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fft2dpol

$ \bigcirc$Name


fft2dpol Polar 2D FFT




$ \bigcirc$Command Synopsis


fft2dpol [-i] [-I input_im] [-M output_rho] [-P output_theta] input_re



-i : to compute inverse FFT

-I input_im : imaginary input (Fimage)

-M output_rho : modulus output (Fimage)

-P output_theta : phase output (Fimage) in [-M_PI,M_PI]

input_re : real input (Fimage)




$ \bigcirc$Function Summary


void fft2dpol (in_re , in_im , out_rho , out_theta , i_flag )

Fimage in_re , in_im , out_rho , out_theta ;

char *i_flag ;




$ \bigcirc$Description


Like the fft2d module, this one computes the Fast Fourier Transform of a 2D input, given by two Fimages (real and imaginary parts). However, it returns the Fourier Transform in polar coordinates, meaning the modulus and the phase (in [- $ \pi$,$ \pi$]) as Fimages.

Since FFT only applies to images which dimensions are power of 2, the input will be shrinked to proper dimensions if necessary using the fshrink2 module. In this case a warning message will be produced.

Several special cases can occur when you use this module as a C subroutine :




$ \bigcirc$See Also


fft2d.

fft2drad, fft2dview.


$ \bigcirc$Version 1.2


Last Modification date : Thu Nov 29 20:23:56 2001


$ \bigcirc$Author


Lionel Moisan






next up previous contents index
Next: fft2drad Up: Reference Previous: fft2d   Contents   Index
mw 2004-05-05