Resync audio when drifting.

1 files changed, 20 insertions, 2 deletions

diff --git a/src/soundplayer.cc b/src/soundplayer.cc
index aa05358..b6d14c1 100644
--- a/src/soundplayer.cc
+++ b/src/soundplayer.cc
@@ -29,13 +29,13 @@
 
 #include "audiobackend.h"
 
-#define BUFSZ 512
+#define BUFSZ 128
 
 SoundPlayer::SoundPlayer()
 {
   start();
   pread = 0;
-  for(int i = 0; i < 10; i++) pwrite[i] = BUFSZ * 4;
+  for(int i = 0; i < 10; i++) pwrite[i] = 0;
   memset(ringbuffer, 0, sizeof(ringbuffer));
 }
 
@@ -64,9 +64,27 @@ void SoundPlayer::run()
 
 void SoundPlayer::playSamples(int peer, const char *pcm, size_t size)
 {
+  if(pwrite[peer] == 0) pwrite[peer] = pread + (1.5 * BUFSZ);
+
   short *p = (short*)pcm;
   for(int i = 0; i < size / sizeof(short); i++) {
     ringbuffer[pwrite[peer] % RINGBUFFER] += p[i];
     pwrite[peer]++;
   }
+
+  // If pwrite is behind, repeat the last sample.
+  if((pwrite[peer] - pread) < BUFSZ) {
+    ringbuffer[pwrite[peer] % RINGBUFFER] =
+      ringbuffer[(pwrite[peer] - 1) % RINGBUFFER];
+    pwrite[peer]++;
+    // printf("repeat\n");
+  }
+
+  // If pwrite is too far ahead skip the last sample.
+  if((pwrite[peer] - pread) > (2 * BUFSZ)) {
+    pwrite[peer]--;
+    // printf("skip\n");
+  }
+
+  // printf("pread: %d, pwrite[%d]: %d\n", pread, peer, pwrite[peer]);
 }