MaxFilter

MaxFilter[data,r]

filters data by replacing every value by the maximum value in its range-r neighborhood.

MaxFilter[data,{r1,r2,}]

uses ri for filtering the ^(th)dimension in data.

Details

  • MaxFilter is a nonlinear filter commonly used to locally smooth data and diminish pepper-like noise, where the amount of smoothing is dependent on the value of r.
  • The function applied to each range-r neighborhood is Max.
  • The data can be any of the following:
  • listarbitrary-rank numerical array
    tseriestemporal data such as TimeSeries, TemporalData,
    imagearbitrary Image or Image3D object
    audioan Audio object
  • For multichannel images and audio signals, MaxFilter operates separately on each channel.
  • MaxFilter[data,{r1,r2,}] computes the maximum value in blocks centered on each sample.
  • MaxFilter assumes the index coordinate system for lists and images.
  • At the data boundaries, MaxFilter uses smaller neighborhoods.

Examples

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Basic Examples  (3)

Maximum filter of a list:

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Filter a TimeSeries:

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Maximum filtering of a color image:

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Scope  (12)

Applications  (4)

Properties & Relations  (3)

See Also

Max  MinFilter  MeanFilter  RangeFilter  MedianFilter  Dilation  ImageFilter

Introduced in 2008
(7.0)
| Updated in 2015
(10.2)