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ANTsR (version 0.4.0)

rfSegmentation: A rfSegmentation function.

Description

Unsupervised image segmentation via random forests. An example.

Usage

rfSegmentation(featureMatrix, mask, labelimg = NA, ntrees = 100,
  verbose = FALSE)

Arguments

featureMatrix

input matrix of features matched to mask size n predictors in rf

mask

input antsImage mask

labelimg

input antsImage labelimage, optional for supervised seg

ntrees

number of rf trees

verbose

boolean

Value

list of n-probability images is output where n is number of classes

See Also

mrvnrfs

Examples

Run this code
# NOT RUN {
if ( usePkg("randomForest") ) {
img<-antsImageRead( getANTsRData("r16") ) %>% iMath("Normalize")
mask<-getMask( img )
segs<-kmeansSegmentation( img, k=3, kmask = mask)
fmat0 = t( antsrimpute( getNeighborhoodInMask( img, mask, c(2,2) ) ) )
fmat1 = t( antsrimpute( getNeighborhoodInMask(
  segs$probabilityimages[[1]], mask, c(2,2) ) ) )
fmat2 = t( antsrimpute( getNeighborhoodInMask(
  segs$probabilityimages[[2]], mask, c(2,2) ) ) )
fmat3 = t( antsrimpute( getNeighborhoodInMask(
  segs$probabilityimages[[3]], mask, c(2,2) ) ) )
fmat = cbind( fmat0, fmat1, fmat2, fmat3 )
# produces proximity between all voxel pairs
rfsegs<-rfSegmentation( fmat, verbose=FALSE )
lrr = lowrankRowMatrix( rfsegs, 10, faster = TRUE )
nv = eanatSelect( inmat=lrr, mask=mask, selectorScale=1.2,  cthresh=50,
  verbose=T, smooth=1 )
ee = eanatDef( lrr, mask, nvecs=nv, smooth=0., cthresh=50,
  its=2, verbose=TRUE )
eseg = eigSeg( mask, ee )
plot( img, eseg )
}
# }

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