EntropyFilter

EntropyFilter[data,r]

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

EntropyFilter[data,{r1,r2,}]

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

Details

  • EntropyFilter returns the local randomness of a signal, commonly used to measure textures in an image. The size of the neighborhood is dependent on the value of r.
  • The function applied to each range-r neighborhood is Entropy.
  • 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, EntropyFilter operates separately on each channel.
  • EntropyFilter[data,{r1,r2,}] computes the entropy value in blocks centered on each sample.
  • MeanFilter assumes the index coordinate system for lists and images.
  • At the data boundaries, EntropyFilter uses smaller neighborhoods.

Examples

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Basic Examples  (3)

Apply an entropy filter to a vector of numbers:

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Filter a TimeSeries:

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Entropy filtering of random disks:

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Scope  (11)

Applications  (3)

Properties & Relations  (2)

Possible Issues  (1)

See Also

StandardDeviationFilter  CommonestFilter  ImageFilter  Entropy

Introduced in 2008
(7.0)
| Updated in 2012
(9.0)