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arXiv · 2304.12160

End-to-End Spatio-Temporal Action Localisation with Video Transformers

Alexey Gritsenko·Xuehan Xiong·Josip Djolonga·Mostafa Dehghani·Chen Sun·Mario Lučić·Cordelia Schmid·Anurag Arnab
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Abstract

The most performant spatio-temporal action localisation models use external person proposals and complex external memory banks. We propose a fully end-to-end, purely-transformer based model that directly ingests an input video, and outputs tubelets -- a sequence of bounding boxes and the action classes at each frame. Our flexible model can be trained with either sparse bounding-box supervision on individual frames, or full tubelet annotations. And in both cases, it predicts coherent tubelets as the output. Moreover, our end-to-end model requires no additional pre-processing in the form of proposals, or post-processing in terms of non-maximal suppression. We perform extensive ablation experiments, and significantly advance the state-of-the-art results on four different spatio-temporal action localisation benchmarks with both sparse keyframes and full tubelet annotations.

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Alexey Gritsenko, Xuehan Xiong, Josip Djolonga, Mostafa Dehghani, Chen Sun, Mario Lučić, Cordelia Schmid, Anurag Arnab. 2023-04-24. End-to-End Spatio-Temporal Action Localisation with Video Transformers. https://arxiv.org/abs/2304.12160

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