If it helps to anyone, I solved the negotiation problem with inserting another videoconvert in front of capsfilter: appsrc->rtpjitterbuffer->rtpvp8depay->vp8dec0->videomixer->*videoconvert->*capsfilter->videoconvert->vp8enc->webmux -- Sent from: http://gstreamer-devel.966125.n4.nabble.com/