If you’re in the intersection of Emacs and ImageMagick users, Blimp
may interest you. It’s an Emacs interface to the ImageMagick commands.
Take a look at the README on GitHub to see how it works and what it
can do.
I haven’t used ImageMagick in a long time so I haven’t tried Blimp. If
you do work with ImageMagick, this is a chance to integrate one more
workflow into Emacs. It almost makes me wish I had a need for ImageMagick.