1.5.0

New features and improvements

• Two new losses based on standard Keras cross-entropy losses with a settable temperature for softmax:
  • TauSparseCategoricalCrossentropy equivalent to Keras SparseCategoricalCrossentropy
  • TauBinaryCrossentropy equivalent to Keras BinaryCrossentropy
• New module deel.lip.compute_layer_sv to compute the largest and lowest singular values of layers compute_layer_sv() or of a whole model compute_model_sv().
• Power iteration algorithm for convolution.
• New "Getting Started" tutorial to introduce 1-Lipschitz neural networks.
• Documentation migration from Sphinx to MkDocs.

API changes

• Activations are now imported via deel.lip.layers submodule, e.g. deel.lip.layers.GroupSort instead of deel.lip.activations.GroupSort. We adopted the same convention as Keras. The legacy submodule is still available for retro-compatibility but will be removed in a future release.
• Unconstrained layers must now be imported using deel.lip.layers.unconstrained submodule, e.g. deel.lip.layers.unconstrained.PadConv2D.

Fixes

• Fix InvertibleUpSampling __call__() returning None.

Full changelog: v1.4.0...v1.5.0

1.4.0

New features and improvements

• Two new layers:
  • SpectralConv2DTranspose, a Lipschitz version of the Keras Conv2DTranspose layer
  • activation layer Householder which is a parametrized generalization of the GroupSort2
• Two new regularizers to foster orthogonality:
  • LorthRegularizer for an orthogonal convolution
  • OrthDenseRegularizer for an orthogonal Dense matrix kernel
• Two new losses for Lipschitz networks:
  • TauCategoricalCrossentropy, a categorical cross-entropy loss with temperature scaling tau
  • CategoricalHinge, a hinge loss for multi-class problems based on the implementation of the Keras CategoricalHinge
• Two new custom callbacks:
  • LossParamScheduler to change loss hyper-parameters during training, e.g. min_margin, alpha and tau
  • LossParamLog to log the value of loss parameters
• The Björck orthogonalization algorithm was accelerated.
• Normalizers (power iteration and Björck) use tf.while_loop and the swap_memory argument can be globally set using set_swap_memory(bool). Default value is True to save memory usage in GPU.
• The new function set_stop_grad_spectral(bool) allows to bypass the back-propagation in the power iteration algorithm that computes the spectral norm. Default value is True. Stopping gradient propagation reduces runtime.
• Due to bugs in TensorFlow serialization of custom losses and metrics (version 2.0 and 2.1), deel-lip now only supports TensorFlow >= 2.2.

Fixes

• SpectralInitializer does not reuse anymore the same base initializer in multiple instances.

Full Changelog: v1.3.0...v1.4.0

1.3.0

New features and improvements

• New layer PadConv2D to handle in particular circular padding in convolutional layer
• Losses handle multi-label classification
• Losses are now element-wise. reduction parameter in custom losses can be set to None.
• New metrics are introduced: ProvableAvgRobustness and ProvableRobustAccuracy

API changes

• KR is not a function anymore but a class derived from tf.keras.losses.Loss.
• negative_KR function was removed. Use the loss HKR(alpha=0) instead.
• The stopping criterion for Spectral normalization and Björck orthogonalization (iterative methods) is no more the number of iterations niter_spectral and niter_bjorck. The methods are now stopped based on the difference between two iterations: eps_spectral and eps_bjorck. This API change occurs in:
  • Lipschitz layers, such as SpectralDense and SpectralConv2D
  • normalizer reshaped_kernel_orthogonalization
  • constraint SpectralConstraint
  • initializer SpectralInitializer

Full Changelog: v1.2.0...v1.3.0

1.2.0

this revision contains:

• code refactoring: storing wbar in a tf.variable
• update of the documentation's notebooks
• update of the Callbacks, Initializers, Constraints...
• update of the losses and tests for losses
• improved loss stability for small batches
• added ScaledGlobalL2NormPooling2D
• new way to export keras serializable objects

This ends the support of tf2.0. Only versions >= tf2.1 are supported.

1.1.1

This revision contains:

• bugfixes in losses.py: fixed a problem with data types in HKR_loss and fixed a weighting problem in KR_multiclass_loss.
• changed behavior of FrobeniusDense in the multi class setup : now using FrobeniusDense with 10 output neurons is now equivalent to stack 10 FrobeniuDense layers with 1 output neuron. The L2normalization is performed on each neuron instead of the full weight matrix

1.1.0

This version add new features:

• InvertibleDownSampling and InvertibleUpSampling
• multiclass extension of the HKR loss

It also contains the multiple fixes for:

• bug with L2NormPooling
• bug with vanilla_export
• bug with tf.function annotation causing incorrect Lipschitz constant in Sequential (for constant others than 1).

Breaking changes:

• the true_values parameter has been removed in binary HKR as both (1, -1) and (1,0) are handled automatically.

1.0.2

Features

• Tensorflow 2.3 support.

1.0.1

Features

• Improvements for Björck initializers.
• Stride handling in convolutionnal layers.

Bug fixes

• Fixed bug with ScaledL2NormPooling which was causing nan values to appear after the first training step.

Initial release - v1.0.0

Controlling the Lipschitz constant of a layer or a whole neural network has many applications ranging from adversarial robustness to Wasserstein distance estimation.

This library provides implementation of k-Lispchitz layers for keras.