Package mkvtoolnix

Matroska container manipulation utilities

https://mkvtoolnix.download/

Mkvtoolnix is a set of utilities to mux and demux audio, video and subtitle
streams into and from Matroska containers.

General Commands (Section 1)
mkvextract
This program extracts specific parts from a Matroska(TM) file to other useful formats. The first argument, mode, tells mkvextract(1) what to extract. Currently...
mkvmerge
This program takes the input from several media files and joins their streams (all of them or just a selection) into a Matroska(TM) file; see the Matroska(TM)...
mkvpropedit
This program analyses an existing Matroska(TM) file and modifies some of its properties. Then it writes those modifications to the existing file. Among the...