Newbie 3D playback issues

Hi there!
First post from a Newbie.

I took the plunge and got myself a Vero 4K+ for the combined possibilities of 4K HDR and 3D instead of a my regular RPI 3B+ for 3D and Plexapp on TV for the 4K stuff.

The Vero plays 4K content flawless and - I didn’t think this would make such a difference - 3D MVC PQ is from another league compared to the Pi; that much better!

The only problem I have is that whatever you throw at the RPI 3B+ regarding 3D content just works in contrast to the Vero (my experience). That could be a rookie mistake (hopefully it is) or perhaps require some fiddling or simply doesn’t work. To be honest, for the most part they are subtitle related and - my bad - I’m not a native english speaker so I do need them most of the time. As the 3D capabilities probably are important to a fair portion of Vero users it might be handy to get some sort of sticky or wiki regarding this topic to guide users along the adventurous 3D path.

Some problems I encounter on Vero 4K+ 19.4:

  • 1920x1080p (3D SBS), -(3D TAB) and -(3D FP) settings won’t be properly saved in guisettings.xml, so screen calibration doesn’t survive a reboot. The first two don’t allow a sceen calibration anyway because it scrambles the screen.

  • 3D MVC FP, srt screen position adjustment won’t be saved (see 1st point) and (big bummer) PGS depth adjustment not working.

  • 3D TAB, srt screen position adjustment won’t be saved (see 1st point) and (bigger bummer) PGS bug sometimes text scaled wrong with off screen placement.

Can these issues be solved? That would be awsome because there is no going back :slight_smile:

It may make it easier for the OSMC guys to help you if you post some debug logs; if you’re not sure how to do that, see here:

@tanio99 may want to say something, as he is “3D guy” around here. :grinning:

I can confirm that screen adjustments simply don’t work when it comes to 3D playback :frowning: . That’s a known issue on my TODO list (with low prio unfortunately).

Before I start investigating the srt position and PSG scaling issue, I’d like to know if that also happens, if you don’t use any screen calibrations (you’ve mentioned, that they’re not saved, so I assume you are using them)?

Since @angry.sardine is the 3D/subtitle power user here: did you experience any regressions?

While this is obliviously a bug that hopefully can be fixed one day I wanted to check why you use screen calibration as we generally discourage the usage as it impact the picture quality and normally there should be no need for it’s usage

When setting screen calibration – try going to Power → Exit instead of reboot or shut down. Kodi should come back up after a few seconds, and you may find that the setting is now persistent



That isn’t something I’ve tested for a few weeks. :stuck_out_tongue: I’ll run a few test clips. I have to say, though, I don’t think I have many, if any, SBS or TAB clips with subtitles - my primary interest is MVC/frame-packed stuff.

One thing that did occur to me: if I remember correctly, you decided (and I agreed at the time it was a good idea) to make the Kodi subtitle depth setting affect only SRT subtitles, on the grounds that PGS subtitles taken straight from a 3D blu ray should have their own per-subtitle depth information stored in the video file; and if per-subtitle depth data is available, that will be set sensibly by the disc author, so there’s no need for an additional offset. But SRT subs have no built-in depth value, so they need to pay attention to the Kodi depth setting.

That makes sense so long as you’re watching a full remux of a 3D blu ray. However (it now occurs to me for the first time! :flushed:) it could be that someone might have transcoded the original 3D blu ray rather than simply remuxing it, and muxed the original PGS track into the transcode. If that happened then the video file might perhaps no longer contain the subtitle depth information. In that case, you might actually need PGS subtitle depth to be affected by Kodi’s depth setting in the same way that SRT subs are. This might account for @movieaddict having a problem with PGS subtitle depth. (And if you were trying to play a TAB or SBS file that has PGS subs mixed in, you might well encounter something like this).

@movieaddict Can you tell us the source of the file you’re having trouble with as regards PGS subs? Is it a direct remux from a disk? Is it definitely MVC? MKV, or ISO? Maybe uploading a short extract from the file would help?

As @tanio99 says, screen calibration has problems in 3D. As @fzinken says, Kodi’s screen calibration settings should be avoided whenever possible, even in 2D mode, as they have an adverse effect on image quality. If the picture is not being positioned correctly, there may be a setting on your TV that isn’t set properly. If you describe the issue and tell the guys what model your TV is, they may be able to suggest some settings on the TV to adjust.

How are you adjusting the screen position - by going into the calibration settings? My preferred way of adjusting this is to use the Keymap Editor add-on to assign two keys on the remote to move the subtitles up or down by one pixel - I use the volume control keys, as an external device handles my actual volume control. This lets you adjust subtitle position much more quickly and easily than going into calibration (which, as we’ve discussed, has problems in 3D). I won’t guarantee the setting will persist if you change it this way, but it might, and even if it doesn’t it will be less annoying to adjust it again next time!

I do this exactly the same way; 2 keys defined to shift up/down the subtitle and another key to use the screen calibration. i use the screen calibration just for the purpose of shifting the subtitle position in mainly non 3D screens as the shift up key doesn’t repeat (the shift down key does!) so when shifting subs I’ve to press the key many times and the setting (in 3D screens) won’t last after reboot nor exit.
In TopBottom 3D the shifting subs trick garbles the screen so I’ve to the content I have to reboot the Vero, as is the screen calibration. I don’t use SBS 3D but I can imagine it’s the same.

I just use sceen calibration to set the subtitle position as I don’t now another way beyond the shifting ‘trick’ that is a real pain in the #@s because It doesn’t last.

The TV is an LG E6V

Darn, doesn’t work.

Having run a few quick tests, I’m not seeing any problems with PGS subtitle depth on MVC videos - the per-subtitle depth setting seems to be working as expected.

I can confirm that the vertical position of SRT subtitles doesn’t persist across a reboot. (That may well not be a new problem, I don’t think it occurred to me to test that before).

I don’t have any subtitled TAB clips to test; if I have time tomorrow, I’ll see if I can find something.

Ah, okay. If you had been using it to (e.g.) correct overscan as well, that would have been a problem! :smiley:

Ah yes, that makes totally sense. I’ll put it on my todo list. I will add the depth setting then also for PGS subtitles.

I’ll have a look at it. Thanks for checking :+1:

Okay, I’ve done a bit of testing today with SBS and TAB files today. I’m afraid there’s quite a lot of Bad Stuff going on with them. :slightly_frowning_face:

What I’ve found so far:


PGS subtitles are working correctly as far as I can tell.

SRT subs are mostly working correctly, but if you set a subtitle height in the video calibration settings, this is ignored. Setting the vertical position directly from the remote (by mapping two keys, e.g. the volume buttons, to move subtitles up and down) works - but (as previously mentioned) altering this doesn’t persist across a reboot.


Two different SBS files are giving some weird flashing pixels down the right hand side of the screen.

Trying to change the position of SRT subs from the remote causes immediate picture loss, and you have to reboot to get the file to play again. Changing the subtitle position in calibration settings is, again, ignored.


I’m not getting a right-eye image at all! Also getting a line of brightly coloured noise along the top of the screen.

SRT subtitles have all the same issues as on SBS.

I’m having trouble finding any SBS or TAB clips with PGS subtitles at the moment, but I’ve no reason to doubt that @movieaddict 's findings are valid.

Final note: full-height TAB files (as opposed to half-TAB) seem to be more of a thing now than they used to be - there are a lot of files floating around with dimensions of 1920x2160, or 1920x1600. In an ideal world it would be nice to be able to translate these to Frame-Packed output on the fly, but that’s probably more work than is justified. But I think there’s a good chance people will try to play them sometimes, so you may need to think about what happens when they do. Warning message, maybe?

Whether the key repeats or not will depend on which key you choose. That’s one reason why I use the volume buttons - they both repeat.

@angry.sardine, thanks for testing it out!

Regarding the SRT issues, I can’t see how changing the position could cause a picture loss that even survives a playback stop/start. That SRT subtitle topic sounds extremely confusing to me. I definitely need to take a closer look at it.

The issues with SBS/TAB clips which you’ve mentioned sound interesting to me, because neither Kodi nor the kernel does anything special when playing such videos. We only set the SBS/TAB flag in the HDMI layer. So the SBS/TAB clip is sent to the monitor/TV/projector the same way as every other 2D clip.

Also TAB is working perfectly here. Maybe it’s related to the clips? Do you have some logs for me?

Regarding Full-TAB/SBS: the logic is partly implemented in the kernel but needs testing and I need to implement the missing bits. I think it can be done, I’m just lacking time :slight_smile: .

I’m currently investigating a flip-eyes issue when playing SBS/TAB files. That feature doesn’t work because the 3D logic in the kernel is inactive (as mentioned above) when playing such files. To make flip-eyes working I need to activate that 3D part but then I get just garbage out. I assume when I get that working, then that could also be a big step forward for Full-TAB/SBS support.

Once again thanks for your help and support, I think I owe you a beer or two :beers: !

Heh, no worries. :grinning: It’s generally to my advantage that this thing works as well as it can, so I’m happy to help.

That’s interesting! I will test a couple more videos. I should probably also double-check that my video processor isn’t doing something odd to the signal before it reaches the TV - it’s usually very reliable these days, but there’s always a small chance of a previously undetected bug for an unusual signal format. All this might have to wait till tomorrow… I’ll get back to you when I can (with logs, and sample clips, assuming everything is still reproducible).

Thanks for the tip, works now!

No rush, I’m already busy doing other 3D related things :rofl:

I have upload some samples to play with…

They all have the same subtitleset: PGS 3D (retail), PGS YELLOW (own creation from SRT) and SRT (created from OCR-ed PGS 3D)

Upload link: - 1668623546

PGS 3D => shows depth information, depth not adjustable
PGS YELLOW => shows depth information, depth not adjustable
SRT => no depth information, depth adjustable

PGS 3D => no depth information, depth adjustable, bug (sometimes big scaled off screen)
PGS YELLOW => no depth information, depth adjustable, bug (sometimes big scaled off screen)
SRT => no depth information, depth adjustable

PGS 3D => no depth information, depth adjustable, bug (sometimes big scaled off screen)
PGS YELLOW => no depth information, depth adjustable, bug (sometimes big scaled off screen)
SRT => no depth information, depth adjustable