Segmentation of time-lapse Nanolive images

I’m trying to segment the cells in this movie (there are 2 “main characters” and 2 "side characters) so that they’re false-colored different colors and easily movie. I acquired this using a Nanolive microscope (a form of holographic imaging https://nanolive.ch/technology/nanolive-imaging/).

In the tiff I’ve attached it’s just 1 frame (of 961 in this particular acquisition) frame466.tif (1.0 MB) where you can see two cells. Here’s a link to an avi of the full movie and here’s a link to tiff stack of the same acquisition.

Any tips for how to go about segmenting these two cells from each other? Ideally a process that wouldn’t be too tedious for applying this method to track the cells through time.

I tried out PHANTAST without any success…I’m just not very familiar with segmenting non-fluorescent images.

Thanks in advance for your help!