minnaert_samp: Topographic correction for satellite imagery using Minnaert...

In yinscapital/sat-locat-reference-team-lucc: TEAM land use and cover change data processing toolkit

Description

Perform topographic correction using the Minnaert method. This code is modified from the code in the landsat package written by Sarah Goslee. This version of the code has been altered from the landsat version to allow the option of using a sample of pixels for calculation of k in the Minnaert correction (useful when dealing with large images).

Usage

minnaert_samp(x, slope, aspect, sunelev, sunazimuth, IL.epsilon = 1e-06,
  slopeclass = NULL, coverclass = NULL, sampleindices = NULL,
  DN_min = NULL, DN_max = NULL)

Arguments

x	image as a RasterLayer
slope	the slope in radians as a RasterLayer
aspect	the aspect in radians as a RasterLayer
sunelev	sun elevation in degrees
sunazimuth	sun azimuth in degrees
IL.epsilon	a small amount to add to calculated illumination values that are equal to zero to avoid division by zero resulting in Inf values
slopeclass	the slope classes to calculate k for (in radians), or NULL, in which case an algorithm will be used to choose reasonable defaults for the given image. If provided, slopeclass should be a list of slope class limits. For example: c(1, 5, 10, 15, 20, 25, 30, 45) * (pi/180)
coverclass	used to calculate k for specific cover class (optional) as RasterLayer
sampleindices	(optional) row-major indices of sample pixels to use in the calculation of k values for the Minnaert correction. See gridsample.
DN_min	minimum allowable pixel value after correction (values less than DN_min are set to NA)
DN_max	maximum allowable pixel value after correction (values less than DN_max are set to NA)

Details

See the help page for minnaert in the landsat package for additional details on the parameters.

Value

RasterLayer with topographically corrected data

Author(s)

Sarah Goslee and Alex Zvoleff

References

Sarah Goslee. Analyzing Remote Sensing Data in R: The landsat Package. Journal of Statistical Software, 2011, 43:4, pg 1–25. http://www.jstatsoft.org/v43/i04/

yinscapital/sat-locat-reference-team-lucc documentation built on May 14, 2019, 11:09 a.m.