title: How to set-up WebRTC with VP9 codec and lossless compression
body: <p>I have been trying to figure out whether or not it is possible to set up WebRTC with VP9 codec and lossless compression.</p>
  <p>So far, I have been able to figure out, how to set VP9 in the SDP and also how to set the <a href="https://www.webmproject.org/vp9/profiles/" rel="nofollow noreferrer">coding profile</a> (0-3). However, my understanding is, that setting the encoder profile to index 3, does not have an impact on the compression.</p>
  <p>I also looked at the <a href="https://datatracker.ietf.org/doc/html/draft-ietf-payload-vp9-09" rel="nofollow noreferrer">RTP payload specification for VP9</a>. However, the <a href="https://datatracker.ietf.org/doc/html/draft-ietf-payload-vp9-09#page-19" rel="nofollow noreferrer">specification for the SDP parameters</a> only show how to set the codec and the coding profile.</p>
  <p>So my question is, is it at all possible to set up WebRTC with VP9 lossless compression? If so, where could I set it and does it have to be set in the SDP at all?</p>