BUG: process_segmentation: fixed issue #395
BUG: process_segmentation: fixed issue #395

Former-commit-id: aa616faf6e6a0d69e5869b4ef2d0c589735135f5
Former-commit-id: c646c177455aaa8b80e23ff233720d213b572477
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox