Organizations: School of Computer Science, Northwestern Polytechnical University · Xidian University · School of Cybersecurity, Northwestern Polytechnical University
State-of-the-art whole-body pose estimators often lack robustness, producing anatomically implausible predictions in challenging scenes. We posit this failure stems from spurious correlations learned from visual context, a problem we formalize using a Structural Causal Model (SCM). The SCM identifies visual context as a confounder that creates a non-causal backdoor path, corrupting the model's reasoning. We introduce the Causal Intervention Graph Pose (CIGPose) framework to address this by approximating the true causal effect between visual evidence and pose. The core of CIGPose is a novel Causal Intervention Module: it first identifies confounded keypoint representations via predictive uncertainty and then replaces them with learned, context-invariant canonical embeddings. These deconfounded embeddings are processed by a hierarchical graph neural network that reasons over the human skeleton at both local and global semantic levels to enforce anatomical plausibility. Extensive experiments show CIGPose achieves a new state-of-the-art on COCO-WholeBody. Notably, our CIGPose-x model achieves 67.0% AP, surpassing prior methods that rely on extra training data. With the additional UBody dataset, CIGPose-x is further boosted to 67.5% AP, demonstrating superior robustness and data efficiency. The codes and models are publicly available at https://github.com/53mins/CIGPose.
Figures & tables
Figure 1: (a) Comparison of CIGPose with related models for whole-body pose estimation on COCO-WholeBody. (b) Qualitative comparison between CIGPose-x and RTMPose-x [ 16 ] .
Figure 2: (a) The proposed Structural Causal Model (SCM) for keypoint estimation, (b) The intervened SCM after applying the do -operator to the keypoint embeddings, (c) The realization of each component within our Causal Intervention Module (CIM).
Figure 3: Validation of confounder score sc(k) on COCO-WholeBody [ 19 ] . The confounder score is significantly higher for occluded keypoints than for visible ones, for both (a) easily occluded limb keypoints and (b) all keypoints combined.
Figure 4: UMAP visualization of initial contextual embeddings vs. their corresponding learned canonical embeddings.
Figure 5: Overview of our CIGPose architecture. During training, embeddings are processed in two paths: (1) a counterfactual path where our CIM module deconfounds them before the Hierarchical GNN, and (2) an observational path using original embeddings for consistency. Inference relies solely on the counterfactual path.
Method
Input Size
GFLOPs
whole-body
body
foot
face
hand
AP
AR
AP
AR
AP
AR
AP
AR
AP
AR
Whole-
SN† [ 12 ]
N/A
272.3
32.7
45.6
42.7
58.3
9.9
36.9
64.9
69.7
40.8
58.0
body
OpenPose [ 3 ]
N/A
451.1
44.2
52.3
56.3
61.2
53.2
64.5
76.5
84.0
38.6
43.3
Bottom-
PAF† [ 2 ]
512 × 512
329.1
29.5
40.5
38.1
52.6
5.3
27.8
65.6
70.1
35.9
52.8
up
AE [ 32 ]
512 × 512
212.4
44.0
54.5
58.0
66.1
57.7
72.5
58.8
65.4
48.1
57.4
SimpleBaseline [ 50 ]
384 × 288
20.4
57.3
67.1
66.6
74.7
63.5
76.3
73.2
81.2
53.7
64.7
Table 1: Whole-body pose estimation results on COCO-WholeBody [ 19 , 51 ] V1.0 dataset. “*” denotes the model that relies on two-stage distillation and additional training data from the UBody dataset [ 27 ] . “†” indicates multi-scale testing. Flip test is used.
Method
#Params
GFLOPs
COCO Val
AP
AR
SimpleBaseline [ 50 ]
60M
15.7
73.5
79.0
HRNet† [ 43 ]
64M
32.9
76.3
81.2
HRFormer-B† [ 59 ]
43M
26.8
77.2
82.0
ViTPose++-B [ 53 ]
86M
17.1
77.0
82.6
RTMPose-m [ 16 ]
14M
1.9
75.8
80.6
Table 2: Comparisons of CIGPose and SOTA methods on COCO val set [ 28 ] . The default input resolution is 256 × 192, “†” denotes the input resolution is 384 × 288.
Method
#Params
AP
AP E
AP M
AP H
Bottom-up methods
OpenPose [ 3 ]
-
-
62.7
48.7
32.3
HrHRNet [ 4 ]
63.8M
65.9
73.3
66.5
57.9
DEKR [ 10 ]
65.7M
67.3
74.6
68.1
58.7
SWAHR [ 31 ]
63.8M
71.6
78.9
72.4
63.0
Top-down methods
Table 3: Comparisons with SOTA methods on the CrowdPose [ 24 ] dataset. The default input resolution is 256 × 192, “†” denotes the input resolution is 384 × 288.
Figure 6: Qualitative comparison of CIGPose-x against the baseline RTMPose-x [ 16 ] on challenging images. From left to right: input image, RTMPose-x, and CIGPose-x.
CIM
Gh
Gp
Model
AP
AR
✓
✓
✓
CIGPose-l
66.3 (+1.5)
74.9 (+1.9)
CIGPose-x
67.0 (+1.7)
75.4 (+2.1)
✗
✓
✓
CIGPose-l
66.0 (+1.2)
74.8 (+1.8)
CIGPose-x
66.8 (+1.5)
75.5 (+2.2)
✗
✗
✓
CIGPose-l
65.6 (+0.8)
74.6 (+1.6)
CIGPose-x
66.3 (+1.0)
75.0 (+1.7)
Table 4: Ablation study of CIGPose on COCO-WholeBody. Values in parentheses are AP/AR gains.
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
Easy-drop p
Kept inst.
Mean Δˉ (px)
95% CI
0.00
104,125
8.47
[8.20, 8.72]
0.30
72,888
10.14
[9.78, 10.48]
0.50
52,063
10.45
[10.02, 10.87]
Appendix
Table 5: Within instance top- n enrichment on COCO-WholeBody. Keypoints selected by sc exhibit larger localization error than the remaining keypoints in the same instance. Easy-drop p denotes the fraction of easiest instances removed when forming harder subsets, and 95% CIs are percentile bootstrap intervals over instances.
Figure 7: Visualization of posterior probability distributions. (A) For an unconfounded keypoint (green circle, nose), the distributions exhibit sharp, high peaks, indicating low uncertainty. (B) For a confounded keypoint (red circle, left ankle), which is occluded and in shadow, the distributions are diffuse with low peaks, signaling high predictive ambiguity.
Hyperparameter
Value
Optimizer
AdamW
Base Learning Rate
2×10−3
Weight Decay
0.05
LR Schedule
Cosine Annealing
Warm-up Iterations
1000
Max Gradient Norm
35
Appendix
Table 6: Key training hyperparameters for the CIGPose-x model.
Body Part
Intervention Freq. (%)
Face
0.67
Torso
0.16
Arms
0.24
Hands
0.90
Legs
0.89
Feet
1.36
Appendix
Table 7: Intervention frequency per body part on COCO-WholeBody. The module intervenes most often on extremities, which are most prone to confounding.
λ
Whole-Body AP (%)
0
65.8
0.01
66.1
0.1
66.3
0.5
65.9
Appendix
Table 8: Effect of the counterfactual consistency loss weight λ .
Intervention Strategy (Training)
Whole-Body AP (%)
Threshold τ=0.7
65.9
Threshold τ=0.8
65.8
Top- n ( n=11 )
66.1
Top- n ( n=13 )
66.3
Top- n ( n=15 )
66.0
Appendix
Table 9: Comparison of intervention strategies during training. The fixed-budget ‘top- n ‘ strategy provides a more stable and effective training signal, with n=13 yielding the best result on COCO-WholeBody.
Accurately recovering hand poses within the body context remains a major challenge in 3D whole-body pose estimation. This difficulty arises from a fundamental supervision gap: whole-body pose estimators are trained on full-body datasets with limited hand diversity, while hand-only estimators, trained on hand-centric datasets, excel at detailed finger articulation but lack global body awareness. To address this, we propose Hand4Whole++, a modular framework that leverages the strengths of both pre-trained whole-body and hand pose estimators. We introduce CHAM (Conditional Hands Modulator), a lightweight module that modulates the whole-body feature stream using hand-specific features extracted from a pre-trained hand pose estimator. This modulation enables the whole-body model to predict wrist orientations that are both accurate and coherent with the upper-body kinematic structure, without retraining the full-body model. In parallel, we directly incorporate finger articulations and hand shapes predicted by the hand pose estimator, aligning them to the full-body mesh via differentiable rigid alignment. This design allows Hand4Whole++ to combine globally consistent body reasoning with fine-grained hand detail. Extensive experiments demonstrate that Hand4Whole++ substantially improves hand accuracy and enhances overall full-body pose quality.
Estimating the 6DoF pose of a novel object with a single reference view is challenging due to occlusions, view-point changes, and outliers. A core difficulty lies in finding robust cross-view correspondences, as existing methods often rely on discrete one-to-one matching that is non-differentiable and tends to collapse onto sparse key-points. We propose Confidence-aware Optimal Geometric Correspondence (COG), an unsupervised framework that formulates correspondence estimation as a confidence-aware optimal transport problem. COG produces balanced soft correspondences by predicting point-wise confidences and injecting them as optimal transport marginals, suppressing non-overlapping regions. Semantic priors from vision foundation models further regularize the correspondences, leading to stable pose estimation. This design integrates confidence into the correspondence finding and pose estimation pipeline, enabling unsupervised learning. Experiments show unsupervised COG achieves comparable performance to supervised methods, and supervised COG outperforms them.
Yuchen Che, Jingtu Wu, Hao Zheng +1
Institute of Science Tokyo · RIKEN · Tohoku University
Transformer-based methods have achieved strong performance in monocular 3D human pose estimation, but most existing approaches organise spatial and temporal reasoning as separate stages, which may weaken unified spatial-temporal interdependencies inherent in human motion and compress frame-level structural information before temporal modelling. In this paper, we propose HSTGFormer, a graph-enhanced Transformer framework that reformulates spatial-temporal reasoning as localised coupled graph aggregation over joint-time nodes. Specifically, HSTGFormer introduces a Hyper Spatial-Temporal Graph (HSTG), which decomposes global spatial-temporal reasoning into local spatial-temporal receptive fields around individual joint-time nodes by extending per-frame skeleton graphs into temporal neighbourhoods, thereby enabling structure-aware coupled reasoning while preserving local structural motion information. It further incorporates an Adaptive Dual-Scale Temporal Graph (ADSTG) to capture joint-specific temporal dependencies over complementary short- and long-range windows. A lightweight node-wise fusion module further adaptively integrates the two graph representations for each joint-time node. Experiments on Human3.6M and MPI-INF-3DHP show that HSTGFormer achieves strong accuracy with high computational efficiency.
Ruochen Li, Shuang Chen, Wenke E +2
Department of Computer Science Durham University Durham, UK