Automatic Signature Verification (ASV)
Definition
Algorithmic systems that compare a questioned signature against a reference set using extracted biometric features (stroke curvature, velocity profile, pressure distribution). Designed against skilled human forgeries; GAN-generated forgeries may defeat ASV by optimising against the same feature distributions.
Related terms
- Adversarial Attack
- In AI detection contexts, a forgery specifically constructed to defeat a trained detector by incorporating small perturbations that cause the detector's classifier...
- C2PA (Coalition for Content Provenance and Authenticity)
- An open technical standard that embeds cryptographically signed provenance assertions into media files at the point of capture or editing. A C2PA...
- Content-Aware Fill
- An image editing feature (Photoshop from CS5; AI-driven from version 22.0) that replaces a masked region with synthesised pixel content matching the...
- Diffusion Model
- A generative neural network architecture (Ho et al., 2020; Stable Diffusion, Rombach et al., 2022) that learns to reverse a noise-addition process...
- ESDA (Electrostatic Detection Apparatus)
- A non-destructive technique for detecting indented impressions on paper caused by writing pressure. A physical ink signature on paper produces detectable ESDA...
- GAN (Generative Adversarial Network)
- A neural architecture introduced by Goodfellow et al. (2014) consisting of a generator and discriminator trained in opposition. The generator learns to...
- GAN Spectrum Fingerprint
- Periodic artefacts in the Fourier frequency spectrum of images generated by GAN architectures with upsampling layers. First reported by Zhang et al....
- JUMBF (JPEG Universal Metadata Box Format)
- A container format (ISO/IEC 19566-5) used by the C2PA specification to embed provenance manifest data within JPEG image files. The JUMBF box...
- PRNU (Photo Response Non-Uniformity)
- The unique pattern of pixel-level sensitivity variations in a camera sensor, used as a device fingerprint. A genuine camera-original image carries the...
Explained in
- AI-Generated Documents, Deepfake Signatures and Image ManipulationAlgorithmic systems that compare a questioned signature against a reference set using extracted biometric features (stroke curvature, velocity profile, pressur...