Papers › Channel-wise Topology Refinement Graph Convolution for Skeleton-Based Action Recognition

Channel-wise Topology Refinement Graph Convolution for Skeleton-Based Action Recognition

26 Jul 2021ICCV 2021 10arXiv:2107.12213archive 2025-07-28

Yuxin Chen, Ziqi Zhang, Chunfeng Yuan, Bing Li, Ying Deng, Weiming Hu

Graph convolutional networks (GCNs) have been widely used and achieved remarkable results in skeleton-based action recognition. In GCNs, graph topology dominates feature aggregation and therefore is the key to extracting representative features. In this work, we propose a novel Channel-wise Topology Refinement Graph Convolution (CTR-GC) to dynamically learn different topologies and effectively aggregate joint features in different channels for skeleton-based action recognition. The proposed CTR-GC models channel-wise topologies through learning a shared topology as a generic prior for all channels and refining it with channel-specific correlations for each channel. Our refinement method introduces few extra parameters and significantly reduces the difficulty of modeling channel-wise topologies. Furthermore, via reformulating graph convolutions into a unified form, we find that CTR-GC relaxes strict constraints of graph convolutions, leading to stronger representation capability. Combining CTR-GC with temporal modeling modules, we develop a powerful graph convolutional network named CTR-GCN which notably outperforms state-of-the-art methods on the NTU RGB+D, NTU RGB+D 120, and NW-UCLA datasets.

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Uason-Chen/CTR-GCN officialmentioned in papermentioned on GitHubpytorch report
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CTRGC Uason-Chen/CTR-GCN/model/ctrgcn.py official repository ran · metamorphic tier: deterministic licence not identified · pointer only · d7d10dd15822d04b · report
bn_init Uason-Chen/CTR-GCN/model/ctrgcn.py official repository unverified licence not identified · pointer only · da94160ed9fd5926 · report
conv_init Uason-Chen/CTR-GCN/model/ctrgcn.py official repository unverified licence not identified · pointer only · 0f3bc22a15a9d724 · report
CTRGC kennymckormick/pyskl/pyskl/models/gcns/utils/gcn.py community (archive-listed) ran fingerprinted Apache-2.0 (permissive) · a6e280c955a92cc1 · report
conv_init kennymckormick/pyskl/pyskl/models/gcns/utils/gcn.py community (archive-listed) unverified Apache-2.0 (permissive) · a3ca5080ddd9c2fc · report

Tasks

Action RecognitionSkeleton Based Action Recognition

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Skeleton Based Action Recognition N-UCLA CTR-GCN Accuracy 96.5 #13 of 25 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D CTR-GCN Accuracy (CS) 92.4 #33 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D CTR-GCN Accuracy (CV) 96.8 #33 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D CTR-GCN Ensembled Modalities 4 #33 of 135 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 CTR-GCN Accuracy (Cross-Setup) 90.6 #24 of 83 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 CTR-GCN Accuracy (Cross-Subject) 88.9 #24 of 83 Archive leaderboard report
Skeleton Based Action Recognition NTU RGB+D 120 CTR-GCN Ensembled Modalities 4 #24 of 83 Archive leaderboard report

Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.

Methods

Convolution

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