ridgrecpol Get the polar frequency grid used to perform ridgelet decomposition
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
void ridgrecpol (in_re , in_im , out_re , out_im )
Fimage in_re , in_im ;
Fimage out_re , out_im ;
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].
Last Modification date : Thu Apr 15 08:03:52 2004
Guillaume Charpiat, Vincent Feuvrier