Changeset 868 for pjproject/trunk

Timestamp:

Dec 26, 2006 9:56:38 PM (18 years ago)

Author:

bennylp

Message:

Implement ticket #53: Disable silence detector during the first few seconds of RTP transmission to assist NAT traversal

Location:

pjproject/trunk/pjmedia

Files:

• include/pjmedia/config.h (modified) (1 diff)
• src/pjmedia/stream.c (modified) (8 diffs)

pjproject/trunk/pjmedia/include/pjmedia/config.h

@@ -173 +173 @@
 
 /**
+ * Specify how long (in miliseconds) the stream should suspend the
+ * silence detector/voice activity detector (VAD) during the initial
+ * period of the session.
+ *
+ * Specify zero to disable this feature.
+ *
+ * Default: 600 msec
+ */
+#ifndef PJMEDIA_STREAM_VAD_SUSPEND_MSEC
+#   define PJMEDIA_STREAM_VAD_SUSPEND_MSEC      600
+#endif
+
+
+/**
  * Suggested or default threshold to be set for fixed silence detection
  * or as starting threshold for adaptive silence detection. The threshold

pjproject/trunk/pjmedia/src/pjmedia/stream.c

@@ -89 +89 @@
     pjmedia_codec           *codec;         /**< Codec instance being used. */
     pjmedia_codec_param      codec_param;   /**< Codec param.               */
+    unsigned                 vad_enabled;   /**< VAD enabled in param.      */
     unsigned                 frame_size;    /**< Size of encoded base frame.*/
     pj_bool_t                is_streaming;  /**< Currently streaming?. This
                                                  is used to put RTP marker
                                                  bit.                       */
+    pj_uint32_t              ts_vad_disabled;/**< TS when VAD was disabled. */
+    pj_uint32_t              tx_duration;   /**< TX duration in timestamp.  */
 
     pj_mutex_t              *jb_mutex;
@@ -126 +129 @@
                                    '8', '9', '*', '#',
                                    'A', 'B', 'C', 'D'};
+
+/* Zero PCM frame */
+#define ZERO_PCM_MAX_SIZE   1920    /* 40ms worth of PCM @ 48KHz */
+static pj_int16_t zero_frame[ZERO_PCM_MAX_SIZE];
+
 
 /*
@@ -448 +456 @@
     pj_status_t status = 0;
     struct pjmedia_frame frame_out;
-    unsigned ts_len;
+    unsigned ts_len, samples_per_frame;
+    pjmedia_frame tmp_in_frame;
     void *rtphdr;
     int rtphdrlen;
@@ -462 +471 @@
     ts_len = port->info.samples_per_frame;
 
+    /* Increment transmit duration */
+    stream->tx_duration += ts_len;
+
     /* Init frame_out buffer. */
     frame_out.buf = ((char*)channel->out_pkt) + sizeof(pjmedia_rtp_hdr);
     frame_out.size = 0;
+
+    /* Calculate number of samples per frame */
+    samples_per_frame = stream->codec_param.info.frm_ptime *
+                        stream->codec_param.info.clock_rate *
+                        stream->codec_param.info.channel_cnt /
+                        1000;
+
+    /* If VAD is temporarily disabled during creation, feed zero PCM frame
+     * to the codec.
+     */
+    if (stream->vad_enabled != stream->codec_param.setting.vad &&
+        stream->vad_enabled != 0 &&
+        frame->type == PJMEDIA_FRAME_TYPE_NONE &&
+        samples_per_frame <= ZERO_PCM_MAX_SIZE)
+    {
+        pj_memcpy(&tmp_in_frame, frame, sizeof(pjmedia_frame));
+        frame = &tmp_in_frame;
+
+        tmp_in_frame.buf = zero_frame;
+        tmp_in_frame.size = samples_per_frame * 2;
+        tmp_in_frame.type = PJMEDIA_FRAME_TYPE_AUDIO;
+    }
 
 
@@ -482 +516 @@
 
     } else if (frame->type != PJMEDIA_FRAME_TYPE_NONE) {
-        unsigned ts, samples_per_frame;
+        unsigned ts;
 
         /* Repeatedly call encode if there are multiple frames to be
          * sent.
          */
-        samples_per_frame = stream->codec_param.info.frm_ptime *
-                            stream->codec_param.info.clock_rate *
-                            stream->codec_param.info.channel_cnt /
-                            1000;
 
         for (ts=0; ts<ts_len; ts += samples_per_frame) {
@@ -570 +600 @@
             stream->is_streaming = PJ_FALSE;
         }
+
         return PJ_SUCCESS;
     }
@@ -597 +628 @@
     /* Update stat */
     pjmedia_rtcp_tx_rtp(&stream->rtcp, frame_out.size);
+
+    /* If VAD is temporarily disabled during creation, enable it
+     * after transmitting for VAD_SUSPEND_SEC seconds.
+     */
+    if (stream->vad_enabled != stream->codec_param.setting.vad &&
+        (stream->tx_duration - stream->ts_vad_disabled) > 
+        stream->port.info.clock_rate * PJMEDIA_STREAM_VAD_SUSPEND_MSEC / 1000)
+    {
+        stream->codec_param.setting.vad = stream->vad_enabled;
+        stream->codec->op->modify(stream->codec, &stream->codec_param);
+        PJ_LOG(4,(stream->port.info.name.ptr,"VAD re-enabled"));
+    }
+
 
     return PJ_SUCCESS;
@@ -1028 +1072 @@
         goto err_cleanup;
 
+
+    /* Initially disable the VAD in the stream, to help traverse NAT better */
+    stream->vad_enabled = stream->codec_param.setting.vad;
+    if (stream->vad_enabled) {
+        stream->codec_param.setting.vad = 0;
+        stream->ts_vad_disabled = 0;
+        stream->codec->op->modify(stream->codec, &stream->codec_param);
+        PJ_LOG(4,(stream->port.info.name.ptr,"VAD temporarily disabled"));
+    }
 
     /* Get the frame size: */