No se puede recortar la transmisión de video canalizada con FFmpeg

No se puede recortar la transmisión de video canalizada con FFmpeg

Al intentar recortar un archivo de vídeo que se transmite desde la entrada estándar, solo funciona cuando la duración de inicio es superior a 2,0 segundos para algunos vídeos (falla en los capturados desde un teléfono Android, para ser específicos).

Cuando ssse establece en 2.0, es decir ffmpeg -y -ss 00:00:02.0 -vcodec h264 -acodec aac -i pipe:0 -t 7 output_file.mp4, falla con la salida [mov,mp4,m4a,3gp,3g2,mj2 @ 0xecf920] stream 1, offset 0x65ea3: partial file pipe:0: Invalid data found when processing input.

Aquí está el registro completo:

$ cat camera_landscape.mp4 | ffmpeg -y -ss 00:00:02.0 -vcodec h264 -acodec aac -i pipe:0 -t 7 camera_landscape_test.mp4 
ffmpeg version 2.6.4 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (Debian 4.9.2-10)
  configuration: --prefix=/usr --extra-cflags='-g -O2 -fstack-protector-strong -Wformat -Werror=format-security ' --extra-ldflags='-Wl,-z,relro' --cc='ccache cc' --enable-shared --enable-libmp3lame --enable-gpl --enable-nonfree --enable-libvorbis --enable-pthreads --enable-libfaac --enable-libxvid --enable-postproc --enable-x11grab --enable-libgsm --enable-libtheora --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libspeex --enable-nonfree --disable-stripping --enable-libvpx --enable-libschroedinger --disable-encoder=libschroedinger --enable-version3 --enable-libopenjpeg --enable-librtmp --enable-avfilter --enable-libfreetype --enable-libvo-aacenc --disable-decoder=amrnb --enable-libvo-amrwbenc --enable-libaacplus --libdir=/usr/lib/x86_64-linux-gnu --disable-vda --enable-libbluray --enable-libcdio --enable-gnutls --enable-frei0r --enable-openssl --enable-libass --enable-libopus --enable-fontconfig --enable-libpulse --disable-mips32r2 --disable-mipsdspr1 --disable-mipsdspr2 --enable-libvidstab --enable-libzvbi --enable-avresample --disable-htmlpages --disable-podpages --enable-libutvideo --enable-libfdk-aac --enable-libx265 --enable-libiec61883 --enable-vaapi --enable-libdc1394 --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'pipe:0':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    creation_time   : 2015-09-27 09:46:32
  Duration: 00:00:16.96, start: 0.000000, bitrate: N/A
    Stream #0:0(eng): Video: h264 (Baseline) (avc1 / 0x31637661), yuv420p, 640x480, 5744 kb/s, SAR 1:1 DAR 4:3, 28.68 fps, 28.67 tbr, 90k tbn, 180k tbc (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : VideoHandle
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 95 kb/s (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : SoundHandle
[libx264 @ 0xee1000] using SAR=1/1
[libx264 @ 0xee1000] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
[libx264 @ 0xee1000] profile High, level 3.0
[libx264 @ 0xee1000] 264 - core 146 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'camera_landscape_test.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    encoder         : Lavf56.25.101
    Stream #0:0(eng): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 640x480 [SAR 1:1 DAR 4:3], q=-1--1, 28.67 fps, 11008 tbn, 28.67 tbc (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : VideoHandle
      encoder         : Lavc56.26.100 libx264
    Stream #0:1(eng): Audio: aac (libfaac) ([64][0][0][0] / 0x0040), 48000 Hz, mono, s16, 128 kb/s (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : SoundHandle
      encoder         : Lavc56.26.100 libfaac
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (aac (native) -> aac (libfaac))
[mov,mp4,m4a,3gp,3g2,mj2 @ 0xecf920] stream 1, offset 0x65ea3: partial file
pipe:0: Invalid data found when processing input
frame=    0 fps=0.0 q=0.0 Lsize=       0kB time=00:00:00.00 bitrate=N/A    
video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

Cualquier valor mayor que 2.0 tiene éxito, como tal:

$ cat camera_landscape.mp4 | ffmpeg -y -ss 00:00:02.1 -vcodec h264 -acodec aac -i pipe:0 -t 7 camera_landscape_test.mp4 
ffmpeg version 2.6.4 Copyright (c) 2000-2015 the FFmpeg developers
  built with gcc 4.9.2 (Debian 4.9.2-10)
  configuration: --prefix=/usr --extra-cflags='-g -O2 -fstack-protector-strong -Wformat -Werror=format-security ' --extra-ldflags='-Wl,-z,relro' --cc='ccache cc' --enable-shared --enable-libmp3lame --enable-gpl --enable-nonfree --enable-libvorbis --enable-pthreads --enable-libfaac --enable-libxvid --enable-postproc --enable-x11grab --enable-libgsm --enable-libtheora --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libx264 --enable-libspeex --enable-nonfree --disable-stripping --enable-libvpx --enable-libschroedinger --disable-encoder=libschroedinger --enable-version3 --enable-libopenjpeg --enable-librtmp --enable-avfilter --enable-libfreetype --enable-libvo-aacenc --disable-decoder=amrnb --enable-libvo-amrwbenc --enable-libaacplus --libdir=/usr/lib/x86_64-linux-gnu --disable-vda --enable-libbluray --enable-libcdio --enable-gnutls --enable-frei0r --enable-openssl --enable-libass --enable-libopus --enable-fontconfig --enable-libpulse --disable-mips32r2 --disable-mipsdspr1 --disable-mipsdspr2 --enable-libvidstab --enable-libzvbi --enable-avresample --disable-htmlpages --disable-podpages --enable-libutvideo --enable-libfdk-aac --enable-libx265 --enable-libiec61883 --enable-vaapi --enable-libdc1394 --disable-altivec --shlibdir=/usr/lib/x86_64-linux-gnu
  libavutil      54. 20.100 / 54. 20.100
  libavcodec     56. 26.100 / 56. 26.100
  libavformat    56. 25.101 / 56. 25.101
  libavdevice    56.  4.100 / 56.  4.100
  libavfilter     5. 11.102 /  5. 11.102
  libavresample   2.  1.  0 /  2.  1.  0
  libswscale      3.  1.101 /  3.  1.101
  libswresample   1.  1.100 /  1.  1.100
  libpostproc    53.  3.100 / 53.  3.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'pipe:0':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    creation_time   : 2015-09-27 09:46:32
  Duration: 00:00:16.96, start: 0.000000, bitrate: N/A
    Stream #0:0(eng): Video: h264 (Baseline) (avc1 / 0x31637661), yuv420p, 640x480, 5744 kb/s, SAR 1:1 DAR 4:3, 28.68 fps, 28.67 tbr, 90k tbn, 180k tbc (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : VideoHandle
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, mono, fltp, 95 kb/s (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : SoundHandle
[libx264 @ 0xbe5000] using SAR=1/1
[libx264 @ 0xbe5000] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
[libx264 @ 0xbe5000] profile High, level 3.0
[libx264 @ 0xbe5000] 264 - core 146 - H.264/MPEG-4 AVC codec - Copyleft 2003-2015 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=6 lookahead_threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'camera_landscape_test.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    encoder         : Lavf56.25.101
    Stream #0:0(eng): Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 640x480 [SAR 1:1 DAR 4:3], q=-1--1, 28.67 fps, 11008 tbn, 28.67 tbc (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : VideoHandle
      encoder         : Lavc56.26.100 libx264
    Stream #0:1(eng): Audio: aac (libfaac) ([64][0][0][0] / 0x0040), 48000 Hz, mono, s16, 128 kb/s (default)
    Metadata:
      creation_time   : 2015-09-27 09:46:32
      handler_name    : SoundHandle
      encoder         : Lavc56.26.100 libfaac
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  Stream #0:1 -> #0:1 (aac (native) -> aac (libfaac))
frame=  201 fps= 70 q=-1.0 Lsize=     543kB time=00:00:07.01 bitrate= 634.0kbits/s dup=1 drop=0    
video:465kB audio:71kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.238381%
[libx264 @ 0xbe5000] frame I:1     Avg QP:21.12  size:  5005
[libx264 @ 0xbe5000] frame P:200   Avg QP:22.80  size:  2354
[libx264 @ 0xbe5000] mb I  I16..4: 17.2% 82.0%  0.8%
[libx264 @ 0xbe5000] mb P  I16..4:  5.2%  9.7%  0.0%  P16..4: 53.7%  3.0%  3.4%  0.0%  0.0%    skip:25.0%
[libx264 @ 0xbe5000] 8x8 transform intra:65.7% inter:97.4%
[libx264 @ 0xbe5000] coded y,uvDC,uvAC intra: 27.7% 59.6% 0.0% inter: 20.1% 49.5% 0.0%
[libx264 @ 0xbe5000] i16 v,h,dc,p: 21% 31% 24% 24%
[libx264 @ 0xbe5000] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 12% 14% 58%  3%  3%  3%  3%  2%  2%
[libx264 @ 0xbe5000] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 14%  6% 66%  4%  3%  3%  3%  1%  1%
[libx264 @ 0xbe5000] i8c dc,h,v,p: 62% 21% 16%  1%
[libx264 @ 0xbe5000] Weighted P-Frames: Y:0.0% UV:0.0%
[libx264 @ 0xbe5000] ref P L0: 38.2%  4.0% 33.1% 24.8%
[libx264 @ 0xbe5000] kb/s:542.91

Todo funciona bien si se hace referencia a la entrada como un archivo ( idirectamente), pero la tubería es obligatoria. Como prueba, también se probó un archivo de Youtube, resultando exitoso. La pregunta aquí es por qué falla esta operación para este video en particular y cómo solucionarlo.

Editar: enlace de vídeo temporal -http://tempsend.com/8F6F119BCA

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