[Pharo-users] How to store an image file as a method source

So how you guys covert image files to strings to be stored as method sources ? I want to make a custom GUI that will contain a lot of images and I am a bit on a dilema whether I should put the images as method source as we do already with pharo icons OR just link to external files and find how I can download those files from Pharo. No idea whats the best course of action . Any suggestions ?