[geekmiki]

Hi,

Weird question I guess, but here's my situation:
I have an Asrock ION 330 running Ubuntu 9.04 minimal+XBMC 9.11 Beta 1, connected to an Onkyo TX-SR507, the display is a Panasonic TX-P50G10 plasma TV.
I've spent quite a long time trying to get the refresh rate match the frame rate and I came up with the following 3 modlines in my xorg.conf, since this is what matches best the content I have:
-Modline 1: 23.976 Hz, obviously for all the SD and HD (720p and 1080p) files encoded at 23.976fps (about 90% of what I watch)
-Modline 2: 50 Hz, for all the 25fps encoded files
-Modline 3: 60Hz for all the 29.97 and 30 fps content I have (less than 2%)

Basically 90% of what I watch is based on the first modline at 23.976.

Now, since I found out about judder and refresh rate sync, I've become psycho about it and I focus so much on judder that I don't even know how smooth a 23.976fps movie should be on a screen that supports that resolution. Are 23.976 files supposed to have a very small judder due to the low framerate or is everything supposed to look as smooth as for example a DVD on an LCD with 100Hz activated (you know, that ultra smooth effect you get)... As said, I get a slight judder on travellings and quick camera movements, but nothing compared to a 24p movie playing on a 60Hz display.

I know it's hard to describe with words, but any opinion would be appreciated.

Thanks!

[ronnylov]

There will be some "stuttering" at camera pannings just because of the low framerate. You can see this also at the cinema. Thing is that it should stutter at the same frequency and not go fast-slow-fast-slow.

I halve solved this problem differently. I watch maybe 10% 23.976 fps material, 89 % 25 fps and 50 fps and <1 % 30 fps and 60 fps. So I have only one 50 Hz modeline and then I set "sync vidoeo to display" and "resample audio" as sync method. This is because my TV does not support 24 Hz, only 50 Hz and 60 Hz (and I don't care about the 60 Hz). Now what happens is that 23.976 is played at 25 fps but still with audio in sync (because of audio resampling). So everything is very smooth as it should be. It also works when VDPAU is used (my 1080 24p sample played perfectly at 25 fps).

So maybe you can try "sync to display" and "resample audio" in the settings (I am using 9.11 beta1 by the way). Slight fps errors in the media file will be corrected at playback synced to the display and since your TV supports 24 fps you my not notice any difference at all.

When I press the play button during playback I can see some information. It shows something like speed +4.271% and error 0% when I play 23.976 fps video at 25 Hz on my 50 Hz TV. If the values are constant and not fluctuating and error is 0% and I can not notice any lipsync problems then I assume that everything is fine. I do not mind this faster playback speed. In fact all movies released on PAL DVD are normally 24 fps played back at 25 fps so it is the same thing as watch a PAL DVD on a PAL TV.

[chrisinthesun]

I use the same resample approach to playback 23.97fps files at 25fps in 50hz on my Bravia (which is not 24p capable).

I've not noticed any audio syncing problems on movies so far. Occasionally I get minor syncing issues on some series episodes, but I put this down to bad file encoding as I had the same issue with some series episodes on my TVIX box.

It took me hours over the last 3 weeks to arrive at a combination of XBMC and xorg.conf settings that I "think" work for me (famous last words!)

[WWWilco]

Yet another one with, what it seems, the same problems as me:
http://forum.xbmc.org/showthread.php?tid=63531

It looks like the ION platform is just to slow or to buggy to play 1080p without any judder or stuttering. (i'm talking about a little bit of juddering here)