Convert IMG Data to BIL with GDAL Scripts

These directions assume that gdal_translate.exe is in the path, or C:\Program Files\GDAL\.

Step

Description

Screenshot

Obtain IMG Data: Step 1

The primary method for downloading The National Map (TNM) raster IMG (3D Elevation Program (3DEP) 1-, 1/3-, or 1/9-arc-second) type of staged products is by using the new TNM download client (http://viewer.nationalmap.gov/basic/). Zoom to the area of interest. Select "Elevation Products (3DEP)" from the Datasets section on the left (1), then a subcategory (2) and IMG file format (3). Finally, click on the "Find Products" button (4) to bring up the available products.

Obtain IMG Data: Step 2

When the Available Products window appears, click on "Download" to download the IMG in a zip file. Once downloaded, unzip the file locally, making note of the location.

Obtain USGS Raster Conversion Scripts

A set of scripts for converting raster staged data is available at USGS_Raster_Conversion_Scripts. These should be downloaded and unzipped locally. (These directions are part of the how to documentation in that archive.)

Option 1: Drag and Drop IMG Download Folder

The GDAL_Convert_All_IMG_2_BIL.bat script takes a folder name as input and recursively scans that folder for all img files and attempts to create a BIL for each. In Windows Explorer, when you drag and drop a folder onto a batch file, the folder path is passed as the parameter to run that batch file with. Doing this produces a BIL in that same folder as the IMG data. The resulting image(s) will have the name GDAL_IMG_2_BIL.bil.

In order to use this method, download the GDAL scripts into a user-controlled directory with write permissions. Drag and drop the original IMG file from the same directory that the conversion script is located in.

Option 2: Run the GDAL_IMG_2_BIL.bat from the Command Line

The GDAL_IMG_2_BIL.bat file uses an IMG file location for the first parameter which is the source to convert. This script will not recursively scan the sub-directories to find the data, so the path must point to the actual IMG file. A second parameter that is optional allows you to specify the path and name of the output IMG file.

Since the second parameter is optional, the easiest way to run this is to drag and drop the IMG file onto the batch file. The directions for using this script are presented below:

USAGE: GDAL_IMG_2_BIL.bat <IMG Input File> [Output File Name]

<IMG Input File> (REQUIRED) This is the relative or full path to the IMG file that contains the source data.

[Output File Name] (OPTIONAL) This is the relative or full path to the output file that will be created. If this is not set, it will attempt to make a sub-folder under the current directory called BIL_Output, and a file in that folder called GDAL_IMG_2_BIL.bil.