RTP Endpoint codec capabilities?

[ma...@hassman.org]

Hi,

Does anyone know of the audio codecs Kurento's RTP Endpoint is capable of delivering?

I have video working via: a=rtpmap:101 H264/90000, but am unable to find a compatible codec for delivering audio. Kurento lists these in sdp_pattern.txt:
  a=rtpmap:98 OPUS/48000/2
  a=rtpmap:99 AMR/8000/1
  a=rtpmap:0 PCMU/8000

However, the receiver (Wowza)  is capable of: AAC, AAC-LC, HE-AAC (accPlus) v1 & v2, MP3, Speex.

Without success, I've experimented with forcing aac (a=rtpmap:0 MP4A-LATM/9000), mp3 (a=rtpmap:0 mpa/44100/2), and speex (a=rtpmap:0 speex/16000). Kurento source code is less than revealing. Gstreamer is worse.
There's a list of gstreamer codecs here: http://gstreamer.freedesktop.org/data/doc/gstreamer/head/pwg/html/section-types-definitions.html#table-audio-types.. but, it's not clear if these are exposed/permitted through Kurento's RTP endpoint.

Anyone have a codec/capability list for Kurento's RTP endpoint?
Thanks in advance!


-Mark

[Remus Alexandru]

Hello,

I don't know about all the audio codecs supported, but I got opus to work:

v=0

o=- 2 2 IN IP4 10.0.0.101

s=

t=0 0

c=IN IP4 10.0.0.101

m=audio 49170 RTP/AVP 111

a=rtpmap:111 opus/48000/2

a=fmtp:111 minptime=10; useinbandfec=1

a=recvonly

m=video 24230 RTP/AVP 100

a=rtpmap:100 H264/90000

a=recvonly

Just be aware that VLC does not have support for opus playback over RTP; ffmpeg on the other hand does and it works as expected:

Input #0, sdp, from 'test3.sdp':   0KB vq=    0KB sq=    0B f=0/0

  Metadata:

    title           :

  Duration: N/A, start: 0.000000, bitrate: N/A

    Stream #0:0: Audio: opus, 48000 Hz, stereo, fltp

    Stream #0:1: Video: h264 (Constrained Baseline), yuv420p(progressive), 640x480 [SAR 1:1 DAR 4:3], 12 fps, 62.50 tbr, 90k tbn, 24 tbc

 433.12 A-V: -0.009 fd= 105 aq=   26KB vq=   89KB sq=    0B f=0/0

Also, I know where was a bug with the sdp processing that gave errors on writing "OPUS" in capital letters => It's important to have it written in lowercase.

Hope this helps and would really like to know if there is any limitations to what codecs KMS supports or are they dependent only on the peers/clients?

Thanks.