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[Linux] HOW-TO achieve perfect playback at 23.97 or 59.94 Hz with NVIDIA GPU hardware - Printable Version

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+--- Thread: [Linux] HOW-TO achieve perfect playback at 23.97 or 59.94 Hz with NVIDIA GPU hardware (/showthread.php?tid=70068)



- gokudo - 2010-11-01 23:50

I noticed that i can't playback material ripped straight from some hdtv stations of my country which are 720p@50fps NOT interlaced. Audio drops out in short periods and video stutters. I was able to play such material in 9.11 though but only when switching to 720p, now even that doesn't help anymore. Don't know what to do about that for the moment, it seems this mode just isn't covered correctly, "only" 23,97, 25(50 interlaced) and 29,97(59,94 interlaced) work so far. I would take a wild guess that real non-interlaced 60fps material may cause the same problems now.

EDIT: Works now, don't know why now since I changed nothing only switched around a bit again and again to the same settings that worked for me in 9.11. I get the feeling some options need to be set more time than once to really change. Well it's a beta after all. Sorry for the false alarm.


- sebj - 2010-11-06 02:55

Quote:I would take a wild guess that real non-interlaced 60fps material may cause the same problems now.

Actually, I'm struggling with this right now.

Would love to know what you did man Laugh


- thecapsaicinkid - 2010-11-10 13:27

I haven't read the entire thread so excuse me if this has been mentioned already.

xrandr 'lies' about available refresh rates and will report unique ids such as 50.0, 51.0, 52.0.. until you set the EnableDynamicTwinView=false in xorg.conf at which point it'll display the actual rates 50.0, 60.0, 75.0 etc. That would give you spurious results if you ran the 'check' command at the beginning of this guide before you changed your xorg.conf.

Secondly, and kind of related, beware that if you have gpu scaling enabled and a PAL tv, the nvidia driver may be scaling to a 50Hz mode (it seems to scale everything to the nvidia-auto-select mode) even if you have chosen 60Hz as your desired output. This will cause problems running 60fps videos (a problem I had for ages).


- Jyujinkai - 2010-11-10 16:19

i do not understand what this post is about... can someone explain it so i know if i need to do it?


- thecapsaicinkid - 2010-11-11 16:35

Jyujinkai Wrote:i do not understand what this post is about... can someone explain it so i know if i need to do it?
Most screens report that they capable of more than one 'variation' of a particular refresh rate, i.e 59.94/60Hz.

Your system can only support one instance of a particular rate so it'll have to choose one which may in some cases be the undesirable one. Using the example above, your system may choose exactly 60Hz for its 60Hz mode and not 59.94Hz which is preferable ('60Hz' videos are actually 59.94)


- boba23 - 2010-11-13 19:49

Hey guys,

thought I'd post here, to maybe find a solution to my current "problem".
Basically my playback seems fine, also 24p is ok.
I am running current svn-dharma build here. Since a few weeks, I am running into frame drop problems. No matter what content, 24p HD or 25/24hz SD content. I get constant frame drops like 5-10 per minute for no obvious reasons.
I can fix this by activating sync playback to display with video resampling activated. I never had to do this before and didn't have those frame drops.
I am running Ubuntu 10.10 64bit, latest nvidia drivers, xorg.conf is adjusted according to this howto, has been the same way before the frame drops started happening.
Any ideas?

boba


- X3lectric - 2010-11-13 20:56

sync to playback HAS to be selected, in order to use this thread info, not sure about re-sampling.

look at main post under 5. Adjusting the settings in XBMC.


also there's no such thing as the latest svn of anything...

As for why it worked before or now it doesn't its all a mystery due to each user individual setup, and error and lack of information posted.


- bobo1on1 - 2010-11-13 21:00

It might mean that the refreshrate is slightly too low, or the soundcard is playing slightly too fast, sync playback to display with resample can compensate for those speed differences.


- boba23 - 2010-11-13 23:45

X3lectric Wrote:sync to playback HAS to be selected, in order to use this thread info, not sure about re-sampling.

look at main post under 5. Adjusting the settings in XBMC.


also there's no such thing as the latest svn of anything...

As for why it worked before or now it doesn't its all a mystery due to each user individual setup, and error and lack of information posted.

I had the sync to playback option set to "audio" as mentioned in this howto. Worked perfectly fine as well. But it doesn't anymore. Gives me frame drops. Only thing that helps is setting it to "video (resample audio)". I simply would like to find out what causes this. Since it seems that I am the only one affected by this ;-) somehow ...

boba


- Th3R00st3r - 2010-11-16 19:44

boba23 Wrote:I had the sync to playback option set to "audio" as mentioned in this howto. Worked perfectly fine as well. But it doesn't anymore. Gives me frame drops. Only thing that helps is setting it to "video (resample audio)". I simply would like to find out what causes this. Since it seems that I am the only one affected by this ;-) somehow ...

boba

I am getting frame drops as well on my Revo 1600
I can play 1920x800 np, but 1920x1080 skips like every 4-5 frames.

Here is a screen shot of the video info. The VQ hovers at 98-99+%. I only hve 1GB ram in the box, would adding another 1GB sovle this issue. Probably wouldn't hurt..
[url=[Image: w91HW.png]][Image: w91HW.png][/url]