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Bar Code Failures
The ODV-2D tells the printer to announce a fault condition in two situations:
•
When the validator detects a bad bar code
•
When the validator detects no bar code where it expects to find one.
How the printer reacts to these faults is determined by the printer’s configuration settings, as described
in
this section.
Process for 1-D Barcode Analysis
The following flow chart in Figure 5 is an overview of how the ODV-2D performs the 1-D barcode analysis.
Edge Determination
Symbol contrast >= Sym-
bol contrast Threshold
Grading Scale:
A: >= 70%
B: >= 55%
C: >= 40%
D: >= 20%
F: < 20%
Reflectance Minimum <=
Threshold percentage of
Reflectance Maximum
Min. Edge Contrast (worst
pair) >= Min. Edge Contrast
Threshold
Modulation >= Modulation
Threshold
Grading Scale:
A: >= 70%
B: >= 60%
C: >= 50%
D: >= 40%
F: < 40%
Defects <= Defects
Threshold
Grading Scale:
A: <= 15%
B: <= 20%
C: <= 25%
D: <= 30%
F: < 30%
Decodeability >= De-
codeability Threshold
Grading Scale:
A: >= 62%
B: >= 50%
C: >= 37%
D: >= 25%
F: < 25%
Percent Decode >= Per-
cent Decode Threshold
Overall Grade >= Overall
Grade Threshold
Grading Scale:
A: 3.5 to 4.0
B: 2.5 to 3.4
C: 1.5 to 2.4
D: 0.5 to 1.4
F: 0.0 to 0.4
Figure 5 1-D Barcode Analysis