title: Audio equalizer using FFmpeg
body: <p>I'm developing audio player using FFmpeg.  I want to add audio equaliqer to my app, but I don't know how to do it. I know that FFmpeg has a FFT functions, but I have count of samples that not mutch with any power of 2. I also tried to use other FFT libraries, but I have some noise on my audio after equalization.
  Can anybody help me to understand how to use FFmpeg's FFT functions or any oter ways to implement audio-eq using FFmpeg?</p>