Smallest Univalue Segment Assimilating Nucleus (SUSAN)¶
Library: FSL | Docker Image: brainlife/fsl
Function¶
Edge-preserving noise reduction using nonlinear filtering that smooths within tissue boundaries while preserving edges.
Modality: 3D or 4D NIfTI volume (structural or functional).
Typical Use: Noise reduction while preserving structural boundaries in functional or structural data.
Key Parameters¶
Key Points¶
Brightness threshold typically 0.75 * median intensity. Set dimensionality to 3 for 3D volumes. Better edge preservation than Gaussian smoothing.
Inputs¶
| Name | Type | Required | Label | Flag |
|---|---|---|---|---|
input |
File |
Yes | Input image | |
brightness_threshold |
double |
Yes | Brightness threshold (should be > noise and < edge contrast) | |
fwhm |
double |
Yes | Spatial extent (FWHM in mm) | |
dimension |
int |
No | Dimensionality (2=2D, 3=3D, default 3) | |
use_median |
int |
No | Use median (1) or mean (0) for brightness calculation (default 1) | |
n_usans |
int |
No | Number of USAN areas to use (0, 1, or 2) | |
output |
string |
Yes | Output filename |
Accepted Input Extensions¶
- input:
.nii,.nii.gz
Outputs¶
| Name | Type | Glob Pattern |
|---|---|---|
smoothed_image |
File |
$(inputs.output).nii.gz, $(inputs.output).nii, $(inputs.output) |
log |
File |
susan.log |
Output Extensions¶
- smoothed_image:
.nii,.nii.gz
Docker Tags¶
Available versions: latest, 6.0.4-patched2, 6.0.4-patched, 6.0.4, 6.0.4-xenial, 5.0.11, 6.0.0, 6.0.1, 5.0.9
Categories¶
- Functional MRI > FSL > Smoothing