convRad2Ref: Convert a band's scaled counts or radiance values to...

In environmentalinformatics-marburg/satellite: Handling and Manipulating Remote Sensing Data

Convert a band's scaled counts or radiance values to reflectance

Description

Convert a band's scaled counts to reflectance using a simple linear conversion without any kind of atmospheric correction etc.

Usage

## S4 method for signature 'Satellite'
convRad2Ref(x, szen_correction = "TRUE")

## S4 method for signature 'RasterStack'
convRad2Ref(x, mult, add, szen)

## S4 method for signature 'RasterLayer'
convRad2Ref(x, mult, add, szen)

Arguments

x	An object of class Satellite, raster::RasterStack or raster::RasterLayer providing radiance values.
szen_correction	Logical; if TRUE, sun zenith correction is being applied.
mult	Multiplicative coefficient for value transformation (i.e. slope).
add	Additive coefficient for value transformation (i.e. offset)
szen	Cosine of solar zenith angle.

Details

The conversion functions are taken from USGS' Landsat 8 Data Users Handbook which is available online at https://www.usgs.gov/landsat-missions/landsat-8-data-users-handbook.

If the sensor does not provide linear conversion coefficients for reflectance computation, the reflectance is calculated using the solar irradiance following the functions taken from USGS' Landsat 7 manual, chapter 11.3.2, which is available online at https://www.usgs.gov/media/files/landsat-7-data-users-handbook.

Value

If x is a Satellite object, a Satellite object with added converted layers;
if x is a raster::Raster* object, a raster::Raster* object with converted layer(s).

See Also

calcAtmosCorr for conversions of scaled counts to physical units including a scene-based atmospheric correction.

Examples

path <- system.file("extdata", package = "satellite")
files <- list.files(path, pattern = glob2rx("LC08*.TIF"), full.names = TRUE)
sat <- satellite(files)  
sat <- convRad2Ref(sat)

# If you use a raster layer, supply required meta information
bcde <- "B002n"
convRad2Ref(x = getSatDataLayer(sat, bcde),
            mult = getSatRADM(sat, bcde),
            add = getSatRADA(sat, bcde))

environmentalinformatics-marburg/satellite documentation built on Feb. 10, 2024, 2:56 p.m.