MKVToolnix is a set of tools to create, alter and inspect Matroska
(and WebM) files. With these tools one can:

* Get information about Matroska files (mkvinfo)
* Extract tracks/data from Matroska files (mkvextract)
* Create Matroska files from other media files (mkvmerge)
* Modify properties of existing Matroska files (mkvpropedit)

MKVToolnix requires libebml, libmatroska and wxGTK all of which
are available on Slackbuilds.org.