hi, all. I'm trying the rtp plugin refer to the doc at: <a href="http://webcvs.freedesktop.org/gstreamer/gst-plugins-good/gst/rtp/README?revision=1.13&view=markup">http://webcvs.freedesktop.org/gstreamer/gst-plugins-good/gst/rtp/README?revision=1.13&view=markup</a> Here's my simple pipeline: gst-launch -v filesrc location=shake.mp4 ! qtdemux name=d \ d. ! { queue ! rtpmp4vpay ! udpsink port=5000 } \ d. ! { queue ! rtpmp4gpay ! udpsink port=5002 } but after it's run, here is the output: Setting pipeline to PAUSED ... /pipeline0/queue0.sink: caps = video/mpeg, mpegversion=(int)4, systemstream=(boolean)false, codec_data=(buffer)000001b001000001b58913000001000000012000c48d88007d0a041e1463000001b24c61766335312e34302e34, width=(int)320, height=(int)240, framerate=(fraction)15/1 /pipeline0/queue0.src: caps = video/mpeg, mpegversion=(int)4, systemstream=(boolean)false, codec_data=(buffer)000001b001000001b58913000001000000012000c48d88007d0a041e1463000001b24c61766335312e34302e34, width=(int)320, height=(int)240, framerate=(fraction)15/1 /pipeline0/rtpmp4vpay0.src: caps = application/x-rtp, media=(string)video, payload=(int)96, clock-rate=(int)90000, encoding-name=(string)MP4V-ES, ssrc=(guint)3831296950, clock-base=(guint)4106776350, seqnum-base=(guint)53267, profile-level-id=(string)1, config=(string)000001b001000001b58913000001000000012000c48d88007d0a041e1463000001b24c61766335312e34302e34 /pipeline0/rtpmp4vpay0.sink: caps = video/mpeg, mpegversion=(int)4, systemstream=(boolean)false, codec_data=(buffer)000001b001000001b58913000001000000012000c48d88007d0a041e1463000001b24c61766335312e34302e34, width=(int)320, height=(int)240, framerate=(fraction)15/1 /pipeline0/queue1.sink: caps = audio/mpeg, mpegversion=(int)4, framed=(boolean)true, codec_data=(buffer)1290, rate=(int)32000, channels=(int)2 /pipeline0/queue1.src: caps = audio/mpeg, mpegversion=(int)4, framed=(boolean)true, codec_data=(buffer)1290, rate=(int)32000, channels=(int)2 /pipeline0/rtpmp4gpay0.src: caps = application/x-rtp, media=(string)audio, payload=(int)96, clock-rate=(int)32000, encoding-name=(string)MPEG4-GENERIC, ssrc=(guint)3458294825, clock-base=(guint)2594580451, seqnum-base=(guint)42905, encoding-params=(string)2, streamtype=(string)5, profile-level-id=(string)2, mode=(string)AAC-hbr, config=(string)1290, sizelength=(string)13, indexlength=(string)3, indexdeltalength=(string)3 /pipeline0/rtpmp4gpay0.sink: caps = audio/mpeg, mpegversion=(int)4, framed=(boolean)true, codec_data=(buffer)1290, rate=(int)32000, channels=(int)2 /pipeline0/udpsink1.sink: caps = application/x-rtp, media=(string)audio, payload=(int)96, clock-rate=(int)32000, encoding-name=(string)MPEG4-GENERIC, ssrc=(guint)3458294825, clock-base=(guint)2594580451, seqnum-base=(guint)42905, encoding-params=(string)2, streamtype=(string)5, profile-level-id=(string)2, mode=(string)AAC-hbr, config=(string)1290, sizelength=(string)13, indexlength=(string)3, indexdeltalength=(string)3 /pipeline0/udpsink0.sink: caps = application/x-rtp, media=(string)video, payload=(int)96, clock-rate=(int)90000, encoding-name=(string)MP4V-ES, ssrc=(guint)3831296950, clock-base=(guint)4106776350, seqnum-base=(guint)53267, profile-level-id=(string)1, config=(string)000001b001000001b58913000001000000012000c48d88007d0a041e1463000001b24c61766335312e34302e34 Pipeline is PREROLLING ... Pipeline is PREROLLED ... Setting pipeline to PLAYING ... New clock: GstSystemClock According to the doc, there should be udpsink0 and udpsink1, but I only have one udpsink in the output. Is there anything wrong with my pipeline? I'm fairly new with gstreamer. Can anyone hlep me? Thanks very much.