Is there a way to extract sub+idx subtitle file from VOB files other than using VSRip?

Question

I have some DVDs that fail to extract sub/idx subtitle file from VOB files by using VSRip.

Is there a way to extract sub/idx file by ffmpeg or by some another software?

There are six *.VOB files from VTS_01_0.VOB to VTS_01_5.VOB. These are result of ffprobe two of them.

$ ffprobe.exe "VTS_01_0.VOB"

    ffprobe version N-72709-g42db4aa Copyright (c) 2007-2015 the FFmpeg developers
      built with gcc 4.9.2 (GCC)
      configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmfx --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
      libavutil      54. 27.100 / 54. 27.100
      libavcodec     56. 41.100 / 56. 41.100
      libavformat    56. 34.100 / 56. 34.100
      libavdevice    56.  4.100 / 56.  4.100
      libavfilter     5. 16.101 /  5. 16.101
      libswscale      3.  1.101 /  3.  1.101
      libswresample   1.  2.100 /  1.  2.100
      libpostproc    53.  3.100 / 53.  3.100
    Input #0, mpeg, from 'VTS_01_0.VOB':
      Duration: 00:00:29.98, start: 0.280633, bitrate: 48825 kb/s
        Stream #0:0[0x1bf]: Data: dvd_nav_packet
        Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv), 720x480 [SAR 32:27 DAR 16:9], 7000 kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
        Stream #0:2[0x80]: Audio: ac3, 48000 Hz, stereo, fltp, 448 kb/s
    Unsupported codec with id 1145979222 for input stream 0

$ ffprobe.exe "VTS_01_1.VOB"

    ffprobe version N-72709-g42db4aa Copyright (c) 2007-2015 the FFmpeg developers
      built with gcc 4.9.2 (GCC)
      configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libdcadec --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmfx --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-aacenc --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-lzma --enable-decklink --enable-zlib
      libavutil      54. 27.100 / 54. 27.100
      libavcodec     56. 41.100 / 56. 41.100
      libavformat    56. 34.100 / 56. 34.100
      libavdevice    56.  4.100 / 56.  4.100
      libavfilter     5. 16.101 /  5. 16.101
      libswscale      3.  1.101 /  3.  1.101
      libswresample   1.  2.100 /  1.  2.100
      libpostproc    53.  3.100 / 53.  3.100
    Input #0, mpeg, from 'VTS_01_1.VOB':
      Duration: 00:34:29.50, start: 0.280633, bitrate: 4150 kb/s
        Stream #0:0[0x1bf]: Data: dvd_nav_packet
        Stream #0:1[0x1e0]: Video: mpeg2video (Main), yuv420p(tv, smpte170m), 720x480 [SAR 32:27 DAR 16:9], max. 8000 kb/s, 28.67 fps, 59.94 tbr, 90k tbn, 59.94 tbc
        Stream #0:2[0x80]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
        Stream #0:3[0x81]: Audio: ac3, 48000 Hz, 5.1(side), fltp, 448 kb/s
    Unsupported codec with id 1145979222 for input stream 0

Answer 1

There's a little app I've used called MakeMKV, which is still in beta. It's a bit annoying to use on a regular basis as the developers only give it a temporary key and you have to keep going back to the site once the key expires to obtain the current registration key.

However is does a very quick job of converting a DVD into an mkv file, from which you can extract whatever you require.

The website is www.makemkv.com

I use a Mac, and use imkvextract to get the streams I need. Usually works - can't handle bluray but has worked pretty well on regular DVDs.