frequency value extraction from audio signal

Hi guys,

I am working on a project in which I'm trying to translate a live audio signal
into corresponding streaming midi data. I have managed to work out a
reasonable way of extracting a velocity value from the amplitude of the signal
however am stuck on extracting the frequency value - necessary to translate it
into a midi pitch. I have looked into FFT but it seems very difficult if not
impossible to isolate a single frequency value in hz from the signal, and even
more difficult doing so with it streaming in real-time. I'm not too fussed if
there's a slight delay in pitch change between the live signal and the midi
signal (seems it may be more possible to do on small chunks of recorded audio
data - analysed and the value extracted, rather than a continuosly streaming
signal), however it would be nice if I could find a way to do it in real-time.
Anyone have any ideas? I plan to use the 'ftom' object to convert the frequency
value into its corresponding midi pitch, however all I need is a way of
actually getting the frequency value out of the signal in a single changing
number.

Any help or ideas, even alternative ways of working around this would be much
appreciated.

Cheers,

Ryan