>On Thursday 05 March 2009, James wrote:
>> Ideally, I'd like all the yellowed paper that forms the background
>> of these images to turn as close to white as possible, while all the
>> text should be as close to black as possible. Can anyone point me to
>> I can try under gimp that will help me accomplish these aims?
>If you have to work with many pages, my first idea would be to do an
>white balance correction (Colors > Auto > White Balance). With a little
>luck, it'll pick the "yellow" as white and the pencil as black. If that
>doesn't work out as you expect, do it manually with the levels tool, and
>make use of the three eye droppers (mainly the white one) in the "All
>Getting to know the levels tool (or curves too for even more control) will
>help you with photos and scans anyway.
Thanks for those tips, Daniel. Some preliminary experimentation with white
balance correction gave slightly better results than I've gotten in my own
unguided attempts with the program. I'll look more into the levels tool now
and see whether that might give better results yet.
As further information on my project, I mention yellowing of the paper. It
would probably be more accurate to call it "browning" since, in some
instances, its shade can approach the same intensity of light pencil markings.
Also, since I photographed this text under highly unprofessional
circumstances, some pages have a little glare and/or a little shadow on them.
So this complicates things a bit more for my purposes (the purpose being to
end up with something as close as possible to black text on a white
Now, off to sudy up a bit on the levels tool.
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