From: Mike Brady <mikebrady@eircom.net>
Date: Mon, 17 Dec 2018 17:11:46 +0000 (+0000)
Subject: Further adjustments to the silence thread -- make the sleep time 30 ms, thus if the... 
X-Git-Tag: 3.3RC0~80
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=70cd4fe81f14fe86f15ab14eceba689dda09603b;p=thirdparty%2Fshairport-sync.git

Further adjustments to the silence thread -- make the sleep time 30 ms, thus if the queue goes below 60 ms of samples, silence will be inserted unless an audio write occurred within the last 30 ms.
---

diff --git a/audio_alsa.c b/audio_alsa.c
index 664bb6ae..72fd2ba4 100644
--- a/audio_alsa.c
+++ b/audio_alsa.c
@@ -1464,12 +1464,12 @@ void *alsa_buffer_monitor_thread_code(void *arg) {
 
   debug(1, "alsa: dither will %sbe added to inter-session silence.", use_dither ? "" : "not ");
 
-  int sleep_time_ms = 80;
+  int sleep_time_ms = 30;
   uint64_t sleep_time_in_fp = sleep_time_ms;
   sleep_time_in_fp = sleep_time_in_fp << 32;
   sleep_time_in_fp = sleep_time_in_fp / 1000;
   debug(1,"alsa: sleep_time: %d ms or 0x%" PRIx64 " in fp form.",sleep_time_ms,sleep_time_in_fp);
-  int frames_of_silence = desired_sample_rate * sleep_time_ms / 1000;
+  int frames_of_silence = (desired_sample_rate * sleep_time_ms * 2) / 1000;
   size_t size_of_silence_buffer = frames_of_silence * frame_size;
   // debug(1,"Silence buffer length: %u bytes.",size_of_silence_buffer);
   void *silence = malloc(size_of_silence_buffer);
@@ -1482,11 +1482,11 @@ void *alsa_buffer_monitor_thread_code(void *arg) {
     while (1) {
     	if (config.keep_dac_busy != 0) {
     		uint64_t present_time = get_absolute_time_in_fp();
-    		if ((most_recent_write_time == 0) || ((present_time - most_recent_write_time) > (sleep_time_in_fp/2))) {
+    		if ((most_recent_write_time == 0) || ((present_time - most_recent_write_time) > (sleep_time_in_fp))) {
 					reply = delay(&buffer_size);
 					if (reply != 0)
 						buffer_size = 0;
-					if (buffer_size < (((int)desired_sample_rate * sleep_time_ms) / (1000))) {
+					if (buffer_size < frames_of_silence) {
 						if ((hardware_mixer == 0) && (config.ignore_volume_control == 0) && (config.airplay_volume != 0.0))
 							use_dither = 1;
 						else
@@ -1498,7 +1498,7 @@ void *alsa_buffer_monitor_thread_code(void *arg) {
 					}
 				}
       }   
-      usleep((sleep_time_ms * 1000) / 2); // has a cancellation point in it
+      usleep(sleep_time_ms * 1000); // has a cancellation point in it
 //      pthread_testcancel();
     }
   }