Tracking fluorescent cells with coupled geometric active contours

This paper presents a method based on geometric active contours to segment and track biological cells in fluorescence videomicroscopy. To achieve robust segmentation of fluorescent cells with fuzzy boundaries, we use the region-based model introduced by Chan and Vese. The level set approach allows fully automatic initialization, detection of dividing cells and of cells entering the field of view during the sequence. However, the standard approach using only one level set function leads to undesired merging of touching cells and failure of tracking. To prevent this, we represent each cell by its own level set function and introduce a coupling constraint that minimizes overlaps of active contours. This technique maintains the separation of contours and allows tracking to proceed even when the boundary between cells is weak or invisible.