[FFmpeg-user] How to get he total number of frames

[Peter White]

On Tue, Mar 09, 2021 at 01:07:41PM +0100, Nicolas George wrote:
> Peter White (12021-03-09):
> > ffmpeg -i input.mkv -an -sn -c copy -f null -
> 
> -c copy tells ffmpeg to dispense with the decoder, which means it does
> not count frames but packets. Have you tried telling ffprobe to count
> packets?

I have now, but it returns 'N/A'. Now that I see that, I might have
tried it way back when, even, and have forgotten about it.

ffprobe -count_packets -select_streams v:0 -show_entries stream=nb_read_frames -of default=nokey=1:noprint_wrappers=1 input.mkv
ffprobe version n4.3.1-221-gd08bcbffff Copyright (c) 2007-2021 the FFmpeg developers
  built with AMD clang version 11.0.0 (CLANG: AOCC_2.3.0-Build#85 2020_11_10) (based on LLVM Mirror.Version.11.0.0)
  configuration: --cc='ccache clang' --cxx='ccache clang++' --objcc='ccache clang' --dep-cc='ccache clang' --extra-cflags='-march=native' --extra-cxxflags='-march=native' --extra-objcflags='-march=native' --enable-hardcoded-tables --enable-shared --enable-gpl --enable-version3 --enable-nonfree --disable-runtime-cpudetect --enable-libx264 --enable-libx265 --enable-libvorbis --enable-gnutls --enable-opengl --enable-libopus --enable-libfreetype --enable-libfontconfig --enable-libfribidi --enable-libsoxr --enable-libzvbi --enable-libmp3lame --enable-ladspa --enable-lv2 --enable-libbs2b --enable-libdrm --enable-libvpx --enable-libbluray
  libavutil      56. 51.100 / 56. 51.100
  libavcodec     58. 91.100 / 58. 91.100
  libavformat    58. 45.100 / 58. 45.100
  libavdevice    58. 10.100 / 58. 10.100
  libavfilter     7. 85.100 /  7. 85.100
  libswscale      5.  7.100 /  5.  7.100
  libswresample   3.  7.100 /  3.  7.100
  libpostproc    55.  7.100 / 55.  7.100
Input #0, matroska,webm, from 'input.mkv':
  Metadata:
    creation_time   : 2021-02-16T19:59:37.000000Z
    ENCODER         : Lavf58.45.100
  Duration: 00:21:40.91, start: -0.007000, bitrate: 1319 kb/s
    Chapter #0:0: start 0.000000, end 432.557000
    Metadata:
      title           : 00:00:00.000
    Chapter #0:1: start 432.557000, end 866.824000
    Metadata:
      title           : 00:07:12.557
    Chapter #0:2: start 866.824000, end 1267.475000
    Metadata:
      title           : 00:14:26.824
    Chapter #0:3: start 1267.475000, end 1300.906000
    Metadata:
      title           : 00:21:07.475
    Stream #0:0: Video: hevc (Main 10), yuv420p10le(tv, bt709), 768x432 [SAR 1:1 DAR 16:9], 23.98 fps, 23.98 tbr, 1k tbn, 23.98 tbc (default)
    Metadata:
      BPS-eng         : 1021384
      DURATION-eng    : 00:21:40.716000000
      NUMBER_OF_FRAMES-eng: 31186
      NUMBER_OF_BYTES-eng: 166066371
      _STATISTICS_WRITING_APP-eng: mkvmerge v45.0.0 ('Heaven in Pennies') 64-bit
      _STATISTICS_WRITING_DATE_UTC-eng: 2021-02-16 19:59:37
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
    Stream #0:1(eng): Audio: opus, 48000 Hz, 5.1, fltp (default)
    Metadata:
      title           : English
      ENCODER         : Lavc58.91.100 libopus
      BPS-eng         : 230805
      DURATION-eng    : 00:21:40.760000000
      NUMBER_OF_FRAMES-eng: 65039
      NUMBER_OF_BYTES-eng: 37527832
      _STATISTICS_WRITING_APP-eng: mkvmerge v45.0.0 ('Heaven in Pennies') 64-bit
      _STATISTICS_WRITING_DATE_UTC-eng: 2021-02-16 19:59:37
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
    Stream #0:2(eng): Audio: aac (HE-AAC), 48000 Hz, stereo, fltp
    Metadata:
      title           : English
      BPS-eng         : 63925
      DURATION-eng    : 00:21:40.906000000
      NUMBER_OF_FRAMES-eng: 30490
      NUMBER_OF_BYTES-eng: 10395117
      _STATISTICS_WRITING_APP-eng: mkvmerge v45.0.0 ('Heaven in Pennies') 64-bit
      _STATISTICS_WRITING_DATE_UTC-eng: 2021-02-16 19:59:37
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
    Stream #0:3(eng): Subtitle: subrip
    Metadata:
      title           : English
      BPS-eng         : 72
      DURATION-eng    : 00:21:36.169000000
      NUMBER_OF_FRAMES-eng: 370
      NUMBER_OF_BYTES-eng: 11676
      _STATISTICS_WRITING_APP-eng: mkvmerge v45.0.0 ('Heaven in Pennies') 64-bit
      _STATISTICS_WRITING_DATE_UTC-eng: 2021-02-16 19:59:37
      _STATISTICS_TAGS-eng: BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES
N/A


Peter