org.openimaj.image.processing.algorithm

Class FourierTransformComplex

java.lang.Object

org.openimaj.image.processing.algorithm.FourierTransformComplex

public class FourierTransformComplex
extends Object

Perform forward and inverse Fast Fourier Transforms on image data. This class computes the result of the transform in complex form. If you want the result in polar form (in terms of phase and magnitude) then use the FourierTransform instead.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Constructor Summary

Constructors

Constructor and Description
FourierTransformComplex(FImage image, boolean centre) Construct Fourier Transform by performing a forward transform on the given image.
FourierTransformComplex(FImage real, FImage imaginary, boolean centre) Construct Fourier Transform object from the given magnitude and phase images in the frequency domain.

Method Summary

Modifier and Type	Method and Description
FImage	getImaginary()
FImage	getReal()
FImage	inverse() Perform the inverse FFT using the underlying magnitude and phase images.
boolean	isCentre()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FourierTransformComplex

public FourierTransformComplex(FImage image,
                               boolean centre)

Construct Fourier Transform by performing a forward transform on the given image. If the centre option is set, the FFT will be re-ordered so that the DC component is in the centre.

Parameters:

image - the image to transform

centre - should the FFT be reordered so the centre is DC component

FourierTransformComplex

public FourierTransformComplex(FImage real,
                               FImage imaginary,
                               boolean centre)

Construct Fourier Transform object from the given magnitude and phase images in the frequency domain. The resultant object can then be used to construct the image using the inverse() method.

Parameters:

real - the real image

imaginary - the imaginary image

centre - is the DC component in the image centre?

Method Detail

inverse

public FImage inverse()

Perform the inverse FFT using the underlying magnitude and phase images. The resultant reconstructed image may need normalisation.

Returns:

the reconstructed image

getReal

public FImage getReal()

Returns:

the real image

getImaginary

public FImage getImaginary()

Returns:

the imaginary image

isCentre

public boolean isCentre()

Returns:

true if the DC component is in the centre; false otherwise