erode_mask_vol: Erode 3D mask
In fMRItools: Routines for Common fMRI Processing Tasks

erode_mask_vol

R Documentation

Erode 3D mask

Description

Erode a volumetric mask by a certain number of voxel layers. For each layer, any in-mask voxel adjacent to at least one out-of-mask voxel is removed from the mask.

Usage

erode_mask_vol(vol, n_erosion = 1, out_of_mask_val = NA)

Arguments

`vol`	The 3D array to erode. The mask to erode is defined by all values not in `out_of_mask_val`.
`n_erosion`	The number of layers to erode the mask by. Default: `1`.
`out_of_mask_val`	A voxel is not included in the mask if and only if its value is in this vector. The first value of this vector will be used to replace eroded voxels. Default: `NA`. If `vol` is simply a logical array with `TRUE` values for in-mask voxels, use `out_of_mask_val=FALSE`.

Details

Diagonal voxels are not considered adjacent, i.e. the voxel at (0,0,0) is not adjacent to the voxels at (1,1,0) or (1,1,1), although it is adjacent to (1,0,0).