adding adversarial weight perturbation protocol

Signed-off-by: Muhammad Zaid Hameed <Zaid.Hameed@ibm.com>

art/defences/trainer/__init__.py

@@ -10,4 +10,6 @@
 from art.defences.trainer.adversarial_trainer_fbf_pytorch import AdversarialTrainerFBFPyTorch
 from art.defences.trainer.adversarial_trainer_trades import AdversarialTrainerTRADES
 from art.defences.trainer.adversarial_trainer_trades_pytorch import AdversarialTrainerTRADESPyTorch
+from art.defences.trainer.adversarial_trainer_awp import AdversarialTrainerAWP
+from art.defences.trainer.adversarial_trainer_awp_pytorch import AdversarialTrainerAWPPyTorch
 from art.defences.trainer.dp_instahide_trainer import DPInstaHideTrainer

art/defences/trainer/adversarial_trainer_awp.py

@@ -0,0 +1,131 @@
+# MIT License
+#
+# Copyright (C) The Adversarial Robustness Toolbox (ART) Authors 2023
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+# documentation files (the "Software"), to deal in the Software without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit
+# persons to whom the Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
+# Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+"""
+This module implements adversarial training with AWP protocol.
+
+| Paper link: https://proceedings.neurips.cc/paper/2020/file/1ef91c212e30e14bf125e9374262401f-Paper.pdf
+
+| It was noted that this protocol uses double perturbation mechanism i.e, perturbation on the input samples and then
+perturbation on the model parameters. Consequently, framework specific implementations are being provided in ART.
+"""
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+import abc
+from typing import Optional, Tuple, TYPE_CHECKING
+
+import numpy as np
+
+from art.defences.trainer.trainer import Trainer
+from art.attacks.attack import EvasionAttack
+from art.data_generators import DataGenerator
+
+if TYPE_CHECKING:
+    from art.utils import CLASSIFIER_LOSS_GRADIENTS_TYPE
+
+
+class AdversarialTrainerAWP(Trainer, abc.ABC):
+    """
+    This is abstract class for different backend-specific implementations of AWP protocol
+    for adversarial training.
+
+    | Paper link: https://proceedings.neurips.cc/paper/2020/file/1ef91c212e30e14bf125e9374262401f-Paper.pdf
+    """
+
+    def __init__(
+        self,
+        classifier: "CLASSIFIER_LOSS_GRADIENTS_TYPE",
+        proxy_classifier: "CLASSIFIER_LOSS_GRADIENTS_TYPE",
+        attack: EvasionAttack,
+        mode: str = "PGD",
+        gamma: float = 0.01,
+        beta: float = 6.0,
+        warmup: int = 0,
+    ):
+        """
+        Create an :class:`.AdversarialTrainerAWP` instance.
+
+        :param classifier: Model to train adversarially.
+        :param proxy_classifier: Model for adversarial weight perturbation.
+        :param attack: attack to use for data augmentation in adversarial training
+        :param mode: mode determining the optimization objective of base adversarial training and weight perturbation
+               step
+        :param gamma: The scaling factor controlling norm of weight perturbation relative to  model parameters norm
+        :param beta: The scaling factor controlling tradeoff between clean loss and adversarial loss for TRADES protocol
+        :param warmup: The number of epochs after which weight perturbation is applied
+        """
+        self._attack = attack
+        self._proxy_classifier = proxy_classifier
+        self._mode = mode
+        self._gamma = gamma
+        self._beta = beta
+        self._warmup = warmup
+        self._apply_wp = False
+        super().__init__(classifier)
+
+    @abc.abstractmethod
+    def fit(  # pylint: disable=W0221
+        self,
+        x: np.ndarray,
+        y: np.ndarray,
+        validation_data: Optional[Tuple[np.ndarray, np.ndarray]] = None,
+        batch_size: int = 128,
+        nb_epochs: int = 20,
+        **kwargs
+    ):
+        """
+        Train a model adversarially with AWP. See class documentation for more information on the exact procedure.
+
+        :param x: Training set.
+        :param y: Labels for the training set.
+        :param validation_data: Tuple consisting of validation data, (x_val, y_val)
+        :param batch_size: Size of batches.
+        :param nb_epochs: Number of epochs to use for trainings.
+        :param kwargs: Dictionary of framework-specific arguments. These will be passed as such to the `fit` function of
+               the target classifier.
+        """
+        raise NotImplementedError
+
+    @abc.abstractmethod
+    def fit_generator(  # pylint: disable=W0221
+        self,
+        generator: DataGenerator,
+        validation_data: Optional[Tuple[np.ndarray, np.ndarray]] = None,
+        nb_epochs: int = 20,
+        **kwargs
+    ):
+        """
+        Train a model adversarially with AWP using a data generator.
+        See class documentation for more information on the exact procedure.
+
+        :param generator: Data generator.
+        :param validation_data: Tuple consisting of validation data, (x_val, y_val)
+        :param nb_epochs: Number of epochs to use for trainings.
+        :param kwargs: Dictionary of framework-specific arguments. These will be passed as such to the `fit` function of
+               the target classifier.
+        """
+        raise NotImplementedError
+
+    def predict(self, x: np.ndarray, **kwargs) -> np.ndarray:
+        """
+        Perform prediction using the adversarially trained classifier.
+
+        :param x: Input samples.
+        :param kwargs: Other parameters to be passed on to the `predict` function of the classifier.
+        :return: Predictions for test set.
+        """
+        return self._classifier.predict(x, **kwargs)