Changeset 3237 for pjproject/trunk/pjmedia/src/pjmedia/rtcp.c

Timestamp:

Jul 15, 2010 10:18:59 AM (14 years ago)

Author:

nanang

Message:

Re #1103:

• Updated RTCP jitter statistics calculation (in receiving direction) to use "interarrival jitter" (was using "difference D") of RFC 3550.
• Added APIs to reset RTCP statistics.

File:

• pjproject/trunk/pjmedia/src/pjmedia/rtcp.c (modified) (4 diffs)

pjproject/trunk/pjmedia/src/pjmedia/rtcp.c

@@ -137 +137 @@
 
 /*
+ * Initialize bidirectional RTCP statistics.
+ *
+ */
+PJ_DEF(void) pjmedia_rtcp_init_stat(pjmedia_rtcp_stat *stat)
+{
+    pj_time_val now;
+
+    pj_assert(stat);
+
+    pj_bzero(stat, sizeof(pjmedia_rtcp_stat));
+
+    pj_math_stat_init(&stat->rtt);
+    pj_math_stat_init(&stat->rx.loss_period);
+    pj_math_stat_init(&stat->rx.jitter);
+    pj_math_stat_init(&stat->tx.loss_period);
+    pj_math_stat_init(&stat->tx.jitter);
+
+    pj_gettimeofday(&now);
+    stat->start = now;
+}
+
+
+/*
  * Initialize RTCP session.
  */
@@ -195 +218 @@
     pj_gettimeofday(&now);
     sess->tv_base = now;
-    sess->stat.start = now;
     pj_get_timestamp(&sess->ts_base);
     pj_get_timestamp_freq(&sess->ts_freq);
@@ -201 +223 @@
 
     /* Initialize statistics states */
-    pj_math_stat_init(&sess->stat.rtt);
-    pj_math_stat_init(&sess->stat.rx.loss_period);
-    pj_math_stat_init(&sess->stat.rx.jitter);
-    pj_math_stat_init(&sess->stat.tx.loss_period);
-    pj_math_stat_init(&sess->stat.tx.jitter);
+    pjmedia_rtcp_init_stat(&sess->stat);
 
     /* RR will be initialized on receipt of the first RTP packet. */
@@ -351 +369 @@
             sess->jitter += d - ((sess->jitter + 8) >> 4);
 
-            /* Get jitter in usec */
-            if (d < 4294)
-                jitter = d * 1000000 / sess->clock_rate;
+            /* Update jitter stat */
+            jitter = sess->jitter >> 4;
+            
+            /* Convert jitter unit from samples to usec */
+            if (jitter < 4294)
+                jitter = jitter * 1000000 / sess->clock_rate;
             else {
-                jitter = d * 1000 / sess->clock_rate;
+                jitter = jitter * 1000 / sess->clock_rate;
                 jitter *= 1000;
             }
-
-            /* Update jitter stat */
             pj_math_stat_update(&sess->stat.rx.jitter, jitter);
+
 
 #if defined(PJMEDIA_HAS_RTCP_XR) && (PJMEDIA_HAS_RTCP_XR != 0)