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Since upgrading to 0.1.6, 24 fps material on my Pioneer Kuro set to 23.976 hz is a complete chop fest. It seems to be stuttering along nearly 80% of the time. Is anyone else experiencing this? Switching to 60hz alleviates this issue, but of course introduces back the 3:2 judder.
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elan
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Well, I was hoping to have made things better in that department, but apparently not. Things are definitely more accurate now, in terms of the refresh rates that are reported back to the player. Not sure why it's introducing problems (and only sometimes). Please discuss and see if you guys can figure out a common theme.
-elan
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Elan, since I don't have any other displays to test with, I am curious if it is a display-specific issue. Does 0.1.6 at 24hz work on your Bravia? On my pioneer I am getting consistent frame drops at 24hz, but nearly none at 60hz. 0.1.5 worked well with 24hz, with only the occasional hickup.
Also, are you using a custom SwitchResX display mode, or the built in setting from Display Preferences?
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elupus
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elan, what did the GetMaximumFPS return before? to large or too small? If it was too large, then reducing it could only increase the number of frames dropped, it wouldn't reduce it.
If this is happening on sd clips, then adding a output cache wouldn't help at all.
Could somebody test a clip that drops frames in 60 hz and check what speed xbmc is playing it at? if it's playing at 24 fps, then it is going drop one frame every 41 frames ( 1/ (24 - 23.976) ) if you have a display that is 23.976.
That is a quite noticable frame drop.
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elupus,
When I watch the playback speed, it varies and is always a moving target. It ranges from 22 to 24.5. Occasionally, it hits lows as 14fps however, this still doesn't not effect the dropped frames. At 60hz my 2.33 C2D mini seems to be fine with 1080p content, until i change to 24hz and a slideshow ensues with 0.1.6
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elupus
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DeanM3 so you are saying fps keeps fluctuation alot on even SD material? If it is then that is probably the reason of the framedrops when set to 24. The issue with "24hz" is that player can never catch-up without dropping frames. Thus is it ever lags behind it have to drop frames even if cpu can decoder way quicker than standard fps.
Could you guys check for continuously logged "Discontinuties" in log when playing with display at anything higer than 24hz on the same clips that fail on 24hz. If you get that then audio renderer isn't accurate enough and playback clock will jump around alot.
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Here are the results of my tests:
Using 0.1.6 at both 1080p 60hz and 24hz with Vertical sync off, I am dropping 0 frames.
The frame rate monitor fluctuates between 23.95, 23.98, 23.99 and 24.0
If I turn on vertical sync, at 60hz I get a judder in frame rate every 10 seconds or so, and at 24hz the picture is extremely choppy with continuous dropped frames.
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Just tried it on my 0.1.6 install (UK D3000 Bravia which can accept 1080p/24)
1080p/24 gives smooth 24fps mkv playback. However there is a sound sync issue (varies up to around 0.5sec)
Playing an SD encoded xvid (both PAL and NTSC) gives jerky playback. However I found one where playback was fine - no idea why.
Everything plays find when I switch back (either to a native 1360x768 or 1080p/60).
If I turn off vsync, then I get what I believe is called tearing (i.e. horizontal break-up) however the jerkyness for SD is removed (well, as unjerky as it can be)
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elan
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Playing PAL/NTSC videos in 24Hz mode (or anything < 50/60Hz) is known to be problematic.
-elan
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