MASK LABEL

        [ADVANCED\]MASK LABEL

      Convert the Mask to labelled connex regions. Pixel in each region is given
    a common integer value, the region number. Region numbers are ordered by de-
    creasing number of pixels.

    *** Caution: currently only works on 2-D masks. ***

    For  3-D  masks, the first plane is the result of collapsing the 3-D mask on
    it, and then applying the labelling process. This may  change  according  to
    further needs.