METHOD AND DEVICE FOR IDENTIFYING A TWO-DIMENSIONAL BARCODE

摘要

A method of identifying a two-dimensional bar code in digital image data of the bar code, the bar code comprising first and second type elements arranged in an ordered grid and having an outline that comprises an L-shape clock line with transitions between the first and second type elements and an L-shape solid line without transitions between the first and second type elements, wherein approximate corners in the digital image data determine a first and a second pair of opposite edge segments along the outline, the method comprising scanning in the digital image data a first edge segment of the first pair and counting transitions between the first and second type elements along the first edge segment of the first pair; if no transitions were counted along the first edge segment of the first pair, then scanning in the digital image data the second edge segment of the first pair and counting transitions between the first and second type elements along the second edge segment of the first pair; scanning in the digital image data a first edge segment of the second pair and counting transitions between the first and second type elements along the first edge segment of the second pair; if no transitions were counted along the first edge segment of the second pair, then scanning in the digital image data the second edge segment of the second pair and counting transitions between the first and second type elements along the second edge segment of the second pair; identifying the edge segment of the first pair and the edge segment of the second pair along which transitions were counted as the L-shape clock line of the bar code, and identifying the edge segment of the first pair and the edge segment of the second pair along which no transitions were counted as the L-shape solid line of the bar code.

主权项

1. A method of identifying a two-dimensional bar code in digital image data of the bar code, the bar code comprising first and second type elements arranged in an ordered grid and having an outline that comprises an L-shape clock line with transitions between the first and second type elements and an L-shape solid line without transitions between the first and second type elements, wherein approximate corners in the digital image data determine a first and a second pair of opposite edge segments along the outline, the method comprising:
scanning in the digital image data a first edge segment of the first pair and counting transitions between the first and second type elements along the first edge segment of the first pair; if no transitions were counted along the first edge segment of the first pair, then scanning in the digital image data the second edge segment of the first pair and counting transitions between the first and second type elements along the second edge segment of the first pair; scanning in the digital image data a first edge segment of the second pair and counting transitions between the first and second type elements along the first edge segment of the second pair; if no transitions were counted along the first edge segment of the second pair, then scanning in the digital image data the second edge segment of the second pair and counting transitions between the first and second type elements along the second edge segment of the second pair; identifying the edge segment of the first pair and the edge segment of the second pair along which transitions were counted as the L-shape clock line of the bar code, and identifying the edge segment of the first pair and the edge segment of the second pair along which no transitions were counted as the L-shape solid line of the bar code.