Syntax

   FACTORY_DEF <ReaderKeyword> RasterSubsetFactory
   [FACTORY_NAME <factory name>]
   [INPUT FEATURE_TYPE <factory type>
      [<attribute name> <attribute value>]*
      [<feature function>]*]*
   [NUM_TILE_ROWS <number of rows in each tile>]
   [NUM_TILE_COLUMNS <number of columns in each tile>]
   [SEED_ROW <row with which tile boundaries align>]
   [SEED_COLUMN <column with which tile boundaries align>]
   [NUM_HORIZONTAL_TILES <number of horizontal tiles>]
   [NUM_VERTICAL_TILES <number of vertical tiles>]
   [FORCE_EQUAL_SIZED_TILES (yes|no)]
   [RASTER_INDEX_ATTRIBUTE <attribute name>]
   [TILE_ROW_ATTRIBUTE <attribute name>]
   [TILE_COLUMN_ATTRIBUTE <attribute name>]
   [NUM_HORIZONTAL_TILES_ATTRIBUTE <attribute name>]
   [NUM_VERTICAL_TILES_ATTRIBUTE <attribute name>]
   [REJECT_INVALID_GEOM <yes|no>]
   [OUTPUT TILES FEATURE_TYPE <feature type>
      [<attribute name> <attribute value>]*
      [<feature function>]*]*
   [OUTPUT REJECTED FEATURE_TYPE <feature type>
      [<attribute name> <attribute value>]*
      [<feature function>]*]*

Overview

   This factory splits each input raster feature into a series of tiles. The 
   input raster can be split up by specifying either a tile size or a number of 
   tiles.

   The NUM_TILE_ROWS and NUM_TILE_COLUMNS clauses specify the tile size. These 
   values must be greater than 0.

   The SEED_ROW and SEED_COLUMN parameters specify a "seed" location from which 
   tiling will start. That is, tile boundaries will align with the specified 
   location. By default this is (0,0), meaning tiling starts from the upper-left 
   corner of the raster.

   The NUM_HORIZONTAL_TILES and NUM_VERTICAL_TILES clauses specify the number of 
   tiles into which the input rasters will be split. These values must be 
   greater than 0.

   The FORCE_EQUAL_SIZED_TILES option controls behavior when the raster size is 
   not a multiple of the requested tile size or number of tiles. When this is 
   set to NO, tiles on the right or bottom edge of the raster may be smaller 
   than other tiles. When this is set to YES, all tiles will be the same size. 
   Tiles that go off the edge of 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. For example, suppose you 
   have a raster of size 1000 columns and a selected column tile size of 256. 
   When the FORCE_EQUAL_SIZED_TILES option is NO, three tiles of 256 columns and 
   one tile of 232 columns will be generated. When this option is YES, four 
   tiles of 256 columns will be generated, where the last tile contains 24 
   columns of padding.

   If the RASTER_INDEX_ATTRIBUTE clause is specified, an attribute will 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, etc.

   If the TILE_ROW_ATTRIBUTE and TILE_COLUMN_ATTRIBUTE clauses are specified, 
   attributes will be added to each output tile that identify the position of 
   that tile in the input raster. These indices are zero-based. Tile row 0, tile 
   column 0 corresponds to the upper-left tile.

   If the NUM_HORIZONTAL_TILES and NUM_VERTICAL_TILES clauses are specified, 
   attributes will be added to each output tile that identify the number of 
   horizontal and vertical tiles in the input raster.

   This factory accepts only features that have raster geometry and is 
   unaffected by raster band and/or palette subselection.

   Attributes will be carried across from the INPUT features to the respective 
   TILES features or get rejected to REJECTED output if REJECT_INVALID_GEOM is
   yes.

Output Tags

   The RasterSubsetFactory supports the following output tag.
   
   TILES 
   
      Output tiles created from splitting the input feature(s).

   REJECTED

      Features that got rejected outputted here with fme_rejection_code.