How to quantify the contrast of particular features in an image?
Posted by Josh Doe-2 on Dec 27, 2006; 9:02pm
URL: http://imagej.273.s1.nabble.com/How-to-quantify-the-contrast-of-particular-features-in-an-image-tp3700729.html
This is somewhat off-topic; if any of you can recommend a good image
analysis mailing list or forum, I would appreciate it, so I can ask these
types of questions there.
I'm writing a plugin for ImageJ that is supposed to give some sort of
contrast number which quantifies how easy or difficult it is to pick out
individual features in an image. The user makes a selection, and I then take
that ROI and the image and produce this number. I have two questions:
1) What metric should I use for this number? What I've found so far are the
difference of the feature and background mean pixel values, and then adding
in the feature variance in quadrature. These don't really satisfy me though.
I feel there should be some higher order statistics involved in this, but I
don't have a good background in image analysis. I've searched Google scholar
and read some papers, but haven't really found anything like I need.
2) What do I consider the background? So far I've been using the Euclidiean
distance map (EDM) plugin, and then using the Wand to choose my background
so it has roughly the same number of pixels as the feature has. This creates
an annulus or band around the feature, much like the "Make Band" command
does. Or maybe I should use the entire image for my background.
If anyone has any pointers, or can tell me where to look, I'd really
appreciate it!
Josh D