ImagePeriodogram

ImagePeriodogram[image]
shows the squared magnitude of the discrete Fourier transform (power spectrum) of image.

ImagePeriodogram[image, n]
shows the average of power spectra of nonoverlapping partitions of size n×n.

ImagePeriodogram[image, n, d]
uses partitions with offset d.

ImagePeriodogram[image, n, d, wfun]
applies a smoothing window wfun to each partition.

ImagePeriodogram[image, n, d, wfun, m]
pads partitions with zeros to length m prior to the computation of the transform.

Details and OptionsDetails and Options

  • ImagePeriodogram logarithmically scales the power spectrum of the image and adjusts the values so that they range from to .
  • In ImagePeriodogram[image, n, d, wfun], the smoothing window wfun can be specified using a window function that will be sampled between and , or a list of length n. The default window is DirichletWindow, which effectively does no smoothing.
  • ImagePeriodogram[image, n] is equivalent to ImagePeriodogram[image, n, n, DirichletWindow, n].
  • ImagePeriodogram[image, {n1, n2}] partitions image into blocks of size ×.
  • For 3D images, ImagePeriodogram[image, {n1, n2, n3}] partitions image into blocks of size ××.
  • For multichannel images, ImagePeriodogram returns a multichannel image where each channel is the power spectrum computed for each channel separately.
  • ImagePeriodogram accepts the Alignment option that determines the location of the zero frequency term. The default is Alignment->Center. With Alignment->{Left, Top}, the zero frequency term is placed at the top-left corner of the image.

ExamplesExamplesopen allclose all

Basic Examples (3)Basic Examples (3)

Power spectrum of an image of a disk:

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Power spectrum of a color image:

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Power spectrum of a 3D image of the hydrogen wave function:

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