sfile@ubuntu:~/Downloads$ ffmpeg -i concat:"w1.mp4|w2.mp4|w3.mp4|w4.mp4" -codec copy outp.mp4
ffmpeg version N-76944-g15206ff Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.8 (Ubuntu 4.8.4-2ubuntu1~14.04)
  configuration: --extra-libs=-ldl --prefix=/opt/ffmpeg --enable-avresample --disable-debug --enable-nonfree --enable-gpl --enable-version3 --enable-libopencore-amrnb --enable-libopencore-amrwb --disable-decoder=amrnb --disable-decoder=amrwb --enable-libpulse --enable-libdcadec --enable-libfreetype --enable-libx264 --enable-libx265 --enable-libfdk-aac --enable-libvorbis --enable-libmp3lame --enable-libopus --enable-libvpx --enable-libspeex --enable-libass --enable-avisynth --enable-libsoxr --enable-libxvid --enable-libvo-aacenc --enable-libvidstab
  libavutil      55.  9.100 / 55.  9.100
  libavcodec     57. 16.101 / 57. 16.101
  libavformat    57. 19.100 / 57. 19.100
  libavdevice    57.  0.100 / 57.  0.100
  libavfilter     6. 17.100 /  6. 17.100
  libavresample   3.  0.  0 /  3.  0.  0
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xaed4240] Found duplicated MOOV Atom. Skipped it
    Last message repeated 2 times
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'concat:w1.mp4|w2.mp4|w3.mp4|w4.mp4':
  Metadata:
    encoder         : Lavf56.4.101
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
  Duration: 00:10:25.48, start: 0.001882, bitrate: 2628 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x480 [SAR 1:1 DAR 4:3], 696 kb/s, 25 fps, 25 tbr, 12800 tbn, 50 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 127 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
[mp4 @ 0xaeda060] Codec for stream 0 does not use global headers but container format requires global headers
[mp4 @ 0xaeda060] Codec for stream 1 does not use global headers but container format requires global headers
Output #0, mp4, to 'outp.mp4':
  Metadata:
    compatible_brands: isomiso2avc1mp41
    major_brand     : isom
    minor_version   : 512
    encoder         : Lavf57.19.100
    Stream #0:0(und): Video: h264 ([33][0][0][0] / 0x0021), yuv420p, 640x480 [SAR 1:1 DAR 4:3], q=2-31, 696 kb/s, 25 fps, 25 tbr, 12800 tbn, 12800 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) ([64][0][0][0] / 0x0040), 44100 Hz, stereo, 127 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 2117 fps=0.0 q=-1.0 size=    9036kB time=00:01:24.59 bitrate= 875.1kbits/frame= 6755 fps=6707 q=-1.0 size=   28509kB time=00:04:30.11 bitrate= 864.6kbitsframe=12760 fps=8380 q=-1.0 size=   51913kB time=00:08:30.32 bitrate= 833.3kbitsframe=15637 fps=8720 q=-1.0 Lsize=   63443kB time=00:10:25.40 bitrate= 831.0kbits/s
video:53176kB audio:9770kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.789279%
sfile@ubuntu:~/Downloads$