Are there any non-esoteric programming languages that use image files as program source?

Question

I've seen Piet and perhaps some other esoteric programming languages that accept images as input. Is there any such language that's intended for real use? Other than the fact that it seems horrifically unreasonable to actually program this way, there is a certain allure to the idea that, as textual program source can be created in any old text editor, graphical program source could be created in any old image editor.

I love making programming languages, so if there's any interest, I might have a go at making one like this, if only as a fun diversion.

Edit: A now-deleted answer raises the subject of visual programming languages. While certainly related, such languages are typically specific to a single editor and application, and are thus neither image-based nor general-purpose. The situation does not look promising.

Answer 1

postscript? I don't think thats really what you meant, but it fits the bill, sort of. It's certainly the most widespread "image" based language. (Or maybe more like a language based image? It blurs the line between the two.)

You might also be interested in reading the "Designing a Design Tool" section of http://worrydream.com/MagicInk. It's not an implementation, but some interesting ideas.