diff options
| author | Vito Caputo <vcaputo@pengaru.com> | 2020-11-13 21:58:22 -0800 |
|---|---|---|
| committer | Vito Caputo <vcaputo@pengaru.com> | 2020-11-13 21:58:22 -0800 |
| commit | 2341ddfcd96f72cc4ee2c4f1e091ff2306caf62a (patch) | |
| tree | e187d80e74565d643b53159739a15b99be97b120 /src/rmd_opendev.c | |
| parent | b9e0c2ce4c0e8a93f6227bc71bcab5292389b1b4 (diff) | |
opendev: bump granularity of audio capture periods
This only applies to ALSA, but the av-sync precision is entirely
dependent on the granularity of what ALSA refers to as "periods".
The pdata->avd delay is decremented by the audio capture in
period aligned steps, meaning the smallest decrement it can
possibly do is the period size. Between these period sized
intervals, rmdGetFrames kind of flies blind if the FPS is high
enough for frametime to be substantially smaller than the period
time.
A smaller period does increase the ALSA capture overhead,
basically increasing the number of times ALSA returns data to
userspace, kind of like a higher interrupt rate. But it seems
negligible for a modern system.
Diffstat (limited to 'src/rmd_opendev.c')
| -rw-r--r-- | src/rmd_opendev.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/rmd_opendev.c b/src/rmd_opendev.c index c8460d9..e5347a3 100644 --- a/src/rmd_opendev.c +++ b/src/rmd_opendev.c @@ -52,7 +52,7 @@ snd_pcm_t *rmdOpenDev( const char *pcm_dev, { snd_pcm_t *mhandle; snd_pcm_hw_params_t *hwparams; - unsigned int periods = 2; + unsigned int periods = 4; unsigned int exactrate = *frequency; // The compiler might warn us because the expansion starts with |