Drawing a circle around a point


Currently, I have the center points of the blobs which may be circular/non-circular. I want to create a circle of defined radius around the center of the blob. I would like the process to be automatic so that the overlay circle around the center is added as an ROI into the ROI Manager.


The drawOval macro function should have everything you need (after doing a little bit of math to get the x and y start coordinates from your center and radius).


I got the circle on the image. But it is not able to add to the ROI Manager as an ROI. Gives a prompt: “Active image doesn’t have a selection”


I think the function that you have to use is makeOval instead of drawOval


Just for the record:
If your question is related to the problem mentioned in your other thread
then you should be aware that drawing a reference circle (circular selection) is not required. All you need is the transformation center.




Yeah, makeOval is the function instead of drawOval.

Many Thanks,


Yes, sorry, I confused the two functions. Thanks for rectifying!