ISO/IEC 15415

The standard for 2-D label-based barcodes

For 2-D barcodes, barcode verifiers analyze the structure of the symbol and the reflectance of each of the modules. 2-D label-based codes are graded according to eight different parameters under the ISO 15415 standard. Like with 1-D barcodes, some parameters are image-related, and others are data-related. Because 2-D barcodes contain so much more data than 1-D barcodes, there are more parameters related to data quality than image quality.

Grading

The lowest individual parameter grade becomes the overall grade for the code. The grading process begins with a pass/fail test. If the code can be decoded, it passes the first test. If it cannot, it is automatically assigned an “F” grade. After a code is decoded, it is graded for symbol contrast, modulation, reflectance margin, fixed pattern damage, axial non‐uniformity, grid non‐uniformity, and unused error correction.

ISO/IEC 15415 Quality Perameters

Symbol Contrast refers to the difference between the darkest and the lightest modules.
Modulation measures local variations in contrast.
Fixed Pattern Damage includes errors with the L sides or clock pattern or quiet zone.
Axial Non-uniformity refers to the uneven scaling of the code.
Grid Non-uniformity measures the biggest deviation from the grid.