I\'ve been banging my head against the wall for the better part of an hour trying to figure out what\'s going wrong here, and I\'m sure (or rather hoping) it\'s something fa
Saw the same problem after upgrading ImageMagick on a Linux box. There are some more notes here. I suspect some mismatch of ImageMagick libraries and linked ruby gems (which is in agreement with all the previous comments. Check out this similar thread at rubyforge. http://rubyforge.org/forum/forum.php?thread_id=48036&forum_id=33
My solution was to dump RMagick in favor of MojoMagick - a very lean ruby API which doesn't link to ImageMagick libraries but simply uses the console binaries.
It's available here : www.misuse.org/science/2008/01/30/mojomagick-ruby-image-library-for-imagemagick/
I've built a gem and added resize to fill with crop functionality which is available on github https://github.com/bunnymatic/mojo_magick