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arXiv · 1109.3827

Online Robust Subspace Tracking from Partial Information

Jun He·Laura Balzano·John C. S. Lui
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Abstract

This paper presents GRASTA (Grassmannian Robust Adaptive Subspace Tracking Algorithm), an efficient and robust online algorithm for tracking subspaces from highly incomplete information. The algorithm uses a robust $l^1$-norm cost function in order to estimate and track non-stationary subspaces when the streaming data vectors are corrupted with outliers. We apply GRASTA to the problems of robust matrix completion and real-time separation of background from foreground in video. In this second application, we show that GRASTA performs high-quality separation of moving objects from background at exceptional speeds: In one popular benchmark video example, GRASTA achieves a rate of 57 frames per second, even when run in MATLAB on a personal laptop.

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Jun He, Laura Balzano, John C. S. Lui. 2011-09-18. Online Robust Subspace Tracking from Partial Information. https://arxiv.org/abs/1109.3827

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