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Smart Camera / Vision-Sensor / 1D-/2D-Code-Scanner / OCR Reader
Threshold Low /
Threshold High
The lower and upper gray-scale threshold values can be set in
the static mode:
a) The lower threshold is less than the upper threshold.
• Pixels with gray-scale values between the two thresholds
appear white.
• Pixels with gray-scale values which fall short of the lower
threshold or exceed the upper threshold appear black.
b) The lower threshold is greater than the upper threshold.
• Pixels with gray-scale values between the two thresholds
appear black.
• Pixels with gray-scale values which fall short of the upper
threshold or exceed the lower threshold appear white.
Note: The profile and the histogram (see sections 10.2.3.3 and
10.2.3.4), which show the gray-scale values and their distribu-
tion, simplify the specification of the lower and upper gray-scale
threshold values. For example, the limit values at both sides of
the edges can also be specified by means of the profile, and
the thresholds can be accordingly adjusted. Histogram calcula-
tion is carried out for the entire image and is not restricted to a
single region.
Quantile 1 /
Quantile 2
Quantiles 1 and 2 are required for adaptive adjustment in the
histogram:
• Quantile 1 specifies how many values from the gray-scale
value distribution should be less that the lower gray-scale
threshold value as a percentage from the bottom up.
• Quantile 2 specifies how many values from the gray-scale
value distribution should be greater that the upper gray-
scale threshold value as a percentage from the top down.
Offset
Offset can be adjusted by means of the adaptive setting with
histogram and reference.
With the help of the offset, the settings for the lower and upper
gray-scale threshold values are shifted either up or down by an
amount equal to the offset.
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