vegInd_RGB: Calculate RGB indices

In SchoenbergA/LEGION: artifical layer computing tool

Description

computes several indices based on RGB bands

Usage

vegInd_RGB(rgb, red = NULL, green = NULL, blue = NULL, indlist = "all")

Arguments

rgb	a RasterStack with RGB bands
red	the band/layer number of band 'red'
green	the band/layer number of band 'green'
blue	the band/layer number of band 'blue'
indlist	comma-separated character combinations of the desired indices. Select from "VVI","VARI","NDTI","RI","CI","BI","SI","HI","TGI","GLI","NGRDI", default=all. See details

Details

available indices

• "VVI" Visible Vegetation Index (1 - abs((red - 30) / (red + 30))) * (1 - abs((green - 50) / (green + 50))) *(1 - abs((blue - 1) / (blue + 1)))

• "VARI" Visible Atmospherically Resistant Index (green-red)/(green+red-blue)

• "NDTI" Normalized Difference Turbidity Index (red-green)/(red+green)

• "RI" Redness index (red2/(blue*green3)

• "CI" Soil Colour Index (red-green)/(red+green)

• "BI" Brightness Index sqrt((red2+green2+blue*2)/3)

• "SI" Spectra Slope Saturation Index (red-blue)/(red+blue)

• "HI" Primary Colours Hue Index (2*red-green-blue)/(green-blue)

• "TGI" Triangular Greenness Index (-0.5*(190*(red - green)- 120*(red - blue))

• "GLI" Green Leaf Index (2green-red-blue)/(2green+red+blue)

• "NGRDI" Normalized Green Red Difference Index (green-red)/(green+red)

Value

returns a RasterStack with the selected indices

Author(s)

Andreas Schönberg

References

The IDB Project (2020): Index Database (https://www.indexdatabase.de/)

Examples

### load data
extpath <-system.file("extdata","lau_mspec.tif",package = "LEGION")
mspec <- raster::stack(extpath)
names(mspec)<- c("blue","green","red","nir")
### compute all vegetation indizes
x <-LEGION::vegInd_RGB(mspec,3,2,1)
plot(x)
### select specific vegetation indices
vi <-c("VVI","SI","GLI")
y <-LEGION::vegInd_RGB(mspec,3,2,1,indlist=vi)
plot(y)

SchoenbergA/LEGION documentation built on Jan. 31, 2021, 10:12 a.m.