BUG: pad images to avoid rotation issue with cropped images
BUG: pad images to avoid rotation issue with cropped images

Former-commit-id: 2110358e83bfd3554403480ea026fa92698fa92f
Former-commit-id: ffcb1ba81456f75b6ee91640fb92aa1b9e59462d
3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox,3324fr/spinalcordtoolbox