On Mar 26, 2007, at 9:21 AM, David Fleming wrote: > I'm working on an audio spectrum analyzer and it sure would be > nice to have QT do the FFT math. There may be a way to use QT with > live data (from the mic or audio input) by setting up a "movie" > audio track in memory, but I can't seem to figure out how to do it.
You can read QuickTime data from a mic/input, but you don't want to use a movie audio track for that. Instead, you should use the capture APIs in QuickTime, set everything up like you're going to do an audio recording, and then there is a flag you can set to make it not record. Instead, you catch all the incoming data in a QuickTime driven callback. Contact me offlist and I can try to help with a few more of the details. > I've been struggling to code the FFTs in RB and haven't had much > success. It's pretty complex stuff. I did find a FFT plugin for RB > this weekend. Hopefully that will work. I haven't tried realtime FFTs with REALbasic before, but I suspect it's feasible. There are probably several options here too. I suspect that you'll run into problems doing it with pure RB code (the realtime part is why). Frank mentioned FMOD. Also, Apple has FFT apis available. Or, maybe you could do the coding in pure REALbasic, but use Altivec operations to help with the math speed. Another interesting idea might be to pursue the ability to make a REALbasic application act as an AudioUnit host. Then, you have access to any AudioUnit plugin. _______________________________________________ Unsubscribe or switch delivery mode: <http://www.realsoftware.com/support/listmanager/> Search the archives: <http://support.realsoftware.com/listarchives/lists.html>
