I made a website for this, so you can now use it from the browser, no installing needed. Link in the op.
Let me know if you find any bugs or want some new features.

Interesting idea, but I don't know how to do it with reasonable amount of circuitry. You would need to use a lot more inserters for each line and make sure they all work in sync. Maybe I'll make something like that in the future.

Click here to make your own images

https://giant.gfycat.com/WarmheartedOldfashionedArgentinehornedfrog.webm
out.webm

Because who doesn't need giant pictures in their factory?


Image processing

Each item on the belt is representing one pixel of the final image.

First step is figuring ...