Apple Final Cut Pro 5 - Manual (Page 1585)

234 Part III Output
Apple M-JPEG
There are two Apple M-JPEG codecs, M-JPEG A and M-JPEG B. These are variable data
rate codecs similar to the ones used by video capture cards. If you need to deliver more
heavily compressed material to keep files small, consider these codecs. M-JPEG is a
“lossy” codec (meaning visual information is permanently removed from the video
frames) and will result in artifacts in your video. The severity of these artifacts depends
on the data rate you choose.
Several video interface cards on the market can play back either M-JPEG A or M-JPEG B
in real time without rerendering the material, or, at most, doing minimal rerendering.
This makes file interchange very fast. Before you use either M-JPEG A or B, consult the
manufacturer of the capture card you’re using to find out which one you should use.
Note: Apple M-JPEG movies cannot have alpha channels.
JPEG
JPEG is similar to M-JPEG, except that the compression artifacts can be less severe at
similar data rates. JPEG movies may play back in real time on your system, depending
on your system’s capabilities and the data rate of the movie.
Note: JPEG movies cannot have alpha channels.
Third-Party Codecs
There are several manufacturers of video-editing solutions, most of whom use different
variations of the M-JPEG codec. Many make software-only QuickTime codecs that you
can install on your system, enabling you to play back movies with little or no
rerendering. For more information, contact the manufacturer of the editing system.
Note: Most third-party codecs cannot have alpha channels.