Hardware manual

Impact Reference Guide Character Contour Match
3-163 Datalogic Automation Inc.
If symbols are printed on transparent parts, or imaged on the opposite side of the printing, there can be a
reflection. The contrast difference of symbols printed dark on light or light on dark will not affect the decod-
ing.
The tool provides the string decoded from the symbol and a list of points indicating the found modules, as
outputs. For more details, see “How the Data Matrix tool works” on page 3-165.
A Setup is available for this tool. See “How to set up the Data Matrix tool” on page 3-164 for more details.
Input Name What it is
Input Image The image to be inspected
Tool Origin The tool’s origin relative to the entire image space.
Find Shape List The area of the image to search
Shape List ROI
Type
Each Shape is separate ROI: Each shape is processed as a separate
ROI and the results are combined. This mode is faster than the other
mode if the shapes are far apart, but results are duplicated if the shapes
overlap.
ShapeList is One ROI: The ShapeList is one large rectangular ROI and
the shapes are the enabled pixels within the rectangle. The tool may be
slow if the shapes are far apart. This setting allows shapes to overlap
and form complex shapes without repeating the overlapped pixels and
duplicating results.
Module Size In Pix-
els
If you enter a number in this property, then the tool uses it to find the
symbol more quickly and reliably.
If you leave the default value of 4 pixels, the tool automatically looks for
symbols with modules of various sizes, 4, 8, 12, … If you enter a differ-
ent module size, then the tool only looks for codes with modules of that
size. The minimum recommended module size is 3 pixels.
Enable Boundary
and Module Out-
puts
If True, the Found Modules and Symbol Boundary outputs are active.
This property is mainly intended for troubleshooting during tool setup.
See “How the Data Matrix tool works” on page 3-165.
Decode Nonprint-
able Characters As
Hex
When True, the exact value of all non-Ascii output bytes is displayed in
the Symbol String output. Useful for debugging symbols during tool
setup that include non-Ascii characters. Should normally be set to False.
Verify String If this string matches the decoded data matrix string, the Successful
Read output is set to True. If the string is empty, no verification is per-
formed.
Verify Wildcard
Char
If this wildcard character is present in the Verify String, it is used as a
placeholder for one letter or symbol.
Threshold Method Adaptive Threshold: see “Blob Threshold Method” on page 3-109
Fixed Threshold: The threshold is fixed at the Fixed Threshold property
value
Fixed Threshold When Threshold Method is Fixed Threshold, this is the grey level thresh-
old value the tool will use when it runs.