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*This model was released on 2022-06-02 and added to Hugging Face Transformers on 2023-06-20.*

# EfficientFormer

<div class="flex flex-wrap space-x-1">
<img alt="PyTorch" src="https://img.shields.io/badge/PyTorch-DE3412?style=flat&logo=pytorch&logoColor=white">
</div>

<Tip warning={true}>

This model is in maintenance mode only, we don't accept any new PRs changing its code.
If you run into any issues running this model, please reinstall the last version that supported this model: v4.40.2.
You can do so by running the following command: `pip install -U transformers==4.40.2`.

</Tip>

## Overview

The EfficientFormer model was proposed in [EfficientFormer: Vision Transformers at MobileNet Speed](https://huggingface.co/papers/2206.01191)
by Yanyu Li, Geng Yuan, Yang Wen, Eric Hu, Georgios Evangelidis, Sergey Tulyakov, Yanzhi Wang, Jian Ren.  EfficientFormer proposes a
dimension-consistent pure transformer that can be run on mobile devices for dense prediction tasks like image classification, object
detection and semantic segmentation.

The abstract from the paper is the following:

*Vision Transformers (ViT) have shown rapid progress in computer vision tasks, achieving promising results on various benchmarks.
However, due to the massive number of parameters and model design, e.g., attention mechanism, ViT-based models are generally
times slower than lightweight convolutional networks. Therefore, the deployment of ViT for real-time applications is particularly
challenging, especially on resource-constrained hardware such as mobile devices. Recent efforts try to reduce the computation
complexity of ViT through network architecture search or hybrid design with MobileNet block, yet the inference speed is still
unsatisfactory. This leads to an important question: can transformers run as fast as MobileNet while obtaining high performance?
To answer this, we first revisit the network architecture and operators used in ViT-based models and identify inefficient designs.
Then we introduce a dimension-consistent pure transformer (without MobileNet blocks) as a design paradigm.
Finally, we perform latency-driven slimming to get a series of final models dubbed EfficientFormer.
Extensive experiments show the superiority of EfficientFormer in performance and speed on mobile devices.
Our fastest model, EfficientFormer-L1, achieves 79.2% top-1 accuracy on ImageNet-1K with only 1.6 ms inference latency on
iPhone 12 (compiled with CoreML), which { runs as fast as MobileNetV2×1.4 (1.6 ms, 74.7% top-1),} and our largest model,
EfficientFormer-L7, obtains 83.3% accuracy with only 7.0 ms latency. Our work proves that properly designed transformers can
reach extremely low latency on mobile devices while maintaining high performance.*

This model was contributed by [novice03](https://huggingface.co/novice03) and [Bearnardd](https://huggingface.co/Bearnardd).
The original code can be found [here](https://github.com/snap-research/EfficientFormer).

## Documentation resources

- [Image classification task guide](../tasks/image_classification)

## EfficientFormerConfig

[[autodoc]] EfficientFormerConfig

## EfficientFormerImageProcessor

[[autodoc]] EfficientFormerImageProcessor
    - preprocess

## EfficientFormerModel

[[autodoc]] EfficientFormerModel
    - forward

## EfficientFormerForImageClassification

[[autodoc]] EfficientFormerForImageClassification
    - forward

## EfficientFormerForImageClassificationWithTeacher

[[autodoc]] EfficientFormerForImageClassificationWithTeacher
    - forward
