Raster Functions in ArcGIS AllSource
Raster functions are operations that apply processing directly to the pixels of imagery and raster datasets, as opposed to geoprocessing tools, which write out a new raster to disk. Calculations are applied to the pixels of the original data as the raster is displayed, so only pixels that are visible on your screen are processed. As you zoom and pan around, the calculations are performed on the fly. Since no intermediate datasets are created, processes can be applied quickly, as opposed to the time it would take to create a processed file on disk.
There are many of out-of-the-box functions that are provided in the software that can be used for radiometric correction, geometric correction, data management, visualization, and analysis. The Raster Functions pane can be accessed through the Analysis tab in the Raster group. Functions can be applied individually or combined to create function chains. There are several methods for applying functions depending on the structure of the dataset.
Use Raster Functions in the Raster Functions pane
ArcGIS AllSource provides many raster functions to process and analyze imagery and raster data. You can find the raster functions in the Raster Functions pane. The Raster Functions pane also allows users to view and change parameters that control how the functions processes data. You can also chain functions together to perform more complex analysis. These function chains can then be saved in a raster function template as an item to be reused later, just like any other function.
Intelligence Functions
Functions specific to ArcGIS AllSource are found in the Intelligence category.
NASA GeoCover land cover data is used to determine areas suitable for helicopter landing zones (HLZ). Input GeoCover categories are reclassified to Acceptable or Acceptable With Caution conditions in the output HLZ map.
Use the United States Geological Survey's (USGS) National Land Cover Database (NLCD) land-cover data to determine areas suitable for helicopter landing zones (HLZ) in the United States. Input NLCD categories are remapped into Acceptable and Acceptable With Caution categories.
The Slope Reclassify (Degrees) For HLZ Suitability function uses generic DEM (digital elevation model) raster data to determine if elevation changes in an area can support helicopter landing zone (HLZ) operations. The resulting data shows areas that are classified as Acceptable or Acceptable With Caution for a helicopter to land based on slope only.
General Raster Functions
Raster functions categories available in ArcGIS AllSource.