Hi, Ok I did what you recommended: add a videoscale between ffmpegcolorspace and ximagesink. I did not get error this time, but the pipeline was blocked I think. So as usual, I thought the problem was about synchronisation. I tried several possibilities and I finally found one that works: gst-launch-0.10 rtspsrc location="rtsp://<a href="http://mafreebox.freebox.fr/freeboxtv/201" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">mafreebox.freebox.fr/freeboxtv/201</a>" ! rtpmp2tdepay ! flutsdemux name=d d. ! mpeg2dec ! queue ! ffmpegcolorspace ! videoscale ! ximagesink d. ! mad ! queue ! alsasink So thx for the idea of "videoscale". Do you know why this element is needed ? I will now try to experiment the netsim element from farsight plugin. Any advise about this element would be appreciated. Sincerely Julien I. <div>2008/4/9, Zaheer Merali <<a href="mailto:zaheermerali@gmail.com">zaheermerali@gmail.com</a>>:<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> On Tue, Apr 8, 2008 at 11:29 PM, Julien Isorce <<a href="mailto:julien.isorce@gmail.com">julien.isorce@gmail.com</a>> wrote: > Hi, > > The following pipeline works fine:(sound + video) > gst-launch-0.10 playbin uri="rtsp://<a href="http://mafreebox.freebox.fr/freeboxtv/201">mafreebox.freebox.fr/freeboxtv/201</a>" > > > I tried with -v option to have informations of the pipeline made then I > tried: > > gst-launch-0.10 rtspsrc location="rtsp://<a href="http://mafreebox.freebox.fr/freeboxtv/201">mafreebox.freebox.fr/freeboxtv/201</a>" > ! rtpmp2tdepay ! flutsdemux name=d d. ! queue ! mpeg2dec ! ffmpegcolorspace > ! ximagesink d. ! mad ! alsasink > Try adding a videoscale between ffmpegcolorspace and ximagesink. Zaheer > but it is not working, log : > > " > ERREUR: de l'élément /pipeline0/rtspsrc0/udpsrc0 : Erreur de données de flux > interne. > ... >  streaming task paused, reason not-negociated (-4) > ... > "" > > Where am I wrong in the command line ? > > > Then I want to use the netsim element from farsight plugin. Do I have to > insert it between rtspsrc and rtpmp2tdepay ? > > Thx > > > > ------------------------------------------------------------------------- >  This SF.net email is sponsored by the 2008 JavaOne(SM) Conference >  Register now and save $200. Hurry, offer ends at 11:59 p.m., >  Monday, April 7! Use priority code J8TLD2. > > <a href="http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone">http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone</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">https://lists.sourceforge.net/lists/listinfo/gstreamer-devel</a> > > </blockquote></div>