Thanks for your input :)
Currently, it's more of a dirty hack since I realized you can (ab)use data urls to create an awful hex editor for images with live preview.
While playing around with it, I realized how much more "fun" JPEGs are to mess around with due to how the compression works.
If I make a "sequel", I would take my time to learn how JPEG works with regards to what/how information is stored and provide a tool to make them more malleable.