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arXiv · 1904.05146

DeepSphere: towards an equivariant graph-based spherical CNN

Michaël Defferrard·Nathanaël Perraudin·Tomasz Kacprzak·Raphael Sgier
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Abstract

Spherical data is found in many applications. By modeling the discretized sphere as a graph, we can accommodate non-uniformly distributed, partial, and changing samplings. Moreover, graph convolutions are computationally more efficient than spherical convolutions. As equivariance is desired to exploit rotational symmetries, we discuss how to approach rotation equivariance using the graph neural network introduced in Defferrard et al. (2016). Experiments show good performance on rotation-invariant learning problems. Code and examples are available at https://github.com/SwissDataScienceCenter/DeepSphere

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Michaël Defferrard, Nathanaël Perraudin, Tomasz Kacprzak, Raphael Sgier. 2019-04-08. DeepSphere: towards an equivariant graph-based spherical CNN. https://arxiv.org/abs/1904.05146

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