Module imagingbook.spectral

Package imagingbook.spectral.dft

Interface Dft2d.Double

All Superinterfaces:

Dft2d

All Known Implementing Classes:

Dft2dDirect.Double, Dft2dFast.Double

Enclosing interface:

Dft2d

public static interface Dft2d.Double
extends Dft2d

Sub-interface for 2D DFT implementations operating on double data.

Nested Class Summary

Nested classes/interfaces inherited from interface imagingbook.spectral.dft.Dft2d

Dft2d.Double, Dft2d.Float

Method Summary

Modifier and Type	Method	Description
default void	checkSize(double[][] A)
default void	extractCol(double[][] g, int u, double[] col)
default void	extractRow(double[][] g, int v, double[] row)
default void	forward(double[][] gRe, double[][] gIm)	Performs an "in-place" forward DFT or FFT on the supplied 2D data.
Dft1d.Double	get1dDft(int size)	Returns a suitable 1D DFT of the specified size (double).
default double[][]	getMagnitude(double[][] re, double[][] im)	Calculates and returns the magnitude of the supplied complex-valued 2D data.
default void	insertCol(double[][] g, int u, double[] col)
default void	insertRow(double[][] g, int v, double[] row)
default void	inverse(double[][] GRe, double[][] GIm)	Performs an "in-place" inverse DFT or FFT on the supplied 2D spectrum.
default void	transform(double[][] gRe, double[][] gIm, boolean forward)	Transforms the given 2D arrays 'in-place'.

Methods inherited from interface imagingbook.spectral.dft.Dft2d

getHeight, getScalingMode, getWidth

Method Details

get1dDft

Dft1d.Double get1dDft(int size)

Returns a suitable 1D DFT of the specified size (double).

Parameters:

size - the size of the DFT

Returns:

a Dft1d.Double instance

transform

default void transform(double[][] gRe,
 double[][] gIm,
 boolean forward)

Transforms the given 2D arrays 'in-place'. Separate arrays of identical size must be supplied for the real and imaginary parts of the signal (forward) or spectrum (inverse), neither of which may be null.

Parameters:

gRe - real part of the input signal or spectrum (modified)

gIm - imaginary part of the input signal or spectrum (modified)

forward - forward transformation if true, inverse transformation if false

extractRow

default void extractRow(double[][] g,
 int v,
 double[] row)

insertRow

default void insertRow(double[][] g,
 int v,
 double[] row)

extractCol

default void extractCol(double[][] g,
 int u,
 double[] col)

insertCol

default void insertCol(double[][] g,
 int u,
 double[] col)

forward

default void forward(double[][] gRe,
 double[][] gIm)

Performs an "in-place" forward DFT or FFT on the supplied 2D data. The input signal is replaced by the associated DFT spectrum.

Parameters:

gRe - real part of the signal (modified)

gIm - imaginary part of the signal (modified)

See Also:

• transform(double[][], double[][], boolean)

inverse

default void inverse(double[][] GRe,
 double[][] GIm)

Performs an "in-place" inverse DFT or FFT on the supplied 2D spectrum. The input spectrum is replaced by the associated signal.

Parameters:

GRe - real part of the spectrum (modified)

GIm - imaginary part of the spectrum (modified)

See Also:

• transform(double[][], double[][], boolean)

getMagnitude

default double[][] getMagnitude(double[][] re,
 double[][] im)

Calculates and returns the magnitude of the supplied complex-valued 2D data.

Parameters:

re - the real part of the data

im - the imaginary part of the data

Returns:

a 2D array of magnitude values

checkSize

default void checkSize(double[][] A)