After searching the whole internet for a Mac OSX binary built of ffmpeg with non free codecs included i finally gave up and wrote my own building script.
Since I wanted a statically compiled binary which also can be used on devices without Xcode installed, homebrew was not the perfect solution for me.
I started from scratch building a script that automatically downloads all dependencies and compiles all necessary libraries.
My final script can be found on github: https://github.com/markus-perl/ffmpeg-build-script