Apply a binary mask raster to an input raster

Reads input_path and mask_path tile-by-tile (one row at a time) and writes the result to output_path. Pixels where the mask equals 0 are replaced with NaN in the output; all other pixels retain their original values (with any GDAL scale/offset applied).

Usage

apply_mask_cpp(input_path, mask_path, output_path)

Arguments

input_path

Character string: path to a GDAL-readable raster (any number of bands).

mask_path

Character string: path to a single-band GDT_Byte mask raster (e.g., produced by rasterize_mask_cpp).

output_path

Character string: file path where the output Float64 GeoTIFF will be written (created or overwritten).

Value

Invisibly returns NULL. The side effect is the creation of the masked raster at output_path.

Details

This function is the low-level C++ entry point. Most users should call the higher-level create_mask wrapper instead.

Stops with an informative error if the package was built without GDAL support or if the mask and input dimensions differ.

See also

create_mask, rasterize_mask_cpp

Examples

# \donttest{
if (has_gdal()) {
  # Requires GDAL support at build time.
  ref    <- system.file("extdata", "tiny.tif", package = "xbioclim")
  poly   <- tempfile(fileext = ".geojson")
  mask   <- tempfile(fileext = ".tif")
  output <- tempfile(fileext = ".tif")
writeLines(
  '{"type":"FeatureCollection","features":[{"type":"Feature",
    "geometry":{"type":"Polygon","coordinates":[[[0,0],[1,0],[1,1],[0,1],[0,0]]]},
    "properties":{}}]}',
  poly)
  rasterize_mask_cpp(poly, ref, mask)
  apply_mask_cpp(ref, mask, output)
}
#> Warning: /tmp/RtmpRzND6Y/file31e6716919d0.tif: No such file or directory (GDAL error 4)
#> NULL
# }