Neural Descriptors: Self-Supervised Learning of Robust Local Surface Descriptors Using Polynomial Patches
Gal Yona, Roy Velich, Ron Kimmel, Ehud Rivlin
TL;DR
This work tackles robust, dense shape correspondence under non-rigid deformations, partial observations, and topological noise by learning sampling-invariant local descriptors through self-supervision. It introduces a synthetic data pipeline of local patches defined by random polynomials and a DeltaConv-based feature extractor trained with SimSiam to produce $2048$-dimensional patch descriptors, with per-point features of $512$ dimensions. The approach achieves state-of-the-art results on FAUST, SCAPE, TOPKIDS, and SHREC'16, demonstrating superior robustness to holes and topological perturbations and strong integration with existing shape-matching pipelines such as RobustFMNet. This yields practical impact by enabling more reliable 3D shape analysis in scenes with incomplete or noisy data, while highlighting areas for future improvement in anisotropic meshes.
Abstract
Classical shape descriptors such as Heat Kernel Signature (HKS), Wave Kernel Signature (WKS), and Signature of Histograms of OrienTations (SHOT), while widely used in shape analysis, exhibit sensitivity to mesh connectivity, sampling patterns, and topological noise. While differential geometry offers a promising alternative through its theory of differential invariants, which are theoretically guaranteed to be robust shape descriptors, the computation of these invariants on discrete meshes often leads to unstable numerical approximations, limiting their practical utility. We present a self-supervised learning approach for extracting geometric features from 3D surfaces. Our method combines synthetic data generation with a neural architecture designed to learn sampling-invariant features. By integrating our features into existing shape correspondence frameworks, we demonstrate improved performance on standard benchmarks including FAUST, SCAPE, TOPKIDS, and SHREC'16, showing particular robustness to topological noise and partial shapes.
