National Instruments IMAQ Vision for Measurement Studio - Manual (Page 74)

Chapter 5 Machine Vision
IMAQ Vision for LabWindows/CVI User Manual 5-28 ni.com
Use imaqFindLCDSegments() to calculate the regions of interest around
each digit in an LCD or LED. To find the area of each digit, all the segments
of the indicator must be activated. Use
imaqReadLCD() to read multiple
digits of an LCD or LED.
Use imaqReadBarcode() to read values encoded in 1D barcodes. First,
specify a region of interest that encloses the barcode information, and
specify the type of barcode. Then, read the barcode.
Display Results
You can display the results obtained at various stages of you inspection
process on the window that displays your inspection image. You can do
this by overlaying information on an image. The software attaches the
information that you want to overlay to the image, but it does not modify
the image. The overlay appears every time you display the image in an
external window.
Use the following functions to overlay search regions, inspection results,
and other information, such as text and bitmaps.
• imaqOverlayPoints() —Overlays points on an image. Specify a
point by its x-coordinate and y-coordinate.
• imaqOverlayLine() —Overlays a line on an image. Specify a line
by its start and end points.
• imaqOverlayRect() —Overlays a rectangle on an image.
• imaqOverlayOval() —Overlays an oval or a circle on the image.
• imaqOverlayArc() —Overlays an arc on the image.
• imaqOverlayMetafile() —Overlays a metafile on the image.
• imaqOverlayText() —Overlays text on an image.
• imaqOverlayROI() —Overlays an ROI on an image.
• imaqOverlayClosedContour() —Overlays a closed contour on an
image.
• imaqOverlayOpenContour() —Overlays an open contour on an
image.
To use these functions, pass in the image on which you want to overlay
information and the information that you want to overlay. You can select the
color of overlays by using the above functions.