IOS: recording sound below a certain frequency

Question

I am working on an application in which I have to record from an iPhone microphone, but my requirement is to record only voice below a certain frequency. All other voices greater than this frequency should not be recorded.

I know that SO already has a lot of posts about this, but I have not found anything useful.

I find the frequency using this code: - http://www.ehow.com/how_12224909_detect-blow-mic-xcode.html

But I am having problems to avoid recording this frequency.

Can someone suggest me how to do this, or if any lib / open source is available. Any help on this would be appreciated.

Thanks in advance.

Answer 1

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