Self-Supervised Representation Learning for Cloud Detection Using Sentinel-2 images

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Overview

This repository provides the code that supports the paper Self-Supervised Representation Learning for Cloud Detection Using Sentinel-2 images published in Remote Sensing of Environment.

Authors: Yawogan Jean Eudes Gbodjo, Lloyd Haydn Hughes, Matthieu Molinier, Devis Tuia and Jun Li

View Our Paper

In this work, we examine the self-supervised learning paradigm using two computer vision frameworks namely MoCo (Momentum Contrast) and DeepCluster for the downstream task of cloud detection in Sentinel-2 multispectral images. A ResNet-18 backbone is used as encoder in both frameworks. MoCo and DeepCluster pretext tasks are respectively contrastive learning and clustering based. We pretrained MoCo using Sentinel-2 images from a generic land cover mapping dataset i.e. SEN12MS containing no cloudy observations. Unlike MoCo, DeepCluster pretraining consisted of learning to cluster Sentinel-2 image patches from cloud detection datasets namely WHUS2-CD+ and CloudSEN12 datasets. After pretraining, the ResNet-18 encoder is plugged with a segmentation head (4 layers: 3x3 Conv, Instance normalization, ReLU activation and 1x1 Conv) and the learned representations are fine-tuned to perform the cloud detection using various fractions of annotations. Obtained results on both WHUS2-CD+ and CloudSEN12 datasets show that the proposed methods surpassed industry standards (F-Mask, Sen2Cor), weakly supervised methods and even some fully supervised methods using only 25% of annotations for fine-tuning.

Getting started

This section will walk you through setting up the environment and running the code.

Installation

1. Clone the repository:

   git clone https://github.com/eudesyawog/self-supervised-cloud-detection.git
   cd self-supervised-cloud-detection

2. Install the dependencies:

   # Create a new environment e.g. a virtual environment
   python -m venv /path/to/new/virtual/environment
   source /path/to/new/virtual/environment/bin/activate 
   
   # Install all required packages
   pip install .

Dataset preprocessing

Download and uncompress the 3 datasets (SEN12MS, WHUS2-CD+ and CloudSEN12) into your local repository. Download links can be found in the respective Github repositories provided in the section Overview. Additionnaly, you will need to split the Sentinel-2 images of the WHUS2-CD+ dataset into (384 $\times$ 384) patches. To this end, use the code provided here.

Running the code

Examples are provided in the notebook pretraining.ipynb and finetuning.ipynb on how to perform pretraining and fine-tuning of MoCo and DeepCluster for cloud detection using the datasets.

Citation

If you use MoCo and DeepCluster for cloud detection in your research, please cite the paper:

@article{Gbodjo2026,
title = {Self-supervised representation learning for cloud detection using Sentinel-2 images},
author = {Yawogan Jean Eudes Gbodjo and Lloyd Haydn Hughes and Matthieu Molinier and Devis Tuia and Jun Li},
journal = {Remote Sensing of Environment},
volume = {334},
pages = {115205},
year = {2026},
issn = {0034-4257},
doi = {https://doi.org/10.1016/j.rse.2025.115205},
url = {https://www.sciencedirect.com/science/article/pii/S0034425725006091},
}

Contact

If you have any questions or feedback regarding the code, please feel free to reach out to jean-eudes[dot]gbodjo[at]vtt[dot]fi.