Black images when joining split movie using mkvtoolnix

[ElCholano]

hello, I have a blu ray movie divided into 2 discs, from those discs I made an mkv file with make mkv but when I put them together with mkvtoolnix they create 2 seconds of a black image, without sound without video, is there a way to configure mkvtoolnix so that this does not happen when joining separate Blu-ray discs? Another question, is there a way to remove those black seconds without rendering or how can I remove it with mkvtoolnix?

[netmask56]

You can't do frame accurate edits with mkv files unless you re-encode. Cutting or joining mkv files can only occur on I frames unless re-encoding.

[Ennio]

...when I put them together with mkvtoolnix they create 2 seconds of a black image, without sound without video...

What is meant by "they" ? You mean the software or your player(s) or...

If the few seconds with black and no sound is a part of the source video - at the end of part one, or the beginning of part 2 - at least smart-rendering (re-encoding only at joining point) is necessary, as netmask56 already stated. Where audio can raise issues too. Having no sound can point to silent audio being present.

Small chance the 2 seconds are created by the player. Where trying another one may help out.

[ProWo]

Remux both mkv to ts and join the two ts files.
Then remux the joined ts file back to mkv.
You can use clever Ffmpeg-GUI for this steps.