[OT] Gimp: color to alpha?

[Luca Manganelli]

Hi, I want to substitute a color to alpha.

The problem is that the Filter -> Colors -> Color to Alpha is not
"precise": I want tho change ONLY one color, not a range.

How can I do it?

--
"An algorithm must be seen to be believed."
   -- Donald Knuth, in "Fundamental Algorithms"
                               http://www.trapanator.com/blog