Patent ID: 8393542

Claim:
A method for reading stacked bar code information by processing image data obtained through capturing the stacked bar code information recorded in a medium, comprising: utilizing an apparatus for reading stacked bar code information to perform: a column identifying process for identifying a border part of columns of the stacked bar code information on the basis of the image data captured and obtained; a border determining process for determining a column border in each row of the stacked bar code on the basis of the border part of columns identified by the column identifying process; and a code word obtaining process for code word conversion by using the image data of an extent of each column on the basis of a result of the border determining process; wherein the code word obtaining process has a plurality of conversion processes for creating line width matrices through measurement of the line width of bars and spaces of each column of the image data, by using each of a plurality of threshold methods; and wherein a cluster number according to a line width matrix calculated through one of the plurality of conversion processes is compared to a theoretical value of a cluster number of each row.