IMAQ Match Pattern 4 VI can lose some matches with an appropriate score when used with some advanced options (Max Pyramid Level, Match List Reduction Factor).
This bug is somewhat similar to CAR #718023 listed in Known VDM Issues (archived), but relates to Pattern Matching rather than Geometric Matching.
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Environment:
Windows 8.1
LabVIEW 2018 SP1 f4 - 2020
Vision Development Module 2018 SP1 - 2020
Steps to Reproduce:
- Download all attached files and open the VI;
- Run the VI and make sure there is a match found with score of 866;
- Increase the Minimum Match Score parameter value to 550 (you can scroll the mouse wheel up over the field);
- Run the VI.
Expected Result:
The match with a score of 866 is still found.
Actual Result:
No matches found.
Workaround:
Change one of the following advanced options:
- Lower the value of Max Pyramid Level;
- Lower the value of Match List Reduction Factor;
- Set Process Border Matches option to 1 (True).
Reported to NI with SR #7812156.
