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arXiv · 1907.10837

Submission to ActivityNet Challenge 2019: Task B Spatio-temporal Action Localization

Chunfei Ma·Joonhyang Choi·Byeongwon Lee·Seungji Yang
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Abstract

This technical report present an overview of our system proposed for the spatio-temporal action localization(SAL) task in ActivityNet Challenge 2019. Unlike previous two-streams-based works, we focus on exploring the end-to-end trainable architecture using only RGB sequential images. To this end, we employ a previously proposed simple yet effective two-branches network called SlowFast Networks which is capable of capturing both short- and long-term spatiotemporal features. Moreover, to handle the severe class imbalance and overfitting problems, we propose a correlation-preserving data augmentation method and a random label subsampling method which have been proven to be able to reduce overfitting and improve the performance.

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Chunfei Ma, Joonhyang Choi, Byeongwon Lee, Seungji Yang. 2019-07-25. Submission to ActivityNet Challenge 2019: Task B Spatio-temporal Action Localization. https://arxiv.org/abs/1907.10837

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