MViTv2: Improved Multiscale Vision Transformers for Classification and Detection

Official PyTorch implementation of MViTv2, from the following paper:

MViTv2: Improved Multiscale Vision Transformers for Classification and Detection. CVPR 2022.
Yanghao Li*, Chao-Yuan Wu*, Haoqi Fan, Karttikeya Mangalam, Bo Xiong, Jitendra Malik, Christoph Feichtenhofer*

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MViT is a multiscale transformer which serves as a general vision backbone for different visual recognition tasks:

Image Classification: Included in this repo.

Object Detection and Instance Segmentation: See MViTv2 in Detectron2.

Video Action Recognition and Detection: See MViTv2 in PySlowFast.

Results and Pre-trained Models

ImageNet-1K trained models

name	resolution	acc@1	#params	FLOPs	1k model
MViTv2-T	224x224	82.3	24M	4.7G	model
MViTv2-S	224x224	83.6	35M	7.0G	model
MViTv2-B	224x224	84.4	52M	10.2G	model
MViTv2-L	224x224	85.3	218M	42.1G	model

ImageNet-21K trained models

name	resolution	acc@1	#params	FLOPs	21k model	1k model
MViTv2-B	224x224	-	52M	10.2G	model	-
MViTv2-L	224x224	87.5	218M	42.1G	model	-
MViTv2-H	224x224	88.0	667M	120.6G	model	-

Installation

Please check INSTALL.md for installation instructions.

Training

Here we can train a standard MViTv2 model from scratch by:

python tools/main.py \
  --cfg configs/MViTv2_T.yaml \
  DATA.PATH_TO_DATA_DIR path_to_your_dataset \
  NUM_GPUS 8 \
  TRAIN.BATCH_SIZE 256 \

Evaluation

To evaluate a pretrained MViT model:

python tools/main.py \
  --cfg configs/test/MViTv2_T_test.yaml \
  DATA.PATH_TO_DATA_DIR path_to_your_dataset \
  NUM_GPUS 8 \
  TEST.BATCH_SIZE 256 \

Acknowledgement

This repository is built based on the PySlowFast.

License

MViT is released under the Apache 2.0 license.

Citation

If you find this repository helpful, please consider citing:

@inproceedings{li2021improved,
  title={MViTv2: Improved multiscale vision transformers for classification and detection},
  author={Li, Yanghao and Wu, Chao-Yuan and Fan, Haoqi and Mangalam, Karttikeya and Xiong, Bo and Malik, Jitendra and Feichtenhofer, Christoph},
  booktitle={CVPR},
  year={2022}
}

@inproceedings{fan2021multiscale,
  title={Multiscale vision transformers},
  author={Fan, Haoqi and Xiong, Bo and Mangalam, Karttikeya and Li, Yanghao and Yan, Zhicheng and Malik, Jitendra and Feichtenhofer, Christoph},
  booktitle={ICCV},
  year={2021}
}