Title
L2G Auto-encoder: Understanding Point Clouds by Local-to-Global Reconstruction with Hierarchical Self-Attention
Abstract
Auto-encoder is an important architecture to understand point clouds in an encoding and decoding procedure of self reconstruction. Current auto-encoder mainly focuses on the learning of global structure by global shape reconstruction, while ignoring the learning of local structures. To resolve this issue, we propose Local-to-Global auto-encoder (L2G-AE) to simultaneously learn the local and global structure of point clouds by local to global reconstruction. Specifically, L2G-AE employs an encoder to encode the geometry information of multiple scales in a local region at the same time. In addition, we introduce a novel hierarchical self-attention mechanism to highlight the important points, scales and regions at different levels in the information aggregation of the encoder. Simultaneously, L2G-AE employs a recurrent neural network (RNN) as decoder to reconstruct a sequence of scales in a local region, based on which the global point cloud is incrementally reconstructed. Our outperforming results in shape classification, retrieval and upsampling show that L2G-AE can understand point clouds better than state-of-the-art methods.
Year
DOI
Venue
2019
10.1145/3343031.3350960
Proceedings of the 27th ACM International Conference on Multimedia
Keywords
DocType
ISBN
auto-encoder, hierarchical attention, interpolation layer, point cloud, recurrent neural network, unsupervised learning
Conference
978-1-4503-6889-6
Citations 
PageRank 
References 
8
0.47
26
Authors
5
Name
Order
Citations
PageRank
Xinhai Liu1322.17
Han Zhizhong219818.28
Xin Wen3242.71
Yu-shen Liu431923.20
Zwicker Matthias52513129.25