Unraveling Hidden Representations: A Multi-Modal Layer Analysis for Better Synthetic Content Forensics

TMLR Paper3909 Authors

08 Jan 2025 (modified: 19 Mar 2025)Rejected by TMLREveryoneRevisionsBibTeXCC BY 4.0
Abstract: Generative models achieve remarkable results in multiple data domains, including images and texts, among other examples. Unfortunately, malicious users exploit synthetic media for spreading misinformation and disseminating deepfakes. Consequently, the need for robust and stable fake detectors is pressing, especially when new generative models appear everyday. While the majority of existing work train classifiers that discriminate between real and fake information, such tools typically generalize only within the same family of generators and data modalities, yielding poor results on other generative classes and data domains. Towards a “universal” classifier, we propose the use of large pre-trained multi-modal models for the detection of generative content. Effectively, we show that the latent code of these models naturally captures information discriminating real from fake. Building on this observation, we demonstrate that linear classifiers trained on these features can achieve state-of-the-art results across various modalities, while remaining computationally efficient, fast to train, and effective even in few-shot settings. Our work primarily focuses on fake detection in audio and images, achieving performance that surpasses or matches that of strong baseline methods.
Submission Length: Regular submission (no more than 12 pages of main content)
Assigned Action Editor: ~Yixuan_Li1
Submission Number: 3909
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