Mixing Footage with Different Codecs
A codec, or compressor, is the algorithm used to compress video to a smaller size and
then decode the video for playback. A sequence clip whose codec doesn’t match the
sequence codec can be played back in real time as long as the following is true:
 Final Cut Pro has real-time support for both the clip and sequence codecs.
 Your computer has the processing power and disk speed to play back the clip codec
in real time.
When playing back video in the Viewer and Canvas, or via Digital Cinema Desktop
Preview, Final Cut Pro decompresses each sequence clip’s codec and shows the
decoded video on your display. However, when rendering and outputting, each
sequence clip is also recompressed into the selected sequence codec, requiring
additional processing power. Because rendering is not a real-time process, this is not an
issue, but for real-time playback to an external video device, mixed codecs can add
additional processing overhead. For more information, see “
External Monitoring and
Output
” on page 697.
For more information about rendering mixed-format sequences, see “
Rendering
Mixed-Format Sequences
” on page 697.