đ UNI: Pretrained Vision Encoder for Histopathology
UNI is the largest pretrained vision encoder for histopathology, offering state - of - the - art performance across 34 clinical tasks. It provides strong performance gains on rare and underrepresented cancer types, and is publicly available for academic research.
đ Quick Start
Updates
UNI2, a successor to UNI, trained on over 200 million images from over 350k diverse H&E and IHC slides has been released! Model weights and instructions are available at: [[Huggingface Repo](https://huggingface.co/MahmoodLab/UNI2 - h)]
Model Card Links
[[Journal Link](https://www.nature.com/articles/s41591 - 024 - 02857 - 3)] | [Open Access Read Link] | [Github Repo] | [Cite]
⨠Features
What is UNI?
UNI is the largest pretrained vision encoder for histopathology (100M images, 100K WSIs) developed on internal neoplastic, infectious, inflamatory and normal tissue and also made publicly available. It shows state - of - the - art performance across 34 clinical tasks, with strong performance gains on rare and underrepresented cancer types.
- Why use UNI?: UNI does not use open datasets and large public histology slide collections (TCGA, CPTAC, PAIP, CAMELYON, PANDA, and others in TCIA) for pretraining, which are routinely used in benchmark development in computational pathology. This makes it suitable for building and evaluating pathology AI models without the risk of data contamination on public benchmarks or private histopathology slide collections.
Requesting Access
As mentioned in the gated prompt, you must agree to the outlined terms of use, with the primary email for your HuggingFace account matching your institutional email. If your primary email is a personal email (@gmail/@hotmail/@qq), your request will be denied. To fix this, you can: (1) add your official institutional email to your HF account, and confirm your email address to verify, and (2) set your institutional email as your primary email in your HF account. Other reasons for your request access being denied include other mistakes in the form submitted, for example: full name includes abbreviations, affiliation is not spelled out, the described research use is not sufficient, or email domain address not recognized.
đĻ Installation
Software Dependencies
Python Packages
- torch>=2.0: https://pytorch.org
- xformers>=0.0.18: https://github.com/facebookresearch/xformers
- timm>=0.9.8: https://github.com/huggingface/pytorch - image - models
Repositories
- DINOv2 (self - supervised learning): https://github.com/facebookresearch/dinov2
- CLAM (slide classification): https://github.com/mahmoodlab/CLAM
- Mask2Former (cell and tissue segmentation): https://github.com/facebookresearch/Mask2Former
- ViT - Adapter (cell and tissue segmentation): https://github.com/czczup/ViT - Adapter
- LGSSL (Linear Probe & Few - Shot Eval): https://github.com/mbanani/lgssl
đģ Usage Examples
Feature Extraction
Basic Usage
import timm
from timm.data import resolve_data_config
from timm.data.transforms_factory import create_transform
from huggingface_hub import login
login()
model = timm.create_model("hf - hub:MahmoodLab/uni", pretrained=True, init_values=1e - 5, dynamic_img_size=True)
transform = create_transform(**resolve_data_config(model.pretrained_cfg, model=model))
model.eval()
Advanced Usage
import os
import torch
from torchvision import transforms
import timm
from huggingface_hub import login, hf_hub_download
login()
local_dir = "../assets/ckpts/vit_large_patch16_224.dinov2.uni_mass100k/"
os.makedirs(local_dir, exist_ok=True)
hf_hub_download("MahmoodLab/UNI", filename="pytorch_model.bin", local_dir=local_dir, force_download=True)
model = timm.create_model(
"vit_large_patch16_224", img_size=224, patch_size=16, init_values=1e - 5, num_classes=0, dynamic_img_size=True
)
model.load_state_dict(torch.load(os.path.join(local_dir, "pytorch_model.bin"), map_location="cpu"), strict=True)
transform = transforms.Compose(
[
transforms.Resize(224),
transforms.ToTensor(),
transforms.Normalize(mean=(0.485, 0.456, 0.406), std=(0.229, 0.224, 0.225)),
]
)
model.eval()
Feature Extraction from Histopathology ROIs
from PIL import Image
image = Image.open("uni.jpg")
image = transform(image).unsqueeze(dim=0)
with torch.inference_mode():
feature_emb = model(image)
These pre - extracted features can then be used for ROI classification (via linear probing), slide classification (via multiple instance learning), and other machine learning settings.
Direct Use (with Pre - Extracted and Frozen Features)
The models can be used without fine - tuning to obtain competitive results on:
- ROI classification, with logistic regression classifiers applied on the class token.
- ROI classification, with k - nearest neighbors (k - NN) classifiers applied on the class token.
- ROI classification, with nearest centroid classifiers (SimpleShot) applied on the class token.
- ROI retrieval, using nearest neighbors classifiers
- slide classification, with multiple instance learning (MIL) classifiers applied on a bag of class tokens extracted from the WSI
Downstream Use (Finetuning)
It is also possible to perform fine - tuning on the models, and recommended for competitive performance on segmentation tasks. We recommend finetuning using frameworks specialized for adapting ViTs for dense prediction tasks, such as ViTDet or ViT - Adapter (which depends on Mask2Former).
đ Documentation
Model Description
Property |
Details |
Developed by |
Mahmood Lab AI for Pathology @ Harvard/BWH |
Model Type |
Pretrained vision backbone (ViT - L/16 via DINOv2) for multi - purpose evaluation on histopathology images |
Pretraining dataset |
Mass - 100K, sourced from private histology collections (BWH / MGH), in addition to slides from the public GTEx consortium. |
Repository |
https://github.com/mahmoodlab/UNI |
Paper |
https://www.nature.com/articles/s41591 - 024 - 02857 - 3 |
License |
CC - BY - NC - ND - 4.0 |
Training Details
- Training data: Mass - 100K, a pretraining dataset (sourced from MGH, BWH, and GTEx) composed of 75,832,905 [256Ã256] and 24,297,995 [512Ã512] histology images at 20Ã resolution, sampled from 100,402 H&E WSIs (100,130,900 images in total).
- Training regime: fp16 using PyTorch - FSDP mixed - precision.
- Training objective: DINOv2 SSL recipe with the following losses:
- DINO self - distillation loss with multi - crop
- iBOT masked - image modeling loss
- KoLeo regularization on [CLS] tokens
- Training length: 125,000 iterations with a batch size of 3072
- Model architecture: ViT - Large (0.3B params): Patch size 16, embedding dimension 1024, 16 heads, MLP FFN
- Hardware used: 4x8 Nvidia A100 80GB
- Hours trained: Approx 1024 GPU hours (32 hours total)
- Cloud provider: MGB ERIS Research Computing Core
đ License
This model and associated code are released under the CC - BY - NC - ND 4.0 license and may only be used for non - commercial, academic research purposes with proper attribution. Any commercial use, sale, or other monetization of the UNI model and its derivatives, which include models trained on outputs from the UNI model or datasets created from the UNI model, is prohibited and requires prior approval. Downloading the model requires prior registration on Hugging Face and agreeing to the terms of use. By downloading this model, you agree not to distribute, publish or reproduce a copy of the model. If another user within your organization wishes to use the UNI model, they must register as an individual user and agree to comply with the terms of use. Users may not attempt to re - identify the de - identified data used to develop the underlying model. If you are a commercial entity, please contact the corresponding author.
Contact
For any additional questions or comments, contact Faisal Mahmood (faisalmahmood@bwh.harvard.edu
),
Richard J. Chen (richardchen@g.harvard.edu
),
Tong Ding (tong_ding@g.harvard.edu
),
or Ming Y. Lu (mlu16@bwh.harvard.edu
).
Acknowledgements
The project was built on top of amazing repositories such as [ViT](https://github.com/google - research/big_vision), DINOv2, LGSSL, and [Timm](https://github.com/huggingface/pytorch - image - models/) (ViT model implementation). We thank the authors and developers for their contribution.
BibTeX
If you found our work useful in your research, please consider citing our work at:
Chen, R.J., Ding, T., Lu, M.Y., Williamson, D.F.K., et al. Towards a general - purpose foundation model for computational pathology. Nat Med (2024). https://doi.org/10.1038/s41591 - 024 - 02857 - 3
@article{chen2024uni,
title={Towards a General - Purpose Foundation Model for Computational Pathology},
author={Chen, Richard J and Ding, Tong and Lu, Ming Y and Williamson, Drew FK and Jaume, Guillaume and Chen, Bowen and Zhang, Andrew and Shao, Daniel and Song, Andrew H and Shaban, Muhammad and others},
journal={Nature Medicine},
publisher={Nature Publishing Group},
year={2024}
}
Works that use UNI should also attribute ViT and DINOv2.