[MPlayer-dev-eng] [PATCH] reduce flashing on resize with VDPAU

[Reimar Döffinger]

On Mon, Mar 23, 2009 at 08:45:28AM -0700, Stephen Warren wrote:
> Dan Oscarsson wrote:
> > On 2009-03-18 at 10:34 +0100 Reimar Döffinger wrote:
> > > You can try attached patch. There are some issues though: I only
> > > tested with the blit engine, which behaves a bit weirdly, it
> > > should be possible to disable it, and it should be possible to
> > > adjust the number of output surfaces used.
> > > It might also be nicer to allow skipping in the draw_image part for
> > > cases where the GPU usage is the issue, but that has higher jitter.
> > 
> > I have now built on your patch by adding knowledge on the vsync
> > interval and vsync time so that it can better align display and
> > dropping to get best showing of frames.
> 
> The best way to handle this would be to use the VDPAU presentation queue's
> timestamp mechanism; choose a timestamp for each frame to be presented,
> give this to the presentation queue, then use the "displayed at" time
> returned by the presentation queue status commands to determine whether
> presentation is drifting to become late or not.

As I understood your last comment on this, this feature does still not
allow play videos with higher fps than the vsync rate, thus frames still
need to be dropped "manually" and to decided whether to do this or not
we still better estimate if a vsync will happen "soon" or not.

> > I can also identify when the blitting engine is used so that it can be
> > handled differently from the other one.
> 
> That's odd; the two mechanisms are designed to have the same semantics
> and be indistinguishable. If that's not the case, it's a bug we'd like
> to fix. Why do you feel the need to distinguish the two mechanisms, and
> how are you doing so?

Because the blit engine is not limited to the screen refresh (vsync)
rate, thus there is no (/not much) need to do frame dropping etc.
Assuming this hasn't changed, I have not tested the beta drivers, only
180.37...