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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.
Note: Scripts created in After Effects 6.5 or earlier that use an index to access a property may not work as expected in After Effects 7 or later. To resolve this issue, modify your scripts so that they contain equivalent expressions accessing properties by name.
The default is for scripts to not be 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 start the script editor, choose File Scripts Open Script Editor.
AFTER EFFECTS CS3 46 User Guide For a complete description of the scripting capabilities available with After Effects, see the After Effects Scripting Guide on the Adobe website at www.adobe.com/devnet/aftereffects.
To exchange scripts and other useful tools with other After Effects users, visit the After Effects Exchange on the Adobe website at www.adobe.com/go/learn_ae_exchange.
Jeff Almasol provides a collection of useful scripts on his website: www.adobe.com/go/learn_ae_redefineryhome.
Dan Ebberts provides scripting tutorials and useful scripts on his website:
The AE Enhancers forum provides example scripts and useful information about scripting (as well as expressions and animation presets) in After Effects: www.adobe.com/go/learn_ae_aeenhancershome.
This tutorial on the AE Enhancers forum leads the reader step by step through the creation of a script:
Chapter 4: Importing
Importing and interpreting footage items Working with imported files You import footage items into a project and use them as sources for layers. You work with collections of layers in a composition to animate, composite, and apply effects. You can import many different kinds of files, collections of files, or components of files as sources for individual footage items, including moving image files, still-image files, still-image sequences, and audio files. You can even create footage items yourself within After Effects, such as solids and precompositions. You can import footage items into a project at any time.
When you import files, After Effects does not copy the image data itself into your project but creates a reference link to the footage item in the Project panel. This keeps project files relatively small.
If you delete, rename, or move an imported source file, you break the reference link to that file. When a link is broken, the name of the source file appears in italics in the Project panel, and the File Path column lists it as missing. If the footage item is available, you can reestablish the link—usually just by double-clicking the item and selecting the file again.
To reduce rendering time and increase performance, it is often best to prepare footage before you import it into After Effects. For example, it is often better to scale or crop a still image in Photoshop before you bring it into After Effects, rather than scaling and cropping the image in After Effects. It is better to perform an operation once in Photoshop than to force After Effects to perform the same action many times per second—once for each frame in which the image appears.
You can use the Footage panel to evaluate footage and perform simple editing tasks, such as trimming a footage item’s duration.
To save time and minimize the size and complexity of a project, import a footage item once and then use it multiple times in a composition. It is occasionally useful, however, to import a footage item more than once, such as when you want to use it at two different frame rates.
If you use another application to modify a footage item that is used in a project, the changes appear in After Effects the next time that you open the project or select the footage item and choose File Reload Footage.
To replace a layer’s source footage item with another footage item, without affecting edits made to the layer properties, select the layer and then Alt-drag (Windows) or Option-drag (Mac OS) the new footage item onto the layer in the Timeline panel.
For introductions to digital video, digital audio, high-definition video, DVD, compression, and streaming video, visit the Adobe website at www.adobe.com/go/learn_dv_primers.
Supported import formats Some file-name extensions—such as MOV and AVI—denote container file formats rather than denoting a specific audio, video, or image data format. Container files can contain data encoded using various compression and encoding schemes. After Effects can import these container files, but the ability to import the data that they contain is dependent on which codecs (specifically, decoders) are installed.
By installing additional codecs, you can extend the ability of After Effects to import additional file types. Most codecs must be installed into the operating system (Windows or Mac OS) and work as a component inside the QuickTime or Video for Windows formats. Contact the manufacturer of your hardware or software for more information about codecs that work with the files that your specific devices or applications create.
The Automatic Duck Pro Import AE tool extends your ability to import assets in various formats, including those
used by popular non-linear editing systems. For more information, see the Automatic Duck website:
• Advanced Audio Coding (AAC, M4A)
• Audio Interchange File Format (AIF, AIFF)
• MP3 (MP3, MPEG, MPG, MPA, MPE)
• Video for Windows (AVI, WAV; requires QuickTime on Mac OS)
• Waveform (WAV)
• Radiance (HDR, RGBE, XYZE; 32 bpc)
• SGI (SGI, BW, RGB; 16 bpc)
• Softimage (PIC)
• Targa (TGA, VDA, ICB, VST)
• TIFF (TIF) You can import files of any still-image format as a sequence. See “Importing still images” on page 80.
Video and animation formats
• Animated GIF (GIF)
• DV (in MOV or AVI container, or as containerless DV stream)
• ElectricImage (IMG, EI)
• Filmstrip (FLM)
• Flash (SWF; continuously rasterized) Note: SWF files are imported with an alpha channel. Interactive content and scripted animation are not retained.
Animation defined by keyframes is retained.
• Media eXchange Format (MXF; Op-Atom variety used by Panasonic DV, DVCPRO, DVCPRO50, and DVCPRO HD video cameras to record to Panasonic P2 media)
• MPEG-1, MPEG-2, and MPEG-4 formats (MPEG, MPE, MPG, M2V, MPA, MP2, M2A, MPV, M2P, M2T, AC3, MP4, M4V, M4A) Note: Some MPEG data formats are stored in container formats with file-name extensions that are not recognized by After Effects; examples include.vob and.mod. In some cases, you can import these files into After Effects after changing the file-name extension to one of the recognized file-name extensions. Due to variations in implementation in these container formats, compatibility is not guaranteed.
• Open Media Framework (OMF; raw media [or essence] only; Windows only)
• QuickTime (MOV; 16 bpc, requires QuickTime)
• Adobe Photoshop with video layer (PSD; requires QuickTime)
• Video for Windows (AVI, WAV; requires QuickTime on Mac OS) You can import 10-bpc uncompressed YUV AVI files created in Adobe Premiere Pro into 16-bpc RGB After Effects projects. You can also render with 10-bpc YUV compression. (See “Specify Video for Windows compression options” on page 620.)
• Windows Media File (WMV, WMA, ASF; Windows only)
For information on importing Apple Motion projects into After Effects, see the Apple website:
See also “Supported output formats” on page 588 “Import assets in Panasonic P2 format” on page 73 Import footage items You can import media files into your project either by using the Import dialog box or by dragging. If the Interpret Footage dialog box appears after you import a footage item, it contains an unlabeled alpha channel, and you must select an alpha channel interpretation method or click Guess to let After Effects determine how to interpret the alpha channel.
Imported footage items appear in the Project panel.
See also “Specify alpha channel interpretation” on page 52 “Import a single still image or a still-image sequence” on page 81 “Shortcuts for working with footage” on page 644 Import footage items using the Import dialog box 1 Choose File Import File or File Import Multiple Files, or double-click an empty area of the Project panel.
If you choose Import Multiple Files, then you can perform the next step more than once without needing to choose an Import command multiple times.
To display only supported footage files (excluding project files), choose All Footage Files from the Files Of Type (Windows) or Enable (Mac OS) menu.
2 Do one of the following:
• Select a file, and then click Open.
• Ctrl-click (Windows) or Command-click (Mac OS) multiple files to select them, and then click Open.
• Click a file and then Shift-click another file to select a range of files, and then click Open.
• Select an entire folder, and then click Import Folder.
Note: If the Sequence option is selected, multiple files from the folder will be imported as a sequence of still images.
Interpret footage items After Effects uses a set of internal rules to interpret each footage item that you import according to its best guess for the source file’s pixel aspect ratio, frame rate, color profile, and alpha channel type. If After Effects guesses wrong, or if you want to use the footage differently, you can modify these rules for all footage items of a particular kind by editing the interpretation rules file (interpretation rules.txt), or you can modify the interpretation of a specific footage item using the Interpret Footage dialog box.
The interpretation settings tell After Effects the following about each footage item:
• How to interpret the alpha channel’s interaction with other channels. (See “Specify alpha channel interpretation” on page 52.)
• What frame rate to assume for the footage item. (See “Change frame rate” on page 53.)
• Whether to separate fields and, if so, what field order to assume. (See “Separate video fields” on page 71 and “Determine the original field order” on page 72.)
• Whether to remove 3:2 or 24Pa pulldown. (See “Remove 3:2 or 24Pa pulldown from video” on page 72.)
• The pixel aspect ratio of the footage item. (See “Change pixel aspect ratio” on page 55.)
• The color profile of the footage item. (See “Interpret a footage item by assigning an input color profile” on page 245.) Important: In all of these cases, the information is used to make decisions about how to interpret data in the imported footage item. The interpretation settings in the Interpret Footage dialog box should match the settings used to create the source footage file. These settings are not to be used to specify settings for your final rendered output.
Generally, you don’t need to change interpretation settings. However, if a footage item isn’t of a common kind, After Effects may need additional information from you to interpret it correctly.
You can use the controls in the Color Management section of the Interpret Footage dialog box to tell After Effects how to interpret the color information in a footage item. This is usually only necessary when the footage item does not contain an embedded color profile.
See also “Shortcuts for working with footage” on page 644 Interpret a single footage item using the Interpret Footage dialog box ❖ Select a footage item in the Project panel and choose File Interpret Footage Main.
Edit interpretation rules for all items of a specific kind The interpretation rules file contains the rules that specify how After Effects interprets footage items. In most cases, you won’t need to customize the interpretation rules file. When you import a footage item, After Effects looks for a match in the interpretation rules file, and then determines interpretation settings for the footage item. You can override these settings after importing, using the Interpret Footage dialog box.
In most cases, the name of the interpretation rules file is interpretation rules.txt; however, some updates to After Effects install a new interpretation rules file with a name that indicates the updated version number, and the updated application uses this new file. If you have made changes to the old interpretation rules file, you may need to apply those changes to the new file, too.
1 Quit After Effects.
2 As a precaution, make a backup copy of the interpretation rules file. By default, this file is in the same location as the After Effects application.
3 Open the interpretation rules file in a text editor.
4 Modify the settings according to the instructions in the file.
Note: You must supply a four-character file-type code for each footage type or codec. If you don’t know the code for a file or codec in a project, press Alt (Windows) or Option (Mac OS) as you select the file in the Project panel. The file-type code and codec code (if the file is compressed) appear in the last line of the file description at the top of the Project panel.
5 Save interpretation rules.txt in the same folder as the After Effects application.