Learning Group Activities from Skeletons without Individual Action
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- URL: http://arxiv.org/abs/2105.06754v1
- Date: Fri, 14 May 2021 10:31:32 GMT
- Title: Learning Group Activities from Skeletons without Individual Action
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- Authors: Fabio Zappardino and Tiberio Uricchio and Lorenzo Seidenari and
Alberto Del Bimbo
- Abstract summary: We show that using only skeletal data we can train a state-of-the art end-to-end system using only group activity labels at the sequence level.
Our experiments show that models trained without individual action supervision perform poorly.
Our carefully designed lean pose only architecture shows highly competitive results versus more complex multimodal approaches even in the self-supervised variant.
- Score: 32.60526967706986
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: To understand human behavior we must not just recognize individual actions
but model possibly complex group activity and interactions. Hierarchical models
obtain the best results in group activity recognition but require fine grained
individual action annotations at the actor level. In this paper we show that
using only skeletal data we can train a state-of-the art end-to-end system
using only group activity labels at the sequence level. Our experiments show
that models trained without individual action supervision perform poorly. On
the other hand we show that pseudo-labels can be computed from any pre-trained
feature extractor with comparable final performance. Finally our carefully
designed lean pose only architecture shows highly competitive results versus
more complex multimodal approaches even in the self-supervised variant.
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