Semantic segmentation of 3D point cloud data is essential for enhanced high-level perception in autonomous platforms. Furthermore, given the increasing deployment of LiDAR sensors onboard of cars and drones, a special emphasis is also placed on non-computationally intensive algorithms that operate on mobile GPUs. Previous efficient state-of-the-art methods relied on 2D spherical projection of point clouds as input for 2D fully convolutional neural networks to balance the accuracy-speed trade-off. This paper introduces a novel approach for 3D point cloud semantic segmentation that exploits multiple projections of the point cloud to mitigate the loss of information inherent in single projection methods. Our Multi-Projection Fusion (MPF) framework analyzes spherical and bird's-eye view projections using two separate highly-efficient 2D fully convolutional models then combines the segmentation results of both views. The proposed framework is validated on the SemanticKITTI dataset where it achieved a mIoU of 55.5 which is higher than state-of-the-art projection-based methods RangeNet++ and PolarNet while being 1.6x faster than the former and 3.1x faster than the latter.

这篇论文提出了一种基于多视角融合的 3D 点云语义分割方法，通过对球面和鸟瞰图进行高效的二维卷积神经网络分割，结合两个视角的分割结果，有效缓解了单个视角方法中存在的信息损失问题，既能提高准确率又能保证速度，在 SemanticKITTI 数据集上实现了高准确率（mIoU为 55.5），同时比目前最先进的基于投影的方法 RangeNet++ 和 PolarNet 分别快1.6倍和3.1倍。

多投影融合用于3D LiDAR点云的实时语义分割