Signature verification system and method of manufacturing a document for an authorized user.

摘要

Signature verification systems are disclosed which include documents each of which bears a cryptographic representation of a function of a position-invariant transform of a reference signature of an authorized user thereof. On some of these documents the cryptographic representation is a digital image of a logarithmic function of the Fourier spectrum of the reference signature displayed as an intensity function the pixels of which have been recollocated in accordance with a cryptokey which is represented on the document. Apparatus (24) are disclosed for use in producing such cryptographic representations on documents. Apparatus (36) are disclosed for verifying documents bearing such cryptographic representations and also bearing specimens of the corresponding reference signatures. Methods of signature verification using documents bearing such cryptographic representations and specimens of said reference signatures are also disclosed.