mosaic_reproject_resample: Mosaic, Reproject, and Resample Burned Area Tiles

In OtsuFire: Fire Scars, Severity and Regeneration Mapping Using 'Otsu' Thresholding

Mosaic, Reproject, and Resample Burned Area Tiles

Description

This function creates a seamless mosaic from multiple raster tiles (e.g., RBR and DOY composites), masks them with a shapefile (e.g., Iberian Peninsula), reprojects the mosaic to a specified CRS (default: EPSG:3035), and resamples it to a target resolution (default: 90m).

It assumes the input rasters are two-band GeoTIFFs: - Band 1: RBR (Relative Burn Ratio) - Band 2: DOY (Day of Year of fire)

Usage

mosaic_reproject_resample(
  folder_path,
  mask_path,
  year = NULL,
  raster_pattern = "IBERIAN_MinMin_all_year_*.tif",
  crs_target = "EPSG:3035",
  res_target = 90,
  nodata_value = -9999
)

Arguments

folder_path	Character. Path to the folder containing the raster tiles.
mask_path	Character. Path to a polygon shapefile used to mask the rasters (e.g., burnable area mask).
year	Integer or character. Year label used for naming output files. If NULL, uses folder name.
raster_pattern	Character. Regex pattern to identify input raster tiles. Default: 'IBERIAN_MinMin_all_year_*.tif'.
crs_target	Character. EPSG code string for the target CRS to reproject (default: "EPSG:3035").
res_target	Numeric. Target spatial resolution in meters. Default: 90.
nodata_value	Numeric. NoData value to assign to missing values. Default: -9999.

Details

The function uses 'gdalbuildvrt' and 'gdalwarp' for efficient VRT-based mosaicking and reprojection. Steps: 1. Apply spatial mask to each raster tile. 2. Create VRT mosaic. 3. Reproject and resample the mosaic with 'gdalwarp'. 4. Clean NoData values and assign band names ('rbr', 'doy'). 5. Save compressed GeoTIFF output.

Value

Character. Full path to the final resampled GeoTIFF mosaic.

Note

Examples require large external raster files (hosted on Zenodo) and depend on external software (Python, GDAL). Therefore, they are wrapped in dontrun to avoid errors during R CMD check and to ensure portability.

Examples

## Not run: 
mosaic_reproject_resample(
  folder_path = "ZENODO/exdata",
  mask_path = "ZENODO/exdata/iberian_peninsula_proj_final.shp",
  year = 2012,
  raster_pattern = "IBERIAN_MinMin_all_year_2012_*.tif",
  crs_target = "EPSG:3035",
  res_target = 90
)

## End(Not run)

OtsuFire documentation built on June 13, 2025, 3:01 a.m.