Following my last post I’ve been going through my DVD collection and fixing the forced subtitles for the films that have them.

I turns out there are 3 different arrangements for these forced subtitles:

  • “burned-in” to the film - that is part of the video track
  • Separate subtitle track for the forced subtitles (when I wrote my last post these were the only non-burned-in ones I had come across and setting the appropriate track flags is all that is required to sort these
  • Subtitle text individually marked as forced within the “normal” subtitle track - these are the most difficult to deal with and the subject of this post.

Two films with the latter that I have on DVD are “50 First Dates” and “Boondock Saints II: All Saints Day”.

To be sure I was on the right path with solving this, I asked for advice on the MakeMKV forum and was told:

MakeMKV does only support the extraction of forced “flagged” subtitles from the subtitle track for Blu-rays and NOT for DVDs. So for DVDs the only way is to extract the subtitle track from the MKV file, use BDsup2sub to save only the forced “flagged” subtitles to an new subtitle track and add them with “MKVToolNIX GUI”.

This confirmed my approach was correct. Unfortunately the tool I mentioned in my last post, MKVExtractGUI-2, does not seem to work with the current version of MKVToolNix so I found an alternative, gMKVExtractGui.

The process

  1. Extract all of the subtitle tracks using gMKVExtractGui.
  2. Use BDSup2Sub to load each subtitle track. It will tell you if there are forced subtitles in the track. Export the tracks, ticking the ‘forced only’ box, for those that do.
  3. Add the new subtitle tracks to the MKV file using MKVToolNix
  4. Set the default/forced flags appropriately on the new subtitle tracks