Raster analysis settings

Available with Standard or Advanced license.

Overview

Raster analysis settings are additional parameters that affect the output created when submitting a raster function template to ArcGIS Enterprise portal for processing. They differ from normal tool parameters in that they don't appear on the function Parameters tab; rather, they are values you set on the Settings tab during the Output Generation step. Once you set these output settings, they are interrogated and used by the raster function template or function chain when they are run. These settings help ensure consistency, and that processing is performed according to well-defined standards that control the parameters of your project, such as defining the geographic processing extent, the coordinate system for all outputs, or the cell size of output web image layers.

Notes

Specify raster analysis settings for each Enterprise portal job on the Settings tab of the Output Generation page.

Settings are not maintained between jobs.

When specifying Intersection of Inputs as your processing extent, it is possible that none of the features or cells overlap and that a null extent (zero width and height) may result. In such cases, no features or cells will be processed.

The Extent setting defines which rasters will be processed by a tool. It is useful when you need to process only a portion of a larger dataset. You can think of this setting as a rectangle used to select input features and rasters for processing. The extent of the output dataset will typically be larger than the Extent setting to account for features or cells that pass through the extent rectangle.

The Snap Raster setting is used to snap or align an extent during execution. The lower left corner of the extent is snapped to a cell corner of the snap raster and the upper right corner is adjusted using the output cell size. As a result, when the output cell size is the same as the snap raster cell size, the cells in the output raster are aligned with the cells of the snap raster.

Parameters

Parameter name	Description
Output Coordinate System	Specify the output coordinate system of web image layers created by raster analysis on Portal for ArcGIS. Select Coordinate System button —Choose the coordinate system for the output web image layer in the Spatial Reference dialog box. Current Map <name>—Use the coordinate system of the active map or scene view. Same as Layer <name>—All layers are listed, and you can choose one as the coordinate system. If you do not set the Output Coordinate System, the spatial reference of the output web layer will be the same spatial reference as the input raster.
Extent	The output extent setting will only process features or rasters that fall within the specified extent. Default—The tool you are using will determine the processing extent based on the inputs. Union of Inputs—The combined extent of all input data. Intersection of Inputs—The extent where all input rasters overlap or intersect one another. Current Display Extent—The extent of the current display will be used. As Specified Below <name>—The coordinates of the layer selected are displayed and can be modified (Left, Right, Top, and Bottom).
Snap Raster	The Snap Raster setting will adjust the extent of the output web image layer so that they match the cell alignment of the specified snap raster. The raster used for snapping must be a web image layer. You can specify the Snap Raster in two ways: Browse to an image service or select from the filtered pick list. Enter a URL to a web image layer.
Cell Size	Sets the output raster cell size or resolution. Maximum of Inputs—Use the largest cell size of all input datasets. This is the default. Minimum of Inputs—Use the smallest cell size of all input datasets. Same as Layer <name>—Use the cell size of the specified layer or raster dataset. The default is Maximum of Inputs.
Cell Size Projection Method	The Cell Size Projection Method determines how the output raster cell size will be calculated when datasets are projected during analysis. Convert units— Units are converted based on the types of coordinate systems involved. When projecting from one projected coordinate system (PCS) to another PCS, linear units are converted by the relevant factor. When transforming from one geographic coordinate system (GCS) to another GCS, angular units are converted. When projecting from GCS to PCS, or PCS to GCS, the output cell size is calculated based on the average of the ratios of the four sides and the two diagonals of the projected extent to the original extent. This is the default. Preserve resolution— The same number of square cells are preserved in the projected extent as are in the original extent. The output cell size is calculated based on the ratios of the areas of the projected extent to the original extent. Center of extent— The center of the original extent is projected to the output coordinate system. The output cell size is calculated by taking the average of the projected distances from the center point to its four adjacent points. The default is Convert units.
Resampling Method	Resampling is the process of interpolating the cell values while transforming your raster dataset. This is used when the input and output do not line up exactly, the cell size changes, the data is shifted, or a combination of these. There are three resampling methods to choose from when creating the output: Nearest Neighbor—Performs a nearest neighbor assignment, which is the fastest of the interpolation methods. It is used primarily for discrete data, such as a land-use classification, since it will not change the values of the cells. The maximum spatial error will be half the cell size. Bilinear—Performs a bilinear interpolation and determines the new value of a cell based on a weighted distance average of the four nearest input cells. It is useful for continuous data and will cause some smoothing of the data. Cubic—Performs a cubic convolution and determines the new value of a cell based on fitting a smooth curve through the 16 nearest input cells. It is appropriate for continuous data, although it may result in the output raster containing values outside the range of the input raster. It produces a raster that is geometrically less distorted than those achieved using the nearest neighbor resampling algorithm. The disadvantage of the Cubic option is that it requires more processing time.