Spice clients that are running directly on the host system have pratcially unlimited bandwidth so to reduce latency allow the user to configure the buffer_length to a lower value if desired.
While virt-viewer can not take advantage of this, the PureSpice [1] library used by Looking Glass [2] is able to produce and consume audio at these rates, combined with the merge request for spice-server [3] this allows for latencies close to realtime. [1] https://github.com/gnif/PureSpice [2] https://github.com/gnif/LookingGlass [3] https://gitlab.freedesktop.org/spice/spice/-/merge_requests/199 Signed-off-by: Geoffrey McRae <ge...@hostfission.com> --- audio/spiceaudio.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/audio/spiceaudio.c b/audio/spiceaudio.c index a8d370fe6f..0c44bbe836 100644 --- a/audio/spiceaudio.c +++ b/audio/spiceaudio.c @@ -76,7 +76,7 @@ static void *spice_audio_init(Audiodev *dev) if (!using_spice) { return NULL; } - return &spice_audio_init; + return dev; } static void spice_audio_fini (void *opaque) @@ -90,6 +90,8 @@ static int line_out_init(HWVoiceOut *hw, struct audsettings *as, void *drv_opaque) { SpiceVoiceOut *out = container_of (hw, SpiceVoiceOut, hw); + Audiodev *dev = (Audiodev *)drv_opaque; + struct audsettings settings; #if SPICE_INTERFACE_PLAYBACK_MAJOR > 1 || SPICE_INTERFACE_PLAYBACK_MINOR >= 3 @@ -102,7 +104,12 @@ static int line_out_init(HWVoiceOut *hw, struct audsettings *as, settings.endianness = AUDIO_HOST_ENDIANNESS; audio_pcm_init_info (&hw->info, &settings); - hw->samples = LINE_OUT_SAMPLES; + if (dev->u.none.out->has_buffer_length) { + hw->samples = audio_buffer_samples(dev->u.none.out, &settings, 10000); + } else { + hw->samples = LINE_OUT_SAMPLES; + } + out->active = 0; out->sin.base.sif = &playback_sif.base; @@ -199,6 +206,7 @@ static void line_out_volume(HWVoiceOut *hw, Volume *vol) static int line_in_init(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque) { SpiceVoiceIn *in = container_of (hw, SpiceVoiceIn, hw); + Audiodev *dev = (Audiodev *)drv_opaque; struct audsettings settings; #if SPICE_INTERFACE_RECORD_MAJOR > 2 || SPICE_INTERFACE_RECORD_MINOR >= 3 @@ -211,7 +219,12 @@ static int line_in_init(HWVoiceIn *hw, struct audsettings *as, void *drv_opaque) settings.endianness = AUDIO_HOST_ENDIANNESS; audio_pcm_init_info (&hw->info, &settings); - hw->samples = LINE_IN_SAMPLES; + if (dev->u.none.out->has_buffer_length) { + hw->samples = audio_buffer_samples(dev->u.none.in, &settings, 10000); + } else { + hw->samples = LINE_IN_SAMPLES; + } + in->active = 0; in->sin.base.sif = &record_sif.base; -- 2.30.2
