Forces accumulated raster operations to be processed, saving the state to disk and releasing resources to tune performance or assist with memory limitations.

Jump to Configuration

Typical Uses

  • Working around memory limitations in raster processing.
  • Performance tuning by forcing raster processing at specific points in a workspace.

How does it work?

The RasterCheckpointer receives raster features and forces the processing of any accumulated raster processing operations, then writes a temporary file to disk of the features’ current state, freeing up memory.

FME handles rasters in a “delayed evaluation” model. A raster reader reads essential information about a raster, but does not read the actual cell contents until it is absolutely necessary. Transformer operations are accumulated until the results are needed, often being held until the features enter a writer. At that point, the required data is fully read and processed.

This is intended to optimize performance - for example, if a raster is both clipped and reprojected, FME will optimize processing by not reprojecting data that falls outside of the clip boundary and is ultimately discarded.

The RasterCheckpointer forces the raster to be fully read (if required) and accumulated operations to be processed immediately, saves the state to disk, and releases the resources that were in use.

RasterCheckpointers are generally not necessary in raster processing workspaces, as data is stored in memory. However, when memory limitations are a factor, such as very large datasets, using the RasterCheckpointer to save the state before performing more operations may lead to performance improvements.

This transformer is unaffected by raster band and palette selection.


Usage Notes

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


This transformer has no parameters.

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 RasterCheckpointer on the FME Community.


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