For the people who need extra help, feel free to watch this video. Some things have changed since that video and I got rid of the EasyMenu program support due to maintaining multiple way's to build GDE GoZen was time consuming.
Tip
Compiling the GDExtension for every platform you want to support can be time consuming, if you don't want to compile the GDExtension yourself and want to easily get new compiled builds on new version releases of GDE GoZen then you can always get the addon from my ko-fi page and from itch.io.
The build process needs to be done through the terminal. There is no other way of compiling it
Install python 3, scons, and git! You will also need to initialize the submodules of the git repo with git submodule update --init --recursive. Updating the submodules can be done with git submodule update --recursive --remote.
You'll also need aom installed. If you don't care for AV1 support, you can delete the lines containing libaom.
To start compiling the GDExtension, run python3 build.py. You'll need to select the options you want and to select for which platform and architecture you want to build GDE GoZen for. The building does take some time as you will need to compile both FFmpeg and the GDExtension. However, the build.py script makes everything very straightforward. Do remember though that you will need to say yes to compiling FFmpeg, without FFmpeg this won't work.
For Window builds you will need WSL installed, without this you won't be able to compile FFmpeg or the GDExtension. If you are building for Windows on WSL, you will need to compile lib aom with mingw on your WSL install first to have AV1 support.
If you don't need AV1 support, you can delete the lines containing libaom from the build.py file.
I recommend compiling on a Linux system since it'll go a lot smoother, just be certain to install mingw and if you want AV1 support you should compile lib aom with mingw. Some distro's such as Arch Linux can install lib aom with mingw through the AUR which speeds things up.
Due to MacOS being made by Apple, you will need an MacOS device for making the compiling work. There isn't much I can do about this sadly enough and compiled builds may also need their library files to be approved by the user before the GDExtension becomes accepted/usable on the MacOS system.
For compiling you will need aom and pkg-config installed through brew.
Web builds are only partially working. There is no audio support, no AV1 support, no access to system files due to Godot web builds running in a sandbox, and performance is a lower compared to the other platform support. When compiling for Web you will need to follow the instructions which are in the comments in the build.py file.
Web builds aren't included in the official builds because of these reasons. Preferably you should use the build in Theora video playback which Godot provides.
Android builds need to make certain that permissions are set correctly when using. You will need Android-studio or install the SDK's manually. The compiling environment with emsdk should get setup correctly. Do note that building this is only possible on Linux. If you're on Windows, you have to use a VM or WSL. If you can export your Godot projects to Android already, than compiling GDE GoZen may work without issues. I'm by no means an Android developer so for problems compiling I would suggest creating an issue in the repo.
You can join our Discord server to ask for help, but before joining the Discord server because compiling doesn't work, please check if your submodules are properly initialized. If you run into some issues after trying, feel free to ask for help in the Discord server in the gozen-video-editor channel.
This error is most likely due to not having initialized the submodules. Check the FFmpeg folder to see if it's empty or not. Empty = not initialized. Not empty = Create an issue as something might be wrong (but show a screenshot of the not empty folder for confirmation).
Caution
At this moment only Linux, Windows, Web, MacOS, and Android are supported! Compiling on Windows, however, may come with some challenges and may not always work if you don't have the correct tools installed such as python, scons, git, ... Also, compiling on MacOS can only be done by using a MacOS system. Compiling Android comes with challenges of setting up your system correctly and is generally advised to do this on a Linux machine.