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arXiv · 2104.07905

Ego-Exo: Transferring Visual Representations from Third-person to First-person Videos

Yanghao Li·Tushar Nagarajan·Bo Xiong·Kristen Grauman
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Abstract

We introduce an approach for pre-training egocentric video models using large-scale third-person video datasets. Learning from purely egocentric data is limited by low dataset scale and diversity, while using purely exocentric (third-person) data introduces a large domain mismatch. Our idea is to discover latent signals in third-person video that are predictive of key egocentric-specific properties. Incorporating these signals as knowledge distillation losses during pre-training results in models that benefit from both the scale and diversity of third-person video data, as well as representations that capture salient egocentric properties. Our experiments show that our Ego-Exo framework can be seamlessly integrated into standard video models; it outperforms all baselines when fine-tuned for egocentric activity recognition, achieving state-of-the-art results on Charades-Ego and EPIC-Kitchens-100.

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Yanghao Li, Tushar Nagarajan, Bo Xiong, Kristen Grauman. 2021-04-16. Ego-Exo: Transferring Visual Representations from Third-person to First-person Videos. https://arxiv.org/abs/2104.07905

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