Fig. 4

An example of the segmentation procedure through all three steps. a Laboratory image. The candidate spheroids are marked by circles. The yellow circle shows a lost spheroid in the first step of traditional image processing. b The traditional image processing output. c The shallow CNN result. (In comparison to the first step, one more spheroid is detected.) d The final mask by deeper CNN (in comparison to the second step, the modification on the spheroid edges is seen in some cases)