MKVToolNix is a set of tools to create, alter and inspect Matroska & WebM files under Windows, macOS, Linux and other Unices. It is the de-facto reference implementation of a Matroska multiplexer. MKVToolNix consists of the following command-line tools: mkvmerge is a tool to create Matroska & WebM files from other formats. MKVToolNix is an extensive collection of various utilities for the Matroska file format by Moritz Bunkos. The free and open-source Matroska library and tools are accessible for various operating systems including Linux, BSD and macOS. MKVToolnix Alternatives. MKVToolnix is described as 'set of tools to create, alter and inspect Matroska files under Linux, other Unices and Windows' and is a well-known app in the Video & Movies category. There are more than 25 alternatives to MKVToolnix for a variety of platforms, including Windows, Mac, Linux, Android and Android Tablet.
I streamed a few DJ sets over the last few weeks with a bunch of friends as part of ‘covidcore’, an online get-together while we’re all in isolation. It’s been a while since I’ve played any DJ sets but it was great fun and thankfully I didn’t make too many mistakes.
Anyway, It was my first streaming experience and I found it a breeze to set up thanks to Twitch and OBS. When reviewing my recordings I noticed that my microphone level was pretty low so I decided to bust out the audio track from the video and raise it. Also when uploading my video to Youtube I also got a copyright notice about one the clips in my video which was subsequently being blocked, so I decided to edit that out too.
Here is how you can do it.
Note: I’m on a mac so all of the instructions are for that, but apart from installation the rest should be platform agnostic.
Steps
Install mkvtoolnix
Extract audio and video tracks from mkv file
Optionally convert audio track if editing needed
Merge audio and video tracks back in to mkv file
Mkvtoolnix Online Login
Install mkvtoolnix
mkvtoolnix is a set of command line programs for finding out information and modifying mkv (“Matroska”) files. You can install it with a GUI but I didn’t bother.
That’s it, boom!
Mkvtoolnix online, free
Extract audio and video tracks from mkv file
For this step we are going to run this command
In the above command we are using mkvextract, part of mkvtoolnix, to extract the video track which is encoded using the ‘h264’ codec and also the audio track which is encoded using the AAC codec.
In order to find out what your video and audio tracks were encoded with use the following tool
Might be good to reference the docs if you have trouble there.
Optionally convert audio track if editing needed
My audio editor couldn’t open the aac file I created so I converted it to FLAC format using ffmpeg, another command line program that is insanely useful for converting audio formats (amongst other things).
So to convert I ran
Now I can open my flac file and edit the parts I want, like amplifying my microphone in the recording.
Merge audio and video tracks back in to mkv file
Right, now you have completed your editing we can stitch them back together again using the mkvmerge command
You can see I just merged the flac formatted audio back in. I just tried it and it worked. I need to read up a bit more on file formats to be honest so if you need more info check the docs.