Image segmentation is imperfect. (a) Representative composite image from the training image set. Bounding boxes determined from cell-body stain are indicated for segmented objects that were classed by human review as either poorly segmented (red boxes) or well segmented (blue boxes). Letters (b-e) indicate individual segmented objects. Nuclear stain (DAPI) is blue; Cell body (CMFDA) is green; Actin is red. (b-c) Magnified images of well-segmented objects containing a complete nucleus and cytoplasmic region. Green outlines indicate segmented nuclei; blue outlines delimit the segmented cell body. (d-e) Magnified images of poorly-segmented objects containing partial cell bodies and nuclei.