Github url


by open-mmlab

open-mmlab /mmdetection

OpenMMLab Detection Toolbox and Benchmark

10.6K Stars 3.6K Forks Last release: 5 days ago (v2.2.1) Apache License 2.0 1.1K Commits 12 Releases

Available items

No Items, yet!

The developer of this repository has not created any items for sale yet. Need a bug fixed? Help with integration? A different license? Create a request here:

News: We released the technical report on ArXiv.



MMDetection is an open source object detection toolbox based on PyTorch. It is a part of the OpenMMLab project developed by Multimedia Laboratory, CUHK.

The master branch works with PyTorch 1.3 to 1.5. The old v1.x branch works with PyTorch 1.1 to 1.4, but v2.0 is strongly recommended for faster speed, higher performance, better design and more friendly usage.

demo image

Major features

  • Modular Design

We decompose the detection framework into different components and one can easily construct a customized object detection framework by combining different modules.

  • Support of multiple frameworks out of box

The toolbox directly supports popular and contemporary detection frameworks, e.g. Faster RCNN, Mask RCNN, RetinaNet, etc.

  • High efficiency

All basic bbox and mask operations run on GPUs. The training speed is faster than or comparable to other codebases, including Detectron2, maskrcnn-benchmark and SimpleDet.

  • State of the art

The toolbox stems from the codebase developed by the MMDet team, who won COCO Detection Challenge in 2018, and we keep pushing it forward.

Apart from MMDetection, we also released a library mmcv for computer vision research, which is heavily depended on by this toolbox.


This project is released under the Apache 2.0 license.


v2.2.0 was released in 1/7/2020. Please refer to for details and release history. A comparison between v1.x and v2.0 codebases can be found in

Benchmark and model zoo

Results and models are available in the model zoo.

Supported backbones: - [x] ResNet - [x] ResNeXt - [x] VGG - [x] HRNet - [x] RegNet - [x] Res2Net

Supported methods: - [x] RPN- [x] Fast R-CNN- [x] Faster R-CNN- [x] Mask R-CNN- [x] Cascade R-CNN- [x] Cascade Mask R-CNN- [x] SSD- [x] RetinaNet- [x] GHM- [x] Mask Scoring R-CNN- [x] Double-Head R-CNN- [x] Hybrid Task Cascade- [x] Libra R-CNN- [x] Guided Anchoring- [x] FCOS- [x] RepPoints- [x] Foveabox- [x] FreeAnchor- [x] NAS-FPN- [x] ATSS- [x] FSAF- [x] PAFPN- [x] Dynamic R-CNN- [x] PointRend- [x] CARAFE- [x] DCNv2- [x] Group Normalization- [x] Weight Standardization- [x] OHEM- [x] Soft-NMS- [x] Generalized Attention- [x] GCNet- [x] Mixed Precision (FP16) Training- [x] InstaBoost- [x] GRoIE- [x] DetectoRS- [x] Generalized Focal Loss

Some other methods are also supported in projects using MMDetection.


Please refer to for installation and dataset preparation.

Getting Started

Please see for the basic usage of MMDetection. There are also tutorials for finetuning models, adding new dataset, designing data pipeline, and adding new modules.


We appreciate all contributions to improve MMDetection. Please refer to for the contributing guideline.


MMDetection is an open source project that is contributed by researchers and engineers from various colleges and companies. We appreciate all the contributors who implement their methods or add new features, as well as users who give valuable feedbacks. We wish that the toolbox and benchmark could serve the growing research community by providing a flexible toolkit to reimplement existing methods and develop their own new detectors.


If you use this toolbox or benchmark in your research, please cite this project.

@article{mmdetection, title = {{MMDetection}: Open MMLab Detection Toolbox and Benchmark}, author = {Chen, Kai and Wang, Jiaqi and Pang, Jiangmiao and Cao, Yuhang and Xiong, Yu and Li, Xiaoxiao and Sun, Shuyang and Feng, Wansen and Liu, Ziwei and Xu, Jiarui and Zhang, Zheng and Cheng, Dazhi and Zhu, Chenchen and Cheng, Tianheng and Zhao, Qijie and Li, Buyu and Lu, Xin and Zhu, Rui and Wu, Yue and Dai, Jifeng and Wang, Jingdong and Shi, Jianping and Ouyang, Wanli and Loy, Chen Change and Lin, Dahua}, journal= {arXiv preprint arXiv:1906.07155}, year={2019} }


This repo is currently maintained by Kai Chen (@hellock), Yuhang Cao (@yhcao6), Wenwei Zhang (@ZwwWayne), Jiarui Xu (@xvjiarui). Other core developers include Jiangmiao Pang (@OceanPang) and Jiaqi Wang (@myownskyW7).

We use cookies. If you continue to browse the site, you agree to the use of cookies. For more information on our use of cookies please see our Privacy Policy.