Implements Smallest Univalue Segment Assimilating Nucleus (SUSAN) noise reduction technique from FSL
susan(file, outfile = NULL, retimg = TRUE, reorient = FALSE,
intern = FALSE, bthresh = 0.1, sigma = 3, dimg = c(3, 2),
use_median = FALSE, n_usans = c(0, 1, 2), extra.scans = list(),
opts = "", verbose = TRUE, ...)
(character) image to be manipulated
(character) resultant image name (optional)
(logical) return image of class nifti
(logical) If retimg, should file be reoriented when read in?
Passed to readnii
.
(logical) to be passed to system
brightness threshold and should be greater than noise level and less than contrast of edges to be preserved.
spatial size (sigma i.e. half-width) of smoothing in mm.
dimensionality (2 or 3) depending on whether smoothing is to be within-plane (2) or fully 3D (3).
determines whether to use a local median filter in the cases where single-point noise is detected (0 or 1).
determines whether the smoothing area (USAN) is to be found from secondary images (0 1 or 2).
List of extra scans for USAN. List of
n_usans
elements, where each element has 2 named objects
bthresh
and filename
(character) operations to be passed to susan
, not
currently used.
(logical) print out command before running
additional arguments passed to fslcmd
.
If retimg
then object of class nifti. Otherwise,
Result from system command, depends if intern is TRUE or FALSE.
S.M. Smith and J.M. Brady. SUSAN -a new approach to low level image processing. International Journal of Computer Vision, 23(1):45-78, May 1997.