Apple Compressor 3 - Manual (Page 168)

Important: For maximum compatibility with HD DVD players, avoid setting the maximum
bit rate above 18 Mbps.
You must keep the total of both average and maximum audio and video bit rates under
30 Mbps, the maximum guaranteed transfer rate from high definition DVD players. Because
DVD-compatible audio formats are constant bit rate (CBR), there is no maximum audio
bit rate to worry about.
For example, if you are using AIFF audio at 1.5 Mbps, you should keep both the average
and maximum video bit rates for high definition DVDs under 28.5 Mbps. Typically, your
average bit rate will be lower than this (from 7 Mbps to 15 Mbps). However, your maximum
bit rate must also stay under this number. The 28.0 Mbps maximum bit rate is
recommended to provide an extra margin for error (for example, to accommodate subtitle
streams).
If you are using one of the DVD-compatible compressed audio formats such as Dolby
Digital or MPEG-1/Layer-2, your audio bit rate may be as low as 0.2 Mbps to 0.4 Mbps, in
which case you can set your maximum bit rate about 1 Mbps higher. As a general rule,
set your maximum bit rate at least 1 Mbps higher than your average bit rate, to allow for
bit-rate variability in achieving the goal of constant quality.
H.264 Workflows for DVD
The efficiency and quality of H.264 creates a number of options for DVD producers.
• Because H.264 can deliver high definition (HD) video at standard definition (SD) bit
rates, you can get 90 minutes of HD content on a regular DVD-5 disc, which is playable
on the new HD DVD players.
• Video resolutions supported by SD DVDs are also supported by HD DVDs. This means
that a high definition DVD can use an HD video resolution file for its main content, such
as a feature film, and then use SD video resolution files for additional features like
trailers and a “making of” documentary.
168 Chapter 13 Creating H.264 for DVD Studio Pro Output Files