link demux

[Tim-Philipp Müller]

On Wed, 2013-06-26 at 20:52 +0200, "Simon Krütt" wrote:

Hi,

> can someone help me please to link my demuxer to another element.
> so far I tried to link the pads like this:
>  
>  gst_bin_add_many (GST_BIN (pipeline), videosrc, demux, queue,
> videoenc, rtppayload,
>        NULL);
>   sinkpad = gst_element_get_request_pad ( queue, "queue_sink");
>   srcpad = gst_element_get_static_pad (demux, "src");
>   if (gst_pad_link (srcpad, sinkpad) != GST_PAD_LINK_OK)
>     g_error ("Failed to link video queue to demux");
>   gst_object_unref (srcpad);
>  
>  
> and I'm getting this error:
>  
> (mp4test:32152): GStreamer-CRITICAL **: gst_pad_link_full: assertion
> `GST_IS_PAD (srcpad)' failed
> ** (mp4test:32152): ERROR **: Failed to link video queue to demux
> Trace/breakpoint trap (core dumped)

It would be nice if you told us what demuxer this is exactly!

I think you need to read up on 'dynamic pads' - most demuxers have
dynamic source pads which will only be created once data flow has
started:

http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-pads.html#section-pads

Cheers
 -Tim