Cellular outlining from cytokeratin. A large epithelial cell cluster is surrounded by several smaller clusters and individual cells. The image of raw cytokeratin fluorescence, from positively stained epithelial cells (a), is used as an input for the software outlining algorithm. Outline results are drawn in pink around recognized cells and clusters and are subsequently measured for size and location (b). The Hoechst fluorescent image is used to aid in discriminating real cells from debris (c).