Hello, spiders and other forest creatures!
Forgive me if it's not the right place, but I'm supervising a student project about automatic flat coloring of lineart, and I would use some help, in two forms:
a) some feedback if the tool we are trying to create makes any sense
b) comic pages with flat colors only (that we ofc. won't publish anywhere without permission).

If you are interested, let me know, and here are some details:

First, the project is mostly for fun (and credits) of the student who is doing it, it's not anything serious.
What we want to do is to take a tool like GMIC https://www.davidrevoy.com/article240/gmic-line-art-colorization and use some so-called machine learning to teach it how to assign colors without human help. The goal is a tool that will take your linearts and a reference, and color the repeating parts, like characters if they have specific colors. You would still need to color changing backgrounds and new elements, of course.

This sounds like a fantastic project!

Just so you're aware, a flatting tool very similar to this exists as a photoshop plugin, called Flatten Pro by Peltmade https://peltmade.com/psplugins-flatting.html

You might want to just double check and make sure they don't hold any copyrights or patents that could potentially cause troubles for similar tools. It shouldn't, but better safe than sorry!

Is your tool specific to Krita, or can it be used in other programs as well?

Thanks!



Thanks, good to know! I was surprised it's not built into Photoshop. But this seems to be an equivalent to one of the G'MIC filters (https://gmic.eu/), and what we want to do is one level higher, in a sense.



So, the G'MIC we are using is available in Krita, GIMP, Paint.NET, and online. Our version is not yet available anywhere, we are not at that stage yet ;) I guess it would be the easiest to integrate into Krita, but we are open to suggestions.

It could save time and precision. For people who still ink by hand and then colour on the computer (like me), this could be a big help because getting the nooks and crannies has always been a pet peeve of mine.

Heh even magic wand tool doesn't always fill the spaces correctly. I'm just not sure that automated coloring would be less or more work unless I played with it.

Good point, we should test our tool on paper/scanned lineart!



For now, it is certainly more work If/once we have something reasonable we will let you play with it!

For Photoshop, if you familiarize yourself with actions you can get most of the way there. Before I run the action, I make sure I'm on the color layer and that I have the selection that I want. Then, I use an action in Photoshop that does these steps:
1. expands the selection by 1-2 pixels (you can find this option under select -> modify)
2. fills with the foreground color
3. deselects the selection
I've also keybound it to shift_f2 so I don't have to find the actions panel every time.

I've also found that the "select subject" tool from photoshop CC also gets me part of the way there, if I've turned off all the drawing layers for the background. It does create a feathered edge, so make sure to turn that off if you try this tool! (you can remove feathering by clicking the button that says "select and mask...")