facebookresearch/SlowFast

PySlowFast: video understanding codebase from FAIR for reproducing state-of-the-art video models.

Python

7,428

161 commits

updated Mar 16, 2026

See the code

README

PySlowFast

PySlowFast is an open source video understanding codebase from FAIR that provides state-of-the-art video classification models with efficient training. This repository includes implementations of the following methods:

Introduction

The goal of PySlowFast is to provide a high-performance, light-weight pytorch codebase provides state-of-the-art video backbones for video understanding research on different tasks (classification, detection, and etc). It is designed in order to support rapid implementation and evaluation of novel video research ideas. PySlowFast includes implementations of the following backbone network architectures:

  • SlowFast
  • Slow
  • C2D
  • I3D
  • Non-local Network
  • X3D
  • MViTv1 and MViTv2
  • Rev-ViT and Rev-MViT

Updates

License

PySlowFast is released under the Apache 2.0 license.

Model Zoo and Baselines

We provide a large set of baseline results and trained models available for download in the PySlowFast Model Zoo.

Installation

Please find installation instructions for PyTorch and PySlowFast in INSTALL.md. You may follow the instructions in DATASET.md to prepare the datasets.

Quick Start

Follow the example in GETTING_STARTED.md to start playing video models with PySlowFast.

Visualization Tools

We offer a range of visualization tools for the train/eval/test processes, model analysis, and for running inference with trained model. More information at Visualization Tools.

Contributors

PySlowFast is written and maintained by Haoqi Fan, Yanghao Li, Bo Xiong, Wan-Yen Lo, Christoph Feichtenhofer.

Citing PySlowFast

If you find PySlowFast useful in your research, please use the following BibTeX entry for citation.

@misc{fan2020pyslowfast,
  author =       {Haoqi Fan and Yanghao Li and Bo Xiong and Wan-Yen Lo and
                  Christoph Feichtenhofer},
  title =        {PySlowFast},
  howpublished = {\url{https://github.com/facebookresearch/slowfast}},
  year =         {2020}
}

Significant stargazers

Cheney Zhang

143 followers · starred Mar 2022

Siyuan Li

83 followers · starred Feb 2023

Tomu Hirata

88 followers · starred Nov 2020

Kirill Bobyrev

138 followers · starred Nov 2025

facebookresearch/SlowFast

PySlowFast: video understanding codebase from FAIR for reproducing state-of-the-art video models.

Python

7,428

161 commits

updated Mar 16, 2026

See the code

README

PySlowFast

PySlowFast is an open source video understanding codebase from FAIR that provides state-of-the-art video classification models with efficient training. This repository includes implementations of the following methods:

Introduction

The goal of PySlowFast is to provide a high-performance, light-weight pytorch codebase provides state-of-the-art video backbones for video understanding research on different tasks (classification, detection, and etc). It is designed in order to support rapid implementation and evaluation of novel video research ideas. PySlowFast includes implementations of the following backbone network architectures:

  • SlowFast
  • Slow
  • C2D
  • I3D
  • Non-local Network
  • X3D
  • MViTv1 and MViTv2
  • Rev-ViT and Rev-MViT

Updates

License

PySlowFast is released under the Apache 2.0 license.

Model Zoo and Baselines

We provide a large set of baseline results and trained models available for download in the PySlowFast Model Zoo.

Installation

Please find installation instructions for PyTorch and PySlowFast in INSTALL.md. You may follow the instructions in DATASET.md to prepare the datasets.

Quick Start

Follow the example in GETTING_STARTED.md to start playing video models with PySlowFast.

Visualization Tools

We offer a range of visualization tools for the train/eval/test processes, model analysis, and for running inference with trained model. More information at Visualization Tools.

Contributors

PySlowFast is written and maintained by Haoqi Fan, Yanghao Li, Bo Xiong, Wan-Yen Lo, Christoph Feichtenhofer.

Citing PySlowFast

If you find PySlowFast useful in your research, please use the following BibTeX entry for citation.

@misc{fan2020pyslowfast,
  author =       {Haoqi Fan and Yanghao Li and Bo Xiong and Wan-Yen Lo and
                  Christoph Feichtenhofer},
  title =        {PySlowFast},
  howpublished = {\url{https://github.com/facebookresearch/slowfast}},
  year =         {2020}
}

Significant stargazers

Cheney Zhang

143 followers · starred Mar 2022

Siyuan Li

83 followers · starred Feb 2023

Tomu Hirata

88 followers · starred Nov 2020

Kirill Bobyrev

138 followers · starred Nov 2025