This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# MaxFilter

 MaxFilterfilters image by replacing every value by the maximum in its range r neighborhood. MaxFilterapplies max filtering to an array of data.
• MaxFilter finds the maximum in × blocks centered on each pixel.
• At the edges of an image, MaxFilter uses smaller neighborhoods.
• MaxFilter uses neighborhoods with vertical range and horizontal range .
• For multichannel images, MaxFilter replaces each pixel by a pixel in its neighborhood that has the maximum total intensity, averaged over all channels.
• In MaxFilter, data can be an array of any rank.
Use a maximum filter to dilate the brighter parts of a color image:
Dilate the brighter parts of an image to remove thin, dark features:
Maximum filter of a vector:
Use a maximum filter to dilate the brighter parts of a color image:
 Out[1]=

Dilate the brighter parts of an image to remove thin, dark features:
 Out[1]=

Maximum filter of a vector:
 Out[1]=
 Applications   (1)
Remove pepper noise from an astronomical image:
Subsequent application of MaxFilter and MinFilter is the same as Closing:
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