Source code for eoreader.bands.spectral_bands

# -*- coding: utf-8 -*-
# Copyright 2024, SERTIT-ICube - France, https://sertit.unistra.fr/
# This file is part of eoreader project
#     https://github.com/sertit/eoreader
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
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# distributed under the License is distributed on an "AS IS" BASIS,
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""" Spectral Bands """
import numpy as np

from eoreader.bands.band_names import SpectralBandNames
from eoreader.bands.bands import Band, BandMap
from eoreader.bands.mappings import EOREADER_TO_SPYNDEX_DICT
from eoreader.exceptions import InvalidTypeError
from eoreader.stac import CENTER_WV, FWHM, SOLAR_ILLUMINATION, WV_MAX, WV_MIN


[docs]class SpectralBand(Band): """ Spectral Band object. Based on STAC band object. See `here <https://github.com/stac-extensions/eo/#band-object>`_ for more information. """ @staticmethod def _from_nm_microm(wavelength: float, thresh=100) -> float: """ Convert wavelength in nanometers (if > 100) to micrometers Args: wavelength (float): Wavelength in nanometers Returns: float: Wavelength in micrometers """ if wavelength and wavelength > thresh: wavelength = np.round(wavelength / 1000.0, 6) return wavelength
[docs] def __init__(self, eoreader_name, **kwargs): self.center_wavelength = None """ STAC :code:`center_wavelength`. The center wavelength of the band, in micrometers (μm). """ self.full_width_half_max = None """ STAC :code:`full_width_half_max`. Full width at half maximum (FWHM). The width of the band, as measured at half the maximum transmission, in micrometers (μm). """ if WV_MAX in kwargs and WV_MIN in kwargs: wv_max = self._from_nm_microm(kwargs[WV_MAX]) wv_min = self._from_nm_microm(kwargs[WV_MIN]) assert wv_max > wv_min self.full_width_half_max = np.round(wv_max - wv_min, 6) self.center_wavelength = np.round( wv_min + self.full_width_half_max / 2.0, 6 ) else: self.center_wavelength = self._from_nm_microm(kwargs.get(CENTER_WV)) self.full_width_half_max = self._from_nm_microm(kwargs.get(FWHM), thresh=1) self.solar_illumination = kwargs.get(SOLAR_ILLUMINATION) """ STAC :code:`solar_illumination`. The solar illumination of the band, as measured at half the maximum transmission, in W/m2/micrometers. """ # Initialization from the super class super().__init__(eoreader_name, **kwargs) # Set names try: self.eoreader_name = SpectralBandNames.convert_from(eoreader_name)[0] self.common_name = SpectralBandNames.eoreader_to_stac(self.eoreader_name) except TypeError: raise InvalidTypeError
def _to_repr_constellation_specific(self) -> list: """ Representation specific to the constellation Returns: list: Representation list (constellation specific) """ repr_str = [] if self.center_wavelength is not None: repr_str.append( f"\tCenter wavelength (nm): {self.center_wavelength * 1000}" ) if self.full_width_half_max is not None: repr_str.append(f"\tBandwidth (nm): {self.full_width_half_max * 1000}") if self.solar_illumination is not None: repr_str.append( f"\tSolar Illumination (W/m2/micrometers): {self.solar_illumination}" ) return repr_str
# too many ancestors # pylint: disable=R0901
[docs]class SpectralBandMap(BandMap): """Spectral band map class"""
[docs] def __init__(self) -> None: super().__init__({band_name: None for band_name in SpectralBandNames})
[docs] def map_bands(self, band_map: dict) -> None: """ Mapping band names to specific satellite band numbers, as strings. .. code-block:: python >>> ob = SpectralBandMap() >>> ob.map_bands({ CA: '01', BLUE: '02', GREEN: '03', RED: '04', VRE_1: '05', VRE_2: '06', VRE_3: '07', NIR: '08', WV: '09', SWIR_1: '11', SWIR_2: '12' }) Args: band_map (dict): Band mapping as {SpectralBandNames: Band number for loading band} """ for band_name, band in band_map.items(): if not isinstance(band, SpectralBand): band = SpectralBand( eoreader_name=band_name, name=band, id=band, spyndex_name=EOREADER_TO_SPYNDEX_DICT.get(band_name), ) if band_name not in self._band_map or not isinstance( band_name, SpectralBandNames ): raise InvalidTypeError( f"{band_name} should be a SpectralBandNames object" ) # Set number self._band_map[band_name] = band
def __repr__(self): bands = [band for band in self._band_map.values() if band is not None] try: bands.sort(key=lambda x: int(x.id)) except ValueError: bands.sort(key=lambda x: x.id) return "\n".join([band.__repr__() for band in bands])