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2 Choose Layer Adobe Encore Assign To Subpicture [number] or Assign To Video Thumbnail.
Export a button for use in Adobe Encore 1 Open the composition that represents the button, and move the current-time indicator to the desired frame.
2 Choose Composition Save Frame As Photoshop Layers.
Creating an animated GIF movie An animated GIF file is a sequence of GIF images that plays as a movie. This format is commonly used for small, short, simple movies that play in web browsers.
To play an animated GIF file, the web browser first loads the entire file into memory and then plays it from memory (not from disk). To prevent excessive delays before playback begins, and to avoid using too much memory, an animated GIF should have a short duration and a low frame rate. Frame rates of 5 frames per second (or less) are recommended, unless the duration is very short (1 second or so).
When you render a movie to the animated GIF format, colors are dithered to an 8-bit palette (256 colors). Before rendering your final movie, render a test composition so that you can adjust colors if the results are not what you expect. You can create a color palette in Adobe Photoshop if the default Web Safe or System color palettes don’t give the results that you want.
A pixel in an animated GIF file is either completely opaque or completely transparent. When rendering an animated GIF movie, After Effects must convert the finely-graded alpha channel of the composition to this much simpler type of transparency. The transition between transparent and opaque areas is abrupt, and may not be desired for more subtle visual elements.
You render and export a movie as an animated GIF file using the render queue. Animated GIF is one of the formats available in the Format menu in the Output Module Settings dialog box.
See also“Basics of rendering and exporting” on page 587
Cross-platform project considerations After Effects project files are compatible with Mac OS and Windows operating systems, but some factors—mostly regarding the locations and naming of footage files and support files—can affect the ease of working with the same project across platforms.
File systems If you want to transfer a project that contains footage stored on a server from Mac OS to Windows, be sure to mount the server by using AppleShare (AFP). If you mount the volume in Mac OS by using Samba (SMB), After Effects can’t reestablish links to footage files stored on the server when you open the project on Windows.
If you are building cross-platform projects, it’s best if the full paths have the same names on Mac OS and Windows systems. If the footage and the project are on different volumes, make sure that the appropriate volume is mounted before opening the project and that network volume names are the same on both systems.
It’s best to store footage in the same folder as the project file or in another folder within that folder. Here’s a sample
/newproject/project_file.aep /newproject/source/footage1.psd /newproject/source/footage2.avi You can then copy the newproject folder in its entirety across platforms, and After Effects will properly locate all of the footage.
Note: Use the Collect Files feature to gather copies of all the files in a project into a single folder. You can then move the folder containing the copied project to the other platform. See “Collect files in one location” on page 594.
File-naming conventions Name your footage and project files with the appropriate file-name extensions, such as.mov for QuickTime movies and.aep for After Effects projects. Don’t use high-ASCII or other extended characters in file names to be used crossplatform. If files will be used on the web, be sure that file names adhere to applicable conventions for extensions and paths.
Supported file types Some file types are supported on one platform but not another. See “Supported import formats” on page 48 and “Supported output formats” on page 588.
Resources Ensure that all fonts, effects, codecs, and other resources are available on both systems. Such resources are often plug-ins.
If you use a native After Effects effect in a project on one operating system, the effect will still work on the other operating system to which you’ve transferred your project. However, some third-party effects and other third-party plug-ins may not continue to operate, even if you have versions of these plug-ins on the target system. In such cases, you may need to reapply some third-party effects.
See also “About plug-ins” on page 44 “Work with fonts” on page 278
After Effects renders each frame of a composition one layer at a time. For this reason, the memory requirement of each individual layer is more important than the duration of the composition or the number of layers in the composition. The memory requirement for a composition is equivalent to the memory requirement for the most memoryintensive single layer in the composition. For example, it generally takes less memory to render 30 layers at NTSC resolution than 2 layers at motion-picture film resolution.
Note: If the Render Multiple Frames Simultaneously option is selected, each background copy of the After Effects application renders one frame at a time.
When a layer includes a composition as a source item, everything in that composition must be rendered before the next layer is rendered.
The memory requirements of a layer increase under the following circumstances:
• Using a larger source image
• Enabling color management
• Adding a mask
• Adding per-character 3D properties
• Using certain blending modes, layer styles, or effects, especially those involving multiple layers
• Applying certain output options, such as 3:2 pulldown, cropping, and stretching
• Adding shadows or depth-of-field effects If you have no problems viewing each frame of a full-resolution, best-quality preview of a composition, then you have enough memory to render the composition. Rendering a composition into a movie takes no more memory than displaying it on-screen with the same settings.
Occasionally, After Effects may display an alert message indicating that it requires more memory to display or render a composition. If you receive an out-of-memory alert, free memory or reduce the memory requirements of the most memory-intensive layers, and then try again.
Free memory immediately with one or more of the commands in the Edit Purge menu.
The operating system imposes certain limits on the amount of memory that an application can use. After Effects on the Mac OS X operating system can use up to 3.5 GB of RAM, although only about 3GB is actually available to the foreground application, because Mac OS X uses approximately 500MB to load the user interface libraries. After Effects on 32-bit Windows operating systems can use up to 3 GB of RAM; however, to use more than 2 GB in After Effects, you must configure Windows XP or Windows Vista appropriately. (For details, see the Microsoft website or Jonas Hummelstrand’s website: www.adobe.com/go/learn_ae_jonaswindows3gb.) After Effects on 64-bit Windows operating systems can use up to 4 GB of RAM with no special configuration.
Note: These numbers are for each After Effects process. The background processes used to render multiple frames simultaneously can each use the amount of RAM mentioned above. (See “Render multiple frames simultaneously” on page 40.) Because video is typically compressed during encoding when you render to final output, you can’t just multiply the amount of memory required for a single frame by the frame rate and composition duration to determine the amount of disk space needed to store your final output movie. However, such a calculation can give you a rough idea of the maximum storage space you might need. For example, one second of uncompressed standard-definition 8-bpc video requires approximately 40 megabytes (MB). A feature-length movie at that data rate would require more than 200 GB to store. Even with DV compression, which reduces file size to 3.6 MB per second of video, this translates to more than 20 GB for a typical feature-length movie. It is not unusual for a feature-film project—with its higher color bit depth and greater frame size—to require terabytes of storage for footage and rendered output movies.
RAM and disk caches As you work on a composition, After Effects temporarily stores some rendered frames and source images in RAM, so that previewing and editing can occur more quickly. After Effects does not cache frames that require little time to render. Frames remain uncompressed in the cache. You can control how After Effects stores images by setting imagecaching preferences.
After Effects also caches at the footage and layer level for faster previews; layers that have been modified are rendered during the preview, and unmodified layers are displayed from the cache.
Blue bars in the Timeline panel mark frames that are cached to disk. Green bars mark frames that are cached to RAM.
Choose Show Cache Indicators from the Timeline panel menu to turn the cache indicators on and off. Showing the cache indicactors decreases performance slightly.
When the cache is full, any new frame added to the cache replaces a frame cached earlier. When After Effects renders frames for RAM previews, it stops adding frames to the cache when the cache is full and begins playing only the frames that could fit in the cache. The disk cache is not used for RAM previews. If disk caching is enabled, After Effects can store rendered items to your hard disk when the RAM cache is full during standard previews.
The RAM cache and disk cache are automatically purged when you quit After Effects.
To purge the RAM cache and disk cache, choose Edit Purge Image Caches.
rendering a frame, memory usage drops back down to, at most, the amount set by the Maximum RAM Cache Size preference.
You can specify values over 100% (where 100% equals the amount of physical RAM you have installed) because virtual memory uses hard-disk space. Values over 200% are not recommended. The default value is 120%.
Maximum RAM Cache Size The maximum amount of memory that After Effects will use when not rendering a frame. This memory includes image caches, the application itself, memory reserved for GPU acceleration, and so on.
This setting determines the amount of memory available for (and therefore the duration of) RAM previews.
If you set this value to greater than the default value of 60%, you may encounter problems such as decreased performance when switching from one application to another or increased frequency of errors that say that After Effects is unable to create an image buffer. Like a hard disk, your address space can become fragmented; if you have Maximum RAM Cache Size set too high, the memory may become too fragmented to store the next rendered frame.
By lowering the cache percentage, you reduce the chance of fragmentation. Set this value above 60% only if necessary.
You should not set this value above 90%.
When you have enabled multiprocessing, the amount of RAM available to background processes is affected by the amount of RAM reserved for the foreground process. Decreasing Maximum RAM Cache Size can free memory for background processes. (See “Render multiple frames simultaneously” on page 40.) Enable Disk Cache Moves rendered frames to your hard disk when the RAM cache is full. After Effects will only use the disk cache to store a frame if it’s faster to retrieve a frame from the cache than to re-render the frame. Select a folder to contain your cache, and click OK (Windows) or Choose (Mac OS). For the best performance, select a folder that’s on a different physical hard disk than your source footage. If possible, the folder should be on a hard disk that uses a different drive controller than the disk that contains your source footage. The disk cache folder can’t be the hard disk’s root folder.
Maximum Disk Cache Size Specifies the number of megabytes of hard disk space to use. This should be at least 2 gigabytes (GB).
Prevent DLL Address Space Fragmentation (Windows only) Select this option to give After Effects access to more contiguous memory on a computer with a large amount of RAM. This option may be incompatible with some OpenGL drivers, which can cause a crash when the application starts. If such a crash occurs, the option will become unchecked automatically to prevent further crashes when you start After Effects.
For information on working with large images and avoiding the error message that says that After Effects ”could not create image buffer”, see Jonas Hummelstrand’s website: www.adobe.com/go/learn_ae_jonasimagebuffererror.
If background processes are used for rendering, then the main foreground application is not also used for rendering.
This means that creating background processes only adds to the total number of processes used for rendering if there are enough resources for at least two background processes to run.
1 Choose Edit Preferences Multiprocessing (Windows) or After Effects Preferences Multiprocessing (Mac OS).
2 Select Render Multiple Frames Simultaneously.
The bottom of the Preferences dialog box shows how many additional processors (in addition to the worst-case scenario of one processor) will be used at the current settings. To increase the number of background processes that can run, decrease Maximum RAM Cache Size or install more RAM.
Selecting the Render Multiple Frames Simultaneously option does not immediately start the background processes.
The background processes start when the first render operation (for a RAM preview or for final output) is initiated after the option is selected. The background processes continue running until the option is deselected.
Important: You may experience a small delay when the background processes start for the first time, when the first render operation occurs. A message in the Info panel indicates when the background processes are initializing.
Deselecting Render Multiple Frame Simultaneously stops the background processes; reselecting the option causes the same delay when the next render operation begins.