bundles / skimage latest / skimage / morphology / gray / _patch_footprint_mirroring
function
skimage.morphology.gray:_patch_footprint_mirroring
source: /dev/scikit-image/src/skimage/morphology/gray.py :100
Signature
def _patch_footprint_mirroring ( footprint ) Summary
Mirror asymmetric footprints before dispatching to skimage2.
Extended Summary
This function ensures backwards compatibility when asymmetric footprints are passed to skimage.morphology.dilation, skimage.morphology.closing and skimage.morphology.black_tophat. See _Notes_ for details.
Parameters
footprint: ndarray or tuple, optional
Returns
patched_footprint: ndarray or tuple
Notes
Inside scipy.ndimage.grey_dilation the footprint is inverted/mirrored. This inversion is intentional so that closing and opening (the compositions of erosion and dilation) are extensive and anti-extensive.
skimage.morphology.dilation accidentally undoes this by mirroring
the footprint, before passing it to scipy.ndimage.grey_dilation.
skimage.morphology.closing and skimage.morphology.black_tophat then mirror/invert again to correct for this.
In skimage2 we drop all mirroring and align with SciPy. This function documents this procedure and ensures the wrappers around skimage2 keep the old behavior for skimage.morphology.dilation, skimage.morphology.closing and skimage.morphology.black_tophat.
skimage.morphology.erosion, skimage.morphology.opening and skimage.morphology.white_tophat _aren't_ affected.
Aliases
-
skimage.morphology.gray._patch_footprint_mirroring