Héctor Delgado, Massimiliano Todisco, Md Sahidullah, Achintya K. Sarkar, Nicholas Evans, Tomi Kinnunen and Zheng-Hua Tan
Research Report RR-16-322, Accepted to the IEEE Workshop on Spoken Language Technology (SLT), December 13-16, 2016, San Juan, Puerto Rico
Abstract: Many authentication applications involving automatic speaker verification (ASV) demand robust performance using short-duration, fixed or prompted text utterances. Text constraints not only reduce the phone-mismatch between enrolment and test utterances, which generally leads to improved performance, but also provide an ancillary level of security. This can take the form of explicit utterance verification (UV). An integrated UV + ASV system should then verify access attempts which contain not just the expected speaker, but also the expected text content. This paper presents such a system and introduces new features which are used for both UV and ASV tasks. Based upon multi-resolution, spectro-temporal analysis and when fused with more traditional parameterisations, the new features not only generally outperform Mel-frequency cepstral coefficients, but also are shown to be complementary when fusing systems at score level. Finally, the joint operation of UV and ASV greatly decreases false acceptances for unmatched text trials.