Apply a spectral pretransform before segmentation

Applies a column-wise pretransform to a spectra matrix before row-wise scaling and clustering. This is useful for benchmarking clustering behavior under simple nonlinear transforms such as asinh(), log1p(), or rank-based copula mappings.

Usage

pretransform_spectra(
  x,
  method = c("none", "asinh", "log1p", "signed_log1p", "copula_uniform",
    "copula_gaussian")
)

Arguments

x

Numeric matrix with one spectrum per row and one band per column.

method

Either a string naming a built-in transform or a function that takes a numeric matrix and returns a numeric matrix with the same dimensions. Built-in options are "none", "asinh", "log1p", "signed_log1p", "copula_uniform", and "copula_gaussian".

Value

A numeric matrix with the same dimensions as x.