Gstreamer Hyperloop

So I've been trying to get Gstreamer and Qt to play nice with each other on Cubieboard, but so far, no go.

Distinct attempts so far have been as follows:

1. Hacking QtMultimedia to specifically invoke the working vdpausink pipeline
1. this seems to be handled by  qtmultimedia/src/plugins/gstreamer/mediaplayer/qgstreamerplayersession.cpp on the Qt5 sources, on the VM host.
2. Setting the default playbin2 pipeline on GStreamer to use the vdpau elements, with GST_RANK_PRIMARY + 1
1. this seems to be handled by gst-plugins-bad-0.10.23/sys/vdpau/gstvdpau.c in the embedded rootfs (check the previous Gstreamer + libvpau-sunxi post)

Scenario #1 got me all the way to invoking VDPAU to a black screen from Qt and scenario #2 won't go all the way even from gst-launch on account of qtdemux:

playsink gstplaysink.c:2922:is_raw_pad:<playsink0:video_sink> Caps contains raw and non-raw structures:

video/x-vdpau-video, chroma-type=(int)0, width=(int)[ 1, 4096 ], height=(int)[ 1, 4096 ];
video/x-raw-yuv, format=(fourcc)I420, width=(int)[ 1, 4096 ], height=(int)[ 1, 4096 ];
video/x-raw-yuv, format=(fourcc)YV12, width=(int)[ 1, 4096 ], height=(int)[ 1, 4096 ];
video/x-raw-yuv, format=(fourcc)NV12, width=(int)[ 1, 4096 ], height=(int)[ 1, 4096 ]

A third possibility is to go with qtgstreamer, an alternative to QtMultimedia - still working that angle as well!