tombbraindamage> ass not working

ffmpeg -i video.mkv -vf "ass=video.mkv" out.avi
ffmpeg version 2.5.10-0ubuntu0.15.04.1 Copyright (c) 2000-2016 the FFmpeg developers
  built with gcc 4.9.2 (Ubuntu 4.9.2-10ubuntu13)
  configuration: --prefix=/usr --extra-version=0ubuntu0.15.04.1 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --shlibdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --enable-shared --disable-stripping --enable-avresample --enable-avisynth --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-libschroedinger --enable-libshine --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libwavpack --enable-libwebp --enable-libxvid --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzvbi --enable-libzmq --enable-frei0r --enable-libvpx --enable-libx264 --enable-libsoxr --enable-gnutls --enable-openal --enable-libopencv --enable-librtmp --enable-libx265
  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
[aac @ 0x175cce0] This stream seems to incorrectly report its last channel as LFE[3], mapping to LFE[0]
[aac @ 0x170a900] This stream seems to incorrectly report its last channel as LFE[3], mapping to LFE[0]
Input #0, matroska,webm, from 'video.mkv':
  Metadata:
    encoder         : libebml v0.7.7 + libmatroska v0.8.1
    creation_time   : 2009-12-25 04:43:30
  Duration: 00:24:30.10, start: 0.000000, bitrate: 3861 kb/s
    Chapter #0:0: start 0.000000, end 90.412000
    Metadata:
      title           : Opening
    Chapter #0:1: start 90.412000, end 671.962000
    Metadata:
      title           : Part 1
    Chapter #0:2: start 671.962000, end 1380.046000
    Metadata:
      title           : Part 2
    Chapter #0:3: start 1380.046000, end 1470.101000
    Metadata:
      title           : Ending
    Stream #0:0: Video: h264 (High), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 24 fps, 24 tbr, 1k tbn, 59.94 tbc (default)
    Stream #0:1(eng): Audio: aac (LC), 48000 Hz, 5.1, fltp (default)
    Metadata:
      title           : English Dolby Digital 5.1ch AAC
    Stream #0:2(jpn): Audio: aac (LC), 48000 Hz, 5.1, fltp
    Metadata:
      title           : Japanese Dolby Digital 5.1ch AAC
    Stream #0:3(eng): Subtitle: ass (default)
    Metadata:
      title           : English Lyrics/Signs
    Stream #0:4(eng): Subtitle: ass
    Metadata:
      title           : English Subtitles
    Stream #0:5: Attachment: ttf
    Metadata:
      filename        : BellGothicStd-Black.otf
      mimetype        : application/x-truetype-font
    Stream #0:6: Attachment: ttf
    Metadata:
      filename        : BellGothicStd-Bold.otf
      mimetype        : application/x-truetype-font
    Stream #0:7: Attachment: ttf
    Metadata:
      filename        : Brianne_s_hand.ttf
      mimetype        : application/x-truetype-font
    Stream #0:8: Attachment: ttf
    Metadata:
      filename        : ITCKabelStd-Medium.otf
      mimetype        : application/x-truetype-font
    Stream #0:9: Attachment: ttf
    Metadata:
      filename        : kkberktp.ttf
      mimetype        : application/x-truetype-font
    Stream #0:10: Attachment: ttf
    Metadata:
      filename        : POORICH.TTF
      mimetype        : application/x-truetype-font
    Stream #0:11: Attachment: ttf
    Metadata:
      filename        : X-SCALE.TTF
      mimetype        : application/x-truetype-font
    Stream #0:12: Attachment: ttf
    Metadata:
      filename        : YOUTHAN_.ttf
      mimetype        : application/x-truetype-font
    Stream #0:13: Attachment: ttf
    Metadata:
      filename        : YOUTHANI.ttf
      mimetype        : application/x-truetype-font
    Stream #0:14: Attachment: ttf
    Metadata:
      filename        : YOUTTX__.ttf
      mimetype        : application/x-truetype-font
[Parsed_ass_0 @ 0x1709fc0] Could not create a libass track when reading file 'video.mkv'
[AVFilterGraph @ 0x177f740] Error initializing filter 'ass' with args 'video.mkv'
Error opening filters!
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