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AmirG
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Most of the content I have in HD is at 720p/24Hz (Babylon can't handle 1080p on my setup, hopefully Camelot will). However, my Philips LCD don't have a 720p/24Hz mode, only 720p/50Hz and 720p/60Hz, and as a result, every HD video I watch has this annoying tearing (or jitter or whatever it's called).
As far as I can tell, most TVs don't have a 720p/24Hz mode, so how do YOU watch such content? Do you upscale it to 1080p/24Hz? Do you use some pull-down to convert it to 720p/50Hz or 60Hz? Is there some other solution?
And whichever solution you employ, is it done by XBMC, the underlying OS, your AV receiver or perhaps your TV?
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I've currently limited my xorg modelines to 1920x1080/60hz and 1920x1080/24hz since my TV supports those. I'm then letting XBMC do the upscaling (via the nvidia card). This gives me 24hz playback even on DVD rips at 1080p/24.
My TV, like yours, only supports 24hz at the 1080p resolution so I have to let the player do the upscaling.
If you're getting tearing that shouldn't be from a refresh mismatch. That's probably a VSync issue. Refresh mismatch should only give you a 3:2 pulldown (frames repeated 3 times, then 2 times, then 3, etc.). Which gives slightly less smooth playback (however... that's how TV broadcasts shot in film work so you're used to it and probably won't notice it anyway).
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AmirG
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It only happen when the camera panes or when there's a cut, then I get a horizontal tear.
XBMC debug option reports that it's doing about 24 FPS while xorg log file reports that the TV is in 720p/60Hz. So the framerate doesn't match. Wouldn't that cause tearing or does XBMC (and I'm still using the Babylon stable release) or the TV do a pull down automatically?
I have vsync set as on everywhere, I have twinview disabled, I've added every suggested setting to my xorg.conf, theonly thing left I can think of is that refresh rate missmatch.
Comes Camelot with its supposed performance improvements with VPDAU and I'll be able to test that theory.
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That shouldn't cause tearing and pull down should be automatically applied. Is VSync turned on in XBMC as well? Also is Compiz disabled in X?
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AmirG
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Oh, sorry, I wasn't clear: the Menus are rendered at 30FPS, which fits as the TV is working at 60Hz. When a video is played, it's at about 24FPS while the TV is still at 60Hz, as is evident from the X log file.
The framerate the videos are supposed to be played in is 24, verified with Media Player Classic under Windows.
Thanks for the help, I'll try to update the driver and see how it goes.
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same things for me. The XBMC settings was 1920*1080/60Hz and my TV is 50Hz only.
On slow scrolling it was not smooth and i have set xbmc to 1920*1080/50Hz and it's very better but not perfect.
A friend had the same problem, and solves with starting ubunutu with XBMC session mode. He had desable the twinview etc....
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valexi
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Hi!
I have those latest NVIDIA drivers, and I am able to set my ubuntu to 1080p/24hz resolution, but it seems that XBMC oversets that resolution. I can't change this refresh rate to 1080p/24hz, from XBMC because it lovers the resolution, when going under 50hz.
Any clues? This is very weird, because my Popcorn hour player is able to do 24p standard, and it is linux based too...
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i have a optoma hd65 (seems like a popular budget projector) and it allows custom modelines for 23.976Hz and 48Hz at 1280*720. its very good.