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Smart Camera / Vision-Sensor / 1D-/2D-Code-Scanner / OCR Reader
Property
Unused Error
Correction
As data codes are redundant codes, errors in the modules
or codewords can be corrected. The amount of error cor-
recting capacities which is not already used by the present
data code symbol is expressed in the Unused Error Cor-
rection quality. In a way, this grade reflects the reliability of
the decoding process. Note, that even codes with an Un-
used Error Correction grading of 0, which could possibly
mean a false decoding result, can be decoded in a reliable
way, because the implemented decoding functionality is
more sophisticated and robust compared to the reference
decode algorithm proposed by the standard
The following results appear after quality testing in accordance with DPM-1-2006
The evaluation of code quality is specified as a number between 0 and 4, 0 being the
worst and 4 the best evaluation.
Quality AIM
DPM-1-2006
Overall Quality
Minimum of all individual grades
Cell Contrast
Range between minimum and maximum pixel intensity in
the data code domain. A strong contrast results in a good
grading
Cell Modulation
Indicates how strong the amplitudes of the data code
modules are. Big amplitudes make the assignment of the
modules to black or white more certain, resulting in a high
modulation grade. It is to note that the computation of the
modulation grade is influenced by the specific level of er-
ror correction capacity, meaning that the modulation de-
grades less for codes with higher error correction capacity
Fixed Pattern
Damage
Degradation or damage of the fixed pattern, or the respec-
tive quiet zones, is assessed with the Fixed Pattern Dam-
age quality
Decode
Always takes the grade 4, meaning that the code could
be decoded
Axial Nonunifor-
mity
Due to a potentially oblique view of the camera onto the
data code or a defective fabrication of the data code itself,
the width to height ratio can be distorted. This deterioration
results in a degraded Axial Nonuniformity
Grid
Nonuniformity
If apart from an affine distortion the data code is subject to
perspective or any other distortions too this degrades the
Grid Nonuniformity quality
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