Please see the discussion at http://forums.ni.com/t5/Machine-Vision/Test-for-Existence-of-Overlay-in-Image/m-p/1671398/highlight/....
Specifically, starting at message 7, I still need a way to find out if an individual overlay (eg. determine if overlay A is present when there might be three overlays A, B, C) can be determined to be present so I can just erase that one. There are workarounds involving more programming but for true image processing application, a function allowing testing for presence of individual overlay should be available in Vision. 25 years ago, I was doing this sort of thing using Grinnell image processors so again, surprised that this is currently not available.
Sincerely,
Don
Any idea that has received less than 7 kudos within 7 years after posting will be automatically declined.