ffprobe The.Last.Boy.Scout.1991.1080p.mkv -count_frames -show_entries stream=nb_read_frames
ffprobe version 2.5.4 Copyright (c) 2007-2015 the FFmpeg developers
  built on Feb 13 2015 17:05:44 with gcc 4.9.2 (GCC) 20150204 (prerelease)
  configuration: --prefix=/usr --disable-debug --disable-static --disable-stripping --enable-avisynth --enable-avresample --enable-fontconfig --enable-gnutls --enable-gpl --enable-libass --enable-libbluray --enable-libfreetype --enable-libfribidi --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libspeex --enable-libtheora --enable-libv4l2 --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libxvid --enable-runtime-cpudetect --enable-shared --enable-swresample --enable-vdpau --enable-version3 --enable-x11grab
  libavutil      54. 15.100 / 54. 15.100
  libavcodec     56. 13.100 / 56. 13.100
  libavformat    56. 15.102 / 56. 15.102
  libavdevice    56.  3.100 / 56.  3.100
  libavfilter     5.  2.103 /  5.  2.103
  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, matroska,webm, from 'The.Last.Boy.Scout.1991.1080p.mkv':
  Metadata:
    encoder         : libebml v1.2.3 + libmatroska v1.3.0
    creation_time   : 2013-03-16 12:35:32
  Duration: 01:45:25.95, start: 0.000000, bitrate: 11348 kb/s
    Stream #0:0(eng): Video: h264 (Main), yuv420p(tv, bt709), 1920x800, SAR 1:1 DAR 12:5, 23.98 fps, 23.98 tbr, 1k tbn, 180k tbc (default)
    Stream #0:1(eng): Audio: dts (DTS), 48000 Hz, 5.1(side), fltp, 1536 kb/s (default)
[STREAM]
nb_read_frames=151648
[/STREAM]
[STREAM]
nb_read_frames=593058
[/STREAM]