Re: reverse-engineering a color image diagram

Posted by Frederic V. Hessman on
URL: http://imagej.273.s1.nabble.com/WaitForUser-not-working-tp5009331p5009336.html

I’d like to take a color diagram with a given color bar showing the connection between displayed color and actual value and produce a final real (32 bit) image with the original values (well, as good as it gets).

I tried a quick-n-dirty PluginFilter which reads the RGB values off a ROI, lets me input the extremum orignal values represented by the bar, stores the results in R,G,B, and value arrays, and then tries to convert each color value (r,g,b) in the image to an estimated value v by minimizing the color distance

        (r-R[i])^2+(g-G[i])^2+(b-B[i])^2

but the result is less than spectacular.  Obviously, this sRGB Euclidean distance is not capturing the color nuances well enough.  Should probably use CIE L*a*b….

Surely there’s a plugin out there which does this….

Thanks!

Rick

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