This step seems  certainly the easiest but will be in fact quite complex since we are working with stacks and several dozens of microalgaes have been segmented.
We want to extract concentric intensity from each microalgae. As we can operate only one list of region of interest, we have to be careful with the indexes of the new ROIS that will be created.  In addition to that, instead of having as many table as microalgae, we will create a finaltable in which each line will correspond to a single microalgae.

1. Initialization