From 293f2fda9a300d878a671dc4b2e2c029d0ec3509 Mon Sep 17 00:00:00 2001
From: Giacomo Vacca <giacomo.vacca@gmail.com>
Date: Wed, 28 Sep 2016 11:22:40 -0400
Subject: [PATCH] FS-9584 Separate initial bitrate negotiation from sample
 rates

---
 conf/vanilla/autoload_configs/opus.conf.xml |  4 ++++
 src/mod/codecs/mod_opus/mod_opus.c          | 15 ++++++++++-----
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/conf/vanilla/autoload_configs/opus.conf.xml b/conf/vanilla/autoload_configs/opus.conf.xml
index 98a6b7fd1d..2e05ff6f84 100644
--- a/conf/vanilla/autoload_configs/opus.conf.xml
+++ b/conf/vanilla/autoload_configs/opus.conf.xml
@@ -7,6 +7,10 @@
         <!--<param name="packet-loss-percent" value="10"/>-->
 	<!-- Support asymmetric sample rates -->
         <!--<param name="asymmetric-sample-rates" value="1"/>-->
+
+	<!-- Enable bitrate negotiation -->
+        <!--<param name="bitrate-negotiation" value="1"/>-->
+
 	<!-- Keep FEC Enabled -->
         <param name="keep-fec-enabled" value="1"/>
 	<!--<param name="use-jb-lookahead" value="true"/> -->
diff --git a/src/mod/codecs/mod_opus/mod_opus.c b/src/mod/codecs/mod_opus/mod_opus.c
index 4a46c3f1e3..d4b5b81ac3 100644
--- a/src/mod/codecs/mod_opus/mod_opus.c
+++ b/src/mod/codecs/mod_opus/mod_opus.c
@@ -129,6 +129,7 @@ struct {
 	int sprop_maxcapturerate;
 	int plpct;
 	int asymmetric_samplerates;
+	int bitrate_negotiation;
 	int keep_fec;
 	int fec_decode;
 	int adjust_bitrate;
@@ -490,30 +491,32 @@ static switch_status_t switch_opus_init(switch_codec_t *codec, switch_codec_flag
 	memset(&codec_fmtp, '\0', sizeof(struct switch_codec_fmtp));
 	codec_fmtp.private_info = &opus_codec_settings;
 	switch_opus_fmtp_parse(codec->fmtp_in, &codec_fmtp);
-	if (opus_prefs.asymmetric_samplerates) {
+	if (opus_prefs.asymmetric_samplerates || opus_prefs.bitrate_negotiation) {
 		/* save the remote fmtp values, before processing */
 		codec_fmtp_only_remote.private_info = &opus_codec_settings_remote;
 		switch_opus_fmtp_parse(codec->fmtp_in, &codec_fmtp_only_remote);
 	}
 	context->codec_settings = opus_codec_settings;
 
-	/* Verify if the local or remote configuration are lowering maxaveragebitrate and/or maxplaybackrate */
+	/* If bitrate negotiation is allowed, verify whether remote is asking for a smaller maxaveragebitrate */
 	if (opus_prefs.maxaveragebitrate &&
-		 (opus_prefs.maxaveragebitrate < opus_codec_settings_remote.maxaveragebitrate || !opus_codec_settings_remote.maxaveragebitrate)) {
+		 (!opus_prefs.bitrate_negotiation || (opus_prefs.maxaveragebitrate < opus_codec_settings_remote.maxaveragebitrate) || !opus_codec_settings_remote.maxaveragebitrate)) {
 		opus_codec_settings.maxaveragebitrate = opus_prefs.maxaveragebitrate;
 	} else {
 		opus_codec_settings.maxaveragebitrate = opus_codec_settings_remote.maxaveragebitrate;
 	}
 
+	/* If asymmetric sample rates are allowed, verify whether remote is asking for a smaller maxplaybackrate */
 	if (opus_prefs.maxplaybackrate &&
-		 (opus_prefs.maxplaybackrate < opus_codec_settings_remote.maxplaybackrate || !opus_codec_settings_remote.maxplaybackrate)) {
+		 (!opus_prefs.asymmetric_samplerates || (opus_prefs.maxplaybackrate < opus_codec_settings_remote.maxplaybackrate) || !opus_codec_settings_remote.maxplaybackrate)) {
 		opus_codec_settings.maxplaybackrate = opus_prefs.maxplaybackrate;
 	} else {
 		opus_codec_settings.maxplaybackrate=opus_codec_settings_remote.maxplaybackrate;
 	}
 
+	/* If asymmetric sample rates are allowed, verify whether remote is asking for a smaller sprop_maxcapturerate */
 	if (opus_prefs.sprop_maxcapturerate &&
-		 (opus_prefs.sprop_maxcapturerate < opus_codec_settings_remote.sprop_maxcapturerate || !opus_codec_settings_remote.sprop_maxcapturerate)) {
+		 (!opus_prefs.asymmetric_samplerates || (opus_prefs.sprop_maxcapturerate < opus_codec_settings_remote.sprop_maxcapturerate) || !opus_codec_settings_remote.sprop_maxcapturerate)) {
 		opus_codec_settings.sprop_maxcapturerate = opus_prefs.sprop_maxcapturerate;
 	} else {
 		opus_codec_settings.sprop_maxcapturerate = opus_codec_settings_remote.sprop_maxcapturerate;
@@ -987,6 +990,8 @@ static switch_status_t opus_load_config(switch_bool_t reload)
 				opus_prefs.plpct = atoi(val);
 			} else if (!strcasecmp(key, "asymmetric-sample-rates")) {
 				opus_prefs.asymmetric_samplerates = atoi(val);
+			} else if (!strcasecmp(key, "bitrate-negotiation")) {
+				opus_prefs.bitrate_negotiation = atoi(val);
 			} else if (!strcasecmp(key, "use-jb-lookahead")) {
 				opus_prefs.use_jb_lookahead = switch_true(val);
 			} else if (!strcasecmp(key, "keep-fec-enabled")) { /* encoder */