Fig. 1.

Ambiguous segmentation scenario. Left: original image, middle: noisy image, right: class conditional distributions. Distributions clearly overlap which should result in a segmentation ambiguity for the upper part of the circle which was deliberately chosen to have intensities in between the background and the foreground (bottom part of the circle). Background class conditional distribution displayed as a solid black line, foreground class conditional distribution displayed as a dash-dotted black line