Slight Judder with VDPAU

I know exactly what you mean as I have seen it on my Linux box, but I want to say that I ALSO see it on my Mac Mini running the XBMC port for OSX natively as well. I used to run Ubuntu on that box but went native when OSX to acceleration (though I believe it only worked on the Nvidia card Mac Minis as well, so this may be the same VDPAU acceleration).

But I can agree I see it and it is very frustrating. Never does it at the same spot if you rewind, very noticeable, as if frames are getting dropped and things suddenly slow down for 2-3 seconds, but I don't believe when I pop up the GUI it actually reports that it dropped frames.

I do use SMB shares and it happens when streaming mkv content of 720p or 1080p, I don't watch a lot of SD content so it's tough to say if it does it with SD as well. Interesting thing to see above someone suggested it might be SMB causing the issue, first I ever saw that mentioned before.

BDPNA Wrote:I know exactly what you mean as I have seen it on my Linux box, but I want to say that I ALSO see it on my Mac Mini running the XBMC port for OSX natively as well. I used to run Ubuntu on that box but went native when OSX to acceleration (though I believe it only worked on the Nvidia card Mac Minis as well, so this may be the same VDPAU acceleration).

But I can agree I see it and it is very frustrating. Never does it at the same spot if you rewind, very noticeable, as if frames are getting dropped and things suddenly slow down for 2-3 seconds, but I don't believe when I pop up the GUI it actually reports that it dropped frames.

I do use SMB shares and it happens when streaming mkv content of 720p or 1080p, I don't watch a lot of SD content so it's tough to say if it does it with SD as well. Interesting thing to see above someone suggested it might be SMB causing the issue, first I ever saw that mentioned before.

I have the EXACT same thing. Everytime I watch an HD movie (all 1080p) certain scenes goes into a slowmo for a split second or so, and rewinding doesn't fabricate the error.

Update: Watched braveheart 1080p (24p - x264 4.1) I counted at least 5-8 scenes where this "slowmo" occurred. Checking the output log shows 50 frames dropped in the entire movie, about 2 hours.

SMB isn't the issue, all of my content is all local or streamed from a sever with smb. Braveheart was all local.

I also have 1GB switches just in case.

Seeing the same here. Running from a 9.11 bootdisc everything ran fine, might be worth a check for you as well. Some of my scenes are reproduceable though, always in the same parts.

greenfish Wrote:I have the EXACT same thing. Everytime I watch an HD movie (all 1080p) certain scenes goes into a slowmo for a split second or so, and rewinding doesn't fabricate the error.

Update: Watched braveheart 1080p (24p - x264 4.1) I counted at least 5-8 scenes where this "slowmo" occurred. Checking the output log shows 50 frames dropped in the entire movie, about 2 hours.

SMB isn't the issue, all of my content is all local or streamed from a sever with smb. Braveheart was all local.

I also have 1GB switches just in case.

I can confirm the exact same issue of the "slowmo" experience. Posted my debug logs as well in another topic about this here.

The problem occurs to me on two pc's, both with more than adequate specs from local disks as well as a full gigabit cat 6 cabled network.

I get a lot of these in my logs;

560.17:46:05 T:2928913264 M:1888010240 DEBUG: CPullupCorrection: pattern lost
561.17:46:07 T:2928913264 M:1887883264 DEBUG: CPullupCorrection: detected pattern of length 24: 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00
562.17:46:58 T:2928913264 M:1888272384 DEBUG: CPullupCorrection: pattern lost
563.17:47:00 T:2928913264 M:1888272384 DEBUG: CPullupCorrection: detected pattern of length 24: 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00
564.17:47:50 T:2928913264 M:1888407552 DEBUG: CPullupCorrection: pattern lost
565.17:47:52 T:2928913264 M:1888440320 DEBUG: CPullupCorrection: detected pattern of length 24: 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00 41000.00 42000.00 42000.00 42000.00 41000.00 42000.00 42000.00

Don't know what they mean but they seem to be connected to the "slomo" effect I'm experiencing.

It happens on both the XBMCBuntu install on a ubuntu 10.04.01 LTS Server as well as an install of the XBMC 10 Live cd (or running the live cd on it's own)

Hopefully the cause of this will be found soon because it's driving me nuts.

Same here - in each of these slowmo-stutters xbmc drops 5 to 7 frames here... but i can't see anything in the log...

Whoa...this thread has gotten away from what I am experiencing.

Mine is a single frame "skip" that does not even register as a frame drop. My wife actually does not notice it (I wish it was the same for me, of course my wife also thinks dvd looks about the same as blu-ray...)

So, I have played with driver roll back. Went through the last 5 drivers.. issue actually got worse! (even more convincing me of VDPAU)

Played with BIOS settings, since my sata controller and my NIC are on the PCI bus, I decided to adjust the latency. Was set at 64, got better setting at 128, even better at 160...so I went for broke, set it at 255. Yikes! It all went to hell. Reset it at 160 cycles.

It is still there, but but less often so I guess I can live with it. What is annoying is my $70 WD Live Plus box plays back flawlessly..and that is over a upnp stream! And of course my BluRay player play w/o a hiccup.

It is all really disappointing, since I was really looking to ditch all physical media (keep it as a backup, but put everything on the spinning discs). As of now, it is not possible; I still need my Blu-ray player for reference playback.

Interesting the "slow-down" issues everyone else seems do have does not plague me? I have turn off all power-saving. So both my GPU and CPU are running full bore (my machine is in a different room with 50ft of HDMI cable, so noise is not an issue) Could the stutter people are having be from their machine ramping to play more intensive video?

My wife is SO happy I have finished my thesis so I can waste all my time on something that she cannot see! </sarcasm>

See if this help you with those momentary skips. In my case I need to tweak a custom modeline in xorg to iron out the very small frame rate mismatch that caused those skips. Scroll to the second post in order to avoid my rant and get the meat of the discussion.

http://forum.xbmc.org/showthread.php?tid=91013

This will not help if you're having actual frames dropping.

If you don't have modelines in your xorg.conf to work with you can try the standard 24 or 23.976 modes I've listed, or you can create them based on what the nvidia driver extracted from the EDID it received from your tv. The sequence of numbers nvidia outputs in those log lines is just a mode line broken out into multiple pairs of numbers.

Hope it helps.

--Chris

simonp Wrote:See if this help you with those momentary skips. In my case I need to tweak a custom modeline in xorg to iron out the very small frame rate mismatch that caused those skips. Scroll to the second post in order to avoid my rant and get the meat of the discussion.

http://forum.xbmc.org/showthread.php?tid=91013

This will not help if you're having actual frames dropping.

If you don't have modelines in your xorg.conf to work with you can try the standard 24 or 23.976 modes I've listed, or you can create them based on what the nvidia driver extracted from the EDID it received from your tv. The sequence of numbers nvidia outputs in those log lines is just a mode line broken out into multiple pairs of numbers.

Hope it helps.

--Chris

Wow, Chris. I think you have hit the nail on the head with what you are seeing. I will tackle this tomorrow. I am 2 martinis down right now and I have learned the hard way, troubleshooting and alcohol do not mix!

Side note, just for poops and giggles I turned off frame rate matching (ie everything is at 1080p60) and the "issue" went away.

I was thinking maybe VDPAU is incorrectly using 2:3 pulldown all the time, even if the source is 24p. But, now, Chris, you have me dismissing that idea right away. I am sure what you experience is what I am. The thing about your gf not noticing sold me! (my wife thinks I am crazy!)

- Mark

Chris, well cluck me!

You totally fixed the issue for me!!!!!

Thank your for your post with its excellent write-up!

Whew, now back to ripping my Blu-rays!