Reader Directives

The directives processed by the ERS reader are listed below. The suffixes shown are prefixed by the current <ReaderKeyword> in a mapping file. By default, the <ReaderKeyword> for the ERS reader is ERS.

DATASET

Required/Optional: Required

The value for this directive is the name of a single ERS file. The usual extension for the file is .ers.

An example of the DATASET directive in use is:

ERS_DATASET “C:\DATA\ERS\san-diego.ers”

Workbench Parameter: Source ER Mapper ERS File(s)

APPLY_GCPS

Required/Optional: Required

The value for this keyword is either YES or NO. If set to YES, GCP information, including a GCP projection, will be read from the file and applied to the raster data as an affine transformation. If set to NO, the GCP information is preserved as properties on the raster geometry.

Default value: NO

Example:

APPLY_GCPS “YES”

Workbench Parameter: Apply GCPs

GCP_INTERPOLATION_METHOD

Required/Optional: Required

The value for this keyword is one of NearestNeighbor, Bilinear or Bicubic. If APPLY_GCPS is set to Yes, this directive must be specified.

Default value: NearestNeighbor

Example:

GCP_INTERPOLATION_METHOD “Bilinear”

Workbench Parameter: GCP Interpolation Method

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)

SEARCH_ENVELOPE

Using the minimum and maximum x and y parameters, define a bounding box that will be used to filter the input features. Only features that interact with the bounding box are returned.

If all four coordinates of the search envelope are specified as 0, the search envelope will be disabled.

Mapping File Syntax

<ReaderKeyword>_SEARCH_ENVELOPE <minX> <minY> <maxX> <maxY>

Note: If all four coordinates of the search envelope are specified as zero, the search envelope will be disabled.

Required/Optional

Optional

Workbench Parameter

Minimum X, Minimum Y, Maximum X, Maximum Y

SEARCH_ENVELOPE_COORDINATE_SYSTEM

This directive specifies the coordinate system of the search envelope if it is different than the coordinate system of the data.

The COORDINATE_SYSTEM directive, which specifies the coordinate system associated with the data to be read, must always be set if the SEARCH_ENVELOPE_COORDINATE_SYSTEM directive is set.

If this directive is set, the minimum and maximum points of the search envelope are reprojected from the SEARCH_ENVELOPE_COORDINATE_SYSTEM to the reader COORDINATE_SYSTEM prior to applying the envelope.

Required/Optional

Optional

Mapping File Syntax

<ReaderKeyword>_SEARCH_ENVELOPE_COORDINATE_SYSTEM <coordinate system>

Workbench Parameter

Search Envelope Coordinate System

CLIP_TO_ENVELOPE

This directive specifies whether or not FME should clip features to the envelope specified in the SEARCH_ENVELOPE directive.

Values

YES | NO (default)

Mapping File Syntax

<ReaderKeyword>_CLIP_TO_ENVELOPE [yes | no]

Workbench Parameter

Clip To Envelope

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