| CPC G06F 21/16 (2013.01) [G06K 19/06075 (2013.01); G07D 7/004 (2013.01)] | 8 Claims |
|
1. A method of authenticating human readable textual characters provided together with machine-readable representation of error correction data on a support, comprising the steps of:
securing textual data against forgery and tampering, comprising the steps of:
storing in a memory of a processing unit a textual data block containing a digital representation of a given finite set of textual characters of the textual data;
processing with the processing unit the digital representation of textual characters of the stored textual data block with an error correction code programmed in the processing unit to generate error correction data in a corresponding error correction data block;
formatting the textual data block and the error correction data block with the processing unit to respectively provide, in a human readable textual data block, a human readable representation of the textual characters of the textual data block and, in a machine-readable error correction data block, a machine-readable representation of the error correction data of the error correction data block separate from the human readable representation of the textual characters of the textual data block, to obtain a corresponding authenticatable textual data block comprising said human readable textual data block and said machine-readable error correction data block; and
(i) displaying human readable textual characters and corresponding machine-readable representation of error correction data of the obtained authenticatable textual data block on the support being a display connected to the processing unit, or
(ii) marking on the support being a substrate, via a marking device connected to the processing unit and equipped with a control unit operable to control the operation of marking based on data received from the processing unit, human readable textual characters and corresponding machine-readable representation of error correction data of the obtained authenticatable textual data block received from the processing unit,
thereby providing on the support authentication data comprising the human readable textual characters and the corresponding machine-readable error correction data;
scanning with a scanner, equipped with an imaging unit, a scanner processing unit having a scanner memory and connected to a scanner display, the human readable textual characters on the support to obtain, via image processing of the scanned human readable textual characters, a scanned textual data block being a digital representation of said scanned human readable textual characters;
scanning with the scanner machine-readable representation of error correction data on the support to obtain, via machine-readable decoder programmed on the scanner processing unit, corresponding scanned error correction data in a scanned error correction data block, the scanned error correction data block being a digital representation of said scanned error correction data;
correcting the scanned textual data block with an error correction code programmed on the scanner processing unit using the scanned error correction data of the scanned error correction data block to obtain a corresponding corrected scanned textual data block;
displaying a visual representation of the corrected scanned textual data block as corresponding corrected human readable textual characters on the scanner display and comparing the displayed visual representation of the corrected scanned textual data block with the human readable textual characters provided on the support; and
detecting any alteration or fraud when the displayed visual representation of the corrected scanned textual data block is different from the human readable textual characters as a result of the comparison;
wherein the human readable textual characters and the machine-readable error correction data on the support have been generated by calculating with a hash function programmed on the processing unit a hash value of any portion of a data block resulting from a concatenation of the textual data block and the error correction data block; and storing the calculated hash value as a reference hash value in a ledger, the hash function being programmed on the scanner processing unit, and the scanner being connected to a scanner communication unit operable to communicate via a communication link with the ledger, the method comprising the further steps of:
calculating with a hash function programmed on the processing unit a hash value of any portion of a data block resulting from a concatenation of the textual data block and the error correction data block; and storing the calculated hash value as a reference hash value in a ledger, with the hash function programmed on the scanner processing unit a scan hash value of the corrected scanned textual data block, or the scanned error correction data block, or any portion of a data block resulting from a concatenation of the corrected scanned textual data block and the scanned error correction data block;
obtaining the reference hash value stored in the ledger via the scanner communication unit and the communication link, and checking whether the obtained reference hash value matches the scan hash value; and
(e) indicating a result of the checking operation, or
(f) storing a result of the checking operation in the scanner memory.
|