Didger can import ESRI Arc/Info binary grid files .ADF.
The Arc/Info Binary Grid format is the internal working format of the Arc/Info Grid product. This format should not be confused with the Arc/Info ASCII Grid format which is the interchange format for grids.
A grid coverage (or data set) actually consists of a number of files. A grid normally lives in its own directory named after the grid. For example, the grid nwgrd1 lives in the directory nwgrd1, and has the following component files:
nwgrd1/dblbnd.adf - file containing the bounds of the grid.
nwgrd1/hdr.adf - header file
nwgrd1/sta.adf - statistics file
nwgrd1/vat.adf - value attributes file
nwgrd1/w001001.adf - the actual raster data file
nwgrd1/w001001x.adf - file containing file offset and size of each block in the raster data file.
No import options dialog is displayed.
Didger does not currently export this format.
Note: ESRI ArcMap or ArcCatalog requires that .ADF files do not have spaces in the file names. If you want to include a space, it is recommended that you replace all spaces with an underscore (_).
File Format Chart