Successful use of rmagick also requires that you explicitly call the ".destroy!" method on all images(including intermediary ones) to ensure that memory is freed up. Looking at Ruby's Object space shows that this method successfully marks the images for deletion. This eliminated the memory leaks for me. You may have to also call GC.start after ".destroy!" if you want the objects cleaned up as quickly as possible.

See: http://rubyforge.org/forum/forum.php?thread_id=1374&foru...