Chapter 15: memory, storage, and performance, Memory and storage, Memory (ram) usage and storage – Adobe After Effects CS4 User Manual
Page 638: Memory (ram) requirements for rendering
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Last updated 12/21/2009
Chapter 15: Memory, storage, and
performance
Memory and storage
Memory (RAM) usage and storage
Factors that influence memory (RAM) available to After Effects
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 3 GB is actually available to the
foreground application, because Mac OS X uses approximately 500 MB 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,
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 “
Memory & Multiprocessing preferences
Memory (RAM) requirements for rendering
Memory requirements for rendering (either for previews or for final output) increase with the resolution of the
composition frame and the memory requirement of the most memory-intensive layer in the composition.
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 memory-intensive
single layer in the composition. For example, it generally takes less memory to render 30 layers at NTSC dimensions
than 2 layers at motion-picture film dimensions.
If you have no problems previewing each frame of a full-resolution, best-quality preview of a composition, then you
have enough RAM to render the composition for final output.
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 when using 3D layers
After Effects requires a contiguous block of memory to store each frame; it cannot store a frame in pieces in fragmented
memory.