Raster source data processing
Existing raster data can be processed so it can be used with Landscape Modeler. Preparing the data for use requires the following steps:
- Clipping the raster data
- Resizing the raster data
- Filling gaps in the data
- Removing extra zeroes from null values
Raster clipping
If necessary, use the Clip tool in the Raster Processing toolset in the Raster toolset in the Data Management toolbox to extract only the cells in the area of interest (AOI). Alternatively, you can use the Spatial Analyst Extract by Mask tool, with the AOI as the mask. This step is only necessary to reduce the size of the data on disk. If data size concern, it is more efficient to set the clip extent on the mosaic dataset using the Clip function; this workflow is described in Creating the mosaic dataset.
Raster data resizing
The raster can sometimes be stored at a smaller bit depth, depending on the max value of the attributes and AOI. This reduces storage space and processing time without detracting from the detail of the raster. This can be determined after clipping and reviewing the minimum and maximum values indicated in the raster statistics. Use the Copy Raster tool in the Raster Dataset toolset in the Data Management toolbox, and set the Pixel Type parameter to the appropriate output bit depth. This bit depth ranges from 1 bit to 64 bits.
Filling gaps in raster data
If necessary, cell values may need to be populated. This can be accomplished using the Raster Calculator in the Map Algebra toolset in the Spatial Analyst toolbox. Before running this tool, set the Processing Extent environment setting to the boundary layer. Use the following parameter values to run the tool.
Parameter name | Value |
|---|---|
Map Algebra Expression | Use one of the following, depending on the values in your rasters.
|
Output raster | <working directory> \ <name_rastercalc> |
Removing extra zeroes from null
If necessary, extra zeroes can be removed from raster cell values using the Set Null tool. This tool is in the Conditional toolset in the Spatial Analyst toolbox. Use the following parameter values to run the tool.
Parameter name | Value |
|---|---|
Input conditional raster | <source raster> |
Expression | "Value"=0 |
Input false raster or constant value | <source raster> |
Output raster | <working directory>\<final raster name> |