Jittery playback of few H264 video files

Hi,

The issue you are currently experiencing with OSMC
-I have noticed a sort of jittery playback on this series of video files I have been watching. It’s not buffering and it does not affect audio. I have played the same files on my macOS and Windows 10 machines and the jittery playback is not repro. I have also noticed this same behaviour in 1 other similar video file unrelated to this series.

What you were doing when this issue occurred
-Playback from my Vero 4K+
Whether you can replicate this issue on demand. If you can, then please provide some steps on how an OSMC developer can reproduce the same issue.
-Just normal playback with subtitles enabled

The device you are currently running OSMC on
What peripherals are attached to the device?
-Playback from my NAS via AVR (Denon 3700) on a wired network

Has this issue been introduced by a new version of OSMC? When did the issue first appear and can you recall a time when it was not present?
-I have noticed noticed this issue on the current OS release, and it’s not repro on other video files I have played from the same location

Log
-The log was captured during several tries at playing one of the files. The one in the log is just one of 5: https://paste.osmc.tv/kuqacuveqa

MediaInfo
https://paste.osmc.tv/tukixudohi.tex

Thanks in advance!

Looks like discontinuities in the stream. You could try setting Adjust Refresh Rate to Always to see if that improves things; otherwise it may be a bad rip.

Thank you. I’ll give that a try!

Is this possibly a 1080p/25fps video being output as 1080p/50Hz? If so, changing the output mode to 1080p/25Hz might help.

EDIT: Actually doing that would probably require you to whitelist some resolutions: see [HowTo] Guide to the Kodi whitelist function and related settings

I actually didn’t find the Always option in Adjust Refresh Rate. I’ll try the whitelist. Thanks for the input.

In case I wasn’t clear, just setting up the whitelist may not help: what you need to do is check that the output mode it’s using is 1080p/25Hz and not 1080p/50Hz. But setting up the whitelist is what allows you to manually change the output mode during playback.

I enabled log in mode and I can see on the OSD while the video is playing that the FPS goes to higher values like 80 and 90 fps. I guess it’s not supposed to do that since the framerate is supposed to be 25. I did try the whitelist but it didn’t help. I’ll assign this to a bad rip and move on. Thank you very much for your help on this matter!

Sounds like your video has a variable framerate. MediaInfo will tell you if this is the case. It didn’t seem to here which is interesting.

Variable frame rate videos are usually a burden for hardware video decoders which expect to get ‘hints’ and follow things from there. They can of course adapt, but if the frame rate is changing constantly, that’ll be an uphill battle.

Your video is 1080p, but if MediaInfo is to be trusted, it’s only 6Mbps. You might be able to play it in software by disabling H264 playback acceleration under Settings → Playback. You will need to re-enable it for more demanding content like an H264 1080p Blu-ray rip

Cheers

Sam

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Disabling H264 playback acceleration from Settings → Player → Playback did help. The video now plays smoothly. I don’t usually have this kind of problems so I will reenable it when I’m done and remember this work around. Thanks for tip. And I’m looking forward to hear about the new product.

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I’m glad to hear this has worked for you.