<html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body> <tt>Hi everyone, I am currently helping implement redistribution of live feeds from RTC streams that are coming out of janus-gateway. A user can share both its webcam, screen and audio and i end up with 2 pipelines to handle the re-encoding/merging and sending to a rtmp server. Janus is configured to forward everyting on RTC so i just use those as source. The webcam feed is working just fine, no big delay and the stream is stable. Problem arise with the screen feed and i can't really figure out why. It can take several minutes for the stream to display anything and when it does, i have lots of warnings and the stream is not in sync. It gets desync more and more as time goes by. The gstreamer is the same for the webcam and screen but only the screen have this behavior. This is the command for video only, there's also a command combining 2 RTP with rtpbin but the same problem occurs. gst-launch-1.0 udpsrc name=udpsrcvideo port=10055 caps=application/x-rtp,media=video,encoding-name=VP8,clock-rate=90000,payload=96 ! \ rtpjitterbuffer ! rtpvp8depay ! avdec_vp8 ! queue ! videoconvert ! x264enc tune=zerolatency speed-preset=faster bitrate=1000 ! \ flvmux streamable=true latency=1000000000 ! rtmpsink location=<a class="moz-txt-link-freetext" href="rtmp://">rtmp://</a>... I attach a level 4 log. What most confuses me is the warnings that appears after the pipe is set PLAYING. Really can't find much information about it. Since i have no problem with the webcam stream i fear it is a problem with the screen stream which i don't have much control over. Notable errors : x264enc :0::<x264enc0> non-strictly-monotonic PTS libav gstavviddec.c:1864:gst_ffmpegviddec_handle_frame:<avdec_vp8-0> Failed to send data for decoding rtpjitterbuffer rtpjitterbuffer.c:573:calculate_skew: delta - skew: 0:00:01.033519437 too big, reset skew rtpjitterbuffer rtpjitterbuffer.c:749:rtp_jitter_buffer_calculate_pts: backward timestamps at server, schedule resync rtpjitterbuffer rtpjitterbuffer.c:781:rtp_jitter_buffer_calculate_pts: resync to time 0:09:29.899406323, rtptime 0:09:38.611000000 x264enc :0::<x264enc0> VBV underflow (frame 1251, -349320 bits) videodecoder gstvideodecoder.c:2762:gst_video_decoder_prepare_finish_frame:<avdec_vp8-0> decreasing timestamp (0:17:59.517851383 < 0:18:00.273661763) I have messed around with buffers, latencies ... but i does not really improves anything. Thanks for the help! </tt><tt> </tt> </body> </html>