Bigger points with Imaq overlay points

[Guus]

Hello everyone,

I'm using Imaq overlay points but the points are barely visible. Is there any way to make the litter red points  bigger?

Best regards,

Guus

[TiTou]

I think you can use the "oval overlay", you just have to calculate the rectangle in which the oval has to fit ; just center le rectangle on the point coordinates.

Hope this helps 😉

[halvorka]

I've run into the same problem.  Is this really the simplest solution?  If I have an arbitrarily long array of points I would have to auto-index into a for loop and calculate the bounding box for each one and then use the overlay oval function?  It seems silly that NI wouldn't have included some options in the "overlay points" function to avoid this problem.  Overlay points is attractive because it can take multiple points at once (unlike all the other overlay functions, which would need to be implemented inside a loop), and it would have been nice to represent the points with various symbols or a bitmap.  I'm displaying the points on a live video feed, so I'm concerned about adding unnecessary overhead.  If overlay oval really is the way to do it, then I'll probably just continue to strain my eyes to see the little dots.

In my case, I have a single ROI with multiple rectangular contours for tracking particles.  I like to see the bounding rectangles and their centers on the image.  Currently, I use overlay ROI to take care of the rectangles, and overlay points to show the center positions.

[nesslersreagent]

I had recently encountered the same problem, of the points produced by the IMAQ Overlay Points VI being too small.

The attached subVI solves the problem.

Inputs:

(1) X (1d Array): Holds the x co-ordinates of the points.

(2) Y (1d Array): Holds the y co-ordinates of the points.

(3) Size: Radius of point in pixels

Nothing fancy here. Just a basic loop with the IMAQ Overlay Oval VI, as mentioned in the previous posts.

Cheers.