ffmpeg -v 1 -fflags +genpts -analyzeduration 1000000k -probesize 1000000k -i input.iso -y -c copy output.mkv

fmpeg version 3.4 Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 4.9.4 (GCC)
  configuration: --prefix=/pkg --enable-static --disable-shared --enable-gpl --enable-version3 --enable-nonfree --enable-runtime-cpudetect --disable-ffplay --disable-ffserver --disable-network --disable-libxcb --disable-xlib --disable-sndio --enable-avresample --enable-libopus --enable-libmp3lame --enable-libwavpack --enable-libgsm --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libspeex --enable-libvpx
  libavutil      55. 78.100 / 55. 78.100
  libavcodec     57.107.100 / 57.107.100
  libavformat    57. 83.100 / 57. 83.100
  libavdevice    57. 10.100 / 57. 10.100
  libavfilter     6.107.100 /  6.107.100
  libavresample   3.  7.  0 /  3.  7.  0
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Input #0, mpeg, from 'input.iso':
  Duration: 00:28:24.76, start: 0.287267, bitrate: 35438 kb/s
    Stream #0:0[0x1bf]: Data: dvd_nav_packet
    Stream #0:1[0x1e0]: Video: mpeg2video (Main), 1 reference frame, yuv420p(tv, progressive, left), 720x576 [SAR 64:45 DAR 16:9], 8000 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc
    Stream #0:2[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
    Stream #0:3[0x20]: Subtitle: dvd_subtitle
    Stream #0:4[0x21]: Subtitle: dvd_subtitle
Output #0, matroska, to 'output.mkv':
  Metadata:
    encoder         : Lavf57.83.100
    Stream #0:0: Video: mpeg2video (Main), 1 reference frame (mpg2 / 0x3267706D), yuv420p(tv, progressive, left), 720x576 (0x0) [SAR 64:45 DAR 16:9], q=2-31, 8000 kb/s, 25 fps, 25 tbr, 1k tbn, 90k tbc
    Stream #0:1: Audio: ac3 ([0] [0][0] / 0x2000), 48000 Hz, 5.1(side), fltp, 448 kb/s
Stream mapping:
  Stream #0:1 -> #0:0 (copy)
  Stream #0:2 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame=13156 fps=4684 q=-1.0 Lsize=  540291kB time=00:08:46.12 bitrate=8412.6kbits/s speed= 187x
video:511413kB audio:28612kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.049241%
Input file #0 (input.iso):
  Input stream #0:0 (data): 0 packets read (0 bytes);
  Input stream #0:1 (video): 13156 packets read (523687178 bytes);
  Input stream #0:2 (audio): 16439 packets read (29298176 bytes);
  Input stream #0:3 (subtitle): 0 packets read (0 bytes);
  Input stream #0:4 (subtitle): 0 packets read (0 bytes);
  Total: 29595 packets (552985354 bytes) demuxed
Output file #0 (output.mkv):
  Output stream #0:0 (video): 13156 packets muxed (523687178 bytes);
  Output stream #0:1 (audio): 16439 packets muxed (29298176 bytes);
  Total: 29595 packets (552985354 bytes) muxed