(Claude Code transcript: https://gisthost.github.io/?58039ba5c1ca3ed177e8659168996ee4)
Wrote this up in more detail on my blog: https://simonwillison.net/2026/Jun/22/porting-moebius/
unet weights are in fp32. did you by any chance try something lower, fp16?
There are 25 or so mentions of fp16 and fp32 weights across the 7500+ words of Markdown text it generated. So the next question might be: Did it make the right calls?
https://github.com/simonw/moebius-web/blob/main/notes.md
https://github.com/simonw/moebius-web/blob/main/plan.md
https://github.com/simonw/moebius-web/blob/main/research.md
https://github.com/simonw/moebius-web/blob/main/understandin...
The weirdest thing was when the inpainting tool added strange people to an image. This singer was all decked out in tinsel and red, and the inpainting model added a grumpy old man in a top hat. I don't recall clicking the "Add creepy old man" button.
At the time this was Stable Diffusion on the backend, run by a variety of model hosting services, Amazon being one. They all had different requirements for the input image and that made things really complex. For some the aspect ratio was impossible to meet, and it would fail if the banner was 200x60. For others, you had to resize it before input, which meant you were adding an image with poor resolution to start. Garbage in, garbage out.
All of this to say, there is a lot of preproduction that went into it, and the client never ended up using my attempts.
Obvious reference to the Dickens story A Christmas Carol. In the UK there's a bylaw that requires Christmassy events to hire a Scrooge-like figure to lurk in the background so people keep their enthusiasm in check.
Thats because small models like SD (Stable Diffusion) are trained on very specific resolutions, its the fancier models that are trained on higher quality, or more diverse sets of resolutions, and if you use a higher quality model to generate lower resolution images, what's actually happening is you're trimming a much bigger image and getting a chunk of it output, at least that's how it feels based on my many hours of experimenting. If I use major models and try to center a thing, I never see it in the center. :) My GPU can only handle so much.
The general idea was: you mask the area you want changed, and the model inpaints that region at full resolution. The advantage of masking, compared to plain img2img, is that you’re not sending the entire picture to the model.
With the classic setups like SD 1.5 and SDXL, you’d effectively inpaint at full resolution: take the masked area from a larger image, scale just that region to the model’s native resolution, process it at the full ~1 megapixel then scale it back and composite it into the original. This lets you add MORE detail.
Unfortunately if the OP is using hosted SD models, they might not have that granular control and thus would suffer pretty bad quality loss.
The community made models (merges, fine tunes, etc) of that era are all completely overtrained and optimized for portraits and frontal shots. They would try to make a person out of anything. Inpainting faces is already a chore, even with a lot of tooling around that, but inpainting anything else is almost impossible. These models are also especially bad to fit objects naturally into scenes. You can make a crappy necklace or belt work, but introducing a new object into a scene just fails with infinite variety.
They are also much better using 512x512 as resolution, any larger deviation introduces more problems.
Considering you wanted to inpaint banner ads, they would probably get distorted heavily. Those models can't deal with fonts and are bad at a pixel perfect transfers. The only viable way to do this, at that time, would be to manually insert the banner ads and fix the seams with AI. Requires some artistic skill of course.
Your attempt was bold, but with the expectation of just supplying two images and let the models do it, it was impossible.
Also, what's going on behind the in-painted corner of the house? We'd need to see higher resolution pictures, but I'm not convinced that it too shouldn't get a flag. Likewise with the beach just behind the surfboard. Not terrible, but what gets flagged in the competitors is similar.
I have a potential project for my e-commerce where I want to allow users to upload images of their house exteriors and impaint awnings.
I have an example of interior decorating inpainting where I replaced a large floor-to-ceiling window with a mirror, and the result was pretty impressive using NB Pro from nearly a year ago.
Locally hostable? For my money I'd argue Flux.2 Klein but Qwen-Edit still puts in the work.
I do agree, however, that the Flux2 family is the SoTA at the moment. Running locally via something like Comfy gets incredible results.
So you're saying that, if I can calculate from the picture the position (height, inclination and such), and I can render the model (should be doable) for that height and angle, my best course of action could be to combine original + render and only at the end use a visual model? That could be interesting.
Note that I'm actively messing with it, so it may break for short periods of time :)
It's also running on the free CPU, so it's like 80 seconds per image...
Edit: I think I found it https://huggingface.co/hustvl/Moebius
Instead, you're supposed to upload it to the cloud and ask a big, multimodal frontier model to maybe please do the thing you want and nothing else.
https://characterdesignreferences.com/artist-of-the-week-3/m...
2) If these are reasonable, a WebGPU demo would be great..
Barely useful enough to erase things in thumbnails.
Is it just me or is it weird seeing these clickbaity AI-generated taglines in an otherwise scientific work?
Apart from this, the text details amazing work. Congrats.
I think it is safe to say this is pretty far from a "scientific" work.