thanks for your reply, it works now. gst-launch udpsrc port=54962 caps="application/x-rtp,media=video,clock-rate=90000,encoding-name=H264,profile-level-id=428032,sprop-parameter-sets=\"Z0KAMukGCcg\=,aM48gA\=\=\",payload=96" ! rtph264depay ! decodebin2 ! ffmpegcolorspace ! autovideosink -v <div class="gmail_quote">2010/5/18 Wim Taymans <<a href="mailto:wim.taymans@gmail.com">wim.taymans@gmail.com</a>> <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> <div><div></div><div class="h5">On Tue, 2010-05-18 at 15:22 +0800, 孝恆呂 wrote: > hi, all, > > I wrote a simple RTSP client to contact an existing RTSP IP CAM, > > and take a conversation to the CAM: > > >> OPTIONS * RTSP/1.0 > >> CSeq: 30 > >   << RTSP/1.0 200 OK >   << CSeq: 30 >   << Public: DESCRIBE,SETUP,PLAY,OPTIONS,PAUSE,TEARDOWN > > >> DESCRIBE rtsp://myipcam/h264.sdp RTSP/1.0 > >> CSeq: 31 > >   << RTSP/1.0 200 OK >   << CSeq: 31 >   << Cache-Control: no-cache >   << Content-Length: 171 >   << Content-Type: application/sdp >   << x-Accept-Retransmit: our-retransmit >   << x-Accept-Dynamic-Rate: 1 > >   << v=0 >   << m=video 0 RTP/AVP 96 >   << a=rtpmap:96 H264/90000 >   << a=control:trackID=1 >   << a=fmtp:96 > packetization-mode=1;profile-level-id=428032;sprop-parameter-sets=Z0KAMukGCcg=,aM48gA== > > >> SETUP rtsp://myipcam/h264.sdp/trackID=1 RTSP/1.0 > >> CSeq: 32 > >> Transport: RTP/AVP;unicast;client_port=54962-54963 > >   << RTSP/1.0 200 OK >   << CSeq: 32 >   << Cache-Control: no-cache >   << Session: 135514808124572 >   << Transport: > RTP/AVP;unicast;client_port=-10574--10573;server_port=6970-6971 > > >> PLAY rtsp://myipcam/h264.sdp RTSP/1.0 > >> CSeq: 33 > >> Session: 135514808124572 > >> Range: npt=0.000- > >   << RTSP/1.0 200 OK >   << CSeq: 33 >   << Session: 135514808124572 >   << Range: npt=now- > > it works and now the RTSP IP CAM continuously streams packets to my > local port number (#54962) > > but for some purpose I didn't create an UDP listener on port #54962, > > instead, I want to use gstreamer to playback the incoming video > stream, > > the below is my command: > >   gst-launch -v udpsrc port=54962 caps="application/x-rtp, > media=video, clock-rate=90000, encoding-name=H264" ! rtph264depay ! > decodebin2 ! ffmpegcolorspace ! autovideosink > </div></div>You forgot to pass the fmtp parameters to the depayloader on the caps. In particular, the depayloader does not have sprop-parameter-sets which contains SPS and PPS for the decoder. Wim <div class="im"> > it works to receive the incoming packets, > > but error occurs at the decoding stage, > > ... > ... > 0:00:53.466058000  4272   019F78E8 ERROR                 ffmpeg .:0:: > decode_slice_header error > 0:00:53.468058000  4272   019F78E8 ERROR                 ffmpeg .:0:: > no frame! > 0:00:53.677070000  4272   019F78E8 ERROR                 ffmpeg .:0:: > non-existing PPS referenced > 0:00:53.680071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > non-existing PPS 0 referenced > 0:00:53.682071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > decode_slice_header error > 0:00:53.683071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > no frame! > 0:00:53.685071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > non-existing PPS referenced > 0:00:53.687071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > non-existing PPS 0 referenced > 0:00:53.689071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > decode_slice_header error > 0:00:53.691071000  4272   019F78E8 ERROR                 ffmpeg .:0:: > no frame! > ... > ... > > can anyone helps?? > > > > -- > Hsiao-heng Lu </div>> ------------------------------------------------------------------------------ > > _______________________________________________ > gstreamer-devel mailing list > <a href="mailto:gstreamer-devel@lists.sourceforge.net">gstreamer-devel@lists.sourceforge.net</a> > <a href="https://lists.sourceforge.net/lists/listinfo/gstreamer-devel" target="_blank">https://lists.sourceforge.net/lists/listinfo/gstreamer-devel</a> ------------------------------------------------------------------------------ _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.sourceforge.net">gstreamer-devel@lists.sourceforge.net</a> <a href="https://lists.sourceforge.net/lists/listinfo/gstreamer-devel" target="_blank">https://lists.sourceforge.net/lists/listinfo/gstreamer-devel</a> </blockquote></div> -- Hsiao-heng Lu