Factors That Affect Real-Time Performance
Many components of your computer affect its real-time performance:
Â Computer processor speed and type: The faster your computer processor is, the more
real-time effects Final Cut Pro can perform. The type of processor can also make a
difference. For example, a G5 processor is more powerful than a G4 processor, and a
Core 2 Duo processor is more powerful than a Core Duo processor.
Â Multiple processors: Computers with more than one processor have significant
real-time performance advantages over single-processor computers.
Â Graphics card speed and memory: Many video filters in Final Cut Pro use your computer’s
graphics card to process effects, leaving the computer processor free to perform other
tasks. A faster graphics card with more RAM allows more real-time playback.
Â Level 2 and Level 3 processor cache: The sizes of a computer processor’s level 2 and 3
caches affect its real-time playback capabilities. The larger these caches are, the more
real-time performance is available.
Â RAM: The more RAM you have available in your computer, the more potential
real-time performance your computer has.
Real Time and Rendering
Â Memory bus speed: Computers with a faster memory bus allow better real-time
performance because data can be sent more quickly between RAM and the
Â Hard disk speed: The faster your hard disk can read data, the more video data
Final Cut Pro can access in real time. With some video formats, such as
uncompressed video, hard disks may not be able to keep up with the video data rate,
making real-time playback impossible. Multiclips and multiple video layers require
many video streams to play back simultaneously. A faster hard disk allows more
streams to play back simultaneously in real time.
Â Codec: Not all codecs are supported by RT Extreme, but the most commonly used
ones are. Some codecs require more processing power and RAM to play back than
others. For example, the long-GOP MPEG-2 compression used by HDV requires more
RAM and processing power to decompress than I-frame-only codecs such as DV. For
more information, see “
Supported Real-Time Playback Codecs
” on page 638.
Â External video monitoring: Enabling output via FireWire or other video interfaces
requires additional processing power and may limit the number of effects you can
play back in real time. For more information, see Volume I, Chapter 14, “External