Implement ticket #56: Periodically transmit RTP packet on silence, to maintain NAT binding etc.
git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@888 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/pjmedia/src/pjmedia-codec/gsm.c b/pjmedia/src/pjmedia-codec/gsm.c
index f774a5e..8118bcb 100644
--- a/pjmedia/src/pjmedia-codec/gsm.c
+++ b/pjmedia/src/pjmedia-codec/gsm.c
@@ -119,6 +119,7 @@
pjmedia_plc *plc;
pj_bool_t vad_enabled;
pjmedia_silence_det *vad;
+ pj_timestamp last_tx;
};
@@ -365,6 +366,9 @@
pjmedia_plc_save(gsm_data->plc, frame);
}
+ /* Re-init silence_period */
+ pj_set_timestamp32(&gsm_data->last_tx, 0, 0);
+
/* Put in the free list. */
pj_mutex_lock(gsm_codec_factory.mutex);
pj_list_push_front(&gsm_codec_factory.codec_list, codec);
@@ -497,23 +501,31 @@
if (output_buf_len < 33)
return PJMEDIA_CODEC_EFRMTOOSHORT;
- if (input->size < 320)
- return PJMEDIA_CODEC_EPCMTOOSHORT;
+ PJ_ASSERT_RETURN(input->size==320, PJMEDIA_CODEC_EPCMFRMINLEN);
/* Detect silence */
if (gsm_data->vad_enabled) {
pj_bool_t is_silence;
+ pj_int32_t silence_duration;
+
+ silence_duration = pj_timestamp_diff32(&gsm_data->last_tx,
+ &input->timestamp);
is_silence = pjmedia_silence_det_detect(gsm_data->vad,
input->buf,
- input->size / 2,
+ (input->size >> 1),
NULL);
- if (is_silence) {
+ if (is_silence &&
+ PJMEDIA_CODEC_MAX_SILENCE_PERIOD != -1 &&
+ silence_duration < PJMEDIA_CODEC_MAX_SILENCE_PERIOD)
+ {
output->type = PJMEDIA_FRAME_TYPE_NONE;
output->buf = NULL;
output->size = 0;
- output->timestamp.u64 = input->timestamp.u64;
+ output->timestamp = input->timestamp;
return PJ_SUCCESS;
+ } else {
+ gsm_data->last_tx = input->timestamp;
}
}