FFmpeg gera arquivo vazio

Question

Estou tentando cortar vídeo 4K @ 60fps usando FFMpeg 3.2.4 (x64) para Windows sem recodificar:

ffmpeg -i D:/video/qc_01.mp4 -c copy -ss 00:27:00 -to 00:56:00 D:/video/01.mp4

Eu recebo um arquivo quase vazio (290 bytes) e isso gera:

D:\video>ffmpeg -i D:/video/qc_01.mp4 -c copy -ss 00:27:00 -to 00:56:00 D:/video/01.mp4 > output.txt
ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 6.3.0 (GCC)
  configuration: --enable-gpl --enable-version3 --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r
--enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-l
ibmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy -
-enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable
-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-zlib
  libavutil      55. 34.101 / 55. 34.101
  libavcodec     57. 64.101 / 57. 64.101
  libavformat    57. 56.101 / 57. 56.101
  libavdevice    57.  1.100 / 57.  1.100
  libavfilter     6. 65.100 /  6. 65.100
  libswscale      4.  2.100 /  4.  2.100
  libswresample   2.  3.100 /  2.  3.100
  libpostproc    54.  1.100 / 54.  1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:/video/qc_01.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp41isom
    creation_time   : 2017-04-15T00:48:17.000000Z
    date            : 2017
  Duration: 00:12:19.26, start: 0.000000, bitrate: 48108 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, smpte170m/smpte170m/bt470m), 3840x2160 [SAR 1:1 DAR 16:9], 47902 kb/s, 59.38 fps, 60 tbr, 60k tbn, 120 tbc
 (default)
    Metadata:
      creation_time   : 2017-04-15T00:48:17.000000Z
      handler_name    : VideoHandler
      encoder         : AVC Coding
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 196 kb/s (default)
    Metadata:
      creation_time   : 2017-04-15T00:48:17.000000Z
      handler_name    : SoundHandler
Output #0, mp4, to 'D:/video/01.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp41isom
    date            : 2017
    encoder         : Lavf57.56.101
    Stream #0:0(und): Video: h264 (High) ([33][0][0][0] / 0x0021), yuv420p(tv, smpte170m/smpte170m/bt470m), 3840x2160 [SAR 1:1 DAR 16:9], q=2-31, 47902 kb/s, 59.38 fps, 60 tbr, 60k
 tbn, 60k tbc (default)
    Metadata:
      creation_time   : 2017-04-15T00:48:17.000000Z
      handler_name    : VideoHandler
      encoder         : AVC Coding
    Stream #0:1(und): Audio: aac (LC) ([64][0][0][0] / 0x0040), 48000 Hz, stereo, 196 kb/s (default)
    Metadata:
      creation_time   : 2017-04-15T00:48:17.000000Z
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=    0 fps=0.0 q=-1.0 Lsize=       0kB time=00:00:00.00 bitrate=N/A speed=   0x
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

D:\video>

    

Answer 1

O vídeo tem 12 minutos de duração. A posição é passada incorretamente. Passando do segundo 27 para o segundo 56:

ffmpeg -i D:/video/qc_01.mp4 -ss 00:00:27 -to 00:00:56 -c copy D:/video/01.mp4