combined effect of information loss, delay and echo.
Narbutt, M. & Davis, M. (2005) Assessing the quality of VoIP transmission affected by playout buffer scheme. 4th international Conference on Measurement of Speech and Audio Quality in Networks (MESAQIN 2005), Prague, Czech Republic. 9-10 June 2005.