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# EntropyFilter

 EntropyFilterfilters image by replacing every value by the information entropy of the values in its range r neighborhood. EntropyFilterapplies entropy filtering to an array of data.
• 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.
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:

Apply entropy filtering to show areas of higher information content with higher intensities:
 Out[1]=

Apply an entropy filter to a vector of numbers:
 Out[1]=
 Applications   (2)
Entropy filtering can reveal JPEG compression artifacts:
This reveals the presence of padding in an image:
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