Changeset 1715 for pjproject/trunk/pjmedia/src/pjmedia/delaybuf.c

Timestamp:

Jan 19, 2008 9:39:52 AM (16 years ago)

Author:

bennylp

Message:

More work on ticket #438: Workaround for frame bursts from audio devices. See the ticket for more information

File:

• pjproject/trunk/pjmedia/src/pjmedia/delaybuf.c (modified) (2 diffs)

pjproject/trunk/pjmedia/src/pjmedia/delaybuf.c

@@ -41 +41 @@
 /* Since there are two operations performed (get & put), */
 /* these macros value must be minimum 2 and should be even number */
-#define WAITING_COUNT   8
-#define LEARN_COUNT     8
+#define WAITING_COUNT   4
+#define LEARN_COUNT     16
+
+/* Number of buffers to add to learnt level for additional stability */
+#define SAFE_MARGIN     2
+
+/*
+ * Some experimental data (with SAFE_MARGIN=1):
+ *
+ * System 1:
+ *  - XP, WMME, 10ms ptime, 
+ *  - Sennheiser Headset+USB sound card
+ *  - Stable delaybuf level: 6, on WAITING_COUNT=4 and LEARNING_COUNT=48
+ *
+ * System 2:
+ *  - XP, WMME, 10ms ptime
+ *  - Onboard SoundMAX Digital Audio
+ *  - Stable delaybuf level: 6, on WAITING_COUNT=4 and LEARNING_COUNT=48
+ */
 
 struct pjmedia_delay_buf
@@ -134 +151 @@
             b->state_count++;
             if (b->state_count == LEARN_COUNT) {
-                /* give ONE frame compensation */
-                b->max_level += 1;
+                /* give SAFE_MARGIN compensation for added stability */
+                b->max_level += SAFE_MARGIN;
                 
                 PJ_LOG(5,(b->obj_name,"Delay buffer start running, level=%u",