Video sink stuttering (xv/gl/auto)

[Zeno Endemann]

On 19.08.21 20:23 Nicolas Dufresne wrote:
> Not certain. I see some stuttering, but it's a side effect of clock drift
> between display (at 60hz) and render 30hz. At 60hz, it looks better. Note that
> this pipeline is all sw driven.

Yes, running at 60fps I still think I can occasionally see a hickup, but 
it is much better. SW driven should not really matter, as it handles 
60fps better than 30fps, so this is not about performance, but rather 
somehow bad timings of the output plugins. Of course in general 30fps is 
not that smooth overall, especially in such a synthetic stream, but I am 
specifically talking about irregular stuttering on top of that.

I can't imagine clock drift being so bad that this is as noticeable as 
this. With displaying every frame two times you should get perfect 
playback on a 60fps display. Ok, clock drift between the rtc and display 
vsync can happen, but it simply can't be this bad. And as I said, 
playback of the 30fps video file doesn't show that problem either, or at 
least it is much less noticeable.

I suppose I'll report this as a bug...

Anyway, thanks for the feedback

-- 
Zeno Endemann | zeno.endemann at kdab.com | Software Engineer
KDAB (Deutschland) GmbH, a KDAB Group company
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