Wang, J., Cheng, Z., Zhao, N., Cheng, J., & Yang, X. (2024). On-the-fly Point Feature Representation for Point Clouds Analysis. Proceedings of the 32nd ACM International Conference on Multimedia, 9204–9213. https://doi.org/10.1145/3664647.3680700
Abstract:
Point cloud analysis is challenging due to its unique characteristics
of unorderness, sparsity and irregularity. Prior works attempt to
capture local relationships by convolution operations or attention
mechanisms, exploiting geometric information from coordinates
implicitly. These methods, however, are insufficient to describe the
explicit local geometry, e.g., curvature and orientation. In this paper,
we propose On-the-fly Point Feature Representation (OPFR),
which captures abundant geometric information explicitly through
Curve Feature Generator module. This is inspired by Point Feature
Histogram (PFH) from computer vision community. However, the
utilization of vanilla PFH encounters great difficulties when applied
to large datasets and dense point clouds, as it demands considerable
time for feature generation. In contrast, we introduce the
Local Reference Constructor module, which approximates the local
coordinate systems based on triangle sets. Owing to this, our
OPFR only requires extra 1.56ms for inference (65× faster than
vanilla PFH) and 0.012M more parameters, and it can serve as a
versatile plug-and-play module for various backbones, particularly
MLP-based and Transformer-based backbones examined in this
study. Additionally, we introduce the novel Hierarchical Sampling
module aimed at enhancing the quality of triangle sets, thereby ensuring
robustness of the obtained geometric features. Our proposed
method improves overall accuracy (OA) on ModelNet40 from 90.7%
to 94.5% (+3.8%) for classification, and OA on S3DIS Area-5 from
86.4% to 90.0% (+3.6%) for semantic segmentation, respectively,
building upon PointNet++ backbone. When integrated with Point
Transformer backbone, we achieve state-of-the-art results on both
tasks: 94.8% OA on ModelNet40 and 91.7% OA on S3DIS Area-5.
License type:
Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
Funding Info:
This research / project is supported by the Agency for Science, Technology and Research (A*STAR) - Manufacturing, Trade, and Connectivity Programmatic Funds
Grant Reference no. : M23L7b0021