Script to grow a set of regions in a volumetric dataset using modal

Usage Example

 @ROI_modal_grow                                      \
   -input  mydset.nii.gz                              \
   -outdir myoutdir                                   \
   -niters 5                                          \
   -mask mymask.nii.gz                                \
   -prefix rmg_name

Note only the input dataset and the number of iteration levels
are required.


    -input input_dset   :required input dataset. This dataset should be
                         set of integer values. The program mostly assumes
                         approximate isotropic voxels.

    -outdir outdirname  :directory name for output. All output goes to
                         this directory. Default is rmgrow.

    -niters nn          :number of iterations for modal growth -
                         something like dilation level here - generally
                         this will make sense for values from about 1-10

    -mask maskset       :mask dataset at same grid as the input dataset.
                         this could be a dilated version of the original mask
                         or a larger region like a cortical ribbon mask.
                         Not required but often desirable.

    -prefix baseprefix  :base name of final output dataset, i.e. baseprefix.nii.gz
                         Default is rmg, so output would be rmg.nii.gz

    -NN [1,2,3]         :neighborhood type using in finding mode,
                         1 - facing neighbors, 2-edges, 3-corners

Also see these programs with these similar functions:
   3dROImaker - grows regions using regular dilation iteratively
   3dmask_tool - dilates and erodes sets of input files or a single output mask
   3dmerge, 3dAutomask, 3dcalc - all can do dilation
   3dLocalstat - modal and nonzero modal smoothing
   ROIgrow - dilates surface ROI (patches) within the mesh of the surface