Self-Shading Correction

Description

Applies self-shading correction to water-leaving reflectance measurements collected through the skylight-blocked approach, following Yu et al. (2021).

• Valid for wavelengths between 300 and 1000 nm. (Extending beyond this range requires additional water backscattering data)
• Input reflectance must include bands at or near 440 nm, 550 nm, and 750 nm. (The closest available wavelengths are used)

Home page: https://github.com/yulunwu8/selfshadingcorrection

Installation

pip3 install selfshadingcorrection

Quick Start

import selfshadingcorrection as ssc

file_in = 'Rw_shaded.csv'        # Path to input CSV with shaded water-leaving reflectance.
file_out = 'Rw_corrected.csv'    # Path to output CSV with self-shading-corrected reflectance.
start_column = 10                # Index of the first reflectance column (0-based).
sza_column = 'sza'               # Name of the column containing solar zenith angle (in degrees).
radius = 0.05                    # Radius of the instrument cone (in meters).

ssc.run(file_in, file_out, start_column, sza_column, radius)

Input Data Format

• Sample: See example input and output data at in the selfshadingcorrection/tests folder.
• Metadata columns (before start_column): Must include a column for the solar zenith angle in degrees. All metadata columns will be copied to the output as is.
• Reflectance columns (starting at start_column): Column names should follow the format Rxxx, where xxx is the wavelength in nm.
• Reflectance values: Bi-hemispherical water-leaving reflectance (dimensionless).

Reference

Yu, X., Lee, Z., Shang, Z., Lin, H., Lin, G., 2021. A simple and robust shade correction scheme for remote sensing reflectance obtained by the skylight-blocked approach. Opt. Express 29, 470. https://doi.org/10.1364/OE.412887

Others

For questions and suggestions (which I'm always open to!), please open an issue or email Yulun at yulunwu8@gmail.com