BUG: fixed issue with nibble and float16
BUG: fixed issue with nibble and float16

Former-commit-id: aa482ddd951fb66f39899abe9dd8cda8744bc013
Former-commit-id: 6c8bd8dcf458eaef387818cdf5dad3c526304560
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox