$ffmpeg -i complex.mkv
ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 5.5.0 (GCC)
....
Metadata:
    COM.ANDROID.VERSION: 7.0
    MAJOR_BRAND     : mp42
    MINOR_VERSION   : 0
    COMPATIBLE_BRANDS: isommp42
    ENCODER         : Lavf57.83.100
  Duration: 00:00:51.84, start: 0.000000, bitrate: 5748 kb/s
    Stream #0:0: Video: h264 (High), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], 30 fps, 30 tbr, 1k tbn, 60 tbc (default)
    Metadata:
      ENCODER         : Lavc57.64.101 libx264
      DURATION        : 00:00:51.836000000
    Stream #0:1: Audio: vorbis, 48000 Hz, stereo, fltp (default)
    Metadata:
      ENCODER         : Lavc57.64.101 libvorbis
      DURATION        : 00:00:51.783000000
At least one output file must be specified