Papers › On the Utility of 3D Hand Poses for Action Recognition

On the Utility of 3D Hand Poses for Action Recognition

14 Mar 2024arXiv:2403.09805archive 2025-07-28

Md Salman Shamil, Dibyadip Chatterjee, Fadime Sener, Shugao Ma, Angela Yao

3D hand pose is an underexplored modality for action recognition. Poses are compact yet informative and can greatly benefit applications with limited compute budgets. However, poses alone offer an incomplete understanding of actions, as they cannot fully capture objects and environments with which humans interact. We propose HandFormer, a novel multimodal transformer, to efficiently model hand-object interactions. HandFormer combines 3D hand poses at a high temporal resolution for fine-grained motion modeling with sparsely sampled RGB frames for encoding scene semantics. Observing the unique characteristics of hand poses, we temporally factorize hand modeling and represent each joint by its short-term trajectories. This factorized pose representation combined with sparse RGB samples is remarkably efficient and highly accurate. Unimodal HandFormer with only hand poses outperforms existing skeleton-based methods at 5x fewer FLOPs. With RGB, we achieve new state-of-the-art performance on Assembly101 and H2O with significant improvements in egocentric action recognition.

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PositionalEncoding s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · metamorphic tier: deterministic fingerprinted MIT (permissive) · ea63108588c955b8 · report
TemporalConv s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · metamorphic tier: deterministic fingerprinted MIT (permissive) · bb9b0666242adf98 · report
TransformerEncoder s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · metamorphic tier: deterministic fingerprinted MIT (permissive) · 5bbd4da441a48e72 · report
TransformerEncoderLayer s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · metamorphic tier: deterministic MIT (permissive) · f8f7be5c3f791c68 · report
Transformer_Encoder s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran MIT (permissive) · 12e7bd98c7ee2907 · report
_get_clones s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · our draft was wrong MIT (permissive) · df625bd27a59d895 · report
activation_factory s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · our draft was wrong MIT (permissive) · 5426f077b824bbb4 · report
normalize_tensor s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository ran · violated contract fingerprinted MIT (permissive) · 61e29634518807c2 · report
HF_Pose s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository unverified MIT (permissive) · 619c6b2598ece3bf · report
MicroactionEncoder s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository unverified MIT (permissive) · 0ed7906dcdd465df · report
Trajectory_SelfAttention s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository unverified MIT (permissive) · e5491621abfadb10 · report
Unimodal_TF s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository unverified MIT (permissive) · b9201db3a21104d5 · report
fc_init s-shamil/HandFormer/HandFormer/models/hf_pose.py official repository unverified MIT (permissive) · 5870cc705fd8d62e · report

Tasks

3D Action RecognitionAction Recognition

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
3D Action Recognition Assembly101 HandFormer-B/21 Actions Top-1 41.06 #1 of 7 Archive leaderboard report
3D Action Recognition Assembly101 HandFormer-B/21 Object Top-1 51.17 #1 of 7 Archive leaderboard report
3D Action Recognition Assembly101 HandFormer-B/21 Verbs Top-1 69.23 #1 of 7 Archive leaderboard report
Action Recognition H2O (2 Hands and Objects) HandFormer-B/21x8 Actions Top-1 93.39 #1 of 11 Archive leaderboard report
Action Recognition H2O (2 Hands and Objects) HandFormer-B/21x8 Hand Pose 3D #1 of 11 Archive leaderboard report
Action Recognition H2O (2 Hands and Objects) HandFormer-B/21x8 Object Label No #1 of 11 Archive leaderboard report
Action Recognition H2O (2 Hands and Objects) HandFormer-B/21x8 Object Pose No #1 of 11 Archive leaderboard report
Action Recognition H2O (2 Hands and Objects) HandFormer-B/21x8 RGB Yes #1 of 11 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.

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