PointGMM: A Neural GMM Network for Point Clouds

Point clouds are a popular representation for 3D shapes. However, they encode a particular sampling without accounting for shape priors or non-local information. We advocate for the use of a hierarchical Gaussian mixture model (hGMM), which is a compact, adaptive and lightweight representation that probabilistically defines the underlying 3D surface. We present PointGMM, a neural network that learns to generate hGMMs which are characteristic of the shape class, and also coincide with the input point cloud. PointGMM is trained over a collection of shapes to learn a class-specific prior. The hierarchical representation has two main advantages: (i) coarse-to-fine learning, which avoids converging to poor local-minima; and (ii) (an unsupervised) consistent partitioning of the input shape. We show that as a generative model, PointGMM learns a meaningful latent space which enables generating consistent interpolations between existing shapes, as well as synthesizing novel shapes. We also present a novel framework for rigid registration using PointGMM, that learns to disentangle orientation from structure of an input shape.

[1]  Baba C. Vemuri,et al.  Robust Point Set Registration Using Gaussian Mixture Models , 2011, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[2]  Yang Zhang,et al.  Point Cloud GAN , 2018, DGS@ICLR.

[3]  Leonidas J. Guibas,et al.  Learning Representations and Generative Models for 3D Point Clouds , 2017, ICML.

[4]  Gérard G. Medioni,et al.  Object modelling by registration of multiple range images , 1992, Image Vis. Comput..

[5]  Luca Antiga,et al.  Automatic differentiation in PyTorch , 2017 .

[6]  Ilya Kostrikov,et al.  Surface Networks , 2017, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[7]  Jimmy Ba,et al.  Adam: A Method for Stochastic Optimization , 2014, ICLR.

[8]  Subhransu Maji,et al.  SPLATNet: Sparse Lattice Networks for Point Cloud Processing , 2018, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[9]  Jan Kautz,et al.  HGMR: Hierarchical Gaussian Mixtures for Adaptive 3D Registration , 2018, ECCV.

[10]  Yue Wang,et al.  Dynamic Graph CNN for Learning on Point Clouds , 2018, ACM Trans. Graph..

[11]  Nico Blodow,et al.  Fast Point Feature Histograms (FPFH) for 3D registration , 2009, 2009 IEEE International Conference on Robotics and Automation.

[12]  Wei Wu,et al.  PointCNN: Convolution On X-Transformed Points , 2018, NeurIPS.

[13]  Robert C. Bolles,et al.  Random sample consensus: a paradigm for model fitting with applications to image analysis and automated cartography , 1981, CACM.

[14]  Paul J. Besl,et al.  Method for registration of 3-D shapes , 1992, Other Conferences.

[15]  Leonidas J. Guibas,et al.  Render for CNN: Viewpoint Estimation in Images Using CNNs Trained with Rendered 3D Model Views , 2015, 2015 IEEE International Conference on Computer Vision (ICCV).

[16]  Daniel Cohen-Or,et al.  MeshCNN: a network with an edge , 2019, ACM Trans. Graph..

[17]  Daniel Cohen-Or,et al.  4-points congruent sets for robust pairwise surface registration , 2008, ACM Trans. Graph..

[18]  Ming-Yu Liu,et al.  PointFlow: 3D Point Cloud Generation With Continuous Normalizing Flows , 2019, 2019 IEEE/CVF International Conference on Computer Vision (ICCV).

[19]  Leonidas J. Guibas,et al.  Learning Shape Abstractions by Assembling Volumetric Primitives , 2016, 2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[20]  Marc Levoy,et al.  Efficient variants of the ICP algorithm , 2001, Proceedings Third International Conference on 3-D Digital Imaging and Modeling.

[21]  Anath Fischer,et al.  Nesti-Net: Normal Estimation for Unstructured 3D Point Clouds Using Convolutional Neural Networks , 2018, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[22]  Yasuhiro Aoki,et al.  PointNetLK: Robust & Efficient Point Cloud Registration Using PointNet , 2019, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[23]  Leonidas J. Guibas,et al.  StructureNet , 2019, ACM Trans. Graph..

[24]  Lin Gao SDM-NET : Deep Generative Network for Structured Deformable Mesh , 2019 .

[25]  Niloy J. Mitra,et al.  Super4PCS: Fast Global Pointcloud Registration via Smart Indexing , 2019 .

[26]  Mathieu Aubry,et al.  Unsupervised cycle‐consistent deformation for shape matching , 2019, Comput. Graph. Forum.

[27]  Jiaxin Li,et al.  SO-Net: Self-Organizing Network for Point Cloud Analysis , 2018, 2018 IEEE/CVF Conference on Computer Vision and Pattern Recognition.

[28]  Leonidas J. Guibas,et al.  PointNet: Deep Learning on Point Sets for 3D Classification and Segmentation , 2016, 2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[29]  Leonidas J. Guibas,et al.  ShapeNet: An Information-Rich 3D Model Repository , 2015, ArXiv.

[30]  Lukasz Kaiser,et al.  Attention is All you Need , 2017, NIPS.

[31]  Leonidas J. Guibas,et al.  PointNet++: Deep Hierarchical Feature Learning on Point Sets in a Metric Space , 2017, NIPS.

[32]  Yi-Ping Hung,et al.  RANSAC-Based DARCES: A New Approach to Fast Automatic Registration of Partially Overlapping Range Images , 1999, IEEE Trans. Pattern Anal. Mach. Intell..

[33]  Shai Avidan,et al.  Learning to Sample , 2018, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[34]  Max Welling,et al.  Auto-Encoding Variational Bayes , 2013, ICLR.

[35]  Anath Fischer,et al.  3DmFV: Three-Dimensional Point Cloud Classification in Real-Time Using Convolutional Neural Networks , 2018, IEEE Robotics and Automation Letters.

[36]  Jonathan Masci,et al.  Geometric Deep Learning on Graphs and Manifolds Using Mixture Model CNNs , 2016, 2017 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[37]  Paul J. Besl,et al.  A Method for Registration of 3-D Shapes , 1992, IEEE Trans. Pattern Anal. Mach. Intell..

[38]  Lukasz Kaiser,et al.  Generating Wikipedia by Summarizing Long Sequences , 2018, ICLR.

[39]  Jaakko Lehtinen,et al.  Progressive Growing of GANs for Improved Quality, Stability, and Variation , 2017, ICLR.

[40]  Jan Kautz,et al.  Accelerated Generative Models for 3D Point Cloud Data , 2016, 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR).

[41]  Daniel Cohen-Or,et al.  ALIGNet: Partial-Shape Agnostic Alignment via Unsupervised Learning , 2018, ACM Trans. Graph..

[42]  Chao Chen,et al.  ClusterNet: Deep Hierarchical Cluster Network With Rigorously Rotation-Invariant Representation for Point Cloud Analysis , 2019, 2019 IEEE/CVF Conference on Computer Vision and Pattern Recognition (CVPR).

[43]  Pierre Vandergheynst,et al.  Geometric Deep Learning: Going beyond Euclidean data , 2016, IEEE Signal Process. Mag..