Cognex DataMan Communications And Programming Manual page 39

Property
symbolContrast
cellContrast
Type 1D Standards
Metric 1D Readability, ISO/IEC
15416
Metric
39
DataMan Application Development
2D Standards
ISO/IEC 15415
(DataMatrix, QR,
DotCode), SEMI T10
AIM/DPM ISO/IEC TR-
29158 (DataMatrix, QR)
Description
The contrast of the
symbol in ISO15415.
Symbol contrast is a
measure of the
difference in
grayscale value
between the light and
dark cells. A high
contrast makes the
code easier to
decode, while a code
with low contrast may
not decode well due
to difficulty separating
the light and dark
cells from each other.
A poor contrast might
indicate poor lighting,
a code which is
difficult to read due to
similarities between
the print and the
background, or that a
printer is performing
poorly.
The contrast of the
cell. Cell contrast is a
measure of the
difference in
grayscale value
between the light and
dark parts of the cell.
A high contrast makes
the code easier to
decode, while a code
with low contrast may
not decode well due
to difficulty separating
the light and dark
areas of the cells. A
poor contrast might
indicate poor lighting,
a code which is
difficult to read due to
similarities between
marked and
unmarked areas.