GeoTIFF Reader Parameters

Feature Type Name

This parameter allows you to choose different naming schemes for a feature type, and the number of feature types generated for the reader.

The Feature Type Name changes, depending on the selection.

Value	Feature Type Name	Example
From Format Name	<reader_type_name>	FORMAT_NAME
From File Name	<filename>	file
From Subdataset Name	<subdataset_name>	subdataset
From File Name and Subdataset Name	<filename_subdataset_name>	file_subdataset

Note: Some formats have an option for Scientific Dataset Name in place of the Subdataset Name. Examples for these formats are shown in the following table:

Value	Feature Type Name	Example
From Format Name	<format_name>	HDF4_ASTER
From File Name	<filename>	CURRENT_DHW
From Scientific Dataset Name	<scientific_dataset_name>	[331X720]_ SURFACE_FLAG__8_BIT_UNSIGNED_ INTEGER
From File Name and Scientific Dataset Name	<filename_scientific_dataset_name>	CURRENT_DHW_ [331X720]_ SURFACE_FLAG__8_BIT_UNSIGNED_ INTEGER

Apply GCPs

By default, the GCP information is preserved as properties on the raster geometry.

If you select this checkbox, the GCP information, including a GCP projection, will be read from the file and applied to the raster data as an affine transformation.

Nearest Neighbor

Applies a projection based on the value of the pixel closest to the GCP. This method is the least resource-intensive, but also produces the lowest resolution GCP.

Bilinear

Applies a projection by averaging the closest 2x2 neighborhood of pixel values surrounding the GCP. This method produces higher-quality results than Nearest Neighbor.

Bicubic

Applies a projection by applying a weighted average of the closest 4x4 neighborhood of pixel values surrounding the GCP, with closer pixels weighted higher than farther pixels. Bicubic interpolation requires the most amount of processing time.

Additional Attributes to Expose

Use this parameter to expose Format Attributes in Workbench when you create a workspace:

In a dynamic scenario, it means these attributes can be passed to the output dataset at runtime.
In a non-dynamic scenario where you have multiple feature types, it is convenient to expose additional attributes using this one parameter. For example, if you have ten feature types and want to expose the same attribute in each one, it is easier to define it once than it is to set each feature type individually in the workspace.

Use 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 intersect with the bounding box are returned.

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

Clip to Search Envelope

When selected, this parameter removes any portions of imported features being read that are outside the Search Envelope.

The example below illustrates the results of the Search Envelope when Clip to Search Envelope is not selected (set to No) and when it is selected (set to Yes).

No: Any features that cross the search envelope boundary will be read, including the portion that lies outside of the boundary.
Yes: Any features that cross the search envelope boundary will be clipped at the boundary, and only the portion that lies inside the boundary will be read. The underlying function for the Clip to Search Envelope function is an intersection; however, when Clip to Search Envelope is selected, a clipping operation is also performed in addition to the intersection.

Pyramid Level to Read

When a GeoTIFF file contains pyramids (reduced-resolution images), this parameter specifies the pyramid level to read.

Pyramid level 0 represents the original raster data. Values greater than 0 represent a reduced-resolution image.

Note that the GeoTIFF format does not guarantee that the levels are ordered. For example, pyramid level 2 may have more rows or columns than pyramid level 1, or vice versa.

Prefer File Coordinate System Units

When the value is set to Yes and the ProjLinearUnitsInterpCorrectGeoKey flag is present in the file, the coordinate system offsets will be assumed to be in the linear units of the projection.
When the value is set to No or the ProjLinearUnitsInterpCorrectGeoKey flag is not present, the Offsets in Coordinate System Units parameter is used to determine the interpretation of the coordinate system offsets.

Offsets in Coordinate System Units

Yes: The coordinate system offsets stored in the GeoTIFF file will be interpreted as being in the linear units of the projection; this is correct according to the GeoTIFF specification.
No: The coordinate system offsets will be interpreted as being in meters; this is what is actually done in practice by many software packages.

Note: If the offsets are explicitly marked as being in the coordinate system units (via the ProjLinearUnitsInterpCorrectGeoKey flag in the GeoTIFF dataset), and Prefer File Coordinate System Units is set to Yes, this option is ignored.

Ignore Raster Type Key

GeoTIFF contains a “raster type” key which specifies whether each pixel in the file represents an area (“PixelIsArea”) or a point (“PixelIsPoint”).

When reading PixelIsPoint data, by default, the raster extents is shifted up and left by half a pixel when transformed to the FME georeferencing model. Setting this value to Yes prevents this adjustment from happening.

GeoTIFF Reader Parameters

Dataset Parameters

GCP Interpolation Method

Schema Attributes

Advanced