terra (version 1.3-22)

RGB: Declare RGB channels

Description

With RGB you can get or set the layers to be used as Red, Green and Blue when plotting a SpatRaster. Currently, the sole benefit of this is that plot will send the object to plotRGB

With RGB2col you can convert a three-layer RGB SpatRaster into a single-layer SpatRaster with a color-table.

Usage

# S4 method for SpatRaster
RGB(x)
# S4 method for SpatRaster
RGB(x)<-value
# S4 method for SpatRaster
RGB2col(x, value, stretch=NULL, grays=FALSE, filename="", overwrite=FALSE, ...)

Arguments

x

SpatRaster

value

vector of three (or four) positive integers indicating the layers that are red, green and blue (and optionally a fourth transparancy layer). Or NULL to remove the RGB settings. With RGB2col, this argument can be missing if RGB(x) is not NULL

stretch

character. Option to stretch the values to increase contrast: "lin" (linear) or "hist" (histogram)

grays

logical. If TRUE, a gray-scale color-table is created

filename

character. Output filename

overwrite

logical. If TRUE, filename is overwritten

...

additional arguments for writing files as in writeRaster

Examples

# NOT RUN {
s <- rast(system.file("ex/logo.tif", package="terra"))   
RGB(s) <- c(1,2,3)
plot(s)
RGB(s) <- NULL
# }