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Chapter 6
Calibrating Images
6-10
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Figure 6-7.  Defining a Simple Calibration
Save Calibration Information
After you learn the calibration information, you can save it so that you 
do not have to relearn the information for subsequent processing. Use 
CWIMAQVision.WriteImageAndVisionInfo
 to save the image of 
the grid and its associated calibration information to a file. To read the 
file containing the calibration information use 
CWIMAQVision.ReadImageAndVisionInfo
. For more information 
about attaching the calibration information you read from another image, 
refer to thAttach Calibration Information section.
Attach Calibration Information
When you finish calibrating the setup, you can apply the calibration 
settings to images that you acquire. Use 
CWIMAQVision.SetCalibrationInformation
 to attach the 
calibration information of the current setup to each image you acquire. 
This method takes in a source image containing the calibration information 
and a destination image that you want to calibrate. The output image is the 
inspection image with the calibration information attached to it.
Using the calibration information attached to the image, you can 
accurately convert pixel coordinates to real-world coordinates to 
make any of the analytic geometry measurements with 
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Origin
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Y
dy
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