National Instruments IMAQ Vision, User Manual

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Contents
© National Instruments Corporation vii IMAQ Vision for LabWindows/CVI User Manual
Training the Color Pattern Matching Algorithm...............................5-20
Defining a Search Area .....................................................................5-21
Setting Matching Parameters and Tolerances ...................................5-22
Testing the Search Algorithm on Test Images..................................5-24
Finding Points Using Color Location..............................................................5-25
Convert Pixel Coordinates to Real-World Coordinates.................................................5-26
Make Measurements ......................................................................................................5-26
Distance Measurements...................................................................................5-26
Analytic Geometry Measurements ..................................................................5-27
Instrument Reader Measurements ...................................................................5-27
Display Results ..............................................................................................................5-28
Chapter 6
Calibration
Perspective and Nonlinear Distortion Calibration .........................................................6-1
Defining a Calibration Template .....................................................................6-2
Defining a Reference Coordinate System .......................................................6-2
Learning Calibration Information....................................................................6-5
Specifying Scaling Factors................................................................6-6
Choosing a Region of Interest...........................................................6-6
Choosing a Learning Algorithm .......................................................6-6
Using the Learning Score..................................................................6-7
Learning the Error Map.....................................................................6-8
Learning the Correction Table ..........................................................6-8
Setting the Scaling Method ...............................................................6-8
Calibration Invalidation ....................................................................6-8
Simple Calibration .........................................................................................................6-9
Save Calibration Information.........................................................................................6-10
Attach Calibration Information......................................................................................6-10
Appendix A
Technical Support Resources
Glossary
Index