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357 ADOBE PREMIERE 5.0
User Guide
Cinepak
Useful for compressing 24-bit video intended for CD-ROM discs or for downloadable
Web video files. This codec attains higher compression ratios and faster playback speeds
than the Video codec. You can set the data rate for playback; picture quality drops more
noticeably at data rates below 30 KBps. Cinepak is asymmetrical—it decompresses quickly,
but compression is slow enough to make it impractical for editing. For best results, use
Cinepak only for exporting the final version of a video file.
Sorenson Video Useful for compressing 24-bit video intended for CD-ROM discs or for
downloadable World Wide Web video files. Similar to Cinepak, this newer codec is designed
for high quality at data rates under 200 KBps. This codec is capable of better picture quality and
smaller files than Cinepak. It requires more compression time than Cinepak, so it is suitable for
final export but not for editing. It supports
temporal scalability , which lets a movie exported for
a high-end computer play back smoothly on a low-end computer.
Planar RGB A lossless codec effective for frames that use large areas of solid colors, such as
animation. It uses run-length encoding and is an alternative to the Animation codec.
QuickTime audio codecs
When editing, the following software codecs for audio are provided if you choose QuickTime
from the Editing Mode menu in the General Settings panel of the Project Settings dialog box.
When exporting, the following software codecs are provided if you choose QuickTime from the
File Type menu in the General Settings panel of the Export Movie Settings dialog box.
The audio codecs themselves appear in the Type menu in the Audio Settings panel of either
dialog box. Some of the codecs below use a specific compression ratio (such as 2:1). When they
do, the compression ratio is listed after the codec name. In general, use a codec specifically
designed for the type of audio in your program, such as speech, music, or multimedia. Avoid
codecs intended for telephony unless your audio is almost exclusively speech to be delivered
over low-bit-rate media such as the Web.
µ
Law 2:1 Useful for exchanging audio with applications on platforms (such as many UNIX
workstations) where
µ
Law is a standard audio format .
µ
Law is used for digital telephony in
North America and Japan. (The first letter of the codec name is a Greek letter pronounced Mu.)
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