"reverse" segment cropper

I was wondering if it is possible to have some sort of reverse segment cropper. So as to delete the segment from my main image, so as counting particles is not disturbed by my segment in the future, as the segment usually also gets counted. Or would it be easier, and faster in calculation, to filter out the segment from the particle analysis table later on?

Both is possible. Did you take a look at the "GroupBy" or "Labeling Filter" Node Tutorials on the example server? These examples might help you a lot.