ResearchResearch paperComputer Vision1 source · Oct 21, 2026

Beyond Shortcut Learning: Hierarchical Spatial Prototype Regularization for Face Forgery Detection

Leveraging this insight, we propose Hierarchical Spatial Prototype (HSP) regularization, which explicitly models the forgery manifold by learning a structured prototype subspace over spatial features.

Key points

  • Recent advances in generative models have enabled highly realistic face forgeries, yet generalizing deepfake detectors to unseen manipulation pipelines remains a major challenge.
  • In this paper, we provide new evidence that naively fine-tuned vision models suffer from severe forensic representation collapse: their extracted cues are often entangled with unstable, dataset-specific artifacts, resulting in structurally fragile representations and poor cross-domain generalization.
  • We further introduce prototype orthogonality and second-order assignment balance, which jointly preserve the geometric independence of latent forgery factors and promote high-effective-rank utilization of the forensic representation, thereby reducing reliance on dataset-specific shortcuts.
  • These results demonstrate the practical value of HSP as an easy-to-adopt regularization module for enhancing deepfake detectors.

Sources (1)

  • [1]Beyond Shortcut Learning: Hierarchical Spatial Prototype Regularization for Face Forgery Detection
    arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 21, 09:02 AM
    Leveraging this insight, we propose Hierarchical Spatial Prototype (HSP) regularization, which explicitly models the forgery manifold by learning a structured prototype subspace over spatial features.
    Recent advances in generative models have enabled highly realistic face forgeries, yet generalizing deepfake detectors to unseen manipulation pipelines remains a major challenge.

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