GeoTiff Raster Files

Touchstone supports the import of GeoTiff raster files as map layers. You can then visualize your exposure data with the imported map layers and run Geospatial Analyses with the map layers. (You must have a license for Geospatial Analysis.)

You can import multi-band (for example, Landsat) or single-band (for example, DEM) GeoTIFF files into Touchstone. However, you can import only one band from the source file at one time; you select it from a list.

You can import files with the following extensions. TFW, XML, and AUX XML are required for spatial data references. TIFF files without projection information are not supported.

TFW

Used for plain text files that store X and Y pixel size, rotation information, and world coordinates for a map that is stored as a TIFF image. The extension is a world file and is used to geolocate the raster.

OVR

Used for binary files that store external overview data.

XML

Used for XML-formatted text files that store spatial reference information and metadata in ESRI format.

AUX.XML

Used for XML-formatted text files that store spatial reference information and metadata in the PAM format. Also stores information that is not normally encoded in the header, such as raster statistics, color maps, and pointers to the pyramids file (.rrd).

You can import projected GeoTiff files.

Support for types of raster cells:

Supported	Not Supported
Byte	Unknown data type
Unsigned Int16 (unsigned short)	Complex Int16
Int16 (short)	Complex Int32
Unsigned Int32 (unsigned integer)	Complex Float32
Int32 (integer)	Complex Float64
Float 32
Float 2 (double)

Touchstone supports both built-in overview and separate overview files created by other GIS applications. You can import GeoTIFF files with existing overviews (already built pyramids) or without them. Touchstone will build the overviews for the GeoTIFF source files that come without an overview. However, if you are importing large GeoTIFF files, you should create the pyramids before importing the files. If you import a GeoTIFF file without an overview and its width or height is larger than 32,678 pixels, the import will fail.