Thanks for your info, Andrea. Surely I am not helping you about
the native thread "MKV containers", then I am sorry.
Time ago I found "getgop.sh" script by Dan Dennedy.
I added a compressed file. Inside, you find the script and my
"readme" for the info (too many things to remember, then I usually
write a lot of readme files). Maybe there are others programs like
"Mediainfo", more user friendly, but I don't know if the GOP value
is calculated by them.
IgorBeg