Unsupervised Pretraining with Region Priors for Object Detection

DETReg: Unsupervised Pretraining with Region Priors for Object Detection

Amir Bar, Xin Wang, Vadim Kantorov, Colorado J Reed, Roei Herzig, Gal Chechik, Anna Rohrbach, Trevor Darrell, Amir Globerson

Release

[x] COCO training code and eval - DONE
[x] Pretrained models - DONE
[ ] Pascal VOC training code and eval- TODO

Introduction

DETReg is an unsupervised pretraining approach for object DEtection with TRansformers using Region priors.
Motivated by the two tasks underlying object detection: localization and categorization, we combine two complementary signals for self-supervision. For an object localization signal, we use pseudo ground truth object bounding boxes from an off-the-shelf unsupervised region proposal method, Selective Search, which does not require training data and can detect objects at a high recall rate and very low precision.
The categorization signal comes from an object embedding loss that encourages invariant object representations, from which the object category can be inferred.
We show how to combine these two signals to train the Deformable DETR detection architecture from large amounts of unlabeled data. DETReg improves the performance over competitive baselines and previous self-supervised methods on standard benchmarks like MS COCO and PASCAL VOC. DETReg also outperforms previous supervised and unsupervised baseline approaches on low-data regime when trained with only 1%, 2%, 5%, and 10% of the labeled data on MS COCO.

Installation

Requirements

Linux, CUDA>=9.2, GCC>=5.4
Python>=3.7

We recommend you to use Anaconda to create a conda environment:
```
conda create -n detreg python=3.7 pip
```
Then, activate the environment:
```
conda activate detreg
```
Installation: (change cudatoolkit to your cuda version. For detailed pytorch installation instructions click here)
```
conda install pytorch==1.8.0 torchvision==0.9.0 torchaudio==0.8.0 cudatoolkit=10.2 -c pytorch
```
Other requirements
```
pip install -r requirements.txt
```

Compiling CUDA operators

cd ./models/ops
sh ./make.sh
# unit test (should see all checking is True)
python test.py

Usage

Dataset preparation

Please download COCO 2017 dataset and ImageNet and organize them as following:

code_root/
└── data/
    ├── ilsvrc/
          ├── train/
          └── val/
    └── MSCoco/
        ├── train2017/
        ├── val2017/
        └── annotations/
        	├── instances_train2017.json
        	└── instances_val2017.json

Note that in this work we used the ImageNet100 dataset, which is x10 smaller than ImageNet. To create ImageNet100 run the following command:

mkdir -p data/ilsvrc100/train
mkdir -p data/ilsvrc100/val
while read line; do ln -s <code_root>/data/ilsvrc/train/$line <code_root>/data/ilsvrc100/train/$line; done < <code_root>/datasets/category.txt
while read line; do ln -s <code_root>/data/ilsvrc/val/$line <code_root>/data/ilsvrc100/val/$line; done < <code_root>/datasets/category.txt

This should results with the following structure:

code_root/
└── data/
    ├── ilsvrc/
          ├── train/
          └── val/
    ├── ilsvrc100/
          ├── train/
          └── val/
    └── MSCoco/
        ├── train2017/
        ├── val2017/
        └── annotations/
        	├── instances_train2017.json
        	└── instances_val2017.json

Create ImageNet Selective Search boxes:

Download the precomputed ImageNet boxes and extract in the cache folder:

mkdir -p <code_root>/cache/ilsvrc && cd <code_root>/cache/ilsvrc 
wget https://github.com/amirbar/DETReg/releases/download/1.0.0/ss_box_cache.tar.gz
tar -xf ss_box_cache.tar.gz

Alternatively, you can compute Selective Search boxes yourself:

To create selective search boxes for ImageNet100 on a single machine, run the following command (set num_processes):

python -m datasets.cache_ss --dataset imagenet100 --part 0 --num_m 1 --num_p <num_processes_to_use>

To speed up the creation of boxes, change the arguments accordingly and run the following command on each different machine:

python -m datasets.cache_ss --dataset imagenet100 --part <machine_number> --num_m <num_machines> --num_p <num_processes_to_use>

The cached boxes are saved in the following structure:

code_root/
└── cache/
    └── ilsvrc/

Training

The command for pretraining DETReg on 8 GPUs on ImageNet100 is as following:

GPUS_PER_NODE=8 ./tools/run_dist_launch.sh 8 ./configs/DETReg_top30_in100.sh --batch_size 24 --num_workers 8

Training takes around 1.5 days with 8 NVIDIA V100 GPUs, you can download a pretrained model (see below) if you want to skip this step.

After pretraining, a checkpoint is saved in exps/DETReg_top30_in100/checkpoint.pth. To fine tune it over different coco settings use the following commands:
Fine tuning on full COCO (should take 2 days with 8 NVIDIA V100 GPUs):

GPUS_PER_NODE=8 ./tools/run_dist_launch.sh 8 ./configs/DETReg_fine_tune_full_coco.sh

For smaller subsets which trains faster, you can use smaller number of gpus (e.g 4 with batch size 2)/
Fine tuning on 1%

GPUS_PER_NODE=4 ./tools/run_dist_launch.sh 4 ./configs/DETReg_fine_tune_1pct_coco.sh --batch_size 2

Fine tuning on 2%

GPUS_PER_NODE=4 ./tools/run_dist_launch.sh 4 ./configs/DETReg_fine_tune_2pct_coco.sh --batch_size 2

Fine tuning on 5%

GPUS_PER_NODE=4 ./tools/run_dist_launch.sh 4 ./configs/DETReg_fine_tune_5pct_coco.sh --batch_size 2

Fine tuning on 10%

GPUS_PER_NODE=4 ./tools/run_dist_launch.sh 4 ./configs/DETReg_fine_tune_10pct_coco.sh --batch_size 2

Evaluation

To evaluate a finetuned model, use the following command from the project basedir:

./configs/<config file>.sh --resume exps/<config file>/checkpoint.pth --eval

Pretrained Models

Cite

If you found this code helpful, feel free to cite our work:

@misc{bar2021detreg,
      title={DETReg: Unsupervised Pretraining with Region Priors for Object Detection},
      author={Amir Bar and Xin Wang and Vadim Kantorov and Colorado J Reed and Roei Herzig and Gal Chechik and Anna Rohrbach and Trevor Darrell and Amir Globerson},
      year={2021},
      eprint={2106.04550},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}