Functions | |
| cpl_image * | omega_gen_lowpass (int xs, int ys, double sigma_x, double sigma_y) |
| Generate a low pass filter for FFT convolution . | |
| cpl_image * | omega_get_spatial_freq (cpl_image *flat, cpl_mask *bpm, double gausfilt, int mirrorx, int mirrory) |
| Get low spatial frequency componenets from the flat field using the FFTW. | |
| cpl_image * | omega_mirror_edges (cpl_image *image, int dx, int dy) |
| expand image by mirroring edges | |
This module provides functions to do fast fourier transformations
#include "omega_bpm.h" #include "omega_utils.h"
| cpl_image* omega_gen_lowpass | ( | int | xs, | |
| int | ys, | |||
| double | sigma_x, | |||
| double | sigma_y | |||
| ) |
Generate a low pass filter for FFT convolution .
| xs | x size of the generated image. | |
| ys | y size of the generated image. | |
| sigma_x | Sigma for the gaussian distribution. | |
| sigma_y | Sigma for the gaussian distribution. |
This function generates an image of a 2d gaussian, modified in such a way that the different quadrants have a quadrants of the gaussian in the corner. This image is suitable for FFT convolution. Copied from eclipse, src/iproc/generate.c
The returned image must be deallocated.
Definition at line 84 of file omega_fftw.c.
Referenced by omega_get_spatial_freq().
| cpl_image* omega_get_spatial_freq | ( | cpl_image * | flat, | |
| cpl_mask * | bpm, | |||
| double | gausfilt, | |||
| int | mirrorx, | |||
| int | mirrory | |||
| ) |
Get low spatial frequency componenets from the flat field using the FFTW.
Function to calculate the low spatial frequency
| flat | twilight or dome flat | |
| bpm | optonal bad pixels image | |
| gausfilt | Gaussian Fourier filter size | |
| mirrorx | for mirroring edges (ocfft continuity) | |
| mirrory | for mirroring edges (ocfft continuity) | |
| medfilt | for cleaning bad pixels |
Definition at line 171 of file omega_fftw.c.
References omega_gen_lowpass(), and omega_mirror_edges().
Referenced by omega_make_mflat().
| cpl_image * omega_mirror_edges | ( | cpl_image * | image, | |
| int | dx, | |||
| int | dy | |||
| ) |
expand image by mirroring edges
| image_in | Image. | |
| x_size | the number of pixels in x to expand | |
| y_size | the number of pixels in y to expand |
Definition at line 266 of file omega_fftw.c.
Referenced by omega_get_spatial_freq().
1.6.1