Friday, 4 September 2009

Using recorded wavfiles as help information in CALL-SLT

I've got a new feature working on CALL-SLT, which allows speech input to be logged and reused as help for students. When you start the system, it asks whether or not you wish to be considered a native speaker. If you answer yes, it keeps the wavfile for each successful match, and stores it in such a way that that the wavfile is associated with the current prompt. Subsequently, if a student is given the same prompt and hits the HELP button, the native speaker's wavfile is replayed. By construction, we know that the native speaker was correctly recognized, so if the student can just imitate them well enough they should be recognized too.

The idea is simple, but there were some messy technical problems... a bad interaction between Nuance and SICStus concerning relative pathnames, and the question of what happens if two different users try to check in new wavfiles simultaneously. I think I have decent solutions, though. For more details, look at the online documentation which I have just added. This also tells you how to download and run the system.

No comments: