tell the other side that we're using 20 ms packetization for iLBC

- we need to investigate support for refusing offers of 30 ms (like the Nokia
  e-series) or supporting it.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@36623 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 243d56a938abb9587c2efdfc5a75f0fec28dce89..2a290219f8f19024294da8f7d1836a68533819e6 100644 (file)
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -5575,9 +5575,14 @@ static void add_codec_to_sdp(const struct sip_pvt *p, int codec, int sample_rate
        ast_build_string(a_buf, a_size, "a=rtpmap:%d %s/%d\r\n", rtp_code,
                         ast_rtp_lookup_mime_subtype(1, codec),
                         sample_rate);
-       if (codec == AST_FORMAT_G729A)
+       if (codec == AST_FORMAT_G729A) {
                /* Indicate that we don't support VAD (G.729 annex B) */
                ast_build_string(a_buf, a_size, "a=fmtp:%d annexb=no\r\n", rtp_code);
+       } else if (codec == AST_FORMAT_ILBC) {
+               /* Add information about us using only 20 ms packetization */
+               ast_build_string(a_buf, a_size, "a=fmtp:%d mode=20\r\n", rtp_code);
+       
+       }
 }
 
 /*! \brief Get Max T.38 Transmision rate from T38 capabilities */