Beth Cataldo, March 27, 2007
| Beth Cataldo, March 27, 2007 |
Encoding Audio Streams
DVD Studio Pro imports several audio formats, including MPEG-1, AIFF, WAV, PCM,
Dolby
Digital AC-3 formats
and DTS
(Digital Theater Systems). However, Dolby Digital AC-3 is
the most common format because it is high quality but also takes up much less
room on
the disc than those other formats. Audio sucks up bandwidth, leaving little
room for
video if it’s left uncompressed. For
this reason, Compressor allows you to encode your
audio files into smaller AC-3 streams.
Compressor
accepts AIFF, WAV, QuickTime and SDII files that have a sampling rate
of 48kHz.
CD audio is sampled at 44Khz so you will need to convert it with QuickTime Pro
before you bring it into Compressor.
Depending on the format, a file
can contain a single channel (mono), dual channels
(stereo), or multiple channels. Compressor supports Dolby Digital Professional
in all
these configurations.
Sound files intended for Dolby Digital Professional encoding must conform to
the
following rules:
• All source files should be the same length. (If they are not, Compressor
sets the
length of the AC-3 stream to match the length of the longest file.)
• All files must have a 48 kHz sample rate (as required for DVD).
Note: Compressor 2 can support any kind of source files that
contain surround sound
and high resolution audio up to 64 bits per sample (floating point) and sample
rates up
to192 kHz.
Source: Apple's Compressor 2 User Manual