Animatable Implicit Neural Representations for Creating Realistic Avatars from Videos

TPAMI 2024, ICCV 2021


Sida Peng1, Zhen Xu1, Junting Dong1, Qianqian Wang2, Shangzhan Zhang1, Qing Shuai1, Hujun Bao1, Xiaowei Zhou1

1State Key Lab of CAD & CG, Zhejiang University    2Cornell University

Abstract


This paper is an extension of Animatable NeRF, which has better reconstruction and rendering results.

This paper addresses the challenge of reconstructing an animatable human model from a multi-view video. Some recent works have proposed to decompose a non-rigidly deforming scene into a canonical neural radiance field and a set of deformation fields that map observation-space points to the canonical space, thereby enabling them to learn the dynamic scene from images. However, they represent the deformation field as translational vector field or SE(3) field, which makes the optimization highly under-constrained. Moreover, these representations cannot be explicitly controlled by input motions. Instead, we introduce a pose-driven deformation field based on the linear blend skinning algorithm, which combines the blend weight field and the 3D human skeleton to produce observation-to-canonical correspondences. Since 3D human skeletons are more observable, they can regularize the learning of the deformation field. Moreover, the pose-driven deformation field can be controlled by input skeletal motions to generate new deformation fields to animate the canonical human model. Experiments show that our approach significantly outperforms recent human modeling methods.


Reconstruction results


Comparison on 3D reconstruction from monocular videos
More reconstruction results

Rendering results


Comparison on novel view synthesis
Comparison on novel pose synthesis
Novel pose synthesis under complex human poses

Ablation studies


Non-rigid deformations captured by the displacement fields
Ablation study on canonical-space viewing direction
Ablation study on neural feature fields

Citation



@article{peng2024animatable,
    title={Animatable Implicit Neural Representations for Creating Realistic Avatars from Videos},
    author={Peng, Sida and Xu, Zhen and Dong, Junting and Wang, Qianqian and Zhang, Shangzhan and Shuai, Qing and Bao, Hujun and Zhou, Xiaowei},
    journal={TPAMI},
    year={2024},
    publisher={IEEE}
}
@inproceedings{peng2021animatable,
  title={Animatable Neural Radiance Fields for Modeling Dynamic Human Bodies},
  author={Peng, Sida and Dong, Junting and Wang, Qianqian and Zhang, Shangzhan and Shuai, Qing and Zhou, Xiaowei and Bao, Hujun},
  booktitle={ICCV},
  year={2021}
}