MiraMon Raster

Added in version 3.12.

Driver short name

MiraMonRaster

Driver built-in by default

This driver is built-in by default

This driver is capable of reading raster files in the MiraMon format. Write support is expected soon.

A look-up table of MiraMon and EPSG Spatial Reference Systems allows matching identifiers in both systems.

Driver capabilities

Supports Georeferencing

This driver supports georeferencing

Supports VirtualIO

This driver supports virtual I/O operations (/vsimem/, etc.)

Overview of MiraMon format

The MiraMon .img format is a binary raster format with rich metadata stored in a sidecar .rel file. More information is available in the public specification.

By specifying either the name of the .rel metadata file or the name of any .img band file, the driver will automatically use the associated .rel file.

  • REL file: This metadata file governs how all bands are interpreted and accessed. It contains metadata including band names, number of rows and columns, data type, compression information (either global or per band) and others. So, a MiraMon dataset can include multiple bands, all linked through a single .rel file. Whether the name of one of the dataset's .img files or the .rel file is provided, the result will be the same: all bands will be considered. If a layer contains an old .rel format file (used in legacy datasets), a warning will be issued explaining how to convert it into the modern .rel 4 format. Next are the main characteristics of a MiraMon raster dataset band:

  • IMG file: Stores the raw raster data. The data type may vary: - Bit: 1 bit. Range: 0 or 1. Converted to byte GDAL type. - Byte: 1 byte, unsigned. Range: 0 to 255 - Short: 2 bytes, signed. Range: -32 768 to 32 767 - UShort: 2 bytes, unsigned. Range: 0 to 65 535 - Int32: 4 bytes, signed. Range: -2 147 483 648 to 2 147 483 647 - UInt32: 4 bytes, unsigned. Range: 0 to 4 294 967 295 - Int64: 8 bytes, signed integer - UInt64: 8 bytes, unsigned integer - Real: 4 bytes, floating-point - Double: 8 bytes, double precision floating-point

Color Table

MiraMon raster bands may include a color table in dBASE (DBF) format, or in extended DBF format, if necessary. If present, it will be exposed through the GetRasterColorTable() method. More information is available in the public specification.

Attribute Table

MiraMon raster bands may also include an attribute table in the same format as color table.. If available, it will be exposed as a GDAL Raster Attribute Table (RAT) via GetDefaultRAT(). This allows applications to retrieve additional metadata associated with each raster value, such as class names or descriptions.

Metadata

Metadata from MiraMon raster datasets are exposed through the "MIRAMON" domain. Only a subset of the metadata is used by the driver to interpret the dataset (e.g., georeferencing, data type, etc), but all other metadata entries are preserved and accessible via GetMetadata("MIRAMON").

This allows applications to access additional information embedded in the original dataset, even if it is not required for reading or displaying the data.

Encoding

When reading MiraMon DBF files, the code page setting in the .dbf header is used to translate string fields to UTF-8, regardless of whether the original encoding is ANSI, OEM or UTF-8.

REL files are always encoded in ANSI.

Open options

None.

Dataset creation options

None.

See Also