Canadian Digital Elevation Data (CDED) Reader/Writer

FME Format Type Identifier

CDED

Reader/Writer

Both

Typical File Extensions

.dem

CDED is a raster format with no provision for storing user-defined attributes for the data.

All CDED information is contained within one file, beginning with a metadata header. The data is stored in profiles, each of which has its own metadata header. A profile is one column in the raster. CDED files typically have a .dem extension.

Two versions of CDED are recognized by FME:

  • the original CDED specifications distributed by CTI, and
  • the CDED-1 specifications distributed by GeoBase.

Note: The CDED format has a fixed coordinate system: LL-83. Any features given to the CDED writer will be reprojected to this coordinate system.

CDED Product and System Requirements

Format

FME Platform

Operating System

Reader/Writer

FME Form

FME Flow

FME Flow Hosted

Windows 64-bit

Linux

Mac

Reader

Yes

Yes

Yes

Yes

Yes

Yes

Writer

Yes

Yes

Yes

Yes

Yes

Yes

Reader Overview

The CDED reader creates FME feature data from a CDED file specified by the reader dataset. FME considers a single CDED file to be a dataset.

The CDED reader will read both CDED and CDED-1 files.

Writer Overview

The CDED writer creates and writes feature data to a CDED folder specified by writer dataset.

The writer writes either CDED or CDED-1 files, as specified by the CDED Version writer parameter.

The names of the CDED output files written to the output dataset folder are determined from the FME Feature Type. The folder need not exist before the translation occurs.

Any old CDED files in the folder with the same name are overwritten with the new feature data. The CDED writer distinguishes duplicate output files by appending numbers to the filenames. Please see About Feature Attributes for details.

FME Raster Features

FME raster features represent raster data and use several concepts that are unlike those used in the handling of vector data.

For comprehensive information about how FME processes raster data, see Rasters.

CDED only supports rasters with a single numeric band.