Patent ID: 8047447
Filing Date: 2011-11-01
Classification: G06K

Abstract:
1. A method for encoding data in a color barcode pattern, the method comprising: receiving a message to be embedded in a color barcode pattern, said message comprising a plurality of single data values, each single data value having only one unique state from a set of possible state values; assigning a major axis of each orientation direction of a substantially elliptical dot to a unique state of said set of state values,said major axis being relative to a horizontal and vertical axis of said barcode; selecting colorants to render said color barcode pattern, said colorants based upon a spectral sensitivity of the color channels of a device used to scan said barcode and having sustantially non-overlapping absorbtion spectra such that the absorption bands of said selected colorants do not interfere with each other and cause unwanted absorptions in the spectra of a color print; associating said orientation directions with each colorant such that there exists a one-to-one correspondence between unique states and colorant/orientation-direction combination such that a colored dot is only printed in one of the possible orientation directions defined for that particular colorant; and producing a color barcode pattern encoded with said received message by superimposing layers of individual patterns of colorants on a common substrate, said superimposing comprising for each of said selected colorant layers: dividing an image pattern of said colorant into a tiling of periodic tiles based upon a spatial extent of said image; associating each tile with a single data value; and for each tile in said tiling wherein a single data value is to be endcoded: generating a substantially elliptical dot wherein said substantially elliptical dot's major axis orientation corresponds to the unique state of said single data value; and printing said oriented dot in said tile using said colorant.