The suffixes shown are prefixed by the current <ReaderKeyword> in a mapping file. By default, the <ReaderKeyword> for the DTED reader is DTED.
DATASET
Required/Optional: Required
This is the name of a folder containing one or more DTED files. They normally have an extension like .dt0, .dt1 or .dt2 depending on the DTED level.
Example:
DTED_DATASET D:\DATA\DTED
Workbench Parameter: Source DTED (Digital Terrain Elevation Data) File(s)
IDs
This optional specification is used to limit the available and defined DTED files read. If no IDs are specified, then all available DTED files are read.
The syntax of the IDs keyword is:
<ReaderKeyword>_IDs <baseName1> \ <baseName2> ... \ <baseNameN>
The example below selects only the W118N033.DT1 file for input during a translation:
DTED_IDs W118N033
Workbench Parameter
Feature Types to Read
DEM_SAMPLE
DTED files can produce a lot of point features. A standard level 1 DTED file contains 1201 x 1201, or over 1.4 million features. Sometimes, it is desirable to extract only a subsample of the features, while maintaining a regular grid pattern of points. The DEM_SAMPLE keyword is used to specify a decimation factor that is applied in the horizontal and vertical directions.
A DEM_SAMPLE value of 3, for instance, results in only one in three points in the horizontal and vertical directions being returned from the reader, resulting in an 8/9ths reduction in the total number of features.
Example:
DTED_DEM_SAMPLE 3
Default: 1 (no decimation)
Workbench Parameter: Decimation Factor
AS_DEMRASTER
Required/Optional: Optional
DTED files can be interpreted by FME as a group of associated point features or as a single raster feature. The AS_DEMRASTER keyword is used to specify which way FME will handle the raster. Raster files can be translated much more efficiently as raster features than as many point features.
An AS_DEMRASTER value of no, for instance, results in the handling of elevation values in a raster file as individual point features. A value of yes, conversely, results in the handling of each raster file as a single raster feature.
Example:
DTED_AS_DEMRASTER yes
Value: yes (read as raster) | no (read as points)
Default: yes (read as an FME raster feature)
Workbench Parameter: Read as DEM Raster
GROUP_BY_DATASET
When the value is set to No, the only feature type this reader will use is the reader type name.
When the value is set to Yes, the feature type of each dataset is the filename (without the path or the extension) of the dataset.
Required/Optional
Required
Values
YES | NO (default)
Mapping File Syntax
GROUP_BY_DATASET “Yes”
Workbench Parameter
Feature Type Name(s)
EXPOSED_ATTRS
This directive allows the selection of format attributes to be explicitly added to the reader feature type.
This is similar to exposing format attributes on a reader feature type once it has been generated; however, it is even more powerful because it enables schema-driven applications other than Workbench to access and leverage these attributes as if they were explicitly on the schema as user attributes.
The result of picking a list of attributes is a comma-separated list of attribute names and types that will be added to the schema features. Currently all reader feature types will receive the same set of additional schema attributes for a given instance of the reader.
Required/Optional
Optional
Mapping File Syntax
Not applicable.
While it is possible for FME Objects applications to invoke this directive, the required format is not documented.
This directive is intended for use in our GUI applications (for example, Workbench) only.
Workbench Parameter
Additional Attributes to Expose