public void record (string outputpath){
    pipeline                   = new Pipeline ("screencast-pipe");
    muxer                      = ElementFactory.make ("matroskamux", "mux");
    dynamic Element sink       = ElementFactory.make ("filesink", "sink");

    //video bin
    var videobin               = new Gst.Bin ("videobin");
    dynamic Element vsrc       = ElementFactory.make ("ximagesrc", "vsrc");
    dynamic Element colorspace = ElementFactory.make ("ffmpegcolorspace", "color");
    dynamic Element vencode    = ElementFactory.make ("diracenc", "vencode");
    videobin.add_many  (vsrc, colorspace, vencode);
    videobin.link_many (vsrc, colorspace, vencode);

    //audio bin
    var audiobin               = new Gst.Bin ("audiobin");
    dynamic Element asrc       = ElementFactory.make ("autoaudiosrc", "asrc");
    dynamic Element aconv      = ElementFactory.make ("audioconvert", "aconv");
    dynamic Element aresample  = ElementFactory.make ("audioresample", "aresample");
    dynamic Element audiorate  = ElementFactory.make ("audiorate", "arate");
    dynamic Element aencode    = ElementFactory.make ("vorbisenc", "aencode");
    audiobin.add_many  (asrc, aconv, aresample, audiorate, aencode);
    audiobin.link_many (asrc, aconv, aresample, audiorate, aencode);

    //configure
    sink.set ("location", outputpath);

    if (pipeline==null||muxer==null||sink==null||videobin==null||vsrc==null||colorspace==null||
        vencode==null||audiobin==null||asrc==null||aconv==null||aresample==null||audiorate==null||
        aencode==null){
        stderr.printf ("Error: Elements weren't made correctly!\n");
    }

    pipeline.add_many (videobin, muxer, sink);//audiobin
    //videobin.get_static_pad ("src_%d").link(mux.get_request_pad ("video_%d"));
    videobin.add_pad (new GhostPad ("src", muxer.get_request_pad ("video_%d")));
    audiobin.add_pad (new GhostPad ("src", muxer.get_request_pad ("audio_%d")));
    muxer.link (sink);

    pipeline.get_bus ().add_watch (bus_message_cb);
    pipeline.set_state (State.PLAYING);
    Timeout.add (500, (GLib.SourceFunc) update_slide);
}

private bool bus_message_cb (Gst.Bus bus, Message msg){
    switch (msg.type){
        case Gst.MessageType.ERROR:
            GLib.Error err; string debug;
            msg.parse_error (out err, out debug);
            print ("Error: %s\n", err.message);
            pipeline.set_state (State.NULL);
            break;
        case Gst.MessageType.EOS:
            print ("Finished, why??\n");
            pipeline.set_state (State.NULL);
            break;
        case Gst.MessageType.STATE_CHANGED:
            Gst.State oldstate; Gst.State newstate; Gst.State pending;
            msg.parse_state_changed (out oldstate, out newstate, out pending);
            print ("state changed: %s->%s:%s\n", oldstate.to_string (), newstate.to_string (), pending.to_string ());
            break;
        default:
            break;
    }
    return true;
}

private void pad_added_cb (Pad pad){
    var sinkpad = muxer.get_request_pad ("video_%d");
    if (sinkpad == null){
        Caps caps = pad.get_caps_reffed ();
        Signal.emit_by_name (muxer, "request-pad", caps, out sinkpad);
    }
    if (sinkpad == null){
        stderr.printf ("Couldn't get an encoding channel for pad ...\n");
    }
    var pad_link_ok = (pad.link (sinkpad) == PadLinkReturn.OK);
    if (!pad_link_ok) {
        warning ("Failed to link pad '%s' to '%s'", pad.name, sinkpad.name);
    }
    return;
}