Author's github: https://github.com/corkami/pics
He works on things like hash collisions, image files that contain an image of their own hash, "polyglot" files and such like.
I think this is intended as a "minimum viable mp4 file" to show what the required binary parts are.
If you want more file-format goodness, check out Ange Albertini's Corkami Project:
https://github.com/corkami/pics
Here are Windows and Linux executables:
https://raw.githubusercontent.com/corkami/pics/master/binary...
https://raw.githubusercontent.com/corkami/pics/master/binary...
This repo from the author is full of gold. Shows the details and visualization of various file structures (including multiple zip formats, image formats and executable files)