title: using ffmpeg to convert gif to mp4 , output doesn't play on android
body: <p>I just use the following command to convert a gif file to mp4 but the resulting mp4 file doesn't play in android default video player .<br>
  what did I wrong ?<br>
  is there any aditional steps should I take to produce android playable mp4 files ?</p>
  
  <pre><code>$ ffmpeg -f gif -i infile.gif outfile.mp4
  </code></pre>
  
  <p>my test gif file : <a href="http://www.wired.com/wp-content/uploads/images_blogs/design/2013/09/tumblr_inline_mjx5ioXh8l1qz4rgp.gif" rel="noreferrer">Test Gif File</a><br>
  My desktop played the output.mp4 very well using VLC Media Player and also MX Player on my android device played the video file without any error.</p>