mirror of https://github.com/mpv-player/mpv
f974382ca0
A figure from pipewire documentation:
```
stream time domain graph time domain
/-----------------------\/-----------------------------\
queue +-+ +-+ +-----------+ +--------+
----> | | | |->| converter | -> graph -> | kernel | -> speaker
<---- +-+ +-+ +-----------+ +--------+
dequeue buffers \-------------------/\--------/
graph internal
latency latency
\--------/\-------------/\-----------------------------/
queued buffered delay
```
We calculate `end_time` in the following steps:
1. get current timestamp in mpv
```
int64_t end_time = mp_time_ns();
```
2. add duration of samples to enqueue
```
end_time += MP_TIME_S_TO_NS(nframes) / ao->samplerate;
```
3. add delay of the pipewire graph
```
end_time += MP_TIME_S_TO_NS(time.delay) * time.rate.num / time.rate.denom;
```
4. add duration of queued and buffered samples.
```
end_time += MP_TIME_S_TO_NS(time.queued) / ao->samplerate;
end_time += MP_TIME_S_TO_NS(time.buffered) / ao->samplerate;
```
New in this commit. `time.queued` is usually zero as `SPA_PARAM_BUFFERS_buffers`
is default to 1; however it is not always.
`time.buffered` is non-zero if there is a resampler involved.
5. add elapsed duration from when `time` is captured
```
end_time -= pw_stream_get_nsec(p->stream) - time.now;
```
New in this commit. `time` is captured at `time.now`.
From then, time has passed so we need to exclude the elapsed time,
by calculating the diff of `pw_stream_get_nsec()` and `time.now`.
|
||
|---|---|---|
| .. | ||
| ao.c | ||
| ao.h | ||
| ao_alsa.c | ||
| ao_audiotrack.c | ||
| ao_audiounit.m | ||
| ao_avfoundation.m | ||
| ao_coreaudio.c | ||
| ao_coreaudio_chmap.c | ||
| ao_coreaudio_chmap.h | ||
| ao_coreaudio_exclusive.c | ||
| ao_coreaudio_properties.c | ||
| ao_coreaudio_properties.h | ||
| ao_coreaudio_utils.c | ||
| ao_coreaudio_utils.h | ||
| ao_jack.c | ||
| ao_lavc.c | ||
| ao_null.c | ||
| ao_openal.c | ||
| ao_opensles.c | ||
| ao_oss.c | ||
| ao_pcm.c | ||
| ao_pipewire.c | ||
| ao_pulse.c | ||
| ao_sdl.c | ||
| ao_sndio.c | ||
| ao_wasapi.c | ||
| ao_wasapi.h | ||
| ao_wasapi_changenotify.c | ||
| ao_wasapi_utils.c | ||
| buffer.c | ||
| internal.h | ||