Are there any open source libraries for performing FFTs on the iPhone?

I would like to compare to WAV audio files using an FFT. What open source libraries and / or sample code exis开发者_运维问答t for performing such an operation?

Apple's aurioTouch sample app (available on the developer.apple.com web site) includes source code for an FFT (not as fast as the one in the iOS4 Accelerate framework though). The sample app also contains a source code example of how to use an FFT to process audio input data, which is very similar to the raw PCM data contained in a .wav file after the header.

Accelerate.framework