Adversarial purification using generative models demonstrates strong
adversarial defense performance. These methods are classifier and
attack-agnostic, making them versatile but often computationally intensive.
Recent strides in diffusion and score networks have improved image generation
and, by extension, adversarial purification. Another highly efficient class of
adversarial defense methods known as adversarial training requires specific
knowledge of attack vectors, forcing them to be trained extensively on
adversarial examples. To overcome these limitations, we introduce a new
framework, namely Language Guided Adversarial Purification (LGAP), utilizing
pre-trained diffusion models and caption generators to defend against
adversarial attacks. Given an input image, our method first generates a
caption, which is then used to guide the adversarial purification process
through a diffusion network. Our approach has been evaluated against strong
adversarial attacks, proving its effectiveness in enhancing adversarial
robustness. Our results indicate that LGAP outperforms most existing
adversarial defense techniques without requiring specialized network training.
This underscores the generalizability of models trained on large datasets,
highlighting a promising direction for further research.

通过使用生成模型进行对抗性净化，可以展示出很强的对抗性防御性能。我们介绍了一种新的框架，即语言引导对抗净化（LGAP），利用预训练的扩散模型和字幕生成器来防御对抗性攻击。通过生成图像的字幕，我们的方法首先生成一个字幕，然后通过扩散网络来指导对抗性净化过程。我们的方法在对抗性攻击下经过评估，证明了其提高对抗性鲁棒性的有效性。我们的结果表明，LGAP 的性能优于大多数现有的对抗性防御技术，而不需要专门的网络训练，突显了在大规模数据集上训练的模型的广泛适用性，为进一步的研究方向提供了有希望的方向。