Converting https://upload.wikimedia.org/wikipedia/commons/archive/5/59/20140414211458%21Stara_Ljubljana_-_Ciril_Metodov_trg.tiff on my machine via imagemagick works correctly. Some sort of bug in the converter used on the production servers?
The only relevant difference between the current working and the old broken image seems to be the lack of compression. (The old version has transparency and the new does not, but that does not seem to be the issue here.)
In https://commons.wikimedia.org/w/index.php?title=Commons:Village_pump&oldid=121392867#Change_of_colours_after_a_move Ruslik wrote "It is probably related to the fact that this tiff file uses jpeg compression."
(In reply to Tisza Gergő from comment #1)
20140414211458%21Stara_Ljubljana_-_Ciril_Metodov_trg.tiff on my machine via
imagemagick works correctly. Some sort of bug in the converter used on the
Also fine for me too. All signs point to bug in specific version of image magick used on WMF servers
Here an other example of a whole book uploaded by a GLAM in Switzerland, suffering of an ugly "pink effect":
If the solution is to install a recent version of Imagemagick, we should maybe think about it and assign the bug to ops?
WMF is upgrading the operating system on the servers as part of their migration to HHVM. They are upgrading from Ubuntu 12.04 ("precise") to 14.04 ("trusty"), which includes a new version of ImageMagick (see packages.ubuntu.com).
(and imagemagick is not listed in the list of tools to be updated in the ticket description).
That list only includes Ubuntu packages that WMF had had to rebuild for precise. It does not include packages that came directly from Canonical without changes.