Changeset 3945 for pjproject/trunk/pjsip/src/pjsua-lib/pjsua_media.c

Timestamp:

Jan 27, 2012 9:12:59 AM (12 years ago)

Author:

nanang

Message:

Re #1244: Added bandwidth info in SDP ("b=" lines) based on codec bitrate settings. Two SDP bandwidth types/modifiers are used: AS in session level & TIAS in media level.

File:

• pjproject/trunk/pjsip/src/pjsua-lib/pjsua_media.c (modified) (4 diffs)

pjproject/trunk/pjsip/src/pjsua-lib/pjsua_media.c

@@ -1939 +1939 @@
     pjmedia_sdp_neg_state sdp_neg_state = PJMEDIA_SDP_NEG_STATE_NULL;
     unsigned mi;
+    unsigned tot_bandw_tias = 0;
     pj_status_t status;
 
@@ -2012 +2013 @@
         pjmedia_sdp_media *m = NULL;
         pjmedia_transport_info tpinfo;
+        unsigned i;
 
         if (rem_sdp && mi >= rem_sdp->media_count) {
@@ -2109 +2111 @@
             sdp->conn = pjmedia_sdp_conn_clone(pool, m->conn);
         }
+
+        
+        /* Find media bandwidth info */
+        for (i = 0; i < m->bandw_count; ++i) {
+            const pj_str_t STR_BANDW_MODIFIER_TIAS = { "TIAS", 4 };
+            if (!pj_stricmp(&m->bandw[i]->modifier, &STR_BANDW_MODIFIER_TIAS))
+            {
+                tot_bandw_tias += m->bandw[i]->value;
+                break;
+            }
+        }
     }
 
@@ -2133 +2146 @@
         pjmedia_sdp_attr_add(&sdp->attr_count, sdp->attr, a);
 
+    }
+
+
+    /* Add bandwidth info in session level using bandwidth modifier "AS". */
+    if (tot_bandw_tias) {
+        unsigned bandw;
+        const pj_str_t STR_BANDW_MODIFIER_AS = { "AS", 2 };
+        pjmedia_sdp_bandw *b;
+
+        /* AS bandwidth = RTP bitrate + RTCP bitrate.
+         * RTP bitrate  = payload bitrate (total TIAS) + overheads (~16kbps).
+         * RTCP bitrate = est. 5% of RTP bitrate.
+         * Note that AS bandwidth is in kbps.
+         */
+        bandw = tot_bandw_tias + 16000;
+        bandw += bandw * 5 / 100;
+        b = PJ_POOL_ALLOC_T(pool, pjmedia_sdp_bandw);
+        b->modifier = STR_BANDW_MODIFIER_AS;
+        b->value = bandw / 1000;
+        sdp->bandw[sdp->bandw_count++] = b;
     }