Calibrate Raw HSI Data to Reflectance

Applies dark current subtraction and white reference normalization: R(x,y,lambda) = (raw - dark) / (white - dark). Values are clamped to [0, 1] unless clamp = FALSE.

Usage

hs_calibrate(cube, dark, white, clamp = TRUE)

Arguments

cube

An hsi_cube object with raw data.

dark

An hsi_cube object or 3D array representing the dark reference (lens cap measurement).

white

An hsi_cube object or 3D array representing the white reference (Spectralon panel measurement).

clamp

Logical. Clamp output to [0, 1]. Default TRUE.

Value

An hsi_cube object with reflectance values.

Examples

cube <- hs_simulate_cube(rows = 10, cols = 10, noise_sd = 0)
dark <- hsi_cube(array(0.01, dim(cube$data)), cube$wavelengths)
white <- hsi_cube(array(0.95, dim(cube$data)), cube$wavelengths)
cal <- hs_calibrate(cube, dark, white)
range(cal$data)
#> [1] 0.04255319 0.73404255