gistfile1.txt

iMac-de-jm:mp4 jm$ ffmpeg -i Barbapapa.MP4 - i Ainsi\ font\,\ font\,\ font\,\ les\ petites\ marionnettes.MP4
ffmpeg version 1.2.4 Copyright (c) 2000-2013 the FFmpeg developers
  built on Feb 17 2014 09:08:33 with Apple LLVM version 5.0 (clang-500.2.79) (based on LLVM 3.3svn)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/1.2.4 --enable-shared --enable-pthreads --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables --enable-avresample --enable-vda --cc=clang --host-cflags= --host-ldflags= --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-libxvid
  libavutil      52. 18.100 / 52. 18.100
  libavcodec     54. 92.100 / 54. 92.100
  libavformat    54. 63.104 / 54. 63.104
  libavdevice    54.  3.103 / 54.  3.103
  libavfilter     3. 42.103 /  3. 42.103
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Barbapapa.MP4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    creation_time   : 2014-01-06 23:22:08
  Duration: 00:04:59.21, start: 0.000000, bitrate: 479 kb/s
    Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p, 640x360, 381 kb/s, 25 fps, 25 tbr, 50 tbn, 50 tbc
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 96 kb/s
    Metadata:
      creation_time   : 2014-01-06 23:22:09
      handler_name    : IsoMedia File Produced by Google, 5-11-2011
[NULL @ 0x7ffda991f400] Unable to find a suitable output format for 'pipe:'
pipe:: Invalid argument