ServiceNow completed its acquisition of Element AI on January 8, 2021. All references to Element AI in the materials that are part of this project should refer to ServiceNow.

This is the official PyTorch implementation of the SeCo paper:

@article{manas2021seasonal,
  title={Seasonal Contrast: Unsupervised Pre-Training from Uncurated Remote Sensing Data},
  author={Ma{\~n}as, Oscar and Lacoste, Alexandre and Giro-i-Nieto, Xavier and Vazquez, David and Rodriguez, Pau},
  journal={arXiv preprint arXiv:2103.16607},
  year={2021}
}

Install Python dependencies by running:

pip install -r requirements.txt

First, obtain Earth Engine authentication credentials by following the installation instructions.

Then, to collect and download a new SeCo dataset from a random set of Earth locations, run:

python datasets/seco_downloader.py \
  --save_path [folder where data will be downloaded] \
  --num_locations 200000

To do unsupervised pre-training of a ResNet-18 model on the SeCo dataset, run:

python main_pretrain.py \
  --data_dir datasets/seco_1m --data_mode seco \
  --base_encoder resnet18

With a pre-trained SeCo model, to train a supervised linear classifier on 10% of the BigEarthNet training set in a 4-GPU machine, run:

python main_bigearthnet.py \
  --gpus 4 --accelerator dp --batch_size 1024 \
  --data_dir datasets/bigearthnet --train_frac 0.1 \
  --backbone_type pretrain --ckpt_path checkpoints/seco_resnet18_1m.ckpt \
  --freeze_backbone --learning_rate 1e-3

To train a supervised linear classifier on EuroSAT from a pre-trained SeCo model, run:

python main_eurosat.py \
  --data_dir datasets/eurosat \
  --backbone_type pretrain --ckpt_path checkpoints/seco_resnet18_1m.ckpt

To train a supervised change detection model on OSCD from a pre-trained SeCo model, run:

python main_oscd.py \
  --data_dir datasets/oscd \
  --backbone_type pretrain --ckpt_path checkpoints/seco_resnet18_1m.ckpt

Our collected SeCo datasets can be downloaded as following:

Our pre-trained SeCo models can be downloaded as following: