Influencing playbin2/decodebin2 auto-plugging

[Tvrtko Ursulin]

On Monday 06 August 2012 16:18:19 Tvrtko Ursulin wrote:
> On Monday 06 August 2012 16:12:23 Tim-Philipp Müller wrote:
> > Hi,
> > 
> > > I am seeing a weird interaction between using autoplug-select and vaapi.
> > > The attached reproducer does not transition into playing state for me
> > > unless I remove the line where I connect my message handler to
> > > autoplug-select. Interesting thing is that my handler in this
> > > configuration does not deviate from the default behaviour ie. it always
> > > returns GST_AUTOPLUG_SELECT_TRY.
> > > 
> > > In the no VA-API setup, with use_vaapi set to False at the top of the
> > > program, playback works fine even with the autoplug-select handler
> > > installed.
> > > 
> > > Seems weird, any ideas?
> > 
> > I think playbin2 hooks up some of these signals as well
> > ("autoplug-factories", "autoplug-select", "autoplug-continue"), so the
> > default for playbin2 would be whatever playbin2 does there.
> 
> What? :) Sorry but I don't understand what you wrote. What do you think is
> broken/interacting badly and why?

I see now that when my autoplug-select handler is installed, playbin2's one is 
not called at all. And it actually looks like a non-trivial code there. 

Solvable? I really liked this approach.. if this is a dead end I will have to 
attempt your other suggestion of iterating over the plugin registry and modify 
ranks. Hopefully it is doable from Python. 

Do you perhaps have any pointers (examples) to start me up there?

Thanks,

Tvrtko