Commit b2633199 authored by Rémi Denis-Courmont's avatar Rémi Denis-Courmont
Browse files

PulseAudio: increase prebuffering

This should fix practically glitches. The resulting A/V synchronization
is not too bad for me inspite of the long buffer (1/2 seconds).
Your mileage may vary.
parent c0e7149a
......@@ -171,23 +171,24 @@ static void Play(aout_instance_t *aout)
/* This function should be called by the LibVLC core a header of time,
* but not more than AOUT_MAX_PREPARE. The PulseAudio latency should be
* shorter than that (though it might not be the case with some evil piece
* of audio output hardware). So we need to prepend the buffer with zeroes
* to keep audio and video in sync. */
* of audio output hardware). So we may need to trigger playback early,
* (that is to say, short cut the PulseAudio prebuffering). Otherwise,
* audio and video may be out of synchronization. */
pa_usec_t latency;
int negative;
if (pa_stream_get_latency(s, &latency, &negative) < 0) {
/* Especially at start of stream, latency may not be known (yet). */
if (pa_context_errno(sys->context) != PA_ERR_NODATA)
error(aout, "cannot determine latency", sys->context);
latency = 0;
mtime_t gap = aout_FifoFirstDate(aout, &aout->output.fifo) - mdate()
} else {
mtime_t gap = aout_FifoFirstDate(aout, &aout->output.fifo) - mdate()
- latency;
msg_Dbg(aout, "buffer too early (%"PRId64" us)", gap);
else if (latency != 0 && gap < -AOUT_PTS_TOLERANCE)
msg_Err(aout, "buffer too late (%"PRId64" us)", -gap);
msg_Dbg(aout, "buffer too early (%"PRId64" us)", gap);
else if (gap < -AOUT_PTS_TOLERANCE)
msg_Err(aout, "buffer too late (%"PRId64" us)", -gap);
#if 0 /* Fault injector to test underrun recovery */
static unsigned u = 0;
......@@ -346,7 +347,7 @@ static int Open(vlc_object_t *obj)
/* no point in larger buffers on PA side than VLC */
attr.maxlength = -1;
attr.tlength = byterate * AOUT_MAX_ADVANCE_TIME / CLOCK_FREQ;
attr.prebuf = byterate * AOUT_MIN_PREPARE_TIME / CLOCK_FREQ;
attr.prebuf = byterate * AOUT_MAX_PREPARE_TIME / CLOCK_FREQ;
attr.minreq = -1;
attr.fragsize = 0; /* not used for output */
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