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GDAL DEM processing

Source: R/gdalraster_proc.R
dem_proc.Rd

dem_proc() generates DEM derivatives from an input elevation raster. This function is a wrapper for the gdaldem command-line utility. See https://gdal.org/en/stable/programs/gdaldem.html for details.

Usage

dem_proc(
  mode,
  srcfile,
  dstfile,
  mode_options = DEFAULT_DEM_PROC[[mode]],
  color_file = NULL,
  quiet = FALSE
)

Arguments

mode

Character. Name of the DEM processing mode. One of hillshade, slope, aspect, color-relief, TRI, TPI or roughness.

srcfile

Filename of the source elevation raster.

dstfile

Filename of the output raster.

mode_options

An optional character vector of command-line options (see DEFAULT_DEM_PROC for default values).

color_file

Filename of a text file containing lines formatted as: "elevation_value red green blue". Only used when mode = "color-relief".

quiet

Logical scalar. If TRUE, a progress bar will not be displayed. Defaults to FALSE.

Value

Logical indicating success (invisible TRUE). An error is raised if the operation fails.

Note

Band 1 of the source elevation raster is read by default, but this can be changed by including a -b command-line argument in mode_options. See the documentation for gdaldem for a description of all available options for each processing mode.

Examples

## hillshade
elev_file <- system.file("extdata/storml_elev.tif", package="gdalraster")
out_file <- file.path(tempdir(), "storml_hillshade.tif")
dem_proc("hillshade", elev_file, out_file)
#> 0...10...20...30...40...50...60...70...80...90...100 - done.

ds <- new(GDALRaster, out_file)
plot_raster(ds)


ds$close()