I have stumbled upon an interesting post on Bitcointalk, showcasing a prototype of an algorithm that can store data in images by modifying its pixels.
The data (Bitcoin private keys) is first encrypted with AES, and then "encoded" into the image by slightly modifying the pixels.
So, if someone malicious steals your phone, or hacks into your computer, how will they know that one of your cat photos contains hidden wealth?
And finally, yes, this technique could be used to store Steem keys as well.
Original Post - https://bitcointalk.org/index.php?topic=1562481.0
Github Page - https://github.com/wisdomcsharp/SSI_Bitcoin-Storage