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

This xorg.conf has worked on all systems TV I have tried:
http://xbmclogs.com/show.php?id=4386

DFP-0 might be changed to DFP-1

(2012-07-08 10:31)FernetMenta Wrote:  This xorg.conf has worked on all systems TV I have tried:
http://xbmclogs.com/show.php?id=4386

DFP-0 might be changed to DFP-1

ok, i now have:


so that looks hopeful. (I notice the values to 5 decimal places but assuming things are rounded properly it should match I presume?) Ah, the 'current="true"' when i start playing a movie is a bit of a giveaway isn't it. it's using it.

The fps: figure on the 'o' pane is more consistently staying at 23.98 now, though with occasional fluctuations to 23.95 and 24.00. I don't know if that fluctuation (not associated with any visible playback glitches) is important, but there's less of it at this speed now.

Yes, I think I have other, unrelated occasional glitches that I suppose are going to be my next project to track down. An occasional drop in framerate but not associated with a rise in the dropped-frame count (huh?). I am playing raw bluray rips through this now - ie: not transocded, so with a bitrate typically beween 30-40 MBit/sec - which shouldn't be a problem on a gigabit network of course. But that's another topic for another day; tennis final on soon...

Don't bother about the fluctuating fps shown on the codec screen. This is a measured value and not expected to be too precise.

I have been working on this occasional glitches for more than a year. In case you use vdpau you can try this testing branch mentioned here:
http://forum.xbmc.org/showthread.php?tid=116996
The thread is about XvBA but it does also include other work.

(2012-07-08 14:46)FernetMenta Wrote:  Don't bother about the fluctuating fps shown on the codec screen. This is a measured value and not expected to be too precise.

I have been working on this occasional glitches for more than a year. In case you use vdpau you can try this testing branch mentioned here:
http://forum.xbmc.org/showthread.php?tid=116996
The thread is about XvBA but it does also include other work.

i do use vdpau yes; currently ubuntu 12.04 64-bit with the xbmc eden from the ubuntu repos.

I'll try https://launchpad.net/~wsnipex/+archive/...ba-testing later as that one seems the most relevant. (wimbledon on now...)

well, i was about to say it's too broken to use, but then I thought I'd delete ~/.xbmc and start again and it was much better. I think this is me onto audio engine as well, presumably, and that seems to be working, having also found and configured my audio devices right away (beforehand that was a chore on this mac until i found the exact custom incantation). Also for the first time in linux i have working gui sounds *and* audio tracks in playback. however, truehd playback (in software) breaks horribly and truehd-passthru to capable amp is unselectable at present.

Some issues i'm having to think about before committing to it. For some reason it seems to have problems selecting the right refresh rate for *some* content. for instance starting to play for a few seconds and *then* deciding to switch, and on one example never switching at all. So far this seems to be the output of handbrake from off-air recordings; both progressive and interlaced; but not a big enough sample to be sure of that pattern yet.

Also still seeing the fps value wandering around a bit on tv content (eg: interlaced stuff with any of the bob/weave deinterlace types selected, it shows rates fluctuating around the 50 or 59.94 figure appropriate to content. Looks OK to the eye though.

OTOH watching a movie it *does* look to be rock-solid at 23.98 so far, which is the problem for which you suggested i tried this build.

(2012-07-08 20:58)Rachel Wrote:  Some issues i'm having to think about before committing to it. For some reason it seems to have problems selecting the right refresh rate for *some* content. for instance starting to play for a few seconds and *then* deciding to switch, and on one example never switching at all. So far this seems to be the output of handbrake from off-air recordings; both progressive and interlaced; but not a big enough sample to be sure of that pattern yet.

Difference seems to be it happens (often, not always) on videos with a frame rate mode of "Variable", which handbrake does as default. But I know that's offtopic for here, need to report that properly elsewhere.

edit: for reference and crosslinking, bug reported here: http://forum.xbmc.org/showthread.php?tid...pid1143341 in the thread where this build came from.

(2012-07-07 01:37)robo989 Wrote:  

(2012-06-26 21:22)Rachel Wrote:  i had to modify the script too to run on 12.04. My modifications:

Lines 50 & 51, change gdm to lightdm

Line 59 (this might be the one you need) change "cut -c32-" to "cut -c31-". It was truncating the first character of each line of the edid.

With those changes the script ran flawlessly here.

This worked a treat for me right off the bat on 12.04 frodo release from xbmcfreak.

Thanks ever so much.

Actually, this does work a treat for most stuff, but sources that are 24fps have a stutter, or frame doubling or whatever it's called as they are being output at 23.976 fps. (GT430)

Is there a fix for this?

Thanks, everything else works fine, so that's about 95%+ of my encoded MKVs...just the 24fps ones are the problem (23.976 ones - perfect - just to be clear).

Thanks,

(2012-07-11 17:21)robo989 Wrote:  

(2012-07-07 01:37)robo989 Wrote:  

(2012-06-26 21:22)Rachel Wrote:  i had to modify the script too to run on 12.04. My modifications:

Lines 50 & 51, change gdm to lightdm

Line 59 (this might be the one you need) change "cut -c32-" to "cut -c31-". It was truncating the first character of each line of the edid.

With those changes the script ran flawlessly here.

This worked a treat for me right off the bat on 12.04 frodo release from xbmcfreak.

Thanks ever so much.

Actually, this does work a treat for most stuff, but sources that are 24fps have a stutter, or frame doubling or whatever it's called as they are being output at 23.976 fps. (GT430)

Is there a fix for this?

Thanks, everything else works fine, so that's about 95%+ of my encoded MKVs...just the 24fps ones are the problem (23.976 ones - perfect - just to be clear).

Thanks,

Not sure - though I do have an exact 24p movie i can try that on later. But I expect now the way forward is as per FernetMenta's recommendation - the nvidia driver 302.17, his xorg.conf, letting xrandr select exactly the mode it wants. Seems to be working for me anyway, though I'm also on the testing branch mentioned above but that's probably an optional step.

(2010-03-17 16:12)JumJum Wrote:  OUTDATED with NVidia driver 302.17!!!!!
(It has support for xrandr 1.2/1.3 and can distinguish between 23.976 and 24)

Hang on there, does that mean this guide isn't needed and this is all dealt with no intervention, or the guide doesn't work for 302.17!?

(2012-07-11 17:26)robo989 Wrote:  

(2010-03-17 16:12)JumJum Wrote:  OUTDATED with NVidia driver 302.17!!!!!
(It has support for xrandr 1.2/1.3 and can distinguish between 23.976 and 24)

Hang on there, does that mean this guide isn't needed and this is all dealt with no intervention, or the guide doesn't work for 302.17!?

It seems it wants the modeline added to an xorg.conf (which therefore needs to exist) so it's not all working with no intervention, but it's an alternative approach to the fix at the top of this thread and basically amounts to "use *this* xorg.conf and install nvidia 302.17+"