Fix #1188:

 - Fixed jitter buffer progressive discard by returning 'missing' frame after discarded frame(s) so the PLC will be invoked to align the audio signal.
 - Modified conditions in jitter buffer test data for this fix.



git-svn-id: http://svn.pjsip.org/repos/pjproject/trunk@3396 74dad513-b988-da41-8d7b-12977e46ad98

2 files changed, 27 insertions, 14 deletions

diff --git a/pjmedia/build/Jbtest.dat b/pjmedia/build/Jbtest.dat
index 41eb0ed7..b2f4999d 100644
--- a/pjmedia/build/Jbtest.dat
+++ b/pjmedia/build/Jbtest.dat
@@ -143,7 +143,7 @@ PGGGGPPPGPPGPPPGGPGG PGPGPPGGPPGGPPPGGGPG PGGGGPPPGPPGPPPGGPGG
 %adaptive 0 0 10
 !burst	    4
 !discard    68 <- number of PUT - GET, JB does shrinking by discarding frames
-!lost	    0
+!lost	    68 <- ticket #1188, normal frame after discarded frame is flagged 'lost' to align signal
 !empty	    4
 !delay	    8  <- should be less than or equal to twice of burst
 P PGPGPPGGPPPPGGPGGGPG PGGGGPPPGPPGPPPGGPGG P PGPGPPGGPPPPGGPGGGPG 
@@ -293,7 +293,7 @@ PGPGPGPGPGPGPGPGPGPG PGPGPGPGPGPGPGPGPGPG PGPGPGPGPGPGPGPGPGPG
 %adaptive 0 0 10
 !burst	    1
 !discard    50 <- frames discarded for delay adaptation
-!lost	    0
+!lost	    50 <- ticket #1188, normal frame after discarded frame is flagged 'lost' to align signal
 !empty	    0
 !delay	    25 <- average delay, JB is able to adapt the delay
 PPPPPPPPPPPPPPPPPPPP PPPPPPPPPPPPPPPPPPPP PPPPPPPPPP
@@ -347,7 +347,7 @@ PGGGGPPPGPPGPPPGGPGG PGPGPPGGPPGGPPPGGGPG PGGGGPPPGPPGPPPGGPGG
 %fixed 10
 !burst	    1
 !discard    50 <- frames discarded for delay adaptation
-!lost	    0
+!lost	    50 <- ticket #1188, normal frame after discarded frame is flagged 'lost' to align signal
 !empty	    0
 !delay	    20 <- average delay, twice of minimal prefetch
 PPPPPPPPPPPPPPPPPPPP PPPPPPPPPPPPPPPPPPPP PPPPPPPPPP
@@ -371,7 +371,7 @@ PGPGPGPGPGPGPGPGPGPG PGPGPGPGPGPGPGPGPGPG PGPGPGPGPG
 %adaptive 0 0 40
 !burst	    10
 !discard    300 <- not so relevant for long period session with many delay adjustments needed (i.e: for first burst and periodic spikes)
-!lost	    0
+!lost	    300 <- ticket #1188, normal frame after discarded frame is flagged 'lost' to align signal
 !empty	    60 <- delay adjustment effect, as there is actually no drift
 !delay	    20 <- twice of burst level average
 PPPPPPPPPPPPPPPPPPPP PPPPPPPPPPPPPPPPPPPP PPPPPPPPPP
diff --git a/pjmedia/src/pjmedia/jbuf.c b/pjmedia/src/pjmedia/jbuf.c
index 7a863f2a..fcd6723e 100644
--- a/pjmedia/src/pjmedia/jbuf.c
+++ b/pjmedia/src/pjmedia/jbuf.c
@@ -261,26 +261,39 @@ static pj_bool_t jb_framelist_get(jb_framelist_t *framelist,
 				  pj_uint32_t *bit_info) 
 {
     if (framelist->size) {
+	pj_bool_t prev_discarded = PJ_FALSE;
 
 	/* Skip discarded frames */
 	while (framelist->frame_type[framelist->head] ==
 	       PJMEDIA_JB_DISCARDED_FRAME)
 	{
 	    jb_framelist_remove_head(framelist, 1);
+	    prev_discarded = PJ_TRUE;
 	}
 
 	/* Return the head frame if any */
 	if (framelist->size) {
-	    pj_memcpy(frame, 
-		      framelist->content + 
-		      framelist->head * framelist->frame_size,
-		      framelist->frame_size);
-	    *p_type = (pjmedia_jb_frame_type) 
-		      framelist->frame_type[framelist->head];
-	    if (size)
-		*size   = framelist->content_len[framelist->head];
-	    if (bit_info)
-		*bit_info = framelist->bit_info[framelist->head];
+	    if (prev_discarded) {
+		/* Ticket #1188: when previous frame(s) was discarded, return
+		 * 'missing' frame to trigger PLC to get smoother signal.
+		 */
+		*p_type = PJMEDIA_JB_MISSING_FRAME;
+		if (size)
+		    *size = 0;
+		if (bit_info)
+		    *bit_info = 0;
+	    } else {
+		pj_memcpy(frame, 
+			  framelist->content + 
+			  framelist->head * framelist->frame_size,
+			  framelist->frame_size);
+		*p_type = (pjmedia_jb_frame_type) 
+			  framelist->frame_type[framelist->head];
+		if (size)
+		    *size   = framelist->content_len[framelist->head];
+		if (bit_info)
+		    *bit_info = framelist->bit_info[framelist->head];
+	    }
 
 	    //pj_bzero(framelist->content + 
 	    //	 framelist->head * framelist->frame_size,