title: How to extract just the audio from an MP4 file and convert it to FLAC file in C#?
body: <p>My goal is to write C# that turns Microsoft LYNC meeting audio into text.
  <a href="https://www.dropbox.com/s/lsopm8izs7j36ej/WaveConverter.zip?dl=0" rel="nofollow noreferrer">Here</a> is my project so far. Initially I was trying to record from microphone, save it to WAV then convert WAV to FLAC and using GoogleSpeechAPI, convert FLAC to text. But I got stuck recording microphone audio to WAV format. </p>
  
  <p>The problem is it needs to be in a very specific WAV format, i.e. int16 or int24 for the WAV to work with the WAV to FLAC convertion method. I kept recording 8 bits per sample instead of (16 or 24 bits) per sample. </p>
  
  <p>So, starting over. Microsoft Lync directly records meetings and saves it as a video in MP4 format. If I can somehow write code to convert MP4 to FLAC, that would also solve my problem. Any code example?</p>