title: Recording each channel using ALSA API
body: <p>I'm using a playstation eye, plugged into a raspberry pi. I have the raspberry pi recognising the built in microphone array of the PSEye and I can sample input levels using </p>
  
  <pre><code>arecord -vv /dev/null -r 16000 -f S16_LE -c 4 -D iec958:CARD=CameraB409241,DEV=0 /dev/null &lt; /dev/null
  </code></pre>
  
  <p>Now obviously this shows the levels for all 4 channels being summed together. What I wish to do is record each channel separately. Is this possible using the ALSA API?</p>
  
  <p>I've looked through this <a href="http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html" rel="nofollow">http://www.alsa-project.org/alsa-doc/alsa-lib/pcm.html</a></p>
  
  <p>And took a look at this <a href="http://www.linuxjournal.com/article/6735?page=0,2" rel="nofollow">http://www.linuxjournal.com/article/6735?page=0,2</a></p>
  
  <p>But neither seemed to what I needed. This is also similar to sampling both channels of a stereo mic over ALSA as well I suppose. Eventually I want to be able to sample the dB from each microphone at a specific point in time.</p>