Generative models have proven effective at modeling 3D shapes and their statistical variations. In this paper we investigate their application to point clouds, a 3D shape representation widely used in computer vision for which, however, only few generative models have yet been proposed. We introduce a latent variable model that builds on normalizing flows with affine coupling layers to generate 3D point clouds of an arbitrary size given a latent shape representation. To evaluate its benefits for shape modeling we apply this model for generation, autoencoding, and single-view shape reconstruction tasks. We improve over recent GAN-based models in terms of most metrics that assess generation and autoencoding. Compared to recent work based on continuous flows, our model offers a significant speedup in both training and inference times for similar or better performance. For single-view shape reconstruction we also obtain results on par with state-of-the-art voxel, point cloud, and mesh-based methods.

该研究论文探讨生成模型在三维点云形状建模方面的应用，提出一种基于归一化流和仿射耦合层的潜在变量模型，用于生成、自编码和单视角形状重构任务，相较最近的基于 GAN 和基于连续流的模型，该模型在训练和推理速度上有明显提升，并在特定指标上实现了优于其他模型的表现，包括单视角形状重构等。

离散点流网络用于高效点云生成