| colored_noise.q | |
| Functions | |
| soft_step | A soft step function at x=1 (based on the cosine function) |
| psd_noise1f | Computes a 2D power spectral density for 1/f noise (vertical line noise) |
| psd_noise1f2 | Computes a 2D power spectral density for radial 1/f noise |
| psd_ct_ramp_spectrum_noise | Computes a 2D power spectral density for noise in CT images caused by the filtered back projection algorithm (with ramp filtering) |
| psd_ct_hann_filter_noise | Computes a 2D power spectral density for noise in CT images caused by the filtered back projection algorithm (with Hann smoothing filter) |
| psd_mri_elliptical_filter_noise | Computes a 2D power spectral density for noise in MRI images with the elliptical filter |
| psd_partial_kspace_noise | Computes a 2D power spectral density for noise in MRI images caused by partial kspace acquisition |
| psd_ef_partial_kspace_noise | Computes a 2D power spectral density for noise in MRI images caused by combined effects of the elliptical filter and partial kspace acquisition |
| psd_paltv_noise | Computes a simple (example) model for noise in PAL TV |
| psd_glb_noise | Computes the power spectral density for Gaussian Lumpy backgrounds (mainly intended for medical image quality assessment, used in channelized Hotelling observer models) |
| generate_psd | Generates the power spectral density matrix, corresponding to the given point-wise function) |
| cgn_rand: | Generate a colored gaussian random noise, with the given power spectral density. |
Generates the power spectral density matrix, corresponding to the given point-wise function)
| sz | the dimensions of the output matrix |
| func | the function to apply to every grid point |
| scale | a scaling factor for the frequency spectrum |
| visualization | the output is intended to be used for visualization (In this case, the DC coefficient is in the center of the image) |
Generate a colored gaussian random noise, with the given power spectral density.
| sz | the size of the output matrix |
| P | the power spectral density, as generated by generate_psd with visualization parameter set to 0. |