ImageMagick 6.8.9-9 fixes an unspecified bug in image resize code. It's likely [1] that this is pretty low-impact issue. [1]: https://bugs.gentoo.org/show_bug.cgi?id=527028#c0
Created ImageMagick tracking bugs for this issue: Affects: fedora-all [bug 1158520]
ImageMagick-6.8.8.10-9.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.