Issues with 4K UHD blu-rays that use seamless branching

[CrazyScientist]

Hi, all

First time posting, here - apologies if this query is in the wrong place!

I have been trying to rip some of my 4K UHD Blu-Rays to MKV files for the first time (being doing this for years with standard HD Blu-ray titles) and have been running into some issues with subtitle sync on discs with seamless branching. In this case, specifically, it's the Star Wars Saga 4K discs that are giving me grief.

The issue is that with each join of the segments, the subtitles in the latter segment are delayed by a fixed offset that is the same length as the previous segment. For example, if there are two segments in a title, with the first being 3 minutes long and the second being 10 minutes long, and there are subtitles throughout both segments, then after joining, the subtitles in the latter segment are all three minutes later than they should be. So, instead of a 13 minute title, you have one that is 16 minutes long with the audio/video streams only being 13 minutes long and the remaining three minutes being the delayed subtitles.

This is the process I'm using (and have been using for many years):

1) BDInfo to identify relevant mpls files
2) Demuxing using eac3to CLI to raw THD, h265, sup and chapter (txt) files
3) Remuxing into MKV using mkvtoolnix


I've attached the log file from the eac3to command run, if it's of any relevance.

Has anyone run into this issue before/have any feedback? Any input would be appreciated!

Thanks.

[johns0]

What software are you using to rip the 4 k discs?

[Ennio]

Other than johns0's idea, assuming the rip went ok, I'd try latest eac3to (v3.51) or DGDemux for demuxing.

DGDemux.exe is in the linked DGDecNV package, but with GUI can be downloaded at https://www.rationalqm.us/dgdemux/binaries/
Here too, be sure to use latest

[CrazyScientist]

Thanks for the replies, guys.

What software are you using to rip the 4 k discs?

Using MakeMKV to rip to BDMV folder structure, at the moment - had intended to refresh my AnyDVD licence but it seems the (free) MakeMKV does the trick, already!

Other than johns0's idea, assuming the rip went ok, I'd try latest eac3to (v3.51) or DGDemux for demuxing.

DGDemux.exe is in the linked DGDecNV package, but with GUI can be downloaded at https://www.rationalqm.us/dgdemux/binaries/
Here too, be sure to use latest

I'll give the latest eac3to a shout - hopefully it has been fixed!

[Ennio]

What software are you using to rip the 4 k discs?

Using MakeMKV to rip to BDMV folder structure, at the moment...

Yep, that's a good start. MakeMKV can drop stitches with seamlessly branched discs when directly ripping to mkv. Always use full disc backup first here. This goes for both BD and UHDBD.

[CrazyScientist]

Thanks so much for the pointers - I can confirm that using the latest version of eac3to for the demuxing stage seems to have addressed the issue.

Not sure what it was that was wrong, previously! In general, is it more or less advisable to use MakeMKV for the whole process? I did try MakeMKV after my initial attempt with eac3to failed, and found it did the job, but my preference has tended to be to use eac3to as I simply found it a more versatile tool for demuxing.

[Ennio]

In general, is it more or less advisable to use MakeMKV for the whole process? I did try MakeMKV after my initial attempt with eac3to failed, and found it did the job, but my preference has tended to be to use eac3to as I simply found it a more versatile tool for demuxing.

"In general", yes, MakeMKV does a proper job. But:

only with seamlessly branched discs I do not advice to let MakeMKV rip directly to mkv. Where I do advice to

1 - let MakeMKV rip to full-disc backup,
2 - demux this rip with eac3to or DGDemux and
3 - use these demuxed streams as inputs to the muxer application of choice

Obviously these three steps also work for non-seamlessly branched discs, but would take - unnecessary - more steps than MakeMKV directly ripping to mkv.