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Convolutional neural network: Difference between revisions

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During max pooling, remember the indices where you pulled from in "switch variables".<br>
During max pooling, remember the indices where you pulled from in "switch variables".<br>
Then when unpooling, save the max value into those indices. Other indices get values of 0.
Then when unpooling, save the max value into those indices. Other indices get values of 0.
==Spherical Images==
There are many ways to adapt convolutional layers to spherical images.
Below are just a few that I've seen.
* [http://papers.nips.cc/paper/6656-learning-spherical-convolution-for-fast-features-from-360-imagery Learning Spherical Convolution for Fast Features from 360 Imagery (NIPS 2017)] proposes using different kernels with different weights and sizes for different altitudes \(\phi\).
* [https://www.tu-chemnitz.de/etit/proaut/publications/schubert19_IV.pdf Circular Convolutional Neural Networks (IV 2019)] proposes padding the left and right sides of each input and feature map using pixels such that the input wraps around.
* [https://arxiv.org/abs/1811.08196 SpherePHD (CVPR 2019)] proposes using faces of an icosahedron as pixels. They propose a kernel which considers the neighboring 9 triangles of each triangle.