Decodes a binary attribute containing encoded rasters stored as Blobs, replacing the feature’s geometry with the decoded raster.

Jump to Configuration

Typical Uses

  • Restoring rasters previously extracted into an attribute by the RasterExtractor, often used to store rasters as Blobs in non-spatial databases.
  • Creating geometry from rasters read with an AttributeFileReader transformer.
  • Extracting images (such as photos) stored as Blobs on a feature.

How does it work?

The RasterReplacer receives features of any geometry type (or no geometry) that have rasters stored as Blob attribute of the feature, most often a result of having previously used the RasterExtractor to store them as Blob attributes to meet format or processing requirements.

The format of the encoded Blob raster must be provided. The attribute storing the Blob may be optionally removed after decoding and replacing the feature’s geometry with the raster. Removing the attribute reduces feature size and memory usage, and may improve performance.

Raster band and palette selection are not applicable to this transformer.


Usage Notes

  • This transformer only works with raster formats. Use the GeometryReplacer for vector formats or the PointCloudReplacer for point cloud formats.
  • Different encoding formats may carry through different information. For example, GeoTIFF preserves coordinate system and extents, whereas PNG does not.

Choosing a Raster Transformer

FME has an extensive selection of transformers for working with raster data. They can be generally categorized as working with whole rasters, bands, cells or palettes, and those designed for workflow control or combining raster with vector data.

For information on raster geometry and properties, see Rasters (IFMERaster).


Input Ports

Output Ports


Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters. There are a number of tools and shortcuts that can assist in constructing values, generally available from the drop-down context menu adjacent to the value field.

Dialog Options - Tables

Transformers with table-style parameters have additional tools for populating and manipulating values.


Processing Behavior


Feature Holding


Dependencies None

FME Community

The FME Community is the place for demos, how-tos, articles, FAQs, and more. Get answers to your questions, learn from other users, and suggest, vote, and comment on new features.

Search for all results about the RasterReplacer on the FME Community.


Examples may contain information licensed under the Open Government Licence – Vancouver and/or the Open Government Licence – Canada.