jitterbuffer: flesh out buffering mode some more

Add a buffering state to the jitterbuffer and wait until buffering ends before
pushing out packets.

gst/rtpmanager/gstrtpjitterbuffer.c

@@ -1438,6 +1438,9 @@ again:
     id = NULL;
     /* always wait if we are blocked */
     if (G_LIKELY (!priv->blocked)) {
+      /* we're buffering, wait */
+      if (rtp_jitter_buffer_is_buffering (priv->jbuf))
+        goto do_wait;
       /* if we have a packet, we can exit the loop and grab it */
       if (rtp_jitter_buffer_num_packets (priv->jbuf) > 0)
         break;
@@ -1460,6 +1463,7 @@ again:
         GST_OBJECT_UNLOCK (jitterbuffer);
       }
     }
+  do_wait:
     /* now we wait */
     GST_DEBUG_OBJECT (jitterbuffer, "waiting");
     priv->waiting = TRUE;

gst/rtpmanager/rtpjitterbuffer.c

@@ -125,6 +125,12 @@ void
 rtp_jitter_buffer_set_mode (RTPJitterBuffer * jbuf, RTPJitterBufferMode mode)
 {
   jbuf->mode = mode;
+
+  if (mode == RTP_JITTER_BUFFER_MODE_BUFFER) {
+    /* when we're in buffering mode, always set our state to buffering, we'll
+     * get out of it when we push the next buffer */
+    jbuf->buffering = TRUE;
+  }
 }
 
 /**
@@ -510,14 +516,19 @@ rtp_jitter_buffer_insert (RTPJitterBuffer * jbuf, GstBuffer * buf,
         time = 0;
       else
         time = -1;
-
       time = calculate_skew (jbuf, rtptime, time, clock_rate, max_delay);
       break;
     case RTP_JITTER_BUFFER_MODE_SLAVE:
       time = calculate_skew (jbuf, rtptime, time, clock_rate, max_delay);
       break;
     case RTP_JITTER_BUFFER_MODE_BUFFER:
-      time = GST_BUFFER_TIMESTAMP (buf);
+      /* send -1 for all timestamps except the first one. This will make the
+       * timestamps increase according to the RTP timestamps. When in buffering
+       * mode we will adjust the outgoing timestamps relative with how long we
+       * buffered */
+      if (jbuf->base_time != -1)
+        time = -1;
+      time = calculate_skew (jbuf, rtptime, time, clock_rate, max_delay);
       break;
     default:
       break;
@@ -607,6 +618,21 @@ rtp_jitter_buffer_flush (RTPJitterBuffer * jbuf)
     gst_buffer_unref (buffer);
 }
 
+/**
+ * rtp_jitter_buffer_is_buffering:
+ * @jbuf: an #RTPJitterBuffer
+ *
+ * Check if @jbuf is buffering currently. Users of the jitterbuffer should not
+ * pop packets while in buffering mode.
+ *
+ * Returns: the buffering state of @jbuf
+ */
+gboolean
+rtp_jitter_buffer_is_buffering (RTPJitterBuffer * jbuf)
+{
+  return jbuf->buffering;
+}
+
 /**
  * rtp_jitter_buffer_num_packets:
  * @jbuf: an #RTPJitterBuffer
@@ -618,16 +644,9 @@ rtp_jitter_buffer_flush (RTPJitterBuffer * jbuf)
 guint
 rtp_jitter_buffer_num_packets (RTPJitterBuffer * jbuf)
 {
-  guint result;
-
   g_return_val_if_fail (jbuf != NULL, 0);
 
-  if (!jbuf->buffering)
+  return jbuf->packets->length;
-    result = jbuf->packets->length;
-  else
-    result = 0;
-
-  return result;
 }
 
 /**

gst/rtpmanager/rtpjitterbuffer.h

@@ -120,6 +120,8 @@ GstBuffer *           rtp_jitter_buffer_pop              (RTPJitterBuffer *jbuf)
 
 void                  rtp_jitter_buffer_flush            (RTPJitterBuffer *jbuf);
 
+gboolean              rtp_jitter_buffer_is_buffering     (RTPJitterBuffer * jbuf);
+
 guint                 rtp_jitter_buffer_num_packets      (RTPJitterBuffer *jbuf);
 guint32               rtp_jitter_buffer_get_ts_diff      (RTPJitterBuffer *jbuf);