title: Count frames in H.264 bitstream
body: <p>How to count/detect frames (pictures) in raw H.264 bitstream? I know there are 5 VCL NALU types but I don't know how to rec(k)ognize sequence of them as access unit. I suppose detect a frame means detect an access unit as access unit is</p>
  
  <blockquote>
    <p>A set of NAL units that are consecutive in decoding order and contain
    exactly one primary coded picture. In addition to the primary coded
    picture, an access unit may also contain one or more redundant coded
    pictures, one auxiliary coded picture, or other NAL units not
    containing slices or slice data partitions of a coded picture. The
    decoding of an access unit always results in a decoded picture.</p>
  </blockquote>
  
  <p>I want it to know what is the FPS of live stream out to server.</p>