Apple Compressor (4.0) - Manual (Page 101)

Chapter 5 Custom settings and output formats 101
QuickTime audio sample sizes and rates
If you have the disk space and bandwidth, it’s best to leave your audio uncompressed.
Uncompressed audio normally uses 8-bit (phone quality) or 16-bit (CD quality) samples. Compressor
supports up to 64 bits per sample floating point and a maximum sample rate of 192 kHz.
Choosing an audio codec for distribution
MPEG-4 Audio (AAC) is a good general-purpose audio delivery codec and is compatible with a
wide variety of playback devices. For slower computers, less-compressed formats, such as IMA,
or completely uncompressed formats, such as AIFF, may be better choices, because they are less
processor intensive, thus allowing the computer to focus on the more challenging video stream.
Create AIFF settings
When you choose the AIFF output file format as your output format, you can only create audio
settings (because AIFF is an audio-only format). If you want to add an audio codec to your AIFF
preset, you need to open the Sound Settings dialog and choose your audio codec settings
from there.
Create an AIFF audio codec setting
1 In the Settings tab, select a setting or create a new setting by choosing AIFF from the Create a
New Setting (+) pop-up menu.
2 Choose AIFF from the File Format pop-up menu in the Encoder pane of the Inspector window.
QuickTime AIFF
Summary table
Click to open the Sound
Settings dialog.
Extension field
Choose AIFF.
Note: The Extension field displays the AIFF file extension (.aiff) automatically after the AIFF
output format is chosen from the File Format pop-up menu or the Create a New Setting (+)
pop-up menu in the Settings tab. Don’t alter this field.
The Allow Job Segmenting checkbox allows you to turn off job segmenting. Because job
segmenting isn’t used for audio-only encodes, this checkbox is not available with the AIFF file
format. For more information, see
Job segmenting and two-pass or multi-pass encoding on
page 249.