Hi , You do not need to create a separate thread while working on Qt. AFAIK the <a href="http://www.gstreamer.net/data/doc/gstreamer/head/manual/html/chapter-helloworld.html">gst helloworld </a>has a g_main_loop so that the main thread does not exit while gstreamer runs in its own thread. But we don't have this problem while working with Qt GUI apps. I have attached a simple gst-launch style Qt gui app using gstreamer to demo this. Hope it saves time of someone :) <div class="gmail_quote"> On Fri, Apr 16, 2010 at 1:01 PM, 4ernov <<a href="mailto:4ernov@gmail.com">4ernov@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"> Hi, I try to make whole gstreamer pipeline live in separate thread. I need it generally because I work with very slow v4l2 device driver and it takes considerable time for to change state of pipeline (init driver etc.). So I create special QThread in Qt4 app and make all the construction work (i.e. create all the elements, the pipeline itself etc.) in its run() method. I also connect to the bus of the pipeline to get some info: GstBus* bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline)); gst_bus_add_watch (bus, audio_bus_call, this); gst_object_unref (bus); But I eventually found that all the message dispatching is processed in the main thread of the app. I.e. if I call thread() function which returns a pointer to a running thread in bus callback: void audio_bus_call() { qDebug()<<"thread:"<<thread(); } it returns a pointer to the main thread in spite of that all the GStreamer objects are created in different thread. Is there any way to make message dispatching process run in different thread other than main? Or somehow bind GStreamer event loop to Qt's event loop of some QThread object? Thank you very much, Alexey Chernov <div class="im"> ------------------------------------------------------------------------------ Download Intel&#174; Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. <a href="http://p.sf.net/sfu/intel-sw-dev" target="_blank">http://p.sf.net/sfu/intel-sw-dev</a> _______________________________________________ </div><div><div></div><div class="h5">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> </div></div></blockquote></div>