1. A method, comprising: generating, based upon a unique, plaintext data from a transaction document for a sales transaction: a unique password for data encryption; and a unique finger-print shuffling sequence; receiving a first fingerprint image and a second fingerprint image from a respective first and second party to the sales transaction; encrypting the unique plaintext data with the unique password to generate a ciphertext data; generating a first two-dimensional two-color barcode (2-D barcode) representing the plaintext unique data, wherein the first 2-D barcode comprises a light color and a dark color; generating a second two-dimensional two-color barcode (2-D barcode) representing the ciphertext data, wherein the second 2-D barcode comprises the light color and the dark color; merging the first 2-D barcode and the second 2-D barcode into a merged multicolored 2-D barcode, wherein each distinct color of the multicolored 2-D barcode represents a designated combination of two light-colored cells, two dark-colored cells, a dark-colored cell and a light-colored cell, or a light-colored celled and a dark-colored cell from the first 2-D barcode and the second 2-D barcode; dividing each of the first fingerprint image and the second fingerprint image into a respective plurality of first image parts and second image parts; spatially shuffling each of the first plurality of image parts and the second plurality of image parts to generate a respective first shuffled fingerprint image and a second shuffled fingerprint image, wherein said spatial shuffling is in accordance with the unique finger-print shuffling sequence; merging the first shuffled fingerprint image and the second shuffled fingerprint image into a combined shuffled fingerprint image; and concatenating the merged multicolored 2-D barcode and the combined shuffled fingerprint image into a final transaction document image.