Canadian Digital Elevation Data (CDED) Feature Representation
In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Type Attributes), this format also adds format-specific attributes (Format Attributes).
CDED raster features are specified by a matrix of x, y, and z coordinates. If known, the coordinate system will be specified.
All CDED features contain a cded_type attribute, which identifies the geometric type.
Attribute Name |
Contents |
---|---|
cded_type |
The CDED geometric type of this entity. This is always cded_raster. |
cded_file_name |
This is a string that specifies the basename of the raster file. |
cded_producer |
This is a string that specifies the producer of the data. |
cded_process_code |
This is a one-byte integer that specifies how to the data is processed. Range: 1...8 Default: 8 |
cded_origin_code |
This is a 4-character string that specifies the mapping origin. |
cded_level_code |
This is an integer defining the DEM level. This field is always set to 1 for 1:50,000 and 1:250,000 CDED. Range: 1-3 Default: 1 |
cded_code_defining_elevation_pattern |
This is an integer specifying the regularity of the elevation pattern. Range: regular|random Default: regular |
cded_spatial_ |
A positive real number used to specify a scale to apply to the elevation values in the z dimension. In USGS DEM data, this is stored as spatial_resolution_z. When specified for the writer, elevation values will be scaled appropriately. This value is tied to the value of cded_units; resolutions of 1 decimal place for feet and 2 decimal places for meters are permitted. Default: 1 |
cded_accuracy_code_for_elevations |
A number that specifies the existence of accuracy information for this dataset. 0 indicates unknown accuracy information. Range: 0|1 Default: 0 |
cded_units |
The unit of measure for the z coordinate (the altitude). Range: meters|feet Default: No default |
cded_suspect_and_void_area_flag |
This is a one-digit integer that indicates if the data contains void areas. Only valid for CDED-1. Range: 0|2 Default: Calculated based on percent void |
cded_data_edition |
This is a four-digit integer specifying the data edition or version used. The first two digits indicate the data edition while the last two digits indicate the specifications version. Only valid for CDED-1. Range: 0...9999 Default: 1021 |
cded_percent_void |
This is an integer equal to the percentage of nodes in the file set to void (-32767). This is only populated if the cded_data_edition field indicates a void. Only valid for CDED-1. Range: 0...100 Default: Calculated based on number of void nodes |