This task separates a raster into tiles based on number of pixels in the X and Y directions. In most cases the tiles in the last row and column will be smaller than the specified distance, as the following example shows:
Example
e = ENVI()
File = Filepath('qb_boulder_msi', Subdir=['data'], $
Root_Dir=e.Root_Dir)
Raster = e.OpenRaster(File)
Task = ENVITask('DiceRasterByPixel')
Task.INPUT_RASTER = Raster
Task.NUMBER_OF_X_PIXELS = 350
Task.NUMBER_OF_Y_PIXELS = 450
Task.TILE_GRID_VECTORS = 'true'
Task.OUTPUT_DIRECTORY = Filepath('', /TMP)
Task.Execute
DataColl = e.Data
DataColl.Add, Task.OUTPUT_RASTER
View1 = e.GetView()
FOR i=0,N_Elements(Task.Output_Raster)-1 DO $
Layer = View1.CreateLayer(Task.OUTPUT_RASTER[i])
vectorLayer = View1.CreateLayer(Task.OUTPUT_VECTOR)
View1.Zoom, /FULL_EXTENT
Syntax
Result = ENVITask('DiceRasterByPixel')
Input properties (Set, Get): INPUT_RASTER, NUMBER_OF_X_PIXELS, NUMBER_OF_Y_PIXELS, OUTPUT_DIRECTORY, TILE_GRID_VECTORS
Output properties (Get only): OUTPUT_RASTER, OUTPUT_VECTOR
Properties marked as "Set" are those that you can set to specific values. You can also retrieve their current values any time. Properties marked as "Get" are those whose values you can retrieve but not set.
Methods
This task inherits the following methods from ENVITask:
AddParameter
Execute
Parameter
ParameterNames
RemoveParameter
Properties
This task inherits the following properties from ENVITask:
COMMUTE_ON_DOWNSAMPLE
COMMUTE_ON_SUBSET
DESCRIPTION
DISPLAY_NAME
NAME
REVISION
TAGS
This task also contains the following properties:
INPUT_RASTER (required)
Specify the input raster.
NUMBER_OF_X_PIXELS (required)
Specify the number of pixels per tile in the X direction.
NUMBER_OF_Y_PIXELS (required)
Specify the number of pixels per tile in the Y direction.
OUTPUT_DIRECTORY (optional)
Specify the output directory for the tiles. If set to an asterisk (*), the output rasters will be virtual. This will not be written to disk, and the directory will not be created. If you do not set this property, the tiles will save to the directory indicated by the ENVI Output Directory preference.
OUTPUT_RASTER
This property contains an array of output rasters. Their filenames contain the root name of the input raster with the row/column index appended in the form of RxCx. For example, R2C3 means row 2 and column 3.
OUTPUT_VECTOR
This property contains the output shapefile if you set the TILE_GRID_VECTORS property to true.
TILE_GRID_VECTORS (optional)
Set this property to true to create an output shapefile that shows the tile boundaries.
Version History
ENVI 5.4 |
Introduced |
ENVI 5.5 |
OUTPUT_DIRECTORY now supports '*', which allows OUTPUT_RASTER to be virtual output.
|
API Version
4.3
See Also
ENVITask, ENVITask::Parameter, ENVISubsetRaster, CreateSubrectsFromDistance Task, CreateSubrectsFromPixels Task, CreateSubrectsFromTileCount Task, CreateSubrectsFromVector Task, DiceRasterByDistance Task, DiceRasterBySubrects Task, DiceRasterByTileCount Task, DiceRasterByVector Task, ExportRastersToDirectory Task