# SegFormer (b5-sized) encoder pre-trained-only

SegFormer encoder fine-tuned on Imagenet-1k. It was introduced in the paper SegFormer: Simple and Efficient Design for Semantic Segmentation with Transformers by Xie et al. and first released in this repository.

Disclaimer: The team releasing SegFormer did not write a model card for this model so this model card has been written by the Hugging Face team.

## Model description

SegFormer consists of a hierarchical Transformer encoder and a lightweight all-MLP decode head to achieve great results on semantic segmentation benchmarks such as ADE20K and Cityscapes. The hierarchical Transformer is first pre-trained on ImageNet-1k, after which a decode head is added and fine-tuned altogether on a downstream dataset.

This repository only contains the pre-trained hierarchical Transformer, hence it can be used for fine-tuning purposes.

## Intended uses & limitations

You can use the model for fine-tuning of semantic segmentation. See the model hub to look for fine-tuned versions on a task that interests you.

### How to use

Here is how to use this model to classify an image of the COCO 2017 dataset into one of the 1,000 ImageNet classes:

from transformers import SegformerFeatureExtractor, SegformerForImageClassification
from PIL import Image
import requests

url = "http://images.cocodataset.org/val2017/000000039769.jpg"
image = Image.open(requests.get(url, stream=True).raw)

feature_extractor = SegformerFeatureExtractor.from_pretrained("nvidia/mit-b5")
model = SegformerForImageClassification.from_pretrained("nvidia/mit-b5")

inputs = feature_extractor(images=image, return_tensors="pt")
outputs = model(**inputs)
logits = outputs.logits
# model predicts one of the 1000 ImageNet classes
predicted_class_idx = logits.argmax(-1).item()
print("Predicted class:", model.config.id2label[predicted_class_idx])


For more code examples, we refer to the documentation.

The license for this model can be found here.

### BibTeX entry and citation info

@article{DBLP:journals/corr/abs-2105-15203,
author    = {Enze Xie and
Wenhai Wang and
Zhiding Yu and
Anima Anandkumar and
Jose M. Alvarez and
Ping Luo},
title     = {SegFormer: Simple and Efficient Design for Semantic Segmentation with
Transformers},
journal   = {CoRR},
volume    = {abs/2105.15203},
year      = {2021},
url       = {https://arxiv.org/abs/2105.15203},
eprinttype = {arXiv},
eprint    = {2105.15203},
timestamp = {Wed, 02 Jun 2021 11:46:42 +0200},
biburl    = {https://dblp.org/rec/journals/corr/abs-2105-15203.bib},
bibsource = {dblp computer science bibliography, https://dblp.org}
}