How to know that playbin2 can't play video format?

[Tim-Philipp Müller]

On Wed, 2013-05-08 at 20:32 -0400, Jim Norton wrote:
> Greetings,
> 
> I have a small GTK gstreamer application based on tutorials and sample  
> code that works using playbin2. However, if I set the playbin2 uri to  
> a file that contains a video and audio stream in which a gstreamer  
> plugin exists only to play the audio I end up with an empty video  
> window that displays no video while the sound is playing. How do I  
> detect at runtime in C code that a either the audio or video portion  
> of a stream is unable to be played?

You shouldn't end up with a video window if there's no suitable video
decoder (not one created by GStreamer anyway).

Does this also happen with gst-launch-0.10 ?

Cheers
 -Tim