ISG -- International Service for the Geoid

Added in version 3.1.

Driver short name


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

Format specification is at

NOTE: Implemented as aaigriddataset.cpp.

Driver capabilities

Supports Georeferencing

This driver supports georeferencing


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.)