mmand (version 0.1.2)

morphology: Standard mathematical morphology operations

Description

These functions provide standard mathematical morphology operations, which can be applied to array data with any number of dimensions.

Usage

erode(x, kernel)
dilate(x, kernel)
opening(x, kernel)
closing(x, kernel)

Arguments

x

An object that can be coerced to an array, or for which a morph method exists.

kernel

An array representing the kernel to be used. See shapeKernel for functions to generate a suitable kernel.

Value

• A morphed array with the same dimensions as the original array.

Details

The erode function uses the kernel as an eraser, centring it on each zero-valued voxel, which has the effect of eroding the extent of nonzero areas. Dilation has the opposite effect, extending the nonzero regions in the array. Opening is an erosion followed by a dilation, and closing is a dilation followed by an erosion, using the same kernel in both cases.

See Also

morph for the function underlying all of these operations, kernels for kernel-generating functions, binarise for binarising an array, and gaussianSmooth for smoothing. The EBImage Bioconductor package also supplies functions to perform these operations, and may be slightly faster, but only works in two dimensions.

Examples

x <- c(0,0,1,0,0,0,1,1,1,0,0)
k <- c(1,1,1)
erode(x,k)
dilate(x,k)