PP-Mark anchored image watermarking to a zero-knowledge proof so forgeries fail verification by construction
AspireAI community · arXiv
As generated images become indistinguishable from real ones, provenance matters, but watermarking schemes weaken once their detector is public and can be attacked. PP-Mark anchors lightweight statistical detection to a zero-knowledge proof of the embedding process, which is what makes forgery fail full verification by construction rather than by defeating a classifier. The paper establishes formal unforgeability under standard cryptographic assumptions and validates the approach against representative baselines on two latent-diffusion models, SD2.1 and SDXL, showing resistance to black-box imprint forgery, white-box optimisation and regeneration attacks while staying practical for decentralised verification. The limitation is scope: this is a watermarking scheme for generative image models, evaluated on two of them, and the formal guarantee applies to the embedding step it proves rather than to content authenticity in general.
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