Receive rtp (opus) stream from ffmpeg on other computer with VLC

Question

I am currently trying to get an opus stream to play on a separate computer using VLC.

Currently the setup is as follows:

Odroid-U2 running ffmpeg to capture audio and send as rtp opus stream to remote computer.... command used: ffmpeg -f alsa -ac 1 -i hw:0 -acodec libopus -ab 32k -ac 1 -f rtp rtp://192.168.0.115:2032

the remote computer (on same local network) is at 192.168.0.115 the Odroid is at 192.168.0.124

If i use libmp3lame in libopus's place then the stream will run through without a problem and will not prompt the fact that it requires sdp....

VLC output on remote computer:

SDP required: A description in SDP format is required to receive the RTP stream. Note that rtp:// URIs cannot work with dynamic RTP payload format (97).

If i use an *.sdp file that I drop into vlc to play the stream it does nothing (no errors and no playback)

SDP file used:

    SDP:
    v=0
    o=- 0 0 IN IP4 127.0.0.1
    s=No Name
    c=IN IP4 192.168.0.115
    t=0 0
    a=tool:libavformat 55.2.100
    m=audio 2032 RTP/AVP 97
    b=AS:32
    a=rtpmap:97 opus/48000

ffmpeg output on Odroid:

    linaro@linaro-ubuntu-desktop:~$ ffmpeg -f alsa -ac 1 -i hw:0 -acodec libopus -ab 32k -ac 1         -f rtp rtp://192.168.0.115:2032
    ffmpeg version git-2013-04-13-87dd62e Copyright (c) 2000-2013 the FFmpeg developers
      built on Apr 13 2013 09:47:34 with gcc 4.6 (Ubuntu/Linaro 4.6.3-1ubuntu5)
      configuration: --enable-gpl --enable-libmp3lame --enable-libopencore-amrnb --enable-        libopencore-amrwb --enable-libspeex --enable-librtmp --enable-libtheora --enable-libvorbis         --enable-libvpx --enable-x11grab --enable-libx264 --enable-nonfree --enable-version3         --enable-libopus
      libavutil      52. 26.100 / 52. 26.100
      libavcodec     55.  2.100 / 55.  2.100
      libavformat    55.  2.100 / 55.  2.100
      libavdevice    55.  0.100 / 55.  0.100
      libavfilter     3. 53.101 /  3. 53.101
      libswscale      2.  2.100 /  2.  2.100
      libswresample   0. 17.102 /  0. 17.102
      libpostproc    52.  3.100 / 52.  3.100
    Guessed Channel Layout for  Input Stream #0.0 : mono
    Input #0, alsa, from 'hw:0':
      Duration: N/A, start: 1365868129.196234, bitrate: 768 kb/s
        Stream #0:0: Audio: pcm_s16le, 48000 Hz, mono, s16, 768 kb/s
    Output #0, rtp, to 'rtp://192.168.0.115:2032':
      Metadata:
        encoder         : Lavf55.2.100
        Stream #0:0: Audio: opus, 48000 Hz, mono, s16, 32 kb/s
    Stream mapping:
      Stream #0:0 -> #0:0 (pcm_s16le -> libopus)
    SDP:
    v=0
    o=- 0 0 IN IP4 127.0.0.1
    s=No Name
    c=IN IP4 192.168.0.115
    t=0 0
    a=tool:libavformat 55.2.100
    m=audio 2032 RTP/AVP 97
    b=AS:32
    a=rtpmap:97 opus/48000

Any help is greatly appreciated....

Regards

Morgan Morgan · Accepted Answer · 2015-06-27T12:02:55

Just remove the "SDP:" line so that your sdp file only contains:

v=0
o=- 0 0 IN IP4 127.0.0.1
s=No Name
c=IN IP4 192.168.0.115
t=0 0
a=tool:libavformat 55.2.100
m=audio 2032 RTP/AVP 97
b=AS:32
a=rtpmap:97 opus/48000

Receive rtp (opus) stream from ffmpeg on other computer with VLC

1 Answers