Syntax

   FACTORY_DEF <ReaderKeyword> RasterSegmentationFactory
   [FACTORY_NAME <factory name>]
   [INPUT FEATURE_TYPE <factory type>
      [<attribute name> <attribute value>]*
      [<feature function>]*]*
   [POLYGON_MODE (NODATA|UNIQUE)]
   [POLYGON_LABEL_ATTRIBUTE <attribute name>]
   [EXTRACT_NODATA (yes|no)]
   [PRESERVE_ATTRIBUTES (yes|no)]
   [REJECT_INVALID_FEATURES (yes|no)]
   [OUTPUT POLYGONS FEATURE_TYPE <feature type>
      [<attribute name> <attribute value>]*
      [<feature function>]*]*

Overview

   This factory creates polygons from input rasters.

   The POLYGON_MODE option specifies how polygon boundaries are determined. The
   factory supports the NODATA and UNIQUE modes. See the Polygon Mode section
   for more details.

   The POLYGON_LABEL_ATTRIBUTE clause specifies the name of an attribute that
   will be created on every output feature describing the type of the polygon.
   The value of this attribute depends on what mode the factory is in. See the
   Polygon Mode section for more details.

   The PRESERVE_ATTRIBUTES clause specifies whether the output vector features
   should retain attributes from the input raster feature.

   This factory accepts only features that have raster geometry. This factory
   supports sub-selection of raster bands.

   Polygon Mode

   NODATA

   In this mode, the extracted polygons divide the raster into regions of nodata
   and data.

   A cell is considered to be nodata when, for each selected band, the value for
   that cell is equal to that band's nodata value. If any cell value is not
   equal to that band's nodata value, the cell will be considered data.

   The POLYGON_LABEL_ATTRIBUTE value will be set to "data" for polygons
   representing a region of data, and "nodata" for polygons representing a
   region of nodata.

   In this mode, all selected bands are required to have a nodata value.

   UNIQUE

   In this mode, a polygon is created for each contiguous area of pixels with
   the same value. Nodata polygons will only be extracted if EXTRACT_NODATA
   is set to Yes.

   The POLYGON_LABEL_ATTRIBUTE value will be set to a comma-separated list of
   the band values covered by that polygon. For example, the label for a raster
   with three bands might be something like 64,128,255.

   The REJECT_INVALID_FEATURES clause specifies whether the factory will fail
   upon being supplied invalid features or output them to the <REJECTED> port.

Output Tags

   The RasterSegmentationFactory supports the following output tag.

   POLYGONS

      Output polygons created from the input raster(s).

   <REJECTED>

      The output feature that is deemed to be invalid input for any of the
      following reasons:
         - The feature does not have rich geometry
         - The raster does not have any bands
         - The raster has invalid dimensions