mosaic_reproject_resample {OtsuFire} | R Documentation |
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)