RasterTiler

	Tiler	RasterTiler
Tiling extents	Cumulative over all features	Single feature
Type of data accepted	All types except surfaces and solids	Raster only
Tile size units	Ground coordinates	Pixel coordinates
Tile row numbering (0, 1,...)	Selectable	Top to bottom
Supports forcing equal-size tiles	No	Yes
Supports raster index attribute	No	Yes
Supports number of horizontal/vertical tiles attribute	No	Yes

Example: Tiling a raster by tile size

In this example, we will tile a single orthophoto, by Tile Size. Note that the original image is 1600 by 1000 pixels.

The raster is routed into a RasterTiler.

In the parameters dialog, we choose Tile Size, and set the size to 400 by 400 cells (pixels).

This will produce four tiles across, exactly divided into the original 1600 pixels in width. It will produce three tiles vertically, but the lowest row will be partial (400 does not divide into 1000 equally). By turning on Force Equal Sized Tiles (Yes), the lowest row will be padded to produce full size tiles.

Twelve tiles are output, as shown here with their extents overlaid in pink. Note the new attributes which indicate the source raster, the number of rows and columns produced by the tiling operation, and this raster’s position. Row and column counts start from zero (0).

The lowest row has been padded with empty cells to match the defined tile size.

Example: Tiling a raster by number of tiles

In this example, we will tile a single orthophoto, using Number of Tiles. Note that the original image is 1600 by 1000 pixels.

The raster is routed into a RasterTiler.

In the parameters dialog, we choose Number of Tiles and set both the horizontal and vertical number to 3.

Nine tiles are output, shown here with their extents overlaid in yellow. The tile size is determined by dividing the dimensions of the original raster by the defined number of horizontal and vertical tiles.

When the division of number of tiles into the dimension produces partial cells/pixels, the number will be rounded up. In this case, 1600 width divided by 3 tiles = 533.33. The tiles are created as 534, 534, 532. If we had turned on Force Equal Sized Tiles, two columns of blank cells would be padded on the right-hand tiles.

Note the new attributes which indicate the source raster, the number of rows and columns produced by the tiling operation, and this raster’s position. Row and column counts start from zero (0).

Raster Transformers

Working with Rasters

These transformers generally apply to whole rasters.

RasterCellOriginSetter	Sets the cell origin point within cells in a raster.
RasterConvolver	Applies a convolution filter (sometimes called a kernel or lens) to raster features and outputs the results.
RasterExpressionEvaluator	Evaluates expressions on each cell in a raster or pair of rasters, including algebraic operations and conditional statements.
RasterExtentsCoercer	Replaces the geometry of input raster features with a polygon covering either the extents of a raster or the extent of data within a raster.
RasterGCPExtractor	Extracts Ground Control Point (GCP) coordinate system and point values from a raster feature and exposes them as attributes.
RasterGCPSetter	Sets Ground Control Points (GCPs) on a raster, pairing cell positions with known coordinates.
RasterGeoreferencer	Georeferences a raster by either known corner coordinates or origin, cell size, and rotation.
RasterHillshader	Generates a grayscale shaded relief representation of terrain, based on elevation values.
RasterInterpretationCoercer	Alters the interpretation type of rasters, including all bands, and converts cell values if necessary.
RasterMosaicker	Merges multiple raster features into a single raster feature.
RasterPropertyExtractor	Extracts the geometry properties of a raster feature and exposes them as attributes.
RasterPyramider	Resamples rasters to multiple resolutions, based on either number of levels or dimensions of the smallest output raster.
RasterRegisterer	Transforms an image to minimize its difference with another.
RasterResampler	Resamples rasters, based on specified output dimensions, cell size in ground units, or percentage of original, and interpolates new cell values.
RasterRotationApplier	Rotates a raster feature according to its rotation angle property, interpolating new cell values, updating all other affected raster properties, and producing an output raster feature with a rotation angle of zero.
RasterSharpener	Enhances the features of a raster image. The RasterSharpener enhances the borders, lines, and curves while reducing noise in the flat areas of the raster image.
RasterSubsetter	Clips raster features using pixel bounds instead of ground coordinates, and optionally adds cells around the perimeter.
RasterTiler	Splits each input raster into a series of tiles by specifying either a tile size in cells/pixels or the number of tiles.
RasterToPolygonCoercer	Creates polygons from input raster features. One polygon is output for each contiguous area of pixels with the same value in the input raster.
WebMapTiler	Creates a series of image tiles that can be utilized by web mapping applications such as Bing™ Maps, Google Maps™, or Web Map Tile Service. This is done by resampling rasters to various different resolutions and then splitting them into tiles.

Working with Bands

These transformers generally apply to bands.

RasterBandAdder	Adds a new band to a raster feature.
RasterBandCombiner	Merges coincidental raster features into a single output raster feature, preserving and appending all bands.
RasterBandInterpretationCoercer	Alters the interpretation type of individual raster bands, converting cell values if necessary.
RasterBandKeeper	Removes all unselected bands from a raster feature.
RasterBandMinMaxExtractor	Extracts the minimum and maximum band values, palette keys, and palette values from a raster feature, and adds them to a list attribute.
RasterBandNameSetter	Sets the band name of selected bands on a raster, making raster contents simpler to understand compared to band numbers.
RasterBandNodataRemover	Removes the existing Nodata identifier from selected bands of a raster feature. Any values previously equal to the Nodata value are considered valid data.
RasterBandNodataSetter	Sets a new Nodata value on selected bands of a raster feature.
RasterBandOrderer	Specifies the required order of bands in a raster. Bands are reordered according to the input band indices.
RasterBandPropertyExtractor	Extracts the band and palette properties of a raster feature and exposes them as attributes.
RasterBandRemover	Removes any selected bands from a raster feature.
RasterBandSeparator	Separates bands or unique band and palette combinations, and outputs either individual raster features or a single new raster feature containing all combinations.
RasterStatisticsCalculator	Calculates statistics on raster bands and adds the results as attributes.

Working with Cells

These transformers generally apply to individual cells.

RasterAspectCalculator	Calculates the aspect (direction of slope) for each cell of a raster. Aspect is measured in degrees from 0 to 360, clockwise from north.
RasterCellCoercer	Creates individual points or polygons for each cell in a raster, optionally extracting band values as z coordinates or attributes.
RasterCellValueCalculator	Evaluates basic arithmetic , minimum, maximum or average operations on the cell values of a pair of rasters.
RasterCellValueReplacer	Replaces a range of band values in a raster with a new single value.
RasterCellValueRounder	Rounds off raster cell values.
RasterSegmenter	Partitions a raster image into arbitrarily sized groups of cells from the input image based on intensity differences in the input raster image cells.
RasterSingularCellValueCalculator	Performs basic arithmetic operations on the cell values of a raster against a numeric value.
RasterSlopeCalculator	Calculates the slope (maximum rate of change in z) for each cell of a raster.

Working with Palettes

These transformers generally apply to palettes.

RasterPaletteAdder	Creates a palette from an attribute, and adds this palette to all selected bands on a raster.
RasterPaletteExtractor	Creates a string representation of an existing palette on a raster and saves it to an attribute.
RasterPaletteGenerator	Generates a palette out of the selected band(s) of a raster. The output raster will have the selected band(s) replaced by a new band with a palette.
RasterPaletteInterpretationCoercer	Alters the interpretation type of raster palettes.
RasterPaletteNodataSetter	Identifies the palette key that matches a raster band’s Nodata value, and sets a value on it.
RasterPaletteRemover	Removes selected palette(s) from raster features.
RasterPaletteResolver	Resolves the palette(s) on a raster by replacing cell values with their corresponding palette values. Palette values with multiple components, such as RGB, are broken down and the individual values assigned to multiple, newly-added bands.

Workflow Control

These transformers generally control the flow of features in a workspace.

RasterCheckpointer	Forces accumulated raster operations to be processed, saving the state to disk and releasing resources to tune performance or assist with memory limitations.
RasterConsumer	Reads raster features for testing purposes, including any accumulated raster operations. No additional operations are performed, and nothing is done with the features.
RasterExtractor	Serializes the geometry of a raster feature into a Blob attribute, encoding the contents according to a choice of common binary raster formats.
RasterNumericCreator	Creates a numeric raster of specified size and resolution, with default cell values.
RasterReplacer	Decodes a binary attribute containing encoded rasters stored as Blobs, replacing the feature’s geometry with the decoded raster.
RasterRGBCreator	Creates a color raster feature of specified size, resolution, and interpretation type, with default cell values.
RasterSelector	Selects specific bands and palettes of a raster for subsequent transformer operations.

Vectors and Rasters

These transformers generally involve using rasters and vector data together.

ImageRasterizer	Creates a raster representation of vector or point cloud input features, using the fme_color attribute over a solid background fill for vector features. Point clouds may be rendered using their color or intensity components.
NumericRasterizer	Creates a numeric raster representation of vector or point cloud input features, where cell values are taken from the z coordinates of the input features and overlaid on a uniform background.
MapnikRasterizer	Generates a raster from input vector and raster features, with fine control over symbolization and labeling, using the Mapnik toolkit.
PointCloudOnRasterComponentSetter	Sets point cloud component values by overlaying a point cloud on a raster. The component values for each point are interpolated from band values at the point location.
PointOnRasterValueExtractor	Extracts the band and palette values from a raster at the location of one or more input points and sets them as attributes on the feature.
RasterDEMGenerator	Produces a raster digital elevation model (DEM) by uniformly sampling a Delaunay triangulation generated from input points and breaklines.
VectorOnRasterOverlayer	Rasterizes vector or point cloud features onto an existing raster. For vector features the fme_color attribute sets pixel color, and point clouds may be rendered using their color or intensity components.

Rectangle Transformers Comparison

Transformer	Function
Creator	Creates one or more new features with box geometry of a specific size and position (when Geometry Object is Box).
2DBoxReplacer	Replaces an existing feature’s geometry with a box of a specific size and position.
BoundingBoxAccumulator	Creates one rectangle that encompasses all features received.
BoundingBoxReplacer	Individually replaces the geometry of each feature with a rectangle that covers its extents.
RasterExtentsCoercer	Individually replaces the geometry of each raster feature with a rectangle that covers its extents (with various Extents Type options).
BoundsExtractor	Extracts the coordinate values that describe an individual feature’s bounding box (or cube) and stores them as attributes.
2DGridAccumulator	Creates a series of regularly-spaced rectangles that span the extent of all features received (when Type of Grid to Create is Polygons).
2DGridCreator	Creates a series of regularly-spaced rectangles of a specific size and position (when Type of Grid to Create is Polygons).
Tiler and RasterTiler	Do not create actual rectangles, but chop features into a series of rectangular tiles, specified in a similar fashion to the 2DGridAccumulator.

Input

This transformer accepts only raster features.

Tiles

The tiles produced according to the parameter selections.

Non-raster features will be routed to the <Rejected> port, as well as invalid rasters.

Rejected features will have an fme_rejection_code attribute with one of the following values:

INVALID_GEOMETRY_TYPE

INVALID_RASTER_NO_BANDS

INVALID_GEOMETRY_DEGENERATE

INVALID_PARAMETER_NUMBER_OF_ROWS

INVALID_PARAMETER_NUMBER_OF_COLUMNS

INVALID_PARAMETER_SEED_ROW

INVALID_PARAMETER_SEED_COLUMN

INVALID_PARAMETER_NUMBER_OF_HORIZONTAL_TILES

INVALID_PARAMETER_NUMBER_OF_VERTICAL_TILES

Rejected Feature Handling: can be set to either terminate the translation or continue running when it encounters a rejected feature. This setting is available both as a default FME option and as a workspace parameter.

Tile Size

Tile Size or Number of Tiles	Choose how the input raster should be split: Tile Size: define the size in vertical and horizontal number of pixels Number of Tiles: Divide the raster into a fixed number of tiles
Number of Columns (cells)	If tiling by Tile Size, the number of cells (pixels) to include in each tile horizontally. Must be greater than 0.
Number of Rows (cells)	If tiling by Tile Size, the number of cells (pixels) to include in each tile vertically. Must be greater than 0.
Seed Column	If tiling by Tile Size, specify the starting location to start tiling. Default is (0,0) - (Seed Column, Seed Row) - which is the upper-left corner of the raster.
Seed Row	If tiling by Tile Size, specify the starting location to start tiling. Default is (0,0) - (Seed Column, Seed Row) - which is the upper-left corner of the raster.
Number of Horizontal Tiles	If tiling by Number of Tiles, the desired number of tiles to be created horizontally. Must be an integer greater than 0.
Number of Vertical Tiles	If tiling by Number of Tiles, the desired number of tiles to be created vertically. Must be an integer greater than 0.
Equal Sized Tiles	Controls behavior when the raster size is not a multiple of the requested tile size or number of tiles. No: Tiles on the right or bottom edge of the raster may be smaller than other tiles. Yes: All tiles will be the same size. Tile extents that exceed the raster will be padded with the Nodata value if one is set on the band; if no Nodata value is set, RGB rasters will have an alpha band added to identify the padding regions.

Output Attribute Names

Raster Index	Name the attribute to be added to each output tile that identifies which raster it was created from. This index is zero-based, so all tiles created from the first input raster will have a value of 0, all tiles created from the second input raster will have a value of 1, and so on.
Tile Column	Name the attribute to be added to each output tile that identifies that tile’s column position, starting from 0. Tile Column 0, Tile Row 0 corresponds to the upper-left tile.
Tile Row	Name the attribute to be added to each output tile that identifies that tile’s row position, starting from 0. Tile Column 0, Tile Row 0 corresponds to the upper-left tile.
Number of Horizontal Tiles	Name the attribute to be added to each output tile that records the total number of tiles produced horizontally by the tiling operation on the input raster.
Number of Vertical Tiles	Name the attribute to be added to each output tile that records the total number of tiles produced vertically by the tiling operation on the input raster.

How to Set Parameter Values

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.

Using the Text Editor

The Text Editor provides a convenient way to construct text strings (including regular expressions) from various data sources, such as attributes, parameters, and constants, where the result is used directly inside a parameter.

Text Editor

Using the Arithmetic Editor

The Arithmetic Editor provides a convenient way to construct math expressions from various data sources, such as attributes, parameters, and feature functions, where the result is used directly inside a parameter.

Arithmetic Editor

Conditional Values

Set values depending on one or more test conditions that either pass or fail.

Parameter Condition Definition Dialog

Content

Expressions and strings can include a number of functions, characters, parameters, and more.

When setting values - whether entered directly in a parameter or constructed using one of the editors - strings and expressions containing String, Math, Date/Time or FME Feature Functions will have those functions evaluated. Therefore, the names of these functions (in the form @<function_name>) should not be used as literal string values.

Content Types

String Functions	These functions manipulate and format strings.
Special Characters	A set of control characters is available in the Text Editor.
Math Functions	Math functions are available in both editors.
Date/Time Functions	Date and time functions are available in the Text Editor.
Math Operators	These operators are available in the Arithmetic Editor.
FME Feature Functions	These return primarily feature-specific values.
FME Parameters	FME and workspace-specific parameters may be used.
Creating and Modifying User Parameters	Create your own editable parameters.

Dialog Options - Tables

Table Tools

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

Row Reordering

Enabled once you have clicked on a row item. Choices include:

Add a row
Remove a row
Move current row up one
Move current row down one
Move current row to top
Move current row to bottom

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:

Cut a row - delete and copy to clipboard
Copy a row to the clipboard
Paste a row from the clipboard

Cut, copy, and paste may be used within a transformer, or between transformers.

Filter

Start typing a string, and the matrix will only display rows matching those characters. Searches all columns. This only affects the display of attributes within the transformer - it does not alter which attributes are output.

Import

Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers.

Reset/Refresh

Generally resets the table to its initial state, and may provide additional options to remove invalid entries. Behavior varies between transformers.

Note: Not all tools are available in all transformers.

Processing Behavior	Feature-Based
Feature Holding	No
Dependencies	None
Aliases
History

RasterTiler

Typical Uses

How does it work?

RasterTiler or Tiler?

Examples

Usage Notes

Choosing a Raster Transformer

Creating Boxes and Rectangles

Configuration

Input Ports

Output Ports

Parameters

Editing Transformer Parameters

Reference

FME Community