$ ffmpeg -i 1.mp4 out.mp4
ffmpeg version 2.7.1 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.3 (crosstool-NG 1.20.0) 20150311 (prerelease)
  configuration: --prefix=/usr --incdir='${prefix}/include/ffmpeg' --arch=i686 --target-os=linux --cross-prefix=/usr/local/x86_64-pc-linux-gnu/bin/x86_64-pc-linux-gnu- --enable-cross-compile --enable-optimizations --enable-pic --enable-gpl --enable-shared --disable-static --enable-version3 --enable-nonfree --enable-libfaac --enable-encoders --enable-pthreads --disable-bzlib --disable-protocol=rtp --disable-muxer=image2 --disable-muxer=image2pipe --disable-swscale-alpha --disable-ffserver --disable-ffplay --disable-devices --disable-bzlib --disable-altivec --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libmp3lame --disable-vaapi --disable-decoder=amrnb --disable-encoder=zmbv --disable-encoder=dca --disable-encoder=ac3 --disable-encoder=ac3_fixed --disable-encoder=eac3 --disable-decoder=dca --disable-decoder=eac3 --disable-decoder=truehd --cc=/usr/local/x86_64-pc-linux-gnu/bin/x86_64-pc-linux-gnu-ccache-gcc --enable-yasm --enable-libx264 --enable-encoder=libx264
  libavutil      54. 27.100 / 54. 27.100
  libavcodec     56. 41.100 / 56. 41.100
  libavformat    56. 36.100 / 56. 36.100
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 16.101 /  5. 16.101
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  2.100 /  1.  2.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '1.mp4':
  Metadata:
    major_brand     : dash
    minor_version   : 0
    compatible_brands: iso6avc1mp41
    creation_time   : 2016-10-23 17:03:32
  Duration: 21:37:08.05, start: 77825.952018, bitrate: 0 kb/s
    Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuvj420p(pc, bt709), 1920x1080 [SAR 189:190 DAR 168:95], 0 kb/s, 15 fps, 15 tbr, 90k tbn, 30 tbc (default)
    Metadata:
      creation_time   : 2016-10-23 17:03:32
      handler_name    : VideoHandler
      encoder         : EvoStream Media Server
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 11025 Hz, mono, fltp (default)
    Metadata:
      creation_time   : 2016-10-23 17:03:32
      handler_name    : SoundHandler
No pixel format specified, yuvj420p for H.264 encoding chosen.
Use -pix_fmt yuv420p for compatibility with outdated media players.
Output #0, mp4, to 'out.mp4':
  Metadata:
    major_brand     : dash
    minor_version   : 0
    compatible_brands: iso6avc1mp41
    Stream #0:0(und): Video: h264, none, q=2-31, 128 kb/s, SAR 189:190 DAR 0:0, 15 fps (default)
    Metadata:
      creation_time   : 2016-10-23 17:03:32
      handler_name    : VideoHandler
      encoder         : Lavc56.41.100 libx264
    Stream #0:1(und): Audio: aac, 0 channels, 128 kb/s (default)
    Metadata:
      creation_time   : 2016-10-23 17:03:32
      handler_name    : SoundHandler
      encoder         : Lavc56.41.100 libfaac
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (aac (native) -> aac (libfaac))
Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height