What Is Rendering?
Any time Final Cut Pro must perform more calculations than your computer can handle
in real time, you need to render. Rendering is the process of creating temporary video
and audio render files for segments of your sequence that Final Cut Pro cannot play in
real time. When you render a segment of your sequence, Final Cut Pro substitutes a
render file for the segment during playback. Render status bars above the ruler in the
Timeline indicate which sections can play back in real time and which segments
require rendering.
Because rendering takes time away from the editing process, the goal is to render as
little as possible. For more information about real-time playback, see Chapter 28, “
Using
RT Extreme
,” on page 617.
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Part IV
Real Time and Rendering
Rendering is generally required for:
 The use of filters, transitions, generators, or any combination of effects that exceeds
your computer’s real-time playback capabilities.
 High-quality final output. Real-time effects that play back at preview quality must
ultimately be rendered for high-quality video output.
 Video clips using codecs that Final Cut Pro can’t play in real time
 Multiple audio tracks that exceed your real-time playback limit
 Clips with audio effects that require too much processing power
 Some nested sequences, which can include layered Photoshop files