1. A computer-implemented segmentation method for processing a gray-scale image made up of a plurality of pixels on a display, the image representing a plurality of nuclei, the method comprising: providing a set of instructions to a physical memory of the computer; configuring a processor of the computer by executing the set of instructions in the physical memory so as to automatically segment the image by: (a) setting at least one parameter in the segmentation algorithm, (b) thresholding the grey-scale image to create a black and white image; (c) post-processing to identify objects in the black and white image and to remove objects failing to meet predetermined criteria based on the black and white image and the gray-scale image; (d) segmenting to extract objects corresponding to the objects remaining after the post-processing step; (e) applying an edge detector on the segmented image to identify the edges of nuclei; (f) creating a mask for each nucleus to create a plurality of masks; (g) where masks overlap by a predetermined range of overlaps, splitting the overlapping masks to replace the overlapping masks in the plurality of masks, wherein the predetermined range of overlaps is from a lower bound to an upper bound of overlap area as a percentage of the combined area of the masks, the lower bound is in the range 1% to 10%, preferably 3% to 7%, and the upper bound is in the range 15% to 40%, preferably 20% to 30%; and (h) providing as an output a transformed image made up of mask regions representing the plurality of masks representing respective nuclei.