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I was hoping the new beta 2 would fix the problem, but its still evident.
The issue being that the video does not play at an even rate, there is a very slight jitter in the video. It would mostly noticeable during pans for most people. However, the TV I have my HTPC hooked up to is one of those newfangled 120hz sets that can interpolate the image to look super smooth. It only works properly for movies when the output is a clean 24fps - a single dropped or delayed frame here or there screws it up.
When playing the same videos in Vista Media Center, Mediaportal or Media Player (DVDs, .mkvs, .wmvs, etc), they play back in sync, and the 120hz interpolation will lock in. Any video in XBMC is a no go for that. I've tried just about every setting imaginable that might have an effect on it and it seems like its just an internal issue.
To be clear, these arent frames being dropped. Pressing O to bring up the stats will not show dropped frames, and the CPU usage is no higher than 40%, even on HD videos. The a/v quickly fluctuates between 0.000 and 0.040 or so.
Setup:
Intel Pentium Dual Core 2.0ghz
Nvidia 8400 GS
2gb RAM
Vista Home Basic
Any ideas?
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There already has been a similar thread on this, but maybe now is the time to tackle the problem. The effect is most apparent as said before on horizontal pans, but also visible during vertical ones and scrolling credits.
If this should turn out to be a video card problem, I'm on ATI.
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I've installed XBMC on two very diferent PC's, both brand new Dual Core Intel and AMD specs (around 3Ghz). I have been tweaking and trying different things since Alpha 3 but it's identical on both PC's. When I watch horisontal pans in 720p (my TV doesn't support 1080p) it jitters just slightly like "mdaria510" mention. The infamous Planet Earth: Bird scene plays fine without any stutter. There might be things I haven't tried, but it's not that big a deal. I have the feeling it's something that will go away as XBMC matures over the next months and the internal codecs like ffdshow gets some more revisions..
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WiSo
Team-Kodi Developer
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Did you first notice the jitter with beta2 or also earlier?
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Same problem for me. Small stuttering when camera is panning on my 42" LCD.
XBMC have always given me this problem. (plays fine with MPC, MP and more).
E6400 3GHz dualcore
GForce 8600GT
2Gb Ram
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tslayer
Team-XBMC Developer
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Gotcha, but without a way for devs to reproduce, it is hard for us to help.
My videos all play perfectly.
42.7% of all statistics are made up on the spot
Always read the XBMC online-manual, FAQ and search the forum before posting.
Do not e-mail XBMC-Team members directly asking for support. Read/follow the forum rules.
For troubleshooting and bug reporting please make sure you read this first.
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Understandable, as it might not be plainly obvious in most cases. But on my tv, it's night and day because I can plainly see whether or not the 3:2 cadence is there for the interpolation to lock on. There might be little I can do coding-wise to help, but my setup can be a perfectly objective test for any fixes/changes regarding the issue.
I'm curious...is this an officially recognized issue by the xbmc devs, or is it really a matter of "we can't reproduce it, so there's no issue"?
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2008-10-07, 18:20
(This post was last modified: 2008-10-07, 18:24 by midgetspy.)
My XBMC has always done this as long as I've had my HTPC. It's extremely difficult to notice except on specific panning scenes, though, and I bet the vast majority of people have never noticed (and when people say "my XBMC works fine" they just can't tell). It's done this on 3 totally different hardware setups and 2 OSes.
The only place I usually notice it is in nature shows like Planet Earth. Recently I noticed it in a single scene in Cars. If you pay attention to a single edge during a pan you will notice that it is not moving smoothly but is slightly jerky. It never stops moving, but it just slows down and speeds up slightly as it pans. I always assumed it was just another XBMC <-> ffmpeg issue, but maybe if it has to do with fps/Hz it'll be simpler than that to fix?
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yeah, that's my guess as well...that it's so subtle for most people that they might not b aware there's an issue.