Deciphering a USGS DEM file

I came across this in Evernote and figured I'd share it in case some poor soul should ever have to dig into the guts of the DEM file format like I had to a few years ago. As you can see below (click on image for a PDF), it's a pretty cryptic and nasty mess in there.

The DEM I used was derived from GTOPO 1km elevation data. The source data was converted to a tiff in ArcGIS, then converted to a DEM using the following GDAL command:

D:\Data\GTOPO>gdal_translate -of USGSDEM raster30.tif raster30.dem

I used the National Map - Standards for Digital Elevation Models as a reference to figure all of this out.


Written on September 28, 2015