Video codecs supported within video file formats – Apple Final Cut Express HD User Manual
Page 985
Chapter 70
Learning About QuickTime
985
XII
Video Codecs Supported Within Video File Formats
A video codec is an algorithm for encoding video images in space (within a frame) and
time (across multiple frames) to compress the data requirements while still producing
an acceptable image. Not all codecs are supported by all file formats.
Uncompressed (None)
This isn’t really a codec, but a way of storing QuickTime movies with no compression at
all. Since applying compression generally results in video artifacts, no compression
guarantees the highest quality. Unfortunately, it also guarantees enormous file sizes,
and they will not play back in real time on most systems.
Uncompressed movies can have an alpha channel. Alpha channels define levels of
transparency in your movie and are useful if you’re delivering an effects shot for use in
someone else’s composition. For more information on alpha channels, see
“
Animation
The Animation codec was developed for computer-generated imagery, which often has
large areas of uniform color and little, if any, noise. It is a lossless codec, which means it
doesn’t degrade quality or add artifacts to your video when it applies compression. For
more information, see “
Video footage, which generally has more grain, noise, and variations of texture and
color than animated material, may not be compressed as much with the Animation
codec as with other methods. Because some lossless compression is better than none,
this codec is used more frequently than Uncompressed.
Note: Animation movies will not play back in real time on most systems. Animation
movies can also have an alpha channel.
DV Codecs
QuickTime supports a wide range of DV codecs, including DV NTSC and DV PAL,
DVCPRO 50, and DVCPRO HD. This allows you to natively capture, edit, and playback
footage from DV camcorders without first transcoding to another format.