[vlc-commits] [Git][videolan/vlc][master] 4 commits: aaudio: simplify silence calculation

[Jean-Baptiste Kempf (@jbk)]

Jean-Baptiste Kempf pushed to branch master at VideoLAN / VLC


Commits:
44df0486 by Thomas Guillem at 2022-11-26T11:45:56+00:00
aaudio: simplify silence calculation

- - - - -
1de63445 by Thomas Guillem at 2022-11-26T11:45:56+00:00
aaudio: reset timing counter only in case of success

That way, GetFrameTimestampLocked() will be called again just after a
failure (until it succeed, then every 1 seconds).

- - - - -
5d809b36 by Thomas Guillem at 2022-11-26T11:45:56+00:00
aaudio: handle 0 pos_frames

0 is possible and will happen with the next commit.
Never seen a negative value though.

- - - - -
84140d6b by Thomas Guillem at 2022-11-26T11:45:56+00:00
aaudio: fetch timestamp immediately

And not after 1 second of playback.

- - - - -


1 changed file:

- modules/audio_output/android/aaudio.c


Changes:

=====================================
modules/audio_output/android/aaudio.c
=====================================
@@ -329,11 +329,9 @@ GetFrameTimestampLocked(aout_stream_t *stream, int64_t *pos_frames,
     aaudio_result_t result =
             vt.AAudioStream_getTimestamp(sys->as, CLOCK_MONOTONIC,
                                          pos_frames, &time_ns);
-    if (result != AAUDIO_OK)
+    if (result != AAUDIO_OK || *pos_frames <= 0)
         return VLC_EGENERIC;
 
-    assert(*pos_frames > 0);
-
     *frame_time_us = VLC_TICK_FROM_NS(time_ns);
     return VLC_SUCCESS;
 }
@@ -359,11 +357,9 @@ DataCallback(AAudioStream *as, void *user, void *data_, int32_t num_frames)
         else
         {
             vlc_tick_t now = vlc_tick_now();
-            vlc_tick_t data_ticks = FramesToTicks(sys, num_frames);
-            vlc_tick_t silence_ticks = now + data_ticks - sys->first_play_date;
 
             /* Write silence to reach the first play date */
-            silence_ticks = data_ticks - silence_ticks;
+            vlc_tick_t silence_ticks = sys->first_play_date - now;
             if (silence_ticks > 0)
             {
                 tocopy = TicksToBytes(sys, silence_ticks);
@@ -416,23 +412,25 @@ DataCallback(AAudioStream *as, void *user, void *data_, int32_t num_frames)
         sys->frames_total_bytes -= tocopy;
         sys->timing_report_last_written_bytes += tocopy;
 
-        if (sys->timing_report_last_written_bytes >= sys->timing_report_delay_bytes)
+        int64_t pos_frames;
+        vlc_tick_t system_ts;
+        if (sys->timing_report_last_written_bytes >= sys->timing_report_delay_bytes
+         && GetFrameTimestampLocked(stream, &pos_frames, &system_ts) == VLC_SUCCESS)
         {
             sys->timing_report_last_written_bytes = 0;
 
-            int64_t pos_frames;
-            vlc_tick_t system_ts;
-            if (GetFrameTimestampLocked(stream, &pos_frames, &system_ts) == VLC_SUCCESS)
-            {
-                pos_frames -= sys->frames_flush_pos;
-                assert(pos_frames > 0);
-                vlc_tick_t pos_ticks = FramesToTicks(sys, pos_frames);
-
-                /* Add the start silence to the system time and don't subtract
-                 * it from pos_ticks to avoid (unlikely) negatives ts */
-                system_ts += BytesToTicks(sys, sys->start_silence_bytes);
-                aout_stream_TimingReport(stream, system_ts, pos_ticks);
-            }
+            /* From now on, fetch the timestamp every 1 seconds */
+            sys->timing_report_delay_bytes =
+                TicksToBytes(sys, TIMING_REPORT_DELAY_TICKS);
+
+            pos_frames -= sys->frames_flush_pos;
+            assert(pos_frames > 0);
+            vlc_tick_t pos_ticks = FramesToTicks(sys, pos_frames);
+
+            /* Add the start silence to the system time and don't subtract
+             * it from pos_ticks to avoid (unlikely) negatives ts */
+            system_ts += BytesToTicks(sys, sys->start_silence_bytes);
+            aout_stream_TimingReport(stream, system_ts, pos_ticks);
         }
 
         memcpy(data, f->p_buffer, tocopy);
@@ -584,6 +582,7 @@ Flush(aout_stream_t *stream)
     sys->first_play_date = VLC_TICK_INVALID;
     sys->start_silence_bytes = 0;
     sys->timing_report_last_written_bytes = 0;
+    sys->timing_report_delay_bytes = 0;
     sys->underrun_bytes = 0;
 
     vlc_tick_t unused;
@@ -729,8 +728,6 @@ static int OpenAAudioStream(aout_stream_t *stream, audio_sample_format_t *fmt)
     sys->as = as;
     sys->fmt = *fmt;
 
-    sys->timing_report_delay_bytes = TicksToBytes(sys, TIMING_REPORT_DELAY_TICKS);
-
     return VLC_SUCCESS;
 }
 
@@ -785,6 +782,7 @@ Start(aout_stream_t *stream, audio_sample_format_t *fmt,
     sys->draining = false;
     sys->first_play_date = VLC_TICK_INVALID;
     sys->timing_report_last_written_bytes = 0;
+    sys->timing_report_delay_bytes = 0;
 
     int ret = OpenAAudioStream(stream, fmt);
     if (ret != VLC_SUCCESS)



View it on GitLab: https://code.videolan.org/videolan/vlc/-/compare/ca6417bc9f07231563f023e84bce0c2a682a9acf...84140d6bde72fe989b168fd12f011bd76b22cbc4

-- 
View it on GitLab: https://code.videolan.org/videolan/vlc/-/compare/ca6417bc9f07231563f023e84bce0c2a682a9acf...84140d6bde72fe989b168fd12f011bd76b22cbc4
You're receiving this email because of your account on code.videolan.org.


VideoLAN code repository instance