Papers › Skew Orthogonal Convolutions

Skew Orthogonal Convolutions

24 May 2021arXiv:2105.11417archive 2025-07-28

Sahil Singla, Soheil Feizi

Training convolutional neural networks with a Lipschitz constraint under the l₂ norm is useful for provable adversarial robustness, interpretable gradients, stable training, etc. While 1-Lipschitz networks can be designed by imposing a 1-Lipschitz constraint on each layer, training such networks requires each layer to be gradient norm preserving (GNP) to prevent gradients from vanishing. However, existing GNP convolutions suffer from slow training, lead to significant reduction in accuracy and provide no guarantees on their approximations. In this work, we propose a GNP convolution layer called Skew Orthogonal Convolution (SOC) that uses the following mathematical property: when a matrix is {\it Skew-Symmetric}, its exponential function is an {\it orthogonal} matrix. To use this property, we first construct a convolution filter whose Jacobian is Skew-Symmetric. Then, we use the Taylor series expansion of the Jacobian exponential to construct the SOC layer that is orthogonal. To efficiently implement SOC, we keep a finite number of terms from the Taylor series and provide a provable guarantee on the approximation error. Our experiments on CIFAR-10 and CIFAR-100 show that SOC allows us to train provably Lipschitz, large convolutional neural networks significantly faster than prior works while achieving significant improvements for both standard and certified robust accuracies.

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singlasahil14/SOC officialmentioned in paperpytorch report

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fantastic_four singlasahil14/SOC/skew_ortho_conv.py official repository ran no licence file found · pointer only · 5aa5264887e73887 · report
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transpose_filter singlasahil14/soc/skew_ortho_conv.py official repository ran · our draft was wrong fingerprinted no licence file found · pointer only · 8472855416e57479 · report
SOC singlasahil14/SOC/skew_ortho_conv.py official repository unverified no licence file found · pointer only · d547d69d777b49b2 · report
transpose_filter identical code first harvested elsewhere ran · our draft was wrong fingerprinted licence of this copy not recorded · fdef065e9e837d95 · report

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Adversarial Robustness

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Convolution

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