[monkeytrumpet]

Hi Folks,

So I've spent the last couple of weeks reading posts, trying to find matching symptoms with a solution that works for me and to no avail so far... So I've reached the point of posting here.

Basically when I play back a 1080 / 24P MKV file (tried with DTS-MA, TrueHD) I end up getting very "juddery" playback - it looks like dropped frames however the dropped frame count doesn't increase on OSD (I tend to get about 9-30 dropped frames at the start of playback and then it stays solid).

Pastebin of trying to play back two files (both exhibited issues detailed above);

http://pastebin.com/g9qdXyh2

I've noticed a lot of "Decode - avcodec_decode_video returned failure" messages in the log, but I can't seem to find a consensus on what that means, or how to fix it.

My system is a Shuttle XS35GT
I'm running XBMC live having updated nvidia drivers & libvdpau1 as well as the general set of files updated apt-get update / apt-get upgrade.

Software Versions;
NVIDIA UNIX x86 Kernel Module 270.18
Linux build 2.6.32-26
XBMC Live 10.0 r35648

I have XBMC set up as follows;

• Match refresh rate to video refresh rate
  
• Use VDPAU
  
• Bilinear Upscaling
  
• do NOT sync playback to display
  

playback of mkv files which are not 24P works without a problem, CPU usage when playing back 24P content sits at around 6 - 15% / core.

I have already tried various combinations of XBMC settings (turning off match refresh rate, changing from bilinear to auto), I have also updated libvdpau from the ppa:nvidia-vdpau/ppa repository without it having an effect on the playback quality.

Any advice would be appreciated - and I'm happy to provide whatever additional information would help.

Matt

[gsgleason]

It seems like it would be related to the refresh rate of the monitor compared to that of the movie. I am on an HDTV with 60Hz refresh rate. I do NOT have Match refresh rate to video refresh rate enabled, and do not have the issue.

[monkeytrumpet]

hmm, gave that a try and it didn't make life better - in fact without matching refresh rates it was considerably worse (continuous juddering). Pastebin below showing results on this setting;

http://pastebin.com/Sj3rLB87

[monkeytrumpet]

Should probably mention - Shuttle XS35GT connects to a Yamaha Rx-V3900 which in turn is connected to a Sony Bravia KDL46X3100. All of the "game/text mode" junk and processing in the TV is turned off, as well as any processing within the Yamaha.

I have the modelines configured in the xorg.conf file as per guides around the forum on the topic of judder free 24P playback.

All of these video files play without a hitch on VLC on either mac or windows, and all are direct copies of my blu rays.

[monkeytrumpet]

well what do you know - the problem appears to have been that I incorporated;

<video>
<vdpauscaling>true</vdpauscaling>
</video>

into my advancedsettings.xml file - I put that in based upon other entries in the forum, but it appears to have made the playback fairly horrible... live and learn. Solved.

[bobo1on1]

You somehow didn't read the

<vdpauscaling>true</vdpauscaling> <!-- scales with vdpau instead of opengl and turns on its HQ scaler when available, enabling this might slow down rendering and cause framedrops especially on ion systems, this setting requires a vdpau feature set C gpu-->

from http://wiki.xbmc.org/index.php?title=Adv...3Cvideo.3E ? :p

[monkeytrumpet]

Nope, you are dead right there - I did do go through the wiki thoroughly during config, but I eventually found references to that particular setting in a thread and never cross checked against the wiki to see what caveats there may be. I did know that feature set c was required but I thought that was the only restriction. sorry!