ImageMagick 6.8.9-9 fixes an unspecified bug in image resize code.
It's likely  that this is pretty low-impact issue.
Created ImageMagick tracking bugs for this issue:
Affects: fedora-all [bug 1158520]
ImageMagick-188.8.131.52-9.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.