1. A method of encoding a document with account signature data for signature validation, the method comprising the steps of: compressing the account signature data to a fingerprint comprising machine-readable readable data corresponding to one or more account signatures, the fingerprint comprising a one-dimensional skeletonized version of account signature data containg 100 bytes of information or less, evaluating the complexity and topology of each account signature; encoding the fingerprint into a barcode; printing the barcode on the document; and determining a person-specific confidence threshold for each account signature based upon the complexity and topology of each account signature.