root@test:/tmp# ffmpeg  -i concat:1.mp4\|2.mp4 -c copy  output.mp4
ffmpeg version 2.4.2 Copyright (c) 2000-2014 the FFmpeg developers
  built on Oct 18 2014 15:38:04 with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
  configuration: --prefix=/root/ffmpeg/target --extra-cflags='-I/root/ffmpeg/target/include -static' --extra-ldflags='-L/root/ffmpeg/target/lib -lm -static' - --disable-debug --disable-shared --enable-static --extra-cflags=--static --disable-ffplay --disable-ffserver --disable-doc --enable-openssl --enable-gpl --enable-pthreads --enable-postproc --enable-libass --enable-gray --enable-runtime-cpudetect --enable-libfaac --enable-gnutls --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libx264 --enable-libxvid --enable-bzlib --enable-zlib --enable-nonfree --enable-version3 --enable-libvpx --enable-libxavs --disable-devices --enable-librtmp --extra-libs='-lrtmp -lnettle -lhogweed -lgmp -lssl -lcrypto -lz -lc -ldl'
  libavutil      54.  7.100 / 54.  7.100
  libavcodec     56.  1.100 / 56.  1.100
  libavformat    56.  4.101 / 56.  4.101
  libavdevice    56.  0.100 / 56.  0.100
  libavfilter     5.  1.100 /  5.  1.100
  libswscale      3.  0.100 /  3.  0.100
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  0.100 / 53.  0.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x27ea760] Found duplicated MOOV Atom. Skipped it
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'concat:1.mp4|2.mp4':
  Metadata:
    encoder         : HandBrake 0.9.4 2009112300
    major_brand     : mp42
    minor_version   : 0
    creation_time   : 2010-03-20 21:29:11
    compatible_brands: mp42isomavc1
  Duration: 00:00:05.57, start: 0.000000, bitrate: 1102 kb/s
    Stream #0:0(und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p(tv, bt709), 560x320, 465 kb/s, 30 fps, 30 tbr, 90k tbn, 60 tbc (default)
    Metadata:
      creation_time   : 2010-03-20 21:29:11
      encoder         : JVT/AVC Coding
    Stream #0:1(eng): Audio: aac (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 83 kb/s (default)
    Metadata:
      creation_time   : 2010-03-20 21:29:11
File 'output.mp4' already exists. Overwrite ? [y/N] y
Output #0, mp4, to 'output.mp4':
  Metadata:
    compatible_brands: mp42isomavc1
    major_brand     : mp42
    minor_version   : 0
    encoder         : Lavf56.4.101
    Stream #0:0(und): Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 560x320, q=2-31, 465 kb/s, 30 fps, 90k tbn, 90k tbc (default)
    Metadata:
      creation_time   : 2010-03-20 21:29:11
      encoder         : JVT/AVC Coding
    Stream #0:1(eng): Audio: aac ([64][0][0][0] / 0x0040), 48000 Hz, mono, 83 kb/s (default)
    Metadata:
      creation_time   : 2010-03-20 21:29:11
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=  166 fps=0.0 q=-1.0 Lsize=     377kB time=00:00:05.56 bitrate= 554.5kbits/s
video:315kB audio:56kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.595011%