ffmpeg version 3.0.8 Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 6.3.0 (Alpine 6.3.0)
  configuration: --enable-gpl --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-libvpx --enable-libvorbis --enable-libopus --enable-libfreetype --enable-gnutls
  libavutil      55. 17.103 / 55. 17.103
  libavcodec     57. 24.102 / 57. 24.102
  libavformat    57. 25.100 / 57. 25.100
  libavdevice    57.  0.101 / 57.  0.101
  libavfilter     6. 31.100 /  6. 31.100
  libswscale      4.  0.100 /  4.  0.100
  libswresample   2.  0.101 /  2.  0.101
  libpostproc    54.  0.100 / 54.  0.100
Splitting the commandline.
Reading option '-v' ... matched as option 'v' (set logging level) with argument '9'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument '99'.
Reading option '-i' ... matched as input url with argument '/home/h264_pix_fmt_444.mkv'.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option v (set logging level) with argument 9.
Successfully parsed a group of options.
Parsing a group of options: input url /home/h264_pix_fmt_444.mkv.
Successfully parsed a group of options.
Opening an input file: /home/h264_pix_fmt_444.mkv.
[file @ 0x558a78afe740] Setting default whitelist 'file,crypto'
Probing matroska,webm score:100 size:2048
[matroska,webm @ 0x558a78afe160] Format matroska,webm probed with size=2048 and score=100
st:0 removing common factor 1000000 from timebase
st:1 removing common factor 1000000 from timebase
st:2 removing common factor 1000000 from timebase
[matroska,webm @ 0x558a78afe160] Before avformat_find_stream_info() pos: 16994 bytes read:32768 seeks:0
[h264 @ 0x558a78b02900] no picture 
[matroska,webm @ 0x558a78afe160] All info found
[matroska,webm @ 0x558a78afe160] 0: start_time: 0.000 duration: -9223372036854.775
[matroska,webm @ 0x558a78afe160] 1: start_time: 0.000 duration: -9223372036854.775
[matroska,webm @ 0x558a78afe160] 2: start_time: 0.000 duration: 0.005
[matroska,webm @ 0x558a78afe160] stream: start_time: 0.000 duration: 5.088 bitrate=3853 kb/s
[matroska,webm @ 0x558a78afe160] After avformat_find_stream_info() pos: 446280 bytes read:456025 seeks:0 frames:5
Input #0, matroska,webm, from '/home/h264_pix_fmt_444.mkv':
  Metadata:
    ENCODER         : Lavf57.56.101
  Duration: 00:00:05.09, start: 0.000000, bitrate: 3853 kb/s
    Stream #0:0(jpn), 4, 1/1000: Video: h264 (High 4:4:4 Predictive), 4 reference frames, yuv444p10le(tv, bt709, left), 1920x1080 (1920x1088), 1001/48000, SAR 1:1 DAR 16:9, 23.98 fps, 23.98 tbr, 1k tbn, 47.95 tbc (default)
    Metadata:
      BPS             : 6436165
      BPS-eng         : 6436165
      DURATION-eng    : 00:23:42.088000000
      NUMBER_OF_FRAMES: 34096
      NUMBER_OF_FRAMES-eng: 34096
      NUMBER_OF_BYTES : 1144099142
      NUMBER_OF_BYTES-eng: 1144099142
      _STATISTICS_WRITING_APP: mkvmerge v10.0.0 ('To Drown In You') 64bit
      _STATISTICS_WRITING_APP-eng: mkvmerge v10.0.0 ('To Drown In You') 64bit
      _STATISTICS_WRITING_DATE_UTC: 2017-03-25 23:48:31
      _STATISTICS_WRITING_DATE_UTC-eng: 2017-03-25 23:48:31
      _STATISTICS_TAGS: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      DURATION        : 00:00:05.088000000
    Stream #0:1(jpn), 1, 1/1000: Audio: flac, 48000 Hz, stereo, s32 (24 bit) (default)
    Metadata:
      BPS             : 1479843
      BPS-eng         : 1479843
      DURATION-eng    : 00:23:42.090000000
      NUMBER_OF_FRAMES: 16666
      NUMBER_OF_FRAMES-eng: 16666
      NUMBER_OF_BYTES : 263058808
      NUMBER_OF_BYTES-eng: 263058808
      _STATISTICS_WRITING_APP: mkvmerge v10.0.0 ('To Drown In You') 64bit
      _STATISTICS_WRITING_APP-eng: mkvmerge v10.0.0 ('To Drown In You') 64bit
      _STATISTICS_WRITING_DATE_UTC: 2017-03-25 23:48:31
      _STATISTICS_WRITING_DATE_UTC-eng: 2017-03-25 23:48:31
      _STATISTICS_TAGS: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      DURATION        : 00:00:05.034000000
    Stream #0:2(spa), 0, 1/1000: Subtitle: ass (default)
    Metadata:
      BPS             : 16370
      BPS-eng         : 16370
      DURATION-eng    : 00:22:42.660000000
      NUMBER_OF_FRAMES: 8163
      NUMBER_OF_FRAMES-eng: 8163
      NUMBER_OF_BYTES : 2788473
      NUMBER_OF_BYTES-eng: 2788473
      _STATISTICS_WRITING_APP: mkvmerge v10.0.0 ('To Drown In You') 64bit
      _STATISTICS_WRITING_APP-eng: mkvmerge v10.0.0 ('To Drown In You') 64bit
      _STATISTICS_WRITING_DATE_UTC: 2017-03-25 23:48:31
      _STATISTICS_WRITING_DATE_UTC-eng: 2017-03-25 23:48:31
      _STATISTICS_TAGS: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
      DURATION        : 00:00:00.000000000
Successfully opened the file.
At least one output file must be specified
[AVIOContext @ 0x558a78b06860] Statistics: 456025 bytes read, 0 seeks