On Wed, Mar 28, 2001 at 01:12:28PM +0200, Sven Neumann wrote: > Hi, > > Zachary Beane <xach@xxxxxxxx> writes: > > > > - Biased color reduction > > > > > > This is a feature I saw in photoshop. When reducing the colors of an > > > image, it will try to preserve colors within the active selection > > > more than it tries to preserve those outside of it. For example, if > > > you want to keep skin tones in an image, but want to otherwise > > > reduce the overall number of colors, you would select a few > > > representative areas of skin before doing the reduction. > > > Personally, I can't count the number of times I've converted an image > > to Indexed only to find the black had gone suddenly slightly > > off-black, or another solid color that I really needed at a particular > > value had suddenly shifted slightly. I'd love to be able to select > > those colors before conversion to hint to the Indexed conversion, > > "these exact values are important to me." > > Talked to Adam about that issue on #gimp lately and he seems to be > biased towards changing the conversion-algorithm to be intelligent > enough to do the right thing without user interaction. According > to the latest ChangeLog entries, he seems to be actually working on > this. His ChangeLog entries are what renewed my interest in this. But I'm curious; how can the conversion algorithm know what the right thing is? If I'm going from many colors (one of which is a particular shade of mauve that matches my web page) to, say, 11 colors, how can it know that my mauve is one of the colors to preserve unmodified? Zach -- xach@xxxxxxxx Zachary Beane http://www.xach.com/
