MKVToolNix is a free application for editing MKV files. With the free app you can cut a large file into smaller pieces, or vice versa to join smaller pieces to a larger one. You can save the sound of MKV to Mp3 but also embed subtitles very easily.
It's a very practical tool for those who have HD movies on their PC and want to edit them.
The developer of MKVToolnix project Moritz Bunkus announced the release of the new MKVToolnix 15.0.0. It's a great version of open-source and cross-platform (Windows, Linux and Unix) application of MKV (Matroska).
MKVToolNix 15.0.0 "Duel with the Devil" was released just one month after the release of MKVToolNix 14.0.0 "Flow", and seems to add a lot of new features and improvements, along with several bug fixes and some system changes.
The new MKVToolnix 15.0.0 comes with a new, much more practical GUI that supports editing video color features.
You can see all changes from release notes and of course to