video4linux2 device detection

[Erick Pérez Castellanos]

On Mon, 2012-02-20 at 08:09 -0800,
gstreamer-devel-request at lists.freedesktop.org wrote:
> You can use the (rather horrible) GstPropertyProbe interface for that,
> on the "device" property. The source element may need to be set to
> READY
> state for that to work.
> 
> Cheers 
> -Tim 

Thxs Tim, I'll try that one, I tried to test those properties before but
I think I was missing the state of the pipeline to READY.
I'll try it.
Thxs