SmoothMix PyTorch Implementation

[f4str]

Description

Implementation of the SmoothMix training method for PyTorch models through the art.estimators.certification.PyTorchSmoothMix class. Includes the art.estimators.certification.SmoothMixMixin abstract class for future TensorFlow and Numpy implementations.

Additionally includes a notebook that demonstrates the usage. The notebooks/README.md is updated accordingly to include this new notebook.

This PR is continued and consolidated from

• PR Addition of SmoothMix Training in the Randomized Smoothing Module #1668
• PR SmoothMix Addition #1705

Paper Link: https://arxiv.org/abs/2111.09277
Code Repository based on paper: https://github.com/jh-jeong/smoothmix

Fixes # (issue)

Type of change

Please check all relevant options.

• Improvement (non-breaking)
• Bug fix (non-breaking)
• New feature (non-breaking)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Testing

Please describe the tests that you ran to verify your changes. Consider listing any relevant details of your test configuration.

• Unit tests for the PyTorchSmoothMix class

Test Configuration:

• OS
• Python version
• ART version or commit number
• TensorFlow / Keras / PyTorch / MXNet version

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[f4str]

Tagging @keykholt and @rahmati for updates. PR #1705 should be closed in favor of this one.

[codecov-commenter]

Codecov Report

Merging #1988 (6f9abfb) into dev_1.14.0 (5ddd8ef) will decrease coverage by 0.06%.
The diff coverage is 81.03%.

@@              Coverage Diff               @@
##           dev_1.14.0    #1988      +/-   ##
==============================================
- Coverage       85.41%   85.36%   -0.06%     
==============================================
  Files             290      293       +3     
  Lines           25437    25669     +232     
  Branches         4573     4599      +26     
==============================================
+ Hits            21728    21913     +185     
- Misses           2541     2580      +39     
- Partials         1168     1176       +8     

Impacted Files	Coverage Δ
art/estimators/certification/smoothmix/pytorch.py	76.38% <76.38%> (ø)
...rt/estimators/certification/smoothmix/smoothmix.py	88.37% <88.37%> (ø)
art/estimators/certification/smoothmix/__init__.py	100.00% <100.00%> (ø)
art/estimators/certification/abstain.py	90.90% <0.00%> (-9.10%)	⬇️
art/estimators/poison_mitigation/strip/strip.py	94.44% <0.00%> (-5.56%)	⬇️

[f4str]

Closed in favor of #2218