Re: [Gimp-user] Is there a single bit that can accidentally flip an image to negative? (not Gimp specific)

[Elle Stone <l elle stone gmail com>]

It turns out that the embedded profile in "wrong.jpg" does have an
incorrect tone response curve. See the attached screenshot comparing
the incorrect TRC to what it should look like. The embedded profile
compresses the original sRGB 1024-point TRC range from 0 to 65535 down
to about half the original range, then drops abrubtly to 0. Very odd.
Never seen that before.

So is there some software in your toolchain of softwares that handles
your images, that is somehow embedding a corrupt version of the
original sRGB ICC profile? Is there a timestamp that might let you
know when the "inverted" images were last handled, which might let you
know what software embedded the corrupt profile?

Elle Stone
-- 
http://ninedegreesbelow.com - articles on open source digital photography