title: How to extract semi-precise frequencies from a WAV file using Fourier Transforms
body: <p>Let us say that I have a WAV file. In this file, is a series of sine tones at precise 1 second intervals. I want to use the FFTW library to extract these tones in sequence. Is this particularly hard to do? How would I go about this?</p>
  
  <p>Also, what is the best way to write tones of this kind into a WAV file? I assume I would only need a simple audio library for the output.</p>
  
  <p>My language of choice is C</p>