National Instruments IMAQ Vision, User Manual

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Chapter 5 Machine Vision
IMAQ Vision for LabWindows/CVI User Manual 5-22 ni.com
Figure 5-12. Selecting a Search Area for Color Pattern Matching
The time required to locate a pattern in an image depends on both the
template size and the search area. By reducing the search area or increasing
the template size, you can reduce the required search time.
Setting Matching Parameters and Tolerances
Every color pattern matching algorithm makes assumptions about the
images and color pattern matching parameters used in machine vision
applications. These assumptions work for a high percentage of the
applications.
In some applications, the assumptions used in the algorithm are not
optimal. In such cases, you must modify the color pattern matching
parameters. Knowing your particular application and the images you want
to process is useful in selecting the pattern matching parameters. Use the
options parameter of
imaqMatchColorPattern()
to set these elements.
1 Search Area for 20 Amp Fuses 2 Search Area for 25 Amp Fuses
1 2