Entropic Descent Archetypal Analysis for Blind Hyperspectral Unmixing

Alexandre Zouaoui (1) , Gedeon Muhawenayo (1) , Behnood Rasti (2) , Jocelyn Chanussot (1) , Julien Mairal (1)

1 Thoth - Apprentissage de modèles à partir de données massives
2 HZDR - Helmholtz-Zentrum Dresden-Rossendorf

In this paper, we introduce a new algorithm based on archetypal analysis for blind hyperspectral unmixing, assuming linear mixing of endmembers. Archetypal analysis is a natural formulation for this task. This method does not require the presence of pure pixels (i.e., pixels containing a single material) but instead represents endmembers as convex combinations of a few pixels present in the original hyperspectral image. Our approach leverages an entropic gradient descent strategy, which (i) provides better solutions for hyperspectral unmixing than traditional archetypal analysis algorithms, and (ii) leads to efficient GPU implementations. Since running a single instance of our algorithm is fast, we also propose an ensembling mechanism along with an appropriate model selection procedure that make our method robust to hyper-parameter choices while keeping the computational complexity reasonable. By using six standard real datasets, we show that our approach outperforms stateof-the-art matrix factorization and recent deep learning methods. We also provide an open-source PyTorch implementation: https://github.com/inria-thoth/EDAA.

Keywords: Hyperspectral image; remote sensing; blind spectral unmixing; non-negative matrix factorization; archetypal analysis; entropic gradient descent

Domains: Machine Learning [cs.LG]; Image Processing [eess.IV]; Computer Vision and Pattern Recognition [cs.CV]

Alexandre Zouaoui, Gedeon Muhawenayo, Behnood Rasti, Jocelyn Chanussot, Julien Mairal. Entropic Descent Archetypal Analysis for Blind Hyperspectral Unmixing. 2022. ⟨hal-03788427v1⟩