Excluding regions from greyscale profiles

Posted by Fitzgabbro on Mar 09, 2011; 4:32pm
URL: http://imagej.273.s1.nabble.com/Excluding-regions-from-greyscale-profiles-tp3685461.html

I am trying to draw profiles along lines of 5-10 pixel width across crystals, but these crystals have cracks.  Where these cracks intersect the line, I would like imagej to ignore them, and average only over the width of the line that is not over the crack.  Is there a way of drawing round the cracks (and other defects), and to then exclude those regions from the profiles I draw?  The functions to do this with ROIs don't seem to work for lines.

Thanks,
Gareth