National Instruments IMAQ Vision for Measurement Studio - Manual (Page 30)

Chapter 3 Grayscale and Color Measurements
IMAQ Vision for LabWindows/CVI User Manual 3-4 ni.com
Figure 3-2. ROI Constructor
2. Select an ROI tool from the tools palette.
3. Draw an ROI on your image. Resize and reposition the ROI until it
designates the area you want to inspect.
4. Click the OK button to output a descriptor of the region you selected.
You can input the ROI descriptor into many analysis and processing
functions. You can also convert the ROI descriptor into an image mask,
which you can use to process selected regions in the image. Use
imaqROIToMask() to convert the ROI descriptor into an image mask.
The tools palette, shown in Figure 3-3, automatically transforms from the
palette on the left to the palette on the right when you manipulate an ROI
tool in an image window. The palette on the right displays the
characteristics of the ROI you are drawing.