Display Results

You can overlay the results obtained at various stages of your inspection process on the inspection image. NI Vision attaches the information that you want to overlay to the image, but it does not modify the image. You also can group similiar types of overlay information together to allow multiple overlays to act as a single overlay. Overlays appear every time you display the image.

Use the following VIs to set or view the properties of image overlays.

• IMAQ Set Overlay Properties—Sets the overlay properties for an image.
• IMAQ Get Overlay Properties—Gets the overlay properties for an image.

Use the following VIs to overlay search regions, inspection results, and other information, such as text and bitmaps.

• IMAQ Overlay Points—Overlays points on an image. Specify a point by its x-coordinate and y-coordinate.
• IMAQ Overlay Line—Overlays a line on an image. Specify a line by its start and end points.
• IMAQ Overlay Multiple Lines—Overlays multiple lines on an image.
• IMAQ Overlay Rectangle—Overlays a rectangle on an image.
• IMAQ Overlay Oval—Overlays an oval or a circle on the image.
• IMAQ Overlay Arc—Overlays an arc on the image.
• IMAQ Overlay Bitmap—Overlays a bitmap on the image.
• IMAQ Overlay Text—Overlays text on an image.
• IMAQ Overlay ROI—Overlays an ROI described by the ROI Descriptor on an image.

To use these VIs, pass in the image on which you want to overlay information and the information that you want to overlay.

Tip  You can select the color of the overlays using the previous VIs.

You can configure the following processing VIs to overlay different types of information about the inspection image:

• IMAQ Edge
• IMAQ Find Circular Edge
• IMAQ Find Straight Edges
• IMAQ Find Concentric Edge
• IMAQ Clamp Horizontal Max
• IMAQ Clamp Horizontal Min
• IMAQ Clamp Vertical Max
• IMAQ Clamp Vertical Min
• IMAQ Find Pattern 2
• IMAQ Count Objects 2
• IMAQ Find CoordSys (Rect) 2
• IMAQ Find CoordSys (2 Rects) 2
• IMAQ Find CoordSys (Pattern) 2

The following list contains the kinds of information you can overlay on the previous VIs:

• Search area input into the VI
• Search lines used for edge detection
• Edges detected along the search lines
• Bounding rectangle of particles
• Center of particles
• Result of the VI

Select the information you want to overlay by enabling the corresponding Boolean control of the VI.

Use the IMAQ Clear Overlay VI to clear any previous overlay information from the image. Use the IMAQ Write Image and Vision Info File 2 instance of the IMAQ Write File 2 VI to save an image with its overlay information to a file. You can read the information from the file into an image using the IMAQ Read Image and Vision Info VI.

Note  Use the IMAQ Set Overlay Properties VI to specify the behavior of overlay information when the image size or orientation changes. By default, calibration and overlay information is removed from an image when the image size or orientation changes.