Manual

Table Of Contents
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5.1.1.1 HD-AAC 16/24-bit modes
The HD-AAC codec has a 16-bit mode that is selectable in the
CODEC & SETTINGS window by selecting CD resolution
rather than 24-bit HD resolution
For online HD-AAC Operation there are three volatile buttons
that appear at the bottom of the Codec Settings window for an
HD-AAC codec (see right):
1. A button to enable dithering at whichever resolution is
selected by the other buttons.
2. A CD button to select 16-bit resolution
3. An HD button to select 24-bit resolution.
Together, these buttons allow the selection of how much resolution to use for the HD-AAC
encoding, and whether to dither before truncation to that resolution.
These settings are reflected in the bit meter operation when viewing HD-AAC codecs, and
they are reflected by all HD-AAC codecs during online DSP. The settings are saved into
presets and project settings.
During offline encoding, the resolution used for the writing follows the PCM width of the
source file. You cannot reduce the resolution as part of the offline HD-AAC encoding
process.
For offline decoding, the HD-AAC decoder detects the original source file PCM width that
was used by the HD-AAC encoder. There is also a general-purpose 16/24-bit output file
selector on the OFFLINE DECODE tab.
If the switch is set to 24 bits, the output file PCM width will follow the original file PCM
width: 16 -> 16 or 24 -> 24. This is the recommended (and default) setting. If the switch is
set to 16 bits, then the decoded output PCM width will always be 16 bits.