September 22-25, 1997
The problem of how to prompt a client for a password in an automatic, prompted speaker verification system is addressed. Text-prompting of four-digit sequences is compared to speech-prompting of the same sequences, and speech-prompting of four digits is compared to speech-prompting of five digits. Speech recordings are analyzed by comparing speaker verification performance and by inspecting the number and type of speaking errors that subjects made. From the experiment it is clear that text-prompting gives the subjects an easier task and fewer speaking errors are produced in that context. When enrolling clients with text-prompted speech and performing verification with an HMM-based system, the average EER was larger for speech-prompted items compared to text-prompted items, but changes in individual EERs varies across the test population.
Bibliographic reference. Lindberg, Johan / Melin, Håkan (1997): "Text-prompted versus sound-prompted passwords in speaker verification systems", In EUROSPEECH-1997, 851-854.