Show HN: Creating custom coloring pages from photos. Great for parents/teachers (portraitart.app)

Use a personal domain with a default address that filters to a mailbox then use a different email address for every site you use. This plus random passwords from a password manager contains the privacy leakage, blast radius of credential loss, and keeps your mail spam free.

Have to send user notification in email, because the processing queue could be long.

They don't validate the email, so just register with whatever@portraitart.app and let them spam themselves.

First thing I wanted to do was upload a family photo for my son. But of course, I don't want my family photo used for anything...

Good suggestion. We do not used the data for training. We will clarify that in FAQ.

I think this is just a thin wrapper around GPT-4 or similar? Parents I know have replaced colouring books by just asking GPT-4 , and the colouring pages it generates look exactly like the example outputs here.

Good catch! You are really into the details.

Did you see the goose's feet? One is a wine glass stem kind of a thing, or a liquid pour; the other is a pyramid.

The suspension is attached to the rounded bar next to it. You can find more pictures of it using Google.

The BMW R60 image appears to be CGI / 3D-rendered. If you zoom in on the original[1], you can see how the rear suspension is attached.

[1]: https://www.pexels.com/photo/orange-and-black-bmw-motorcycle...

The tool is not perfect. Sometimes it does not fully understand the image content. Also, right now, the image is slightly watermarked, but perfectly fine for using as coloring page.

And it seems personalized coloring page is very popular, we actually just decided to make the coloring pages free of watermarks, as our minor contribution to education. Will change the code to make that happen soon (in a few days).

Any prompt I can use?

Just fill in pa-contact@photofairy.ai for the address.

Honestly, when I first started reading your comment I thought you were being over sensitive but I totally get it looking at pictures 3 and 4. Even 5 and 6 completely changes the hairstyle.

This was absolutely my first reaction as well. I scrolled through the first few photos of White families where it seemed to turn even them into 1950s caricatures of "small town White Americans" and thought "hmmm, how's it going to treat Black people?"

I was not at all surprised when it turned Black people into White people.

This to me is one of the clearest examples I've seen of what people talk about when they talk about biases in training data. Clearly the training data of "coloring books" is heavily biased towards "stereotypical 1950s white people" and turns everyone into them.

(And you can add [1] and [2] to your list of comparison images.)

1. https://portraitart.app/static/gallery/father1_original_1024...

2. https://portraitart.app/static/gallery/father1_coloring_page...

With less "artistic license" [1]

We use a model but not a diffusion model + controlnet which is what I'm assuming this website does.

Would love any feedback on the results + site [2] – before it's asked: we do not use any user uploaded images for model training, they're only stored to show you the color version of your originally uploaded image

[1] https://static.dreamandcolor.com/aa828ad1-5696-4d4e-95eb-bcd...

[2] https://dreamandcolor.com/

It turned my black dog into a beagle!

Another – presumably coincidental – issue with images [1] and [2] is that there is a person missing. I assume that’s not related to skin colour, but to me it adds to the slightly irritating effect of how the resulting images may be disconnected from human reality in ways that would commonly be understood as disrespectful. (Not to speak of the “usual” AI problems, such as additional fingers, stray body parts, etc.)

[1]: https://portraitart.app/static/gallery/group1_original_1024....

[2]: https://portraitart.app/static/gallery/group1_coloring_page_...

Thanks for pointing this out, seriously. As a white european guy, I'd probably never have thought of this issue, that's an important reminder about our biases

No to mention the hand on the shoulder of the dude on the right in [2] has six fingers...

Same here - I had a web-based system that let you do coloring pages, paint-by-number, cross-stitch patterns, etc... and it all worked in the web session. While adding an AI element does give improvements over my results. I'm not sure those improvements are worth being prompted for my email, waiting even longer for results, the results not being 100% true to the original content, and not having those results just show on-screen.

1. You probably won't hit 100% parity just by prompt engineering especially if you want to do your points 3-4. You would need to train a style LoRa.

2. You can use one of the many ip-adapter models but the best result would probably be a combination of ip-adapter + subject LoRa.

3. That would be a controlnet model probably sketch best results would be achieved (for poses) using open or dw pose models.

4. You would do that with inpainting or stable drag.

https://stable-diffusion-art.com is a good starting point.

> 1. What's the style name for dilbert-like comic strips? Comic? Line art?

I don't think there's a clear settled name for that specific style, but I'd describe it as an American newspaper strip with low levels of detail and inspiration from "ligne claire" (Ligne claire is the style of Tintin etc. - focuses on strong, clear lines with a lot of details omitted, rarely shading very rarely hatching; e.g. hair in Ligne Claire is usually described by its borders - even messy hair is mostly hinted at by tufts sticking out, with the rest flat shaded).

American newspaper strips by no means always use simple line work, so describing it as that in isolation is unlikely to work, but it has other characteristics (which are by no means universal - this is a regular complication in categorizing this), such as often omitting backgrounds, or just hinting at backgrounds (e.g. with a picture hanging on a wall being all you see of the wall), and often using panels that change little or sometimes not at all during a conversational exchange (basically strips have a lot of characteristics around streamlining works for artists on a deadline that's often a major stress factor, so lots of simplification, but what requires simplification to same the artist time will vary greatly).

But there is variation there too, and especially very significant variation between the classic single-strip-a-day format and the Sunday format with a bigger panel, where you often end up seeing non-traditional layout or characters "bursting out" of individual frames in various ways where the single strips are often far more regimented. Many comics do both, and will sometimes look very different between the two.

E.g. Calvin and Hobbes strips are fairly regimented, usually four panels of near uniform size, while the Sunday panels were renowned for breaking "rules" with uneven, sometimes overlapping panels, and drawings bursting out of them - the last ever Calvin and Hobbes consists of 3 or 5 or 7 frames depending on how you count - the first frame contains another frame, which contains a drawing, which contains another frame with a drawing. The two top outer frames don't even align with the bottom outer frame... [1]

You almost certainly would need to try multiple things and add additional descriptors to get the specific feel you want.

[1] https://www.washingtonpost.com/arts-entertainment/2020/12/31...

>1. What's the style name for dilbert-like comic strips? Comic? Line art?

"style of Scott Adams."

2. How do I produce consistent characters throughout the "comic box" and episodes?: controlnet "reference"

3. How do I hint the generation of the comic? E.g. I draw a stick figure of someone sitting, and it generates my character with that pose: controlnet "open pose/sketching"

4. How do I "refine" some parts of the generated image. For example I like the generated character, but I want the face to look different direction: inpainting

It's still basically impossible to get perfectly consistent character features across multiple images/without a massive amount of effort. These models have been trained to generate single/standalone images.

Maybe some of the Sora related tech (where it generates frames in parallel/each frame has the context of every other frame) for coherency can be used to improve the plain image generation stuff as well, ie being able to specify a character with multiple views (3/4, back, front etc) so that you can refer to that character in your prompt.

This one calls itself "#1 AI coloring page generator" https://colorbliss.art/

Heh, I used a photo of myself sitting on the couch with my chihuahua looking up at me over my laptop screen and it replaced her with a St Bernard. The hallucination is strong in this one.

When I saw this posted late last night, I was pretty excited since I have kids, but then realized it's just determining the basic idea of what it sees in the photo, and then drawing a new image from scratch that has those elements. What I wanted is something that takes the original photo and removes things from the image until we're left with some basic line drawings, so that the people in the coloring book actually look like the people in the photo! Their examples very obviously show how different the resulting image is from the original. If Google allowed you to search by saying "Find me a coloring book image where a dad is sitting behind 2 kids with his arms around them, and the daughter is on the left and the son is on the right" then we'd end up with results almost as good.

I'm no Photoshop expert, but someone else in this discussion pointed out that Photoshop has some filters or other tools that do edge detection and can yield much more accurate results. If the techniques could be replicated in a SaaS then you'd have a much better product. Of course, if it could be done in a desktop Mac app or an iOS app, I might choose that for privacy reasons.

You could try out our site [1] – we use an AI model but not a diffusion model (like OP is) to convert photos to line art, the resulting lines are less "smooth" but it better represents the original image

[1] https://dreamandcolor.com/

Right now we hear

Libera te ... me ...

Soon we'll hear

libera te tutemet ex inferis

I actually used this exact method in the early 2000s to make "coloring books" for local businesses using their own photographs. They would give them out and use them for marketing.

I wouldn't call simple edge detection "pretty good" colouring book generation. You're just gonna get all the edges of complex shapes; it needs to be cartoonified/simplified with having large contiguous patches of colour in mind.