[Ffmpeg-devel] mp3 to amr_nb transcoding and streaming over RTP using ffmpeg

Kite Flyer kiteflyer77
Thu Jan 18 16:52:15 CET 2007

I'm new to ffmpeg and trying to:

A. transcode an mp3 file to amr_nb  (which works fine because I could output
to a .amr file and play it locally)


B. send it to a remote RTP port. But my ethereal version 0.99.0 is reporting
that the AMR payload is malformed in the captured packets.

Here is my ffmpeg cmd line and the outputs.

[root at kansabati ffmpeg-checkout-2007-01-16]# ffmpeg -i sample_ffmpeg.mp3 -ac
1 -ab 8 -ar 8000 -f rtp -acodec amr_nb rtp://
FFmpeg version SVN-r7541, Copyright (c) 2000-2006 Fabrice Bellard, et al.
  configuration:  --enable-amr_nb
  libavutil version: 49.1.0
  libavcodec version: 51.28.0
  libavformat version: 51.7.0
  built on Jan 16 2007 20:08:50, gcc: 3.4.4 20050721 (Red Hat 3.4.4-2)
Input #0, mp3, from 'sample_ffmpeg.mp3':
  Duration: 00:01:29.4, start: 0.000000, bitrate: 159 kb/s
  Stream #0.0: Audio: mp3, 44100 Hz, stereo, 160 kb/s
Output #0, rtp, to 'rtp://':
  Stream #0.0: Audio: amr_nb, 8000 Hz, mono, 8 kb/s
Stream mapping:
  Stream #0.0 -> #0.0
Press [q] to stop encoding
overread, skip -6 enddists: -4 -4
overread, skip -7 enddists: -6 -6
size=     145kB time=89.5 bitrate=  13.2kbits/s
video:0kB audio:92kB global headers:0kB muxing overhead 57.649601%
[root at kansabati ffmpeg-checkout-2007-01-16]#
[root at kansabati ffmpeg-checkout-2007-01-16]#

Can anyone tell me if/ where I'm going wrong? If not so, please give the
pointer to the right version of ffmpeg source that I can use.

Thanks in advance,

More information about the ffmpeg-devel mailing list