Bug#774266: gdk-pixbuf seems to be the culprit

[Michael Below]

I discussed the issue with libjpeg-turbo upstream and eog upstream.
libjpeg (-turbo or not) doesn't offer a CMYK-RGB conversion. eog uses
gdk-pixbuf for image decoding, and gdk-pixbuf contains a simplified
CMYK-RGB conversion.

https://bugzilla.gnome.org/show_bug.cgi?id=737440#c9
http://sourceforge.net/p/libjpeg-turbo/mailman/message/33266986/

This simplified conversion is a bad idea. gdk-pixbuf should do a
correct color managed conversion, or no conversion at all. Having CMYK
images show up with red-faced people etc. is more confusing than
helpful.