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ridgrecpol

$ \bigcirc$Name


ridgrecpol Get the polar frequency grid used to perform ridgelet decomposition




$ \bigcirc$Command Synopsis


ridgrecpol [-I input_im] [-R output_re] [-C output_im] input_re



-I input_im : imaginary input of the 2D-FFT image

-R output_re : real output (2D-FFT image in polar grid)

-C output_im : imaginary output (2D-FFT image in polar grid)

input_re : real input of the 2D-FFT image




$ \bigcirc$Function Summary


void ridgrecpol (in_re , in_im , out_re , out_im )

Fimage in_re , in_im ;

Fimage out_re , out_im ;




$ \bigcirc$Description


Recall that ridgelet transform is obtained as a wavelet transform in the Radon domain. To get the Radon transform, a 2D FFT is computed and the rectangular 2D-Fourier plane is interpolated on a polar grid that is, along lines going through the origin in the frequency plane.

The module ridgrectpol precisely performs this interpolation, using a nearest-neighbor algorithm described in [SCD02].




$ \bigcirc$See Also


ridgelet.


$ \bigcirc$Version 1.0


Last Modification date : Thu Apr 15 08:03:52 2004


$ \bigcirc$Author


Guillaume Charpiat, Vincent Feuvrier






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