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EntropyFilter

EntropyFilter
filters image by replacing every value by the information entropy of the values in its range r neighborhood.
EntropyFilter
applies entropy filtering to an array of data.
MORE INFORMATION
  • EntropyFilter computes the information entropy of the values in blocks centered on each pixel.
  • Given a set of values , the information entropy is taken to be .
  • For multichannel images, EntropyFilter computes the local entropy of the set of pixel vectors.
  • At the edges of an image, EntropyFilter uses smaller neighborhoods.
  • EntropyFilter uses neighborhoods with vertical range and horizontal range .
  • In EntropyFilter, data can be an array of any rank, and can contain symbolic as well as numerical entries.
EXAMPLESCLOSE ALL
Basic Examples   (3)
Entropy filtering of random disks:
Apply entropy filtering to show areas of higher information content with higher intensities:
Apply an entropy filter to a vector of numbers:
Entropy filtering of random disks:
In[1]:=
Click for copyable input
In[2]:=
Click for copyable input
 
Apply entropy filtering to show areas of higher information content with higher intensities:
In[1]:=
Click for copyable input
Out[1]=
 
Apply an entropy filter to a vector of numbers:
In[1]:=
Click for copyable input
Out[1]=
Applications   (2)
Entropy filtering can reveal JPEG compression artifacts:
This reveals the presence of padding in an image:
New in 7
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