The ERDAS Imagine Image format is the raster data format used with the ERDAS Imagine software product line.

Import

Typical imagery includes satellite data as well as land coverages. For multi-band images and grayscale images, Global Mapper will automatically apply a two-standard deviation contrast stretch in order to generate an aesthetically pleasing image with no intervention. If present, the first 3 bands will be used the generate the image, with band 1 being red, band 2 being green, and band 3 being blue.

Export

The Export Erdas Imagine command allows the user to export any loaded raster, vector, and elevation grid data sets to an Erdas Imagine file.

Export Erdas Imagine files from the File> Export menu by choosing Export Elevation Grid Format... or Export Raster/ Image Format.... and specifying Erdas Imagine file as the Export Format. Individual layers can also be exported from the Control Center by right-click on the layer and going to Layer > EXPORT. Multiple files can be batch converted to and from the format from the Batch Convert/Reproject tool.

When selected, the command displays the Erdas Imagine Export Options dialog which allows the user to setup the export.

The dialog consists of a General options panel which allows the user to set up the pixel spacing and format, a Tiling Panel, and an Export Bounds panel which allows the user to set up the portion of the loaded data they wish to export.

File Type

• 8-bit Palette Image - This option generates a 256-color raster file with 8-bits per pixel. The Palette options described below will apply in this case. This option will generate a relatively small output file, at the expense of some color fidelity depending on the palette that you choose. The image data will be compressed using the PackBits compression algorithm.
• 24-bit RGB - This option generates a raster file with 24-bits per pixel. Uncompressed images generated with this option will be at least 3 times the size of those generated with the 8-bit Palette option, but the colors in the image will exactly match what you see on the screen.
• Elevation (16-bit integer samples) - This option generates an elevation grid using the currently loaded elevation grid data sets. Elevation samples will be stored as signed 16-bit integers.
• Elevation (32-bit floating point samples) - This option generates an elevation grid using the currently loaded elevation grid data sets. Elevation samples will be stored as 32-bit floating point values.
• Multi-band - This option generates a raster file with 1 or more bands of data at either 8-, 16-, or 32-bits per band of data. This option is very useful when working with multi-spectral imagery with more than 3 bands of data, such as RGBI, Landsat imagery, or data sets with more than 8 bits per color channel. After selecting this option additional dialogs will be presented allowing for further setup of the multi-band export by choosing the input sources for each band in the output image.

Palette

When generating a 8-bits Palette image, it is necessary to select a palette indicates what 256 colors will be used to describe the image being exported.

For more information on available palettes see GeoTIFF

Vertical Units

The Vertical Units field allows the user to select the vertical units to use when exporting elevation data (i.e. meters or feet). Any input data not in the selected vertical units will be automatically converted on export.

Save Map Layout

The distance scale, elevation legend, and coordinate grid will be saved to the file (except when exporting elevation grids) if they are configured to show up in the main display.

Save Vector Data if Displayed

Any loaded vector data that is configured to show up in the main display will be saved to the image file (except when exporting elevation grids).

Interpolate to fill small gaps in data

Any small areas with missing data will be filled in by interpolating the surrounding valid data using an IDW method out to a distance of 30 cells. This is useful for filling small gaps between adjacent tiles or small holes in elevation data.

Create Compressed File

Compression will decrease the file size when the file contains large homogenous areas.

Add Overview (Pyramid) Layers

Large images will render faster across applications if they also have pyramid layers generated.

ADVANCED: Block Size

ERDAS files contain an internal tilling, specified as a block size. The default and most common block size is 64 pixels. For more information see https://community.hexagongeospatial.com/t5/ERDAS-IMAGINE-Q-A/ERDAS-IMAGINE-img-Files/ta-p/704

ADVANCED: Elevation No-Data Value

Customize the no-data value when exporting an elevation grid format.

Format Updates

Below is a summary of recent changes to Erdas Imagine export: