OAHuman: Occlusion-Aware 3D Human Reconstruction from Monocular Images
Authors: Yuanwang Yang, Hongliang Liu, Muxin Zhang, Nan Ma, Jingyu Yang, Yu-Kun Lai, Kun Li
Organizations: College of Intelligence and Computing, Tianjin University, Tianjin 300350, China · College of Artificial Intelligence, Beijing University of Technology, Beijing 100124, China · School of Electrical and Information Engineering, Tianjin University, Tianjin 300072, China · School of Computer Science and Informatics, Cardiff University, Cardiff CF24 4AG, United Kingdom
Monocular 3D human reconstruction in real-world scenarios remains highly challenging due to frequent occlusions from surrounding objects, people, or image truncation. Such occlusions lead to missing geometry and unreliable appearance cues, severely degrading the completeness and realism of reconstructed human models. Although recent neural implicit methods achieve impressive results on clean inputs, they struggle under occlusion due to entangled modeling of shape and texture. In this paper, we propose OAHuman, an occlusion-aware framework that explicitly decouples geometry reconstruction and texture synthesis for robust 3D human modeling from a single RGB image. The core innovation lies in the decoupling-perception paradigm, which addresses the fundamental issue of geometry-texture cross-contamination in occluded regions. Our framework ensures that geometry reconstruction is perceptually reinforced even in occluded areas, isolating it from texture interference. In parallel, texture synthesis is learned exclusively from visible regions, preventing texture errors from being transferred to the occluded areas. This decoupling approach enables OAHuman to achieve robust and high-fidelity reconstruction under occlusion, which has been a long-standing challenge in the field. Extensive experiments on occlusion-rich benchmarks demonstrate that OAHuman achieves superior performance in terms of structural completeness, surface detail, and texture realism, significantly improving monocular 3D human reconstruction under occlusion conditions.
Figures & tables
Fig. 1: OAHuman enables robust 3D human reconstruction under diverse occlusions. Our method successfully reconstructs complete geometry and realistic textures from monocular images across challenging occlusion types, including human-induced (left), object-induced (middle), and in-the-wild scenarios (right). Input highlights are added for visualization to indicate the target subject.
Fig. 2: Overview of OAHuman. Our method consists of a two-stage pipeline for occlusion-aware 3D human reconstruction. The first stage performs geometry restoration using a visibility-guided coarse completion (VGCC) module with feature-level supervisor regularization (FLSR) and dual-view normal refinement (DVNR). The second stage synthesizes semantically consistent textures via a geometry-faithful diffusion renderer, enabling high-fidelity reconstruction under occlusion.
Fig. 3: Feature-level supervisor regularization. We use a supervisor network trained on unoccluded data to provide hierarchical feature guidance for geometry completion. We achieve emphasis on global structure and suppression of low-level noise through depth-aware feature weighting, and enhance supervision on occluded body regions through a visibility-aware masking strategy.
Fig. 4: Qualitative comparison of geometry reconstruction results.
Fig. 5: Qualitative comparison of novel view synthesis results.
Method
CustomHumans [ 33 ]
2k2k [ 34 ]
Geometry
Novel View Synthesis
Geometry
Novel View Synthesis
CD ↓
P2S ↓
Normal ↓
SSIM ↑
PSNR ↑
LPIPS ↓
CD ↓
P2S ↓
Normal ↓
SSIM ↑
PSNR ↑
LPIPS ↓
ECON
1.9223
1.2334
1.5150
-
-
-
2.8937
2.6024
3.1966
-
-
-
SiTH
4.2868
1.8328
2.0597
0.8698
23.08
0.1261
4.1096
3.2313
3.0603
0.8706
15.07
0.1448
R 2 Human
1.6711
1.5694
1.6085
0.8331
21.84
0.1981
2.9063
2.5428
2.4865
0.8325
15.53
0.1168
PSHuman
3.0263
2.5027
2.7213
0.8257
18.85
0.4894
3.2485
2.6949
2.7534
0.8838
15.99
0.1142
TABLE I: Quantitative comparison of geometry reconstruction and novel view synthesis.
Method
CD ↓
P2S ↓
Normal ↓
VGCC w/o FLSR
1.4283
1.4281
1.4551
VGCC
1.2547
1.2275
1.3717
2D Normal Completion
0.9835
0.9408
1.2124
Ours(full)
0.9440
0.8831
1.1082
TABLE II: Quantitative results of ablation study.
Fig. 6: Qualitative results of ablation study.
Method
SSIM ↑
PSNR ↑
LPIPS ↓
w/o Mesh normal
0.8672
22.45
0.0891
w/ Mesh normal
0.8759
23.51
0.0833
TABLE III: Ablation on the renderer with different normal sources.
Fig. 7: Qualitative comparison of renderer ablations. Using refined mesh normals leads to more faithful texture generation.
Fig. 8: Qualitative reconstruction results under accumulative occlusion.
3D human mesh recovery from monocular RGB images aims to estimate anatomically plausible 3D human models for downstream applications, but remains challenging under partial or severe occlusions. Regression-based methods are efficient yet often produce implausible or inaccurate results in unconstrained scenarios, while diffusion-based methods provide strong generative priors for occluded regions but may weaken fidelity to rare poses due to over-reliance on generation. To address these limitations, we propose a brain-inspired synergistic framework that integrates the discriminative power of vision transformers with the generative capability of conditional diffusion models. Specifically, the ViT-based pathway extracts deterministic visual cues from visible regions, while the diffusion-based pathway synthesizes structurally coherent human body representations. To effectively bridge the two pathways, we design a diverse-consistent feature learning module to align discriminative features with generative priors, and a cross-attention multi-level fusion mechanism to enable bidirectional interaction across semantic levels. Experiments on standard benchmarks demonstrate that our method achieves superior performance on key metrics and shows strong robustness in complex real-world scenarios.
Yang Liu, Zhiyong Zhang
School of Electronics and Communication Engineering, Sun Yat-sen University, Shenzhen, Guangdong, China
Monocular 3D clothed human reconstruction aims to generate a complete and realistic textured 3D avatar from a single image. Existing methods are commonly trained under multi-view supervision with annotated geometric priors, and during inference, these priors are estimated by the pre-trained network from the monocular input. These methods are constrained by three key limitations: texturally by unavailability of training data, geometrically by inaccurate external priors, and systematically by biased single-modality supervision, all leading to suboptimal reconstruction. To address these issues, we propose a novel reconstruction framework, named MultiGO++, which achieves effective systematic geometry-texture collaboration. It consists of three core parts: (1) A multi-source texture synthesis strategy that constructs 15,000+ 3D textured human scans to improve the performance on texture quality estimation in challenge scenarios; (2) A region-aware shape extraction module that extracts and interacts features of each body region to obtain geometry information and a Fourier geometry encoder that mitigates the modality gap to achieve effective geometry learning; (3) A dual reconstruction U-Net that leverages geometry-texture collaborative features to refine and generate high-fidelity textured 3D human meshes. Extensive experiments on two benchmarks and many in-the-wild cases show the superiority of our method over state-of-the-art approaches.
Nanjie Yao, Gangjian Zhang, Wenhao Shen +3
The Hong Kong University of Science and Technology (Guangzhou), Guangzhou 511442, China · Nanyang Technological University, Singapore 639798
Reconstructing textured 3D human models from a single image is fundamental for AR/VR and digital human applications. However, existing methods mostly focus on single individuals and thus fail in multi-human scenes, where naive composition of individual reconstructions often leads to artifacts such as unrealistic overlaps, missing geometry in occluded regions, and distorted interactions. These limitations highlight the need for approaches that incorporate group-level context and interaction priors. We introduce a holistic method that explicitly models both group- and instance-level information. To mitigate perspective-induced geometric distortions, we first transform the input into a canonical orthographic space. Our primary component, Human Group-Instance Multi-View Diffusion (HUG-MVD), then generates complete multi-view normals and images by jointly modeling individuals and group context to resolve occlusions and proximity. Subsequently, the Human Group-Instance Geometric Reconstruction (HUG-GR) module optimizes the geometry by leveraging explicit, physics-based interaction priors to enforce physical plausibility and accurately model inter-human contact. Finally, the multi-view images are fused into a high-fidelity texture. Together, these components form our complete framework, HUG3D. Extensive experiments show that HUG3D significantly outperforms both single-human and existing multi-human methods, producing physically plausible, high-fidelity 3D reconstructions of interacting people from a single image. Project page: https://jongheean11.github.io/HUG3D_project
Gwanghyun Kim, Junghun James Kim, Suh Yoon Jeon +2
Dept. of Electrical and Computer Engineering, Seoul National University, Republic of Korea · IPAI, Seoul National University, Republic of Korea · INMC, Seoul National University, Republic of Korea