Mac users interested in Matroska mkvtoolnix generally download:
Create, edit, and play Matroska video files (MKV) on your Mac. Use a common way or the command-line to access the application, select files, modify them, edit tags, and chapters. Adjust the aspect ratio, display width and height, FPS, and other parameters.
Additional suggestions for Matroska mkvtoolnix by our robot:
GUI for mkvextract (one tool of MkvToolnix).
tool of MkvToolnix). This program...parts from a Matroska
Batch GUI for mkvpropedit (part of MKVToolNix) written in Java.
(part of MKVToolNix)