Periodic jerkyness

Personally I am stuck at 60hz with my LCD so I cannot run at 50hz, 48hz, or 24hz. As far as I know I need a 3:2 pulldown to properly display these frame rates.

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miljbee Wrote:I am on WinXP SP3 and i Experience the same problem :
When i am watching a 24fps movie with refresh rate @ 60hz, it's super smooth during something like 10-15s, then it's jerky for 2-5s. The jerk seems really regular. I have no problem when i watch the same movie at 24Hz.
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drivesoslow :
Yes, in the world of perfection, you need pulldown, but playing 24fps movies at 60Hz should look smooth. This situation means that XBMC has got 2,5 chances to display a frame at nearly the good timestamp (60/24 = 2,5).
It should be smooth.

The only thing that i can see that could affect all those video players is the way vBlank is called (raised ?).

I Don't know how it works, but I Think that on a multithreaded platform, it's hard to catch this event without consuming all the cpu power to wait for vBlank.

One of the big causes of this recurring stutter is when the time to present a frame according to the dvdplayer is close to the vsync time. When this occurs, the frame can with bad luck end up on different sides of that vsync every few frames or so. This skipping back and forth will cause alot of stuttering.

This could explain those periods of stuttering, (ie longer than a single frame missed).

It's quite hard to know when a vsync interval exactly is timing wise, and with a hardware clock that keeps jumping back and forth wich it can do on multicore systems it's even harder.

Thanks for the info!
Is this remotely fixable by the way?

[Ad0];282475 Wrote:Thanks for the info!
Is this remotely fixable by the way?

Did you find a fix for this problem? I have the same issue on my Sony Bravia W4500..

Turning on the setting to sync clock to video instead of audio, can reduce the problem. But it only works properly with non passthrough audio.

jochr Wrote:Did you find a fix for this problem? I have the same issue on my Sony Bravia W4500..

What fixed the problem was the smoothvideo branch that got merged back to main a while back. Thanks to bob1on1 !