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.
- Features used
- Stroke curvature, velocity, pressure
- Designed against
- Skilled human forgeries
- Known weakness
- GAN-generated forgeries may defeat it
Common questions
Why can GAN-generated forgeries defeat ASV when human forgers usually fail?+
A GAN can be trained directly against the same biometric feature distributions ASV extracts, effectively optimizing the forgery to satisfy the detector rather than just visually resembling the signature.
Does ASV replace a human questioned-document examiner in casework?+
No. It is generally used as an automated screening or supporting tool, with a qualified examiner still performing the comparison and forming the expert opinion presented in a report or testimony.
Related terms
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- Diffusion Model
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- ESDA (Electrostatic Detection Apparatus)
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- GAN (Generative Adversarial Network)
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- GAN Spectrum Fingerprint
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- JUMBF (JPEG Universal Metadata Box Format)
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