title: Android MediaCodec & MediaExtractor For video and audio playing
body: <p>I'm new here and fresh to Android development. Here is my first question here.</p>
  
  <p>I'm using <code>MediaExtractor</code> and <code>MediaCodec</code> to play <code>mp4</code> file, with video and audio. Now I get one pair of extractor/codec for video and another pair of extractor/codec for audio, realized in two separate threads.</p>
  
  <p>My question is: can I use just one extractor with two codecs to play video and audio synchronously?</p>
  
  <p>If yes, How to do it? When I used extractor.selecttrack for one, the other won't work... </p>
  
  <p>Thanks a lot.</p>
  
  <p>Thanks to everyone's answer here. I have figure this out. I made a mistake that the extractor can only select one track. Actually, you can select more than one track, and extractor.advance() will read each track at one time subsequently.</p>