Chapter 5
Performing Machine Vision Tasks
IMAQ Vision for LabWindows/CVI User Manual
5-14
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Symmetry
A rotationally symmetric template, shown in Figure 5-7a, is less sensitive
to changes in rotation than one that is rotationally asymmetric, shown in
Figure 5-7b. A rotationally symmetric template provides good positioning
information but no orientation information.
Figure 5-7.
Symmetry
Feature Detail
A template with relatively coarse features, shown in Figure 5-8a, is less
sensitive to variations in size and rotation than a model with fine features,
Figure 5-8b. However, the model must contain enough detail to identify the
feature.
Figure 5-8.
Feature Detail
a.
b.
a.
b.
