How does playbin automatically chose video-sink?

[Gary Thomas]

I have a situation which uses playbin "under the covers", i.e.
I'm using gst-play-1.0 on a video stream which uses playbin but
does not [currently] support an option to pass video-sink.

I'd like to understand how playbin is choosing the video sink
because the automatic selection only works for a complete
screen overlay (X11) but is failing when the output should
be a specific window.  I've found that playbin chooses GstOverlaySink
(that's what the .dot file says).  I believe I could get this
working better if I could select a more appropriate sink for
my hardware.

Questions:
* How is this selection made?
* What might be the best way to mange the automatic selection
   so that my [more appropriate] sink is chosen?

Thanks for any insight

n.b. it should be obvious that I'm interested in gstreamer-1.0
solutions.

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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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