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based on an earlier version of the Wolfram Language.
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BottomHatTransform

BottomHatTransform[image, ker]
gives the morphological bottom-hat transform of image with respect to structuring element ker.
BottomHatTransform[image, r]
gives the bottom-hat transform with respect to a range r square.
  • The structuring element ker is a matrix containing 0s and 1s.
  • If multiple image channels are present, BottomHatTransform operates on each of them separately.
  • BottomHatTransform preserves regions smaller than the structuring element whose channel values are smaller than their surroundings.
Bottom-hat transform applied to a color photo:
Extract small dark regions from a color image:
Use a disk-shaped structuring element to extract washers that are smaller than the specified size:
The bottom-hat transform effectively inverts high-frequency regions:
Bottom-hat transform applied to a color photo:
In[1]:=
Click for copyable input
Out[1]=
 
Extract small dark regions from a color image:
In[1]:=
Click for copyable input
Out[1]=
 
Use a disk-shaped structuring element to extract washers that are smaller than the specified size:
In[1]:=
Click for copyable input
Out[1]=
 
The bottom-hat transform effectively inverts high-frequency regions:
In[1]:=
Click for copyable input
In[2]:=
Click for copyable input
Extract thin dark features:
Add the result to the original image to remove those thin features:
New in 7