alt.hn

7/27/2026 at 4:59:08 PM

Show HN: FeyNoBg – Automatic background removal model and training library

 https://usefeyn.com/blog/feynobg/

by snyy

7/27/2026 at 6:24:00 PM

I love seeing this. Background removal is such a core task used in so many systems, I group it in with speech to text in terms of importance.

I love seeing maturity getting pushed in this space. Congratulations to you and the team!

by geooff_

7/27/2026 at 7:59:22 PM

Why extend an MIT licensed model's weights (BiRefNet) and release it under a cc-by-nc-4.0 license?

by woadwarrior01

7/27/2026 at 8:40:37 PM

This pertains to the larger open source licensing discussions that have been happening (as I'm sure you've seen too).

We've released projects under the MIT license before, most notably https://github.com/feyninc/chonkie. While we're not trying to directly monetize on this work, credit goes a long way and helps in other operations.

Recently, attributed usage is shrinking. To be clear, this is not a shrinkage in actual use of our software, just how many people acknowledge that they rely on it.

cc-by-nc is a protection against that. We've been very honest about our work being on top of BiRefNet as we want to extend the original creators the same courtesy. I have no issues if individuals fork/finetune/or otherwise build on top of any open source projects we release, irrespective of license. At minimum, we want acknowledgment if a company chooses to use our software in production.

by snyy

7/28/2026 at 7:11:48 AM

> cc-by-nc is a protection against that.

I don’t think so. There are CC licenses that allow for commercial usage. Most companies ban their developers from using anything with an NC or GPL style licence (with an exception for the Linux kernel).

Also, you might want to speak to an IP lawyer about the legality of re-licensing a derivative of an MIT licensed work, without attribution.

by woadwarrior01

7/28/2026 at 7:48:09 AM

Hi, thanks a lot for bringing this to our radar, and i have updated the model card to reflect this change, and i will update the library shortly to enforce this choice of license. I have provided additional information in the same thread above, and will reach out to the original author shortly with an apology and I will see how it goes. I would also like to apologise to the community and i will do better in the future. - Hafedh Hichri (Lain)

by not_lain

7/28/2026 at 11:31:46 AM

Hey, thanks for doing the right thing. There's no need for an apology.

by woadwarrior01

7/28/2026 at 7:40:07 AM

I did reach out to Peng (the original author) before the release about license, citation, paper_url with specific emphasis on the the license part and got the green light from him to release the model under the original MIT license or the apache2.0 license since i have pushed for it. since this is a mistake from my part not iterating with the team about my comms i sincerely apologize for this and I have updated the model card to reflect this change to use the original MIT license, i will also update the library so that all models using the birefnet architecture will be released under the MIT license shortly. and thanks a lot for bringing this to my radar.

by not_lain

7/27/2026 at 8:37:51 PM

Yep, nobody wants to adopt models with this license because it opens legal questions most users, whether professional or non-professional, don't want to muddy their work with.

by popalchemist

7/27/2026 at 6:11:34 PM

This looks great! What are the resolution limits? From the GitHub readme I saw mention of 1024x1024, but I was able to process an image 1920x2880 just fine. I didn't see any really obvious scaling artefacts, so is there something clever happening behind the scenes?

by nickludlam

7/27/2026 at 6:26:14 PM

We resize the opacity mask. That tends to scale better

by snyy

7/27/2026 at 9:23:23 PM

How does it stack up against Adobe's model? The advantage Adobe has is there are essentially two options: (1) Select Subject (95% of the time will give you the result you want); (2) Select Person (helps in the edge cases).

The issue I have is, what is the subject? For instance, you have a person sat on a couch. You hit Select Subject. Is the subject the person, or the person plus the couch?

With Adobe's when I only want the person, most of the time Select Subject works, and when it doesn't I can pivot to Select Person, but that has its own problem because it won't include props that the subject is holding, only the person and their clothing.

by qingcharles

7/27/2026 at 9:37:03 PM

Your question touches on excellent points.

> what is the subject?

FeyNoBg is an "automatic" model. It automatically detects foreground elements and segments the image. Most of the time, this includes all foreground elements. As you can see in the freekick example (https://drive.google.com/file/d/1MZkAGLwbhNVOZ0Oi7XvpCfSEu9Q...), the model output includes the ball, Messi, and the Liverpool defenders. In your example, FeyNoBg will segment around the person plus the couch.

> I only want the person [including props]

The alternative to automatic models are prompt models and those serve the exact use case you're describing. These allow you to specify the foreground element to include. Everything else is removed. That's the next step for FeyNoBg, converting it from an automatic to a prompt model. Now, answering your question:

> How does it stack up against Adobe's model?

We're better on automatic background removal. Support for selecting a subset of foreground elements is coming soon

by snyy

7/27/2026 at 10:11:11 PM

Thank you for the excellent reply.

by qingcharles

7/27/2026 at 9:36:50 PM

I'd be very interested in that, too.

by janrakete

7/27/2026 at 6:13:29 PM

This is awesome, I just bookmarked your tool. Ive been looking for something simple to use, since Its not easy to use the segment anything tool anymore. Thanks!

by defmetrix

7/27/2026 at 6:51:52 PM

I was so impressed with remove.bg in Dec 2018; awesome to see the progress in this area, so cool.

by yarone

7/28/2026 at 11:50:13 AM

For causal use, I've had best success with freemium photoroom.com (export res limit on free use). Even better than OP's, but it's been a while since I've compared these.

by filcuk

7/27/2026 at 9:21:17 PM

How did you assemble your training dataset, especially since you mention some of the considerations with different training mixes in your controlled eval?

by rahulb0802

7/27/2026 at 9:43:44 PM

Our blog covers this: https://usefeyn.com/blog/feynobg/#strength-in-diverse-data

Recapping here: Our first train was on 4,000 images from the MaskFactory dataset alone. This improved some benchmarks but regressed on others. We took this as a sign of narrow datasets causing unintended specialization.

In our next run, we assembled 26.1K images from 10 different datasets. We capped the amount of images that could come from one source, to prevent a single type of example from dominating. This composite set covered several cases like crowded scenes, camouflage, high-res subjects, fine objects like hair, blurred backgrounds, etc. We then shuffled everything together and trained FeyNoBg.

by snyy

7/29/2026 at 1:42:10 AM

congrats! do you guys focus on video as well?

by harrisontin

7/27/2026 at 6:31:22 PM

very cool! I've been having a fun time porting non-LLM models to iOS/Android (recently had some success with making Bonsai's image generation model run on Android) - have you attempted to run any of the workflows on a mobile device at all? Mind if I try?

by sudb

7/27/2026 at 6:36:39 PM

Please do try, I would love nothing more!

All I ask is you make a PR to https://github.com/feyninc/nobg with your results. We'd love to see what you make, contribute in any way we can, and share onwards.

by snyy

7/27/2026 at 6:45:25 PM

Of course, would be happy to!

by sudb

7/28/2026 at 10:19:50 AM

feynobg vs u2-net?

by terryXyz

7/29/2026 at 5:58:46 PM

[flagged]

by wittyurchin

7/28/2026 at 7:57:43 AM

[flagged]

by wayknow

7/28/2026 at 10:27:07 AM

[flagged]

by VaporJournalAPP

7/27/2026 at 5:44:08 PM

[flagged]

by bickov

7/27/2026 at 6:03:06 PM

The 4K cap was a judgement call, we didn't want one source to dominate. The license is cc-by-nc, just added it to the hugging face

by snyy