A script is a series of commands that tells an application to perform a series of operations. You can use scripts in most Adobe applications to automate repetitive tasks, perform complex calculations, and even use some functionality not directly exposed through the graphical user interface. For example, you can direct After Effects to reorder the layers in a composition, find and replace source text in text layers, or send an e-mail message when rendering is complete.
For a description of the scripting capabilities available with After Effects, see the After Effects Scripting Guide on the After Effects Developer Center.
When After Effects starts, it loads scripts from the Scripts folder. By default, the Scripts folder is in the following locations for After Effects:
(Windows) Program Files\Adobe\Adobe After Effects <version>\Support Files
(Mac OS) Applications/Adobe After Effects <version>
Several scripts come with After Effects and are automatically installed in the Scripts folder.
Loaded scripts are available from the File > Scripts menu. If you edit a script while After Effects is running, you must save your changes for the changes to be applied. If you place a script in the Scripts folder while After Effects is running, you must restart After Effects for the script to appear in the Scripts menu, though you can immediately run the new script using the Run Script File command.
Scripts in the ScriptUI Panels folder are available from the bottom of the Window menu. If a script has been written to provide a user interface in a dockable panel, the script should be put in the ScriptUI folder. ScriptUI panels work much the same as the default panels in the After Effects user interface.
By default scripts are not allowed to write files or send or receive communication over a network. To allow scripts to write files and communicate over a network, choose Edit > Preferences > General (Windows) or After Effects > Preferences > General (Mac OS), and select the Allow Scripts To Write Files And Access Network option.
To run a loaded script, choose File > Scripts > [script name].
To run a script that has not been loaded, choose File > Scripts > Run Script File, locate and select a script, and click Open.
To stop a running script, press Esc.
To run a script from the command line, call afterfx.exe from the command line. Use the -r switch and the full path of the script to run as arguments. This command does not open a new instance of the After Effects application; it runs the script in the existing instance.
Example (for Windows):afterfx -r c:\script_path\example_script.jsx
You can use this command-line technique—together with the software that comes with a customizable keyboard—to bind the invocation of a script to a keyboard shortcut.
Jeff Almasol provides a script that creates a simple console panel. The console panel includes a text area in which you can enter ExtendScript commands to be evaluated. There is no capturing of errors or messages; this console is only a simple way of entering commands without having to create a script first. For information, see Jeff Almasol's redefinery website.
On the AE Scripts website, Lloyd Alvarez offers a tip on how to run .jsxbin scripts if you don't have access to the Scripts or ScriptUI Panels folder.
After Effects provides several prewritten scripts to assist you in performing common tasks, and to provide a basis for you to modify and create your own scripts.
Run the sample script Demo Palette.jsx to get an idea of what sorts of things you can do with scripts.
You can write your own scripts for use in After Effects by using the script editor, which is part of the ExtendScript Toolkit. The ExtendScript Toolkit provides a convenient interface for creating, debugging, and testing your own scripts. Sometimes, all that you need to do is make a slight modification to an existing script to make it do what you want; such slight modifications can often be performed with little knowledge of computer programming and scripting languages.
See the After Effects scripting guide for more information.
A tutorial on the AE Enhancers forum leads the reader step by step through the creation of a script.
Jeff Almasol provides a set of scripting utilities—such as useful functions—to facilitate the creation of your own scripts on his redefinery website.
David Torno provides a list of matchnames for After Effects scripts.
Find scripts, projects, and other useful items on the Adobe Add-ons website.
Dan Ebberts provides scripting tutorials and useful scripts in the scripting section of his MotionScript website.
Lloyd Alvarez provides a collection of useful scripts on his After Effects Scripts website.
The AE Enhancers forum provides example scripts and useful information about scripting (as well as expressions and animation presets) in After Effects.
Jeff Almasol provides a collection of useful scripts on his redefinery website.
Dale Bradshaw provides scripts and tricks on his Creative Workflow Hacks website.
The nabscripts website provides many useful scripts.
Christopher Green provides many useful scripts on his website.