Forced only subtitle flag for PGS subtitles when hard coding to video

[MartyMcNuts]

Hi, I have been using -vpp-subburn quite often to hard code the subs from PGS into the video (4K UHD & 1080p bluray) but occasionally come across a movie where the PGS subs contain both full and forced subtitles.

I was wondering if you could add a "forced-only" flag so that just the forced subs in the PGS file can be hard coded in the video. I think FFMPEG has something like this.

I have zipped and attached a PGS sub file from "A Quiet Place" 4K UHD. This PGS file contains the both full and forced subs.

Cheers, MM

A QUIET PLACE_F1_T15_Subtitle - English.zip