The monitoring deduplication was previously checking at each audio tick
the whole audio tree for Audio Output Capture (AOC) devices used for
monitoring. The profiling did not show any big impact on the audio
callback. But due to reports of a significant slowdown for scenes with
numerous audio sources, we have moved the check on AOC from the audio
thread to the UI thread.
So we implemented obs_source_audio_output_capture_device_changed which
is triggered whenever:
- a monitoring device is changed in Settings > Audio,
- an Audio Output Capture source changes its device or on startup.
This function compares the AOC device with the monitoring device in UI
thread. If they are identical, a signal is sent to the audio thread to
add an audio task updating the AOC duplicating source pointer at the end
of an audio tick.
This triggers monitoring deduplication if the ptr is not NULL.
The calls in the AOC are implemented in next commits.
The rest of the logic in obs-audio.c is the same except on one count,
which is that we check against the muted state of the AOC rather than
its user_muted; with the new logic, muted works better.
Signed-off-by: pkv <pkv@obsproject.com>
91917f8120