ERDAS .gis or .lan formats are often used for raster images, for example, from Landsat Thematic Mapper (TM) satellite imagery.
To import from ERDAS .gis format:
Choose File-Import from the main menu.
In the Import dialog browse to the location of the file and double-click on the .gis file desired.
A table and an image will be created.
Open the image and Immediately launch Assign Initial Coordinate System in the Info pane to specify the correct initial projection for the image.
See the Example: Import ERDAS GIS with GDAL and Assign Coordinate System topic for a step-by-step example using GDAL.
Projections - Take care to find any available commentaries or metadata information that may accompany the .gis files in use. .gis files do not provide full projection information and will result in imports that do not correctly specify projection information. In that case, we will have to use whatever documentation we can find on the data set to learn what the correct projection should be so we can specify it using Assign Initial Coordinate System.
Assign Initial Coordinate System
Repair Initial Coordinate System
Example: Spectacular Images and Data from Web Servers
Example: An Imageserver Tutorial
Example: Import ERDAS GIS with GDAL and Assign Coordinate System - A multistep example that covers import of an unwieldy format using GDAL, followed by use of Assign Initial Coordinate System and Repair Initial Coordinate System to deal quickly with real-life complications.