CereusDB API Documentation
    Preparing search index...

    Raster Functions

    Raster support is available in @cereusdb/full only. It combines two sets of SedonaDB functions:

    • the core raster catalog from sedona-raster-functions: metadata, georeference, pixel geometry, band values and predicates such as RS_Width, RS_CRS, RS_PixelAsPolygon and RS_Intersects
    • the GDAL-backed functions from sedona-raster-gdal, which run GDAL's algorithms (warp, rasterize, polygonize, GeoTIFF encoding) inside the WebAssembly module

    Rasters enter SQL from the host side, as in-memory rasters:

    const bytes = new Uint8Array(await (await fetch('/data/elevation.tif')).arrayBuffer());
    db.registerGeoTIFF('elevation', bytes);

    const rows = await db.sqlJSON('SELECT RS_Width(raster) AS width FROM elevation');

    registerFile() accepts .tif and .tiff files from the File API as well. Inside SQL, RS_FromGDALRaster decodes GeoTIFF bytes from a binary column or expression.

    Function What it does
    RS_AsGeoTiff Encode a raster as GeoTIFF bytes
    RS_AsRaster Rasterize a geometry onto the grid of a reference raster
    RS_Clip Clip a raster to a geometry, setting outside pixels to nodata
    RS_FromGDALRaster Decode raster bytes (GeoTIFF in this build) into a raster
    RS_MetaData Return raster metadata as a struct
    RS_Polygonize Convert a band into polygons of connected pixel-value regions
    RS_ReprojectMatch Warp a raster onto the grid and CRS of another raster
    RS_Resample Resample onto a new pixel grid (size, pixel size or snapped origin)
    RS_Tile Split a raster into a grid of fixed-size tiles
    RS_ZonalStats Compute one statistic of a band within a geometry
    RS_ZonalStatsAll Compute all zonal statistics of a band within a geometry 
    SELECT RS_ZonalStats(
  raster,
  ST_GeomFromText('POLYGON ((60 90, 160 90, 160 190, 60 190, 60 90))', 'OGC:CRS84'),
  1,
  'mean'
) AS mean_value
FROM elevation;

    -- Round-trip through GeoTIFF bytes
SELECT RS_Width(RS_FromGDALRaster(RS_AsGeoTiff(raster))) FROM elevation;
    • Formats: the WebAssembly GDAL build includes the GeoTIFF, MEM and VRT raster drivers. RS_FromGDALRaster and RS_AsGeoTiff therefore read and write GeoTIFF (including Cloud Optimized GeoTIFF); other formats such as PNG, JPEG files or NetCDF fail to decode.
    • GeoTIFF compression: None, Deflate, LZW, PackBits, JPEG, LERC, LERC_DEFLATE, ZSTD and LERC_ZSTD are supported. Files using other codecs, such as LZMA, WebP or JPEG XL, are rejected with an error that names the missing codec.
    • RS_FromPath is not available. It opens files and URLs through GDAL, and the browser build has neither a local filesystem nor GDAL's /vsicurl network access. Fetch the bytes in JavaScript and use registerGeoTIFF() instead.
    • RS_AsRaster requires a reference raster without skew, and the geometry must carry a CRS when the reference raster has one.
    • All raster processing runs on the thread that created the database. Create the database in a Web Worker to keep large rasters off the main thread.

    Settings

    Member Visibility

    On This Page

    Raster Functions