Raster Function Editor

The raster function editor is a visual programming interface for building imagery and raster analysis processing chains. The workflows can be saved as raster function templates (RFTs), which can automate your image analyses and processes. You can create and modify RFTs in the raster function editor. The raster function editor shows your function chain represented as a diagram that chains together sequences of functions, using the output of one or more functions as the input to another function.

You can also use the System pane to access the raster functions. Click the Add to Editor button to add a function.

Raster function editor capabilities

The function editor allows you to perform many different tasks, including the following:

• Visualize your workflow sequence as a processing diagram that is easy to understand.
• Build an RFT by adding raster functions, raster variables, scalars, raster layers, datasets, and other data types to the diagram, and connecting them to perform analysis. This analysis can be performed on the current display extent or in a distributed manner using raster analysis.
• Save a function raster layer's function chain as an RFT.
• Make your RFT easy to use for others, by renaming and sharing function names, raster variable names, and function variables names.

Raster function template

An RFT is similar to a model. An RFT can contain one or more raster functions chained together to create a processing workflow. The function editor contains tools to organize and manage the template that are available on the toolbar at the top of the Function Editor window.

The RFT below illustrates a methodology for describing burn severity and the health of vegetation recovery, using prefire and postfire imagery. The appropriate functions are placed in the editor and are interactively connected to the raster function template, where the output from a function is the input to the next function in the processing chain.

Create an RFT

Raster functions are fundamental building blocks of your RFT. There are many raster functions you can use for your imagery and raster related tasks. Once you know the functions needed for your task, you can add those functions to an RFT.

To create an RFT, follow the steps below.

1. Verify that you are signed in and have the privileges to create content.
2. Click the Analysis button .
3. In the Perform Analysis pane, click Raster Analysis, and click the Create a raster function template to perform complex processing and analysis button .

   An empty function editor window appears.

   The function editor window is divided into two parts, with the available functions listed in the System pane, and the raster function chain editing workspace next to it.

   The tools at the top of the window allow you to build and manage the RFT. You can use the tools to move and align layout, add a raster variable input, add a scalar input, and delete the function nodes.

4. In the System pane, type Slope in the search field, and click the Add Function button to add the raster function to the editing window.
5. In the System pane, type Remap in the search field, and click the Add Function button to add the raster function to the editing window.
6. Click the Add Raster Variable button to add the data source input to the raster function chain.

   You can link two nodes by clicking and dragging an edge of the raster function source node toward the target raster function node, creating a link between the two.

7. Click the edge of the green Add Raster Variable node and connect it to the Slope raster function node (DEM).
8. Click the edge of the Slope node (Out) and connect it to the Remap raster function node (Raster).
9. Click the Layout button at the top of the editor window to organize the layout of the raster function chain.

   The function nodes of the processing chain are connected and the layout is organized.

   

10. Double-click the Slope function node to set the raster function parameters.

    The property page appears with the following tabs:

    • General—Provide a name and description for the function. This is useful when you create a raster function chain with multiple functions. The name of the function can describe what the function does, so any member of your Enterprise that uses the function can understand how the function chain is used. Set the Output Pixel Type option; if it's not set, the output type will match the input pixel type.
    • Parameters—Edit parameters of the function.
    • Variables—Show function parameters to Enterprise members. You can set the parameters to be public (InPublic). You can also rename parameters, such as variable Name, to provide additional context.

11. When the function chain has been created, click Save.
12. In the Save dialog box, provide a title, tags, and an output folder.
13. Click OK at the bottom of the page.

    Your new function chain appears on the Analysis page.

    The Analysis page contains a panel summarizing each raster function in your processing chain. You can verify your parameter settings for each function and Show Preview of the processing chain result. If the results are unsatisfactory, you can change the parameter settings and display the preview results again.

14. Click Run Analysis to run the processing chain.

    The results of your raster function processing chain appear in Map Viewer or other display client.

Edit an existing RFT

You can edit and apply an existing RFT by following the steps below.

1. Verify that you are signed in and have the privileges to create content.
2. Click the Analysis button .
3. In the Perform Analysis pane, click the Browse Raster Function Templates and Custom Web Tools button .

   The Custom Analysis Tools portal content page appears.

4. In the Filter panel, click Item Type > Raster Function Templates to display a list of saved RFTs.
5. Find your RFT in the list, click the drop-down arrow on the Select button, and click Edit.

   The RFT is available for editing in the raster function editor.