Adobe 65009963 - After Effects CS4 User manual

SCRIPTING GUIDE

© Copyright 2007 Adobe Systems Incorporated. All rights reserved.
Adobe®Creative Suite 3 After Effects®Scripting Guide
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3
Overview
The After Effects Scripting Guide demonstrates how to take procedural control of your After Effects projects via
scripting. This feature set is available in Adobe® After Effects® CS3 Professional Edition.
With the use of system-level scripting, you can streamline your render pipeline and avoid a lot of repetitive
pointing and clicking. If you have used expressions or other JavaScript-like techniques for animating, or
worked with system scripting in AppleScript or Visual Basic, you will recognize the power of application
scripting in After Effects. With some practice, and with sufficient experience using the JavaScript language, you
can take control of your graphics pipeline.
If you are new to scripting
After Effects is a visual tool with a graphical user interface; you are used to interacting with it via interface
elements such as menus, panels, and icons. For the most part, this is the most accessible way to work. Scripting
is designed for situations in which this methodology involves tedious repetition or painstaking searching and
sorting that could be automated. Scripting can be a shortcut around tedious tasks that would otherwise involve
repetitious pointing and clicking. It is also useful for leveraging the power of networked rendering in situations
where Watch Folder is less powerful (and less convenient to set up). See “Examples” on page 173 for examples
of what scripts can do.
If you are new to scripting, see Adobe Introduction to Scripting, which introduces basic scripting concepts and
describes different scripting languages that are available, including JavaScript. JavaScript and other scripting
languages are object-oriented, and this book also describes the basic concepts of object-oriented programming
and document object models.
Even if you have no inclination to learn the JavaScript language, you can still harness the power of scripting via
third-party solutions such as Rush Network Render Queue, a graphical user interface to set up distributed
renders from any computer on the network without having to set up on individual machines.
You can also leverage the contributions of scripting users who share scripts with other users. Larger studios
may have such users in-house, while other users can visit forums such as those found at
www.adobeforums.com.
About this guide
This guide is for users who manage a graphics pipeline (which may include other scriptable applications as
well) and who want to write scripts to add custom capabilities to After Effects.
This functionality is also offered via third-party network rendering management solutions. These products
feature software designed to help manage this process, so it is possible to take advantage of this functionality
without having to perform manual editing of scripts.

4
Overview Editingscripts
4
The heart of a scriptable application is the object model. When you use Adobe After Effects, you create
projects, compositions, and render-queue items along with all of the elements that they contain: footage,
images, solids, layers, masks, effects, and properties. Each of these items, in scripting terms, is an object. This
guide describes the JavaScript objects that have been defined for After Effects projects.
Much of what scripting can accomplish replicates what can be done via the After Effects user interface, so a
thorough knowledge of the application itself is also essential to understanding how to use this functionality.
The After Effects object model is composed of a project, items, compositions, layers, and render-queue items.
Each object has its own special attributes, and every object in an After Effects project has its own identity
(although not all are accessible to scripting). You should be familiar with the After Effects object model in
order to create scripts.
After Effects scripting is based on ECMAScript (or more specifically, the 3rd Edition of the ECMA-262
Standard). Further documentation on this standard can be found at www.ecma-international.org. To take full
advantage of what is possible with scripting you will also need an understanding of writing scripts at the
system level (for integration with AppleScript or the Terminal command line in Mac OS and command-line
scripts on Windows systems) and a background in how to work with JavaScript.
NOTE: JavaScript objects normally referred to as “properties” are consistently called “attributes” in this guide, to
avoid confusion with After Effects’ own definition of a property (an animatable value of an effect, mask, or
transform within an individual layer).
Expressions
Although both After Effects expressions and the After Effects scripting interface use JavaScript and can access
individual layer properties, they are entirely distinct entities. Expressions cannot access information from
scripts (such as variables and functions), although a script can be written to create or edit an expression.
Because both expressions and scripting use JavaScript, familiarity with either one is helpful in understanding
the other.
Motion math
Motion math is no longer included in After Effects; its functionality has been superseded by scripting and
expressions. All mathematical and logical operators common to ECMAScript are available in scripting.
For example, with expressions it is possible to simulate the physics of a bouncing ball by applying mathe-
matical rules to a “ball” layer. But using scripting, you can create a whole user interface that allows a bouncing
ball and shadow layer to be animated using criteria entered by the user.
Editing scripts
After Effects includes a JavaScript editor. To start it, choose File > Scripts > Open Script Editor. This script
editor and debugger, called the ExtendScript Toolkit, provides a convenient interface for creating and testing
your own scripts.
You can use any text editor to create, edit, and save scripts, but it is recommended that you choose an appli-
cation that does not automatically add header information when saving files and that saves with Unicode
(UTF-8) encoding.
•Windows applications that are useful for editing scripts include EM Editor or the built-in Notepad (be sure
to set Encoding within save options to UTF-8).
•Mac OS applications that are useful for editing scripts include BBEdit or the built-in OS X TextEdit (be sure
to set the Save type in Preferences to Unicode [UTF-8]).

5
Overview Activating full scripting features
5
The ExtendScript JSX format
After Effects supports ExtendScript, Adobe’s extended implementation of JavaScript. ExtendScript is used by
all Adobe applications that provide a scripting interface. In addition to implementing the JavaScript language
according to the ECMA 262 and E4X ECMA 357 specifications, ExtendScript provides certain additional
features and utilities:
ExtendScript Toolkit: For help in developing, debugging, and testing scripts, ExtendScript provides an inter-
active development and testing environment, the ExtendScript Toolkit. It also defines a global debugging
object, the dollar ($) object, and a reporting utility for ExtendScript elements, the ExtendScript Reflection
interface.
File and Folder Objects: Because path name syntax is very different in different operating systems, Adobe
ExtendScript defines File and Folder objects to provide platform-independent access to the underlying file
system.
ScriptUI User Interface Module: The ExtendScript ScriptUI module provides the ability to create and interact
with user interface elements. ScriptUI provides an object model for windows and UI control elements that
you can use to create a user interface for your scripts.
Tools and Utilities: In addition, ExtendScript provides tools and features such as a localization utility for
providing user-interface string values in different languages and global functions for displaying short
messages in dialog boxes (alert, confirm, and prompt).
Interapplication Communication: ExtendScript provides a common scripting environment for all Adobe
applications, and allows interapplication communication through scripts.
External Communication: ExtendScript provides a Socket object that allows you to communicate with remote
systems from your After Effects scripts.
These features and more are described in detail in the JavaScript Tools Guide, which is available with After
Effects, and from partners.adobe.com.
ExtendScript script files are distinguished by the .jsx file extension, a variation on the standard .js extension
used with standard JavaScript files. After Effects scripts must include the .jsx file extension in order to be
properly recognized by the application. Any UTF-8 encoded text file with the .jsx extension is recognized as
an ExtendScript file.
You can use the ExtendScript Toolkit to export a binary version of an ExtendScript file, which has the
extension .jsxbin. Such a binary file may not be usable with all of the scripting integration features in After
Effects.
Activating full scripting features
For security reasons, the scripting features that operate outside the After Effects application (such as adding
and deleting files and folders on volumes, or accessing the network) are disabled by default.
To enable these features, choose Preferences > General, and select “Allow Scripts To Write Files And Access
Network.” This allows you to:
•Write to files
•Create folders and set the current folder
•Create a socket connection (for details of this JavaScript utility, see the JavaScript Tools Guide)

6
Overview Accessing and writing scripts
6
Adobe supplies a full-featured JavaScript debugger, called the ExtendScript Toolkit. The Toolkit is disabled by
default so that casual users do not encounter it. When editing or writing scripts, the Toolkit can help you
diagnose script problems more quickly. To activate the Toolkit on the local computer when a script error is
encountered, choose Preferences > General, and select Enable JavaScript Debugger. For detailed information
on the ExtendScript Toolkit, see the JavaScript Tools Guide.
Note that the Toolkit operates only when executing a script, not with expressions, even though expressions
also make use of JavaScript.
Accessing and writing scripts
To create and edit scripts for After Effects, you can use the ExtendScript Toolkit, or an external text-editing
application that creates files with Unicode UTF-8 text encoding. Beware of applications such as Microsoft
Word that by default add header information to files; these create line 0 errors in scripts, causing them to fail.
A script can reside anywhere, although to appear in the Scripts menu it must be saved in the Scripts folder
within the After Effects application folder.
There is no built-in method for recording a series of actions in After Effects into a script, as you can with
Adobe Photoshop® actions. Scripts are created outside After Effects and then executed within it, or externally
via a command-line, the ExtendScript Toolkit, or third-party render management software.
The Scripts menu and Scripts folder
After Effects scripts reside in the Scripts folder, within the same folder as your After Effects application file.
Only scripts contained in this Scripts folder when the application starts are automatically listed in the Scripts
menu, although a script file can reside anywhere.
To run a script that does not appear in the Scripts menu, choose File > Scripts > Run Script File, and choose
the script in the Open dialog box. Alternatively, you can send After Effects a script from the ExtendScript
Toolkit, from a command line (on Windows) or from AppleScript (on Mac OS).
To appear in the Open dialog box, your script must include the proper .jsx file extension.
Shutdown and Startup folders
Within the Scripts folder are two folders called Startup and Shutdown. After Effects runs scripts in these
folders automatically, in alphabetical order, on starting and quitting, respectively.
In the Startup folder you can place scripts that you wish to execute at startup of the application. They are
executed after the application is initialized and all plug-ins are loaded.
Scripting shares a global environment, so any script executed at startup can define variables and functions that
are available to all scripts. In all cases, variables and functions, once defined by running a script that contains
them, persist in subsequent scripts during a given After Effects session. Once the application is quit, all such
globally defined variables and functions are cleared. Be sure to give variables in scripts unique names, so that
a script does not inadvertently reassign global variables intended to persist throughout a session.
Attributes can also be added to existing objects such as the Application object (see “Application object” on
page 19) to extend the application for other scripts.
The Shutdown folder scripts are executed as the application quits. This occurs after the project is closed but
before any other application shutdown occurs.

7
Overview Sending a script to After Effects from the system
7
The Window menu and ScriptUI Panels folder
Within the Scripts folder, you can create another folder named ScriptUI Panels. Use this folder for scripts
whose user interface appears in a native panel (as opposed to a floating palette, dialog box, or window). The
advantage of a panel is that it can be docked with other panels, such as Project, Composition, and Time
Controls, and appear more integrated into the application. Like native panels, ScriptUI Panels scripts are
accessed from the Window menu.
Instead of creating a Window object an adding controls to it, a ScriptUI Panels script uses the "this" object that
represents the panel. For example, the following code adds a button to a panel:
var myPanel = this;
myPanel.add("button", [10, 10, 100, 30], "Tool #1");
myPanel.show();
If your script creates its user interface in a function, you cannot use "this" as it will refer to the function itself,
not the panel. In this case, you should pass the "this" object as an argument to your function. For example:
function createUI(thisObj) {
var myPanel = thisObj;
myPanel.add("button", [10, 10, 100, 30], "Tool #1");
return myPanel;
}
var myToolsPanel = createUI(this);
myToolsPanel.show();
You cannot use the File > Scripts > Run Script File menu command to run a script that refers to "this". To
make your script work with either a Window object (accessible from the File > Scripts menu) or a native panel
(accessible from the Window menu), check whether "this" is a Panel object. For example:
function createUI(thisObj) {
var myPanel = (thisObj instanceof Panel) ? thisObj : new Window("palette", "My Tools",
[100, 100, 300, 300]);
myPanel.add("button", [10, 10, 100, 30], "Tool #1");
return myPanel;
}
var myToolsPanel = createUI(this);
myToolsPanel.show();
Sending a script to After Effects from the system
If you are familiar with how to run a script from the command line in Windows or via AppleScript, you can
send a script directly to the open After Effects application, so that the application automatically runs the script.
How to include After Effects scripting in a command line (Windows)
Following are examples of Windows command-line entries that will send an After Effects script to the appli-
cation without using the After Effects user interface to execute the script.
In the first example, you copy and paste your After Effects script directly on the command line and then run
it. The script text appears in quotation marks following the afterfx.exe -s command:
afterfx.exe -s "alert("You just sent an alert to After Effects")"

8
Overview Testing and troubleshooting
8
Alternatively, you can specify the location of the JSX file to be executed. For example:
afterfx.exe -r c:\myDocuments\Scripts\yourAEScriptHere.jsx
afterfx.exe -r "c:\myDocuments\Scripts\Script Name with Spaces.jsx"
How to include After Effects scripting in an AppleScript (Mac OS)
Following are three examples of AppleScript scripts that will send an existing JSX file containing an After
Effects script to the application without using the After Effects user interface to execute the script.
In the first example, you copy your After Effects script directly into the Script Editor and then run it. The script
text appears within quotation marks following the DoScript command, so internal quotes in the script must
be escaped using the backslash escape character, as follows:
tell application "Adobe After Effects CS3"
DoScript "alert(\"You just sent an alert to After Effects\")"
end tell
Alternatively, you could display a dialog box asking for the location of the JSX file to be executed, as follows:
set theFile to choose file
tell application "Adobe After Effects CS3"
DoScript theFile
end tell
Finally, this script is perhaps most useful when you are working directly on editing a JSX script and want to
send it to After Effects for testing or to run. To use it effectively you must enter the application that contains
the open JSX file (in this example it is TextEdit); if you do not know the proper name of the application, type
in your best guess to replace “TextEdit” and AppleScript prompts you to locate it.
Simply highlight the script text that you want to run, and then activate this AppleScript:
(*
This script sends the current selection to After Effects as a script.
*)
tell application "TextEdit"
set the_script to selection as text
end tell
tell application "Adobe After Effects CS3"
activate
DoScript the_script
end tell
For more information on using AppleScript, check out Matt Neuberg’s AppleScript: the Definitive Guide
(O’Reilly & Associates) or Sal Soghoian’s AppleScript 1-2-3 (Peachpit Press).
Testing and troubleshooting
Any After Effects script that contains an error preventing it from being completed generates an error message
from the application. This error message includes information about the nature of the error and the line of
the script on which it occurred.

9
Overview More resources to learn scripting
9
Additionally, After Effects includes a JavaScript debugger. For more information on activating and using the
debugger, see the ExtendScript Toolkit documentation in the JavaScript Tools Guide.
More resources to learn scripting
Many resources exist for learning more about scripting that uses the ECMA standard.
The After Effects scripting engine supports the 3rd Edition of the ECMA-262 Standard, including its
notational and lexical conventions, types, objects, expressions, and statements.
For a complete listing of the keywords and operators included with ECMAScript, refer to ECMA-262.pdf,
available at www.ecma-international.org/publications/standards/Ecma-262.htm.
Books that deal with JavaScript 1.2 are also useful for understanding how scripting works in After Effects. One
book that is something of a standard for JavaScript users is JavaScript: The Definitive Guide (O’Reilly) by David
Flanagan. Another very readable source is JavaScript: A Beginner’s Guide (Osborne) by John Pollock. Both of
these texts contain information that pertains only to extensions of JavaScript for Internet browsers; however,
they also contain thorough descriptions of scripting fundamentals.
There are also books for using AppleScript and creating Windows command line scripts, each of which can be
used to send scripts to After Effects.
JavaScript variables
Scripting shares a global environment, so any script executed at startup can define variables and functions that
are available to all scripts. In all cases, variables and functions, once defined by running a script that contains
them, persist in subsequent scripts during a given After Effects session. Once the application is quit, all such
globally defined variables and functions are cleared. Scripters should be careful about giving variables in
scripts unique names, so that a script does not inadvertently reassign global variables intended to persist
throughout a session.
JavaScript keywords and statement syntax
Although it is not possible to provide an exhaustive resource describing usage of JavaScript, the following
tables provide an overview of keywords, statements, operators, precedence, and associativity.
The following table lists and describes all keywords and statements recognized by the After Effects scripting
engine.
Table 1 Keywords and Statement Syntax
Keyword/Statement Description
break Standard JavaScript; exit the currently executing loop.
continue Standard JavaScript; cease execution of the current loop iteration.
case Label used in a switch statement.
default Label used in a switch statement when a case label is not found.
do...while Standard JavaScript construct. Similar to the while loop, except loop condition evaluation occurs
at the end of the loop.
false Literal representing the boolean false value.
for Standard JavaScript loop construct.
for...in Standard JavaScript construct. Provides a way to easily loop through the properties of an object.

10
Overview More resources to learn scripting
10
JavaScript operators
The following tables list and describe all operators recognized by the After Effects scripting engine and show
the precedence and associativity for all operators.
Table 2 Description of Operators
function Used to define a function.
if/if...else Standard JavaScript conditional constructs.
new Standard JavaScript constructor statement.
null Assigned to a variable, array element, or object property to indicate that it does not contain a legal
value.
return Standard JavaScript way of returning a value from a function or exiting a function.
switch Standard JavaScript way of evaluating a JavaScript expression and attempting to match the expres-
sion’s value to a case label.
this Standard JavaScript method of indicating the current object.
true Literal representing the boolean true value.
undefined Indicates that the variable, array element, or object property has not yet been assigned a value.
var Standard JavaScript syntax used to declare a local variable.
while Standard JavaScript construct. Similar to the do...while loop, except loop condition evaluation
occurs at the beginning of the loop.
with Standard JavaScript construct used to specify an object to use in subsequent statements.
Operators Description
new Allocate object.
delete Deallocate object.
typeof Returns data type.
void Returns undefined value.
.Structure member.
[] Array element.
() Function call.
++ Pre- or post-increment.
–– Pre- or post-decrement.
–Unary negation or subtraction.
~Bitwise NOT.
!Logical NOT.
*Multiply.
/Divide.
%Modulo division.
Keyword/Statement Description

11
Overview More resources to learn scripting
11
Table 3 Operator Precedence
+Add.
<< Bitwise left shift.
>> Bitwise right shift.
>>> Unsigned bitwise right shift.
<Less than.
<= Less than or equal.
>Greater than.
>= Greater than or equal.
== Equal.
!= Not equal.
&Bitwise AND.
^Bitwise XOR.
|Bitwise OR.
&& Logical AND.
|| Logical OR.
?: Conditional (ternary).
=Assignment.
+= Assignment with add operation.
–= Assignment with subtract operation.
*= Assignment with multiply operation.
/= Assignment with divide operation.
%= Assignment with modulo division operation.
<<= Assignment with bitwise left shift operation.
>>= Assignment with bitwise right shift operation.
>>>= Assignment with unsigned bitwise right shift operation.
&= Assignment with bitwise AND operation.
^= Assignment with bitwise XOR operation.
|= Assignment with bitwise OR operation.
,Multiple evaluation.
Operators (highest precedence to lowest) Associativity
[], (), .left to right
new, delete, – (unary negation), !, typeof, void, ++, –– right to left
Operators Description

12
Overview More resources to learn scripting
12
*, /, % left to right
+, – (subtraction) left to right
<<, >>, >>> left to right
<, <=, >, >= left to right
==, != left to right
&left to right
^left to right
|left to right
&& left to right
|| left to right
?: right to left
=, /=, %=, <<=, >>=, >>>=, &=, ^=, |=, +=, –=, *= right to left
,left to right
Operators (highest precedence to lowest) Associativity

13
JavaScript Reference
This chapter lists and describes JavaScript classes, objects, methods, attributes, and global functions defined by
After Effects.
The After Effects scripting engine supports ExtendScript, Adobe’s extended version of JavaScript, which imple-
ments the 3rd Edition of the ECMA-262 Standard, including its notational and lexical conventions, types,
objects, expressions and statements. For a complete listing of the keywords and operators included with
ECMAScript, refer to ECMA-262.pdf, available at www.ecma-international.org/publications/standards/
Ecma-262.htm. For an overview of the most common keywords and statements available from ECMA-262,
see “JavaScript keywords and statement syntax” on page 9.
The After Effects Object Model
As you look through this reference section, which is organized alphabetically by object, you can refer to the
following diagrams for an overview of where the various objects fall within the hierarchy, and their correspon-
dence to the user interface.
Hierarchy diagram of the main After Effects scripting objects
Note that the File, Folder, and Socket objects are defined by ExtendScript, and are documented in the JavaS-
cript Tools Guide. ExtendScript also defines the ScriptUI module, a set of window and user-interface control
objects, which are available to After Effects scripts. These are also documented in the JavaScript Tools Guide.
The hierarchy of objects in scripting corresponds to the hierarchy in the user interface.
APPLICATION
PROJECT
SETTINGS
RENDER1UEUE ITEMS
ITEMSMAYBEANYOFTHEFOLLOWINGTYPESOFITEM
ITEMS
RENDER1UEUE)TEMS
OUTPUT-ODULES
SOCKETFILE FOLDERSYSTEM
FOLDER)TEMFOOTAGE)TEM
PROXY3OURCE PROXY3OURCEMAIN3OURCE
SOLID3OURCE
COLOR
FILE3OURCE
FILE
PLACEHOLDER3OURCE
LAYERS
PROPERTIES
COMP)TEM
/2
/2
/2
/2
MAIN3OURCEPROXY3OURCE
MAYBEANYOFTHEFOLLOWINGTYPESOFITEM

14
JavaScript Reference The After Effects Object Model
14
The application contains a Project panel, which displays a project. The project contains compositions, which
contain layers. The source for a layer can be a footage file, placeholder, or solid, also listed in the Project panel.
Each layer contains settings known as properties, and these can contain markers and keyframes. The render
queue contains render-queue items as well as render settings and output modules. All of these entities are repre-
sented by objects in scripting.
NOTE: To avoid ambiguity, this manual uses the term “attribute” to refer to JavaScript object properties, and the
term “property” or “AE property” to refer to After-Effects layer properties.
Object summary
The following table lists all objects alphabetically, with links to the documentation page for each.
Object Description
“Global functions” on page 16 Globally available functions that allow you to display text for script debugging purposes,
and help convert time values between seconds and frames.
“Application object” on page 19 A single global object, available by its name (app), that provides access to objects and
application settings within the After Effects application.
“AVItem object” on page 32 Represents audio/visual files imported into After Effects.
“AVLayer object” on page 39 Represents those layers that contain AVItem objects (Comp layers, footage layers, solid
layers, text layers, and sound layers).
“CameraLayer object” on page 50 Represents a camera layer within a composition.
“Collection object” on page 51 Associates a set of objects or values as a logical group and provides access to them by
index.
“CompItem object” on page 52 Represents a composition, and allows you to manipulate it and get information about it.

15
JavaScript Reference The After Effects Object Model
15
“FileSource object” on page 60 Describes footage that comes from a file.
“FolderItem object” on page 62 Represents a folder in the Project panel.
“FootageItem object” on page 64 Represents a footage item imported into a project, which appears in the Project panel.
“FootageSource object” on page 67 Describes the file source of some footage.
“ImportOptions object” on page 73 Encapsulates options for importing files into After Effects.
“Item object” on page 76 Represents an item in a project that appears in the Project panel.
“ItemCollection object” on page 79 Collects items in a project.
“KeyframeEase object” on page 81 Encapsulates keyframe ease values in an After Effects property.
“Layer object” on page 83 A base class for layer classes.
“LayerCollection object” on page 92 Collects layers in a project.
“LightLayer object” on page 97 Represents a light layer within a composition.
“MarkerValue object” on page 98 Encapsulates marker values in an AE property.
“MaskPropertyGroup object” on
page 102
Encapsulates mask attributes in a layer.
“OMCollection object” on page 104 Collects output modules in a render queue.
“OutputModule object” on page 105 Represents an output module for a render queue.
“PlaceholderSource object” on page 108 Describes a placeholder for footage.
“Project object” on page 109 Represents an After Effects project.
“Property object” on page 118 Represents an After Effects property.
“PropertyBase object” on page 140 A base class for After Effects property and property group classes.
“PropertyGroup object” on page 147 Represents an After Effects property group.
“RenderQueue object” on page 152 Represents the After Effects render queue.
“RenderQueueItem object” on page 155 Represents a renderable item in a render queue.
“RenderQueueItem object” on page 155 Collects render-queue items in a render queue.
“RQItemCollection object” on page 161 Provides access to application settings and preferences.
“Shape object” on page 164 Encapsulates the outline shape information for a mask.
“ShapeLayer object” on page 167 Represents a shape layer within a composition.
“SolidSource object” on page 168 Describes a solid color that is the source of some footage.
“System object” on page 169 Provides access to the operating system from the application.
“TextDocument object” on page 171 Encapsulates the text in a text layer.
“TextLayer object” on page 172 Represents a text layer within a composition.
Object Description

16
JavaScript Reference Globalfunctions
16
Global functions
These globally available functions that are specific to After Effects. Any JavaScript object or function can call
these functions, which allow you to display text in a small (3-line) area of the Info panel, and to convert
numeric time values to and from string values.
Additional global functions for standard user I/O (alert, confirm, and prompt) and static functions for file
I/O, are defined by ExtendScript; for detailed reference information, see the Adobe Bridge®JavaScript
Reference.
NOTE: The After Effects global functions for standard dialogs and file I/O are still supported in this release, but
are deprecated and will not be supported in future releases. For details, see the After Effects 6.5 documentation.
clearOutput() global function
clearOutput()
Description
Clears the output in the Info panel.
Parameters
None.
Returns
Nothing.
currentFormatToTime() global function
currentFormatToTime(formattedTime, fps, isDuration)
Description
Converts a formatted string for a frame time value to a number of seconds, given a specified frame rate. For
example, if the formatted frame time value is 0:00:12 (the exact string format is determined by a project
setting), and the frame rate is 24 fps, the time would be 0.5 seconds (12/24). If the frame rate is 30 fps, the time
would be 0.4 seconds (12/30).
If the time is a duration, the frames are counted from 0. Otherwise, the frames are counted from the project’s
starting frame (see “Project displayStartFrame attribute” on page 111).
Parameters
Global function Description
clearOutput() Clears text from the Info panel.
currentFormatToTime() Converts string time value to a numeric time value.
timeToCurrentFormat() Converts a numeric time value to a string time value.
write() Writes text to the Info panel, with no line break added.
writeLn() Writes text to the Info panel, adding a line break at the end.
formattedTime The frame time value, a string specifying a number of frames in the project’s current time display format.

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Returns
Floating-point value, the number of seconds.
timeToCurrentFormat() global function
timeToCurrentFormat(time, fps, isDuration)
Description
Converts a numeric time value (a number of seconds) to a frame time value; that is, a formatted string that
shows which frame corresponds to that time, at the specified rate. For example, if the time is 0.5 seconds, and
the frame rate is 24 fps, the frame would be 0:00:12 (when the project is set to Display Timecode). If the frame
rate is 30 fps, the frame would be 0:00:15. The format of the timecode string is determined by a project setting.
If the time is a duration, the frames are counted from 0. Otherwise, the frames are counted from the project’s
starting frame (see “Project displayStartFrame attribute” on page 111).
Parameters
Returns
String in the project’s current time display format.
write() global function
write(text)
Description
Writes output to the Info panel, with no line break added.
Parameters
Returns
Nothing.
Example
write("This text appears in Info panel ");
write("with more on same line.");
fps The frames-per-second, a floating-point value.
isDuration Optional. When true, the time is a duration (measured from frame 0). When false (the default), the time is
measured from the project’s starting frame.
time The number of seconds, a floating-point value.
fps The frames-per-second, a floating-point value.
isDuration Optional. When true, the time is a duration (measured from frame 0). When false (the default), the time is
measured from the project’s starting frame.
text The string to display. Truncated if too long for the Info panel.

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writeLn() global function
writeLn(text)
Description
Writes output to the Info panel and adds a line break at the end.
Parameters
Returns
Nothing.
Example
writeln("This text appears on first line");
writeln("This text appears on second line");
text The string to display.

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Application object
app
Description
Provides access to objects and application settings within the After Effects application. The single global object
is always available by its name, app.
Attributes of the Application object provide access to specific objects within After Effects. Methods of the
Application object can create a project, open an existing project, control Watch Folder mode, purge memory,
and quit the After Effects application. When the After Effects application quits, it closes the open project,
prompting the user to save or discard changes as necessary, and creates a project file as necessary.
Attributes
Attribute Reference Description
project “Application project attribute” on
page 28 and “Project object” on
page 109
The current After Effects project.
language “Application language attribute” on
page 24
The language in which the application is running.
version “Application version attribute” on
page 30
The version number of the After Effects application.
buildName “Application buildName attribute” on
page 21
The name of this build of the application.
buildNumber “Application buildNumber attribute” on
page 22
The number of this build of the application.
isWatchFolder “Application isWatchFolder attribute”
on page 24
When true, the local application is running in Watch
Folder mode.
isRenderEngine “Application isRenderEngine attribute”
on page 24
When true, the local After Effects application is running
as a render engine.
settings “Application settings attribute” on
page 30 and “RQItemCollection object”
on page 161
Application settings that can be set via scripting.
onError “Application onError attribute” on
page 26
A callback function that is called when an error occurs
in the application.
exitCode “Application exitCode attribute” on
page 24
A numeric status code used when executing a script
externally (that is, from a command line or AppleScript).
0 if no error occurred. A positive number indicates an
error that occurred while running the script.
exitAfterLaunchAndEval “Application exitAfterLaunchAndEval
attribute” on page 23
When true, the application remains open after running
a script from the command line on Windows.
saveProjectOnCrash “Application saveProjectOnCrash
attribute” on page 28
When true, the project is saved if the application closes
unexpectedly.
memoryInUse “Application memoryInUse attribute”
on page 25
Memory in use by this application.

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Methods
Application activate() method
app.activate()
Description
Opens the application main window if it is minimized or iconified, and brings it to the front of the desktop.
Parameters
None.
Method Reference Description
newProject() “Application newProject() method” on
page 25
Creates a new project in After Effects.
open() “Application open() method” on page 26 Opens a project or an Open Project dialog box.
quit() “Application quit() method” on page 28 Quits the application.
watchFolder() “Application watchFolder() method” on
page 30
Starts Watch Folder mode; does not return
until Watch Folder mode is turned off.
pauseWatchFolder() “Application pauseWatchFolder() method”
on page 27
Pauses a current watch-folder process.
endWatchFolder() “Application endWatchFolder() method” on
page 23
Ends a current watch-folder process.
purge() “Application purge() method” on page 28 Purges a targeted type of cached information
(replicates Purge options in the Edit menu).
beginUndoGroup() “Application beginUndoGroup() method”
on page 21
Groups the actions that follow it into a single
undoable step.
endUndoGroup() “Application endUndoGroup() method” on
page 22
Ends an undo group; needed only when a
script contains more than one undo group.
beginSuppressDialogs() “Application beginSuppressDialogs()
method” on page 21
Begins suppression of dialogs in the user inter-
face.
endSuppressDialogs() “Application endSuppressDialogs()
method” on page 22
Ends suppression of dialogs in the user inter-
face.
setMemoryUsageLimits() “Application setMemoryUsageLimits()
method” on page 29
Sets memory usage limits as in the Memory &
Cache preferences area.
setSavePreferencesOnQuit() “Application setSavePreferencesOnQuit()
method” on page 29
Sets whether preferences are saved when the
application is quit.
activate() “Application activate() method” on page 20 Brings the After Effects main window to the
front of the screen.
scheduleTask() “Application scheduleTask() method” on
page 29
Schedules a JavaScript script for delayed exe-
cution.
cancelTask() “Application cancelTask() method” on
page 22
Cancels a scheduled task.
parseSwatchFile() “Application parseSwatchFile() method” on
page 27
Loads a color swatch from an Adobe Swatch
Exchange (ASE) file.