Extract Wavelength

This function extracts a single reflectance band that is the closest to a user defined wavelength from a hyperspectral datacube, which is a Spectral_data class instance created while reading in with pcv.readimage with mode='envi'. This function is similar to the pcv.spectral_index functions which calculates and outputs standard spectral indices from a hyperspectral datacubes.

plantcv.hyperspectral.extract_wavelength(spectral_data, wavelength)

returns channel array (instance of the Spectral_data class)

  • Parameters:

    • spectral_data - Hyperspectral data instance
    • wavelength - Target wavelength value for band for extraction
  • Note:

    • This function will print out which wavelength was found to be closest to the target wavelength value input. Additionally, this metadata is available since the function outputs a spectral data class instance which has a method that stores the array type.
  • Example use:

    • Below

from plantcv import plantcv as pcv

# Set global debug behavior to None (default), "print" (to file), 
# or "plot" (Jupyter Notebooks or X11)
pcv.params.debug = "plot"

# Many plants absorb 430nm wavelength light. 
blue_array_obj = pcv.hyperspectral.extract_wavelength(spectral_data=spectral_array_obj, wavelength=430)

blue_array_obj.array_type

> The closest band found to 400nm is: 400.033

Grayscale array image

Screenshot

Array type

> 'index_430'

Source Code: Here