Video stutter (judder) is driving me nuts!

[MickM]

I have a really annoying judder issue. Over the decades I've accumulated thousands of DVDs for which I used MacDVDRipper Pro (MDRP) to rip just the main movie (VIDEO_TS architecture only - no further compression) and stored the rips on a server connected to my new M1 Mac mini. The Mac's HDMI output goes to my AV receiver and the receiver output goes to my TV (a 6 month old high end 85" Samsung Neo QLED TV). I also have a Blu-ray player connected to the receiver.

If I play the DVDs on the Blu-ray player everything is great - no judder at all. That makes me think the TV and receiver are likely not the culprits. However, if I make an iso of the DVD and play the appropriate main movie VOB file via VLC (3.0.17) I get lots of judder. In researching all this, I found that setting the Mac's Displays preferences for a frame rate of 24Hz (the frame rate actually used in making movies) that the judder was minimized, although still very noticeable. Note that my 1920x1080 frame rate choices for the TV are 24, 25, 30, 50, 60 Hz.

I then tried different player software (Apple's DVDPlayer) for the iso and the judder is *tremendously* minimized compared to VLC! I also converted the main movie to a compressed m4v and, while that appears to cause less judder overall, playing the m4v file with Apple's DVDPlayer, QuickTimePlayer or TV app still yields way less judder than if I play the movie with VLC. It sure looks like VLC is my issue, but it also might be just be an obscure VLC preference setting causing the issue. I have tried hardware decoding on/off, Skip Frames on/off, Deinterlacing on/off, Cache min/max but didn't notice any changes. Does anybody have any thoughts about this?

[Star72]

MacBook Pro m1 max here with a stuttering problem in VLC when using external displays - 5k LG + Apple Thunderbolt 27” + iMac Target Display. I tracked the issue down to a setting in Mission Control ‘displays have separate spaces’ - if I deselect that setting any video I play in QuickTime or VLC stutters every 10 seconds. If I leave it selected everything is smooth. Strangely IINA is smooth regardless of the setting.

If you are a spaces user it is worth checking.

[MickM]

I think you have identified a separate issue i.e. unrelated to my post. I have a Mac mini that only has my TV connected to it and therefore doesn't have a multi-display spaces situation. Either way, I did deselect the Mission Control ‘displays have separate spaces’ setting and (after logging out/in) it still didn't make any difference. I've looked into this a little more and I believe I'm seeing a VLC issue that many others may have also reported over the past decade or more - and it's apparently still not fixed .

I did try IINA in the recent past, but recall it was awful for playing DVD structures (i.e. VIDEO_TS/VOB) because it glitches transitioning from one 2GB VOB file to the next, including sometimes deciding to show subtitles on a per VOB file basis. The only good DVD structure playing software on the Mac is Apple's DVDPlayer - but it requires a mounted DVD instead of an extracted movie file (there is a hack work-around, but it's kind of messy).

[MickM]

Thought I'd bump this post, I'm still of the opinion this is a bug in VLC. I also see this video stuttering in VIDEO_TS structures that have been converted to MKV files. It is really distracting - is there anybody out there interested in tackling this one?

[unidan]

Hi, can you upload the file?

[MickM]

I have a short movie that I made a while ago to highlight judder. I extracted some juttery segments of a few movies from DVDs - nothing was further compressed and the only thing I did was convert them to MKV and then join the segments using (from memory) makemkv. In VLC the mkv segments play exactly as they do in the ripped VIDEO_TS structure DVDs (again, no further compression - the movie sizes were unchanged). Here is the file:

https://www119.zippyshare.com/v/Bapd98w8/file.html

Here is a guide to help more easily identify the annoying bits
1. James Bond walking scene - watch the power line poles in the background
2. James Bond motion scene - watch all the building and window edges
3. Eyes Wide Open - bathtub poles and lamps
4. Eyes Wide Open - furniture pieces as they move to the bottom left of the screen
5. Lucy - mountains in the background.
6. Spencer - large trees crossing in the foreground
7. Spencer - furniture pieces as they move to the bottom left of the screen
8. Spencer - windows and wall pictures etc.

Please note that the bigger the TV or monitor you connect your Mac to the more noticeable the judder. That being said, the judder isn't noticeable at all when playing the DVDs themselves.

EDIT: I'd appreciate it if one of the developers could confirm the download worked and also confirm the judder. From a hardware perspective, I've tried this on a 2010 Mac mini, a 2021 Mac mini M1, and a 2019 MacBook Pro. I have not been able to try this on a PC based system.

[MickM]

Can anybody please confirm that my download link works and also if they see the judder? The link is only valid for 30 days.

[unidan]

Hi, it works, I've downloaded the file

[MickM]

Hi, it works, I've downloaded the file

Thanks! But you didn’t answer the $64,000 question - do you see horrible judder in the video (best noticed on a large window/monitor)? Please also mention your hardware setup in case that ends up mattering.

[PeeWee]

do you see horrible judder in the video (best noticed on a large window/monitor)? Please also mention your hardware setup in case that ends up mattering.

Thanks for the file. Yeah, it's really almost unwatchable.

MacBook Pro (16-inch, 2019)
2.6 GHz 6-Core Intel Core i7
Intel UHD Graphics 630 1536 MB

I arrived in this thread after noticing that some, but not all of my archived VIDEO_TS judder.
I first observed this a few months ago, but don't remember wich VLC version that was.
I don't watch much DVDs any more, and don't have this problem with faultless HD or BD files.

[MickM]

Thanks for confirming. Between this awful VLC judder bug, and VLC's inability to deal with forced subtitles, my entire library of ripped DVDs is effectively undermined. While I have given up believing the developers will ever fix the forced subtitles issue, I'm hopeful that with the judder test case file I have provided they can fix this issue.

If the developers believe the judder issue is not their problem but somebody else's (e.g. the developers of some 3rd party library they incorporate within VLC) then PLEASE say so and I'll attempt to raise awareness and get it fixed over there.

Also, in case that 3rd party is Apple (who, based on my experience, won't fix this ever) I'll really appreciate it if someone with a PC and/or linux system could also download my test case and see if the judder is present in that world.

[MickM]

I want to officially report this issue as a VLC bug. Is the correct way to do this to make a post on the VLC Feature Requests forum (even though this isn't a feature, it's a bug) or should I create an account on https://code.videolan.org and make a post there?

[unidan]

The correct process is creating an account on code.videolan.org/videolan/vlc and post the file there through streams.videolan.org/upload after having created the ticket. However, it's also possible it's coming from the file itself too.

Thanks! But you didn’t answer the $64,000 question - do you see horrible judder in the video (best noticed on a large window/monitor)? Please also mention your hardware setup in case that ends up mattering.

Yes, on multiple hardware, but I haven't checked the file yet.

[MickM]

Thanks for the guidance. The only thing I can offer regarding the file itself being the issue is that I have certainly observed less judder with Apple’s DVD Player, so that does implicate VLC. It’s just a gut feeling, but I suspect the video frame rate delivered by VLC isn’t doing the right thing in real time.

[MickM]

Sorry - I've been sidetracked for a few days. I have tried my best to create an account at code.videolan.org/videolan/vlc and I can't even get to first base - what an awful setup! When registering I make a user ID, provide my email address and a password and when I click on register the web page goes blank and just hangs. Tried this twice with the same result. The equally awful support options tell me to enter my email address to resend some email (that I never got in the first place) and when I do that I still don't get an email. There is no email address that I can find to tell somebody I'm having trouble. I'm stuck - I'd love to be able to make VLC better by reporting this bug but sadly the whole registering infrastructure is too messed up. Is there any other way I can report this bug or is there anybody I can email to assist with why I can't register?

[unidan]

Hi,

The past days (and regularly) we've suffered from spammer attack, which put the services down. You should be able to register now.

[MickM]

Could somebody please register me with code.videolan.org/videolan/vlc under the username MickM and email address mick.mueck@mac.com. I've tried several times and it's just broken every time I try. Alternatively, could somebody who is already registered report this bug. Sigh.

[Cream]

Probably a dumb suggestion but if you're sick of frame juddering then:

• Press Ctrl + J and note down the exact frame rate of the video. For example, most modern films run at 23.976024 FPS.

• Download ToastyX CRU from GitHub and add a custom resolution.

• My monitor doesn't seem to underclock below 40Hz so instead I multiplied the refresh rate by 2 (23.976024 x 2 = 47.952048) and then added it into my monitor's EDID extension block.

Now, I just switch my monitor to 48Hz before watching a video and it works like a charm, at least in experience. To make it easier to switch between resolutions, you can install HotKey Resolution Changer although it's by no means a necessity.

I hope it helps!

[MickM]

Given that my original zippyshare link expired after 30 days, I have modified and reposted the composite judder clip to dropbox and the following link should be available indefinitely:

https://www.dropbox.com/s/t39nry4el3nwv ... s.mkv?dl=0

Here is an UPDATED guide (I deleted a couple of the clips to make the file size smaller and re-ordered some of the clips) to help more easily identify the juddering bits
1. James Bond walking scene - watch the power line poles in the background
2. James Bond motion scene - watch all the building and window edges
3. Lucy - mountains in the background.
4. Spencer - windows and wall pictures etc.
5. Spencer - furniture pieces as they move to the bottom left of the screen
6. Spencer - large trees crossing in the foreground

Please note that the bigger the TV or monitor you connect your Mac to the more noticeable the judder. Just to reiterate, judder on my big screen isn't noticeable at all when playing the DVDs themselves via a regular DVD player but when the VOB files are played via VLC they judder like crazy.

[MickM]

Responding to Cream's post:
I'm on the Mac, so it's ⌘I (Media Information...) to see the frame rate. While I certainly agree that most modern films have a frame rate of 23.976024 FPS, I'm curiously seeing 29.970030 for the first random half dozen ripped movies I tried. That's quite unexpected! Just for interest sake, if you download the judder file (see the link in my previous post) what frame rate do you see for that?

I'm a little confused by your 3rd bullet point. Did you double the refresh rate being output by VLC or double the frame rate of your external monitor? I couldn't see any way to tweak VLC's output frame rate so I'm guessing it was for your monitor. In my original post, I did mention I played around with the frame rate of my external monitor (an 85" Samsung TV connected to my Mac mini) via my Mac's Display preferences settings and the judder was still there. Could you please try my judder video with and without your frame rate settings and report back with your conclusions. Thanks .