Alternative Architecture Mode (Alt_Arch) - XMOS VocalFusion XVF3510 User Manual

COMMAND
SET_INCREMENT_GAIN_STEPSIZE_CH0_
AGC
SET_INCREMENT_GAIN_STEPSIZE_CH1_
AGC
GET_INCREMENT_GAIN_STEPSIZE_CH0_
AGC
GET_INCREMENT_GAIN_STEPSIZE_CH1_
AGC
SET_DECCREMENT_GAIN_STEPSIZE_CH
0_AGC
SET_DECREMENT_GAIN_STEPSIZE_CH1
_AGC
GET_DECREMENT_GAIN_STEPSIZE_CH0
_AGC
GET_DECREMENT_GAIN_STEPSIZE_CH1
_AGC

4.5.7. ALTERNATIVE ARCHITECTURE MODE (ALT_ARCH)

The Alternative Architecture mode, when enabled, improves Echo Cancellation performance in
reverberate environments. It operates by re-configuring the audio pipeline by switching out either the
AEC or the IC, depending on the energy in the AEC reference signal, to recover resources to be used
to increase the specification of the remaining pipeline.
The two audio pipeline configurations are summarised below:
}
ALT_ARCH disabled ALWAYS apply echo-cancelling AND interference cancelling; or
}
ALT_ARCH enabled apply ONLY echo-cancelling when a reference signal is available,
otherwise ONLY apply interference cancelling
The figure below expands the implementation details of the alternative mode switching. Multiplexers
permit the AEC and/or the IC to be bypassed. When the IC is bypassed, only a single channel from
the AEC is used, allowing it to be reconfigured, extending the filters to support a longer tail length. An
internal module which collects statistics about the reference is used to dynamically control these
multiplexers and memory allocation during runtime.
NOTE: Manually bypassing the IC using the Control Interface does not apply the memory reallocation.
The figure below highlights the audio signal path when the Alternative Architecture is disabled (ie.
standard operation).
XM-014232-PC
TYPE VALUE DESCRIPTION
Set the rate at which the gain increases. This value
Q16.16 [1..32767] is applied on a per-frame basis when voice content
is detected.
Set the rate at which the gain decreases. This value
Q16.16 [0..1] is applied on a per-frame basis when voice content
is detected.
60