Re: help_standardizing images

Posted by Ryan Garrick on Apr 25, 2007; 2:59am
URL: http://imagej.273.s1.nabble.com/help-standardizing-images-tp3699688p3699689.html

Thanks for your help with this everyone.
 
Frederick, it looks like the procedure you suggested has worked quite
well. I haven't yet played around with equalization (or stretching, as
mentioned by Gabriel) that much, but might need to because although the
graycard in my reference image has a histogram of gray values with an
approx. normal distribution, the graycards in some of  target images give
a histogram with a slightly longer upper tail (c.f. a normal
distribution). If I use the min. and max. gray values alone to determine
scaling and offset, this tail is likely to have some impact on
standardization. Perhaps it would be reasonable to use the min. and modal
gray value of the histograms, the rationale being that it is more
important end up with comparable frequency distributions of gray values
rather than matching range limits?

cheers,
Ryan