Currently, the ART toolbox only accepts NumPy arrays as inputs to attacks, defenses and model fitting. It is understood that this is an inefficient way to utilize data since it requires a conversion from FrameworkTensor -> ndarray -> FrameworkTensor.
Framework specific attacks / defenses are on the roadmap for ART and when available we will switch to having PyTorch or TensorFlow data generators.
There are many times when creating a scenario you may want to access the underlying framework model that has been wrapped as an ART classifier. In the future we'll have a convenience method to access the models through an ART api, but in the short term they can be accessed as follows:
KerasWrapper:
underlying_model = wrapped_classifier._model
PyTorchWrapper:
underlying_model = wrapped_classifier._model._model