Manual

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In particular, the HD-AAC lossless codec creates a heavy CPU load. High sample rates
exacerbate this situation; for example, without a powerful CPU, the HD-AAC codec might
cause a prohibitively high CPU load at 192kHz.
All codecs that are added to the CODEC LIST are always active, in order to report
accurately the NMR signal and potential overload state. This is irrespective of which codec is
selected for monitoring. Remember that this requires both encoding and decoding of the
signal in real time. Thus it is possible to have dropouts with an underpowered CPU if several
highly intensive codecs are active simultaneously.
Online recording will add to the CPU activity (and file-handling activity).
Offline encoding and decoding are CPU-bound, not real time bound.
Graphical Screen: The graphical area is not CPU-intensive, and should not cause
performance problems even on older CPUs.
10.3.3 Internal Buffer Sizes
Additionally, for most codecs, the plug-in uses internal buffer sizes of 1024 for up to 48kHz
operation; 2048 for greater than 48kHz up to 96kHz operation; and 4096 for sample rates
higher than 96kHz. We recommend that the buffer sizes of the sound card, and thus of the
host application, are set to match these figures.
Buffer sizes for the HE-AAC and HE-AACv2 codecs are twice these figures (so 2048 for up
to 48kHz operation; 4096 for greater than 48kHz up to 96kHz operation; and 8192 for sample
rates higher than 96kHz).
If the buffer sizes are not matched, there will be an inefficiency in the data transfer, and in
some applications this leads to uneven CPU behaviour.
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