Contents
What is FLAASH Atmospheric Correction?
FLAASH is a first-principles atmospheric correction tool that corrects wavelengths in the visible through near-infrared and shortwave infrared regions, up to 3 µm. Water vapor and aerosol retrieval are only possible when the image contains bands in appropriate wavelength positions.
How do you do atmospheric correction in ENVI?
From the Toolbox, select Radiometric Correction > Thermal Atmospheric Correction. Select an input file and perform optional spatial and spectral subsetting, then click OK. The Thermal Atm Correction Parameters dialog appears. Enter the Data Scale Factor needed to scale your data to units of W/m2/μm/sr.
What is dark object subtraction?
Dark object subtraction searches each band for the darkest pixel value. Assuming that dark objects reflect no light, any value greater than zero must result from atmospheric scattering. The scattering is removed by subtracting this value from every pixel in the band.
What is empirical line correction?
The empirical line method is an atmospheric correction technique that provides an alternative to radiative transfer modelling approaches. It offers a relatively simple means of surface reflectance calibration, providing that a series of invariant-in-time calibration target measurements are available.
Why radiometric correction is required?
radiometric corrections aim to precisely estimate the reflectivity of an environment, by compensating for the distortions related to the used antenna system, to positioning errors and certain characteristics of the electronic components.
What is DOS atmospheric correction?
DOS is ” Dark Object Subtraction” method for atmospheric correction, 1-4 represents various sets of input parameters like atmospheric transmittance (Tau) used. DOS is one of the most common used atmospheric correction method.