RasterLite2 - Rasters in SQLite DB¶
New in version 2.2.
Driver short name
The above short name is not a typo. The RasterLite2 functionality is part of the SQLite / Spatialite RDBMS driver.
The SQLite driver allows reading and writing SQLite databases containing RasterLite2 coverages.
GDAL/OGR must be compiled with sqlite support and against librasterlite2 and libspatialite.
The driver is implemented a unified SQLite / SpatiaLite / RasterLite2 vector and raster capable driver.
This driver supports the
This driver supports georeferencing
This driver supports virtual I/O operations (/vsimem/, etc.)
A RasterLite2 filename can be specified as the connection string. If the file contains a single RasterLite2 coverage, this one will be exposed as the GDAL dataset. If the file contains multiple coverages, each one will be exposed as a subdataset with the syntax RASTERLITE2:filename:coverage_name. See the basic concepts of RasterLite2.
If a coverage is made of several sections, they will be listed as subdatasets of the coverage dataset, so as to be accessed individually. By default, they will be exposed as a unified dataset. The syntax of section-based dataset is RASTERLITE2:filename:coverage_name:section_id:section_name.
The driver supports creating new databases from scratch, adding new coverages to an existing database and adding sections to an existing coverage.
APPEND_SUBDATASET=YES/NO: Whether to add the raster to the existing file. If set to YES, COVERAGE must be specified. Default is NO (ie overwrite existing file)
COVERAGE=string: Coverage name. If not specified, the basename of the output file is used.
SECTION=string: Section name. If not specified, the basename of the output file is used.
COMPRESS=NONE/DEFLATE/LZMA/PNG/CCITTFAX4/JPEG/WEBP/CHARS/JPEG2000: Compression method. Default is NONE. See the information about supported codecs. Note that some codecs may not be available depending on how librasterlite2 has been built.
QUALITY=0 to 100: Image quality for JPEG, WEBP and JPEG2000 compressions. Exact meaning depends on the compression method. For WEBP and JPEG2000, the value 100 triggers the use of their lossless variants.
PIXEL_TYPE=MONOCHROME/PALETTE/GRAYSCALE/RGB/MULTIBAND/DATAGRID: Raster pixel type. Determines the photometric interpretation. See the information about supported pixel types. The driver will automatically determine an appropriate pixel type given the band characteristics.
BLOCKXSIZE=int_value. Block width. Defaults to 512.
BLOCKYSIZE=int_value. Block height. Defaults to 512.
NBITS=1/2/4. Force bit width. This will be by default gotten from the NBITS metadata item in the IMAGE_STRUCTURE metadata domain of the source raster band.
PYRAMIDIZE=YES/NO. Whether to build automatically build relevant pyramids/overviews. Defaults to NO. Pyramids can be built with the BuildOverviews() / gdaladdo.
Reading a RasterLite2 database with a single coverage:
Listing the subdatasets corresponding to the coverages of a RasterLite2 database with several coverages:
Reading a subdataset corresponding to a coverage:
Creating a RasterLite2 dataset from a grayscale image:
gdal_translate -f SQLite byte.tif byte.rl2
Creating a RasterLite2 dataset from a RGB image, and using JPEG compression:
gdal_translate -f SQLite rgb.tif rgb.rl2 -co COMPRESS=JPEG
Adding a RasterLite2 coverage to an existing SpatiaLite/RasterLite2 database:
gdal_translate -f SQLite rgb.tif rgb.rl2 -co APPEND_SUBDATASET=YES -co COVERAGE=rgb
Adding pyramids to a coverage:
gdaladdo rgb.rl2 2 4 8 16