add support for EBU-ACIP parameters

add support for EBU-ACIP parameters in the SDP. This can be
enabled with the following config item:

    sdp_ebuacip    yes

Reference: https://tech.ebu.ch/docs/tech/tech3368.pdf

Thanks to Ola Palm from Swedish Radio for the patch

3 files changed, 49 insertions, 0 deletions

diff --git a/include/baresip.h b/include/baresip.h
index e394e75..efa047c 100644
--- a/include/baresip.h
+++ b/include/baresip.h
@@ -248,6 +248,11 @@ struct config_bfcp {
 };
 #endif
 
+/** SDP */
+struct config_sdp {
+	bool ebuacip;           /**< Enable EBU-ACIP parameters     */
+};
+
 
 /** Core configuration */
 struct config {
@@ -268,6 +273,8 @@ struct config {
 #ifdef USE_VIDEO
 	struct config_bfcp bfcp;
 #endif
+
+	struct config_sdp sdp;
 };
 
 int config_parse_conf(struct config *cfg, const struct conf *conf);
diff --git a/src/audio.c b/src/audio.c
index 116ffaa..422926b 100644
--- a/src/audio.c
+++ b/src/audio.c
@@ -746,6 +746,33 @@ static int add_telev_codec(struct audio *a)
 }
 
 
+/*
+ * EBU ACIP (Audio Contribution over IP) Profile
+ */
+static int set_ebuacip_params(struct audio *au, uint32_t ptime)
+{
+	struct sdp_media *sdp = stream_sdpmedia(au->strm);
+	int jb_id;
+	int jbvalue;
+	int err = 0;
+
+	jb_id = 0;
+	jbvalue = (au->strm->cfg.jbuf_del.max) * ptime;
+
+	/* set ebuacip version */
+	err |= sdp_media_set_lattr(sdp, false, "ebuacip", "version %i", 0);
+
+	/* set jb option, only one in our case */
+	err |= sdp_media_set_lattr(sdp, false, "ebuacip", "jb %i", jb_id);
+
+	/* define jb value in option */
+	err |= sdp_media_set_lattr(sdp, false, "ebuacip",
+				   "jbdef %i fixed %d", jb_id, jbvalue);
+
+	return err;
+}
+
+
 int audio_alloc(struct audio **ap, const struct stream_param *stream_prm,
 		const struct config *cfg,
 		struct call *call, struct sdp_session *sdp_sess, int label,
@@ -803,6 +830,13 @@ int audio_alloc(struct audio **ap, const struct stream_param *stream_prm,
 			goto out;
 	}
 
+	if (cfg->sdp.ebuacip) {
+
+		err = set_ebuacip_params(a, ptime);
+		if (err)
+			goto out;
+	}
+
 	/* Audio codecs */
 	for (le = list_head(aucodecl); le; le = le->next) {
 		err = add_audio_codec(a, stream_sdpmedia(a->strm), le->data);
diff --git a/src/config.c b/src/config.c
index 6662b3c..be26798 100644
--- a/src/config.c
+++ b/src/config.c
@@ -95,6 +95,11 @@ static struct config core_config = {
 		""
 	},
 #endif
+
+	/* SDP */
+	{
+		false
+	},
 };
 
 
@@ -254,6 +259,9 @@ int config_parse_conf(struct config *cfg, const struct conf *conf)
 			   sizeof(cfg->bfcp.proto));
 #endif
 
+	/* SDP */
+	(void)conf_get_bool(conf, "sdp_ebuacip", &cfg->sdp.ebuacip);
+
 	return err;
 }