optimizing an animated gif

[anthony]

this is just a warning that some of the optimized frames are actually 'empty' that is they don't do anything and could be deleted.
It come from the internal use of the crop function
http://imagemagick.org/Usage/crop/#crop_missed

Add -quite to tell IM that the warnings are OK, you don't need to know.
See IM Examples Animation optimization.
http://imagemagick.org/Usage/anim_basic ... ose_images

If you want even more optimization use -layers RemoveDups
See http://imagemagick.org/Usage/anim_opt/#removedups
before the -layers optimize