Apply FFT on recording signal

Hi,
since the ios 4 we can take advantage of the accelerate framework which holds the vDSP API and this has a FFT in it. I want to use that for the microphone input and filter low tones with a low pass filter. can somebody explain me how to apply the FFT to my microphone input and then deal with the data from the FFT or does somebody has a link for me explaining that?
would really appreciate that, thx.
palmdale

I dont think I more info about this. Try googling yor way around or try looking into the free books apple has provided for developers. You might find something in these books.
http://www.tuaw.com/2010/12/19/apple-posts-free-developer-documentation-for-iboo ks-users/

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