3) EXIF
metadata should be preserved, even on resized images. Thumbnails can
be recreated, so junking those isn't an issue. But stripping unrecoverable
information, especially that which may contain author and license
information, is a problem when the images are borrowed and used downstream.
I wish I had a good way to strip just thumbnails, but I don't currently know
of one. Flickr has the same practice as well, and it's annoying....
This would require someone to rewrite the code. In understand that
mediawiki uses
http://en.wikipedia.org/wiki/ImageMagick to resize
images.
It does. Except for SVGs, which are rendered via rsvg.
There're two available parameters: -thumbnail and -resize. One strips
EXIF while the other doesn't.