Segmentation using morphology

Segmentation of locally darker somewhat circular regions using a morphology based method

This simple method can be used to segment locally darker regions in a grayscale image that have a somewhat circular appearance.
demo.m performs a segmentation on the example image recon_test.png.

The method has been used in medical imaging as part of an airway segmentation method to extract the 3D airways. See http://www.lungworkshop.org/2009/proc2009/297.pdf for details of the full method and http://image.diku.dk/exact/exact_team_result.php?team_id=15 for results.