# ISG – International Service for the Geoid

New in version 3.1.

Driver short name

ISG

Driver built-in by default

This driver is built-in by default

Supports reading grids in the International Service for the Geoid text format, used for number of geoid models at http://www.isgeoid.polimi.it/Geoid/reg_list.html

Format specification is at http://www.isgeoid.polimi.it/Geoid/ISG_format_20160121.pdf

NOTE: Implemented as `gdal/frmts/aaigrid/aaigriddataset.cpp`.

## Driver capabilities

Supports Georeferencing

This driver supports georeferencing

Note

WGS84 will always be arbitrarily reported as the interpolation CRS of the grid. Consult grid documentation for exact CRS to apply.

Supports VirtualIO

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