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ImageRasterizer

Draws input point, line and polygon features onto a color raster filled with the background color. The fme_color attribute of the input vector features is used to generate pixel values. Features without an fme_color attribute will be discarded.

Input Ports

ClosedInput

The Input port takes the vector features that will be rasterized. These features are valid only if they have an fme_color attribute.

Output Ports

ClosedRaster

The raster drawn from a group of features.

Parameters

ClosedGroup By

If the Group By parameter is set to an attribute list, one raster per group will be produced.

ClosedParallel Processing

Note: How parallel processing works with FME: see About Parallel Processing for detailed information.

This parameter determines whether or not the transformer should perform the work across parallel processes. If it is enabled, a process will be launched for each group specified by the Group By parameter.

Parallel Processing Levels

Parameter Number of Processes
No Parallelism 1
Minimal coresThe processor, or CPU, is the physical part of the computer that performs mathematical calculations. It is the most important part of a computer system. Traditional processors have only one core on the processor, meaning that at any given time, only one set of calculations is being performed. If a processor is dual-core, this means the single chip contains hardware for two processors, now called cores to distinguish them from the single chip, running simultaneously, side by side. (Source: http://www.ehow.com/facts_5730257_computer-core-processors_.html) / 2
Moderate exact number of cores
Aggressive cores x 1.5
Extreme cores x 2

For example, on a quad-core machine, minimal parallelism will result in two simultaneous FME processes. Extreme parallelism on an 8-core machine would result in 16 simultaneous processes.

You can experiment with this feature and view the information in the Windows Task Manager and the Workbench Log window.

ClosedInput Ordered

No: This is the default behavior. Processing will only occur in this transformer once all input is present.

By Group: This transformer will process input groups in order. Changes on the value of the Group By parameter on the input stream will trigger batch processing on the currently accumulating group. This will improve overall speed if groups are large/complex, but could cause undesired behavior if input groups are not truly ordered.

Raster Properties

ClosedSize Specification, Number of Columns (cells), Number of Rows (cells), X Cell Spacing, Y Cell Spacing

To set the size of the output raster, specify either the dimensions or the cell size.

To set the output raster size using dimensions, set the Size Specification to RowsColumns and specify values for both the Number of Columns and Number of Rows.

To set the output raster size using cell size, set the Size Specification to CellSize and specify values for both the X Cell Spacing and Y Cell Spacing.

Interpretation

ClosedInterpretation Type

This parameter sets the interpretation of the output raster.

Pixel values for red, green, and blue bands will be taken from the corresponding component of a feature's fme_color attribute. Pixel values for gray bands will be the average of the fme_color components.

ClosedAlpha Value

This parameter sets pixel values for alpha bands.

Background

ClosedBackground Color

The Background Color parameter sets the background color for red, green, blue, or gray bands.

Click the colored square to the right of the text field, or edit the contents of the field directly. The color must be specified as <red>,<green>,<blue> where each of <red>, <green>, and <blue> is a number between 0 and 1.

ClosedBackground Alpha Value

The Background Alpha Value parameter sets the background value for any alpha bands on the raster. It must also be a number between 0 and 1.

ClosedFill Background with Nodata

If the Fill Background with Nodata parameter is Yes, the background color will also be flagged as the nodata value for each raster band.

Anti-Aliasing

ClosedAnti-Aliasing

If the Anti-Aliasing parameter is Yes, the output lines will be smoothed using an anti-aliasing algorithm.

ClosedTolerance

The Tolerance parameter is the maximum normalized distance from a line segment or polygon vertex to a pixel to be rendered. For example a tolerance of 1.0 will draw all pixels touched by the input vector line, while a tolerance of 0.0 will draw only those pixels where the input vector line passes directly through their center. Tolerance can only be selected when anti-aliasing is off.

Ground Extents

ClosedGround Extents

If the Ground Extents parameter is set to Use input data ground extents, which means the extents are not explicitly specified, the output raster extents will be determined by the union of the bounding boxes of the valid input vector features. If the Ground Extents parameter is set to Specify ground extents, the remaining Ground Extents parameters are used to specify the extents of the output raster.

Note: Note: The raster extent is absolute, measured from the outer edges of the border row and column pixels.

ClosedMinimum X

This specifies the minimum x value of the output raster. It is used when the Ground Extents parameter is set to Specify ground extents.

ClosedMinimum Y

This specifies the minimum y value of the output raster. It is used when the Ground Extents parameter is set to Specify ground extents.

ClosedMaximum X

This specifies the maximum x value of the output raster. It is used when the Ground Extents parameter is set to Specify ground extents.

ClosedMaximum Y

This specifies the maximum y value of the output raster. It is used when the Ground Extents parameter is set to Specify ground extents.

Point Cloud

ClosedInput Component

When drawing point clouds on color bands, the Input Component specifies which component of the point should be used to set the color of the raster pixel. If the parameter is set to Color, the points in the cloud must have a color component. If the parameter is set to Intensity, the points in the cloud must have an intensity component. The intensity component is converted to a color using a grayscale continuum, where the minimum intensity in the cloud is black and the maximum intensity in the cloud is white.

Related Transformers

This transformer is intended for producing color images. For producing elevation rasters, use the NumericRasterizer instead.

To overlay vector features onto an existing raster, use the VectorOnRasterOverlayer instead.

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.

Transformer Categories

Cartography and Reports

Rasters

FME Licensing Level

FME Professional edition and above

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Tags Keywords: minimum bounding rectangle MBR fme_colour rasteriser Rasterizer pointcloud