If snd-aloop device is on playback side, the required sync mode is
PLAYSHIFT. That means Loopback ctl elem "PCM Rate Shift 100000" of the
corresponding capture side of the Loopback pipe must be controlled (by
a reciprocal).
ASCII name of the playback rate shift ctl elem is specified with newly
added option -x/--prateshift, e.g.:
-P hw:Loopback,0 -S playshift \
-x iface=PCM,name='PCM Rate Shift 100000',device=1
Signed-off-by: Pavel Hofman <pavel.hofman@ivitera.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
In Linux 5.14, a new feedback mechanism for USB Audio
Gadget is introduced (commit e89bb428), along with a
new control element "Capture Pitch 1000000". This patch
adds support for this feature. Note that this property
seems to be the reverse of PCM Rate Shift, so we have
to take reciprocal of pitch.
Signed-off-by: Yunhao Tian <t123yh@outlook.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
- added -W/--wake option to reduce poll time
- another try to fix the avail_min parameter for playback
- fixed initial silence fill
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
In some cases it might be usefull to specify another CTL device names.
Add -X/--pctl and -Y/--cctl options.
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
- added workaround for alsa-lib (pthread configuration parsing issue) -
the workaround must be activated manually using ('--workaround serialopen')
- fixed avail_min initialization (caused high CPU usage or xruns)
- fixed shared buffer initialization (both capture and playback buffers
must have equal number of samples in this config)
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
alsaloop allows create a PCM loopback between a PCM capture device
and a PCM playback device.
alsaloop supports multiple soundcards, adaptive clock synchronization,
adaptive rate resampling using the samplerate library (if available in
the system). Also, mixer controls can be redirected from one card to
another (for example Master and PCM).
Signed-off-by: Jaroslav Kysela <perex@perex.cz>