pifft

Performs inverse Fast Fourier Transform.

Synopsis

pifft [-m mask] [im_in1|-] [im_in2|-] [im_out1|-] [im_out2|-]

Description

ipfft computes the inverse Fast Fourier Transform of the input complex image im_in1. The input complex image is composed of two images:

im_out1 is the real part of the transform;
im_out2 is the imaginary part of the transform.

The output complex image is composed of two images:

im_in1 is the real part;
im_in2 is the imaginary part.

Fast Fourier Transform is a way of going from the frequency domain to the spatial domain.

Inputs

im_in1: a gray level image (the real part of the transform).
im_in2: a gray level image with the same properties than im_in1 (the imaginary part of the transform).

Outputs

im_out1: a gray level image (the real part of the transform).
im_out2: a gray level image (the imaginary part of the transform).

Result

Returns SUCCESS or FAILURE.

Examples

Converts an image of a square from the spatial domain to the frequency domain and reciprocally:

   pshapedesign 256 256 0 2 20 0 square.pan
   pshapedesign 256 256 0 0  0 0 empty.pan
   pfft square.pan empty.pan real.pan imaginary.pan
   pmodulus real.pan imaginary.pan modulus.pan
   pphase real.pan imaginary.pan phase.pan
   pifft real.pan imaginary.pan square1.pan empty1.pan
   plineartransform 0 0 255 square1.pan square2.pan
   pim2uc square2.pan newsquare.pan

C++ prototype

Errc IFFT( const Img2duc &im_in1, const Img2duc &im_in2, Img2dsf &im_out1, Img2dsf &im_out2 );

Version française

Transformée de Fourier Rapide Inverse d'une image.

Authors: Herissay & Berthet