title: Retrieving timestamp in RTP/RTSP
body: <p>I am using libav/ffmpeg for connecting to IP cameras. I do need to extract the absolute timestamp from the frames, not pts/dts. How can I have this value?</p>
  
  <p>Using Wireshark I can see the following response from the camera (Axis P1355):</p>
  
  <p>RTP-Info: url=rtsp://xxx.dyndns.org:4378/axis-media/media.amp/trackID=1?fps=4&amp;resolution=1280x720&amp;compression=60;seq=32446;rtptime=3287715479\r\n</p>