= Morphological dilation
{title2=$A\oplus B$}
For foreground <set> $A$ and <structuring element> $B$, <morphological dilation> is their <Minkowski sum>:
$$
A\oplus B=\{a+b:a\in A,\ b\in B\}.
$$
Equivalently, place a translated copy of $B$ at each foreground position and take their <union>. For $A=\{0,2\}$ and $B=\{0,1\}$, the result is $\{0,1,2,3\}$, connecting the separated input points.
In <image processing>, <morphological dilation> can enlarge bright regions or bridge small gaps. The grayscale version for a flat footprint takes a local maximum, with the footprint reflected according to the stated offset convention.<Morphological Filtering in the scikit-image documentation>[Dilation, local maximum and thickening example]{ref} Asymmetric footprints make reflection conventions visible; symmetric disks hide that distinction. <Morphological dilation> alone generally enlarges a region, whereas <morphological opening> combines it with <morphological erosion>.
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