HMC: Hierarchical Mesh Coarsening for Skeleton-free Motion Retargeting

TL;DR

This paper introduces a hierarchical mesh coarsening approach for skeleton-free motion retargeting that better preserves local-part motions and details, outperforming previous methods on standard datasets.

Contribution

It proposes a novel coarse-to-fine mesh coarsening and refinement pipeline that enhances motion transfer accuracy and detail preservation in skeleton-free retargeting.

Findings

Achieves 25% improvement in mesh Euclidean distance over state-of-the-art methods.

Effectively preserves local-part motions and mesh details.

Enhances moving consistency of different body parts.

Abstract

We present a simple yet effective method for skeleton-free motion retargeting. Previous methods transfer motion between high-resolution meshes, failing to preserve the inherent local-part motions in the mesh. Addressing this issue, our proposed method learns the correspondence in a coarse-to-fine fashion by integrating the retargeting process with a mesh-coarsening pipeline. First, we propose a mesh-coarsening module that coarsens the mesh representations for better motion transfer. This module improves the ability to handle small-part motion and preserves the local motion interdependence between neighboring mesh vertices. Furthermore, we leverage a hierarchical refinement procedure to complement missing mesh details by gradually improving the low-resolution mesh output with a higher-resolution one. We evaluate our method on several well-known 3D character datasets, and it yields an average improvement of 25% on point-wise mesh euclidean distance (PMD) against the start-of-art method. Moreover, our qualitative results show that our method is significantly helpful in preserving the moving consistency of different body parts on the target character due to disentangling body-part structures and mesh details in a hierarchical way.