The standard for 1-D label-based codes
The verification standard for 1-D codes, ISO 15416, requires 10 individual scan lines be taken throughout the height of a code and a grade assigned to each scan line. Scan line grades are determined by testing seven different parameters; the lowest graded parameter becomes the overall grade for the individual scan line. The formal grade is formulated by taking the average of all of the individual line scan grades.
The first three parameters—minimum reflectance, decode, and minimum edge contrast-- are graded as pass or fail. If a scan line fails minimum reflectance, decode or minimum edge contrast, the line will automatically receive an “F” grade. If all three pass, the software moves on to grade symbol contrast, modulation, defects, and decodability parameters. Each are graded on a scale of A to F. Once every scan line has been graded, the ten scans are averaged to generate a formal grade for the barcode.
ISO/IEC 15416 Quality Parameters
|Minimum Reflectance checks whether the bars are dark enough to meet the required ratio of light that is reflected off of the spaces.||
Bars too light
|Edge Contrast measures the difference between adjacent bars and spaces.||
Background too dark
|Modulation refers to local variations in contrast.||
|Decode checks to see whether the code can be read using the standard reference decode algorithm.||
Symbol read? Y/N
|Defects include printing errors, dirt, or markings that affect one single bar or space.||
|Decodability grades the accuracy of bar and space widths compared to their ideal size. A barcode with bar width growth or distortion will score a low decodability grade.||
Bar Width Growth/Loss or Distortion
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