title: Compile ffmpeg with AMR decoding
body: <p>I'm trying to compile ffmpeg for Android to convert amr files to wav. So I ran:</p>
  
  <p><code>./configure --help |grep arm</code> </p>
  
  <p>and I'm getting:</p>
  
  <p><code>--enable-libopencore-amrnb enable AMR-NB de/encoding via libopencore-amrnb [no]
    --enable-libopencore-amrwb enable AMR-WB decoding via libopencore-amrwb [no]
    --enable-libvo-amrwbenc  enable AMR-WB encoding via libvo-amrwbenc [no]</code></p>
  
  <p>So for decoding amr I think I should use --enable-libopencore-amrwb in my configure script, right? But when I add it to my configure script, I get: </p>
  
  <pre><code>ERROR: libopencore_amrwb not found
  </code></pre>
  
  <p>What should I do? Should I download opencore-amr library and put source code anywhere? Or there is other way to get amr decoding in ffmpeg?</p>